git.oblomov.eu Git - linux-2.6/blob - fs/xfs/xfs_fsops.c

   1 /*
   2  * Copyright (c) 2000-2005 Silicon Graphics, Inc.
   3  * All Rights Reserved.
   4  *
   5  * This program is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU General Public License as
   7  * published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it would be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write the Free Software Foundation,
  16  * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  17  */
  18 #include "xfs.h"
  19 #include "xfs_fs.h"
  20 #include "xfs_types.h"
  21 #include "xfs_bit.h"
  22 #include "xfs_inum.h"
  23 #include "xfs_log.h"
  24 #include "xfs_trans.h"
  25 #include "xfs_sb.h"
  26 #include "xfs_ag.h"
  27 #include "xfs_dir2.h"
  28 #include "xfs_dmapi.h"
  29 #include "xfs_mount.h"
  30 #include "xfs_bmap_btree.h"
  31 #include "xfs_alloc_btree.h"
  32 #include "xfs_ialloc_btree.h"
  33 #include "xfs_dir2_sf.h"
  34 #include "xfs_attr_sf.h"
  35 #include "xfs_dinode.h"
  36 #include "xfs_inode.h"
  37 #include "xfs_inode_item.h"
  38 #include "xfs_btree.h"
  39 #include "xfs_error.h"
  40 #include "xfs_alloc.h"
  41 #include "xfs_ialloc.h"
  42 #include "xfs_fsops.h"
  43 #include "xfs_itable.h"
  44 #include "xfs_trans_space.h"
  45 #include "xfs_rtalloc.h"
  46 #include "xfs_rw.h"
  47
  48 /*
  49  * File system operations
  50  */
  51
  52 int
  53 xfs_fs_geometry(
  54         xfs_mount_t             *mp,
  55         xfs_fsop_geom_t         *geo,
  56         int                     new_version)
  57 {
  58         geo->blocksize = mp->m_sb.sb_blocksize;
  59         geo->rtextsize = mp->m_sb.sb_rextsize;
  60         geo->agblocks = mp->m_sb.sb_agblocks;
  61         geo->agcount = mp->m_sb.sb_agcount;
  62         geo->logblocks = mp->m_sb.sb_logblocks;
  63         geo->sectsize = mp->m_sb.sb_sectsize;
  64         geo->inodesize = mp->m_sb.sb_inodesize;
  65         geo->imaxpct = mp->m_sb.sb_imax_pct;
  66         geo->datablocks = mp->m_sb.sb_dblocks;
  67         geo->rtblocks = mp->m_sb.sb_rblocks;
  68         geo->rtextents = mp->m_sb.sb_rextents;
  69         geo->logstart = mp->m_sb.sb_logstart;
  70         ASSERT(sizeof(geo->uuid)==sizeof(mp->m_sb.sb_uuid));
  71         memcpy(geo->uuid, &mp->m_sb.sb_uuid, sizeof(mp->m_sb.sb_uuid));
  72         if (new_version >= 2) {
  73                 geo->sunit = mp->m_sb.sb_unit;
  74                 geo->swidth = mp->m_sb.sb_width;
  75         }
  76         if (new_version >= 3) {
  77                 geo->version = XFS_FSOP_GEOM_VERSION;
  78                 geo->flags =
  79                         (XFS_SB_VERSION_HASATTR(&mp->m_sb) ?
  80                                 XFS_FSOP_GEOM_FLAGS_ATTR : 0) |
  81                         (XFS_SB_VERSION_HASNLINK(&mp->m_sb) ?
  82                                 XFS_FSOP_GEOM_FLAGS_NLINK : 0) |
  83                         (XFS_SB_VERSION_HASQUOTA(&mp->m_sb) ?
  84                                 XFS_FSOP_GEOM_FLAGS_QUOTA : 0) |
  85                         (XFS_SB_VERSION_HASALIGN(&mp->m_sb) ?
  86                                 XFS_FSOP_GEOM_FLAGS_IALIGN : 0) |
  87                         (XFS_SB_VERSION_HASDALIGN(&mp->m_sb) ?
  88                                 XFS_FSOP_GEOM_FLAGS_DALIGN : 0) |
  89                         (XFS_SB_VERSION_HASSHARED(&mp->m_sb) ?
  90                                 XFS_FSOP_GEOM_FLAGS_SHARED : 0) |
  91                         (XFS_SB_VERSION_HASEXTFLGBIT(&mp->m_sb) ?
  92                                 XFS_FSOP_GEOM_FLAGS_EXTFLG : 0) |
  93                         (XFS_SB_VERSION_HASDIRV2(&mp->m_sb) ?
  94                                 XFS_FSOP_GEOM_FLAGS_DIRV2 : 0) |
  95                         (XFS_SB_VERSION_HASSECTOR(&mp->m_sb) ?
  96                                 XFS_FSOP_GEOM_FLAGS_SECTOR : 0) |
  97                         (XFS_SB_VERSION_HASATTR2(&mp->m_sb) ?
  98                                 XFS_FSOP_GEOM_FLAGS_ATTR2 : 0);
  99                 geo->logsectsize = XFS_SB_VERSION_HASSECTOR(&mp->m_sb) ?
 100                                 mp->m_sb.sb_logsectsize : BBSIZE;
 101                 geo->rtsectsize = mp->m_sb.sb_blocksize;
 102                 geo->dirblocksize = mp->m_dirblksize;
 103         }
 104         if (new_version >= 4) {
 105                 geo->flags |=
 106                         (XFS_SB_VERSION_HASLOGV2(&mp->m_sb) ?
 107                                 XFS_FSOP_GEOM_FLAGS_LOGV2 : 0);
 108                 geo->logsunit = mp->m_sb.sb_logsunit;
 109         }
 110         return 0;
 111 }
 112
 113 static int
 114 xfs_growfs_data_private(
 115         xfs_mount_t             *mp,            /* mount point for filesystem */
 116         xfs_growfs_data_t       *in)            /* growfs data input struct */
 117 {
 118         xfs_agf_t               *agf;
 119         xfs_agi_t               *agi;
 120         xfs_agnumber_t          agno;
 121         xfs_extlen_t            agsize;
 122         xfs_extlen_t            tmpsize;
 123         xfs_alloc_rec_t         *arec;
 124         xfs_btree_sblock_t      *block;
 125         xfs_buf_t               *bp;
 126         int                     bucket;
 127         int                     dpct;
 128         int                     error;
 129         xfs_agnumber_t          nagcount;
 130         xfs_agnumber_t          nagimax = 0;
 131         xfs_rfsblock_t          nb, nb_mod;
 132         xfs_rfsblock_t          new;
 133         xfs_rfsblock_t          nfree;
 134         xfs_agnumber_t          oagcount;
 135         int                     pct;
 136         xfs_sb_t                *sbp;
 137         xfs_trans_t             *tp;
 138
 139         nb = in->newblocks;
 140         pct = in->imaxpct;
 141         if (nb < mp->m_sb.sb_dblocks || pct < 0 || pct > 100)
 142                 return XFS_ERROR(EINVAL);
 143         dpct = pct - mp->m_sb.sb_imax_pct;
 144         error = xfs_read_buf(mp, mp->m_ddev_targp,
 145                         XFS_FSB_TO_BB(mp, nb) - XFS_FSS_TO_BB(mp, 1),
 146                         XFS_FSS_TO_BB(mp, 1), 0, &bp);
 147         if (error)
 148                 return error;
 149         ASSERT(bp);
 150         xfs_buf_relse(bp);
 151
 152         new = nb;       /* use new as a temporary here */
 153         nb_mod = do_div(new, mp->m_sb.sb_agblocks);
 154         nagcount = new + (nb_mod != 0);
 155         if (nb_mod && nb_mod < XFS_MIN_AG_BLOCKS) {
 156                 nagcount--;
 157                 nb = nagcount * mp->m_sb.sb_agblocks;
 158                 if (nb < mp->m_sb.sb_dblocks)
 159                         return XFS_ERROR(EINVAL);
 160         }
 161         new = nb - mp->m_sb.sb_dblocks;
 162         oagcount = mp->m_sb.sb_agcount;
 163         if (nagcount > oagcount) {
 164                 down_write(&mp->m_peraglock);
 165                 mp->m_perag = kmem_realloc(mp->m_perag,
 166                         sizeof(xfs_perag_t) * nagcount,
 167                         sizeof(xfs_perag_t) * oagcount,
 168                         KM_SLEEP);
 169                 memset(&mp->m_perag[oagcount], 0,
 170                         (nagcount - oagcount) * sizeof(xfs_perag_t));
 171                 mp->m_flags |= XFS_MOUNT_32BITINODES;
 172                 nagimax = xfs_initialize_perag(XFS_MTOVFS(mp), mp, nagcount);
 173                 up_write(&mp->m_peraglock);
 174         }
 175         tp = xfs_trans_alloc(mp, XFS_TRANS_GROWFS);
 176         if ((error = xfs_trans_reserve(tp, XFS_GROWFS_SPACE_RES(mp),
 177                         XFS_GROWDATA_LOG_RES(mp), 0, 0, 0))) {
 178                 xfs_trans_cancel(tp, 0);
 179                 return error;
 180         }
 181
 182         nfree = 0;
 183         for (agno = nagcount - 1; agno >= oagcount; agno--, new -= agsize) {
 184                 /*
 185                  * AG freelist header block
 186                  */
 187                 bp = xfs_buf_get(mp->m_ddev_targp,
 188                                   XFS_AG_DADDR(mp, agno, XFS_AGF_DADDR(mp)),
 189                                   XFS_FSS_TO_BB(mp, 1), 0);
 190                 agf = XFS_BUF_TO_AGF(bp);
 191                 memset(agf, 0, mp->m_sb.sb_sectsize);
 192                 agf->agf_magicnum = cpu_to_be32(XFS_AGF_MAGIC);
 193                 agf->agf_versionnum = cpu_to_be32(XFS_AGF_VERSION);
 194                 agf->agf_seqno = cpu_to_be32(agno);
 195                 if (agno == nagcount - 1)
 196                         agsize =
 197                                 nb -
 198                                 (agno * (xfs_rfsblock_t)mp->m_sb.sb_agblocks);
 199                 else
 200                         agsize = mp->m_sb.sb_agblocks;
 201                 agf->agf_length = cpu_to_be32(agsize);
 202                 agf->agf_roots[XFS_BTNUM_BNOi] = cpu_to_be32(XFS_BNO_BLOCK(mp));
 203                 agf->agf_roots[XFS_BTNUM_CNTi] = cpu_to_be32(XFS_CNT_BLOCK(mp));
 204                 agf->agf_levels[XFS_BTNUM_BNOi] = cpu_to_be32(1);
 205                 agf->agf_levels[XFS_BTNUM_CNTi] = cpu_to_be32(1);
 206                 agf->agf_flfirst = 0;
 207                 agf->agf_fllast = cpu_to_be32(XFS_AGFL_SIZE(mp) - 1);
 208                 agf->agf_flcount = 0;
 209                 tmpsize = agsize - XFS_PREALLOC_BLOCKS(mp);
 210                 agf->agf_freeblks = cpu_to_be32(tmpsize);
 211                 agf->agf_longest = cpu_to_be32(tmpsize);
 212                 error = xfs_bwrite(mp, bp);
 213                 if (error) {
 214                         goto error0;
 215                 }
 216                 /*
 217                  * AG inode header block
 218                  */
 219                 bp = xfs_buf_get(mp->m_ddev_targp,
 220                                   XFS_AG_DADDR(mp, agno, XFS_AGI_DADDR(mp)),
 221                                   XFS_FSS_TO_BB(mp, 1), 0);
 222                 agi = XFS_BUF_TO_AGI(bp);
 223                 memset(agi, 0, mp->m_sb.sb_sectsize);
 224                 agi->agi_magicnum = cpu_to_be32(XFS_AGI_MAGIC);
 225                 agi->agi_versionnum = cpu_to_be32(XFS_AGI_VERSION);
 226                 agi->agi_seqno = cpu_to_be32(agno);
 227                 agi->agi_length = cpu_to_be32(agsize);
 228                 agi->agi_count = 0;
 229                 agi->agi_root = cpu_to_be32(XFS_IBT_BLOCK(mp));
 230                 agi->agi_level = cpu_to_be32(1);
 231                 agi->agi_freecount = 0;
 232                 agi->agi_newino = cpu_to_be32(NULLAGINO);
 233                 agi->agi_dirino = cpu_to_be32(NULLAGINO);
 234                 for (bucket = 0; bucket < XFS_AGI_UNLINKED_BUCKETS; bucket++)
 235                         agi->agi_unlinked[bucket] = cpu_to_be32(NULLAGINO);
 236                 error = xfs_bwrite(mp, bp);
 237                 if (error) {
 238                         goto error0;
 239                 }
 240                 /*
 241                  * BNO btree root block
 242                  */
 243                 bp = xfs_buf_get(mp->m_ddev_targp,
 244                         XFS_AGB_TO_DADDR(mp, agno, XFS_BNO_BLOCK(mp)),
 245                         BTOBB(mp->m_sb.sb_blocksize), 0);
 246                 block = XFS_BUF_TO_SBLOCK(bp);
 247                 memset(block, 0, mp->m_sb.sb_blocksize);
 248                 block->bb_magic = cpu_to_be32(XFS_ABTB_MAGIC);
 249                 block->bb_level = 0;
 250                 block->bb_numrecs = cpu_to_be16(1);
 251                 block->bb_leftsib = cpu_to_be32(NULLAGBLOCK);
 252                 block->bb_rightsib = cpu_to_be32(NULLAGBLOCK);
 253                 arec = XFS_BTREE_REC_ADDR(mp->m_sb.sb_blocksize, xfs_alloc,
 254                         block, 1, mp->m_alloc_mxr[0]);
 255                 arec->ar_startblock = cpu_to_be32(XFS_PREALLOC_BLOCKS(mp));
 256                 arec->ar_blockcount = cpu_to_be32(
 257                         agsize - be32_to_cpu(arec->ar_startblock));
 258                 error = xfs_bwrite(mp, bp);
 259                 if (error) {
 260                         goto error0;
 261                 }
 262                 /*
 263                  * CNT btree root block
 264                  */
 265                 bp = xfs_buf_get(mp->m_ddev_targp,
 266                         XFS_AGB_TO_DADDR(mp, agno, XFS_CNT_BLOCK(mp)),
 267                         BTOBB(mp->m_sb.sb_blocksize), 0);
 268                 block = XFS_BUF_TO_SBLOCK(bp);
 269                 memset(block, 0, mp->m_sb.sb_blocksize);
 270                 block->bb_magic = cpu_to_be32(XFS_ABTC_MAGIC);
 271                 block->bb_level = 0;
 272                 block->bb_numrecs = cpu_to_be16(1);
 273                 block->bb_leftsib = cpu_to_be32(NULLAGBLOCK);
 274                 block->bb_rightsib = cpu_to_be32(NULLAGBLOCK);
 275                 arec = XFS_BTREE_REC_ADDR(mp->m_sb.sb_blocksize, xfs_alloc,
 276                         block, 1, mp->m_alloc_mxr[0]);
 277                 arec->ar_startblock = cpu_to_be32(XFS_PREALLOC_BLOCKS(mp));
 278                 arec->ar_blockcount = cpu_to_be32(
 279                         agsize - be32_to_cpu(arec->ar_startblock));
 280                 nfree += be32_to_cpu(arec->ar_blockcount);
 281                 error = xfs_bwrite(mp, bp);
 282                 if (error) {
 283                         goto error0;
 284                 }
 285                 /*
 286                  * INO btree root block
 287                  */
 288                 bp = xfs_buf_get(mp->m_ddev_targp,
 289                         XFS_AGB_TO_DADDR(mp, agno, XFS_IBT_BLOCK(mp)),
 290                         BTOBB(mp->m_sb.sb_blocksize), 0);
 291                 block = XFS_BUF_TO_SBLOCK(bp);
 292                 memset(block, 0, mp->m_sb.sb_blocksize);
 293                 block->bb_magic = cpu_to_be32(XFS_IBT_MAGIC);
 294                 block->bb_level = 0;
 295                 block->bb_numrecs = 0;
 296                 block->bb_leftsib = cpu_to_be32(NULLAGBLOCK);
 297                 block->bb_rightsib = cpu_to_be32(NULLAGBLOCK);
 298                 error = xfs_bwrite(mp, bp);
 299                 if (error) {
 300                         goto error0;
 301                 }
 302         }
 303         xfs_trans_agblocks_delta(tp, nfree);
 304         /*
 305          * There are new blocks in the old last a.g.
 306          */
 307         if (new) {
 308                 /*
 309                  * Change the agi length.
 310                  */
 311                 error = xfs_ialloc_read_agi(mp, tp, agno, &bp);
 312                 if (error) {
 313                         goto error0;
 314                 }
 315                 ASSERT(bp);
 316                 agi = XFS_BUF_TO_AGI(bp);
 317                 be32_add(&agi->agi_length, new);
 318                 ASSERT(nagcount == oagcount ||
 319                        be32_to_cpu(agi->agi_length) == mp->m_sb.sb_agblocks);
 320                 xfs_ialloc_log_agi(tp, bp, XFS_AGI_LENGTH);
 321                 /*
 322                  * Change agf length.
 323                  */
 324                 error = xfs_alloc_read_agf(mp, tp, agno, 0, &bp);
 325                 if (error) {
 326                         goto error0;
 327                 }
 328                 ASSERT(bp);
 329                 agf = XFS_BUF_TO_AGF(bp);
 330                 be32_add(&agf->agf_length, new);
 331                 ASSERT(be32_to_cpu(agf->agf_length) ==
 332                        be32_to_cpu(agi->agi_length));
 333                 /*
 334                  * Free the new space.
 335                  */
 336                 error = xfs_free_extent(tp, XFS_AGB_TO_FSB(mp, agno,
 337                         be32_to_cpu(agf->agf_length) - new), new);
 338                 if (error) {
 339                         goto error0;
 340                 }
 341         }
 342         if (nagcount > oagcount)
 343                 xfs_trans_mod_sb(tp, XFS_TRANS_SB_AGCOUNT, nagcount - oagcount);
 344         if (nb > mp->m_sb.sb_dblocks)
 345                 xfs_trans_mod_sb(tp, XFS_TRANS_SB_DBLOCKS,
 346                                  nb - mp->m_sb.sb_dblocks);
 347         if (nfree)
 348                 xfs_trans_mod_sb(tp, XFS_TRANS_SB_FDBLOCKS, nfree);
 349         if (dpct)
 350                 xfs_trans_mod_sb(tp, XFS_TRANS_SB_IMAXPCT, dpct);
 351         error = xfs_trans_commit(tp, 0, NULL);
 352         if (error) {
 353                 return error;
 354         }
 355         /* New allocation groups fully initialized, so update mount struct */
 356         if (nagimax)
 357                 mp->m_maxagi = nagimax;
 358         if (mp->m_sb.sb_imax_pct) {
 359                 __uint64_t icount = mp->m_sb.sb_dblocks * mp->m_sb.sb_imax_pct;
 360                 do_div(icount, 100);
 361                 mp->m_maxicount = icount << mp->m_sb.sb_inopblog;
 362         } else
 363                 mp->m_maxicount = 0;
 364         for (agno = 1; agno < nagcount; agno++) {
 365                 error = xfs_read_buf(mp, mp->m_ddev_targp,
 366                                   XFS_AGB_TO_DADDR(mp, agno, XFS_SB_BLOCK(mp)),
 367                                   XFS_FSS_TO_BB(mp, 1), 0, &bp);
 368                 if (error) {
 369                         xfs_fs_cmn_err(CE_WARN, mp,
 370                         "error %d reading secondary superblock for ag %d",
 371                                 error, agno);
 372                         break;
 373                 }
 374                 sbp = XFS_BUF_TO_SBP(bp);
 375                 xfs_xlatesb(sbp, &mp->m_sb, -1, XFS_SB_ALL_BITS);
 376                 /*
 377                  * If we get an error writing out the alternate superblocks,
 378                  * just issue a warning and continue.  The real work is
 379                  * already done and committed.
 380                  */
 381                 if (!(error = xfs_bwrite(mp, bp))) {
 382                         continue;
 383                 } else {
 384                         xfs_fs_cmn_err(CE_WARN, mp,
 385                 "write error %d updating secondary superblock for ag %d",
 386                                 error, agno);
 387                         break; /* no point in continuing */
 388                 }
 389         }
 390         return 0;
 391
 392  error0:
 393         xfs_trans_cancel(tp, XFS_TRANS_ABORT);
 394         return error;
 395 }
 396
 397 static int
 398 xfs_growfs_log_private(
 399         xfs_mount_t             *mp,    /* mount point for filesystem */
 400         xfs_growfs_log_t        *in)    /* growfs log input struct */
 401 {
 402         xfs_extlen_t            nb;
 403
 404         nb = in->newblocks;
 405         if (nb < XFS_MIN_LOG_BLOCKS || nb < XFS_B_TO_FSB(mp, XFS_MIN_LOG_BYTES))
 406                 return XFS_ERROR(EINVAL);
 407         if (nb == mp->m_sb.sb_logblocks &&
 408             in->isint == (mp->m_sb.sb_logstart != 0))
 409                 return XFS_ERROR(EINVAL);
 410         /*
 411          * Moving the log is hard, need new interfaces to sync
 412          * the log first, hold off all activity while moving it.
 413          * Can have shorter or longer log in the same space,
 414          * or transform internal to external log or vice versa.
 415          */
 416         return XFS_ERROR(ENOSYS);
 417 }
 418
 419 /*
 420  * protected versions of growfs function acquire and release locks on the mount
 421  * point - exported through ioctls: XFS_IOC_FSGROWFSDATA, XFS_IOC_FSGROWFSLOG,
 422  * XFS_IOC_FSGROWFSRT
 423  */
 424
 425
 426 int
 427 xfs_growfs_data(
 428         xfs_mount_t             *mp,
 429         xfs_growfs_data_t       *in)
 430 {
 431         int error;
 432         if (!cpsema(&mp->m_growlock))
 433                 return XFS_ERROR(EWOULDBLOCK);
 434         error = xfs_growfs_data_private(mp, in);
 435         vsema(&mp->m_growlock);
 436         return error;
 437 }
 438
 439 int
 440 xfs_growfs_log(
 441         xfs_mount_t             *mp,
 442         xfs_growfs_log_t        *in)
 443 {
 444         int error;
 445         if (!cpsema(&mp->m_growlock))
 446                 return XFS_ERROR(EWOULDBLOCK);
 447         error = xfs_growfs_log_private(mp, in);
 448         vsema(&mp->m_growlock);
 449         return error;
 450 }
 451
 452 /*
 453  * exported through ioctl XFS_IOC_FSCOUNTS
 454  */
 455
 456 int
 457 xfs_fs_counts(
 458         xfs_mount_t             *mp,
 459         xfs_fsop_counts_t       *cnt)
 460 {
 461         unsigned long   s;
 462
 463         xfs_icsb_sync_counters_lazy(mp);
 464         s = XFS_SB_LOCK(mp);
 465         cnt->freedata = mp->m_sb.sb_fdblocks - XFS_ALLOC_SET_ASIDE(mp);
 466         cnt->freertx = mp->m_sb.sb_frextents;
 467         cnt->freeino = mp->m_sb.sb_ifree;
 468         cnt->allocino = mp->m_sb.sb_icount;
 469         XFS_SB_UNLOCK(mp, s);
 470         return 0;
 471 }
 472
 473 /*
 474  * exported through ioctl XFS_IOC_SET_RESBLKS & XFS_IOC_GET_RESBLKS
 475  *
 476  * xfs_reserve_blocks is called to set m_resblks
 477  * in the in-core mount table. The number of unused reserved blocks
 478  * is kept in m_resblks_avail.
 479  *
 480  * Reserve the requested number of blocks if available. Otherwise return
 481  * as many as possible to satisfy the request. The actual number
 482  * reserved are returned in outval
 483  *
 484  * A null inval pointer indicates that only the current reserved blocks
 485  * available  should  be returned no settings are changed.
 486  */
 487
 488 int
 489 xfs_reserve_blocks(
 490         xfs_mount_t             *mp,
 491         __uint64_t              *inval,
 492         xfs_fsop_resblks_t      *outval)
 493 {
 494         __int64_t               lcounter, delta;
 495         __uint64_t              request;
 496         unsigned long           s;
 497
 498         /* If inval is null, report current values and return */
 499
 500         if (inval == (__uint64_t *)NULL) {
 501                 outval->resblks = mp->m_resblks;
 502                 outval->resblks_avail = mp->m_resblks_avail;
 503                 return 0;
 504         }
 505
 506         request = *inval;
 507         s = XFS_SB_LOCK(mp);
 508
 509         /*
 510          * If our previous reservation was larger than the current value,
 511          * then move any unused blocks back to the free pool.
 512          */
 513
 514         if (mp->m_resblks > request) {
 515                 lcounter = mp->m_resblks_avail - request;
 516                 if (lcounter  > 0) {            /* release unused blocks */
 517                         mp->m_sb.sb_fdblocks += lcounter;
 518                         mp->m_resblks_avail -= lcounter;
 519                 }
 520                 mp->m_resblks = request;
 521         } else {
 522                 __int64_t       free;
 523
 524                 free =  mp->m_sb.sb_fdblocks - XFS_ALLOC_SET_ASIDE(mp);
 525                 delta = request - mp->m_resblks;
 526                 lcounter = free - delta;
 527                 if (lcounter < 0) {
 528                         /* We can't satisfy the request, just get what we can */
 529                         mp->m_resblks += free;
 530                         mp->m_resblks_avail += free;
 531                         mp->m_sb.sb_fdblocks = XFS_ALLOC_SET_ASIDE(mp);
 532                 } else {
 533                         mp->m_sb.sb_fdblocks =
 534                                 lcounter + XFS_ALLOC_SET_ASIDE(mp);
 535                         mp->m_resblks = request;
 536                         mp->m_resblks_avail += delta;
 537                 }
 538         }
 539
 540         outval->resblks = mp->m_resblks;
 541         outval->resblks_avail = mp->m_resblks_avail;
 542         XFS_SB_UNLOCK(mp, s);
 543         return 0;
 544 }
 545
 546 void
 547 xfs_fs_log_dummy(
 548         xfs_mount_t     *mp)
 549 {
 550         xfs_trans_t     *tp;
 551         xfs_inode_t     *ip;
 552
 553         tp = _xfs_trans_alloc(mp, XFS_TRANS_DUMMY1);
 554         if (xfs_trans_reserve(tp, 0, XFS_ICHANGE_LOG_RES(mp), 0, 0, 0)) {
 555                 xfs_trans_cancel(tp, 0);
 556                 return;
 557         }
 558
 559         ip = mp->m_rootip;
 560         xfs_ilock(ip, XFS_ILOCK_EXCL);
 561
 562         xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
 563         xfs_trans_ihold(tp, ip);
 564         xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
 565         xfs_trans_set_sync(tp);
 566         xfs_trans_commit(tp, 0, NULL);
 567
 568         xfs_iunlock(ip, XFS_ILOCK_EXCL);
 569 }
 570
 571 int
 572 xfs_fs_goingdown(
 573         xfs_mount_t     *mp,
 574         __uint32_t      inflags)
 575 {
 576         switch (inflags) {
 577         case XFS_FSOP_GOING_FLAGS_DEFAULT: {
 578                 struct bhv_vfs *vfsp = XFS_MTOVFS(mp);
 579                 struct super_block *sb = freeze_bdev(vfsp->vfs_super->s_bdev);
 580
 581                 if (sb && !IS_ERR(sb)) {
 582                         xfs_force_shutdown(mp, SHUTDOWN_FORCE_UMOUNT);
 583                         thaw_bdev(sb->s_bdev, sb);
 584                 }
 585
 586                 break;
 587         }
 588         case XFS_FSOP_GOING_FLAGS_LOGFLUSH:
 589                 xfs_force_shutdown(mp, SHUTDOWN_FORCE_UMOUNT);
 590                 break;
 591         case XFS_FSOP_GOING_FLAGS_NOLOGFLUSH:
 592                 xfs_force_shutdown(mp,
 593                                 SHUTDOWN_FORCE_UMOUNT | SHUTDOWN_LOG_IO_ERROR);
 594                 break;
 595         default:
 596                 return XFS_ERROR(EINVAL);
 597         }
 598
 599         return 0;
 600 }