[XFS] cleanup vnode useage in xfs_iget.c

[linux-2.6] / fs / xfs / xfs_bmap.c

/*
 * Copyright (c) 2000-2006 Silicon Graphics, Inc.
 * All Rights Reserved.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it would be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write the Free Software Foundation,
 * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */
#include "xfs.h"
#include "xfs_fs.h"
#include "xfs_types.h"
#include "xfs_bit.h"
#include "xfs_log.h"
#include "xfs_inum.h"
#include "xfs_trans.h"
#include "xfs_sb.h"
#include "xfs_ag.h"
#include "xfs_dir2.h"
#include "xfs_da_btree.h"
#include "xfs_bmap_btree.h"
#include "xfs_alloc_btree.h"
#include "xfs_ialloc_btree.h"
#include "xfs_dir2_sf.h"
#include "xfs_attr_sf.h"
#include "xfs_dinode.h"
#include "xfs_inode.h"
#include "xfs_btree.h"
#include "xfs_dmapi.h"
#include "xfs_mount.h"
#include "xfs_ialloc.h"
#include "xfs_itable.h"
#include "xfs_dir2_data.h"
#include "xfs_dir2_leaf.h"
#include "xfs_dir2_block.h"
#include "xfs_inode_item.h"
#include "xfs_extfree_item.h"
#include "xfs_alloc.h"
#include "xfs_bmap.h"
#include "xfs_rtalloc.h"
#include "xfs_error.h"
#include "xfs_attr_leaf.h"
#include "xfs_rw.h"
#include "xfs_quota.h"
#include "xfs_trans_space.h"
#include "xfs_buf_item.h"
#include "xfs_filestream.h"
#include "xfs_vnodeops.h"


#ifdef DEBUG
STATIC void
xfs_bmap_check_leaf_extents(xfs_btree_cur_t *cur, xfs_inode_t *ip, int whichfork);
#endif

kmem_zone_t             *xfs_bmap_free_item_zone;

/*
 * Prototypes for internal bmap routines.
 */


/*
 * Called from xfs_bmap_add_attrfork to handle extents format files.
 */
STATIC int                                      /* error */
xfs_bmap_add_attrfork_extents(
        xfs_trans_t             *tp,            /* transaction pointer */
        xfs_inode_t             *ip,            /* incore inode pointer */
        xfs_fsblock_t           *firstblock,    /* first block allocated */
        xfs_bmap_free_t         *flist,         /* blocks to free at commit */
        int                     *flags);        /* inode logging flags */

/*
 * Called from xfs_bmap_add_attrfork to handle local format files.
 */
STATIC int                                      /* error */
xfs_bmap_add_attrfork_local(
        xfs_trans_t             *tp,            /* transaction pointer */
        xfs_inode_t             *ip,            /* incore inode pointer */
        xfs_fsblock_t           *firstblock,    /* first block allocated */
        xfs_bmap_free_t         *flist,         /* blocks to free at commit */
        int                     *flags);        /* inode logging flags */

/*
 * Called by xfs_bmapi to update file extent records and the btree
 * after allocating space (or doing a delayed allocation).
 */
STATIC int                              /* error */
xfs_bmap_add_extent(
        xfs_inode_t             *ip,    /* incore inode pointer */
        xfs_extnum_t            idx,    /* extent number to update/insert */
        xfs_btree_cur_t         **curp, /* if *curp is null, not a btree */
        xfs_bmbt_irec_t         *new,   /* new data to add to file extents */
        xfs_fsblock_t           *first, /* pointer to firstblock variable */
        xfs_bmap_free_t         *flist, /* list of extents to be freed */
        int                     *logflagsp, /* inode logging flags */
        xfs_extdelta_t          *delta, /* Change made to incore extents */
        int                     whichfork, /* data or attr fork */
        int                     rsvd);  /* OK to allocate reserved blocks */

/*
 * Called by xfs_bmap_add_extent to handle cases converting a delayed
 * allocation to a real allocation.
 */
STATIC int                              /* error */
xfs_bmap_add_extent_delay_real(
        xfs_inode_t             *ip,    /* incore inode pointer */
        xfs_extnum_t            idx,    /* extent number to update/insert */
        xfs_btree_cur_t         **curp, /* if *curp is null, not a btree */
        xfs_bmbt_irec_t         *new,   /* new data to add to file extents */
        xfs_filblks_t           *dnew,  /* new delayed-alloc indirect blocks */
        xfs_fsblock_t           *first, /* pointer to firstblock variable */
        xfs_bmap_free_t         *flist, /* list of extents to be freed */
        int                     *logflagsp, /* inode logging flags */
        xfs_extdelta_t          *delta, /* Change made to incore extents */
        int                     rsvd);  /* OK to allocate reserved blocks */

/*
 * Called by xfs_bmap_add_extent to handle cases converting a hole
 * to a delayed allocation.
 */
STATIC int                              /* error */
xfs_bmap_add_extent_hole_delay(
        xfs_inode_t             *ip,    /* incore inode pointer */
        xfs_extnum_t            idx,    /* extent number to update/insert */
        xfs_bmbt_irec_t         *new,   /* new data to add to file extents */
        int                     *logflagsp,/* inode logging flags */
        xfs_extdelta_t          *delta, /* Change made to incore extents */
        int                     rsvd);  /* OK to allocate reserved blocks */

/*
 * Called by xfs_bmap_add_extent to handle cases converting a hole
 * to a real allocation.
 */
STATIC int                              /* error */
xfs_bmap_add_extent_hole_real(
        xfs_inode_t             *ip,    /* incore inode pointer */
        xfs_extnum_t            idx,    /* extent number to update/insert */
        xfs_btree_cur_t         *cur,   /* if null, not a btree */
        xfs_bmbt_irec_t         *new,   /* new data to add to file extents */
        int                     *logflagsp, /* inode logging flags */
        xfs_extdelta_t          *delta, /* Change made to incore extents */
        int                     whichfork); /* data or attr fork */

/*
 * Called by xfs_bmap_add_extent to handle cases converting an unwritten
 * allocation to a real allocation or vice versa.
 */
STATIC int                              /* error */
xfs_bmap_add_extent_unwritten_real(
        xfs_inode_t             *ip,    /* incore inode pointer */
        xfs_extnum_t            idx,    /* extent number to update/insert */
        xfs_btree_cur_t         **curp, /* if *curp is null, not a btree */
        xfs_bmbt_irec_t         *new,   /* new data to add to file extents */
        int                     *logflagsp, /* inode logging flags */
        xfs_extdelta_t          *delta); /* Change made to incore extents */

/*
 * xfs_bmap_alloc is called by xfs_bmapi to allocate an extent for a file.
 * It figures out where to ask the underlying allocator to put the new extent.
 */
STATIC int                              /* error */
xfs_bmap_alloc(
        xfs_bmalloca_t          *ap);   /* bmap alloc argument struct */

/*
 * Transform a btree format file with only one leaf node, where the
 * extents list will fit in the inode, into an extents format file.
 * Since the file extents are already in-core, all we have to do is
 * give up the space for the btree root and pitch the leaf block.
 */
STATIC int                              /* error */
xfs_bmap_btree_to_extents(
        xfs_trans_t             *tp,    /* transaction pointer */
        xfs_inode_t             *ip,    /* incore inode pointer */
        xfs_btree_cur_t         *cur,   /* btree cursor */
        int                     *logflagsp, /* inode logging flags */
        int                     whichfork); /* data or attr fork */

/*
 * Called by xfs_bmapi to update file extent records and the btree
 * after removing space (or undoing a delayed allocation).
 */
STATIC int                              /* error */
xfs_bmap_del_extent(
        xfs_inode_t             *ip,    /* incore inode pointer */
        xfs_trans_t             *tp,    /* current trans pointer */
        xfs_extnum_t            idx,    /* extent number to update/insert */
        xfs_bmap_free_t         *flist, /* list of extents to be freed */
        xfs_btree_cur_t         *cur,   /* if null, not a btree */
        xfs_bmbt_irec_t         *new,   /* new data to add to file extents */
        int                     *logflagsp,/* inode logging flags */
        xfs_extdelta_t          *delta, /* Change made to incore extents */
        int                     whichfork, /* data or attr fork */
        int                     rsvd);   /* OK to allocate reserved blocks */

/*
 * Remove the entry "free" from the free item list.  Prev points to the
 * previous entry, unless "free" is the head of the list.
 */
STATIC void
xfs_bmap_del_free(
        xfs_bmap_free_t         *flist, /* free item list header */
        xfs_bmap_free_item_t    *prev,  /* previous item on list, if any */
        xfs_bmap_free_item_t    *free); /* list item to be freed */

/*
 * Convert an extents-format file into a btree-format file.
 * The new file will have a root block (in the inode) and a single child block.
 */
STATIC int                                      /* error */
xfs_bmap_extents_to_btree(
        xfs_trans_t             *tp,            /* transaction pointer */
        xfs_inode_t             *ip,            /* incore inode pointer */
        xfs_fsblock_t           *firstblock,    /* first-block-allocated */
        xfs_bmap_free_t         *flist,         /* blocks freed in xaction */
        xfs_btree_cur_t         **curp,         /* cursor returned to caller */
        int                     wasdel,         /* converting a delayed alloc */
        int                     *logflagsp,     /* inode logging flags */
        int                     whichfork);     /* data or attr fork */

/*
 * Convert a local file to an extents file.
 * This code is sort of bogus, since the file data needs to get
 * logged so it won't be lost.  The bmap-level manipulations are ok, though.
 */
STATIC int                              /* error */
xfs_bmap_local_to_extents(
        xfs_trans_t     *tp,            /* transaction pointer */
        xfs_inode_t     *ip,            /* incore inode pointer */
        xfs_fsblock_t   *firstblock,    /* first block allocated in xaction */
        xfs_extlen_t    total,          /* total blocks needed by transaction */
        int             *logflagsp,     /* inode logging flags */
        int             whichfork);     /* data or attr fork */

/*
 * Search the extents list for the inode, for the extent containing bno.
 * If bno lies in a hole, point to the next entry.  If bno lies past eof,
 * *eofp will be set, and *prevp will contain the last entry (null if none).
 * Else, *lastxp will be set to the index of the found
 * entry; *gotp will contain the entry.
 */
STATIC xfs_bmbt_rec_host_t *            /* pointer to found extent entry */
xfs_bmap_search_extents(
        xfs_inode_t     *ip,            /* incore inode pointer */
        xfs_fileoff_t   bno,            /* block number searched for */
        int             whichfork,      /* data or attr fork */
        int             *eofp,          /* out: end of file found */
        xfs_extnum_t    *lastxp,        /* out: last extent index */
        xfs_bmbt_irec_t *gotp,          /* out: extent entry found */
        xfs_bmbt_irec_t *prevp);        /* out: previous extent entry found */

/*
 * Check the last inode extent to determine whether this allocation will result
 * in blocks being allocated at the end of the file. When we allocate new data
 * blocks at the end of the file which do not start at the previous data block,
 * we will try to align the new blocks at stripe unit boundaries.
 */
STATIC int                              /* error */
xfs_bmap_isaeof(
        xfs_inode_t     *ip,            /* incore inode pointer */
        xfs_fileoff_t   off,            /* file offset in fsblocks */
        int             whichfork,      /* data or attribute fork */
        char            *aeof);         /* return value */

#ifdef XFS_BMAP_TRACE
/*
 * Add bmap trace entry prior to a call to xfs_iext_remove.
 */
STATIC void
xfs_bmap_trace_delete(
        const char      *fname,         /* function name */
        char            *desc,          /* operation description */
        xfs_inode_t     *ip,            /* incore inode pointer */
        xfs_extnum_t    idx,            /* index of entry(entries) deleted */
        xfs_extnum_t    cnt,            /* count of entries deleted, 1 or 2 */
        int             whichfork);     /* data or attr fork */

/*
 * Add bmap trace entry prior to a call to xfs_iext_insert, or
 * reading in the extents list from the disk (in the btree).
 */
STATIC void
xfs_bmap_trace_insert(
        const char      *fname,         /* function name */
        char            *desc,          /* operation description */
        xfs_inode_t     *ip,            /* incore inode pointer */
        xfs_extnum_t    idx,            /* index of entry(entries) inserted */
        xfs_extnum_t    cnt,            /* count of entries inserted, 1 or 2 */
        xfs_bmbt_irec_t *r1,            /* inserted record 1 */
        xfs_bmbt_irec_t *r2,            /* inserted record 2 or null */
        int             whichfork);     /* data or attr fork */

/*
 * Add bmap trace entry after updating an extent record in place.
 */
STATIC void
xfs_bmap_trace_post_update(
        const char      *fname,         /* function name */
        char            *desc,          /* operation description */
        xfs_inode_t     *ip,            /* incore inode pointer */
        xfs_extnum_t    idx,            /* index of entry updated */
        int             whichfork);     /* data or attr fork */

/*
 * Add bmap trace entry prior to updating an extent record in place.
 */
STATIC void
xfs_bmap_trace_pre_update(
        const char      *fname,         /* function name */
        char            *desc,          /* operation description */
        xfs_inode_t     *ip,            /* incore inode pointer */
        xfs_extnum_t    idx,            /* index of entry to be updated */
        int             whichfork);     /* data or attr fork */

#define XFS_BMAP_TRACE_DELETE(d,ip,i,c,w)       \
        xfs_bmap_trace_delete(__FUNCTION__,d,ip,i,c,w)
#define XFS_BMAP_TRACE_INSERT(d,ip,i,c,r1,r2,w) \
        xfs_bmap_trace_insert(__FUNCTION__,d,ip,i,c,r1,r2,w)
#define XFS_BMAP_TRACE_POST_UPDATE(d,ip,i,w)    \
        xfs_bmap_trace_post_update(__FUNCTION__,d,ip,i,w)
#define XFS_BMAP_TRACE_PRE_UPDATE(d,ip,i,w)     \
        xfs_bmap_trace_pre_update(__FUNCTION__,d,ip,i,w)
#else
#define XFS_BMAP_TRACE_DELETE(d,ip,i,c,w)
#define XFS_BMAP_TRACE_INSERT(d,ip,i,c,r1,r2,w)
#define XFS_BMAP_TRACE_POST_UPDATE(d,ip,i,w)
#define XFS_BMAP_TRACE_PRE_UPDATE(d,ip,i,w)
#endif  /* XFS_BMAP_TRACE */

/*
 * Compute the worst-case number of indirect blocks that will be used
 * for ip's delayed extent of length "len".
 */
STATIC xfs_filblks_t
xfs_bmap_worst_indlen(
        xfs_inode_t             *ip,    /* incore inode pointer */
        xfs_filblks_t           len);   /* delayed extent length */

#ifdef DEBUG
/*
 * Perform various validation checks on the values being returned
 * from xfs_bmapi().
 */
STATIC void
xfs_bmap_validate_ret(
        xfs_fileoff_t           bno,
        xfs_filblks_t           len,
        int                     flags,
        xfs_bmbt_irec_t         *mval,
        int                     nmap,
        int                     ret_nmap);
#else
#define xfs_bmap_validate_ret(bno,len,flags,mval,onmap,nmap)
#endif /* DEBUG */

#if defined(XFS_RW_TRACE)
STATIC void
xfs_bunmap_trace(
        xfs_inode_t             *ip,
        xfs_fileoff_t           bno,
        xfs_filblks_t           len,
        int                     flags,
        inst_t                  *ra);
#else
#define xfs_bunmap_trace(ip, bno, len, flags, ra)
#endif  /* XFS_RW_TRACE */

STATIC int
xfs_bmap_count_tree(
        xfs_mount_t     *mp,
        xfs_trans_t     *tp,
        xfs_ifork_t     *ifp,
        xfs_fsblock_t   blockno,
        int             levelin,
        int             *count);

STATIC int
xfs_bmap_count_leaves(
        xfs_ifork_t             *ifp,
        xfs_extnum_t            idx,
        int                     numrecs,
        int                     *count);

STATIC int
xfs_bmap_disk_count_leaves(
        xfs_extnum_t            idx,
        xfs_bmbt_block_t        *block,
        int                     numrecs,
        int                     *count);

/*
 * Bmap internal routines.
 */

/*
 * Called from xfs_bmap_add_attrfork to handle btree format files.
 */
STATIC int                                      /* error */
xfs_bmap_add_attrfork_btree(
        xfs_trans_t             *tp,            /* transaction pointer */
        xfs_inode_t             *ip,            /* incore inode pointer */
        xfs_fsblock_t           *firstblock,    /* first block allocated */
        xfs_bmap_free_t         *flist,         /* blocks to free at commit */
        int                     *flags)         /* inode logging flags */
{
        xfs_btree_cur_t         *cur;           /* btree cursor */
        int                     error;          /* error return value */
        xfs_mount_t             *mp;            /* file system mount struct */
        int                     stat;           /* newroot status */

        mp = ip->i_mount;
        if (ip->i_df.if_broot_bytes <= XFS_IFORK_DSIZE(ip))
                *flags |= XFS_ILOG_DBROOT;
        else {
                cur = xfs_btree_init_cursor(mp, tp, NULL, 0, XFS_BTNUM_BMAP, ip,
                        XFS_DATA_FORK);
                cur->bc_private.b.flist = flist;
                cur->bc_private.b.firstblock = *firstblock;
                if ((error = xfs_bmbt_lookup_ge(cur, 0, 0, 0, &stat)))
                        goto error0;
                ASSERT(stat == 1);      /* must be at least one entry */
                if ((error = xfs_bmbt_newroot(cur, flags, &stat)))
                        goto error0;
                if (stat == 0) {
                        xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
                        return XFS_ERROR(ENOSPC);
                }
                *firstblock = cur->bc_private.b.firstblock;
                cur->bc_private.b.allocated = 0;
                xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
        }
        return 0;
error0:
        xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
        return error;
}

/*
 * Called from xfs_bmap_add_attrfork to handle extents format files.
 */
STATIC int                                      /* error */
xfs_bmap_add_attrfork_extents(
        xfs_trans_t             *tp,            /* transaction pointer */
        xfs_inode_t             *ip,            /* incore inode pointer */
        xfs_fsblock_t           *firstblock,    /* first block allocated */
        xfs_bmap_free_t         *flist,         /* blocks to free at commit */
        int                     *flags)         /* inode logging flags */
{
        xfs_btree_cur_t         *cur;           /* bmap btree cursor */
        int                     error;          /* error return value */

        if (ip->i_d.di_nextents * sizeof(xfs_bmbt_rec_t) <= XFS_IFORK_DSIZE(ip))
                return 0;
        cur = NULL;
        error = xfs_bmap_extents_to_btree(tp, ip, firstblock, flist, &cur, 0,
                flags, XFS_DATA_FORK);
        if (cur) {
                cur->bc_private.b.allocated = 0;
                xfs_btree_del_cursor(cur,
                        error ? XFS_BTREE_ERROR : XFS_BTREE_NOERROR);
        }
        return error;
}

/*
 * Called from xfs_bmap_add_attrfork to handle local format files.
 */
STATIC int                                      /* error */
xfs_bmap_add_attrfork_local(
        xfs_trans_t             *tp,            /* transaction pointer */
        xfs_inode_t             *ip,            /* incore inode pointer */
        xfs_fsblock_t           *firstblock,    /* first block allocated */
        xfs_bmap_free_t         *flist,         /* blocks to free at commit */
        int                     *flags)         /* inode logging flags */
{
        xfs_da_args_t           dargs;          /* args for dir/attr code */
        int                     error;          /* error return value */
        xfs_mount_t             *mp;            /* mount structure pointer */

        if (ip->i_df.if_bytes <= XFS_IFORK_DSIZE(ip))
                return 0;
        if ((ip->i_d.di_mode & S_IFMT) == S_IFDIR) {
                mp = ip->i_mount;
                memset(&dargs, 0, sizeof(dargs));
                dargs.dp = ip;
                dargs.firstblock = firstblock;
                dargs.flist = flist;
                dargs.total = mp->m_dirblkfsbs;
                dargs.whichfork = XFS_DATA_FORK;
                dargs.trans = tp;
                error = xfs_dir2_sf_to_block(&dargs);
        } else
                error = xfs_bmap_local_to_extents(tp, ip, firstblock, 1, flags,
                        XFS_DATA_FORK);
        return error;
}

/*
 * Called by xfs_bmapi to update file extent records and the btree
 * after allocating space (or doing a delayed allocation).
 */
STATIC int                              /* error */
xfs_bmap_add_extent(
        xfs_inode_t             *ip,    /* incore inode pointer */
        xfs_extnum_t            idx,    /* extent number to update/insert */
        xfs_btree_cur_t         **curp, /* if *curp is null, not a btree */
        xfs_bmbt_irec_t         *new,   /* new data to add to file extents */
        xfs_fsblock_t           *first, /* pointer to firstblock variable */
        xfs_bmap_free_t         *flist, /* list of extents to be freed */
        int                     *logflagsp, /* inode logging flags */
        xfs_extdelta_t          *delta, /* Change made to incore extents */
        int                     whichfork, /* data or attr fork */
        int                     rsvd)   /* OK to use reserved data blocks */
{
        xfs_btree_cur_t         *cur;   /* btree cursor or null */
        xfs_filblks_t           da_new; /* new count del alloc blocks used */
        xfs_filblks_t           da_old; /* old count del alloc blocks used */
        int                     error;  /* error return value */
        xfs_ifork_t             *ifp;   /* inode fork ptr */
        int                     logflags; /* returned value */
        xfs_extnum_t            nextents; /* number of extents in file now */

        XFS_STATS_INC(xs_add_exlist);
        cur = *curp;
        ifp = XFS_IFORK_PTR(ip, whichfork);
        nextents = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t);
        ASSERT(idx <= nextents);
        da_old = da_new = 0;
        error = 0;
        /*
         * This is the first extent added to a new/empty file.
         * Special case this one, so other routines get to assume there are
         * already extents in the list.
         */
        if (nextents == 0) {
                XFS_BMAP_TRACE_INSERT("insert empty", ip, 0, 1, new, NULL,
                        whichfork);
                xfs_iext_insert(ifp, 0, 1, new);
                ASSERT(cur == NULL);
                ifp->if_lastex = 0;
                if (!ISNULLSTARTBLOCK(new->br_startblock)) {
                        XFS_IFORK_NEXT_SET(ip, whichfork, 1);
                        logflags = XFS_ILOG_CORE | XFS_ILOG_FEXT(whichfork);
                } else
                        logflags = 0;
                /* DELTA: single new extent */
                if (delta) {
                        if (delta->xed_startoff > new->br_startoff)
                                delta->xed_startoff = new->br_startoff;
                        if (delta->xed_blockcount <
                                        new->br_startoff + new->br_blockcount)
                                delta->xed_blockcount = new->br_startoff +
                                                new->br_blockcount;
                }
        }
        /*
         * Any kind of new delayed allocation goes here.
         */
        else if (ISNULLSTARTBLOCK(new->br_startblock)) {
                if (cur)
                        ASSERT((cur->bc_private.b.flags &
                                XFS_BTCUR_BPRV_WASDEL) == 0);
                if ((error = xfs_bmap_add_extent_hole_delay(ip, idx, new,
                                &logflags, delta, rsvd)))
                        goto done;
        }
        /*
         * Real allocation off the end of the file.
         */
        else if (idx == nextents) {
                if (cur)
                        ASSERT((cur->bc_private.b.flags &
                                XFS_BTCUR_BPRV_WASDEL) == 0);
                if ((error = xfs_bmap_add_extent_hole_real(ip, idx, cur, new,
                                &logflags, delta, whichfork)))
                        goto done;
        } else {
                xfs_bmbt_irec_t prev;   /* old extent at offset idx */

                /*
                 * Get the record referred to by idx.
                 */
                xfs_bmbt_get_all(xfs_iext_get_ext(ifp, idx), &prev);
                /*
                 * If it's a real allocation record, and the new allocation ends
                 * after the start of the referred to record, then we're filling
                 * in a delayed or unwritten allocation with a real one, or
                 * converting real back to unwritten.
                 */
                if (!ISNULLSTARTBLOCK(new->br_startblock) &&
                    new->br_startoff + new->br_blockcount > prev.br_startoff) {
                        if (prev.br_state != XFS_EXT_UNWRITTEN &&
                            ISNULLSTARTBLOCK(prev.br_startblock)) {
                                da_old = STARTBLOCKVAL(prev.br_startblock);
                                if (cur)
                                        ASSERT(cur->bc_private.b.flags &
                                                XFS_BTCUR_BPRV_WASDEL);
                                if ((error = xfs_bmap_add_extent_delay_real(ip,
                                        idx, &cur, new, &da_new, first, flist,
                                        &logflags, delta, rsvd)))
                                        goto done;
                        } else if (new->br_state == XFS_EXT_NORM) {
                                ASSERT(new->br_state == XFS_EXT_NORM);
                                if ((error = xfs_bmap_add_extent_unwritten_real(
                                        ip, idx, &cur, new, &logflags, delta)))
                                        goto done;
                        } else {
                                ASSERT(new->br_state == XFS_EXT_UNWRITTEN);
                                if ((error = xfs_bmap_add_extent_unwritten_real(
                                        ip, idx, &cur, new, &logflags, delta)))
                                        goto done;
                        }
                        ASSERT(*curp == cur || *curp == NULL);
                }
                /*
                 * Otherwise we're filling in a hole with an allocation.
                 */
                else {
                        if (cur)
                                ASSERT((cur->bc_private.b.flags &
                                        XFS_BTCUR_BPRV_WASDEL) == 0);
                        if ((error = xfs_bmap_add_extent_hole_real(ip, idx, cur,
                                        new, &logflags, delta, whichfork)))
                                goto done;
                }
        }

        ASSERT(*curp == cur || *curp == NULL);
        /*
         * Convert to a btree if necessary.
         */
        if (XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_EXTENTS &&
            XFS_IFORK_NEXTENTS(ip, whichfork) > ifp->if_ext_max) {
                int     tmp_logflags;   /* partial log flag return val */

                ASSERT(cur == NULL);
                error = xfs_bmap_extents_to_btree(ip->i_transp, ip, first,
                        flist, &cur, da_old > 0, &tmp_logflags, whichfork);
                logflags |= tmp_logflags;
                if (error)
                        goto done;
        }
        /*
         * Adjust for changes in reserved delayed indirect blocks.
         * Nothing to do for disk quotas here.
         */
        if (da_old || da_new) {
                xfs_filblks_t   nblks;

                nblks = da_new;
                if (cur)
                        nblks += cur->bc_private.b.allocated;
                ASSERT(nblks <= da_old);
                if (nblks < da_old)
                        xfs_mod_incore_sb(ip->i_mount, XFS_SBS_FDBLOCKS,
                                (int64_t)(da_old - nblks), rsvd);
        }
        /*
         * Clear out the allocated field, done with it now in any case.
         */
        if (cur) {
                cur->bc_private.b.allocated = 0;
                *curp = cur;
        }
done:
#ifdef DEBUG
        if (!error)
                xfs_bmap_check_leaf_extents(*curp, ip, whichfork);
#endif
        *logflagsp = logflags;
        return error;
}

/*
 * Called by xfs_bmap_add_extent to handle cases converting a delayed
 * allocation to a real allocation.
 */
STATIC int                              /* error */
xfs_bmap_add_extent_delay_real(
        xfs_inode_t             *ip,    /* incore inode pointer */
        xfs_extnum_t            idx,    /* extent number to update/insert */
        xfs_btree_cur_t         **curp, /* if *curp is null, not a btree */
        xfs_bmbt_irec_t         *new,   /* new data to add to file extents */
        xfs_filblks_t           *dnew,  /* new delayed-alloc indirect blocks */
        xfs_fsblock_t           *first, /* pointer to firstblock variable */
        xfs_bmap_free_t         *flist, /* list of extents to be freed */
        int                     *logflagsp, /* inode logging flags */
        xfs_extdelta_t          *delta, /* Change made to incore extents */
        int                     rsvd)   /* OK to use reserved data block allocation */
{
        xfs_btree_cur_t         *cur;   /* btree cursor */
        int                     diff;   /* temp value */
        xfs_bmbt_rec_host_t     *ep;    /* extent entry for idx */
        int                     error;  /* error return value */
        int                     i;      /* temp state */
        xfs_ifork_t             *ifp;   /* inode fork pointer */
        xfs_fileoff_t           new_endoff;     /* end offset of new entry */
        xfs_bmbt_irec_t         r[3];   /* neighbor extent entries */
                                        /* left is 0, right is 1, prev is 2 */
        int                     rval=0; /* return value (logging flags) */
        int                     state = 0;/* state bits, accessed thru macros */
        xfs_filblks_t           temp=0; /* value for dnew calculations */
        xfs_filblks_t           temp2=0;/* value for dnew calculations */
        int                     tmp_rval;       /* partial logging flags */
        enum {                          /* bit number definitions for state */
                LEFT_CONTIG,    RIGHT_CONTIG,
                LEFT_FILLING,   RIGHT_FILLING,
                LEFT_DELAY,     RIGHT_DELAY,
                LEFT_VALID,     RIGHT_VALID
        };

#define LEFT            r[0]
#define RIGHT           r[1]
#define PREV            r[2]
#define MASK(b)         (1 << (b))
#define MASK2(a,b)      (MASK(a) | MASK(b))
#define MASK3(a,b,c)    (MASK2(a,b) | MASK(c))
#define MASK4(a,b,c,d)  (MASK3(a,b,c) | MASK(d))
#define STATE_SET(b,v)  ((v) ? (state |= MASK(b)) : (state &= ~MASK(b)))
#define STATE_TEST(b)   (state & MASK(b))
#define STATE_SET_TEST(b,v)     ((v) ? ((state |= MASK(b)), 1) : \
                                       ((state &= ~MASK(b)), 0))
#define SWITCH_STATE            \
        (state & MASK4(LEFT_FILLING, RIGHT_FILLING, LEFT_CONTIG, RIGHT_CONTIG))

        /*
         * Set up a bunch of variables to make the tests simpler.
         */
        cur = *curp;
        ifp = XFS_IFORK_PTR(ip, XFS_DATA_FORK);
        ep = xfs_iext_get_ext(ifp, idx);
        xfs_bmbt_get_all(ep, &PREV);
        new_endoff = new->br_startoff + new->br_blockcount;
        ASSERT(PREV.br_startoff <= new->br_startoff);
        ASSERT(PREV.br_startoff + PREV.br_blockcount >= new_endoff);
        /*
         * Set flags determining what part of the previous delayed allocation
         * extent is being replaced by a real allocation.
         */
        STATE_SET(LEFT_FILLING, PREV.br_startoff == new->br_startoff);
        STATE_SET(RIGHT_FILLING,
                PREV.br_startoff + PREV.br_blockcount == new_endoff);
        /*
         * Check and set flags if this segment has a left neighbor.
         * Don't set contiguous if the combined extent would be too large.
         */
        if (STATE_SET_TEST(LEFT_VALID, idx > 0)) {
                xfs_bmbt_get_all(xfs_iext_get_ext(ifp, idx - 1), &LEFT);
                STATE_SET(LEFT_DELAY, ISNULLSTARTBLOCK(LEFT.br_startblock));
        }
        STATE_SET(LEFT_CONTIG,
                STATE_TEST(LEFT_VALID) && !STATE_TEST(LEFT_DELAY) &&
                LEFT.br_startoff + LEFT.br_blockcount == new->br_startoff &&
                LEFT.br_startblock + LEFT.br_blockcount == new->br_startblock &&
                LEFT.br_state == new->br_state &&
                LEFT.br_blockcount + new->br_blockcount <= MAXEXTLEN);
        /*
         * Check and set flags if this segment has a right neighbor.
         * Don't set contiguous if the combined extent would be too large.
         * Also check for all-three-contiguous being too large.
         */
        if (STATE_SET_TEST(RIGHT_VALID,
                        idx <
                        ip->i_df.if_bytes / (uint)sizeof(xfs_bmbt_rec_t) - 1)) {
                xfs_bmbt_get_all(xfs_iext_get_ext(ifp, idx + 1), &RIGHT);
                STATE_SET(RIGHT_DELAY, ISNULLSTARTBLOCK(RIGHT.br_startblock));
        }
        STATE_SET(RIGHT_CONTIG,
                STATE_TEST(RIGHT_VALID) && !STATE_TEST(RIGHT_DELAY) &&
                new_endoff == RIGHT.br_startoff &&
                new->br_startblock + new->br_blockcount ==
                    RIGHT.br_startblock &&
                new->br_state == RIGHT.br_state &&
                new->br_blockcount + RIGHT.br_blockcount <= MAXEXTLEN &&
                ((state & MASK3(LEFT_CONTIG, LEFT_FILLING, RIGHT_FILLING)) !=
                  MASK3(LEFT_CONTIG, LEFT_FILLING, RIGHT_FILLING) ||
                 LEFT.br_blockcount + new->br_blockcount + RIGHT.br_blockcount
                     <= MAXEXTLEN));
        error = 0;
        /*
         * Switch out based on the FILLING and CONTIG state bits.
         */
        switch (SWITCH_STATE) {

        case MASK4(LEFT_FILLING, RIGHT_FILLING, LEFT_CONTIG, RIGHT_CONTIG):
                /*
                 * Filling in all of a previously delayed allocation extent.
                 * The left and right neighbors are both contiguous with new.
                 */
                XFS_BMAP_TRACE_PRE_UPDATE("LF|RF|LC|RC", ip, idx - 1,
                        XFS_DATA_FORK);
                xfs_bmbt_set_blockcount(xfs_iext_get_ext(ifp, idx - 1),
                        LEFT.br_blockcount + PREV.br_blockcount +
                        RIGHT.br_blockcount);
                XFS_BMAP_TRACE_POST_UPDATE("LF|RF|LC|RC", ip, idx - 1,
                        XFS_DATA_FORK);
                XFS_BMAP_TRACE_DELETE("LF|RF|LC|RC", ip, idx, 2, XFS_DATA_FORK);
                xfs_iext_remove(ifp, idx, 2);
                ip->i_df.if_lastex = idx - 1;
                ip->i_d.di_nextents--;
                if (cur == NULL)
                        rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
                else {
                        rval = XFS_ILOG_CORE;
                        if ((error = xfs_bmbt_lookup_eq(cur, RIGHT.br_startoff,
                                        RIGHT.br_startblock,
                                        RIGHT.br_blockcount, &i)))
                                goto done;
                        ASSERT(i == 1);
                        if ((error = xfs_bmbt_delete(cur, &i)))
                                goto done;
                        ASSERT(i == 1);
                        if ((error = xfs_bmbt_decrement(cur, 0, &i)))
                                goto done;
                        ASSERT(i == 1);
                        if ((error = xfs_bmbt_update(cur, LEFT.br_startoff,
                                        LEFT.br_startblock,
                                        LEFT.br_blockcount +
                                        PREV.br_blockcount +
                                        RIGHT.br_blockcount, LEFT.br_state)))
                                goto done;
                }
                *dnew = 0;
                /* DELTA: Three in-core extents are replaced by one. */
                temp = LEFT.br_startoff;
                temp2 = LEFT.br_blockcount +
                        PREV.br_blockcount +
                        RIGHT.br_blockcount;
                break;

        case MASK3(LEFT_FILLING, RIGHT_FILLING, LEFT_CONTIG):
                /*
                 * Filling in all of a previously delayed allocation extent.
                 * The left neighbor is contiguous, the right is not.
                 */
                XFS_BMAP_TRACE_PRE_UPDATE("LF|RF|LC", ip, idx - 1,
                        XFS_DATA_FORK);
                xfs_bmbt_set_blockcount(xfs_iext_get_ext(ifp, idx - 1),
                        LEFT.br_blockcount + PREV.br_blockcount);
                XFS_BMAP_TRACE_POST_UPDATE("LF|RF|LC", ip, idx - 1,
                        XFS_DATA_FORK);
                ip->i_df.if_lastex = idx - 1;
                XFS_BMAP_TRACE_DELETE("LF|RF|LC", ip, idx, 1, XFS_DATA_FORK);
                xfs_iext_remove(ifp, idx, 1);
                if (cur == NULL)
                        rval = XFS_ILOG_DEXT;
                else {
                        rval = 0;
                        if ((error = xfs_bmbt_lookup_eq(cur, LEFT.br_startoff,
                                        LEFT.br_startblock, LEFT.br_blockcount,
                                        &i)))
                                goto done;
                        ASSERT(i == 1);
                        if ((error = xfs_bmbt_update(cur, LEFT.br_startoff,
                                        LEFT.br_startblock,
                                        LEFT.br_blockcount +
                                        PREV.br_blockcount, LEFT.br_state)))
                                goto done;
                }
                *dnew = 0;
                /* DELTA: Two in-core extents are replaced by one. */
                temp = LEFT.br_startoff;
                temp2 = LEFT.br_blockcount +
                        PREV.br_blockcount;
                break;

        case MASK3(LEFT_FILLING, RIGHT_FILLING, RIGHT_CONTIG):
                /*
                 * Filling in all of a previously delayed allocation extent.
                 * The right neighbor is contiguous, the left is not.
                 */
                XFS_BMAP_TRACE_PRE_UPDATE("LF|RF|RC", ip, idx, XFS_DATA_FORK);
                xfs_bmbt_set_startblock(ep, new->br_startblock);
                xfs_bmbt_set_blockcount(ep,
                        PREV.br_blockcount + RIGHT.br_blockcount);
                XFS_BMAP_TRACE_POST_UPDATE("LF|RF|RC", ip, idx, XFS_DATA_FORK);
                ip->i_df.if_lastex = idx;
                XFS_BMAP_TRACE_DELETE("LF|RF|RC", ip, idx + 1, 1, XFS_DATA_FORK);
                xfs_iext_remove(ifp, idx + 1, 1);
                if (cur == NULL)
                        rval = XFS_ILOG_DEXT;
                else {
                        rval = 0;
                        if ((error = xfs_bmbt_lookup_eq(cur, RIGHT.br_startoff,
                                        RIGHT.br_startblock,
                                        RIGHT.br_blockcount, &i)))
                                goto done;
                        ASSERT(i == 1);
                        if ((error = xfs_bmbt_update(cur, PREV.br_startoff,
                                        new->br_startblock,
                                        PREV.br_blockcount +
                                        RIGHT.br_blockcount, PREV.br_state)))
                                goto done;
                }
                *dnew = 0;
                /* DELTA: Two in-core extents are replaced by one. */
                temp = PREV.br_startoff;
                temp2 = PREV.br_blockcount +
                        RIGHT.br_blockcount;
                break;

        case MASK2(LEFT_FILLING, RIGHT_FILLING):
                /*
                 * Filling in all of a previously delayed allocation extent.
                 * Neither the left nor right neighbors are contiguous with
                 * the new one.
                 */
                XFS_BMAP_TRACE_PRE_UPDATE("LF|RF", ip, idx, XFS_DATA_FORK);
                xfs_bmbt_set_startblock(ep, new->br_startblock);
                XFS_BMAP_TRACE_POST_UPDATE("LF|RF", ip, idx, XFS_DATA_FORK);
                ip->i_df.if_lastex = idx;
                ip->i_d.di_nextents++;
                if (cur == NULL)
                        rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
                else {
                        rval = XFS_ILOG_CORE;
                        if ((error = xfs_bmbt_lookup_eq(cur, new->br_startoff,
                                        new->br_startblock, new->br_blockcount,
                                        &i)))
                                goto done;
                        ASSERT(i == 0);
                        cur->bc_rec.b.br_state = XFS_EXT_NORM;
                        if ((error = xfs_bmbt_insert(cur, &i)))
                                goto done;
                        ASSERT(i == 1);
                }
                *dnew = 0;
                /* DELTA: The in-core extent described by new changed type. */
                temp = new->br_startoff;
                temp2 = new->br_blockcount;
                break;

        case MASK2(LEFT_FILLING, LEFT_CONTIG):
                /*
                 * Filling in the first part of a previous delayed allocation.
                 * The left neighbor is contiguous.
                 */
                XFS_BMAP_TRACE_PRE_UPDATE("LF|LC", ip, idx - 1, XFS_DATA_FORK);
                xfs_bmbt_set_blockcount(xfs_iext_get_ext(ifp, idx - 1),
                        LEFT.br_blockcount + new->br_blockcount);
                xfs_bmbt_set_startoff(ep,
                        PREV.br_startoff + new->br_blockcount);
                XFS_BMAP_TRACE_POST_UPDATE("LF|LC", ip, idx - 1, XFS_DATA_FORK);
                temp = PREV.br_blockcount - new->br_blockcount;
                XFS_BMAP_TRACE_PRE_UPDATE("LF|LC", ip, idx, XFS_DATA_FORK);
                xfs_bmbt_set_blockcount(ep, temp);
                ip->i_df.if_lastex = idx - 1;
                if (cur == NULL)
                        rval = XFS_ILOG_DEXT;
                else {
                        rval = 0;
                        if ((error = xfs_bmbt_lookup_eq(cur, LEFT.br_startoff,
                                        LEFT.br_startblock, LEFT.br_blockcount,
                                        &i)))
                                goto done;
                        ASSERT(i == 1);
                        if ((error = xfs_bmbt_update(cur, LEFT.br_startoff,
                                        LEFT.br_startblock,
                                        LEFT.br_blockcount +
                                        new->br_blockcount,
                                        LEFT.br_state)))
                                goto done;
                }
                temp = XFS_FILBLKS_MIN(xfs_bmap_worst_indlen(ip, temp),
                        STARTBLOCKVAL(PREV.br_startblock));
                xfs_bmbt_set_startblock(ep, NULLSTARTBLOCK((int)temp));
                XFS_BMAP_TRACE_POST_UPDATE("LF|LC", ip, idx, XFS_DATA_FORK);
                *dnew = temp;
                /* DELTA: The boundary between two in-core extents moved. */
                temp = LEFT.br_startoff;
                temp2 = LEFT.br_blockcount +
                        PREV.br_blockcount;
                break;

        case MASK(LEFT_FILLING):
                /*
                 * Filling in the first part of a previous delayed allocation.
                 * The left neighbor is not contiguous.
                 */
                XFS_BMAP_TRACE_PRE_UPDATE("LF", ip, idx, XFS_DATA_FORK);
                xfs_bmbt_set_startoff(ep, new_endoff);
                temp = PREV.br_blockcount - new->br_blockcount;
                xfs_bmbt_set_blockcount(ep, temp);
                XFS_BMAP_TRACE_INSERT("LF", ip, idx, 1, new, NULL,
                        XFS_DATA_FORK);
                xfs_iext_insert(ifp, idx, 1, new);
                ip->i_df.if_lastex = idx;
                ip->i_d.di_nextents++;
                if (cur == NULL)
                        rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
                else {
                        rval = XFS_ILOG_CORE;
                        if ((error = xfs_bmbt_lookup_eq(cur, new->br_startoff,
                                        new->br_startblock, new->br_blockcount,
                                        &i)))
                                goto done;
                        ASSERT(i == 0);
                        cur->bc_rec.b.br_state = XFS_EXT_NORM;
                        if ((error = xfs_bmbt_insert(cur, &i)))
                                goto done;
                        ASSERT(i == 1);
                }
                if (ip->i_d.di_format == XFS_DINODE_FMT_EXTENTS &&
                    ip->i_d.di_nextents > ip->i_df.if_ext_max) {
                        error = xfs_bmap_extents_to_btree(ip->i_transp, ip,
                                        first, flist, &cur, 1, &tmp_rval,
                                        XFS_DATA_FORK);
                        rval |= tmp_rval;
                        if (error)
                                goto done;
                }
                temp = XFS_FILBLKS_MIN(xfs_bmap_worst_indlen(ip, temp),
                        STARTBLOCKVAL(PREV.br_startblock) -
                        (cur ? cur->bc_private.b.allocated : 0));
                ep = xfs_iext_get_ext(ifp, idx + 1);
                xfs_bmbt_set_startblock(ep, NULLSTARTBLOCK((int)temp));
                XFS_BMAP_TRACE_POST_UPDATE("LF", ip, idx + 1, XFS_DATA_FORK);
                *dnew = temp;
                /* DELTA: One in-core extent is split in two. */
                temp = PREV.br_startoff;
                temp2 = PREV.br_blockcount;
                break;

        case MASK2(RIGHT_FILLING, RIGHT_CONTIG):
                /*
                 * Filling in the last part of a previous delayed allocation.
                 * The right neighbor is contiguous with the new allocation.
                 */
                temp = PREV.br_blockcount - new->br_blockcount;
                XFS_BMAP_TRACE_PRE_UPDATE("RF|RC", ip, idx, XFS_DATA_FORK);
                XFS_BMAP_TRACE_PRE_UPDATE("RF|RC", ip, idx + 1, XFS_DATA_FORK);
                xfs_bmbt_set_blockcount(ep, temp);
                xfs_bmbt_set_allf(xfs_iext_get_ext(ifp, idx + 1),
                        new->br_startoff, new->br_startblock,
                        new->br_blockcount + RIGHT.br_blockcount,
                        RIGHT.br_state);
                XFS_BMAP_TRACE_POST_UPDATE("RF|RC", ip, idx + 1, XFS_DATA_FORK);
                ip->i_df.if_lastex = idx + 1;
                if (cur == NULL)
                        rval = XFS_ILOG_DEXT;
                else {
                        rval = 0;
                        if ((error = xfs_bmbt_lookup_eq(cur, RIGHT.br_startoff,
                                        RIGHT.br_startblock,
                                        RIGHT.br_blockcount, &i)))
                                goto done;
                        ASSERT(i == 1);
                        if ((error = xfs_bmbt_update(cur, new->br_startoff,
                                        new->br_startblock,
                                        new->br_blockcount +
                                        RIGHT.br_blockcount,
                                        RIGHT.br_state)))
                                goto done;
                }
                temp = XFS_FILBLKS_MIN(xfs_bmap_worst_indlen(ip, temp),
                        STARTBLOCKVAL(PREV.br_startblock));
                xfs_bmbt_set_startblock(ep, NULLSTARTBLOCK((int)temp));
                XFS_BMAP_TRACE_POST_UPDATE("RF|RC", ip, idx, XFS_DATA_FORK);
                *dnew = temp;
                /* DELTA: The boundary between two in-core extents moved. */
                temp = PREV.br_startoff;
                temp2 = PREV.br_blockcount +
                        RIGHT.br_blockcount;
                break;

        case MASK(RIGHT_FILLING):
                /*
                 * Filling in the last part of a previous delayed allocation.
                 * The right neighbor is not contiguous.
                 */
                temp = PREV.br_blockcount - new->br_blockcount;
                XFS_BMAP_TRACE_PRE_UPDATE("RF", ip, idx, XFS_DATA_FORK);
                xfs_bmbt_set_blockcount(ep, temp);
                XFS_BMAP_TRACE_INSERT("RF", ip, idx + 1, 1, new, NULL,
                        XFS_DATA_FORK);
                xfs_iext_insert(ifp, idx + 1, 1, new);
                ip->i_df.if_lastex = idx + 1;
                ip->i_d.di_nextents++;
                if (cur == NULL)
                        rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
                else {
                        rval = XFS_ILOG_CORE;
                        if ((error = xfs_bmbt_lookup_eq(cur, new->br_startoff,
                                        new->br_startblock, new->br_blockcount,
                                        &i)))
                                goto done;
                        ASSERT(i == 0);
                        cur->bc_rec.b.br_state = XFS_EXT_NORM;
                        if ((error = xfs_bmbt_insert(cur, &i)))
                                goto done;
                        ASSERT(i == 1);
                }
                if (ip->i_d.di_format == XFS_DINODE_FMT_EXTENTS &&
                    ip->i_d.di_nextents > ip->i_df.if_ext_max) {
                        error = xfs_bmap_extents_to_btree(ip->i_transp, ip,
                                first, flist, &cur, 1, &tmp_rval,
                                XFS_DATA_FORK);
                        rval |= tmp_rval;
                        if (error)
                                goto done;
                }
                temp = XFS_FILBLKS_MIN(xfs_bmap_worst_indlen(ip, temp),
                        STARTBLOCKVAL(PREV.br_startblock) -
                        (cur ? cur->bc_private.b.allocated : 0));
                ep = xfs_iext_get_ext(ifp, idx);
                xfs_bmbt_set_startblock(ep, NULLSTARTBLOCK((int)temp));
                XFS_BMAP_TRACE_POST_UPDATE("RF", ip, idx, XFS_DATA_FORK);
                *dnew = temp;
                /* DELTA: One in-core extent is split in two. */
                temp = PREV.br_startoff;
                temp2 = PREV.br_blockcount;
                break;

        case 0:
                /*
                 * Filling in the middle part of a previous delayed allocation.
                 * Contiguity is impossible here.
                 * This case is avoided almost all the time.
                 */
                temp = new->br_startoff - PREV.br_startoff;
                XFS_BMAP_TRACE_PRE_UPDATE("0", ip, idx, XFS_DATA_FORK);
                xfs_bmbt_set_blockcount(ep, temp);
                r[0] = *new;
                r[1].br_state = PREV.br_state;
                r[1].br_startblock = 0;
                r[1].br_startoff = new_endoff;
                temp2 = PREV.br_startoff + PREV.br_blockcount - new_endoff;
                r[1].br_blockcount = temp2;
                XFS_BMAP_TRACE_INSERT("0", ip, idx + 1, 2, &r[0], &r[1],
                        XFS_DATA_FORK);
                xfs_iext_insert(ifp, idx + 1, 2, &r[0]);
                ip->i_df.if_lastex = idx + 1;
                ip->i_d.di_nextents++;
                if (cur == NULL)
                        rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
                else {
                        rval = XFS_ILOG_CORE;
                        if ((error = xfs_bmbt_lookup_eq(cur, new->br_startoff,
                                        new->br_startblock, new->br_blockcount,
                                        &i)))
                                goto done;
                        ASSERT(i == 0);
                        cur->bc_rec.b.br_state = XFS_EXT_NORM;
                        if ((error = xfs_bmbt_insert(cur, &i)))
                                goto done;
                        ASSERT(i == 1);
                }
                if (ip->i_d.di_format == XFS_DINODE_FMT_EXTENTS &&
                    ip->i_d.di_nextents > ip->i_df.if_ext_max) {
                        error = xfs_bmap_extents_to_btree(ip->i_transp, ip,
                                        first, flist, &cur, 1, &tmp_rval,
                                        XFS_DATA_FORK);
                        rval |= tmp_rval;
                        if (error)
                                goto done;
                }
                temp = xfs_bmap_worst_indlen(ip, temp);
                temp2 = xfs_bmap_worst_indlen(ip, temp2);
                diff = (int)(temp + temp2 - STARTBLOCKVAL(PREV.br_startblock) -
                        (cur ? cur->bc_private.b.allocated : 0));
                if (diff > 0 &&
                    xfs_mod_incore_sb(ip->i_mount, XFS_SBS_FDBLOCKS, -((int64_t)diff), rsvd)) {
                        /*
                         * Ick gross gag me with a spoon.
                         */
                        ASSERT(0);      /* want to see if this ever happens! */
                        while (diff > 0) {
                                if (temp) {
                                        temp--;
                                        diff--;
                                        if (!diff ||
                                            !xfs_mod_incore_sb(ip->i_mount,
                                                    XFS_SBS_FDBLOCKS, -((int64_t)diff), rsvd))
                                                break;
                                }
                                if (temp2) {
                                        temp2--;
                                        diff--;
                                        if (!diff ||
                                            !xfs_mod_incore_sb(ip->i_mount,
                                                    XFS_SBS_FDBLOCKS, -((int64_t)diff), rsvd))
                                                break;
                                }
                        }
                }
                ep = xfs_iext_get_ext(ifp, idx);
                xfs_bmbt_set_startblock(ep, NULLSTARTBLOCK((int)temp));
                XFS_BMAP_TRACE_POST_UPDATE("0", ip, idx, XFS_DATA_FORK);
                XFS_BMAP_TRACE_PRE_UPDATE("0", ip, idx + 2, XFS_DATA_FORK);
                xfs_bmbt_set_startblock(xfs_iext_get_ext(ifp, idx + 2),
                        NULLSTARTBLOCK((int)temp2));
                XFS_BMAP_TRACE_POST_UPDATE("0", ip, idx + 2, XFS_DATA_FORK);
                *dnew = temp + temp2;
                /* DELTA: One in-core extent is split in three. */
                temp = PREV.br_startoff;
                temp2 = PREV.br_blockcount;
                break;

        case MASK3(LEFT_FILLING, LEFT_CONTIG, RIGHT_CONTIG):
        case MASK3(RIGHT_FILLING, LEFT_CONTIG, RIGHT_CONTIG):
        case MASK2(LEFT_FILLING, RIGHT_CONTIG):
        case MASK2(RIGHT_FILLING, LEFT_CONTIG):
        case MASK2(LEFT_CONTIG, RIGHT_CONTIG):
        case MASK(LEFT_CONTIG):
        case MASK(RIGHT_CONTIG):
                /*
                 * These cases are all impossible.
                 */
                ASSERT(0);
        }
        *curp = cur;
        if (delta) {
                temp2 += temp;
                if (delta->xed_startoff > temp)
                        delta->xed_startoff = temp;
                if (delta->xed_blockcount < temp2)
                        delta->xed_blockcount = temp2;
        }
done:
        *logflagsp = rval;
        return error;
#undef  LEFT
#undef  RIGHT
#undef  PREV
#undef  MASK
#undef  MASK2
#undef  MASK3
#undef  MASK4
#undef  STATE_SET
#undef  STATE_TEST
#undef  STATE_SET_TEST
#undef  SWITCH_STATE
}

/*
 * Called by xfs_bmap_add_extent to handle cases converting an unwritten
 * allocation to a real allocation or vice versa.
 */
STATIC int                              /* error */
xfs_bmap_add_extent_unwritten_real(
        xfs_inode_t             *ip,    /* incore inode pointer */
        xfs_extnum_t            idx,    /* extent number to update/insert */
        xfs_btree_cur_t         **curp, /* if *curp is null, not a btree */
        xfs_bmbt_irec_t         *new,   /* new data to add to file extents */
        int                     *logflagsp, /* inode logging flags */
        xfs_extdelta_t          *delta) /* Change made to incore extents */
{
        xfs_btree_cur_t         *cur;   /* btree cursor */
        xfs_bmbt_rec_host_t     *ep;    /* extent entry for idx */
        int                     error;  /* error return value */
        int                     i;      /* temp state */
        xfs_ifork_t             *ifp;   /* inode fork pointer */
        xfs_fileoff_t           new_endoff;     /* end offset of new entry */
        xfs_exntst_t            newext; /* new extent state */
        xfs_exntst_t            oldext; /* old extent state */
        xfs_bmbt_irec_t         r[3];   /* neighbor extent entries */
                                        /* left is 0, right is 1, prev is 2 */
        int                     rval=0; /* return value (logging flags) */
        int                     state = 0;/* state bits, accessed thru macros */
        xfs_filblks_t           temp=0;
        xfs_filblks_t           temp2=0;
        enum {                          /* bit number definitions for state */
                LEFT_CONTIG,    RIGHT_CONTIG,
                LEFT_FILLING,   RIGHT_FILLING,
                LEFT_DELAY,     RIGHT_DELAY,
                LEFT_VALID,     RIGHT_VALID
        };

#define LEFT            r[0]
#define RIGHT           r[1]
#define PREV            r[2]
#define MASK(b)         (1 << (b))
#define MASK2(a,b)      (MASK(a) | MASK(b))
#define MASK3(a,b,c)    (MASK2(a,b) | MASK(c))
#define MASK4(a,b,c,d)  (MASK3(a,b,c) | MASK(d))
#define STATE_SET(b,v)  ((v) ? (state |= MASK(b)) : (state &= ~MASK(b)))
#define STATE_TEST(b)   (state & MASK(b))
#define STATE_SET_TEST(b,v)     ((v) ? ((state |= MASK(b)), 1) : \
                                       ((state &= ~MASK(b)), 0))
#define SWITCH_STATE            \
        (state & MASK4(LEFT_FILLING, RIGHT_FILLING, LEFT_CONTIG, RIGHT_CONTIG))

        /*
         * Set up a bunch of variables to make the tests simpler.
         */
        error = 0;
        cur = *curp;
        ifp = XFS_IFORK_PTR(ip, XFS_DATA_FORK);
        ep = xfs_iext_get_ext(ifp, idx);
        xfs_bmbt_get_all(ep, &PREV);
        newext = new->br_state;
        oldext = (newext == XFS_EXT_UNWRITTEN) ?
                XFS_EXT_NORM : XFS_EXT_UNWRITTEN;
        ASSERT(PREV.br_state == oldext);
        new_endoff = new->br_startoff + new->br_blockcount;
        ASSERT(PREV.br_startoff <= new->br_startoff);
        ASSERT(PREV.br_startoff + PREV.br_blockcount >= new_endoff);
        /*
         * Set flags determining what part of the previous oldext allocation
         * extent is being replaced by a newext allocation.
         */
        STATE_SET(LEFT_FILLING, PREV.br_startoff == new->br_startoff);
        STATE_SET(RIGHT_FILLING,
                PREV.br_startoff + PREV.br_blockcount == new_endoff);
        /*
         * Check and set flags if this segment has a left neighbor.
         * Don't set contiguous if the combined extent would be too large.
         */
        if (STATE_SET_TEST(LEFT_VALID, idx > 0)) {
                xfs_bmbt_get_all(xfs_iext_get_ext(ifp, idx - 1), &LEFT);
                STATE_SET(LEFT_DELAY, ISNULLSTARTBLOCK(LEFT.br_startblock));
        }
        STATE_SET(LEFT_CONTIG,
                STATE_TEST(LEFT_VALID) && !STATE_TEST(LEFT_DELAY) &&
                LEFT.br_startoff + LEFT.br_blockcount == new->br_startoff &&
                LEFT.br_startblock + LEFT.br_blockcount == new->br_startblock &&
                LEFT.br_state == newext &&
                LEFT.br_blockcount + new->br_blockcount <= MAXEXTLEN);
        /*
         * Check and set flags if this segment has a right neighbor.
         * Don't set contiguous if the combined extent would be too large.
         * Also check for all-three-contiguous being too large.
         */
        if (STATE_SET_TEST(RIGHT_VALID,
                        idx <
                        ip->i_df.if_bytes / (uint)sizeof(xfs_bmbt_rec_t) - 1)) {
                xfs_bmbt_get_all(xfs_iext_get_ext(ifp, idx + 1), &RIGHT);
                STATE_SET(RIGHT_DELAY, ISNULLSTARTBLOCK(RIGHT.br_startblock));
        }
        STATE_SET(RIGHT_CONTIG,
                STATE_TEST(RIGHT_VALID) && !STATE_TEST(RIGHT_DELAY) &&
                new_endoff == RIGHT.br_startoff &&
                new->br_startblock + new->br_blockcount ==
                    RIGHT.br_startblock &&
                newext == RIGHT.br_state &&
                new->br_blockcount + RIGHT.br_blockcount <= MAXEXTLEN &&
                ((state & MASK3(LEFT_CONTIG, LEFT_FILLING, RIGHT_FILLING)) !=
                  MASK3(LEFT_CONTIG, LEFT_FILLING, RIGHT_FILLING) ||
                 LEFT.br_blockcount + new->br_blockcount + RIGHT.br_blockcount
                     <= MAXEXTLEN));
        /*
         * Switch out based on the FILLING and CONTIG state bits.
         */
        switch (SWITCH_STATE) {

        case MASK4(LEFT_FILLING, RIGHT_FILLING, LEFT_CONTIG, RIGHT_CONTIG):
                /*
                 * Setting all of a previous oldext extent to newext.
                 * The left and right neighbors are both contiguous with new.
                 */
                XFS_BMAP_TRACE_PRE_UPDATE("LF|RF|LC|RC", ip, idx - 1,
                        XFS_DATA_FORK);
                xfs_bmbt_set_blockcount(xfs_iext_get_ext(ifp, idx - 1),
                        LEFT.br_blockcount + PREV.br_blockcount +
                        RIGHT.br_blockcount);
                XFS_BMAP_TRACE_POST_UPDATE("LF|RF|LC|RC", ip, idx - 1,
                        XFS_DATA_FORK);
                XFS_BMAP_TRACE_DELETE("LF|RF|LC|RC", ip, idx, 2, XFS_DATA_FORK);
                xfs_iext_remove(ifp, idx, 2);
                ip->i_df.if_lastex = idx - 1;
                ip->i_d.di_nextents -= 2;
                if (cur == NULL)
                        rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
                else {
                        rval = XFS_ILOG_CORE;
                        if ((error = xfs_bmbt_lookup_eq(cur, RIGHT.br_startoff,
                                        RIGHT.br_startblock,
                                        RIGHT.br_blockcount, &i)))
                                goto done;
                        ASSERT(i == 1);
                        if ((error = xfs_bmbt_delete(cur, &i)))
                                goto done;
                        ASSERT(i == 1);
                        if ((error = xfs_bmbt_decrement(cur, 0, &i)))
                                goto done;
                        ASSERT(i == 1);
                        if ((error = xfs_bmbt_delete(cur, &i)))
                                goto done;
                        ASSERT(i == 1);
                        if ((error = xfs_bmbt_decrement(cur, 0, &i)))
                                goto done;
                        ASSERT(i == 1);
                        if ((error = xfs_bmbt_update(cur, LEFT.br_startoff,
                                LEFT.br_startblock,
                                LEFT.br_blockcount + PREV.br_blockcount +
                                RIGHT.br_blockcount, LEFT.br_state)))
                                goto done;
                }
                /* DELTA: Three in-core extents are replaced by one. */
                temp = LEFT.br_startoff;
                temp2 = LEFT.br_blockcount +
                        PREV.br_blockcount +
                        RIGHT.br_blockcount;
                break;

        case MASK3(LEFT_FILLING, RIGHT_FILLING, LEFT_CONTIG):
                /*
                 * Setting all of a previous oldext extent to newext.
                 * The left neighbor is contiguous, the right is not.
                 */
                XFS_BMAP_TRACE_PRE_UPDATE("LF|RF|LC", ip, idx - 1,
                        XFS_DATA_FORK);
                xfs_bmbt_set_blockcount(xfs_iext_get_ext(ifp, idx - 1),
                        LEFT.br_blockcount + PREV.br_blockcount);
                XFS_BMAP_TRACE_POST_UPDATE("LF|RF|LC", ip, idx - 1,
                        XFS_DATA_FORK);
                ip->i_df.if_lastex = idx - 1;
                XFS_BMAP_TRACE_DELETE("LF|RF|LC", ip, idx, 1, XFS_DATA_FORK);
                xfs_iext_remove(ifp, idx, 1);
                ip->i_d.di_nextents--;
                if (cur == NULL)
                        rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
                else {
                        rval = XFS_ILOG_CORE;
                        if ((error = xfs_bmbt_lookup_eq(cur, PREV.br_startoff,
                                        PREV.br_startblock, PREV.br_blockcount,
                                        &i)))
                                goto done;
                        ASSERT(i == 1);
                        if ((error = xfs_bmbt_delete(cur, &i)))
                                goto done;
                        ASSERT(i == 1);
                        if ((error = xfs_bmbt_decrement(cur, 0, &i)))
                                goto done;
                        ASSERT(i == 1);
                        if ((error = xfs_bmbt_update(cur, LEFT.br_startoff,
                                LEFT.br_startblock,
                                LEFT.br_blockcount + PREV.br_blockcount,
                                LEFT.br_state)))
                                goto done;
                }
                /* DELTA: Two in-core extents are replaced by one. */
                temp = LEFT.br_startoff;
                temp2 = LEFT.br_blockcount +
                        PREV.br_blockcount;
                break;

        case MASK3(LEFT_FILLING, RIGHT_FILLING, RIGHT_CONTIG):
                /*
                 * Setting all of a previous oldext extent to newext.
                 * The right neighbor is contiguous, the left is not.
                 */
                XFS_BMAP_TRACE_PRE_UPDATE("LF|RF|RC", ip, idx,
                        XFS_DATA_FORK);
                xfs_bmbt_set_blockcount(ep,
                        PREV.br_blockcount + RIGHT.br_blockcount);
                xfs_bmbt_set_state(ep, newext);
                XFS_BMAP_TRACE_POST_UPDATE("LF|RF|RC", ip, idx,
                        XFS_DATA_FORK);
                ip->i_df.if_lastex = idx;
                XFS_BMAP_TRACE_DELETE("LF|RF|RC", ip, idx + 1, 1, XFS_DATA_FORK);
                xfs_iext_remove(ifp, idx + 1, 1);
                ip->i_d.di_nextents--;
                if (cur == NULL)
                        rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
                else {
                        rval = XFS_ILOG_CORE;
                        if ((error = xfs_bmbt_lookup_eq(cur, RIGHT.br_startoff,
                                        RIGHT.br_startblock,
                                        RIGHT.br_blockcount, &i)))
                                goto done;
                        ASSERT(i == 1);
                        if ((error = xfs_bmbt_delete(cur, &i)))
                                goto done;
                        ASSERT(i == 1);
                        if ((error = xfs_bmbt_decrement(cur, 0, &i)))
                                goto done;
                        ASSERT(i == 1);
                        if ((error = xfs_bmbt_update(cur, new->br_startoff,
                                new->br_startblock,
                                new->br_blockcount + RIGHT.br_blockcount,
                                newext)))
                                goto done;
                }
                /* DELTA: Two in-core extents are replaced by one. */
                temp = PREV.br_startoff;
                temp2 = PREV.br_blockcount +
                        RIGHT.br_blockcount;
                break;

        case MASK2(LEFT_FILLING, RIGHT_FILLING):
                /*
                 * Setting all of a previous oldext extent to newext.
                 * Neither the left nor right neighbors are contiguous with
                 * the new one.
                 */
                XFS_BMAP_TRACE_PRE_UPDATE("LF|RF", ip, idx,
                        XFS_DATA_FORK);
                xfs_bmbt_set_state(ep, newext);
                XFS_BMAP_TRACE_POST_UPDATE("LF|RF", ip, idx,
                        XFS_DATA_FORK);
                ip->i_df.if_lastex = idx;
                if (cur == NULL)
                        rval = XFS_ILOG_DEXT;
                else {
                        rval = 0;
                        if ((error = xfs_bmbt_lookup_eq(cur, new->br_startoff,
                                        new->br_startblock, new->br_blockcount,
                                        &i)))
                                goto done;
                        ASSERT(i == 1);
                        if ((error = xfs_bmbt_update(cur, new->br_startoff,
                                new->br_startblock, new->br_blockcount,
                                newext)))
                                goto done;
                }
                /* DELTA: The in-core extent described by new changed type. */
                temp = new->br_startoff;
                temp2 = new->br_blockcount;
                break;

        case MASK2(LEFT_FILLING, LEFT_CONTIG):
                /*
                 * Setting the first part of a previous oldext extent to newext.
                 * The left neighbor is contiguous.
                 */
                XFS_BMAP_TRACE_PRE_UPDATE("LF|LC", ip, idx - 1,
                        XFS_DATA_FORK);
                xfs_bmbt_set_blockcount(xfs_iext_get_ext(ifp, idx - 1),
                        LEFT.br_blockcount + new->br_blockcount);
                xfs_bmbt_set_startoff(ep,
                        PREV.br_startoff + new->br_blockcount);
                XFS_BMAP_TRACE_POST_UPDATE("LF|LC", ip, idx - 1,
                        XFS_DATA_FORK);
                XFS_BMAP_TRACE_PRE_UPDATE("LF|LC", ip, idx,
                        XFS_DATA_FORK);
                xfs_bmbt_set_startblock(ep,
                        new->br_startblock + new->br_blockcount);
                xfs_bmbt_set_blockcount(ep,
                        PREV.br_blockcount - new->br_blockcount);
                XFS_BMAP_TRACE_POST_UPDATE("LF|LC", ip, idx,
                        XFS_DATA_FORK);
                ip->i_df.if_lastex = idx - 1;
                if (cur == NULL)
                        rval = XFS_ILOG_DEXT;
                else {
                        rval = 0;
                        if ((error = xfs_bmbt_lookup_eq(cur, PREV.br_startoff,
                                        PREV.br_startblock, PREV.br_blockcount,
                                        &i)))
                                goto done;
                        ASSERT(i == 1);
                        if ((error = xfs_bmbt_update(cur,
                                PREV.br_startoff + new->br_blockcount,
                                PREV.br_startblock + new->br_blockcount,
                                PREV.br_blockcount - new->br_blockcount,
                                oldext)))
                                goto done;
                        if ((error = xfs_bmbt_decrement(cur, 0, &i)))
                                goto done;
                        if (xfs_bmbt_update(cur, LEFT.br_startoff,
                                LEFT.br_startblock,
                                LEFT.br_blockcount + new->br_blockcount,
                                LEFT.br_state))
                                goto done;
                }
                /* DELTA: The boundary between two in-core extents moved. */
                temp = LEFT.br_startoff;
                temp2 = LEFT.br_blockcount +
                        PREV.br_blockcount;
                break;

        case MASK(LEFT_FILLING):
                /*
                 * Setting the first part of a previous oldext extent to newext.
                 * The left neighbor is not contiguous.
                 */
                XFS_BMAP_TRACE_PRE_UPDATE("LF", ip, idx, XFS_DATA_FORK);
                ASSERT(ep && xfs_bmbt_get_state(ep) == oldext);
                xfs_bmbt_set_startoff(ep, new_endoff);
                xfs_bmbt_set_blockcount(ep,
                        PREV.br_blockcount - new->br_blockcount);
                xfs_bmbt_set_startblock(ep,
                        new->br_startblock + new->br_blockcount);
                XFS_BMAP_TRACE_POST_UPDATE("LF", ip, idx, XFS_DATA_FORK);
                XFS_BMAP_TRACE_INSERT("LF", ip, idx, 1, new, NULL,
                        XFS_DATA_FORK);
                xfs_iext_insert(ifp, idx, 1, new);
                ip->i_df.if_lastex = idx;
                ip->i_d.di_nextents++;
                if (cur == NULL)
                        rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
                else {
                        rval = XFS_ILOG_CORE;
                        if ((error = xfs_bmbt_lookup_eq(cur, PREV.br_startoff,
                                        PREV.br_startblock, PREV.br_blockcount,
                                        &i)))
                                goto done;
                        ASSERT(i == 1);
                        if ((error = xfs_bmbt_update(cur,
                                PREV.br_startoff + new->br_blockcount,
                                PREV.br_startblock + new->br_blockcount,
                                PREV.br_blockcount - new->br_blockcount,
                                oldext)))
                                goto done;
                        cur->bc_rec.b = *new;
                        if ((error = xfs_bmbt_insert(cur, &i)))
                                goto done;
                        ASSERT(i == 1);
                }
                /* DELTA: One in-core extent is split in two. */
                temp = PREV.br_startoff;
                temp2 = PREV.br_blockcount;
                break;

        case MASK2(RIGHT_FILLING, RIGHT_CONTIG):
                /*
                 * Setting the last part of a previous oldext extent to newext.
                 * The right neighbor is contiguous with the new allocation.
                 */
                XFS_BMAP_TRACE_PRE_UPDATE("RF|RC", ip, idx,
                        XFS_DATA_FORK);
                XFS_BMAP_TRACE_PRE_UPDATE("RF|RC", ip, idx + 1,
                        XFS_DATA_FORK);
                xfs_bmbt_set_blockcount(ep,
                        PREV.br_blockcount - new->br_blockcount);
                XFS_BMAP_TRACE_POST_UPDATE("RF|RC", ip, idx,
                        XFS_DATA_FORK);
                xfs_bmbt_set_allf(xfs_iext_get_ext(ifp, idx + 1),
                        new->br_startoff, new->br_startblock,
                        new->br_blockcount + RIGHT.br_blockcount, newext);
                XFS_BMAP_TRACE_POST_UPDATE("RF|RC", ip, idx + 1,
                        XFS_DATA_FORK);
                ip->i_df.if_lastex = idx + 1;
                if (cur == NULL)
                        rval = XFS_ILOG_DEXT;
                else {
                        rval = 0;
                        if ((error = xfs_bmbt_lookup_eq(cur, PREV.br_startoff,
                                        PREV.br_startblock,
                                        PREV.br_blockcount, &i)))
                                goto done;
                        ASSERT(i == 1);
                        if ((error = xfs_bmbt_update(cur, PREV.br_startoff,
                                PREV.br_startblock,
                                PREV.br_blockcount - new->br_blockcount,
                                oldext)))
                                goto done;
                        if ((error = xfs_bmbt_increment(cur, 0, &i)))
                                goto done;
                        if ((error = xfs_bmbt_update(cur, new->br_startoff,
                                new->br_startblock,
                                new->br_blockcount + RIGHT.br_blockcount,
                                newext)))
                                goto done;
                }
                /* DELTA: The boundary between two in-core extents moved. */
                temp = PREV.br_startoff;
                temp2 = PREV.br_blockcount +
                        RIGHT.br_blockcount;
                break;

        case MASK(RIGHT_FILLING):
                /*
                 * Setting the last part of a previous oldext extent to newext.
                 * The right neighbor is not contiguous.
                 */
                XFS_BMAP_TRACE_PRE_UPDATE("RF", ip, idx, XFS_DATA_FORK);
                xfs_bmbt_set_blockcount(ep,
                        PREV.br_blockcount - new->br_blockcount);
                XFS_BMAP_TRACE_POST_UPDATE("RF", ip, idx, XFS_DATA_FORK);
                XFS_BMAP_TRACE_INSERT("RF", ip, idx + 1, 1, new, NULL,
                        XFS_DATA_FORK);
                xfs_iext_insert(ifp, idx + 1, 1, new);
                ip->i_df.if_lastex = idx + 1;
                ip->i_d.di_nextents++;
                if (cur == NULL)
                        rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
                else {
                        rval = XFS_ILOG_CORE;
                        if ((error = xfs_bmbt_lookup_eq(cur, PREV.br_startoff,
                                        PREV.br_startblock, PREV.br_blockcount,
                                        &i)))
                                goto done;
                        ASSERT(i == 1);
                        if ((error = xfs_bmbt_update(cur, PREV.br_startoff,
                                PREV.br_startblock,
                                PREV.br_blockcount - new->br_blockcount,
                                oldext)))
                                goto done;
                        if ((error = xfs_bmbt_lookup_eq(cur, new->br_startoff,
                                        new->br_startblock, new->br_blockcount,
                                        &i)))
                                goto done;
                        ASSERT(i == 0);
                        cur->bc_rec.b.br_state = XFS_EXT_NORM;
                        if ((error = xfs_bmbt_insert(cur, &i)))
                                goto done;
                        ASSERT(i == 1);
                }
                /* DELTA: One in-core extent is split in two. */
                temp = PREV.br_startoff;
                temp2 = PREV.br_blockcount;
                break;

        case 0:
                /*
                 * Setting the middle part of a previous oldext extent to
                 * newext.  Contiguity is impossible here.
                 * One extent becomes three extents.
                 */
                XFS_BMAP_TRACE_PRE_UPDATE("0", ip, idx, XFS_DATA_FORK);
                xfs_bmbt_set_blockcount(ep,
                        new->br_startoff - PREV.br_startoff);
                XFS_BMAP_TRACE_POST_UPDATE("0", ip, idx, XFS_DATA_FORK);
                r[0] = *new;
                r[1].br_startoff = new_endoff;
                r[1].br_blockcount =
                        PREV.br_startoff + PREV.br_blockcount - new_endoff;
                r[1].br_startblock = new->br_startblock + new->br_blockcount;
                r[1].br_state = oldext;
                XFS_BMAP_TRACE_INSERT("0", ip, idx + 1, 2, &r[0], &r[1],
                        XFS_DATA_FORK);
                xfs_iext_insert(ifp, idx + 1, 2, &r[0]);
                ip->i_df.if_lastex = idx + 1;
                ip->i_d.di_nextents += 2;
                if (cur == NULL)
                        rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
                else {
                        rval = XFS_ILOG_CORE;
                        if ((error = xfs_bmbt_lookup_eq(cur, PREV.br_startoff,
                                        PREV.br_startblock, PREV.br_blockcount,
                                        &i)))
                                goto done;
                        ASSERT(i == 1);
                        /* new right extent - oldext */
                        if ((error = xfs_bmbt_update(cur, r[1].br_startoff,
                                r[1].br_startblock, r[1].br_blockcount,
                                r[1].br_state)))
                                goto done;
                        /* new left extent - oldext */
                        PREV.br_blockcount =
                                new->br_startoff - PREV.br_startoff;
                        cur->bc_rec.b = PREV;
                        if ((error = xfs_bmbt_insert(cur, &i)))
                                goto done;
                        ASSERT(i == 1);
                        if ((error = xfs_bmbt_increment(cur, 0, &i)))
                                goto done;
                        ASSERT(i == 1);
                        /* new middle extent - newext */
                        cur->bc_rec.b = *new;
                        if ((error = xfs_bmbt_insert(cur, &i)))
                                goto done;
                        ASSERT(i == 1);
                }
                /* DELTA: One in-core extent is split in three. */
                temp = PREV.br_startoff;
                temp2 = PREV.br_blockcount;
                break;

        case MASK3(LEFT_FILLING, LEFT_CONTIG, RIGHT_CONTIG):
        case MASK3(RIGHT_FILLING, LEFT_CONTIG, RIGHT_CONTIG):
        case MASK2(LEFT_FILLING, RIGHT_CONTIG):
        case MASK2(RIGHT_FILLING, LEFT_CONTIG):
        case MASK2(LEFT_CONTIG, RIGHT_CONTIG):
        case MASK(LEFT_CONTIG):
        case MASK(RIGHT_CONTIG):
                /*
                 * These cases are all impossible.
                 */
                ASSERT(0);
        }
        *curp = cur;
        if (delta) {
                temp2 += temp;
                if (delta->xed_startoff > temp)
                        delta->xed_startoff = temp;
                if (delta->xed_blockcount < temp2)
                        delta->xed_blockcount = temp2;
        }
done:
        *logflagsp = rval;
        return error;
#undef  LEFT
#undef  RIGHT
#undef  PREV
#undef  MASK
#undef  MASK2
#undef  MASK3
#undef  MASK4
#undef  STATE_SET
#undef  STATE_TEST
#undef  STATE_SET_TEST
#undef  SWITCH_STATE
}

/*
 * Called by xfs_bmap_add_extent to handle cases converting a hole
 * to a delayed allocation.
 */
/*ARGSUSED*/
STATIC int                              /* error */
xfs_bmap_add_extent_hole_delay(
        xfs_inode_t             *ip,    /* incore inode pointer */
        xfs_extnum_t            idx,    /* extent number to update/insert */
        xfs_bmbt_irec_t         *new,   /* new data to add to file extents */
        int                     *logflagsp, /* inode logging flags */
        xfs_extdelta_t          *delta, /* Change made to incore extents */
        int                     rsvd)           /* OK to allocate reserved blocks */
{
        xfs_bmbt_rec_host_t     *ep;    /* extent record for idx */
        xfs_ifork_t             *ifp;   /* inode fork pointer */
        xfs_bmbt_irec_t         left;   /* left neighbor extent entry */
        xfs_filblks_t           newlen=0;       /* new indirect size */
        xfs_filblks_t           oldlen=0;       /* old indirect size */
        xfs_bmbt_irec_t         right;  /* right neighbor extent entry */
        int                     state;  /* state bits, accessed thru macros */
        xfs_filblks_t           temp=0; /* temp for indirect calculations */
        xfs_filblks_t           temp2=0;
        enum {                          /* bit number definitions for state */
                LEFT_CONTIG,    RIGHT_CONTIG,
                LEFT_DELAY,     RIGHT_DELAY,
                LEFT_VALID,     RIGHT_VALID
        };

#define MASK(b)                 (1 << (b))
#define MASK2(a,b)              (MASK(a) | MASK(b))
#define STATE_SET(b,v)          ((v) ? (state |= MASK(b)) : (state &= ~MASK(b)))
#define STATE_TEST(b)           (state & MASK(b))
#define STATE_SET_TEST(b,v)     ((v) ? ((state |= MASK(b)), 1) : \
                                       ((state &= ~MASK(b)), 0))
#define SWITCH_STATE            (state & MASK2(LEFT_CONTIG, RIGHT_CONTIG))

        ifp = XFS_IFORK_PTR(ip, XFS_DATA_FORK);
        ep = xfs_iext_get_ext(ifp, idx);
        state = 0;
        ASSERT(ISNULLSTARTBLOCK(new->br_startblock));
        /*
         * Check and set flags if this segment has a left neighbor
         */
        if (STATE_SET_TEST(LEFT_VALID, idx > 0)) {
                xfs_bmbt_get_all(xfs_iext_get_ext(ifp, idx - 1), &left);
                STATE_SET(LEFT_DELAY, ISNULLSTARTBLOCK(left.br_startblock));
        }
        /*
         * Check and set flags if the current (right) segment exists.
         * If it doesn't exist, we're converting the hole at end-of-file.
         */
        if (STATE_SET_TEST(RIGHT_VALID,
                           idx <
                           ip->i_df.if_bytes / (uint)sizeof(xfs_bmbt_rec_t))) {
                xfs_bmbt_get_all(ep, &right);
                STATE_SET(RIGHT_DELAY, ISNULLSTARTBLOCK(right.br_startblock));
        }
        /*
         * Set contiguity flags on the left and right neighbors.
         * Don't let extents get too large, even if the pieces are contiguous.
         */
        STATE_SET(LEFT_CONTIG,
                STATE_TEST(LEFT_VALID) && STATE_TEST(LEFT_DELAY) &&
                left.br_startoff + left.br_blockcount == new->br_startoff &&
                left.br_blockcount + new->br_blockcount <= MAXEXTLEN);
        STATE_SET(RIGHT_CONTIG,
                STATE_TEST(RIGHT_VALID) && STATE_TEST(RIGHT_DELAY) &&
                new->br_startoff + new->br_blockcount == right.br_startoff &&
                new->br_blockcount + right.br_blockcount <= MAXEXTLEN &&
                (!STATE_TEST(LEFT_CONTIG) ||
                 (left.br_blockcount + new->br_blockcount +
                     right.br_blockcount <= MAXEXTLEN)));
        /*
         * Switch out based on the contiguity flags.
         */
        switch (SWITCH_STATE) {

        case MASK2(LEFT_CONTIG, RIGHT_CONTIG):
                /*
                 * New allocation is contiguous with delayed allocations
                 * on the left and on the right.
                 * Merge all three into a single extent record.
                 */
                temp = left.br_blockcount + new->br_blockcount +
                        right.br_blockcount;
                XFS_BMAP_TRACE_PRE_UPDATE("LC|RC", ip, idx - 1,
                        XFS_DATA_FORK);
                xfs_bmbt_set_blockcount(xfs_iext_get_ext(ifp, idx - 1), temp);
                oldlen = STARTBLOCKVAL(left.br_startblock) +
                        STARTBLOCKVAL(new->br_startblock) +
                        STARTBLOCKVAL(right.br_startblock);
                newlen = xfs_bmap_worst_indlen(ip, temp);
                xfs_bmbt_set_startblock(xfs_iext_get_ext(ifp, idx - 1),
                        NULLSTARTBLOCK((int)newlen));
                XFS_BMAP_TRACE_POST_UPDATE("LC|RC", ip, idx - 1,
                        XFS_DATA_FORK);
                XFS_BMAP_TRACE_DELETE("LC|RC", ip, idx, 1, XFS_DATA_FORK);
                xfs_iext_remove(ifp, idx, 1);
                ip->i_df.if_lastex = idx - 1;
                /* DELTA: Two in-core extents were replaced by one. */
                temp2 = temp;
                temp = left.br_startoff;
                break;

        case MASK(LEFT_CONTIG):
                /*
                 * New allocation is contiguous with a delayed allocation
                 * on the left.
                 * Merge the new allocation with the left neighbor.
                 */
                temp = left.br_blockcount + new->br_blockcount;
                XFS_BMAP_TRACE_PRE_UPDATE("LC", ip, idx - 1,
                        XFS_DATA_FORK);
                xfs_bmbt_set_blockcount(xfs_iext_get_ext(ifp, idx - 1), temp);
                oldlen = STARTBLOCKVAL(left.br_startblock) +
                        STARTBLOCKVAL(new->br_startblock);
                newlen = xfs_bmap_worst_indlen(ip, temp);
                xfs_bmbt_set_startblock(xfs_iext_get_ext(ifp, idx - 1),
                        NULLSTARTBLOCK((int)newlen));
                XFS_BMAP_TRACE_POST_UPDATE("LC", ip, idx - 1,
                        XFS_DATA_FORK);
                ip->i_df.if_lastex = idx - 1;
                /* DELTA: One in-core extent grew into a hole. */
                temp2 = temp;
                temp = left.br_startoff;
                break;

        case MASK(RIGHT_CONTIG):
                /*
                 * New allocation is contiguous with a delayed allocation
                 * on the right.
                 * Merge the new allocation with the right neighbor.
                 */
                XFS_BMAP_TRACE_PRE_UPDATE("RC", ip, idx, XFS_DATA_FORK);
                temp = new->br_blockcount + right.br_blockcount;
                oldlen = STARTBLOCKVAL(new->br_startblock) +
                        STARTBLOCKVAL(right.br_startblock);
                newlen = xfs_bmap_worst_indlen(ip, temp);
                xfs_bmbt_set_allf(ep, new->br_startoff,
                        NULLSTARTBLOCK((int)newlen), temp, right.br_state);
                XFS_BMAP_TRACE_POST_UPDATE("RC", ip, idx, XFS_DATA_FORK);
                ip->i_df.if_lastex = idx;
                /* DELTA: One in-core extent grew into a hole. */
                temp2 = temp;
                temp = new->br_startoff;
                break;

        case 0:
                /*
                 * New allocation is not contiguous with another
                 * delayed allocation.
                 * Insert a new entry.
                 */
                oldlen = newlen = 0;
                XFS_BMAP_TRACE_INSERT("0", ip, idx, 1, new, NULL,
                        XFS_DATA_FORK);
                xfs_iext_insert(ifp, idx, 1, new);
                ip->i_df.if_lastex = idx;
                /* DELTA: A new in-core extent was added in a hole. */
                temp2 = new->br_blockcount;
                temp = new->br_startoff;
                break;
        }
        if (oldlen != newlen) {
                ASSERT(oldlen > newlen);
                xfs_mod_incore_sb(ip->i_mount, XFS_SBS_FDBLOCKS,
                        (int64_t)(oldlen - newlen), rsvd);
                /*
                 * Nothing to do for disk quota accounting here.
                 */
        }
        if (delta) {
                temp2 += temp;
                if (delta->xed_startoff > temp)
                        delta->xed_startoff = temp;
                if (delta->xed_blockcount < temp2)
                        delta->xed_blockcount = temp2;
        }
        *logflagsp = 0;
        return 0;
#undef  MASK
#undef  MASK2
#undef  STATE_SET
#undef  STATE_TEST
#undef  STATE_SET_TEST
#undef  SWITCH_STATE
}

/*
 * Called by xfs_bmap_add_extent to handle cases converting a hole
 * to a real allocation.
 */
STATIC int                              /* error */
xfs_bmap_add_extent_hole_real(
        xfs_inode_t             *ip,    /* incore inode pointer */
        xfs_extnum_t            idx,    /* extent number to update/insert */
        xfs_btree_cur_t         *cur,   /* if null, not a btree */
        xfs_bmbt_irec_t         *new,   /* new data to add to file extents */
        int                     *logflagsp, /* inode logging flags */
        xfs_extdelta_t          *delta, /* Change made to incore extents */
        int                     whichfork) /* data or attr fork */
{
        xfs_bmbt_rec_host_t     *ep;    /* pointer to extent entry ins. point */
        int                     error;  /* error return value */
        int                     i;      /* temp state */
        xfs_ifork_t             *ifp;   /* inode fork pointer */
        xfs_bmbt_irec_t         left;   /* left neighbor extent entry */
        xfs_bmbt_irec_t         right;  /* right neighbor extent entry */
        int                     rval=0; /* return value (logging flags) */
        int                     state;  /* state bits, accessed thru macros */
        xfs_filblks_t           temp=0;
        xfs_filblks_t           temp2=0;
        enum {                          /* bit number definitions for state */
                LEFT_CONTIG,    RIGHT_CONTIG,
                LEFT_DELAY,     RIGHT_DELAY,
                LEFT_VALID,     RIGHT_VALID
        };

#define MASK(b)                 (1 << (b))
#define MASK2(a,b)              (MASK(a) | MASK(b))
#define STATE_SET(b,v)          ((v) ? (state |= MASK(b)) : (state &= ~MASK(b)))
#define STATE_TEST(b)           (state & MASK(b))
#define STATE_SET_TEST(b,v)     ((v) ? ((state |= MASK(b)), 1) : \
                                       ((state &= ~MASK(b)), 0))
#define SWITCH_STATE            (state & MASK2(LEFT_CONTIG, RIGHT_CONTIG))

        ifp = XFS_IFORK_PTR(ip, whichfork);
        ASSERT(idx <= ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t));
        ep = xfs_iext_get_ext(ifp, idx);
        state = 0;
        /*
         * Check and set flags if this segment has a left neighbor.
         */
        if (STATE_SET_TEST(LEFT_VALID, idx > 0)) {
                xfs_bmbt_get_all(xfs_iext_get_ext(ifp, idx - 1), &left);
                STATE_SET(LEFT_DELAY, ISNULLSTARTBLOCK(left.br_startblock));
        }
        /*
         * Check and set flags if this segment has a current value.
         * Not true if we're inserting into the "hole" at eof.
         */
        if (STATE_SET_TEST(RIGHT_VALID,
                           idx <
                           ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t))) {
                xfs_bmbt_get_all(ep, &right);
                STATE_SET(RIGHT_DELAY, ISNULLSTARTBLOCK(right.br_startblock));
        }
        /*
         * We're inserting a real allocation between "left" and "right".
         * Set the contiguity flags.  Don't let extents get too large.
         */
        STATE_SET(LEFT_CONTIG,
                STATE_TEST(LEFT_VALID) && !STATE_TEST(LEFT_DELAY) &&
                left.br_startoff + left.br_blockcount == new->br_startoff &&
                left.br_startblock + left.br_blockcount == new->br_startblock &&
                left.br_state == new->br_state &&
                left.br_blockcount + new->br_blockcount <= MAXEXTLEN);
        STATE_SET(RIGHT_CONTIG,
                STATE_TEST(RIGHT_VALID) && !STATE_TEST(RIGHT_DELAY) &&
                new->br_startoff + new->br_blockcount == right.br_startoff &&
                new->br_startblock + new->br_blockcount ==
                    right.br_startblock &&
                new->br_state == right.br_state &&
                new->br_blockcount + right.br_blockcount <= MAXEXTLEN &&
                (!STATE_TEST(LEFT_CONTIG) ||
                 left.br_blockcount + new->br_blockcount +
                     right.br_blockcount <= MAXEXTLEN));

        error = 0;
        /*
         * Select which case we're in here, and implement it.
         */
        switch (SWITCH_STATE) {

        case MASK2(LEFT_CONTIG, RIGHT_CONTIG):
                /*
                 * New allocation is contiguous with real allocations on the
                 * left and on the right.
                 * Merge all three into a single extent record.
                 */
                XFS_BMAP_TRACE_PRE_UPDATE("LC|RC", ip, idx - 1,
                        whichfork);
                xfs_bmbt_set_blockcount(xfs_iext_get_ext(ifp, idx - 1),
                        left.br_blockcount + new->br_blockcount +
                        right.br_blockcount);
                XFS_BMAP_TRACE_POST_UPDATE("LC|RC", ip, idx - 1,
                        whichfork);
                XFS_BMAP_TRACE_DELETE("LC|RC", ip, idx, 1, whichfork);
                xfs_iext_remove(ifp, idx, 1);
                ifp->if_lastex = idx - 1;
                XFS_IFORK_NEXT_SET(ip, whichfork,
                        XFS_IFORK_NEXTENTS(ip, whichfork) - 1);
                if (cur == NULL) {
                        rval = XFS_ILOG_CORE | XFS_ILOG_FEXT(whichfork);
                } else {
                        rval = XFS_ILOG_CORE;
                        if ((error = xfs_bmbt_lookup_eq(cur,
                                        right.br_startoff,
                                        right.br_startblock,
                                        right.br_blockcount, &i)))
                                goto done;
                        ASSERT(i == 1);
                        if ((error = xfs_bmbt_delete(cur, &i)))
                                goto done;
                        ASSERT(i == 1);
                        if ((error = xfs_bmbt_decrement(cur, 0, &i)))
                                goto done;
                        ASSERT(i == 1);
                        if ((error = xfs_bmbt_update(cur, left.br_startoff,
                                        left.br_startblock,
                                        left.br_blockcount +
                                                new->br_blockcount +
                                                right.br_blockcount,
                                        left.br_state)))
                                goto done;
                }
                /* DELTA: Two in-core extents were replaced by one. */
                temp = left.br_startoff;
                temp2 = left.br_blockcount +
                        new->br_blockcount +
                        right.br_blockcount;
                break;

        case MASK(LEFT_CONTIG):
                /*
                 * New allocation is contiguous with a real allocation
                 * on the left.
                 * Merge the new allocation with the left neighbor.
                 */
                XFS_BMAP_TRACE_PRE_UPDATE("LC", ip, idx - 1, whichfork);
                xfs_bmbt_set_blockcount(xfs_iext_get_ext(ifp, idx - 1),
                        left.br_blockcount + new->br_blockcount);
                XFS_BMAP_TRACE_POST_UPDATE("LC", ip, idx - 1, whichfork);
                ifp->if_lastex = idx - 1;
                if (cur == NULL) {
                        rval = XFS_ILOG_FEXT(whichfork);
                } else {
                        rval = 0;
                        if ((error = xfs_bmbt_lookup_eq(cur,
                                        left.br_startoff,
                                        left.br_startblock,
                                        left.br_blockcount, &i)))
                                goto done;
                        ASSERT(i == 1);
                        if ((error = xfs_bmbt_update(cur, left.br_startoff,
                                        left.br_startblock,
                                        left.br_blockcount +
                                                new->br_blockcount,
                                        left.br_state)))
                                goto done;
                }
                /* DELTA: One in-core extent grew. */
                temp = left.br_startoff;
                temp2 = left.br_blockcount +
                        new->br_blockcount;
                break;

        case MASK(RIGHT_CONTIG):
                /*
                 * New allocation is contiguous with a real allocation
                 * on the right.
                 * Merge the new allocation with the right neighbor.
                 */
                XFS_BMAP_TRACE_PRE_UPDATE("RC", ip, idx, whichfork);
                xfs_bmbt_set_allf(ep, new->br_startoff, new->br_startblock,
                        new->br_blockcount + right.br_blockcount,
                        right.br_state);
                XFS_BMAP_TRACE_POST_UPDATE("RC", ip, idx, whichfork);
                ifp->if_lastex = idx;
                if (cur == NULL) {
                        rval = XFS_ILOG_FEXT(whichfork);
                } else {
                        rval = 0;
                        if ((error = xfs_bmbt_lookup_eq(cur,
                                        right.br_startoff,
                                        right.br_startblock,
                                        right.br_blockcount, &i)))
                                goto done;
                        ASSERT(i == 1);
                        if ((error = xfs_bmbt_update(cur, new->br_startoff,
                                        new->br_startblock,
                                        new->br_blockcount +
                                                right.br_blockcount,
                                        right.br_state)))
                                goto done;
                }
                /* DELTA: One in-core extent grew. */
                temp = new->br_startoff;
                temp2 = new->br_blockcount +
                        right.br_blockcount;
                break;

        case 0:
                /*
                 * New allocation is not contiguous with another
                 * real allocation.
                 * Insert a new entry.
                 */
                XFS_BMAP_TRACE_INSERT("0", ip, idx, 1, new, NULL, whichfork);
                xfs_iext_insert(ifp, idx, 1, new);
                ifp->if_lastex = idx;
                XFS_IFORK_NEXT_SET(ip, whichfork,
                        XFS_IFORK_NEXTENTS(ip, whichfork) + 1);
                if (cur == NULL) {
                        rval = XFS_ILOG_CORE | XFS_ILOG_FEXT(whichfork);
                } else {
                        rval = XFS_ILOG_CORE;
                        if ((error = xfs_bmbt_lookup_eq(cur,
                                        new->br_startoff,
                                        new->br_startblock,
                                        new->br_blockcount, &i)))
                                goto done;
                        ASSERT(i == 0);
                        cur->bc_rec.b.br_state = new->br_state;
                        if ((error = xfs_bmbt_insert(cur, &i)))
                                goto done;
                        ASSERT(i == 1);
                }
                /* DELTA: A new extent was added in a hole. */
                temp = new->br_startoff;
                temp2 = new->br_blockcount;
                break;
        }
        if (delta) {
                temp2 += temp;
                if (delta->xed_startoff > temp)
                        delta->xed_startoff = temp;
                if (delta->xed_blockcount < temp2)
                        delta->xed_blockcount = temp2;
        }
done:
        *logflagsp = rval;
        return error;
#undef  MASK
#undef  MASK2
#undef  STATE_SET
#undef  STATE_TEST
#undef  STATE_SET_TEST
#undef  SWITCH_STATE
}

/*
 * Adjust the size of the new extent based on di_extsize and rt extsize.
 */
STATIC int
xfs_bmap_extsize_align(
        xfs_mount_t     *mp,
        xfs_bmbt_irec_t *gotp,          /* next extent pointer */
        xfs_bmbt_irec_t *prevp,         /* previous extent pointer */
        xfs_extlen_t    extsz,          /* align to this extent size */
        int             rt,             /* is this a realtime inode? */
        int             eof,            /* is extent at end-of-file? */
        int             delay,          /* creating delalloc extent? */
        int             convert,        /* overwriting unwritten extent? */
        xfs_fileoff_t   *offp,          /* in/out: aligned offset */
        xfs_extlen_t    *lenp)          /* in/out: aligned length */
{
        xfs_fileoff_t   orig_off;       /* original offset */
        xfs_extlen_t    orig_alen;      /* original length */
        xfs_fileoff_t   orig_end;       /* original off+len */
        xfs_fileoff_t   nexto;          /* next file offset */
        xfs_fileoff_t   prevo;          /* previous file offset */
        xfs_fileoff_t   align_off;      /* temp for offset */
        xfs_extlen_t    align_alen;     /* temp for length */
        xfs_extlen_t    temp;           /* temp for calculations */

        if (convert)
                return 0;

        orig_off = align_off = *offp;
        orig_alen = align_alen = *lenp;
        orig_end = orig_off + orig_alen;

        /*
         * If this request overlaps an existing extent, then don't
         * attempt to perform any additional alignment.
         */
        if (!delay && !eof &&
            (orig_off >= gotp->br_startoff) &&
            (orig_end <= gotp->br_startoff + gotp->br_blockcount)) {
                return 0;
        }

        /*
         * If the file offset is unaligned vs. the extent size
         * we need to align it.  This will be possible unless
         * the file was previously written with a kernel that didn't
         * perform this alignment, or if a truncate shot us in the
         * foot.
         */
        temp = do_mod(orig_off, extsz);
        if (temp) {
                align_alen += temp;
                align_off -= temp;
        }
        /*
         * Same adjustment for the end of the requested area.
         */
        if ((temp = (align_alen % extsz))) {
                align_alen += extsz - temp;
        }
        /*
         * If the previous block overlaps with this proposed allocation
         * then move the start forward without adjusting the length.
         */
        if (prevp->br_startoff != NULLFILEOFF) {
                if (prevp->br_startblock == HOLESTARTBLOCK)
                        prevo = prevp->br_startoff;
                else
                        prevo = prevp->br_startoff + prevp->br_blockcount;
        } else
                prevo = 0;
        if (align_off != orig_off && align_off < prevo)
                align_off = prevo;
        /*
         * If the next block overlaps with this proposed allocation
         * then move the start back without adjusting the length,
         * but not before offset 0.
         * This may of course make the start overlap previous block,
         * and if we hit the offset 0 limit then the next block
         * can still overlap too.
         */
        if (!eof && gotp->br_startoff != NULLFILEOFF) {
                if ((delay && gotp->br_startblock == HOLESTARTBLOCK) ||
                    (!delay && gotp->br_startblock == DELAYSTARTBLOCK))
                        nexto = gotp->br_startoff + gotp->br_blockcount;
                else
                        nexto = gotp->br_startoff;
        } else
                nexto = NULLFILEOFF;
        if (!eof &&
            align_off + align_alen != orig_end &&
            align_off + align_alen > nexto)
                align_off = nexto > align_alen ? nexto - align_alen : 0;
        /*
         * If we're now overlapping the next or previous extent that
         * means we can't fit an extsz piece in this hole.  Just move
         * the start forward to the first valid spot and set
         * the length so we hit the end.
         */
        if (align_off != orig_off && align_off < prevo)
                align_off = prevo;
        if (align_off + align_alen != orig_end &&
            align_off + align_alen > nexto &&
            nexto != NULLFILEOFF) {
                ASSERT(nexto > prevo);
                align_alen = nexto - align_off;
        }

        /*
         * If realtime, and the result isn't a multiple of the realtime
         * extent size we need to remove blocks until it is.
         */
        if (rt && (temp = (align_alen % mp->m_sb.sb_rextsize))) {
                /*
                 * We're not covering the original request, or
                 * we won't be able to once we fix the length.
                 */
                if (orig_off < align_off ||
                    orig_end > align_off + align_alen ||
                    align_alen - temp < orig_alen)
                        return XFS_ERROR(EINVAL);
                /*
                 * Try to fix it by moving the start up.
                 */
                if (align_off + temp <= orig_off) {
                        align_alen -= temp;
                        align_off += temp;
                }
                /*
                 * Try to fix it by moving the end in.
                 */
                else if (align_off + align_alen - temp >= orig_end)
                        align_alen -= temp;
                /*
                 * Set the start to the minimum then trim the length.
                 */
                else {
                        align_alen -= orig_off - align_off;
                        align_off = orig_off;
                        align_alen -= align_alen % mp->m_sb.sb_rextsize;
                }
                /*
                 * Result doesn't cover the request, fail it.
                 */
                if (orig_off < align_off || orig_end > align_off + align_alen)
                        return XFS_ERROR(EINVAL);
        } else {
                ASSERT(orig_off >= align_off);
                ASSERT(orig_end <= align_off + align_alen);
        }

#ifdef DEBUG
        if (!eof && gotp->br_startoff != NULLFILEOFF)
                ASSERT(align_off + align_alen <= gotp->br_startoff);
        if (prevp->br_startoff != NULLFILEOFF)
                ASSERT(align_off >= prevp->br_startoff + prevp->br_blockcount);
#endif

        *lenp = align_alen;
        *offp = align_off;
        return 0;
}

#define XFS_ALLOC_GAP_UNITS     4

STATIC int
xfs_bmap_adjacent(
        xfs_bmalloca_t  *ap)            /* bmap alloc argument struct */
{
        xfs_fsblock_t   adjust;         /* adjustment to block numbers */
        xfs_agnumber_t  fb_agno;        /* ag number of ap->firstblock */
        xfs_mount_t     *mp;            /* mount point structure */
        int             nullfb;         /* true if ap->firstblock isn't set */
        int             rt;             /* true if inode is realtime */

#define ISVALID(x,y)    \
        (rt ? \
                (x) < mp->m_sb.sb_rblocks : \
                XFS_FSB_TO_AGNO(mp, x) == XFS_FSB_TO_AGNO(mp, y) && \
                XFS_FSB_TO_AGNO(mp, x) < mp->m_sb.sb_agcount && \
                XFS_FSB_TO_AGBNO(mp, x) < mp->m_sb.sb_agblocks)

        mp = ap->ip->i_mount;
        nullfb = ap->firstblock == NULLFSBLOCK;
        rt = XFS_IS_REALTIME_INODE(ap->ip) && ap->userdata;
        fb_agno = nullfb ? NULLAGNUMBER : XFS_FSB_TO_AGNO(mp, ap->firstblock);
        /*
         * If allocating at eof, and there's a previous real block,
         * try to use it's last block as our starting point.
         */
        if (ap->eof && ap->prevp->br_startoff != NULLFILEOFF &&
            !ISNULLSTARTBLOCK(ap->prevp->br_startblock) &&
            ISVALID(ap->prevp->br_startblock + ap->prevp->br_blockcount,
                    ap->prevp->br_startblock)) {
                ap->rval = ap->prevp->br_startblock + ap->prevp->br_blockcount;
                /*
                 * Adjust for the gap between prevp and us.
                 */
                adjust = ap->off -
                        (ap->prevp->br_startoff + ap->prevp->br_blockcount);
                if (adjust &&
                    ISVALID(ap->rval + adjust, ap->prevp->br_startblock))
                        ap->rval += adjust;
        }
        /*
         * If not at eof, then compare the two neighbor blocks.
         * Figure out whether either one gives us a good starting point,
         * and pick the better one.
         */
        else if (!ap->eof) {
                xfs_fsblock_t   gotbno;         /* right side block number */
                xfs_fsblock_t   gotdiff=0;      /* right side difference */
                xfs_fsblock_t   prevbno;        /* left side block number */
                xfs_fsblock_t   prevdiff=0;     /* left side difference */

                /*
                 * If there's a previous (left) block, select a requested
                 * start block based on it.
                 */
                if (ap->prevp->br_startoff != NULLFILEOFF &&
                    !ISNULLSTARTBLOCK(ap->prevp->br_startblock) &&
                    (prevbno = ap->prevp->br_startblock +
                               ap->prevp->br_blockcount) &&
                    ISVALID(prevbno, ap->prevp->br_startblock)) {
                        /*
                         * Calculate gap to end of previous block.
                         */
                        adjust = prevdiff = ap->off -
                                (ap->prevp->br_startoff +
                                 ap->prevp->br_blockcount);
                        /*
                         * Figure the startblock based on the previous block's
                         * end and the gap size.
                         * Heuristic!
                         * If the gap is large relative to the piece we're
                         * allocating, or using it gives us an invalid block
                         * number, then just use the end of the previous block.
                         */
                        if (prevdiff <= XFS_ALLOC_GAP_UNITS * ap->alen &&
                            ISVALID(prevbno + prevdiff,
                                    ap->prevp->br_startblock))
                                prevbno += adjust;
                        else
                                prevdiff += adjust;
                        /*
                         * If the firstblock forbids it, can't use it,
                         * must use default.
                         */
                        if (!rt && !nullfb &&
                            XFS_FSB_TO_AGNO(mp, prevbno) != fb_agno)
                                prevbno = NULLFSBLOCK;
                }
                /*
                 * No previous block or can't follow it, just default.
                 */
                else
                        prevbno = NULLFSBLOCK;
                /*
                 * If there's a following (right) block, select a requested
                 * start block based on it.
                 */
                if (!ISNULLSTARTBLOCK(ap->gotp->br_startblock)) {
                        /*
                         * Calculate gap to start of next block.
                         */
                        adjust = gotdiff = ap->gotp->br_startoff - ap->off;
                        /*
                         * Figure the startblock based on the next block's
                         * start and the gap size.
                         */
                        gotbno = ap->gotp->br_startblock;
                        /*
                         * Heuristic!
                         * If the gap is large relative to the piece we're
                         * allocating, or using it gives us an invalid block
                         * number, then just use the start of the next block
                         * offset by our length.
                         */
                        if (gotdiff <= XFS_ALLOC_GAP_UNITS * ap->alen &&
                            ISVALID(gotbno - gotdiff, gotbno))
                                gotbno -= adjust;
                        else if (ISVALID(gotbno - ap->alen, gotbno)) {
                                gotbno -= ap->alen;
                                gotdiff += adjust - ap->alen;
                        } else
                                gotdiff += adjust;
                        /*
                         * If the firstblock forbids it, can't use it,
                         * must use default.
                         */
                        if (!rt && !nullfb &&
                            XFS_FSB_TO_AGNO(mp, gotbno) != fb_agno)
                                gotbno = NULLFSBLOCK;
                }
                /*
                 * No next block, just default.
                 */
                else
                        gotbno = NULLFSBLOCK;
                /*
                 * If both valid, pick the better one, else the only good
                 * one, else ap->rval is already set (to 0 or the inode block).
                 */
                if (prevbno != NULLFSBLOCK && gotbno != NULLFSBLOCK)
                        ap->rval = prevdiff <= gotdiff ? prevbno : gotbno;
                else if (prevbno != NULLFSBLOCK)
                        ap->rval = prevbno;
                else if (gotbno != NULLFSBLOCK)
                        ap->rval = gotbno;
        }
#undef ISVALID
        return 0;
}

STATIC int
xfs_bmap_rtalloc(
        xfs_bmalloca_t  *ap)            /* bmap alloc argument struct */
{
        xfs_alloctype_t atype = 0;      /* type for allocation routines */
        int             error;          /* error return value */
        xfs_mount_t     *mp;            /* mount point structure */
        xfs_extlen_t    prod = 0;       /* product factor for allocators */
        xfs_extlen_t    ralen = 0;      /* realtime allocation length */
        xfs_extlen_t    align;          /* minimum allocation alignment */
        xfs_rtblock_t   rtb;

        mp = ap->ip->i_mount;
        align = xfs_get_extsz_hint(ap->ip);
        prod = align / mp->m_sb.sb_rextsize;
        error = xfs_bmap_extsize_align(mp, ap->gotp, ap->prevp,
                                        align, 1, ap->eof, 0,
                                        ap->conv, &ap->off, &ap->alen);
        if (error)
                return error;
        ASSERT(ap->alen);
        ASSERT(ap->alen % mp->m_sb.sb_rextsize == 0);

        /*
         * If the offset & length are not perfectly aligned
         * then kill prod, it will just get us in trouble.
         */
        if (do_mod(ap->off, align) || ap->alen % align)
                prod = 1;
        /*
         * Set ralen to be the actual requested length in rtextents.
         */
        ralen = ap->alen / mp->m_sb.sb_rextsize;
        /*
         * If the old value was close enough to MAXEXTLEN that
         * we rounded up to it, cut it back so it's valid again.
         * Note that if it's a really large request (bigger than
         * MAXEXTLEN), we don't hear about that number, and can't
         * adjust the starting point to match it.
         */
        if (ralen * mp->m_sb.sb_rextsize >= MAXEXTLEN)
                ralen = MAXEXTLEN / mp->m_sb.sb_rextsize;
        /*
         * If it's an allocation to an empty file at offset 0,
         * pick an extent that will space things out in the rt area.
         */
        if (ap->eof && ap->off == 0) {
                xfs_rtblock_t uninitialized_var(rtx); /* realtime extent no */

                error = xfs_rtpick_extent(mp, ap->tp, ralen, &rtx);
                if (error)
                        return error;
                ap->rval = rtx * mp->m_sb.sb_rextsize;
        } else {
                ap->rval = 0;
        }

        xfs_bmap_adjacent(ap);

        /*
         * Realtime allocation, done through xfs_rtallocate_extent.
         */
        atype = ap->rval == 0 ?  XFS_ALLOCTYPE_ANY_AG : XFS_ALLOCTYPE_NEAR_BNO;
        do_div(ap->rval, mp->m_sb.sb_rextsize);
        rtb = ap->rval;
        ap->alen = ralen;
        if ((error = xfs_rtallocate_extent(ap->tp, ap->rval, 1, ap->alen,
                                &ralen, atype, ap->wasdel, prod, &rtb)))
                return error;
        if (rtb == NULLFSBLOCK && prod > 1 &&
            (error = xfs_rtallocate_extent(ap->tp, ap->rval, 1,
                                           ap->alen, &ralen, atype,
                                           ap->wasdel, 1, &rtb)))
                return error;
        ap->rval = rtb;
        if (ap->rval != NULLFSBLOCK) {
                ap->rval *= mp->m_sb.sb_rextsize;
                ralen *= mp->m_sb.sb_rextsize;
                ap->alen = ralen;
                ap->ip->i_d.di_nblocks += ralen;
                xfs_trans_log_inode(ap->tp, ap->ip, XFS_ILOG_CORE);
                if (ap->wasdel)
                        ap->ip->i_delayed_blks -= ralen;
                /*
                 * Adjust the disk quota also. This was reserved
                 * earlier.
                 */
                XFS_TRANS_MOD_DQUOT_BYINO(mp, ap->tp, ap->ip,
                        ap->wasdel ? XFS_TRANS_DQ_DELRTBCOUNT :
                                        XFS_TRANS_DQ_RTBCOUNT, (long) ralen);
        } else {
                ap->alen = 0;
        }
        return 0;
}

STATIC int
xfs_bmap_btalloc(
        xfs_bmalloca_t  *ap)            /* bmap alloc argument struct */
{
        xfs_mount_t     *mp;            /* mount point structure */
        xfs_alloctype_t atype = 0;      /* type for allocation routines */
        xfs_extlen_t    align;          /* minimum allocation alignment */
        xfs_agnumber_t  ag;
        xfs_agnumber_t  fb_agno;        /* ag number of ap->firstblock */
        xfs_agnumber_t  startag;
        xfs_alloc_arg_t args;
        xfs_extlen_t    blen;
        xfs_extlen_t    delta;
        xfs_extlen_t    longest;
        xfs_extlen_t    need;
        xfs_extlen_t    nextminlen = 0;
        xfs_perag_t     *pag;
        int             nullfb;         /* true if ap->firstblock isn't set */
        int             isaligned;
        int             notinit;
        int             tryagain;
        int             error;

        mp = ap->ip->i_mount;
        align = ap->userdata ? xfs_get_extsz_hint(ap->ip) : 0;
        if (unlikely(align)) {
                error = xfs_bmap_extsize_align(mp, ap->gotp, ap->prevp,
                                                align, 0, ap->eof, 0, ap->conv,
                                                &ap->off, &ap->alen);
                ASSERT(!error);
                ASSERT(ap->alen);
        }
        nullfb = ap->firstblock == NULLFSBLOCK;
        fb_agno = nullfb ? NULLAGNUMBER : XFS_FSB_TO_AGNO(mp, ap->firstblock);
        if (nullfb) {
                if (ap->userdata && xfs_inode_is_filestream(ap->ip)) {
                        ag = xfs_filestream_lookup_ag(ap->ip);
                        ag = (ag != NULLAGNUMBER) ? ag : 0;
                        ap->rval = XFS_AGB_TO_FSB(mp, ag, 0);
                } else {
                        ap->rval = XFS_INO_TO_FSB(mp, ap->ip->i_ino);
                }
        } else
                ap->rval = ap->firstblock;

        xfs_bmap_adjacent(ap);

        /*
         * If allowed, use ap->rval; otherwise must use firstblock since
         * it's in the right allocation group.
         */
        if (nullfb || XFS_FSB_TO_AGNO(mp, ap->rval) == fb_agno)
                ;
        else
                ap->rval = ap->firstblock;
        /*
         * Normal allocation, done through xfs_alloc_vextent.
         */
        tryagain = isaligned = 0;
        args.tp = ap->tp;
        args.mp = mp;
        args.fsbno = ap->rval;
        args.maxlen = MIN(ap->alen, mp->m_sb.sb_agblocks);
        args.firstblock = ap->firstblock;
        blen = 0;
        if (nullfb) {
                if (ap->userdata && xfs_inode_is_filestream(ap->ip))
                        args.type = XFS_ALLOCTYPE_NEAR_BNO;
                else
                        args.type = XFS_ALLOCTYPE_START_BNO;
                args.total = ap->total;

                /*
                 * Search for an allocation group with a single extent
                 * large enough for the request.
                 *
                 * If one isn't found, then adjust the minimum allocation
                 * size to the largest space found.
                 */
                startag = ag = XFS_FSB_TO_AGNO(mp, args.fsbno);
                if (startag == NULLAGNUMBER)
                        startag = ag = 0;
                notinit = 0;
                down_read(&mp->m_peraglock);
                while (blen < ap->alen) {
                        pag = &mp->m_perag[ag];
                        if (!pag->pagf_init &&
                            (error = xfs_alloc_pagf_init(mp, args.tp,
                                    ag, XFS_ALLOC_FLAG_TRYLOCK))) {
                                up_read(&mp->m_peraglock);
                                return error;
                        }
                        /*
                         * See xfs_alloc_fix_freelist...
                         */
                        if (pag->pagf_init) {
                                need = XFS_MIN_FREELIST_PAG(pag, mp);
                                delta = need > pag->pagf_flcount ?
                                        need - pag->pagf_flcount : 0;
                                longest = (pag->pagf_longest > delta) ?
                                        (pag->pagf_longest - delta) :
                                        (pag->pagf_flcount > 0 ||
                                         pag->pagf_longest > 0);
                                if (blen < longest)
                                        blen = longest;
                        } else
                                notinit = 1;

                        if (xfs_inode_is_filestream(ap->ip)) {
                                if (blen >= ap->alen)
                                        break;

                                if (ap->userdata) {
                                        /*
                                         * If startag is an invalid AG, we've
                                         * come here once before and
                                         * xfs_filestream_new_ag picked the
                                         * best currently available.
                                         *
                                         * Don't continue looping, since we
                                         * could loop forever.
                                         */
                                        if (startag == NULLAGNUMBER)
                                                break;

                                        error = xfs_filestream_new_ag(ap, &ag);
                                        if (error) {
                                                up_read(&mp->m_peraglock);
                                                return error;
                                        }

                                        /* loop again to set 'blen'*/
                                        startag = NULLAGNUMBER;
                                        continue;
                                }
                        }
                        if (++ag == mp->m_sb.sb_agcount)
                                ag = 0;
                        if (ag == startag)
                                break;
                }
                up_read(&mp->m_peraglock);
                /*
                 * Since the above loop did a BUF_TRYLOCK, it is
                 * possible that there is space for this request.
                 */
                if (notinit || blen < ap->minlen)
                        args.minlen = ap->minlen;
                /*
                 * If the best seen length is less than the request
                 * length, use the best as the minimum.
                 */
                else if (blen < ap->alen)
                        args.minlen = blen;
                /*
                 * Otherwise we've seen an extent as big as alen,
                 * use that as the minimum.
                 */
                else
                        args.minlen = ap->alen;

                /*
                 * set the failure fallback case to look in the selected
                 * AG as the stream may have moved.
                 */
                if (xfs_inode_is_filestream(ap->ip))
                        ap->rval = args.fsbno = XFS_AGB_TO_FSB(mp, ag, 0);
        } else if (ap->low) {
                if (xfs_inode_is_filestream(ap->ip))
                        args.type = XFS_ALLOCTYPE_FIRST_AG;
                else
                        args.type = XFS_ALLOCTYPE_START_BNO;
                args.total = args.minlen = ap->minlen;
        } else {
                args.type = XFS_ALLOCTYPE_NEAR_BNO;
                args.total = ap->total;
                args.minlen = ap->minlen;
        }
        /* apply extent size hints if obtained earlier */
        if (unlikely(align)) {
                args.prod = align;
                if ((args.mod = (xfs_extlen_t)do_mod(ap->off, args.prod)))
                        args.mod = (xfs_extlen_t)(args.prod - args.mod);
        } else if (mp->m_sb.sb_blocksize >= NBPP) {
                args.prod = 1;
                args.mod = 0;
        } else {
                args.prod = NBPP >> mp->m_sb.sb_blocklog;
                if ((args.mod = (xfs_extlen_t)(do_mod(ap->off, args.prod))))
                        args.mod = (xfs_extlen_t)(args.prod - args.mod);
        }
        /*
         * If we are not low on available data blocks, and the
         * underlying logical volume manager is a stripe, and
         * the file offset is zero then try to allocate data
         * blocks on stripe unit boundary.
         * NOTE: ap->aeof is only set if the allocation length
         * is >= the stripe unit and the allocation offset is
         * at the end of file.
         */
        if (!ap->low && ap->aeof) {
                if (!ap->off) {
                        args.alignment = mp->m_dalign;
                        atype = args.type;
                        isaligned = 1;
                        /*
                         * Adjust for alignment
                         */
                        if (blen > args.alignment && blen <= ap->alen)
                                args.minlen = blen - args.alignment;
                        args.minalignslop = 0;
                } else {
                        /*
                         * First try an exact bno allocation.
                         * If it fails then do a near or start bno
                         * allocation with alignment turned on.
                         */
                        atype = args.type;
                        tryagain = 1;
                        args.type = XFS_ALLOCTYPE_THIS_BNO;
                        args.alignment = 1;
                        /*
                         * Compute the minlen+alignment for the
                         * next case.  Set slop so that the value
                         * of minlen+alignment+slop doesn't go up
                         * between the calls.
                         */
                        if (blen > mp->m_dalign && blen <= ap->alen)
                                nextminlen = blen - mp->m_dalign;
                        else
                                nextminlen = args.minlen;
                        if (nextminlen + mp->m_dalign > args.minlen + 1)
                                args.minalignslop =
                                        nextminlen + mp->m_dalign -
                                        args.minlen - 1;
                        else
                                args.minalignslop = 0;
                }
        } else {
                args.alignment = 1;
                args.minalignslop = 0;
        }
        args.minleft = ap->minleft;
        args.wasdel = ap->wasdel;
        args.isfl = 0;
        args.userdata = ap->userdata;
        if ((error = xfs_alloc_vextent(&args)))
                return error;
        if (tryagain && args.fsbno == NULLFSBLOCK) {
                /*
                 * Exact allocation failed. Now try with alignment
                 * turned on.
                 */
                args.type = atype;
                args.fsbno = ap->rval;
                args.alignment = mp->m_dalign;
                args.minlen = nextminlen;
                args.minalignslop = 0;
                isaligned = 1;
                if ((error = xfs_alloc_vextent(&args)))
                        return error;
        }
        if (isaligned && args.fsbno == NULLFSBLOCK) {
                /*
                 * allocation failed, so turn off alignment and
                 * try again.
                 */
                args.type = atype;
                args.fsbno = ap->rval;
                args.alignment = 0;
                if ((error = xfs_alloc_vextent(&args)))
                        return error;
        }
        if (args.fsbno == NULLFSBLOCK && nullfb &&
            args.minlen > ap->minlen) {
                args.minlen = ap->minlen;
                args.type = XFS_ALLOCTYPE_START_BNO;
                args.fsbno = ap->rval;
                if ((error = xfs_alloc_vextent(&args)))
                        return error;
        }
        if (args.fsbno == NULLFSBLOCK && nullfb) {
                args.fsbno = 0;
                args.type = XFS_ALLOCTYPE_FIRST_AG;
                args.total = ap->minlen;
                args.minleft = 0;
                if ((error = xfs_alloc_vextent(&args)))
                        return error;
                ap->low = 1;
        }
        if (args.fsbno != NULLFSBLOCK) {
                ap->firstblock = ap->rval = args.fsbno;
                ASSERT(nullfb || fb_agno == args.agno ||
                       (ap->low && fb_agno < args.agno));
                ap->alen = args.len;
                ap->ip->i_d.di_nblocks += args.len;
                xfs_trans_log_inode(ap->tp, ap->ip, XFS_ILOG_CORE);
                if (ap->wasdel)
                        ap->ip->i_delayed_blks -= args.len;
                /*
                 * Adjust the disk quota also. This was reserved
                 * earlier.
                 */
                XFS_TRANS_MOD_DQUOT_BYINO(mp, ap->tp, ap->ip,
                        ap->wasdel ? XFS_TRANS_DQ_DELBCOUNT :
                                        XFS_TRANS_DQ_BCOUNT,
                        (long) args.len);
        } else {
                ap->rval = NULLFSBLOCK;
                ap->alen = 0;
        }
        return 0;
}

/*
 * xfs_bmap_alloc is called by xfs_bmapi to allocate an extent for a file.
 * It figures out where to ask the underlying allocator to put the new extent.
 */
STATIC int
xfs_bmap_alloc(
        xfs_bmalloca_t  *ap)            /* bmap alloc argument struct */
{
        if ((ap->ip->i_d.di_flags & XFS_DIFLAG_REALTIME) && ap->userdata)
                return xfs_bmap_rtalloc(ap);
        return xfs_bmap_btalloc(ap);
}

/*
 * Transform a btree format file with only one leaf node, where the
 * extents list will fit in the inode, into an extents format file.
 * Since the file extents are already in-core, all we have to do is
 * give up the space for the btree root and pitch the leaf block.
 */
STATIC int                              /* error */
xfs_bmap_btree_to_extents(
        xfs_trans_t             *tp,    /* transaction pointer */
        xfs_inode_t             *ip,    /* incore inode pointer */
        xfs_btree_cur_t         *cur,   /* btree cursor */
        int                     *logflagsp, /* inode logging flags */
        int                     whichfork)  /* data or attr fork */
{
        /* REFERENCED */
        xfs_bmbt_block_t        *cblock;/* child btree block */
        xfs_fsblock_t           cbno;   /* child block number */
        xfs_buf_t               *cbp;   /* child block's buffer */
        int                     error;  /* error return value */
        xfs_ifork_t             *ifp;   /* inode fork data */
        xfs_mount_t             *mp;    /* mount point structure */
        __be64                  *pp;    /* ptr to block address */
        xfs_bmbt_block_t        *rblock;/* root btree block */

        ifp = XFS_IFORK_PTR(ip, whichfork);
        ASSERT(ifp->if_flags & XFS_IFEXTENTS);
        ASSERT(XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_BTREE);
        rblock = ifp->if_broot;
        ASSERT(be16_to_cpu(rblock->bb_level) == 1);
        ASSERT(be16_to_cpu(rblock->bb_numrecs) == 1);
        ASSERT(XFS_BMAP_BROOT_MAXRECS(ifp->if_broot_bytes) == 1);
        mp = ip->i_mount;
        pp = XFS_BMAP_BROOT_PTR_ADDR(rblock, 1, ifp->if_broot_bytes);
        cbno = be64_to_cpu(*pp);
        *logflagsp = 0;
#ifdef DEBUG
        if ((error = xfs_btree_check_lptr(cur, cbno, 1)))
                return error;
#endif
        if ((error = xfs_btree_read_bufl(mp, tp, cbno, 0, &cbp,
                        XFS_BMAP_BTREE_REF)))
                return error;
        cblock = XFS_BUF_TO_BMBT_BLOCK(cbp);
        if ((error = xfs_btree_check_lblock(cur, cblock, 0, cbp)))
                return error;
        xfs_bmap_add_free(cbno, 1, cur->bc_private.b.flist, mp);
        ip->i_d.di_nblocks--;
        XFS_TRANS_MOD_DQUOT_BYINO(mp, tp, ip, XFS_TRANS_DQ_BCOUNT, -1L);
        xfs_trans_binval(tp, cbp);
        if (cur->bc_bufs[0] == cbp)
                cur->bc_bufs[0] = NULL;
        xfs_iroot_realloc(ip, -1, whichfork);
        ASSERT(ifp->if_broot == NULL);
        ASSERT((ifp->if_flags & XFS_IFBROOT) == 0);
        XFS_IFORK_FMT_SET(ip, whichfork, XFS_DINODE_FMT_EXTENTS);
        *logflagsp = XFS_ILOG_CORE | XFS_ILOG_FEXT(whichfork);
        return 0;
}

/*
 * Called by xfs_bmapi to update file extent records and the btree
 * after removing space (or undoing a delayed allocation).
 */
STATIC int                              /* error */
xfs_bmap_del_extent(
        xfs_inode_t             *ip,    /* incore inode pointer */
        xfs_trans_t             *tp,    /* current transaction pointer */
        xfs_extnum_t            idx,    /* extent number to update/delete */
        xfs_bmap_free_t         *flist, /* list of extents to be freed */
        xfs_btree_cur_t         *cur,   /* if null, not a btree */
        xfs_bmbt_irec_t         *del,   /* data to remove from extents */
        int                     *logflagsp, /* inode logging flags */
        xfs_extdelta_t          *delta, /* Change made to incore extents */
        int                     whichfork, /* data or attr fork */
        int                     rsvd)   /* OK to allocate reserved blocks */
{
        xfs_filblks_t           da_new; /* new delay-alloc indirect blocks */
        xfs_filblks_t           da_old; /* old delay-alloc indirect blocks */
        xfs_fsblock_t           del_endblock=0; /* first block past del */
        xfs_fileoff_t           del_endoff;     /* first offset past del */
        int                     delay;  /* current block is delayed allocated */
        int                     do_fx;  /* free extent at end of routine */
        xfs_bmbt_rec_host_t     *ep;    /* current extent entry pointer */
        int                     error;  /* error return value */
        int                     flags;  /* inode logging flags */
        xfs_bmbt_irec_t         got;    /* current extent entry */
        xfs_fileoff_t           got_endoff;     /* first offset past got */
        int                     i;      /* temp state */
        xfs_ifork_t             *ifp;   /* inode fork pointer */
        xfs_mount_t             *mp;    /* mount structure */
        xfs_filblks_t           nblks;  /* quota/sb block count */
        xfs_bmbt_irec_t         new;    /* new record to be inserted */
        /* REFERENCED */
        uint                    qfield; /* quota field to update */
        xfs_filblks_t           temp;   /* for indirect length calculations */
        xfs_filblks_t           temp2;  /* for indirect length calculations */

        XFS_STATS_INC(xs_del_exlist);
        mp = ip->i_mount;
        ifp = XFS_IFORK_PTR(ip, whichfork);
        ASSERT((idx >= 0) && (idx < ifp->if_bytes /
                (uint)sizeof(xfs_bmbt_rec_t)));
        ASSERT(del->br_blockcount > 0);
        ep = xfs_iext_get_ext(ifp, idx);
        xfs_bmbt_get_all(ep, &got);
        ASSERT(got.br_startoff <= del->br_startoff);
        del_endoff = del->br_startoff + del->br_blockcount;
        got_endoff = got.br_startoff + got.br_blockcount;
        ASSERT(got_endoff >= del_endoff);
        delay = ISNULLSTARTBLOCK(got.br_startblock);
        ASSERT(ISNULLSTARTBLOCK(del->br_startblock) == delay);
        flags = 0;
        qfield = 0;
        error = 0;
        /*
         * If deleting a real allocation, must free up the disk space.
         */
        if (!delay) {
                flags = XFS_ILOG_CORE;
                /*
                 * Realtime allocation.  Free it and record di_nblocks update.
                 */
                if (whichfork == XFS_DATA_FORK &&
                    (ip->i_d.di_flags & XFS_DIFLAG_REALTIME)) {
                        xfs_fsblock_t   bno;
                        xfs_filblks_t   len;

                        ASSERT(do_mod(del->br_blockcount,
                                      mp->m_sb.sb_rextsize) == 0);
                        ASSERT(do_mod(del->br_startblock,
                                      mp->m_sb.sb_rextsize) == 0);
                        bno = del->br_startblock;
                        len = del->br_blockcount;
                        do_div(bno, mp->m_sb.sb_rextsize);
                        do_div(len, mp->m_sb.sb_rextsize);
                        if ((error = xfs_rtfree_extent(ip->i_transp, bno,
                                        (xfs_extlen_t)len)))
                                goto done;
                        do_fx = 0;
                        nblks = len * mp->m_sb.sb_rextsize;
                        qfield = XFS_TRANS_DQ_RTBCOUNT;
                }
                /*
                 * Ordinary allocation.
                 */
                else {
                        do_fx = 1;
                        nblks = del->br_blockcount;
                        qfield = XFS_TRANS_DQ_BCOUNT;
                }
                /*
                 * Set up del_endblock and cur for later.
                 */
                del_endblock = del->br_startblock + del->br_blockcount;
                if (cur) {
                        if ((error = xfs_bmbt_lookup_eq(cur, got.br_startoff,
                                        got.br_startblock, got.br_blockcount,
                                        &i)))
                                goto done;
                        ASSERT(i == 1);
                }
                da_old = da_new = 0;
        } else {
                da_old = STARTBLOCKVAL(got.br_startblock);
                da_new = 0;
                nblks = 0;
                do_fx = 0;
        }
        /*
         * Set flag value to use in switch statement.
         * Left-contig is 2, right-contig is 1.
         */
        switch (((got.br_startoff == del->br_startoff) << 1) |
                (got_endoff == del_endoff)) {
        case 3:
                /*
                 * Matches the whole extent.  Delete the entry.
                 */
                XFS_BMAP_TRACE_DELETE("3", ip, idx, 1, whichfork);
                xfs_iext_remove(ifp, idx, 1);
                ifp->if_lastex = idx;
                if (delay)
                        break;
                XFS_IFORK_NEXT_SET(ip, whichfork,
                        XFS_IFORK_NEXTENTS(ip, whichfork) - 1);
                flags |= XFS_ILOG_CORE;
                if (!cur) {
                        flags |= XFS_ILOG_FEXT(whichfork);
                        break;
                }
                if ((error = xfs_bmbt_delete(cur, &i)))
                        goto done;
                ASSERT(i == 1);
                break;

        case 2:
                /*
                 * Deleting the first part of the extent.
                 */
                XFS_BMAP_TRACE_PRE_UPDATE("2", ip, idx, whichfork);
                xfs_bmbt_set_startoff(ep, del_endoff);
                temp = got.br_blockcount - del->br_blockcount;
                xfs_bmbt_set_blockcount(ep, temp);
                ifp->if_lastex = idx;
                if (delay) {
                        temp = XFS_FILBLKS_MIN(xfs_bmap_worst_indlen(ip, temp),
                                da_old);
                        xfs_bmbt_set_startblock(ep, NULLSTARTBLOCK((int)temp));
                        XFS_BMAP_TRACE_POST_UPDATE("2", ip, idx,
                                whichfork);
                        da_new = temp;
                        break;
                }
                xfs_bmbt_set_startblock(ep, del_endblock);
                XFS_BMAP_TRACE_POST_UPDATE("2", ip, idx, whichfork);
                if (!cur) {
                        flags |= XFS_ILOG_FEXT(whichfork);
                        break;
                }
                if ((error = xfs_bmbt_update(cur, del_endoff, del_endblock,
                                got.br_blockcount - del->br_blockcount,
                                got.br_state)))
                        goto done;
                break;

        case 1:
                /*
                 * Deleting the last part of the extent.
                 */
                temp = got.br_blockcount - del->br_blockcount;
                XFS_BMAP_TRACE_PRE_UPDATE("1", ip, idx, whichfork);
                xfs_bmbt_set_blockcount(ep, temp);
                ifp->if_lastex = idx;
                if (delay) {
                        temp = XFS_FILBLKS_MIN(xfs_bmap_worst_indlen(ip, temp),
                                da_old);
                        xfs_bmbt_set_startblock(ep, NULLSTARTBLOCK((int)temp));
                        XFS_BMAP_TRACE_POST_UPDATE("1", ip, idx,
                                whichfork);
                        da_new = temp;
                        break;
                }
                XFS_BMAP_TRACE_POST_UPDATE("1", ip, idx, whichfork);
                if (!cur) {
                        flags |= XFS_ILOG_FEXT(whichfork);
                        break;
                }
                if ((error = xfs_bmbt_update(cur, got.br_startoff,
                                got.br_startblock,
                                got.br_blockcount - del->br_blockcount,
                                got.br_state)))
                        goto done;
                break;

        case 0:
                /*
                 * Deleting the middle of the extent.
                 */
                temp = del->br_startoff - got.br_startoff;
                XFS_BMAP_TRACE_PRE_UPDATE("0", ip, idx, whichfork);
                xfs_bmbt_set_blockcount(ep, temp);
                new.br_startoff = del_endoff;
                temp2 = got_endoff - del_endoff;
                new.br_blockcount = temp2;
                new.br_state = got.br_state;
                if (!delay) {
                        new.br_startblock = del_endblock;
                        flags |= XFS_ILOG_CORE;
                        if (cur) {
                                if ((error = xfs_bmbt_update(cur,
                                                got.br_startoff,
                                                got.br_startblock, temp,
                                                got.br_state)))
                                        goto done;
                                if ((error = xfs_bmbt_increment(cur, 0, &i)))
                                        goto done;
                                cur->bc_rec.b = new;
                                error = xfs_bmbt_insert(cur, &i);
                                if (error && error != ENOSPC)
                                        goto done;
                                /*
                                 * If get no-space back from btree insert,
                                 * it tried a split, and we have a zero
                                 * block reservation.
                                 * Fix up our state and return the error.
                                 */
                                if (error == ENOSPC) {
                                        /*
                                         * Reset the cursor, don't trust
                                         * it after any insert operation.
                                         */
                                        if ((error = xfs_bmbt_lookup_eq(cur,
                                                        got.br_startoff,
                                                        got.br_startblock,
                                                        temp, &i)))
                                                goto done;
                                        ASSERT(i == 1);
                                        /*
                                         * Update the btree record back
                                         * to the original value.
                                         */
                                        if ((error = xfs_bmbt_update(cur,
                                                        got.br_startoff,
                                                        got.br_startblock,
                                                        got.br_blockcount,
                                                        got.br_state)))
                                                goto done;
                                        /*
                                         * Reset the extent record back
                                         * to the original value.
                                         */
                                        xfs_bmbt_set_blockcount(ep,
                                                got.br_blockcount);
                                        flags = 0;
                                        error = XFS_ERROR(ENOSPC);
                                        goto done;
                                }
                                ASSERT(i == 1);
                        } else
                                flags |= XFS_ILOG_FEXT(whichfork);
                        XFS_IFORK_NEXT_SET(ip, whichfork,
                                XFS_IFORK_NEXTENTS(ip, whichfork) + 1);
                } else {
                        ASSERT(whichfork == XFS_DATA_FORK);
                        temp = xfs_bmap_worst_indlen(ip, temp);
                        xfs_bmbt_set_startblock(ep, NULLSTARTBLOCK((int)temp));
                        temp2 = xfs_bmap_worst_indlen(ip, temp2);
                        new.br_startblock = NULLSTARTBLOCK((int)temp2);
                        da_new = temp + temp2;
                        while (da_new > da_old) {
                                if (temp) {
                                        temp--;
                                        da_new--;
                                        xfs_bmbt_set_startblock(ep,
                                                NULLSTARTBLOCK((int)temp));
                                }
                                if (da_new == da_old)
                                        break;
                                if (temp2) {
                                        temp2--;
                                        da_new--;
                                        new.br_startblock =
                                                NULLSTARTBLOCK((int)temp2);
                                }
                        }
                }
                XFS_BMAP_TRACE_POST_UPDATE("0", ip, idx, whichfork);
                XFS_BMAP_TRACE_INSERT("0", ip, idx + 1, 1, &new, NULL,
                        whichfork);
                xfs_iext_insert(ifp, idx + 1, 1, &new);
                ifp->if_lastex = idx + 1;
                break;
        }
        /*
         * If we need to, add to list of extents to delete.
         */
        if (do_fx)
                xfs_bmap_add_free(del->br_startblock, del->br_blockcount, flist,
                        mp);
        /*
         * Adjust inode # blocks in the file.
         */
        if (nblks)
                ip->i_d.di_nblocks -= nblks;
        /*
         * Adjust quota data.
         */
        if (qfield)
                XFS_TRANS_MOD_DQUOT_BYINO(mp, tp, ip, qfield, (long)-nblks);

        /*
         * Account for change in delayed indirect blocks.
         * Nothing to do for disk quota accounting here.
         */
        ASSERT(da_old >= da_new);
        if (da_old > da_new)
                xfs_mod_incore_sb(mp, XFS_SBS_FDBLOCKS, (int64_t)(da_old - da_new),
                        rsvd);
        if (delta) {
                /* DELTA: report the original extent. */
                if (delta->xed_startoff > got.br_startoff)
                        delta->xed_startoff = got.br_startoff;
                if (delta->xed_blockcount < got.br_startoff+got.br_blockcount)
                        delta->xed_blockcount = got.br_startoff +
                                                        got.br_blockcount;
        }
done:
        *logflagsp = flags;
        return error;
}

/*
 * Remove the entry "free" from the free item list.  Prev points to the
 * previous entry, unless "free" is the head of the list.
 */
STATIC void
xfs_bmap_del_free(
        xfs_bmap_free_t         *flist, /* free item list header */
        xfs_bmap_free_item_t    *prev,  /* previous item on list, if any */
        xfs_bmap_free_item_t    *free)  /* list item to be freed */
{
        if (prev)
                prev->xbfi_next = free->xbfi_next;
        else
                flist->xbf_first = free->xbfi_next;
        flist->xbf_count--;
        kmem_zone_free(xfs_bmap_free_item_zone, free);
}

/*
 * Convert an extents-format file into a btree-format file.
 * The new file will have a root block (in the inode) and a single child block.
 */
STATIC int                                      /* error */
xfs_bmap_extents_to_btree(
        xfs_trans_t             *tp,            /* transaction pointer */
        xfs_inode_t             *ip,            /* incore inode pointer */
        xfs_fsblock_t           *firstblock,    /* first-block-allocated */
        xfs_bmap_free_t         *flist,         /* blocks freed in xaction */
        xfs_btree_cur_t         **curp,         /* cursor returned to caller */
        int                     wasdel,         /* converting a delayed alloc */
        int                     *logflagsp,     /* inode logging flags */
        int                     whichfork)      /* data or attr fork */
{
        xfs_bmbt_block_t        *ablock;        /* allocated (child) bt block */
        xfs_buf_t               *abp;           /* buffer for ablock */
        xfs_alloc_arg_t         args;           /* allocation arguments */
        xfs_bmbt_rec_t          *arp;           /* child record pointer */
        xfs_bmbt_block_t        *block;         /* btree root block */
        xfs_btree_cur_t         *cur;           /* bmap btree cursor */
        xfs_bmbt_rec_host_t     *ep;            /* extent record pointer */
        int                     error;          /* error return value */
        xfs_extnum_t            i, cnt;         /* extent record index */
        xfs_ifork_t             *ifp;           /* inode fork pointer */
        xfs_bmbt_key_t          *kp;            /* root block key pointer */
        xfs_mount_t             *mp;            /* mount structure */
        xfs_extnum_t            nextents;       /* number of file extents */
        xfs_bmbt_ptr_t          *pp;            /* root block address pointer */

        ifp = XFS_IFORK_PTR(ip, whichfork);
        ASSERT(XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_EXTENTS);
        ASSERT(ifp->if_ext_max ==
               XFS_IFORK_SIZE(ip, whichfork) / (uint)sizeof(xfs_bmbt_rec_t));
        /*
         * Make space in the inode incore.
         */
        xfs_iroot_realloc(ip, 1, whichfork);
        ifp->if_flags |= XFS_IFBROOT;
        /*
         * Fill in the root.
         */
        block = ifp->if_broot;
        block->bb_magic = cpu_to_be32(XFS_BMAP_MAGIC);
        block->bb_level = cpu_to_be16(1);
        block->bb_numrecs = cpu_to_be16(1);
        block->bb_leftsib = cpu_to_be64(NULLDFSBNO);
        block->bb_rightsib = cpu_to_be64(NULLDFSBNO);
        /*
         * Need a cursor.  Can't allocate until bb_level is filled in.
         */
        mp = ip->i_mount;
        cur = xfs_btree_init_cursor(mp, tp, NULL, 0, XFS_BTNUM_BMAP, ip,
                whichfork);
        cur->bc_private.b.firstblock = *firstblock;
        cur->bc_private.b.flist = flist;
        cur->bc_private.b.flags = wasdel ? XFS_BTCUR_BPRV_WASDEL : 0;
        /*
         * Convert to a btree with two levels, one record in root.
         */
        XFS_IFORK_FMT_SET(ip, whichfork, XFS_DINODE_FMT_BTREE);
        args.tp = tp;
        args.mp = mp;
        args.firstblock = *firstblock;
        if (*firstblock == NULLFSBLOCK) {
                args.type = XFS_ALLOCTYPE_START_BNO;
                args.fsbno = XFS_INO_TO_FSB(mp, ip->i_ino);
        } else if (flist->xbf_low) {
                args.type = XFS_ALLOCTYPE_START_BNO;
                args.fsbno = *firstblock;
        } else {
                args.type = XFS_ALLOCTYPE_NEAR_BNO;
                args.fsbno = *firstblock;
        }
        args.minlen = args.maxlen = args.prod = 1;
        args.total = args.minleft = args.alignment = args.mod = args.isfl =
                args.minalignslop = 0;
        args.wasdel = wasdel;
        *logflagsp = 0;
        if ((error = xfs_alloc_vextent(&args))) {
                xfs_iroot_realloc(ip, -1, whichfork);
                xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
                return error;
        }
        /*
         * Allocation can't fail, the space was reserved.
         */
        ASSERT(args.fsbno != NULLFSBLOCK);
        ASSERT(*firstblock == NULLFSBLOCK ||
               args.agno == XFS_FSB_TO_AGNO(mp, *firstblock) ||
               (flist->xbf_low &&
                args.agno > XFS_FSB_TO_AGNO(mp, *firstblock)));
        *firstblock = cur->bc_private.b.firstblock = args.fsbno;
        cur->bc_private.b.allocated++;
        ip->i_d.di_nblocks++;
        XFS_TRANS_MOD_DQUOT_BYINO(mp, tp, ip, XFS_TRANS_DQ_BCOUNT, 1L);
        abp = xfs_btree_get_bufl(mp, tp, args.fsbno, 0);
        /*
         * Fill in the child block.
         */
        ablock = XFS_BUF_TO_BMBT_BLOCK(abp);
        ablock->bb_magic = cpu_to_be32(XFS_BMAP_MAGIC);
        ablock->bb_level = 0;
        ablock->bb_leftsib = cpu_to_be64(NULLDFSBNO);
        ablock->bb_rightsib = cpu_to_be64(NULLDFSBNO);
        arp = XFS_BMAP_REC_IADDR(ablock, 1, cur);
        nextents = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t);
        for (cnt = i = 0; i < nextents; i++) {
                ep = xfs_iext_get_ext(ifp, i);
                if (!ISNULLSTARTBLOCK(xfs_bmbt_get_startblock(ep))) {
                        arp->l0 = cpu_to_be64(ep->l0);
                        arp->l1 = cpu_to_be64(ep->l1);
                        arp++; cnt++;
                }
        }
        ASSERT(cnt == XFS_IFORK_NEXTENTS(ip, whichfork));
        ablock->bb_numrecs = cpu_to_be16(cnt);
        /*
         * Fill in the root key and pointer.
         */
        kp = XFS_BMAP_KEY_IADDR(block, 1, cur);
        arp = XFS_BMAP_REC_IADDR(ablock, 1, cur);
        kp->br_startoff = cpu_to_be64(xfs_bmbt_disk_get_startoff(arp));
        pp = XFS_BMAP_PTR_IADDR(block, 1, cur);
        *pp = cpu_to_be64(args.fsbno);
        /*
         * Do all this logging at the end so that
         * the root is at the right level.
         */
        xfs_bmbt_log_block(cur, abp, XFS_BB_ALL_BITS);
        xfs_bmbt_log_recs(cur, abp, 1, be16_to_cpu(ablock->bb_numrecs));
        ASSERT(*curp == NULL);
        *curp = cur;
        *logflagsp = XFS_ILOG_CORE | XFS_ILOG_FBROOT(whichfork);
        return 0;
}

/*
 * Helper routine to reset inode di_forkoff field when switching
 * attribute fork from local to extent format - we reset it where
 * possible to make space available for inline data fork extents.
 */
STATIC void
xfs_bmap_forkoff_reset(
        xfs_mount_t     *mp,
        xfs_inode_t     *ip,
        int             whichfork)
{
        if (whichfork == XFS_ATTR_FORK &&
            (ip->i_d.di_format != XFS_DINODE_FMT_DEV) &&
            (ip->i_d.di_format != XFS_DINODE_FMT_UUID) &&
            (ip->i_d.di_format != XFS_DINODE_FMT_BTREE) &&
            ((mp->m_attroffset >> 3) > ip->i_d.di_forkoff)) {
                ip->i_d.di_forkoff = mp->m_attroffset >> 3;
                ip->i_df.if_ext_max = XFS_IFORK_DSIZE(ip) /
                                        (uint)sizeof(xfs_bmbt_rec_t);
                ip->i_afp->if_ext_max = XFS_IFORK_ASIZE(ip) /
                                        (uint)sizeof(xfs_bmbt_rec_t);
        }
}

/*
 * Convert a local file to an extents file.
 * This code is out of bounds for data forks of regular files,
 * since the file data needs to get logged so things will stay consistent.
 * (The bmap-level manipulations are ok, though).
 */
STATIC int                              /* error */
xfs_bmap_local_to_extents(
        xfs_trans_t     *tp,            /* transaction pointer */
        xfs_inode_t     *ip,            /* incore inode pointer */
        xfs_fsblock_t   *firstblock,    /* first block allocated in xaction */
        xfs_extlen_t    total,          /* total blocks needed by transaction */
        int             *logflagsp,     /* inode logging flags */
        int             whichfork)      /* data or attr fork */
{
        int             error;          /* error return value */
        int             flags;          /* logging flags returned */
        xfs_ifork_t     *ifp;           /* inode fork pointer */

        /*
         * We don't want to deal with the case of keeping inode data inline yet.
         * So sending the data fork of a regular inode is invalid.
         */
        ASSERT(!((ip->i_d.di_mode & S_IFMT) == S_IFREG &&
                 whichfork == XFS_DATA_FORK));
        ifp = XFS_IFORK_PTR(ip, whichfork);
        ASSERT(XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_LOCAL);
        flags = 0;
        error = 0;
        if (ifp->if_bytes) {
                xfs_alloc_arg_t args;   /* allocation arguments */
                xfs_buf_t       *bp;    /* buffer for extent block */
                xfs_bmbt_rec_host_t *ep;/* extent record pointer */

                args.tp = tp;
                args.mp = ip->i_mount;
                args.firstblock = *firstblock;
                ASSERT((ifp->if_flags &
                        (XFS_IFINLINE|XFS_IFEXTENTS|XFS_IFEXTIREC)) == XFS_IFINLINE);
                /*
                 * Allocate a block.  We know we need only one, since the
                 * file currently fits in an inode.
                 */
                if (*firstblock == NULLFSBLOCK) {
                        args.fsbno = XFS_INO_TO_FSB(args.mp, ip->i_ino);
                        args.type = XFS_ALLOCTYPE_START_BNO;
                } else {
                        args.fsbno = *firstblock;
                        args.type = XFS_ALLOCTYPE_NEAR_BNO;
                }
                args.total = total;
                args.mod = args.minleft = args.alignment = args.wasdel =
                        args.isfl = args.minalignslop = 0;
                args.minlen = args.maxlen = args.prod = 1;
                if ((error = xfs_alloc_vextent(&args)))
                        goto done;
                /*
                 * Can't fail, the space was reserved.
                 */
                ASSERT(args.fsbno != NULLFSBLOCK);
                ASSERT(args.len == 1);
                *firstblock = args.fsbno;
                bp = xfs_btree_get_bufl(args.mp, tp, args.fsbno, 0);
                memcpy((char *)XFS_BUF_PTR(bp), ifp->if_u1.if_data,
                        ifp->if_bytes);
                xfs_trans_log_buf(tp, bp, 0, ifp->if_bytes - 1);
                xfs_bmap_forkoff_reset(args.mp, ip, whichfork);
                xfs_idata_realloc(ip, -ifp->if_bytes, whichfork);
                xfs_iext_add(ifp, 0, 1);
                ep = xfs_iext_get_ext(ifp, 0);
                xfs_bmbt_set_allf(ep, 0, args.fsbno, 1, XFS_EXT_NORM);
                XFS_BMAP_TRACE_POST_UPDATE("new", ip, 0, whichfork);
                XFS_IFORK_NEXT_SET(ip, whichfork, 1);
                ip->i_d.di_nblocks = 1;
                XFS_TRANS_MOD_DQUOT_BYINO(args.mp, tp, ip,
                        XFS_TRANS_DQ_BCOUNT, 1L);
                flags |= XFS_ILOG_FEXT(whichfork);
        } else {
                ASSERT(XFS_IFORK_NEXTENTS(ip, whichfork) == 0);
                xfs_bmap_forkoff_reset(ip->i_mount, ip, whichfork);
        }
        ifp->if_flags &= ~XFS_IFINLINE;
        ifp->if_flags |= XFS_IFEXTENTS;
        XFS_IFORK_FMT_SET(ip, whichfork, XFS_DINODE_FMT_EXTENTS);
        flags |= XFS_ILOG_CORE;
done:
        *logflagsp = flags;
        return error;
}

/*
 * Search the extent records for the entry containing block bno.
 * If bno lies in a hole, point to the next entry.  If bno lies
 * past eof, *eofp will be set, and *prevp will contain the last
 * entry (null if none).  Else, *lastxp will be set to the index
 * of the found entry; *gotp will contain the entry.
 */
xfs_bmbt_rec_host_t *                   /* pointer to found extent entry */
xfs_bmap_search_multi_extents(
        xfs_ifork_t     *ifp,           /* inode fork pointer */
        xfs_fileoff_t   bno,            /* block number searched for */
        int             *eofp,          /* out: end of file found */
        xfs_extnum_t    *lastxp,        /* out: last extent index */
        xfs_bmbt_irec_t *gotp,          /* out: extent entry found */
        xfs_bmbt_irec_t *prevp)         /* out: previous extent entry found */
{
        xfs_bmbt_rec_host_t *ep;                /* extent record pointer */
        xfs_extnum_t    lastx;          /* last extent index */

        /*
         * Initialize the extent entry structure to catch access to
         * uninitialized br_startblock field.
         */
        gotp->br_startoff = 0xffa5a5a5a5a5a5a5LL;
        gotp->br_blockcount = 0xa55a5a5a5a5a5a5aLL;
        gotp->br_state = XFS_EXT_INVALID;
#if XFS_BIG_BLKNOS
        gotp->br_startblock = 0xffffa5a5a5a5a5a5LL;
#else
        gotp->br_startblock = 0xffffa5a5;
#endif
        prevp->br_startoff = NULLFILEOFF;

        ep = xfs_iext_bno_to_ext(ifp, bno, &lastx);
        if (lastx > 0) {
                xfs_bmbt_get_all(xfs_iext_get_ext(ifp, lastx - 1), prevp);
        }
        if (lastx < (ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t))) {
                xfs_bmbt_get_all(ep, gotp);
                *eofp = 0;
        } else {
                if (lastx > 0) {
                        *gotp = *prevp;
                }
                *eofp = 1;
                ep = NULL;
        }
        *lastxp = lastx;
        return ep;
}

/*
 * Search the extents list for the inode, for the extent containing bno.
 * If bno lies in a hole, point to the next entry.  If bno lies past eof,
 * *eofp will be set, and *prevp will contain the last entry (null if none).
 * Else, *lastxp will be set to the index of the found
 * entry; *gotp will contain the entry.
 */
STATIC xfs_bmbt_rec_host_t *                 /* pointer to found extent entry */
xfs_bmap_search_extents(
        xfs_inode_t     *ip,            /* incore inode pointer */
        xfs_fileoff_t   bno,            /* block number searched for */
        int             fork,           /* data or attr fork */
        int             *eofp,          /* out: end of file found */
        xfs_extnum_t    *lastxp,        /* out: last extent index */
        xfs_bmbt_irec_t *gotp,          /* out: extent entry found */
        xfs_bmbt_irec_t *prevp)         /* out: previous extent entry found */
{
        xfs_ifork_t     *ifp;           /* inode fork pointer */
        xfs_bmbt_rec_host_t  *ep;            /* extent record pointer */

        XFS_STATS_INC(xs_look_exlist);
        ifp = XFS_IFORK_PTR(ip, fork);

        ep = xfs_bmap_search_multi_extents(ifp, bno, eofp, lastxp, gotp, prevp);

        if (unlikely(!(gotp->br_startblock) && (*lastxp != NULLEXTNUM) &&
                     !(XFS_IS_REALTIME_INODE(ip) && fork == XFS_DATA_FORK))) {
                xfs_cmn_err(XFS_PTAG_FSBLOCK_ZERO, CE_ALERT, ip->i_mount,
                                "Access to block zero in inode %llu "
                                "start_block: %llx start_off: %llx "
                                "blkcnt: %llx extent-state: %x lastx: %x\n",
                        (unsigned long long)ip->i_ino,
                        (unsigned long long)gotp->br_startblock,
                        (unsigned long long)gotp->br_startoff,
                        (unsigned long long)gotp->br_blockcount,
                        gotp->br_state, *lastxp);
                *lastxp = NULLEXTNUM;
                *eofp = 1;
                return NULL;
        }
        return ep;
}


#ifdef XFS_BMAP_TRACE
ktrace_t        *xfs_bmap_trace_buf;

/*
 * Add a bmap trace buffer entry.  Base routine for the others.
 */
STATIC void
xfs_bmap_trace_addentry(
        int             opcode,         /* operation */
        const char      *fname,         /* function name */
        char            *desc,          /* operation description */
        xfs_inode_t     *ip,            /* incore inode pointer */
        xfs_extnum_t    idx,            /* index of entry(ies) */
        xfs_extnum_t    cnt,            /* count of entries, 1 or 2 */
        xfs_bmbt_rec_host_t *r1,        /* first record */
        xfs_bmbt_rec_host_t *r2,        /* second record or null */
        int             whichfork)      /* data or attr fork */
{
        xfs_bmbt_rec_host_t tr2;

        ASSERT(cnt == 1 || cnt == 2);
        ASSERT(r1 != NULL);
        if (cnt == 1) {
                ASSERT(r2 == NULL);
                r2 = &tr2;
                memset(&tr2, 0, sizeof(tr2));
        } else
                ASSERT(r2 != NULL);
        ktrace_enter(xfs_bmap_trace_buf,
                (void *)(__psint_t)(opcode | (whichfork << 16)),
                (void *)fname, (void *)desc, (void *)ip,
                (void *)(__psint_t)idx,
                (void *)(__psint_t)cnt,
                (void *)(__psunsigned_t)(ip->i_ino >> 32),
                (void *)(__psunsigned_t)(unsigned)ip->i_ino,
                (void *)(__psunsigned_t)(r1->l0 >> 32),
                (void *)(__psunsigned_t)(unsigned)(r1->l0),
                (void *)(__psunsigned_t)(r1->l1 >> 32),
                (void *)(__psunsigned_t)(unsigned)(r1->l1),
                (void *)(__psunsigned_t)(r2->l0 >> 32),
                (void *)(__psunsigned_t)(unsigned)(r2->l0),
                (void *)(__psunsigned_t)(r2->l1 >> 32),
                (void *)(__psunsigned_t)(unsigned)(r2->l1)
                );
        ASSERT(ip->i_xtrace);
        ktrace_enter(ip->i_xtrace,
                (void *)(__psint_t)(opcode | (whichfork << 16)),
                (void *)fname, (void *)desc, (void *)ip,
                (void *)(__psint_t)idx,
                (void *)(__psint_t)cnt,
                (void *)(__psunsigned_t)(ip->i_ino >> 32),
                (void *)(__psunsigned_t)(unsigned)ip->i_ino,
                (void *)(__psunsigned_t)(r1->l0 >> 32),
                (void *)(__psunsigned_t)(unsigned)(r1->l0),
                (void *)(__psunsigned_t)(r1->l1 >> 32),
                (void *)(__psunsigned_t)(unsigned)(r1->l1),
                (void *)(__psunsigned_t)(r2->l0 >> 32),
                (void *)(__psunsigned_t)(unsigned)(r2->l0),
                (void *)(__psunsigned_t)(r2->l1 >> 32),
                (void *)(__psunsigned_t)(unsigned)(r2->l1)
                );
}

/*
 * Add bmap trace entry prior to a call to xfs_iext_remove.
 */
STATIC void
xfs_bmap_trace_delete(
        const char      *fname,         /* function name */
        char            *desc,          /* operation description */
        xfs_inode_t     *ip,            /* incore inode pointer */
        xfs_extnum_t    idx,            /* index of entry(entries) deleted */
        xfs_extnum_t    cnt,            /* count of entries deleted, 1 or 2 */
        int             whichfork)      /* data or attr fork */
{
        xfs_ifork_t     *ifp;           /* inode fork pointer */

        ifp = XFS_IFORK_PTR(ip, whichfork);
        xfs_bmap_trace_addentry(XFS_BMAP_KTRACE_DELETE, fname, desc, ip, idx,
                cnt, xfs_iext_get_ext(ifp, idx),
                cnt == 2 ? xfs_iext_get_ext(ifp, idx + 1) : NULL,
                whichfork);
}

/*
 * Add bmap trace entry prior to a call to xfs_iext_insert, or
 * reading in the extents list from the disk (in the btree).
 */
STATIC void
xfs_bmap_trace_insert(
        const char      *fname,         /* function name */
        char            *desc,          /* operation description */
        xfs_inode_t     *ip,            /* incore inode pointer */
        xfs_extnum_t    idx,            /* index of entry(entries) inserted */
        xfs_extnum_t    cnt,            /* count of entries inserted, 1 or 2 */
        xfs_bmbt_irec_t *r1,            /* inserted record 1 */
        xfs_bmbt_irec_t *r2,            /* inserted record 2 or null */
        int             whichfork)      /* data or attr fork */
{
        xfs_bmbt_rec_host_t tr1;        /* compressed record 1 */
        xfs_bmbt_rec_host_t tr2;        /* compressed record 2 if needed */

        xfs_bmbt_set_all(&tr1, r1);
        if (cnt == 2) {
                ASSERT(r2 != NULL);
                xfs_bmbt_set_all(&tr2, r2);
        } else {
                ASSERT(cnt == 1);
                ASSERT(r2 == NULL);
        }
        xfs_bmap_trace_addentry(XFS_BMAP_KTRACE_INSERT, fname, desc, ip, idx,
                cnt, &tr1, cnt == 2 ? &tr2 : NULL, whichfork);
}

/*
 * Add bmap trace entry after updating an extent record in place.
 */
STATIC void
xfs_bmap_trace_post_update(
        const char      *fname,         /* function name */
        char            *desc,          /* operation description */
        xfs_inode_t     *ip,            /* incore inode pointer */
        xfs_extnum_t    idx,            /* index of entry updated */
        int             whichfork)      /* data or attr fork */
{
        xfs_ifork_t     *ifp;           /* inode fork pointer */

        ifp = XFS_IFORK_PTR(ip, whichfork);
        xfs_bmap_trace_addentry(XFS_BMAP_KTRACE_POST_UP, fname, desc, ip, idx,
                1, xfs_iext_get_ext(ifp, idx), NULL, whichfork);
}

/*
 * Add bmap trace entry prior to updating an extent record in place.
 */
STATIC void
xfs_bmap_trace_pre_update(
        const char      *fname,         /* function name */
        char            *desc,          /* operation description */
        xfs_inode_t     *ip,            /* incore inode pointer */
        xfs_extnum_t    idx,            /* index of entry to be updated */
        int             whichfork)      /* data or attr fork */
{
        xfs_ifork_t     *ifp;           /* inode fork pointer */

        ifp = XFS_IFORK_PTR(ip, whichfork);
        xfs_bmap_trace_addentry(XFS_BMAP_KTRACE_PRE_UP, fname, desc, ip, idx, 1,
                xfs_iext_get_ext(ifp, idx), NULL, whichfork);
}
#endif  /* XFS_BMAP_TRACE */

/*
 * Compute the worst-case number of indirect blocks that will be used
 * for ip's delayed extent of length "len".
 */
STATIC xfs_filblks_t
xfs_bmap_worst_indlen(
        xfs_inode_t     *ip,            /* incore inode pointer */
        xfs_filblks_t   len)            /* delayed extent length */
{
        int             level;          /* btree level number */
        int             maxrecs;        /* maximum record count at this level */
        xfs_mount_t     *mp;            /* mount structure */
        xfs_filblks_t   rval;           /* return value */

        mp = ip->i_mount;
        maxrecs = mp->m_bmap_dmxr[0];
        for (level = 0, rval = 0;
             level < XFS_BM_MAXLEVELS(mp, XFS_DATA_FORK);
             level++) {
                len += maxrecs - 1;
                do_div(len, maxrecs);
                rval += len;
                if (len == 1)
                        return rval + XFS_BM_MAXLEVELS(mp, XFS_DATA_FORK) -
                                level - 1;
                if (level == 0)
                        maxrecs = mp->m_bmap_dmxr[1];
        }
        return rval;
}

#if defined(XFS_RW_TRACE)
STATIC void
xfs_bunmap_trace(
        xfs_inode_t             *ip,
        xfs_fileoff_t           bno,
        xfs_filblks_t           len,
        int                     flags,
        inst_t                  *ra)
{
        if (ip->i_rwtrace == NULL)
                return;
        ktrace_enter(ip->i_rwtrace,
                (void *)(__psint_t)XFS_BUNMAP,
                (void *)ip,
                (void *)(__psint_t)((ip->i_d.di_size >> 32) & 0xffffffff),
                (void *)(__psint_t)(ip->i_d.di_size & 0xffffffff),
                (void *)(__psint_t)(((xfs_dfiloff_t)bno >> 32) & 0xffffffff),
                (void *)(__psint_t)((xfs_dfiloff_t)bno & 0xffffffff),
                (void *)(__psint_t)len,
                (void *)(__psint_t)flags,
                (void *)(unsigned long)current_cpu(),
                (void *)ra,
                (void *)0,
                (void *)0,
                (void *)0,
                (void *)0,
                (void *)0,
                (void *)0);
}
#endif

/*
 * Convert inode from non-attributed to attributed.
 * Must not be in a transaction, ip must not be locked.
 */
int                                             /* error code */
xfs_bmap_add_attrfork(
        xfs_inode_t             *ip,            /* incore inode pointer */
        int                     size,           /* space new attribute needs */
        int                     rsvd)           /* xact may use reserved blks */
{
        xfs_fsblock_t           firstblock;     /* 1st block/ag allocated */
        xfs_bmap_free_t         flist;          /* freed extent records */
        xfs_mount_t             *mp;            /* mount structure */
        xfs_trans_t             *tp;            /* transaction pointer */
        int                     blks;           /* space reservation */
        int                     version = 1;    /* superblock attr version */
        int                     committed;      /* xaction was committed */
        int                     logflags;       /* logging flags */
        int                     error;          /* error return value */

        ASSERT(XFS_IFORK_Q(ip) == 0);
        ASSERT(ip->i_df.if_ext_max ==
               XFS_IFORK_DSIZE(ip) / (uint)sizeof(xfs_bmbt_rec_t));

        mp = ip->i_mount;
        ASSERT(!XFS_NOT_DQATTACHED(mp, ip));
        tp = xfs_trans_alloc(mp, XFS_TRANS_ADDAFORK);
        blks = XFS_ADDAFORK_SPACE_RES(mp);
        if (rsvd)
                tp->t_flags |= XFS_TRANS_RESERVE;
        if ((error = xfs_trans_reserve(tp, blks, XFS_ADDAFORK_LOG_RES(mp), 0,
                        XFS_TRANS_PERM_LOG_RES, XFS_ADDAFORK_LOG_COUNT)))
                goto error0;
        xfs_ilock(ip, XFS_ILOCK_EXCL);
        error = XFS_TRANS_RESERVE_QUOTA_NBLKS(mp, tp, ip, blks, 0, rsvd ?
                        XFS_QMOPT_RES_REGBLKS | XFS_QMOPT_FORCE_RES :
                        XFS_QMOPT_RES_REGBLKS);
        if (error) {
                xfs_iunlock(ip, XFS_ILOCK_EXCL);
                xfs_trans_cancel(tp, XFS_TRANS_RELEASE_LOG_RES);
                return error;
        }
        if (XFS_IFORK_Q(ip))
                goto error1;
        if (ip->i_d.di_aformat != XFS_DINODE_FMT_EXTENTS) {
                /*
                 * For inodes coming from pre-6.2 filesystems.
                 */
                ASSERT(ip->i_d.di_aformat == 0);
                ip->i_d.di_aformat = XFS_DINODE_FMT_EXTENTS;
        }
        ASSERT(ip->i_d.di_anextents == 0);
        VN_HOLD(XFS_ITOV(ip));
        xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
        xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
        switch (ip->i_d.di_format) {
        case XFS_DINODE_FMT_DEV:
                ip->i_d.di_forkoff = roundup(sizeof(xfs_dev_t), 8) >> 3;
                break;
        case XFS_DINODE_FMT_UUID:
                ip->i_d.di_forkoff = roundup(sizeof(uuid_t), 8) >> 3;
                break;
        case XFS_DINODE_FMT_LOCAL:
        case XFS_DINODE_FMT_EXTENTS:
        case XFS_DINODE_FMT_BTREE:
                ip->i_d.di_forkoff = xfs_attr_shortform_bytesfit(ip, size);
                if (!ip->i_d.di_forkoff)
                        ip->i_d.di_forkoff = mp->m_attroffset >> 3;
                else if (mp->m_flags & XFS_MOUNT_ATTR2)
                        version = 2;
                break;
        default:
                ASSERT(0);
                error = XFS_ERROR(EINVAL);
                goto error1;
        }
        ip->i_df.if_ext_max =
                XFS_IFORK_DSIZE(ip) / (uint)sizeof(xfs_bmbt_rec_t);
        ASSERT(ip->i_afp == NULL);
        ip->i_afp = kmem_zone_zalloc(xfs_ifork_zone, KM_SLEEP);
        ip->i_afp->if_ext_max =
                XFS_IFORK_ASIZE(ip) / (uint)sizeof(xfs_bmbt_rec_t);
        ip->i_afp->if_flags = XFS_IFEXTENTS;
        logflags = 0;
        XFS_BMAP_INIT(&flist, &firstblock);
        switch (ip->i_d.di_format) {
        case XFS_DINODE_FMT_LOCAL:
                error = xfs_bmap_add_attrfork_local(tp, ip, &firstblock, &flist,
                        &logflags);
                break;
        case XFS_DINODE_FMT_EXTENTS:
                error = xfs_bmap_add_attrfork_extents(tp, ip, &firstblock,
                        &flist, &logflags);
                break;
        case XFS_DINODE_FMT_BTREE:
                error = xfs_bmap_add_attrfork_btree(tp, ip, &firstblock, &flist,
                        &logflags);
                break;
        default:
                error = 0;
                break;
        }
        if (logflags)
                xfs_trans_log_inode(tp, ip, logflags);
        if (error)
                goto error2;
        if (!XFS_SB_VERSION_HASATTR(&mp->m_sb) ||
           (!XFS_SB_VERSION_HASATTR2(&mp->m_sb) && version == 2)) {
                __int64_t sbfields = 0;

                spin_lock(&mp->m_sb_lock);
                if (!XFS_SB_VERSION_HASATTR(&mp->m_sb)) {
                        XFS_SB_VERSION_ADDATTR(&mp->m_sb);
                        sbfields |= XFS_SB_VERSIONNUM;
                }
                if (!XFS_SB_VERSION_HASATTR2(&mp->m_sb) && version == 2) {
                        XFS_SB_VERSION_ADDATTR2(&mp->m_sb);
                        sbfields |= (XFS_SB_VERSIONNUM | XFS_SB_FEATURES2);
                }
                if (sbfields) {
                        spin_unlock(&mp->m_sb_lock);
                        xfs_mod_sb(tp, sbfields);
                } else
                        spin_unlock(&mp->m_sb_lock);
        }
        if ((error = xfs_bmap_finish(&tp, &flist, &committed)))
                goto error2;
        error = xfs_trans_commit(tp, XFS_TRANS_PERM_LOG_RES);
        ASSERT(ip->i_df.if_ext_max ==
               XFS_IFORK_DSIZE(ip) / (uint)sizeof(xfs_bmbt_rec_t));
        return error;
error2:
        xfs_bmap_cancel(&flist);
error1:
        ASSERT(ismrlocked(&ip->i_lock,MR_UPDATE));
        xfs_iunlock(ip, XFS_ILOCK_EXCL);
error0:
        xfs_trans_cancel(tp, XFS_TRANS_RELEASE_LOG_RES|XFS_TRANS_ABORT);
        ASSERT(ip->i_df.if_ext_max ==
               XFS_IFORK_DSIZE(ip) / (uint)sizeof(xfs_bmbt_rec_t));
        return error;
}

/*
 * Add the extent to the list of extents to be free at transaction end.
 * The list is maintained sorted (by block number).
 */
/* ARGSUSED */
void
xfs_bmap_add_free(
        xfs_fsblock_t           bno,            /* fs block number of extent */
        xfs_filblks_t           len,            /* length of extent */
        xfs_bmap_free_t         *flist,         /* list of extents */
        xfs_mount_t             *mp)            /* mount point structure */
{
        xfs_bmap_free_item_t    *cur;           /* current (next) element */
        xfs_bmap_free_item_t    *new;           /* new element */
        xfs_bmap_free_item_t    *prev;          /* previous element */
#ifdef DEBUG
        xfs_agnumber_t          agno;
        xfs_agblock_t           agbno;

        ASSERT(bno != NULLFSBLOCK);
        ASSERT(len > 0);
        ASSERT(len <= MAXEXTLEN);
        ASSERT(!ISNULLSTARTBLOCK(bno));
        agno = XFS_FSB_TO_AGNO(mp, bno);
        agbno = XFS_FSB_TO_AGBNO(mp, bno);
        ASSERT(agno < mp->m_sb.sb_agcount);
        ASSERT(agbno < mp->m_sb.sb_agblocks);
        ASSERT(len < mp->m_sb.sb_agblocks);
        ASSERT(agbno + len <= mp->m_sb.sb_agblocks);
#endif
        ASSERT(xfs_bmap_free_item_zone != NULL);
        new = kmem_zone_alloc(xfs_bmap_free_item_zone, KM_SLEEP);
        new->xbfi_startblock = bno;
        new->xbfi_blockcount = (xfs_extlen_t)len;
        for (prev = NULL, cur = flist->xbf_first;
             cur != NULL;
             prev = cur, cur = cur->xbfi_next) {
                if (cur->xbfi_startblock >= bno)
                        break;
        }
        if (prev)
                prev->xbfi_next = new;
        else
                flist->xbf_first = new;
        new->xbfi_next = cur;
        flist->xbf_count++;
}

/*
 * Compute and fill in the value of the maximum depth of a bmap btree
 * in this filesystem.  Done once, during mount.
 */
void
xfs_bmap_compute_maxlevels(
        xfs_mount_t     *mp,            /* file system mount structure */
        int             whichfork)      /* data or attr fork */
{
        int             level;          /* btree level */
        uint            maxblocks;      /* max blocks at this level */
        uint            maxleafents;    /* max leaf entries possible */
        int             maxrootrecs;    /* max records in root block */
        int             minleafrecs;    /* min records in leaf block */
        int             minnoderecs;    /* min records in node block */
        int             sz;             /* root block size */

        /*
         * The maximum number of extents in a file, hence the maximum
         * number of leaf entries, is controlled by the type of di_nextents
         * (a signed 32-bit number, xfs_extnum_t), or by di_anextents
         * (a signed 16-bit number, xfs_aextnum_t).
         */
        if (whichfork == XFS_DATA_FORK) {
                maxleafents = MAXEXTNUM;
                sz = (mp->m_flags & XFS_MOUNT_ATTR2) ?
                        XFS_BMDR_SPACE_CALC(MINDBTPTRS) : mp->m_attroffset;
        } else {
                maxleafents = MAXAEXTNUM;
                sz = (mp->m_flags & XFS_MOUNT_ATTR2) ?
                        XFS_BMDR_SPACE_CALC(MINABTPTRS) :
                        mp->m_sb.sb_inodesize - mp->m_attroffset;
        }
        maxrootrecs = (int)XFS_BTREE_BLOCK_MAXRECS(sz, xfs_bmdr, 0);
        minleafrecs = mp->m_bmap_dmnr[0];
        minnoderecs = mp->m_bmap_dmnr[1];
        maxblocks = (maxleafents + minleafrecs - 1) / minleafrecs;
        for (level = 1; maxblocks > 1; level++) {
                if (maxblocks <= maxrootrecs)
                        maxblocks = 1;
                else
                        maxblocks = (maxblocks + minnoderecs - 1) / minnoderecs;
        }
        mp->m_bm_maxlevels[whichfork] = level;
}

/*
 * Routine to be called at transaction's end by xfs_bmapi, xfs_bunmapi
 * caller.  Frees all the extents that need freeing, which must be done
 * last due to locking considerations.  We never free any extents in
 * the first transaction.  This is to allow the caller to make the first
 * transaction a synchronous one so that the pointers to the data being
 * broken in this transaction will be permanent before the data is actually
 * freed.  This is necessary to prevent blocks from being reallocated
 * and written to before the free and reallocation are actually permanent.
 * We do not just make the first transaction synchronous here, because
 * there are more efficient ways to gain the same protection in some cases
 * (see the file truncation code).
 *
 * Return 1 if the given transaction was committed and a new one
 * started, and 0 otherwise in the committed parameter.
 */
/*ARGSUSED*/
int                                             /* error */
xfs_bmap_finish(
        xfs_trans_t             **tp,           /* transaction pointer addr */
        xfs_bmap_free_t         *flist,         /* i/o: list extents to free */
        int                     *committed)     /* xact committed or not */
{
        xfs_efd_log_item_t      *efd;           /* extent free data */
        xfs_efi_log_item_t      *efi;           /* extent free intention */
        int                     error;          /* error return value */
        xfs_bmap_free_item_t    *free;          /* free extent item */
        unsigned int            logres;         /* new log reservation */
        unsigned int            logcount;       /* new log count */
        xfs_mount_t             *mp;            /* filesystem mount structure */
        xfs_bmap_free_item_t    *next;          /* next item on free list */
        xfs_trans_t             *ntp;           /* new transaction pointer */

        ASSERT((*tp)->t_flags & XFS_TRANS_PERM_LOG_RES);
        if (flist->xbf_count == 0) {
                *committed = 0;
                return 0;
        }
        ntp = *tp;
        efi = xfs_trans_get_efi(ntp, flist->xbf_count);
        for (free = flist->xbf_first; free; free = free->xbfi_next)
                xfs_trans_log_efi_extent(ntp, efi, free->xbfi_startblock,
                        free->xbfi_blockcount);
        logres = ntp->t_log_res;
        logcount = ntp->t_log_count;
        ntp = xfs_trans_dup(*tp);
        error = xfs_trans_commit(*tp, 0);
        *tp = ntp;
        *committed = 1;
        /*
         * We have a new transaction, so we should return committed=1,
         * even though we're returning an error.
         */
        if (error) {
                return error;
        }
        if ((error = xfs_trans_reserve(ntp, 0, logres, 0, XFS_TRANS_PERM_LOG_RES,
                        logcount)))
                return error;
        efd = xfs_trans_get_efd(ntp, efi, flist->xbf_count);
        for (free = flist->xbf_first; free != NULL; free = next) {
                next = free->xbfi_next;
                if ((error = xfs_free_extent(ntp, free->xbfi_startblock,
                                free->xbfi_blockcount))) {
                        /*
                         * The bmap free list will be cleaned up at a
                         * higher level.  The EFI will be canceled when
                         * this transaction is aborted.
                         * Need to force shutdown here to make sure it
                         * happens, since this transaction may not be
                         * dirty yet.
                         */
                        mp = ntp->t_mountp;
                        if (!XFS_FORCED_SHUTDOWN(mp))
                                xfs_force_shutdown(mp,
                                                   (error == EFSCORRUPTED) ?
                                                   SHUTDOWN_CORRUPT_INCORE :
                                                   SHUTDOWN_META_IO_ERROR);
                        return error;
                }
                xfs_trans_log_efd_extent(ntp, efd, free->xbfi_startblock,
                        free->xbfi_blockcount);
                xfs_bmap_del_free(flist, NULL, free);
        }
        return 0;
}

/*
 * Free up any items left in the list.
 */
void
xfs_bmap_cancel(
        xfs_bmap_free_t         *flist) /* list of bmap_free_items */
{
        xfs_bmap_free_item_t    *free;  /* free list item */
        xfs_bmap_free_item_t    *next;

        if (flist->xbf_count == 0)
                return;
        ASSERT(flist->xbf_first != NULL);
        for (free = flist->xbf_first; free; free = next) {
                next = free->xbfi_next;
                xfs_bmap_del_free(flist, NULL, free);
        }
        ASSERT(flist->xbf_count == 0);
}

/*
 * Returns the file-relative block number of the first unused block(s)
 * in the file with at least "len" logically contiguous blocks free.
 * This is the lowest-address hole if the file has holes, else the first block
 * past the end of file.
 * Return 0 if the file is currently local (in-inode).
 */
int                                             /* error */
xfs_bmap_first_unused(
        xfs_trans_t     *tp,                    /* transaction pointer */
        xfs_inode_t     *ip,                    /* incore inode */
        xfs_extlen_t    len,                    /* size of hole to find */
        xfs_fileoff_t   *first_unused,          /* unused block */
        int             whichfork)              /* data or attr fork */
{
        int             error;                  /* error return value */
        int             idx;                    /* extent record index */
        xfs_ifork_t     *ifp;                   /* inode fork pointer */
        xfs_fileoff_t   lastaddr;               /* last block number seen */
        xfs_fileoff_t   lowest;                 /* lowest useful block */
        xfs_fileoff_t   max;                    /* starting useful block */
        xfs_fileoff_t   off;                    /* offset for this block */
        xfs_extnum_t    nextents;               /* number of extent entries */

        ASSERT(XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_BTREE ||
               XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_EXTENTS ||
               XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_LOCAL);
        if (XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_LOCAL) {
                *first_unused = 0;
                return 0;
        }
        ifp = XFS_IFORK_PTR(ip, whichfork);
        if (!(ifp->if_flags & XFS_IFEXTENTS) &&
            (error = xfs_iread_extents(tp, ip, whichfork)))
                return error;
        lowest = *first_unused;
        nextents = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t);
        for (idx = 0, lastaddr = 0, max = lowest; idx < nextents; idx++) {
                xfs_bmbt_rec_host_t *ep = xfs_iext_get_ext(ifp, idx);
                off = xfs_bmbt_get_startoff(ep);
                /*
                 * See if the hole before this extent will work.
                 */
                if (off >= lowest + len && off - max >= len) {
                        *first_unused = max;
                        return 0;
                }
                lastaddr = off + xfs_bmbt_get_blockcount(ep);
                max = XFS_FILEOFF_MAX(lastaddr, lowest);
        }
        *first_unused = max;
        return 0;
}

/*
 * Returns the file-relative block number of the last block + 1 before
 * last_block (input value) in the file.
 * This is not based on i_size, it is based on the extent records.
 * Returns 0 for local files, as they do not have extent records.
 */
int                                             /* error */
xfs_bmap_last_before(
        xfs_trans_t     *tp,                    /* transaction pointer */
        xfs_inode_t     *ip,                    /* incore inode */
        xfs_fileoff_t   *last_block,            /* last block */
        int             whichfork)              /* data or attr fork */
{
        xfs_fileoff_t   bno;                    /* input file offset */
        int             eof;                    /* hit end of file */
        xfs_bmbt_rec_host_t *ep;                /* pointer to last extent */
        int             error;                  /* error return value */
        xfs_bmbt_irec_t got;                    /* current extent value */
        xfs_ifork_t     *ifp;                   /* inode fork pointer */
        xfs_extnum_t    lastx;                  /* last extent used */
        xfs_bmbt_irec_t prev;                   /* previous extent value */

        if (XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_BTREE &&
            XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_EXTENTS &&
            XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_LOCAL)
               return XFS_ERROR(EIO);
        if (XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_LOCAL) {
                *last_block = 0;
                return 0;
        }
        ifp = XFS_IFORK_PTR(ip, whichfork);
        if (!(ifp->if_flags & XFS_IFEXTENTS) &&
            (error = xfs_iread_extents(tp, ip, whichfork)))
                return error;
        bno = *last_block - 1;
        ep = xfs_bmap_search_extents(ip, bno, whichfork, &eof, &lastx, &got,
                &prev);
        if (eof || xfs_bmbt_get_startoff(ep) > bno) {
                if (prev.br_startoff == NULLFILEOFF)
                        *last_block = 0;
                else
                        *last_block = prev.br_startoff + prev.br_blockcount;
        }
        /*
         * Otherwise *last_block is already the right answer.
         */
        return 0;
}

/*
 * Returns the file-relative block number of the first block past eof in
 * the file.  This is not based on i_size, it is based on the extent records.
 * Returns 0 for local files, as they do not have extent records.
 */
int                                             /* error */
xfs_bmap_last_offset(
        xfs_trans_t     *tp,                    /* transaction pointer */
        xfs_inode_t     *ip,                    /* incore inode */
        xfs_fileoff_t   *last_block,            /* last block */
        int             whichfork)              /* data or attr fork */
{
        xfs_bmbt_rec_host_t *ep;                /* pointer to last extent */
        int             error;                  /* error return value */
        xfs_ifork_t     *ifp;                   /* inode fork pointer */
        xfs_extnum_t    nextents;               /* number of extent entries */

        if (XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_BTREE &&
            XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_EXTENTS &&
            XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_LOCAL)
               return XFS_ERROR(EIO);
        if (XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_LOCAL) {
                *last_block = 0;
                return 0;
        }
        ifp = XFS_IFORK_PTR(ip, whichfork);
        if (!(ifp->if_flags & XFS_IFEXTENTS) &&
            (error = xfs_iread_extents(tp, ip, whichfork)))
                return error;
        nextents = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t);
        if (!nextents) {
                *last_block = 0;
                return 0;
        }
        ep = xfs_iext_get_ext(ifp, nextents - 1);
        *last_block = xfs_bmbt_get_startoff(ep) + xfs_bmbt_get_blockcount(ep);
        return 0;
}

/*
 * Returns whether the selected fork of the inode has exactly one
 * block or not.  For the data fork we check this matches di_size,
 * implying the file's range is 0..bsize-1.
 */
int                                     /* 1=>1 block, 0=>otherwise */
xfs_bmap_one_block(
        xfs_inode_t     *ip,            /* incore inode */
        int             whichfork)      /* data or attr fork */
{
        xfs_bmbt_rec_host_t *ep;        /* ptr to fork's extent */
        xfs_ifork_t     *ifp;           /* inode fork pointer */
        int             rval;           /* return value */
        xfs_bmbt_irec_t s;              /* internal version of extent */

#ifndef DEBUG
        if (whichfork == XFS_DATA_FORK) {
                return ((ip->i_d.di_mode & S_IFMT) == S_IFREG) ?
                        (ip->i_size == ip->i_mount->m_sb.sb_blocksize) :
                        (ip->i_d.di_size == ip->i_mount->m_sb.sb_blocksize);
        }
#endif  /* !DEBUG */
        if (XFS_IFORK_NEXTENTS(ip, whichfork) != 1)
                return 0;
        if (XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_EXTENTS)
                return 0;
        ifp = XFS_IFORK_PTR(ip, whichfork);
        ASSERT(ifp->if_flags & XFS_IFEXTENTS);
        ep = xfs_iext_get_ext(ifp, 0);
        xfs_bmbt_get_all(ep, &s);
        rval = s.br_startoff == 0 && s.br_blockcount == 1;
        if (rval && whichfork == XFS_DATA_FORK)
                ASSERT(ip->i_size == ip->i_mount->m_sb.sb_blocksize);
        return rval;
}

/*
 * Read in the extents to if_extents.
 * All inode fields are set up by caller, we just traverse the btree
 * and copy the records in. If the file system cannot contain unwritten
 * extents, the records are checked for no "state" flags.
 */
int                                     /* error */
xfs_bmap_read_extents(
        xfs_trans_t             *tp,    /* transaction pointer */
        xfs_inode_t             *ip,    /* incore inode */
        int                     whichfork) /* data or attr fork */
{
        xfs_bmbt_block_t        *block; /* current btree block */
        xfs_fsblock_t           bno;    /* block # of "block" */
        xfs_buf_t               *bp;    /* buffer for "block" */
        int                     error;  /* error return value */
        xfs_exntfmt_t           exntf;  /* XFS_EXTFMT_NOSTATE, if checking */
        xfs_extnum_t            i, j;   /* index into the extents list */
        xfs_ifork_t             *ifp;   /* fork structure */
        int                     level;  /* btree level, for checking */
        xfs_mount_t             *mp;    /* file system mount structure */
        __be64                  *pp;    /* pointer to block address */
        /* REFERENCED */
        xfs_extnum_t            room;   /* number of entries there's room for */

        bno = NULLFSBLOCK;
        mp = ip->i_mount;
        ifp = XFS_IFORK_PTR(ip, whichfork);
        exntf = (whichfork != XFS_DATA_FORK) ? XFS_EXTFMT_NOSTATE :
                                        XFS_EXTFMT_INODE(ip);
        block = ifp->if_broot;
        /*
         * Root level must use BMAP_BROOT_PTR_ADDR macro to get ptr out.
         */
        level = be16_to_cpu(block->bb_level);
        ASSERT(level > 0);
        pp = XFS_BMAP_BROOT_PTR_ADDR(block, 1, ifp->if_broot_bytes);
        bno = be64_to_cpu(*pp);
        ASSERT(bno != NULLDFSBNO);
        ASSERT(XFS_FSB_TO_AGNO(mp, bno) < mp->m_sb.sb_agcount);
        ASSERT(XFS_FSB_TO_AGBNO(mp, bno) < mp->m_sb.sb_agblocks);
        /*
         * Go down the tree until leaf level is reached, following the first
         * pointer (leftmost) at each level.
         */
        while (level-- > 0) {
                if ((error = xfs_btree_read_bufl(mp, tp, bno, 0, &bp,
                                XFS_BMAP_BTREE_REF)))
                        return error;
                block = XFS_BUF_TO_BMBT_BLOCK(bp);
                XFS_WANT_CORRUPTED_GOTO(
                        XFS_BMAP_SANITY_CHECK(mp, block, level),
                        error0);
                if (level == 0)
                        break;
                pp = XFS_BTREE_PTR_ADDR(xfs_bmbt, block, 1, mp->m_bmap_dmxr[1]);
                bno = be64_to_cpu(*pp);
                XFS_WANT_CORRUPTED_GOTO(XFS_FSB_SANITY_CHECK(mp, bno), error0);
                xfs_trans_brelse(tp, bp);
        }
        /*
         * Here with bp and block set to the leftmost leaf node in the tree.
         */
        room = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t);
        i = 0;
        /*
         * Loop over all leaf nodes.  Copy information to the extent records.
         */
        for (;;) {
                xfs_bmbt_rec_t  *frp;
                xfs_fsblock_t   nextbno;
                xfs_extnum_t    num_recs;
                xfs_extnum_t    start;


                num_recs = be16_to_cpu(block->bb_numrecs);
                if (unlikely(i + num_recs > room)) {
                        ASSERT(i + num_recs <= room);
                        xfs_fs_repair_cmn_err(CE_WARN, ip->i_mount,
                                "corrupt dinode %Lu, (btree extents).",
                                (unsigned long long) ip->i_ino);
                        XFS_ERROR_REPORT("xfs_bmap_read_extents(1)",
                                         XFS_ERRLEVEL_LOW,
                                        ip->i_mount);
                        goto error0;
                }
                XFS_WANT_CORRUPTED_GOTO(
                        XFS_BMAP_SANITY_CHECK(mp, block, 0),
                        error0);
                /*
                 * Read-ahead the next leaf block, if any.
                 */
                nextbno = be64_to_cpu(block->bb_rightsib);
                if (nextbno != NULLFSBLOCK)
                        xfs_btree_reada_bufl(mp, nextbno, 1);
                /*
                 * Copy records into the extent records.
                 */
                frp = XFS_BTREE_REC_ADDR(xfs_bmbt, block, 1);
                start = i;
                for (j = 0; j < num_recs; j++, i++, frp++) {
                        xfs_bmbt_rec_host_t *trp = xfs_iext_get_ext(ifp, i);
                        trp->l0 = be64_to_cpu(frp->l0);
                        trp->l1 = be64_to_cpu(frp->l1);
                }
                if (exntf == XFS_EXTFMT_NOSTATE) {
                        /*
                         * Check all attribute bmap btree records and
                         * any "older" data bmap btree records for a
                         * set bit in the "extent flag" position.
                         */
                        if (unlikely(xfs_check_nostate_extents(ifp,
                                        start, num_recs))) {
                                XFS_ERROR_REPORT("xfs_bmap_read_extents(2)",
                                                 XFS_ERRLEVEL_LOW,
                                                 ip->i_mount);
                                goto error0;
                        }
                }
                xfs_trans_brelse(tp, bp);
                bno = nextbno;
                /*
                 * If we've reached the end, stop.
                 */
                if (bno == NULLFSBLOCK)
                        break;
                if ((error = xfs_btree_read_bufl(mp, tp, bno, 0, &bp,
                                XFS_BMAP_BTREE_REF)))
                        return error;
                block = XFS_BUF_TO_BMBT_BLOCK(bp);
        }
        ASSERT(i == (ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t)));
        ASSERT(i == XFS_IFORK_NEXTENTS(ip, whichfork));
        XFS_BMAP_TRACE_EXLIST(ip, i, whichfork);
        return 0;
error0:
        xfs_trans_brelse(tp, bp);
        return XFS_ERROR(EFSCORRUPTED);
}

#ifdef XFS_BMAP_TRACE
/*
 * Add bmap trace insert entries for all the contents of the extent records.
 */
void
xfs_bmap_trace_exlist(
        const char      *fname,         /* function name */
        xfs_inode_t     *ip,            /* incore inode pointer */
        xfs_extnum_t    cnt,            /* count of entries in the list */
        int             whichfork)      /* data or attr fork */
{
        xfs_bmbt_rec_host_t *ep;        /* current extent record */
        xfs_extnum_t    idx;            /* extent record index */
        xfs_ifork_t     *ifp;           /* inode fork pointer */
        xfs_bmbt_irec_t s;              /* file extent record */

        ifp = XFS_IFORK_PTR(ip, whichfork);
        ASSERT(cnt == (ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t)));
        for (idx = 0; idx < cnt; idx++) {
                ep = xfs_iext_get_ext(ifp, idx);
                xfs_bmbt_get_all(ep, &s);
                XFS_BMAP_TRACE_INSERT("exlist", ip, idx, 1, &s, NULL,
                        whichfork);
        }
}
#endif

#ifdef DEBUG
/*
 * Validate that the bmbt_irecs being returned from bmapi are valid
 * given the callers original parameters.  Specifically check the
 * ranges of the returned irecs to ensure that they only extent beyond
 * the given parameters if the XFS_BMAPI_ENTIRE flag was set.
 */
STATIC void
xfs_bmap_validate_ret(
        xfs_fileoff_t           bno,
        xfs_filblks_t           len,
        int                     flags,
        xfs_bmbt_irec_t         *mval,
        int                     nmap,
        int                     ret_nmap)
{
        int                     i;              /* index to map values */

        ASSERT(ret_nmap <= nmap);

        for (i = 0; i < ret_nmap; i++) {
                ASSERT(mval[i].br_blockcount > 0);
                if (!(flags & XFS_BMAPI_ENTIRE)) {
                        ASSERT(mval[i].br_startoff >= bno);
                        ASSERT(mval[i].br_blockcount <= len);
                        ASSERT(mval[i].br_startoff + mval[i].br_blockcount <=
                               bno + len);
                } else {
                        ASSERT(mval[i].br_startoff < bno + len);
                        ASSERT(mval[i].br_startoff + mval[i].br_blockcount >
                               bno);
                }
                ASSERT(i == 0 ||
                       mval[i - 1].br_startoff + mval[i - 1].br_blockcount ==
                       mval[i].br_startoff);
                if ((flags & XFS_BMAPI_WRITE) && !(flags & XFS_BMAPI_DELAY))
                        ASSERT(mval[i].br_startblock != DELAYSTARTBLOCK &&
                               mval[i].br_startblock != HOLESTARTBLOCK);
                ASSERT(mval[i].br_state == XFS_EXT_NORM ||
                       mval[i].br_state == XFS_EXT_UNWRITTEN);
        }
}
#endif /* DEBUG */


/*
 * Map file blocks to filesystem blocks.
 * File range is given by the bno/len pair.
 * Adds blocks to file if a write ("flags & XFS_BMAPI_WRITE" set)
 * into a hole or past eof.
 * Only allocates blocks from a single allocation group,
 * to avoid locking problems.
 * The returned value in "firstblock" from the first call in a transaction
 * must be remembered and presented to subsequent calls in "firstblock".
 * An upper bound for the number of blocks to be allocated is supplied to
 * the first call in "total"; if no allocation group has that many free
 * blocks then the call will fail (return NULLFSBLOCK in "firstblock").
 */
int                                     /* error */
xfs_bmapi(
        xfs_trans_t     *tp,            /* transaction pointer */
        xfs_inode_t     *ip,            /* incore inode */
        xfs_fileoff_t   bno,            /* starting file offs. mapped */
        xfs_filblks_t   len,            /* length to map in file */
        int             flags,          /* XFS_BMAPI_... */
        xfs_fsblock_t   *firstblock,    /* first allocated block
                                           controls a.g. for allocs */
        xfs_extlen_t    total,          /* total blocks needed */
        xfs_bmbt_irec_t *mval,          /* output: map values */
        int             *nmap,          /* i/o: mval size/count */
        xfs_bmap_free_t *flist,         /* i/o: list extents to free */
        xfs_extdelta_t  *delta)         /* o: change made to incore extents */
{
        xfs_fsblock_t   abno;           /* allocated block number */
        xfs_extlen_t    alen;           /* allocated extent length */
        xfs_fileoff_t   aoff;           /* allocated file offset */
        xfs_bmalloca_t  bma;            /* args for xfs_bmap_alloc */
        xfs_btree_cur_t *cur;           /* bmap btree cursor */
        xfs_fileoff_t   end;            /* end of mapped file region */
        int             eof;            /* we've hit the end of extents */
        xfs_bmbt_rec_host_t *ep;        /* extent record pointer */
        int             error;          /* error return */
        xfs_bmbt_irec_t got;            /* current file extent record */
        xfs_ifork_t     *ifp;           /* inode fork pointer */
        xfs_extlen_t    indlen;         /* indirect blocks length */
        xfs_extnum_t    lastx;          /* last useful extent number */
        int             logflags;       /* flags for transaction logging */
        xfs_extlen_t    minleft;        /* min blocks left after allocation */
        xfs_extlen_t    minlen;         /* min allocation size */
        xfs_mount_t     *mp;            /* xfs mount structure */
        int             n;              /* current extent index */
        int             nallocs;        /* number of extents alloc\'d */
        xfs_extnum_t    nextents;       /* number of extents in file */
        xfs_fileoff_t   obno;           /* old block number (offset) */
        xfs_bmbt_irec_t prev;           /* previous file extent record */
        int             tmp_logflags;   /* temp flags holder */
        int             whichfork;      /* data or attr fork */
        char            inhole;         /* current location is hole in file */
        char            wasdelay;       /* old extent was delayed */
        char            wr;             /* this is a write request */
        char            rt;             /* this is a realtime file */
#ifdef DEBUG
        xfs_fileoff_t   orig_bno;       /* original block number value */
        int             orig_flags;     /* original flags arg value */
        xfs_filblks_t   orig_len;       /* original value of len arg */
        xfs_bmbt_irec_t *orig_mval;     /* original value of mval */
        int             orig_nmap;      /* original value of *nmap */

        orig_bno = bno;
        orig_len = len;
        orig_flags = flags;
        orig_mval = mval;
        orig_nmap = *nmap;
#endif
        ASSERT(*nmap >= 1);
        ASSERT(*nmap <= XFS_BMAP_MAX_NMAP || !(flags & XFS_BMAPI_WRITE));
        whichfork = (flags & XFS_BMAPI_ATTRFORK) ?
                XFS_ATTR_FORK : XFS_DATA_FORK;
        mp = ip->i_mount;
        if (unlikely(XFS_TEST_ERROR(
            (XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_EXTENTS &&
             XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_BTREE &&
             XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_LOCAL),
             mp, XFS_ERRTAG_BMAPIFORMAT, XFS_RANDOM_BMAPIFORMAT))) {
                XFS_ERROR_REPORT("xfs_bmapi", XFS_ERRLEVEL_LOW, mp);
                return XFS_ERROR(EFSCORRUPTED);
        }
        if (XFS_FORCED_SHUTDOWN(mp))
                return XFS_ERROR(EIO);
        rt = (whichfork == XFS_DATA_FORK) && XFS_IS_REALTIME_INODE(ip);
        ifp = XFS_IFORK_PTR(ip, whichfork);
        ASSERT(ifp->if_ext_max ==
               XFS_IFORK_SIZE(ip, whichfork) / (uint)sizeof(xfs_bmbt_rec_t));
        if ((wr = (flags & XFS_BMAPI_WRITE)) != 0)
                XFS_STATS_INC(xs_blk_mapw);
        else
                XFS_STATS_INC(xs_blk_mapr);
        /*
         * IGSTATE flag is used to combine extents which
         * differ only due to the state of the extents.
         * This technique is used from xfs_getbmap()
         * when the caller does not wish to see the
         * separation (which is the default).
         *
         * This technique is also used when writing a
         * buffer which has been partially written,
         * (usually by being flushed during a chunkread),
         * to ensure one write takes place. This also
         * prevents a change in the xfs inode extents at
         * this time, intentionally. This change occurs
         * on completion of the write operation, in
         * xfs_strat_comp(), where the xfs_bmapi() call
         * is transactioned, and the extents combined.
         */
        if ((flags & XFS_BMAPI_IGSTATE) && wr)  /* if writing unwritten space */
                wr = 0;                         /* no allocations are allowed */
        ASSERT(wr || !(flags & XFS_BMAPI_DELAY));
        logflags = 0;
        nallocs = 0;
        cur = NULL;
        if (XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_LOCAL) {
                ASSERT(wr && tp);
                if ((error = xfs_bmap_local_to_extents(tp, ip,
                                firstblock, total, &logflags, whichfork)))
                        goto error0;
        }
        if (wr && *firstblock == NULLFSBLOCK) {
                if (XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_BTREE)
                        minleft = be16_to_cpu(ifp->if_broot->bb_level) + 1;
                else
                        minleft = 1;
        } else
                minleft = 0;
        if (!(ifp->if_flags & XFS_IFEXTENTS) &&
            (error = xfs_iread_extents(tp, ip, whichfork)))
                goto error0;
        ep = xfs_bmap_search_extents(ip, bno, whichfork, &eof, &lastx, &got,
                &prev);
        nextents = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t);
        n = 0;
        end = bno + len;
        obno = bno;
        bma.ip = NULL;
        if (delta) {
                delta->xed_startoff = NULLFILEOFF;
                delta->xed_blockcount = 0;
        }
        while (bno < end && n < *nmap) {
                /*
                 * Reading past eof, act as though there's a hole
                 * up to end.
                 */
                if (eof && !wr)
                        got.br_startoff = end;
                inhole = eof || got.br_startoff > bno;
                wasdelay = wr && !inhole && !(flags & XFS_BMAPI_DELAY) &&
                        ISNULLSTARTBLOCK(got.br_startblock);
                /*
                 * First, deal with the hole before the allocated space
                 * that we found, if any.
                 */
                if (wr && (inhole || wasdelay)) {
                        /*
                         * For the wasdelay case, we could also just
                         * allocate the stuff asked for in this bmap call
                         * but that wouldn't be as good.
                         */
                        if (wasdelay && !(flags & XFS_BMAPI_EXACT)) {
                                alen = (xfs_extlen_t)got.br_blockcount;
                                aoff = got.br_startoff;
                                if (lastx != NULLEXTNUM && lastx) {
                                        ep = xfs_iext_get_ext(ifp, lastx - 1);
                                        xfs_bmbt_get_all(ep, &prev);
                                }
                        } else if (wasdelay) {
                                alen = (xfs_extlen_t)
                                        XFS_FILBLKS_MIN(len,
                                                (got.br_startoff +
                                                 got.br_blockcount) - bno);
                                aoff = bno;
                        } else {
                                alen = (xfs_extlen_t)
                                        XFS_FILBLKS_MIN(len, MAXEXTLEN);
                                if (!eof)
                                        alen = (xfs_extlen_t)
                                                XFS_FILBLKS_MIN(alen,
                                                        got.br_startoff - bno);
                                aoff = bno;
                        }
                        minlen = (flags & XFS_BMAPI_CONTIG) ? alen : 1;
                        if (flags & XFS_BMAPI_DELAY) {
                                xfs_extlen_t    extsz;

                                /* Figure out the extent size, adjust alen */
                                extsz = xfs_get_extsz_hint(ip);
                                if (extsz) {
                                        error = xfs_bmap_extsize_align(mp,
                                                        &got, &prev, extsz,
                                                        rt, eof,
                                                        flags&XFS_BMAPI_DELAY,
                                                        flags&XFS_BMAPI_CONVERT,
                                                        &aoff, &alen);
                                        ASSERT(!error);
                                }

                                if (rt)
                                        extsz = alen / mp->m_sb.sb_rextsize;

                                /*
                                 * Make a transaction-less quota reservation for
                                 * delayed allocation blocks. This number gets
                                 * adjusted later.  We return if we haven't
                                 * allocated blocks already inside this loop.
                                 */
                                if ((error = XFS_TRANS_RESERVE_QUOTA_NBLKS(
                                                mp, NULL, ip, (long)alen, 0,
                                                rt ? XFS_QMOPT_RES_RTBLKS :
                                                     XFS_QMOPT_RES_REGBLKS))) {
                                        if (n == 0) {
                                                *nmap = 0;
                                                ASSERT(cur == NULL);
                                                return error;
                                        }
                                        break;
                                }

                                /*
                                 * Split changing sb for alen and indlen since
                                 * they could be coming from different places.
                                 */
                                indlen = (xfs_extlen_t)
                                        xfs_bmap_worst_indlen(ip, alen);
                                ASSERT(indlen > 0);

                                if (rt) {
                                        error = xfs_mod_incore_sb(mp,
                                                        XFS_SBS_FREXTENTS,
                                                        -((int64_t)extsz), (flags &
                                                        XFS_BMAPI_RSVBLOCKS));
                                } else {
                                        error = xfs_mod_incore_sb(mp,
                                                        XFS_SBS_FDBLOCKS,
                                                        -((int64_t)alen), (flags &
                                                        XFS_BMAPI_RSVBLOCKS));
                                }
                                if (!error) {
                                        error = xfs_mod_incore_sb(mp,
                                                        XFS_SBS_FDBLOCKS,
                                                        -((int64_t)indlen), (flags &
                                                        XFS_BMAPI_RSVBLOCKS));
                                        if (error && rt)
                                                xfs_mod_incore_sb(mp,
                                                        XFS_SBS_FREXTENTS,
                                                        (int64_t)extsz, (flags &
                                                        XFS_BMAPI_RSVBLOCKS));
                                        else if (error)
                                                xfs_mod_incore_sb(mp,
                                                        XFS_SBS_FDBLOCKS,
                                                        (int64_t)alen, (flags &
                                                        XFS_BMAPI_RSVBLOCKS));
                                }

                                if (error) {
                                        if (XFS_IS_QUOTA_ON(mp))
                                                /* unreserve the blocks now */
                                                (void)
                                                XFS_TRANS_UNRESERVE_QUOTA_NBLKS(
                                                        mp, NULL, ip,
                                                        (long)alen, 0, rt ?
                                                        XFS_QMOPT_RES_RTBLKS :
                                                        XFS_QMOPT_RES_REGBLKS);
                                        break;
                                }

                                ip->i_delayed_blks += alen;
                                abno = NULLSTARTBLOCK(indlen);
                        } else {
                                /*
                                 * If first time, allocate and fill in
                                 * once-only bma fields.
                                 */
                                if (bma.ip == NULL) {
                                        bma.tp = tp;
                                        bma.ip = ip;
                                        bma.prevp = &prev;
                                        bma.gotp = &got;
                                        bma.total = total;
                                        bma.userdata = 0;
                                }
                                /* Indicate if this is the first user data
                                 * in the file, or just any user data.
                                 */
                                if (!(flags & XFS_BMAPI_METADATA)) {
                                        bma.userdata = (aoff == 0) ?
                                                XFS_ALLOC_INITIAL_USER_DATA :
                                                XFS_ALLOC_USERDATA;
                                }
                                /*
                                 * Fill in changeable bma fields.
                                 */
                                bma.eof = eof;
                                bma.firstblock = *firstblock;
                                bma.alen = alen;
                                bma.off = aoff;
                                bma.conv = !!(flags & XFS_BMAPI_CONVERT);
                                bma.wasdel = wasdelay;
                                bma.minlen = minlen;
                                bma.low = flist->xbf_low;
                                bma.minleft = minleft;
                                /*
                                 * Only want to do the alignment at the
                                 * eof if it is userdata and allocation length
                                 * is larger than a stripe unit.
                                 */
                                if (mp->m_dalign && alen >= mp->m_dalign &&
                                    (!(flags & XFS_BMAPI_METADATA)) &&
                                    (whichfork == XFS_DATA_FORK)) {
                                        if ((error = xfs_bmap_isaeof(ip, aoff,
                                                        whichfork, &bma.aeof)))
                                                goto error0;
                                } else
                                        bma.aeof = 0;
                                /*
                                 * Call allocator.
                                 */
                                if ((error = xfs_bmap_alloc(&bma)))
                                        goto error0;
                                /*
                                 * Copy out result fields.
                                 */
                                abno = bma.rval;
                                if ((flist->xbf_low = bma.low))
                                        minleft = 0;
                                alen = bma.alen;
                                aoff = bma.off;
                                ASSERT(*firstblock == NULLFSBLOCK ||
                                       XFS_FSB_TO_AGNO(mp, *firstblock) ==
                                       XFS_FSB_TO_AGNO(mp, bma.firstblock) ||
                                       (flist->xbf_low &&
                                        XFS_FSB_TO_AGNO(mp, *firstblock) <
                                        XFS_FSB_TO_AGNO(mp, bma.firstblock)));
                                *firstblock = bma.firstblock;
                                if (cur)
                                        cur->bc_private.b.firstblock =
                                                *firstblock;
                                if (abno == NULLFSBLOCK)
                                        break;
                                if ((ifp->if_flags & XFS_IFBROOT) && !cur) {
                                        cur = xfs_btree_init_cursor(mp,
                                                tp, NULL, 0, XFS_BTNUM_BMAP,
                                                ip, whichfork);
                                        cur->bc_private.b.firstblock =
                                                *firstblock;
                                        cur->bc_private.b.flist = flist;
                                }
                                /*
                                 * Bump the number of extents we've allocated
                                 * in this call.
                                 */
                                nallocs++;
                        }
                        if (cur)
                                cur->bc_private.b.flags =
                                        wasdelay ? XFS_BTCUR_BPRV_WASDEL : 0;
                        got.br_startoff = aoff;
                        got.br_startblock = abno;
                        got.br_blockcount = alen;
                        got.br_state = XFS_EXT_NORM;    /* assume normal */
                        /*
                         * Determine state of extent, and the filesystem.
                         * A wasdelay extent has been initialized, so
                         * shouldn't be flagged as unwritten.
                         */
                        if (wr && XFS_SB_VERSION_HASEXTFLGBIT(&mp->m_sb)) {
                                if (!wasdelay && (flags & XFS_BMAPI_PREALLOC))
                                        got.br_state = XFS_EXT_UNWRITTEN;
                        }
                        error = xfs_bmap_add_extent(ip, lastx, &cur, &got,
                                firstblock, flist, &tmp_logflags, delta,
                                whichfork, (flags & XFS_BMAPI_RSVBLOCKS));
                        logflags |= tmp_logflags;
                        if (error)
                                goto error0;
                        lastx = ifp->if_lastex;
                        ep = xfs_iext_get_ext(ifp, lastx);
                        nextents = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t);
                        xfs_bmbt_get_all(ep, &got);
                        ASSERT(got.br_startoff <= aoff);
                        ASSERT(got.br_startoff + got.br_blockcount >=
                                aoff + alen);
#ifdef DEBUG
                        if (flags & XFS_BMAPI_DELAY) {
                                ASSERT(ISNULLSTARTBLOCK(got.br_startblock));
                                ASSERT(STARTBLOCKVAL(got.br_startblock) > 0);
                        }
                        ASSERT(got.br_state == XFS_EXT_NORM ||
                               got.br_state == XFS_EXT_UNWRITTEN);
#endif
                        /*
                         * Fall down into the found allocated space case.
                         */
                } else if (inhole) {
                        /*
                         * Reading in a hole.
                         */
                        mval->br_startoff = bno;
                        mval->br_startblock = HOLESTARTBLOCK;
                        mval->br_blockcount =
                                XFS_FILBLKS_MIN(len, got.br_startoff - bno);
                        mval->br_state = XFS_EXT_NORM;
                        bno += mval->br_blockcount;
                        len -= mval->br_blockcount;
                        mval++;
                        n++;
                        continue;
                }
                /*
                 * Then deal with the allocated space we found.
                 */
                ASSERT(ep != NULL);
                if (!(flags & XFS_BMAPI_ENTIRE) &&
                    (got.br_startoff + got.br_blockcount > obno)) {
                        if (obno > bno)
                                bno = obno;
                        ASSERT((bno >= obno) || (n == 0));
                        ASSERT(bno < end);
                        mval->br_startoff = bno;
                        if (ISNULLSTARTBLOCK(got.br_startblock)) {
                                ASSERT(!wr || (flags & XFS_BMAPI_DELAY));
                                mval->br_startblock = DELAYSTARTBLOCK;
                        } else
                                mval->br_startblock =
                                        got.br_startblock +
                                        (bno - got.br_startoff);
                        /*
                         * Return the minimum of what we got and what we
                         * asked for for the length.  We can use the len
                         * variable here because it is modified below
                         * and we could have been there before coming
                         * here if the first part of the allocation
                         * didn't overlap what was asked for.
                         */
                        mval->br_blockcount =
                                XFS_FILBLKS_MIN(end - bno, got.br_blockcount -
                                        (bno - got.br_startoff));
                        mval->br_state = got.br_state;
                        ASSERT(mval->br_blockcount <= len);
                } else {
                        *mval = got;
                        if (ISNULLSTARTBLOCK(mval->br_startblock)) {
                                ASSERT(!wr || (flags & XFS_BMAPI_DELAY));
                                mval->br_startblock = DELAYSTARTBLOCK;
                        }
                }

                /*
                 * Check if writing previously allocated but
                 * unwritten extents.
                 */
                if (wr && mval->br_state == XFS_EXT_UNWRITTEN &&
                    ((flags & (XFS_BMAPI_PREALLOC|XFS_BMAPI_DELAY)) == 0)) {
                        /*
                         * Modify (by adding) the state flag, if writing.
                         */
                        ASSERT(mval->br_blockcount <= len);
                        if ((ifp->if_flags & XFS_IFBROOT) && !cur) {
                                cur = xfs_btree_init_cursor(mp,
                                        tp, NULL, 0, XFS_BTNUM_BMAP,
                                        ip, whichfork);
                                cur->bc_private.b.firstblock =
                                        *firstblock;
                                cur->bc_private.b.flist = flist;
                        }
                        mval->br_state = XFS_EXT_NORM;
                        error = xfs_bmap_add_extent(ip, lastx, &cur, mval,
                                firstblock, flist, &tmp_logflags, delta,
                                whichfork, (flags & XFS_BMAPI_RSVBLOCKS));
                        logflags |= tmp_logflags;
                        if (error)
                                goto error0;
                        lastx = ifp->if_lastex;
                        ep = xfs_iext_get_ext(ifp, lastx);
                        nextents = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t);
                        xfs_bmbt_get_all(ep, &got);
                        /*
                         * We may have combined previously unwritten
                         * space with written space, so generate
                         * another request.
                         */
                        if (mval->br_blockcount < len)
                                continue;
                }

                ASSERT((flags & XFS_BMAPI_ENTIRE) ||
                       ((mval->br_startoff + mval->br_blockcount) <= end));
                ASSERT((flags & XFS_BMAPI_ENTIRE) ||
                       (mval->br_blockcount <= len) ||
                       (mval->br_startoff < obno));
                bno = mval->br_startoff + mval->br_blockcount;
                len = end - bno;
                if (n > 0 && mval->br_startoff == mval[-1].br_startoff) {
                        ASSERT(mval->br_startblock == mval[-1].br_startblock);
                        ASSERT(mval->br_blockcount > mval[-1].br_blockcount);
                        ASSERT(mval->br_state == mval[-1].br_state);
                        mval[-1].br_blockcount = mval->br_blockcount;
                        mval[-1].br_state = mval->br_state;
                } else if (n > 0 && mval->br_startblock != DELAYSTARTBLOCK &&
                           mval[-1].br_startblock != DELAYSTARTBLOCK &&
                           mval[-1].br_startblock != HOLESTARTBLOCK &&
                           mval->br_startblock ==
                           mval[-1].br_startblock + mval[-1].br_blockcount &&
                           ((flags & XFS_BMAPI_IGSTATE) ||
                                mval[-1].br_state == mval->br_state)) {
                        ASSERT(mval->br_startoff ==
                               mval[-1].br_startoff + mval[-1].br_blockcount);
                        mval[-1].br_blockcount += mval->br_blockcount;
                } else if (n > 0 &&
                           mval->br_startblock == DELAYSTARTBLOCK &&
                           mval[-1].br_startblock == DELAYSTARTBLOCK &&
                           mval->br_startoff ==
                           mval[-1].br_startoff + mval[-1].br_blockcount) {
                        mval[-1].br_blockcount += mval->br_blockcount;
                        mval[-1].br_state = mval->br_state;
                } else if (!((n == 0) &&
                             ((mval->br_startoff + mval->br_blockcount) <=
                              obno))) {
                        mval++;
                        n++;
                }
                /*
                 * If we're done, stop now.  Stop when we've allocated
                 * XFS_BMAP_MAX_NMAP extents no matter what.  Otherwise
                 * the transaction may get too big.
                 */
                if (bno >= end || n >= *nmap || nallocs >= *nmap)
                        break;
                /*
                 * Else go on to the next record.
                 */
                ep = xfs_iext_get_ext(ifp, ++lastx);
                prev = got;
                if (lastx >= nextents)
                        eof = 1;
                else
                        xfs_bmbt_get_all(ep, &got);
        }
        ifp->if_lastex = lastx;
        *nmap = n;
        /*
         * Transform from btree to extents, give it cur.
         */
        if (tp && XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_BTREE &&
            XFS_IFORK_NEXTENTS(ip, whichfork) <= ifp->if_ext_max) {
                ASSERT(wr && cur);
                error = xfs_bmap_btree_to_extents(tp, ip, cur,
                        &tmp_logflags, whichfork);
                logflags |= tmp_logflags;
                if (error)
                        goto error0;
        }
        ASSERT(ifp->if_ext_max ==
               XFS_IFORK_SIZE(ip, whichfork) / (uint)sizeof(xfs_bmbt_rec_t));
        ASSERT(XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_BTREE ||
               XFS_IFORK_NEXTENTS(ip, whichfork) > ifp->if_ext_max);
        error = 0;
        if (delta && delta->xed_startoff != NULLFILEOFF) {
                /* A change was actually made.
                 * Note that delta->xed_blockount is an offset at this
                 * point and needs to be converted to a block count.
                 */
                ASSERT(delta->xed_blockcount > delta->xed_startoff);
                delta->xed_blockcount -= delta->xed_startoff;
        }
error0:
        /*
         * Log everything.  Do this after conversion, there's no point in
         * logging the extent records if we've converted to btree format.
         */
        if ((logflags & XFS_ILOG_FEXT(whichfork)) &&
            XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_EXTENTS)
                logflags &= ~XFS_ILOG_FEXT(whichfork);
        else if ((logflags & XFS_ILOG_FBROOT(whichfork)) &&
                 XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_BTREE)
                logflags &= ~XFS_ILOG_FBROOT(whichfork);
        /*
         * Log whatever the flags say, even if error.  Otherwise we might miss
         * detecting a case where the data is changed, there's an error,
         * and it's not logged so we don't shutdown when we should.
         */
        if (logflags) {
                ASSERT(tp && wr);
                xfs_trans_log_inode(tp, ip, logflags);
        }
        if (cur) {
                if (!error) {
                        ASSERT(*firstblock == NULLFSBLOCK ||
                               XFS_FSB_TO_AGNO(mp, *firstblock) ==
                               XFS_FSB_TO_AGNO(mp,
                                       cur->bc_private.b.firstblock) ||
                               (flist->xbf_low &&
                                XFS_FSB_TO_AGNO(mp, *firstblock) <
                                XFS_FSB_TO_AGNO(mp,
                                        cur->bc_private.b.firstblock)));
                        *firstblock = cur->bc_private.b.firstblock;
                }
                xfs_btree_del_cursor(cur,
                        error ? XFS_BTREE_ERROR : XFS_BTREE_NOERROR);
        }
        if (!error)
                xfs_bmap_validate_ret(orig_bno, orig_len, orig_flags, orig_mval,
                        orig_nmap, *nmap);
        return error;
}

/*
 * Map file blocks to filesystem blocks, simple version.
 * One block (extent) only, read-only.
 * For flags, only the XFS_BMAPI_ATTRFORK flag is examined.
 * For the other flag values, the effect is as if XFS_BMAPI_METADATA
 * was set and all the others were clear.
 */
int                                             /* error */
xfs_bmapi_single(
        xfs_trans_t     *tp,            /* transaction pointer */
        xfs_inode_t     *ip,            /* incore inode */
        int             whichfork,      /* data or attr fork */
        xfs_fsblock_t   *fsb,           /* output: mapped block */
        xfs_fileoff_t   bno)            /* starting file offs. mapped */
{
        int             eof;            /* we've hit the end of extents */
        int             error;          /* error return */
        xfs_bmbt_irec_t got;            /* current file extent record */
        xfs_ifork_t     *ifp;           /* inode fork pointer */
        xfs_extnum_t    lastx;          /* last useful extent number */
        xfs_bmbt_irec_t prev;           /* previous file extent record */

        ifp = XFS_IFORK_PTR(ip, whichfork);
        if (unlikely(
            XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_BTREE &&
            XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_EXTENTS)) {
               XFS_ERROR_REPORT("xfs_bmapi_single", XFS_ERRLEVEL_LOW,
                                ip->i_mount);
               return XFS_ERROR(EFSCORRUPTED);
        }
        if (XFS_FORCED_SHUTDOWN(ip->i_mount))
                return XFS_ERROR(EIO);
        XFS_STATS_INC(xs_blk_mapr);
        if (!(ifp->if_flags & XFS_IFEXTENTS) &&
            (error = xfs_iread_extents(tp, ip, whichfork)))
                return error;
        (void)xfs_bmap_search_extents(ip, bno, whichfork, &eof, &lastx, &got,
                &prev);
        /*
         * Reading past eof, act as though there's a hole
         * up to end.
         */
        if (eof || got.br_startoff > bno) {
                *fsb = NULLFSBLOCK;
                return 0;
        }
        ASSERT(!ISNULLSTARTBLOCK(got.br_startblock));
        ASSERT(bno < got.br_startoff + got.br_blockcount);
        *fsb = got.br_startblock + (bno - got.br_startoff);
        ifp->if_lastex = lastx;
        return 0;
}

/*
 * Unmap (remove) blocks from a file.
 * If nexts is nonzero then the number of extents to remove is limited to
 * that value.  If not all extents in the block range can be removed then
 * *done is set.
 */
int                                             /* error */
xfs_bunmapi(
        xfs_trans_t             *tp,            /* transaction pointer */
        struct xfs_inode        *ip,            /* incore inode */
        xfs_fileoff_t           bno,            /* starting offset to unmap */
        xfs_filblks_t           len,            /* length to unmap in file */
        int                     flags,          /* misc flags */
        xfs_extnum_t            nexts,          /* number of extents max */
        xfs_fsblock_t           *firstblock,    /* first allocated block
                                                   controls a.g. for allocs */
        xfs_bmap_free_t         *flist,         /* i/o: list extents to free */
        xfs_extdelta_t          *delta,         /* o: change made to incore
                                                   extents */
        int                     *done)          /* set if not done yet */
{
        xfs_btree_cur_t         *cur;           /* bmap btree cursor */
        xfs_bmbt_irec_t         del;            /* extent being deleted */
        int                     eof;            /* is deleting at eof */
        xfs_bmbt_rec_host_t     *ep;            /* extent record pointer */
        int                     error;          /* error return value */
        xfs_extnum_t            extno;          /* extent number in list */
        xfs_bmbt_irec_t         got;            /* current extent record */
        xfs_ifork_t             *ifp;           /* inode fork pointer */
        int                     isrt;           /* freeing in rt area */
        xfs_extnum_t            lastx;          /* last extent index used */
        int                     logflags;       /* transaction logging flags */
        xfs_extlen_t            mod;            /* rt extent offset */
        xfs_mount_t             *mp;            /* mount structure */
        xfs_extnum_t            nextents;       /* number of file extents */
        xfs_bmbt_irec_t         prev;           /* previous extent record */
        xfs_fileoff_t           start;          /* first file offset deleted */
        int                     tmp_logflags;   /* partial logging flags */
        int                     wasdel;         /* was a delayed alloc extent */
        int                     whichfork;      /* data or attribute fork */
        int                     rsvd;           /* OK to allocate reserved blocks */
        xfs_fsblock_t           sum;

        xfs_bunmap_trace(ip, bno, len, flags, (inst_t *)__return_address);
        whichfork = (flags & XFS_BMAPI_ATTRFORK) ?
                XFS_ATTR_FORK : XFS_DATA_FORK;
        ifp = XFS_IFORK_PTR(ip, whichfork);
        if (unlikely(
            XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_EXTENTS &&
            XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_BTREE)) {
                XFS_ERROR_REPORT("xfs_bunmapi", XFS_ERRLEVEL_LOW,
                                 ip->i_mount);
                return XFS_ERROR(EFSCORRUPTED);
        }
        mp = ip->i_mount;
        if (XFS_FORCED_SHUTDOWN(mp))
                return XFS_ERROR(EIO);
        rsvd = (flags & XFS_BMAPI_RSVBLOCKS) != 0;
        ASSERT(len > 0);
        ASSERT(nexts >= 0);
        ASSERT(ifp->if_ext_max ==
               XFS_IFORK_SIZE(ip, whichfork) / (uint)sizeof(xfs_bmbt_rec_t));
        if (!(ifp->if_flags & XFS_IFEXTENTS) &&
            (error = xfs_iread_extents(tp, ip, whichfork)))
                return error;
        nextents = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t);
        if (nextents == 0) {
                *done = 1;
                return 0;
        }
        XFS_STATS_INC(xs_blk_unmap);
        isrt = (whichfork == XFS_DATA_FORK) && XFS_IS_REALTIME_INODE(ip);
        start = bno;
        bno = start + len - 1;
        ep = xfs_bmap_search_extents(ip, bno, whichfork, &eof, &lastx, &got,
                &prev);
        if (delta) {
                delta->xed_startoff = NULLFILEOFF;
                delta->xed_blockcount = 0;
        }
        /*
         * Check to see if the given block number is past the end of the
         * file, back up to the last block if so...
         */
        if (eof) {
                ep = xfs_iext_get_ext(ifp, --lastx);
                xfs_bmbt_get_all(ep, &got);
                bno = got.br_startoff + got.br_blockcount - 1;
        }
        logflags = 0;
        if (ifp->if_flags & XFS_IFBROOT) {
                ASSERT(XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_BTREE);
                cur = xfs_btree_init_cursor(mp, tp, NULL, 0, XFS_BTNUM_BMAP, ip,
                        whichfork);
                cur->bc_private.b.firstblock = *firstblock;
                cur->bc_private.b.flist = flist;
                cur->bc_private.b.flags = 0;
        } else
                cur = NULL;
        extno = 0;
        while (bno != (xfs_fileoff_t)-1 && bno >= start && lastx >= 0 &&
               (nexts == 0 || extno < nexts)) {
                /*
                 * Is the found extent after a hole in which bno lives?
                 * Just back up to the previous extent, if so.
                 */
                if (got.br_startoff > bno) {
                        if (--lastx < 0)
                                break;
                        ep = xfs_iext_get_ext(ifp, lastx);
                        xfs_bmbt_get_all(ep, &got);
                }
                /*
                 * Is the last block of this extent before the range
                 * we're supposed to delete?  If so, we're done.
                 */
                bno = XFS_FILEOFF_MIN(bno,
                        got.br_startoff + got.br_blockcount - 1);
                if (bno < start)
                        break;
                /*
                 * Then deal with the (possibly delayed) allocated space
                 * we found.
                 */
                ASSERT(ep != NULL);
                del = got;
                wasdel = ISNULLSTARTBLOCK(del.br_startblock);
                if (got.br_startoff < start) {
                        del.br_startoff = start;
                        del.br_blockcount -= start - got.br_startoff;
                        if (!wasdel)
                                del.br_startblock += start - got.br_startoff;
                }
                if (del.br_startoff + del.br_blockcount > bno + 1)
                        del.br_blockcount = bno + 1 - del.br_startoff;
                sum = del.br_startblock + del.br_blockcount;
                if (isrt &&
                    (mod = do_mod(sum, mp->m_sb.sb_rextsize))) {
                        /*
                         * Realtime extent not lined up at the end.
                         * The extent could have been split into written
                         * and unwritten pieces, or we could just be
                         * unmapping part of it.  But we can't really
                         * get rid of part of a realtime extent.
                         */
                        if (del.br_state == XFS_EXT_UNWRITTEN ||
                            !XFS_SB_VERSION_HASEXTFLGBIT(&mp->m_sb)) {
                                /*
                                 * This piece is unwritten, or we're not
                                 * using unwritten extents.  Skip over it.
                                 */
                                ASSERT(bno >= mod);
                                bno -= mod > del.br_blockcount ?
                                        del.br_blockcount : mod;
                                if (bno < got.br_startoff) {
                                        if (--lastx >= 0)
                                                xfs_bmbt_get_all(xfs_iext_get_ext(
                                                        ifp, lastx), &got);
                                }
                                continue;
                        }
                        /*
                         * It's written, turn it unwritten.
                         * This is better than zeroing it.
                         */
                        ASSERT(del.br_state == XFS_EXT_NORM);
                        ASSERT(xfs_trans_get_block_res(tp) > 0);
                        /*
                         * If this spans a realtime extent boundary,
                         * chop it back to the start of the one we end at.
                         */
                        if (del.br_blockcount > mod) {
                                del.br_startoff += del.br_blockcount - mod;
                                del.br_startblock += del.br_blockcount - mod;
                                del.br_blockcount = mod;
                        }
                        del.br_state = XFS_EXT_UNWRITTEN;
                        error = xfs_bmap_add_extent(ip, lastx, &cur, &del,
                                firstblock, flist, &logflags, delta,
                                XFS_DATA_FORK, 0);
                        if (error)
                                goto error0;
                        goto nodelete;
                }
                if (isrt && (mod = do_mod(del.br_startblock, mp->m_sb.sb_rextsize))) {
                        /*
                         * Realtime extent is lined up at the end but not
                         * at the front.  We'll get rid of full extents if
                         * we can.
                         */
                        mod = mp->m_sb.sb_rextsize - mod;
                        if (del.br_blockcount > mod) {
                                del.br_blockcount -= mod;
                                del.br_startoff += mod;
                                del.br_startblock += mod;
                        } else if ((del.br_startoff == start &&
                                    (del.br_state == XFS_EXT_UNWRITTEN ||
                                     xfs_trans_get_block_res(tp) == 0)) ||
                                   !XFS_SB_VERSION_HASEXTFLGBIT(&mp->m_sb)) {
                                /*
                                 * Can't make it unwritten.  There isn't
                                 * a full extent here so just skip it.
                                 */
                                ASSERT(bno >= del.br_blockcount);
                                bno -= del.br_blockcount;
                                if (bno < got.br_startoff) {
                                        if (--lastx >= 0)
                                                xfs_bmbt_get_all(--ep, &got);
                                }
                                continue;
                        } else if (del.br_state == XFS_EXT_UNWRITTEN) {
                                /*
                                 * This one is already unwritten.
                                 * It must have a written left neighbor.
                                 * Unwrite the killed part of that one and
                                 * try again.
                                 */
                                ASSERT(lastx > 0);
                                xfs_bmbt_get_all(xfs_iext_get_ext(ifp,
                                                lastx - 1), &prev);
                                ASSERT(prev.br_state == XFS_EXT_NORM);
                                ASSERT(!ISNULLSTARTBLOCK(prev.br_startblock));
                                ASSERT(del.br_startblock ==
                                       prev.br_startblock + prev.br_blockcount);
                                if (prev.br_startoff < start) {
                                        mod = start - prev.br_startoff;
                                        prev.br_blockcount -= mod;
                                        prev.br_startblock += mod;
                                        prev.br_startoff = start;
                                }
                                prev.br_state = XFS_EXT_UNWRITTEN;
                                error = xfs_bmap_add_extent(ip, lastx - 1, &cur,
                                        &prev, firstblock, flist, &logflags,
                                        delta, XFS_DATA_FORK, 0);
                                if (error)
                                        goto error0;
                                goto nodelete;
                        } else {
                                ASSERT(del.br_state == XFS_EXT_NORM);
                                del.br_state = XFS_EXT_UNWRITTEN;
                                error = xfs_bmap_add_extent(ip, lastx, &cur,
                                        &del, firstblock, flist, &logflags,
                                        delta, XFS_DATA_FORK, 0);
                                if (error)
                                        goto error0;
                                goto nodelete;
                        }
                }
                if (wasdel) {
                        ASSERT(STARTBLOCKVAL(del.br_startblock) > 0);
                        /* Update realtime/data freespace, unreserve quota */
                        if (isrt) {
                                xfs_filblks_t rtexts;

                                rtexts = XFS_FSB_TO_B(mp, del.br_blockcount);
                                do_div(rtexts, mp->m_sb.sb_rextsize);
                                xfs_mod_incore_sb(mp, XFS_SBS_FREXTENTS,
                                                (int64_t)rtexts, rsvd);
                                (void)XFS_TRANS_RESERVE_QUOTA_NBLKS(mp,
                                        NULL, ip, -((long)del.br_blockcount), 0,
                                        XFS_QMOPT_RES_RTBLKS);
                        } else {
                                xfs_mod_incore_sb(mp, XFS_SBS_FDBLOCKS,
                                                (int64_t)del.br_blockcount, rsvd);
                                (void)XFS_TRANS_RESERVE_QUOTA_NBLKS(mp,
                                        NULL, ip, -((long)del.br_blockcount), 0,
                                        XFS_QMOPT_RES_REGBLKS);
                        }
                        ip->i_delayed_blks -= del.br_blockcount;
                        if (cur)
                                cur->bc_private.b.flags |=
                                        XFS_BTCUR_BPRV_WASDEL;
                } else if (cur)
                        cur->bc_private.b.flags &= ~XFS_BTCUR_BPRV_WASDEL;
                /*
                 * If it's the case where the directory code is running
                 * with no block reservation, and the deleted block is in
                 * the middle of its extent, and the resulting insert
                 * of an extent would cause transformation to btree format,
                 * then reject it.  The calling code will then swap
                 * blocks around instead.
                 * We have to do this now, rather than waiting for the
                 * conversion to btree format, since the transaction
                 * will be dirty.
                 */
                if (!wasdel && xfs_trans_get_block_res(tp) == 0 &&
                    XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_EXTENTS &&
                    XFS_IFORK_NEXTENTS(ip, whichfork) >= ifp->if_ext_max &&
                    del.br_startoff > got.br_startoff &&
                    del.br_startoff + del.br_blockcount <
                    got.br_startoff + got.br_blockcount) {
                        error = XFS_ERROR(ENOSPC);
                        goto error0;
                }
                error = xfs_bmap_del_extent(ip, tp, lastx, flist, cur, &del,
                                &tmp_logflags, delta, whichfork, rsvd);
                logflags |= tmp_logflags;
                if (error)
                        goto error0;
                bno = del.br_startoff - 1;
nodelete:
                lastx = ifp->if_lastex;
                /*
                 * If not done go on to the next (previous) record.
                 * Reset ep in case the extents array was re-alloced.
                 */
                ep = xfs_iext_get_ext(ifp, lastx);
                if (bno != (xfs_fileoff_t)-1 && bno >= start) {
                        if (lastx >= XFS_IFORK_NEXTENTS(ip, whichfork) ||
                            xfs_bmbt_get_startoff(ep) > bno) {
                                if (--lastx >= 0)
                                        ep = xfs_iext_get_ext(ifp, lastx);
                        }
                        if (lastx >= 0)
                                xfs_bmbt_get_all(ep, &got);
                        extno++;
                }
        }
        ifp->if_lastex = lastx;
        *done = bno == (xfs_fileoff_t)-1 || bno < start || lastx < 0;
        ASSERT(ifp->if_ext_max ==
               XFS_IFORK_SIZE(ip, whichfork) / (uint)sizeof(xfs_bmbt_rec_t));
        /*
         * Convert to a btree if necessary.
         */
        if (XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_EXTENTS &&
            XFS_IFORK_NEXTENTS(ip, whichfork) > ifp->if_ext_max) {
                ASSERT(cur == NULL);
                error = xfs_bmap_extents_to_btree(tp, ip, firstblock, flist,
                        &cur, 0, &tmp_logflags, whichfork);
                logflags |= tmp_logflags;
                if (error)
                        goto error0;
        }
        /*
         * transform from btree to extents, give it cur
         */
        else if (XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_BTREE &&
                 XFS_IFORK_NEXTENTS(ip, whichfork) <= ifp->if_ext_max) {
                ASSERT(cur != NULL);
                error = xfs_bmap_btree_to_extents(tp, ip, cur, &tmp_logflags,
                        whichfork);
                logflags |= tmp_logflags;
                if (error)
                        goto error0;
        }
        /*
         * transform from extents to local?
         */
        ASSERT(ifp->if_ext_max ==
               XFS_IFORK_SIZE(ip, whichfork) / (uint)sizeof(xfs_bmbt_rec_t));
        error = 0;
        if (delta && delta->xed_startoff != NULLFILEOFF) {
                /* A change was actually made.
                 * Note that delta->xed_blockount is an offset at this
                 * point and needs to be converted to a block count.
                 */
                ASSERT(delta->xed_blockcount > delta->xed_startoff);
                delta->xed_blockcount -= delta->xed_startoff;
        }
error0:
        /*
         * Log everything.  Do this after conversion, there's no point in
         * logging the extent records if we've converted to btree format.
         */
        if ((logflags & XFS_ILOG_FEXT(whichfork)) &&
            XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_EXTENTS)
                logflags &= ~XFS_ILOG_FEXT(whichfork);
        else if ((logflags & XFS_ILOG_FBROOT(whichfork)) &&
                 XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_BTREE)
                logflags &= ~XFS_ILOG_FBROOT(whichfork);
        /*
         * Log inode even in the error case, if the transaction
         * is dirty we'll need to shut down the filesystem.
         */
        if (logflags)
                xfs_trans_log_inode(tp, ip, logflags);
        if (cur) {
                if (!error) {
                        *firstblock = cur->bc_private.b.firstblock;
                        cur->bc_private.b.allocated = 0;
                }
                xfs_btree_del_cursor(cur,
                        error ? XFS_BTREE_ERROR : XFS_BTREE_NOERROR);
        }
        return error;
}

/*
 * returns 1 for success, 0 if we failed to map the extent.
 */
STATIC int
xfs_getbmapx_fix_eof_hole(
        xfs_inode_t             *ip,            /* xfs incore inode pointer */
        struct getbmap          *out,           /* output structure */
        int                     prealloced,     /* this is a file with
                                                * preallocated data space */
        __int64_t               end,            /* last block requested */
        xfs_fsblock_t           startblock)
{
        __int64_t               fixlen;
        xfs_mount_t             *mp;            /* file system mount point */

        if (startblock == HOLESTARTBLOCK) {
                mp = ip->i_mount;
                out->bmv_block = -1;
                fixlen = XFS_FSB_TO_BB(mp, XFS_B_TO_FSB(mp, ip->i_size));
                fixlen -= out->bmv_offset;
                if (prealloced && out->bmv_offset + out->bmv_length == end) {
                        /* Came to hole at EOF. Trim it. */
                        if (fixlen <= 0)
                                return 0;
                        out->bmv_length = fixlen;
                }
        } else {
                out->bmv_block = XFS_FSB_TO_DB(ip, startblock);
        }

        return 1;
}

/*
 * Fcntl interface to xfs_bmapi.
 */
int                                             /* error code */
xfs_getbmap(
        xfs_inode_t             *ip,
        struct getbmap          *bmv,           /* user bmap structure */
        void                    __user *ap,     /* pointer to user's array */
        int                     interface)      /* interface flags */
{
        __int64_t               bmvend;         /* last block requested */
        int                     error;          /* return value */
        __int64_t               fixlen;         /* length for -1 case */
        int                     i;              /* extent number */
        bhv_vnode_t             *vp;            /* corresponding vnode */
        int                     lock;           /* lock state */
        xfs_bmbt_irec_t         *map;           /* buffer for user's data */
        xfs_mount_t             *mp;            /* file system mount point */
        int                     nex;            /* # of user extents can do */
        int                     nexleft;        /* # of user extents left */
        int                     subnex;         /* # of bmapi's can do */
        int                     nmap;           /* number of map entries */
        struct getbmap          out;            /* output structure */
        int                     whichfork;      /* data or attr fork */
        int                     prealloced;     /* this is a file with
                                                 * preallocated data space */
        int                     sh_unwritten;   /* true, if unwritten */
                                                /* extents listed separately */
        int                     bmapi_flags;    /* flags for xfs_bmapi */
        __int32_t               oflags;         /* getbmapx bmv_oflags field */

        vp = XFS_ITOV(ip);
        mp = ip->i_mount;

        whichfork = interface & BMV_IF_ATTRFORK ? XFS_ATTR_FORK : XFS_DATA_FORK;
        sh_unwritten = (interface & BMV_IF_PREALLOC) != 0;

        /*      If the BMV_IF_NO_DMAPI_READ interface bit specified, do not
         *      generate a DMAPI read event.  Otherwise, if the DM_EVENT_READ
         *      bit is set for the file, generate a read event in order
         *      that the DMAPI application may do its thing before we return
         *      the extents.  Usually this means restoring user file data to
         *      regions of the file that look like holes.
         *
         *      The "old behavior" (from XFS_IOC_GETBMAP) is to not specify
         *      BMV_IF_NO_DMAPI_READ so that read events are generated.
         *      If this were not true, callers of ioctl( XFS_IOC_GETBMAP )
         *      could misinterpret holes in a DMAPI file as true holes,
         *      when in fact they may represent offline user data.
         */
        if ((interface & BMV_IF_NO_DMAPI_READ) == 0 &&
            DM_EVENT_ENABLED(ip, DM_EVENT_READ) &&
            whichfork == XFS_DATA_FORK) {
                error = XFS_SEND_DATA(mp, DM_EVENT_READ, vp, 0, 0, 0, NULL);
                if (error)
                        return XFS_ERROR(error);
        }

        if (whichfork == XFS_ATTR_FORK) {
                if (XFS_IFORK_Q(ip)) {
                        if (ip->i_d.di_aformat != XFS_DINODE_FMT_EXTENTS &&
                            ip->i_d.di_aformat != XFS_DINODE_FMT_BTREE &&
                            ip->i_d.di_aformat != XFS_DINODE_FMT_LOCAL)
                                return XFS_ERROR(EINVAL);
                } else if (unlikely(
                           ip->i_d.di_aformat != 0 &&
                           ip->i_d.di_aformat != XFS_DINODE_FMT_EXTENTS)) {
                        XFS_ERROR_REPORT("xfs_getbmap", XFS_ERRLEVEL_LOW,
                                         ip->i_mount);
                        return XFS_ERROR(EFSCORRUPTED);
                }
        } else if (ip->i_d.di_format != XFS_DINODE_FMT_EXTENTS &&
                   ip->i_d.di_format != XFS_DINODE_FMT_BTREE &&
                   ip->i_d.di_format != XFS_DINODE_FMT_LOCAL)
                return XFS_ERROR(EINVAL);
        if (whichfork == XFS_DATA_FORK) {
                if (xfs_get_extsz_hint(ip) ||
                    ip->i_d.di_flags & (XFS_DIFLAG_PREALLOC|XFS_DIFLAG_APPEND)){
                        prealloced = 1;
                        fixlen = XFS_MAXIOFFSET(mp);
                } else {
                        prealloced = 0;
                        fixlen = ip->i_size;
                }
        } else {
                prealloced = 0;
                fixlen = 1LL << 32;
        }

        if (bmv->bmv_length == -1) {
                fixlen = XFS_FSB_TO_BB(mp, XFS_B_TO_FSB(mp, fixlen));
                bmv->bmv_length = MAX( (__int64_t)(fixlen - bmv->bmv_offset),
                                        (__int64_t)0);
        } else if (bmv->bmv_length < 0)
                return XFS_ERROR(EINVAL);
        if (bmv->bmv_length == 0) {
                bmv->bmv_entries = 0;
                return 0;
        }
        nex = bmv->bmv_count - 1;
        if (nex <= 0)
                return XFS_ERROR(EINVAL);
        bmvend = bmv->bmv_offset + bmv->bmv_length;

        xfs_ilock(ip, XFS_IOLOCK_SHARED);

        if (whichfork == XFS_DATA_FORK &&
                (ip->i_delayed_blks || ip->i_size > ip->i_d.di_size)) {
                /* xfs_fsize_t last_byte = xfs_file_last_byte(ip); */
                error = xfs_flush_pages(ip, (xfs_off_t)0,
                                               -1, 0, FI_REMAPF);
        }

        ASSERT(whichfork == XFS_ATTR_FORK || ip->i_delayed_blks == 0);

        lock = xfs_ilock_map_shared(ip);

        /*
         * Don't let nex be bigger than the number of extents
         * we can have assuming alternating holes and real extents.
         */
        if (nex > XFS_IFORK_NEXTENTS(ip, whichfork) * 2 + 1)
                nex = XFS_IFORK_NEXTENTS(ip, whichfork) * 2 + 1;

        bmapi_flags = XFS_BMAPI_AFLAG(whichfork) |
                        ((sh_unwritten) ? 0 : XFS_BMAPI_IGSTATE);

        /*
         * Allocate enough space to handle "subnex" maps at a time.
         */
        subnex = 16;
        map = kmem_alloc(subnex * sizeof(*map), KM_SLEEP);

        bmv->bmv_entries = 0;

        if (XFS_IFORK_NEXTENTS(ip, whichfork) == 0) {
                error = 0;
                goto unlock_and_return;
        }

        nexleft = nex;

        do {
                nmap = (nexleft > subnex) ? subnex : nexleft;
                error = xfs_bmapi(NULL, ip, XFS_BB_TO_FSBT(mp, bmv->bmv_offset),
                                  XFS_BB_TO_FSB(mp, bmv->bmv_length),
                                  bmapi_flags, NULL, 0, map, &nmap,
                                  NULL, NULL);
                if (error)
                        goto unlock_and_return;
                ASSERT(nmap <= subnex);

                for (i = 0; i < nmap && nexleft && bmv->bmv_length; i++) {
                        nexleft--;
                        oflags = (map[i].br_state == XFS_EXT_UNWRITTEN) ?
                                        BMV_OF_PREALLOC : 0;
                        out.bmv_offset = XFS_FSB_TO_BB(mp, map[i].br_startoff);
                        out.bmv_length = XFS_FSB_TO_BB(mp, map[i].br_blockcount);
                        ASSERT(map[i].br_startblock != DELAYSTARTBLOCK);
                        if (map[i].br_startblock == HOLESTARTBLOCK &&
                            whichfork == XFS_ATTR_FORK) {
                                /* came to the end of attribute fork */
                                goto unlock_and_return;
                        } else {
                                if (!xfs_getbmapx_fix_eof_hole(ip, &out,
                                                        prealloced, bmvend,
                                                        map[i].br_startblock)) {
                                        goto unlock_and_return;
                                }

                                /* return either getbmap/getbmapx structure. */
                                if (interface & BMV_IF_EXTENDED) {
                                        struct  getbmapx        outx;

                                        GETBMAP_CONVERT(out,outx);
                                        outx.bmv_oflags = oflags;
                                        outx.bmv_unused1 = outx.bmv_unused2 = 0;
                                        if (copy_to_user(ap, &outx,
                                                        sizeof(outx))) {
                                                error = XFS_ERROR(EFAULT);
                                                goto unlock_and_return;
                                        }
                                } else {
                                        if (copy_to_user(ap, &out,
                                                        sizeof(out))) {
                                                error = XFS_ERROR(EFAULT);
                                                goto unlock_and_return;
                                        }
                                }
                                bmv->bmv_offset =
                                        out.bmv_offset + out.bmv_length;
                                bmv->bmv_length = MAX((__int64_t)0,
                                        (__int64_t)(bmvend - bmv->bmv_offset));
                                bmv->bmv_entries++;
                                ap = (interface & BMV_IF_EXTENDED) ?
                                                (void __user *)
                                        ((struct getbmapx __user *)ap + 1) :
                                                (void __user *)
                                        ((struct getbmap __user *)ap + 1);
                        }
                }
        } while (nmap && nexleft && bmv->bmv_length);

unlock_and_return:
        xfs_iunlock_map_shared(ip, lock);
        xfs_iunlock(ip, XFS_IOLOCK_SHARED);

        kmem_free(map, subnex * sizeof(*map));

        return error;
}

/*
 * Check the last inode extent to determine whether this allocation will result
 * in blocks being allocated at the end of the file. When we allocate new data
 * blocks at the end of the file which do not start at the previous data block,
 * we will try to align the new blocks at stripe unit boundaries.
 */
STATIC int                              /* error */
xfs_bmap_isaeof(
        xfs_inode_t     *ip,            /* incore inode pointer */
        xfs_fileoff_t   off,            /* file offset in fsblocks */
        int             whichfork,      /* data or attribute fork */
        char            *aeof)          /* return value */
{
        int             error;          /* error return value */
        xfs_ifork_t     *ifp;           /* inode fork pointer */
        xfs_bmbt_rec_host_t *lastrec;   /* extent record pointer */
        xfs_extnum_t    nextents;       /* number of file extents */
        xfs_bmbt_irec_t s;              /* expanded extent record */

        ASSERT(whichfork == XFS_DATA_FORK);
        ifp = XFS_IFORK_PTR(ip, whichfork);
        if (!(ifp->if_flags & XFS_IFEXTENTS) &&
            (error = xfs_iread_extents(NULL, ip, whichfork)))
                return error;
        nextents = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t);
        if (nextents == 0) {
                *aeof = 1;
                return 0;
        }
        /*
         * Go to the last extent
         */
        lastrec = xfs_iext_get_ext(ifp, nextents - 1);
        xfs_bmbt_get_all(lastrec, &s);
        /*
         * Check we are allocating in the last extent (for delayed allocations)
         * or past the last extent for non-delayed allocations.
         */
        *aeof = (off >= s.br_startoff &&
                 off < s.br_startoff + s.br_blockcount &&
                 ISNULLSTARTBLOCK(s.br_startblock)) ||
                off >= s.br_startoff + s.br_blockcount;
        return 0;
}

/*
 * Check if the endoff is outside the last extent. If so the caller will grow
 * the allocation to a stripe unit boundary.
 */
int                                     /* error */
xfs_bmap_eof(
        xfs_inode_t     *ip,            /* incore inode pointer */
        xfs_fileoff_t   endoff,         /* file offset in fsblocks */
        int             whichfork,      /* data or attribute fork */
        int             *eof)           /* result value */
{
        xfs_fsblock_t   blockcount;     /* extent block count */
        int             error;          /* error return value */
        xfs_ifork_t     *ifp;           /* inode fork pointer */
        xfs_bmbt_rec_host_t *lastrec;   /* extent record pointer */
        xfs_extnum_t    nextents;       /* number of file extents */
        xfs_fileoff_t   startoff;       /* extent starting file offset */

        ASSERT(whichfork == XFS_DATA_FORK);
        ifp = XFS_IFORK_PTR(ip, whichfork);
        if (!(ifp->if_flags & XFS_IFEXTENTS) &&
            (error = xfs_iread_extents(NULL, ip, whichfork)))
                return error;
        nextents = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t);
        if (nextents == 0) {
                *eof = 1;
                return 0;
        }
        /*
         * Go to the last extent
         */
        lastrec = xfs_iext_get_ext(ifp, nextents - 1);
        startoff = xfs_bmbt_get_startoff(lastrec);
        blockcount = xfs_bmbt_get_blockcount(lastrec);
        *eof = endoff >= startoff + blockcount;
        return 0;
}

#ifdef DEBUG
STATIC
xfs_buf_t *
xfs_bmap_get_bp(
        xfs_btree_cur_t         *cur,
        xfs_fsblock_t           bno)
{
        int i;
        xfs_buf_t *bp;

        if (!cur)
                return(NULL);

        bp = NULL;
        for(i = 0; i < XFS_BTREE_MAXLEVELS; i++) {
                bp = cur->bc_bufs[i];
                if (!bp) break;
                if (XFS_BUF_ADDR(bp) == bno)
                        break;  /* Found it */
        }
        if (i == XFS_BTREE_MAXLEVELS)
                bp = NULL;

        if (!bp) { /* Chase down all the log items to see if the bp is there */
                xfs_log_item_chunk_t    *licp;
                xfs_trans_t             *tp;

                tp = cur->bc_tp;
                licp = &tp->t_items;
                while (!bp && licp != NULL) {
                        if (XFS_LIC_ARE_ALL_FREE(licp)) {
                                licp = licp->lic_next;
                                continue;
                        }
                        for (i = 0; i < licp->lic_unused; i++) {
                                xfs_log_item_desc_t     *lidp;
                                xfs_log_item_t          *lip;
                                xfs_buf_log_item_t      *bip;
                                xfs_buf_t               *lbp;

                                if (XFS_LIC_ISFREE(licp, i)) {
                                        continue;
                                }

                                lidp = XFS_LIC_SLOT(licp, i);
                                lip = lidp->lid_item;
                                if (lip->li_type != XFS_LI_BUF)
                                        continue;

                                bip = (xfs_buf_log_item_t *)lip;
                                lbp = bip->bli_buf;

                                if (XFS_BUF_ADDR(lbp) == bno) {
                                        bp = lbp;
                                        break; /* Found it */
                                }
                        }
                        licp = licp->lic_next;
                }
        }
        return(bp);
}

void
xfs_check_block(
        xfs_bmbt_block_t        *block,
        xfs_mount_t             *mp,
        int                     root,
        short                   sz)
{
        int                     i, j, dmxr;
        __be64                  *pp, *thispa;   /* pointer to block address */
        xfs_bmbt_key_t          *prevp, *keyp;

        ASSERT(be16_to_cpu(block->bb_level) > 0);

        prevp = NULL;
        for( i = 1; i <= be16_to_cpu(block->bb_numrecs); i++) {
                dmxr = mp->m_bmap_dmxr[0];

                if (root) {
                        keyp = XFS_BMAP_BROOT_KEY_ADDR(block, i, sz);
                } else {
                        keyp = XFS_BTREE_KEY_ADDR(xfs_bmbt, block, i);
                }

                if (prevp) {
                        xfs_btree_check_key(XFS_BTNUM_BMAP, prevp, keyp);
                }
                prevp = keyp;

                /*
                 * Compare the block numbers to see if there are dups.
                 */

                if (root) {
                        pp = XFS_BMAP_BROOT_PTR_ADDR(block, i, sz);
                } else {
                        pp = XFS_BTREE_PTR_ADDR(xfs_bmbt, block, i, dmxr);
                }
                for (j = i+1; j <= be16_to_cpu(block->bb_numrecs); j++) {
                        if (root) {
                                thispa = XFS_BMAP_BROOT_PTR_ADDR(block, j, sz);
                        } else {
                                thispa = XFS_BTREE_PTR_ADDR(xfs_bmbt, block, j,
                                                            dmxr);
                        }
                        if (*thispa == *pp) {
                                cmn_err(CE_WARN, "%s: thispa(%d) == pp(%d) %Ld",
                                        __FUNCTION__, j, i,
                                        (unsigned long long)be64_to_cpu(*thispa));
                                panic("%s: ptrs are equal in node\n",
                                        __FUNCTION__);
                        }
                }
        }
}

/*
 * Check that the extents for the inode ip are in the right order in all
 * btree leaves.
 */

STATIC void
xfs_bmap_check_leaf_extents(
        xfs_btree_cur_t         *cur,   /* btree cursor or null */
        xfs_inode_t             *ip,            /* incore inode pointer */
        int                     whichfork)      /* data or attr fork */
{
        xfs_bmbt_block_t        *block; /* current btree block */
        xfs_fsblock_t           bno;    /* block # of "block" */
        xfs_buf_t               *bp;    /* buffer for "block" */
        int                     error;  /* error return value */
        xfs_extnum_t            i=0, j; /* index into the extents list */
        xfs_ifork_t             *ifp;   /* fork structure */
        int                     level;  /* btree level, for checking */
        xfs_mount_t             *mp;    /* file system mount structure */
        __be64                  *pp;    /* pointer to block address */
        xfs_bmbt_rec_t          *ep;    /* pointer to current extent */
        xfs_bmbt_rec_t          *lastp; /* pointer to previous extent */
        xfs_bmbt_rec_t          *nextp; /* pointer to next extent */
        int                     bp_release = 0;

        if (XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_BTREE) {
                return;
        }

        bno = NULLFSBLOCK;
        mp = ip->i_mount;
        ifp = XFS_IFORK_PTR(ip, whichfork);
        block = ifp->if_broot;
        /*
         * Root level must use BMAP_BROOT_PTR_ADDR macro to get ptr out.
         */
        level = be16_to_cpu(block->bb_level);
        ASSERT(level > 0);
        xfs_check_block(block, mp, 1, ifp->if_broot_bytes);
        pp = XFS_BMAP_BROOT_PTR_ADDR(block, 1, ifp->if_broot_bytes);
        bno = be64_to_cpu(*pp);

        ASSERT(bno != NULLDFSBNO);
        ASSERT(XFS_FSB_TO_AGNO(mp, bno) < mp->m_sb.sb_agcount);
        ASSERT(XFS_FSB_TO_AGBNO(mp, bno) < mp->m_sb.sb_agblocks);

        /*
         * Go down the tree until leaf level is reached, following the first
         * pointer (leftmost) at each level.
         */
        while (level-- > 0) {
                /* See if buf is in cur first */
                bp = xfs_bmap_get_bp(cur, XFS_FSB_TO_DADDR(mp, bno));
                if (bp) {
                        bp_release = 0;
                } else {
                        bp_release = 1;
                }
                if (!bp && (error = xfs_btree_read_bufl(mp, NULL, bno, 0, &bp,
                                XFS_BMAP_BTREE_REF)))
                        goto error_norelse;
                block = XFS_BUF_TO_BMBT_BLOCK(bp);
                XFS_WANT_CORRUPTED_GOTO(
                        XFS_BMAP_SANITY_CHECK(mp, block, level),
                        error0);
                if (level == 0)
                        break;

                /*
                 * Check this block for basic sanity (increasing keys and
                 * no duplicate blocks).
                 */

                xfs_check_block(block, mp, 0, 0);
                pp = XFS_BTREE_PTR_ADDR(xfs_bmbt, block, 1, mp->m_bmap_dmxr[1]);
                bno = be64_to_cpu(*pp);
                XFS_WANT_CORRUPTED_GOTO(XFS_FSB_SANITY_CHECK(mp, bno), error0);
                if (bp_release) {
                        bp_release = 0;
                        xfs_trans_brelse(NULL, bp);
                }
        }

        /*
         * Here with bp and block set to the leftmost leaf node in the tree.
         */
        i = 0;

        /*
         * Loop over all leaf nodes checking that all extents are in the right order.
         */
        lastp = NULL;
        for (;;) {
                xfs_fsblock_t   nextbno;
                xfs_extnum_t    num_recs;


                num_recs = be16_to_cpu(block->bb_numrecs);

                /*
                 * Read-ahead the next leaf block, if any.
                 */

                nextbno = be64_to_cpu(block->bb_rightsib);

                /*
                 * Check all the extents to make sure they are OK.
                 * If we had a previous block, the last entry should
                 * conform with the first entry in this one.
                 */

                ep = XFS_BTREE_REC_ADDR(xfs_bmbt, block, 1);
                for (j = 1; j < num_recs; j++) {
                        nextp = XFS_BTREE_REC_ADDR(xfs_bmbt, block, j + 1);
                        if (lastp) {
                                xfs_btree_check_rec(XFS_BTNUM_BMAP,
                                        (void *)lastp, (void *)ep);
                        }
                        xfs_btree_check_rec(XFS_BTNUM_BMAP, (void *)ep,
                                (void *)(nextp));
                        lastp = ep;
                        ep = nextp;
                }

                i += num_recs;
                if (bp_release) {
                        bp_release = 0;
                        xfs_trans_brelse(NULL, bp);
                }
                bno = nextbno;
                /*
                 * If we've reached the end, stop.
                 */
                if (bno == NULLFSBLOCK)
                        break;

                bp = xfs_bmap_get_bp(cur, XFS_FSB_TO_DADDR(mp, bno));
                if (bp) {
                        bp_release = 0;
                } else {
                        bp_release = 1;
                }
                if (!bp && (error = xfs_btree_read_bufl(mp, NULL, bno, 0, &bp,
                                XFS_BMAP_BTREE_REF)))
                        goto error_norelse;
                block = XFS_BUF_TO_BMBT_BLOCK(bp);
        }
        if (bp_release) {
                bp_release = 0;
                xfs_trans_brelse(NULL, bp);
        }
        return;

error0:
        cmn_err(CE_WARN, "%s: at error0", __FUNCTION__);
        if (bp_release)
                xfs_trans_brelse(NULL, bp);
error_norelse:
        cmn_err(CE_WARN, "%s: BAD after btree leaves for %d extents",
                __FUNCTION__, i);
        panic("%s: CORRUPTED BTREE OR SOMETHING", __FUNCTION__);
        return;
}
#endif

/*
 * Count fsblocks of the given fork.
 */
int                                             /* error */
xfs_bmap_count_blocks(
        xfs_trans_t             *tp,            /* transaction pointer */
        xfs_inode_t             *ip,            /* incore inode */
        int                     whichfork,      /* data or attr fork */
        int                     *count)         /* out: count of blocks */
{
        xfs_bmbt_block_t        *block; /* current btree block */
        xfs_fsblock_t           bno;    /* block # of "block" */
        xfs_ifork_t             *ifp;   /* fork structure */
        int                     level;  /* btree level, for checking */
        xfs_mount_t             *mp;    /* file system mount structure */
        __be64                  *pp;    /* pointer to block address */

        bno = NULLFSBLOCK;
        mp = ip->i_mount;
        ifp = XFS_IFORK_PTR(ip, whichfork);
        if ( XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_EXTENTS ) {
                if (unlikely(xfs_bmap_count_leaves(ifp, 0,
                        ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t),
                        count) < 0)) {
                        XFS_ERROR_REPORT("xfs_bmap_count_blocks(1)",
                                         XFS_ERRLEVEL_LOW, mp);
                        return XFS_ERROR(EFSCORRUPTED);
                }
                return 0;
        }

        /*
         * Root level must use BMAP_BROOT_PTR_ADDR macro to get ptr out.
         */
        block = ifp->if_broot;
        level = be16_to_cpu(block->bb_level);
        ASSERT(level > 0);
        pp = XFS_BMAP_BROOT_PTR_ADDR(block, 1, ifp->if_broot_bytes);
        bno = be64_to_cpu(*pp);
        ASSERT(bno != NULLDFSBNO);
        ASSERT(XFS_FSB_TO_AGNO(mp, bno) < mp->m_sb.sb_agcount);
        ASSERT(XFS_FSB_TO_AGBNO(mp, bno) < mp->m_sb.sb_agblocks);

        if (unlikely(xfs_bmap_count_tree(mp, tp, ifp, bno, level, count) < 0)) {
                XFS_ERROR_REPORT("xfs_bmap_count_blocks(2)", XFS_ERRLEVEL_LOW,
                                 mp);
                return XFS_ERROR(EFSCORRUPTED);
        }

        return 0;
}

/*
 * Recursively walks each level of a btree
 * to count total fsblocks is use.
 */
int                                     /* error */
xfs_bmap_count_tree(
        xfs_mount_t     *mp,            /* file system mount point */
        xfs_trans_t     *tp,            /* transaction pointer */
        xfs_ifork_t     *ifp,           /* inode fork pointer */
        xfs_fsblock_t   blockno,        /* file system block number */
        int             levelin,        /* level in btree */
        int             *count)         /* Count of blocks */
{
        int                     error;
        xfs_buf_t               *bp, *nbp;
        int                     level = levelin;
        __be64                  *pp;
        xfs_fsblock_t           bno = blockno;
        xfs_fsblock_t           nextbno;
        xfs_bmbt_block_t        *block, *nextblock;
        int                     numrecs;

        if ((error = xfs_btree_read_bufl(mp, tp, bno, 0, &bp, XFS_BMAP_BTREE_REF)))
                return error;
        *count += 1;
        block = XFS_BUF_TO_BMBT_BLOCK(bp);

        if (--level) {
                /* Not at node above leafs, count this level of nodes */
                nextbno = be64_to_cpu(block->bb_rightsib);
                while (nextbno != NULLFSBLOCK) {
                        if ((error = xfs_btree_read_bufl(mp, tp, nextbno,
                                0, &nbp, XFS_BMAP_BTREE_REF)))
                                return error;
                        *count += 1;
                        nextblock = XFS_BUF_TO_BMBT_BLOCK(nbp);
                        nextbno = be64_to_cpu(nextblock->bb_rightsib);
                        xfs_trans_brelse(tp, nbp);
                }

                /* Dive to the next level */
                pp = XFS_BTREE_PTR_ADDR(xfs_bmbt, block, 1, mp->m_bmap_dmxr[1]);
                bno = be64_to_cpu(*pp);
                if (unlikely((error =
                     xfs_bmap_count_tree(mp, tp, ifp, bno, level, count)) < 0)) {
                        xfs_trans_brelse(tp, bp);
                        XFS_ERROR_REPORT("xfs_bmap_count_tree(1)",
                                         XFS_ERRLEVEL_LOW, mp);
                        return XFS_ERROR(EFSCORRUPTED);
                }
                xfs_trans_brelse(tp, bp);
        } else {
                /* count all level 1 nodes and their leaves */
                for (;;) {
                        nextbno = be64_to_cpu(block->bb_rightsib);
                        numrecs = be16_to_cpu(block->bb_numrecs);
                        if (unlikely(xfs_bmap_disk_count_leaves(0,
                                        block, numrecs, count) < 0)) {
                                xfs_trans_brelse(tp, bp);
                                XFS_ERROR_REPORT("xfs_bmap_count_tree(2)",
                                                 XFS_ERRLEVEL_LOW, mp);
                                return XFS_ERROR(EFSCORRUPTED);
                        }
                        xfs_trans_brelse(tp, bp);
                        if (nextbno == NULLFSBLOCK)
                                break;
                        bno = nextbno;
                        if ((error = xfs_btree_read_bufl(mp, tp, bno, 0, &bp,
                                XFS_BMAP_BTREE_REF)))
                                return error;
                        *count += 1;
                        block = XFS_BUF_TO_BMBT_BLOCK(bp);
                }
        }
        return 0;
}

/*
 * Count leaf blocks given a range of extent records.
 */
int
xfs_bmap_count_leaves(
        xfs_ifork_t             *ifp,
        xfs_extnum_t            idx,
        int                     numrecs,
        int                     *count)
{
        int             b;

        for (b = 0; b < numrecs; b++) {
                xfs_bmbt_rec_host_t *frp = xfs_iext_get_ext(ifp, idx + b);
                *count += xfs_bmbt_get_blockcount(frp);
        }
        return 0;
}

/*
 * Count leaf blocks given a range of extent records originally
 * in btree format.
 */
int
xfs_bmap_disk_count_leaves(
        xfs_extnum_t            idx,
        xfs_bmbt_block_t        *block,
        int                     numrecs,
        int                     *count)
{
        int             b;
        xfs_bmbt_rec_t  *frp;

        for (b = 1; b <= numrecs; b++) {
                frp = XFS_BTREE_REC_ADDR(xfs_bmbt, block, idx + b);
                *count += xfs_bmbt_disk_get_blockcount(frp);
        }
        return 0;
}