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

   1 /*
   2  * Copyright (c) 2000-2004 Silicon Graphics, Inc.  All Rights Reserved.
   3  *
   4  * This program is free software; you can redistribute it and/or modify it
   5  * under the terms of version 2 of the GNU General Public License as
   6  * published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it would be useful, but
   9  * WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  11  *
  12  * Further, this software is distributed without any warranty that it is
  13  * free of the rightful claim of any third person regarding infringement
  14  * or the like.  Any license provided herein, whether implied or
  15  * otherwise, applies only to this software file.  Patent licenses, if
  16  * any, provided herein do not apply to combinations of this program with
  17  * other software, or any other product whatsoever.
  18  *
  19  * You should have received a copy of the GNU General Public License along
  20  * with this program; if not, write the Free Software Foundation, Inc., 59
  21  * Temple Place - Suite 330, Boston MA 02111-1307, USA.
  22  *
  23  * Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy,
  24  * Mountain View, CA  94043, or:
  25  *
  26  * http://www.sgi.com
  27  *
  28  * For further information regarding this notice, see:
  29  *
  30  * http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/
  31  */
  32
  33 #include "xfs.h"
  34
  35 #include "xfs_fs.h"
  36 #include "xfs_inum.h"
  37 #include "xfs_log.h"
  38 #include "xfs_trans.h"
  39 #include "xfs_sb.h"
  40 #include "xfs_ag.h"
  41 #include "xfs_dir.h"
  42 #include "xfs_dir2.h"
  43 #include "xfs_alloc.h"
  44 #include "xfs_dmapi.h"
  45 #include "xfs_quota.h"
  46 #include "xfs_mount.h"
  47 #include "xfs_alloc_btree.h"
  48 #include "xfs_bmap_btree.h"
  49 #include "xfs_ialloc_btree.h"
  50 #include "xfs_btree.h"
  51 #include "xfs_ialloc.h"
  52 #include "xfs_attr_sf.h"
  53 #include "xfs_dir_sf.h"
  54 #include "xfs_dir2_sf.h"
  55 #include "xfs_dinode.h"
  56 #include "xfs_inode.h"
  57 #include "xfs_bmap.h"
  58 #include "xfs_bit.h"
  59 #include "xfs_rtalloc.h"
  60 #include "xfs_error.h"
  61 #include "xfs_itable.h"
  62 #include "xfs_rw.h"
  63 #include "xfs_acl.h"
  64 #include "xfs_cap.h"
  65 #include "xfs_mac.h"
  66 #include "xfs_attr.h"
  67 #include "xfs_buf_item.h"
  68 #include "xfs_trans_space.h"
  69 #include "xfs_utils.h"
  70 #include "xfs_iomap.h"
  71
  72 #if defined(XFS_RW_TRACE)
  73 void
  74 xfs_iomap_enter_trace(
  75         int             tag,
  76         xfs_iocore_t    *io,
  77         xfs_off_t       offset,
  78         ssize_t         count)
  79 {
  80         xfs_inode_t     *ip = XFS_IO_INODE(io);
  81
  82         if (!ip->i_rwtrace)
  83                 return;
  84
  85         ktrace_enter(ip->i_rwtrace,
  86                 (void *)((unsigned long)tag),
  87                 (void *)ip,
  88                 (void *)((unsigned long)((ip->i_d.di_size >> 32) & 0xffffffff)),
  89                 (void *)((unsigned long)(ip->i_d.di_size & 0xffffffff)),
  90                 (void *)((unsigned long)((offset >> 32) & 0xffffffff)),
  91                 (void *)((unsigned long)(offset & 0xffffffff)),
  92                 (void *)((unsigned long)count),
  93                 (void *)((unsigned long)((io->io_new_size >> 32) & 0xffffffff)),
  94                 (void *)((unsigned long)(io->io_new_size & 0xffffffff)),
  95                 (void *)NULL,
  96                 (void *)NULL,
  97                 (void *)NULL,
  98                 (void *)NULL,
  99                 (void *)NULL,
 100                 (void *)NULL,
 101                 (void *)NULL);
 102 }
 103
 104 void
 105 xfs_iomap_map_trace(
 106         int             tag,
 107         xfs_iocore_t    *io,
 108         xfs_off_t       offset,
 109         ssize_t         count,
 110         xfs_iomap_t     *iomapp,
 111         xfs_bmbt_irec_t *imapp,
 112         int             flags)
 113 {
 114         xfs_inode_t     *ip = XFS_IO_INODE(io);
 115
 116         if (!ip->i_rwtrace)
 117                 return;
 118
 119         ktrace_enter(ip->i_rwtrace,
 120                 (void *)((unsigned long)tag),
 121                 (void *)ip,
 122                 (void *)((unsigned long)((ip->i_d.di_size >> 32) & 0xffffffff)),
 123                 (void *)((unsigned long)(ip->i_d.di_size & 0xffffffff)),
 124                 (void *)((unsigned long)((offset >> 32) & 0xffffffff)),
 125                 (void *)((unsigned long)(offset & 0xffffffff)),
 126                 (void *)((unsigned long)count),
 127                 (void *)((unsigned long)flags),
 128                 (void *)((unsigned long)((iomapp->iomap_offset >> 32) & 0xffffffff)),
 129                 (void *)((unsigned long)(iomapp->iomap_offset & 0xffffffff)),
 130                 (void *)((unsigned long)(iomapp->iomap_delta)),
 131                 (void *)((unsigned long)(iomapp->iomap_bsize)),
 132                 (void *)((unsigned long)(iomapp->iomap_bn)),
 133                 (void *)(__psint_t)(imapp->br_startoff),
 134                 (void *)((unsigned long)(imapp->br_blockcount)),
 135                 (void *)(__psint_t)(imapp->br_startblock));
 136 }
 137 #else
 138 #define xfs_iomap_enter_trace(tag, io, offset, count)
 139 #define xfs_iomap_map_trace(tag, io, offset, count, iomapp, imapp, flags)
 140 #endif
 141
 142 #define XFS_WRITEIO_ALIGN(mp,off)       (((off) >> mp->m_writeio_log) \
 143                                                 << mp->m_writeio_log)
 144 #define XFS_STRAT_WRITE_IMAPS   2
 145 #define XFS_WRITE_IMAPS         XFS_BMAP_MAX_NMAP
 146
 147 STATIC int
 148 xfs_imap_to_bmap(
 149         xfs_iocore_t    *io,
 150         xfs_off_t       offset,
 151         xfs_bmbt_irec_t *imap,
 152         xfs_iomap_t     *iomapp,
 153         int             imaps,                  /* Number of imap entries */
 154         int             iomaps,                 /* Number of iomap entries */
 155         int             flags)
 156 {
 157         xfs_mount_t     *mp;
 158         xfs_fsize_t     nisize;
 159         int             pbm;
 160         xfs_fsblock_t   start_block;
 161
 162         mp = io->io_mount;
 163         nisize = XFS_SIZE(mp, io);
 164         if (io->io_new_size > nisize)
 165                 nisize = io->io_new_size;
 166
 167         for (pbm = 0; imaps && pbm < iomaps; imaps--, iomapp++, imap++, pbm++) {
 168                 iomapp->iomap_offset = XFS_FSB_TO_B(mp, imap->br_startoff);
 169                 iomapp->iomap_delta = offset - iomapp->iomap_offset;
 170                 iomapp->iomap_bsize = XFS_FSB_TO_B(mp, imap->br_blockcount);
 171                 iomapp->iomap_flags = flags;
 172
 173                 if (io->io_flags & XFS_IOCORE_RT) {
 174                         iomapp->iomap_flags |= IOMAP_REALTIME;
 175                         iomapp->iomap_target = mp->m_rtdev_targp;
 176                 } else {
 177                         iomapp->iomap_target = mp->m_ddev_targp;
 178                 }
 179                 start_block = imap->br_startblock;
 180                 if (start_block == HOLESTARTBLOCK) {
 181                         iomapp->iomap_bn = IOMAP_DADDR_NULL;
 182                         iomapp->iomap_flags |= IOMAP_HOLE;
 183                 } else if (start_block == DELAYSTARTBLOCK) {
 184                         iomapp->iomap_bn = IOMAP_DADDR_NULL;
 185                         iomapp->iomap_flags |= IOMAP_DELAY;
 186                 } else {
 187                         iomapp->iomap_bn = XFS_FSB_TO_DB_IO(io, start_block);
 188                         if (ISUNWRITTEN(imap))
 189                                 iomapp->iomap_flags |= IOMAP_UNWRITTEN;
 190                 }
 191
 192                 if ((iomapp->iomap_offset + iomapp->iomap_bsize) >= nisize) {
 193                         iomapp->iomap_flags |= IOMAP_EOF;
 194                 }
 195
 196                 offset += iomapp->iomap_bsize - iomapp->iomap_delta;
 197         }
 198         return pbm;     /* Return the number filled */
 199 }
 200
 201 int
 202 xfs_iomap(
 203         xfs_iocore_t    *io,
 204         xfs_off_t       offset,
 205         ssize_t         count,
 206         int             flags,
 207         xfs_iomap_t     *iomapp,
 208         int             *niomaps)
 209 {
 210         xfs_mount_t     *mp = io->io_mount;
 211         xfs_fileoff_t   offset_fsb, end_fsb;
 212         int             error = 0;
 213         int             lockmode = 0;
 214         xfs_bmbt_irec_t imap;
 215         int             nimaps = 1;
 216         int             bmapi_flags = 0;
 217         int             iomap_flags = 0;
 218
 219         if (XFS_FORCED_SHUTDOWN(mp))
 220                 return XFS_ERROR(EIO);
 221
 222         switch (flags &
 223                 (BMAPI_READ | BMAPI_WRITE | BMAPI_ALLOCATE |
 224                  BMAPI_UNWRITTEN | BMAPI_DEVICE)) {
 225         case BMAPI_READ:
 226                 xfs_iomap_enter_trace(XFS_IOMAP_READ_ENTER, io, offset, count);
 227                 lockmode = XFS_LCK_MAP_SHARED(mp, io);
 228                 bmapi_flags = XFS_BMAPI_ENTIRE;
 229                 if (flags & BMAPI_IGNSTATE)
 230                         bmapi_flags |= XFS_BMAPI_IGSTATE;
 231                 break;
 232         case BMAPI_WRITE:
 233                 xfs_iomap_enter_trace(XFS_IOMAP_WRITE_ENTER, io, offset, count);
 234                 lockmode = XFS_ILOCK_EXCL|XFS_EXTSIZE_WR;
 235                 bmapi_flags = 0;
 236                 XFS_ILOCK(mp, io, lockmode);
 237                 break;
 238         case BMAPI_ALLOCATE:
 239                 xfs_iomap_enter_trace(XFS_IOMAP_ALLOC_ENTER, io, offset, count);
 240                 lockmode = XFS_ILOCK_SHARED|XFS_EXTSIZE_RD;
 241                 bmapi_flags = XFS_BMAPI_ENTIRE;
 242                 /* Attempt non-blocking lock */
 243                 if (flags & BMAPI_TRYLOCK) {
 244                         if (!XFS_ILOCK_NOWAIT(mp, io, lockmode))
 245                                 return XFS_ERROR(EAGAIN);
 246                 } else {
 247                         XFS_ILOCK(mp, io, lockmode);
 248                 }
 249                 break;
 250         case BMAPI_UNWRITTEN:
 251                 goto phase2;
 252         case BMAPI_DEVICE:
 253                 lockmode = XFS_LCK_MAP_SHARED(mp, io);
 254                 iomapp->iomap_target = io->io_flags & XFS_IOCORE_RT ?
 255                         mp->m_rtdev_targp : mp->m_ddev_targp;
 256                 error = 0;
 257                 *niomaps = 1;
 258                 goto out;
 259         default:
 260                 BUG();
 261         }
 262
 263         ASSERT(offset <= mp->m_maxioffset);
 264         if ((xfs_fsize_t)offset + count > mp->m_maxioffset)
 265                 count = mp->m_maxioffset - offset;
 266         end_fsb = XFS_B_TO_FSB(mp, (xfs_ufsize_t)offset + count);
 267         offset_fsb = XFS_B_TO_FSBT(mp, offset);
 268
 269         error = XFS_BMAPI(mp, NULL, io, offset_fsb,
 270                         (xfs_filblks_t)(end_fsb - offset_fsb),
 271                         bmapi_flags,  NULL, 0, &imap,
 272                         &nimaps, NULL);
 273
 274         if (error)
 275                 goto out;
 276
 277 phase2:
 278         switch (flags & (BMAPI_WRITE|BMAPI_ALLOCATE|BMAPI_UNWRITTEN)) {
 279         case BMAPI_WRITE:
 280                 /* If we found an extent, return it */
 281                 if (nimaps &&
 282                     (imap.br_startblock != HOLESTARTBLOCK) &&
 283                     (imap.br_startblock != DELAYSTARTBLOCK)) {
 284                         xfs_iomap_map_trace(XFS_IOMAP_WRITE_MAP, io,
 285                                         offset, count, iomapp, &imap, flags);
 286                         break;
 287                 }
 288
 289                 if (flags & (BMAPI_DIRECT|BMAPI_MMAP)) {
 290                         error = XFS_IOMAP_WRITE_DIRECT(mp, io, offset,
 291                                         count, flags, &imap, &nimaps, nimaps);
 292                 } else {
 293                         error = XFS_IOMAP_WRITE_DELAY(mp, io, offset, count,
 294                                         flags, &imap, &nimaps);
 295                 }
 296                 if (!error) {
 297                         xfs_iomap_map_trace(XFS_IOMAP_ALLOC_MAP, io,
 298                                         offset, count, iomapp, &imap, flags);
 299                 }
 300                 iomap_flags = IOMAP_NEW;
 301                 break;
 302         case BMAPI_ALLOCATE:
 303                 /* If we found an extent, return it */
 304                 XFS_IUNLOCK(mp, io, lockmode);
 305                 lockmode = 0;
 306
 307                 if (nimaps && !ISNULLSTARTBLOCK(imap.br_startblock)) {
 308                         xfs_iomap_map_trace(XFS_IOMAP_WRITE_MAP, io,
 309                                         offset, count, iomapp, &imap, flags);
 310                         break;
 311                 }
 312
 313                 error = XFS_IOMAP_WRITE_ALLOCATE(mp, io, offset, count,
 314                                                  &imap, &nimaps);
 315                 break;
 316         case BMAPI_UNWRITTEN:
 317                 lockmode = 0;
 318                 error = XFS_IOMAP_WRITE_UNWRITTEN(mp, io, offset, count);
 319                 nimaps = 0;
 320                 break;
 321         }
 322
 323         if (nimaps) {
 324                 *niomaps = xfs_imap_to_bmap(io, offset, &imap,
 325                                             iomapp, nimaps, *niomaps, iomap_flags);
 326         } else if (niomaps) {
 327                 *niomaps = 0;
 328         }
 329
 330 out:
 331         if (lockmode)
 332                 XFS_IUNLOCK(mp, io, lockmode);
 333         return XFS_ERROR(error);
 334 }
 335
 336 STATIC int
 337 xfs_flush_space(
 338         xfs_inode_t     *ip,
 339         int             *fsynced,
 340         int             *ioflags)
 341 {
 342         switch (*fsynced) {
 343         case 0:
 344                 if (ip->i_delayed_blks) {
 345                         xfs_iunlock(ip, XFS_ILOCK_EXCL);
 346                         xfs_flush_inode(ip);
 347                         xfs_ilock(ip, XFS_ILOCK_EXCL);
 348                         *fsynced = 1;
 349                 } else {
 350                         *ioflags |= BMAPI_SYNC;
 351                         *fsynced = 2;
 352                 }
 353                 return 0;
 354         case 1:
 355                 *fsynced = 2;
 356                 *ioflags |= BMAPI_SYNC;
 357                 return 0;
 358         case 2:
 359                 xfs_iunlock(ip, XFS_ILOCK_EXCL);
 360                 xfs_flush_device(ip);
 361                 xfs_ilock(ip, XFS_ILOCK_EXCL);
 362                 *fsynced = 3;
 363                 return 0;
 364         }
 365         return 1;
 366 }
 367
 368 int
 369 xfs_iomap_write_direct(
 370         xfs_inode_t     *ip,
 371         xfs_off_t       offset,
 372         size_t          count,
 373         int             flags,
 374         xfs_bmbt_irec_t *ret_imap,
 375         int             *nmaps,
 376         int             found)
 377 {
 378         xfs_mount_t     *mp = ip->i_mount;
 379         xfs_iocore_t    *io = &ip->i_iocore;
 380         xfs_fileoff_t   offset_fsb;
 381         xfs_fileoff_t   last_fsb;
 382         xfs_filblks_t   count_fsb;
 383         xfs_fsize_t     isize;
 384         xfs_fsblock_t   firstfsb;
 385         int             nimaps, maps;
 386         int             error;
 387         int             bmapi_flag;
 388         int             rt;
 389         xfs_trans_t     *tp;
 390         xfs_bmbt_irec_t imap[XFS_WRITE_IMAPS], *imapp;
 391         xfs_bmap_free_t free_list;
 392         int             aeof;
 393         xfs_filblks_t   datablocks;
 394         int             committed;
 395         int             numrtextents;
 396         uint            resblks;
 397
 398         /*
 399          * Make sure that the dquots are there. This doesn't hold
 400          * the ilock across a disk read.
 401          */
 402         error = XFS_QM_DQATTACH(ip->i_mount, ip, XFS_QMOPT_ILOCKED);
 403         if (error)
 404                 return XFS_ERROR(error);
 405
 406         maps = min(XFS_WRITE_IMAPS, *nmaps);
 407         nimaps = maps;
 408
 409         isize = ip->i_d.di_size;
 410         aeof = (offset + count) > isize;
 411
 412         if (io->io_new_size > isize)
 413                 isize = io->io_new_size;
 414
 415         offset_fsb = XFS_B_TO_FSBT(mp, offset);
 416         last_fsb = XFS_B_TO_FSB(mp, ((xfs_ufsize_t)(offset + count)));
 417         count_fsb = last_fsb - offset_fsb;
 418         if (found && (ret_imap->br_startblock == HOLESTARTBLOCK)) {
 419                 xfs_fileoff_t   map_last_fsb;
 420
 421                 map_last_fsb = ret_imap->br_blockcount + ret_imap->br_startoff;
 422
 423                 if (map_last_fsb < last_fsb) {
 424                         last_fsb = map_last_fsb;
 425                         count_fsb = last_fsb - offset_fsb;
 426                 }
 427                 ASSERT(count_fsb > 0);
 428         }
 429
 430         /*
 431          * determine if reserving space on
 432          * the data or realtime partition.
 433          */
 434         if ((rt = XFS_IS_REALTIME_INODE(ip))) {
 435                 int     sbrtextsize, iprtextsize;
 436
 437                 sbrtextsize = mp->m_sb.sb_rextsize;
 438                 iprtextsize =
 439                         ip->i_d.di_extsize ? ip->i_d.di_extsize : sbrtextsize;
 440                 numrtextents = (count_fsb + iprtextsize - 1);
 441                 do_div(numrtextents, sbrtextsize);
 442                 datablocks = 0;
 443         } else {
 444                 datablocks = count_fsb;
 445                 numrtextents = 0;
 446         }
 447
 448         /*
 449          * allocate and setup the transaction
 450          */
 451         xfs_iunlock(ip, XFS_ILOCK_EXCL);
 452         tp = xfs_trans_alloc(mp, XFS_TRANS_DIOSTRAT);
 453
 454         resblks = XFS_DIOSTRAT_SPACE_RES(mp, datablocks);
 455
 456         error = xfs_trans_reserve(tp, resblks,
 457                         XFS_WRITE_LOG_RES(mp), numrtextents,
 458                         XFS_TRANS_PERM_LOG_RES,
 459                         XFS_WRITE_LOG_COUNT);
 460
 461         /*
 462          * check for running out of space
 463          */
 464         if (error)
 465                 /*
 466                  * Free the transaction structure.
 467                  */
 468                 xfs_trans_cancel(tp, 0);
 469
 470         xfs_ilock(ip, XFS_ILOCK_EXCL);
 471
 472         if (error)
 473                 goto error_out; /* Don't return in above if .. trans ..,
 474                                         need lock to return */
 475
 476         if (XFS_TRANS_RESERVE_BLKQUOTA(mp, tp, ip, resblks)) {
 477                 error = (EDQUOT);
 478                 goto error1;
 479         }
 480         nimaps = 1;
 481
 482         bmapi_flag = XFS_BMAPI_WRITE;
 483         xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
 484         xfs_trans_ihold(tp, ip);
 485
 486         if (!(flags & BMAPI_MMAP) && (offset < ip->i_d.di_size || rt))
 487                 bmapi_flag |= XFS_BMAPI_PREALLOC;
 488
 489         /*
 490          * issue the bmapi() call to allocate the blocks
 491          */
 492         XFS_BMAP_INIT(&free_list, &firstfsb);
 493         imapp = &imap[0];
 494         error = xfs_bmapi(tp, ip, offset_fsb, count_fsb,
 495                 bmapi_flag, &firstfsb, 0, imapp, &nimaps, &free_list);
 496         if (error) {
 497                 goto error0;
 498         }
 499
 500         /*
 501          * complete the transaction
 502          */
 503
 504         error = xfs_bmap_finish(&tp, &free_list, firstfsb, &committed);
 505         if (error) {
 506                 goto error0;
 507         }
 508
 509         error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES, NULL);
 510         if (error) {
 511                 goto error_out;
 512         }
 513
 514         /* copy any maps to caller's array and return any error. */
 515         if (nimaps == 0) {
 516                 error = (ENOSPC);
 517                 goto error_out;
 518         }
 519
 520         *ret_imap = imap[0];
 521         *nmaps = 1;
 522         if ( !(io->io_flags & XFS_IOCORE_RT)  && !ret_imap->br_startblock) {
 523                 cmn_err(CE_PANIC,"Access to block zero:  fs <%s> inode: %lld "
 524                         "start_block : %llx start_off : %llx blkcnt : %llx "
 525                         "extent-state : %x \n",
 526                         (ip->i_mount)->m_fsname,
 527                         (long long)ip->i_ino,
 528                         ret_imap->br_startblock, ret_imap->br_startoff,
 529                         ret_imap->br_blockcount,ret_imap->br_state);
 530         }
 531         return 0;
 532
 533  error0:        /* Cancel bmap, unlock inode, and cancel trans */
 534         xfs_bmap_cancel(&free_list);
 535
 536  error1:        /* Just cancel transaction */
 537         xfs_trans_cancel(tp, XFS_TRANS_RELEASE_LOG_RES | XFS_TRANS_ABORT);
 538         *nmaps = 0;     /* nothing set-up here */
 539
 540 error_out:
 541         return XFS_ERROR(error);
 542 }
 543
 544 int
 545 xfs_iomap_write_delay(
 546         xfs_inode_t     *ip,
 547         xfs_off_t       offset,
 548         size_t          count,
 549         int             ioflag,
 550         xfs_bmbt_irec_t *ret_imap,
 551         int             *nmaps)
 552 {
 553         xfs_mount_t     *mp = ip->i_mount;
 554         xfs_iocore_t    *io = &ip->i_iocore;
 555         xfs_fileoff_t   offset_fsb;
 556         xfs_fileoff_t   last_fsb;
 557         xfs_fsize_t     isize;
 558         xfs_fsblock_t   firstblock;
 559         int             nimaps;
 560         int             error;
 561         xfs_bmbt_irec_t imap[XFS_WRITE_IMAPS];
 562         int             aeof;
 563         int             fsynced = 0;
 564
 565         ASSERT(ismrlocked(&ip->i_lock, MR_UPDATE) != 0);
 566
 567         /*
 568          * Make sure that the dquots are there. This doesn't hold
 569          * the ilock across a disk read.
 570          */
 571
 572         error = XFS_QM_DQATTACH(mp, ip, XFS_QMOPT_ILOCKED);
 573         if (error)
 574                 return XFS_ERROR(error);
 575
 576 retry:
 577         isize = ip->i_d.di_size;
 578         if (io->io_new_size > isize) {
 579                 isize = io->io_new_size;
 580         }
 581
 582         aeof = 0;
 583         offset_fsb = XFS_B_TO_FSBT(mp, offset);
 584         last_fsb = XFS_B_TO_FSB(mp, ((xfs_ufsize_t)(offset + count)));
 585         /*
 586          * If the caller is doing a write at the end of the file,
 587          * then extend the allocation (and the buffer used for the write)
 588          * out to the file system's write iosize.  We clean up any extra
 589          * space left over when the file is closed in xfs_inactive().
 590          *
 591          * For sync writes, we are flushing delayed allocate space to
 592          * try to make additional space available for allocation near
 593          * the filesystem full boundary - preallocation hurts in that
 594          * situation, of course.
 595          */
 596         if (!(ioflag & BMAPI_SYNC) && ((offset + count) > ip->i_d.di_size)) {
 597                 xfs_off_t       aligned_offset;
 598                 xfs_filblks_t   count_fsb;
 599                 unsigned int    iosize;
 600                 xfs_fileoff_t   ioalign;
 601                 int             n;
 602                 xfs_fileoff_t   start_fsb;
 603
 604                 /*
 605                  * If there are any real blocks past eof, then don't
 606                  * do any speculative allocation.
 607                  */
 608                 start_fsb = XFS_B_TO_FSBT(mp,
 609                                         ((xfs_ufsize_t)(offset + count - 1)));
 610                 count_fsb = XFS_B_TO_FSB(mp, (xfs_ufsize_t)XFS_MAXIOFFSET(mp));
 611                 while (count_fsb > 0) {
 612                         nimaps = XFS_WRITE_IMAPS;
 613                         error = XFS_BMAPI(mp, NULL, io, start_fsb, count_fsb,
 614                                         0, &firstblock, 0, imap, &nimaps, NULL);
 615                         if (error) {
 616                                 return error;
 617                         }
 618                         for (n = 0; n < nimaps; n++) {
 619                                 if ( !(io->io_flags & XFS_IOCORE_RT)  &&
 620                                         !imap[n].br_startblock) {
 621                                         cmn_err(CE_PANIC,"Access to block "
 622                                                 "zero:  fs <%s> inode: %lld "
 623                                                 "start_block : %llx start_off "
 624                                                 ": %llx blkcnt : %llx "
 625                                                 "extent-state : %x \n",
 626                                                 (ip->i_mount)->m_fsname,
 627                                                 (long long)ip->i_ino,
 628                                                 imap[n].br_startblock,
 629                                                 imap[n].br_startoff,
 630                                                 imap[n].br_blockcount,
 631                                                 imap[n].br_state);
 632                                 }
 633                                 if ((imap[n].br_startblock != HOLESTARTBLOCK) &&
 634                                     (imap[n].br_startblock != DELAYSTARTBLOCK)) {
 635                                         goto write_map;
 636                                 }
 637                                 start_fsb += imap[n].br_blockcount;
 638                                 count_fsb -= imap[n].br_blockcount;
 639                         }
 640                 }
 641                 iosize = mp->m_writeio_blocks;
 642                 aligned_offset = XFS_WRITEIO_ALIGN(mp, (offset + count - 1));
 643                 ioalign = XFS_B_TO_FSBT(mp, aligned_offset);
 644                 last_fsb = ioalign + iosize;
 645                 aeof = 1;
 646         }
 647 write_map:
 648         nimaps = XFS_WRITE_IMAPS;
 649         firstblock = NULLFSBLOCK;
 650
 651         /*
 652          * If mounted with the "-o swalloc" option, roundup the allocation
 653          * request to a stripe width boundary if the file size is >=
 654          * stripe width and we are allocating past the allocation eof.
 655          */
 656         if (!(io->io_flags & XFS_IOCORE_RT) && mp->m_swidth
 657             && (mp->m_flags & XFS_MOUNT_SWALLOC)
 658             && (isize >= XFS_FSB_TO_B(mp, mp->m_swidth)) && aeof) {
 659                 int eof;
 660                 xfs_fileoff_t new_last_fsb;
 661
 662                 new_last_fsb = roundup_64(last_fsb, mp->m_swidth);
 663                 error = xfs_bmap_eof(ip, new_last_fsb, XFS_DATA_FORK, &eof);
 664                 if (error) {
 665                         return error;
 666                 }
 667                 if (eof) {
 668                         last_fsb = new_last_fsb;
 669                 }
 670         /*
 671          * Roundup the allocation request to a stripe unit (m_dalign) boundary
 672          * if the file size is >= stripe unit size, and we are allocating past
 673          * the allocation eof.
 674          */
 675         } else if (!(io->io_flags & XFS_IOCORE_RT) && mp->m_dalign &&
 676                    (isize >= XFS_FSB_TO_B(mp, mp->m_dalign)) && aeof) {
 677                 int eof;
 678                 xfs_fileoff_t new_last_fsb;
 679                 new_last_fsb = roundup_64(last_fsb, mp->m_dalign);
 680                 error = xfs_bmap_eof(ip, new_last_fsb, XFS_DATA_FORK, &eof);
 681                 if (error) {
 682                         return error;
 683                 }
 684                 if (eof) {
 685                         last_fsb = new_last_fsb;
 686                 }
 687         /*
 688          * Round up the allocation request to a real-time extent boundary
 689          * if the file is on the real-time subvolume.
 690          */
 691         } else if (io->io_flags & XFS_IOCORE_RT && aeof) {
 692                 int eof;
 693                 xfs_fileoff_t new_last_fsb;
 694
 695                 new_last_fsb = roundup_64(last_fsb, mp->m_sb.sb_rextsize);
 696                 error = XFS_BMAP_EOF(mp, io, new_last_fsb, XFS_DATA_FORK, &eof);
 697                 if (error) {
 698                         return error;
 699                 }
 700                 if (eof)
 701                         last_fsb = new_last_fsb;
 702         }
 703         error = xfs_bmapi(NULL, ip, offset_fsb,
 704                           (xfs_filblks_t)(last_fsb - offset_fsb),
 705                           XFS_BMAPI_DELAY | XFS_BMAPI_WRITE |
 706                           XFS_BMAPI_ENTIRE, &firstblock, 1, imap,
 707                           &nimaps, NULL);
 708         /*
 709          * This can be EDQUOT, if nimaps == 0
 710          */
 711         if (error && (error != ENOSPC)) {
 712                 return XFS_ERROR(error);
 713         }
 714         /*
 715          * If bmapi returned us nothing, and if we didn't get back EDQUOT,
 716          * then we must have run out of space.
 717          */
 718         if (nimaps == 0) {
 719                 xfs_iomap_enter_trace(XFS_IOMAP_WRITE_NOSPACE,
 720                                         io, offset, count);
 721                 if (xfs_flush_space(ip, &fsynced, &ioflag))
 722                         return XFS_ERROR(ENOSPC);
 723
 724                 error = 0;
 725                 goto retry;
 726         }
 727
 728         *ret_imap = imap[0];
 729         *nmaps = 1;
 730         if ( !(io->io_flags & XFS_IOCORE_RT)  && !ret_imap->br_startblock) {
 731                 cmn_err(CE_PANIC,"Access to block zero:  fs <%s> inode: %lld "
 732                         "start_block : %llx start_off : %llx blkcnt : %llx "
 733                         "extent-state : %x \n",
 734                         (ip->i_mount)->m_fsname,
 735                         (long long)ip->i_ino,
 736                         ret_imap->br_startblock, ret_imap->br_startoff,
 737                         ret_imap->br_blockcount,ret_imap->br_state);
 738         }
 739         return 0;
 740 }
 741
 742 /*
 743  * Pass in a delayed allocate extent, convert it to real extents;
 744  * return to the caller the extent we create which maps on top of
 745  * the originating callers request.
 746  *
 747  * Called without a lock on the inode.
 748  */
 749 int
 750 xfs_iomap_write_allocate(
 751         xfs_inode_t     *ip,
 752         xfs_off_t       offset,
 753         size_t          count,
 754         xfs_bmbt_irec_t *map,
 755         int             *retmap)
 756 {
 757         xfs_mount_t     *mp = ip->i_mount;
 758         xfs_iocore_t    *io = &ip->i_iocore;
 759         xfs_fileoff_t   offset_fsb, last_block;
 760         xfs_fileoff_t   end_fsb, map_start_fsb;
 761         xfs_fsblock_t   first_block;
 762         xfs_bmap_free_t free_list;
 763         xfs_filblks_t   count_fsb;
 764         xfs_bmbt_irec_t imap[XFS_STRAT_WRITE_IMAPS];
 765         xfs_trans_t     *tp;
 766         int             i, nimaps, committed;
 767         int             error = 0;
 768         int             nres;
 769
 770         *retmap = 0;
 771
 772         /*
 773          * Make sure that the dquots are there.
 774          */
 775         if ((error = XFS_QM_DQATTACH(mp, ip, 0)))
 776                 return XFS_ERROR(error);
 777
 778         offset_fsb = XFS_B_TO_FSBT(mp, offset);
 779         count_fsb = map->br_blockcount;
 780         map_start_fsb = map->br_startoff;
 781
 782         XFS_STATS_ADD(xs_xstrat_bytes, XFS_FSB_TO_B(mp, count_fsb));
 783
 784         while (count_fsb != 0) {
 785                 /*
 786                  * Set up a transaction with which to allocate the
 787                  * backing store for the file.  Do allocations in a
 788                  * loop until we get some space in the range we are
 789                  * interested in.  The other space that might be allocated
 790                  * is in the delayed allocation extent on which we sit
 791                  * but before our buffer starts.
 792                  */
 793
 794                 nimaps = 0;
 795                 while (nimaps == 0) {
 796                         tp = xfs_trans_alloc(mp, XFS_TRANS_STRAT_WRITE);
 797                         nres = XFS_EXTENTADD_SPACE_RES(mp, XFS_DATA_FORK);
 798                         error = xfs_trans_reserve(tp, nres,
 799                                         XFS_WRITE_LOG_RES(mp),
 800                                         0, XFS_TRANS_PERM_LOG_RES,
 801                                         XFS_WRITE_LOG_COUNT);
 802                         if (error == ENOSPC) {
 803                                 error = xfs_trans_reserve(tp, 0,
 804                                                 XFS_WRITE_LOG_RES(mp),
 805                                                 0,
 806                                                 XFS_TRANS_PERM_LOG_RES,
 807                                                 XFS_WRITE_LOG_COUNT);
 808                         }
 809                         if (error) {
 810                                 xfs_trans_cancel(tp, 0);
 811                                 return XFS_ERROR(error);
 812                         }
 813                         xfs_ilock(ip, XFS_ILOCK_EXCL);
 814                         xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
 815                         xfs_trans_ihold(tp, ip);
 816
 817                         XFS_BMAP_INIT(&free_list, &first_block);
 818
 819                         nimaps = XFS_STRAT_WRITE_IMAPS;
 820                         /*
 821                          * Ensure we don't go beyond eof - it is possible
 822                          * the extents changed since we did the read call,
 823                          * we dropped the ilock in the interim.
 824                          */
 825
 826                         end_fsb = XFS_B_TO_FSB(mp, ip->i_d.di_size);
 827                         xfs_bmap_last_offset(NULL, ip, &last_block,
 828                                 XFS_DATA_FORK);
 829                         last_block = XFS_FILEOFF_MAX(last_block, end_fsb);
 830                         if ((map_start_fsb + count_fsb) > last_block) {
 831                                 count_fsb = last_block - map_start_fsb;
 832                                 if (count_fsb == 0) {
 833                                         error = EAGAIN;
 834                                         goto trans_cancel;
 835                                 }
 836                         }
 837
 838                         /* Go get the actual blocks */
 839                         error = xfs_bmapi(tp, ip, map_start_fsb, count_fsb,
 840                                         XFS_BMAPI_WRITE, &first_block, 1,
 841                                         imap, &nimaps, &free_list);
 842                         if (error)
 843                                 goto trans_cancel;
 844
 845                         error = xfs_bmap_finish(&tp, &free_list,
 846                                         first_block, &committed);
 847                         if (error)
 848                                 goto trans_cancel;
 849
 850                         error = xfs_trans_commit(tp,
 851                                         XFS_TRANS_RELEASE_LOG_RES, NULL);
 852                         if (error)
 853                                 goto error0;
 854
 855                         xfs_iunlock(ip, XFS_ILOCK_EXCL);
 856                 }
 857
 858                 /*
 859                  * See if we were able to allocate an extent that
 860                  * covers at least part of the callers request
 861                  */
 862
 863                 for (i = 0; i < nimaps; i++) {
 864                         if ( !(io->io_flags & XFS_IOCORE_RT)  &&
 865                                 !imap[i].br_startblock) {
 866                                 cmn_err(CE_PANIC,"Access to block zero:  "
 867                                         "fs <%s> inode: %lld "
 868                                         "start_block : %llx start_off : %llx "
 869                                         "blkcnt : %llx extent-state : %x \n",
 870                                         (ip->i_mount)->m_fsname,
 871                                         (long long)ip->i_ino,
 872                                         imap[i].br_startblock,
 873                                         imap[i].br_startoff,
 874                                         imap[i].br_blockcount,imap[i].br_state);
 875                         }
 876                         if ((offset_fsb >= imap[i].br_startoff) &&
 877                             (offset_fsb < (imap[i].br_startoff +
 878                                            imap[i].br_blockcount))) {
 879                                 *map = imap[i];
 880                                 *retmap = 1;
 881                                 XFS_STATS_INC(xs_xstrat_quick);
 882                                 return 0;
 883                         }
 884                         count_fsb -= imap[i].br_blockcount;
 885                 }
 886
 887                 /* So far we have not mapped the requested part of the
 888                  * file, just surrounding data, try again.
 889                  */
 890                 nimaps--;
 891                 map_start_fsb = imap[nimaps].br_startoff +
 892                                 imap[nimaps].br_blockcount;
 893         }
 894
 895 trans_cancel:
 896         xfs_bmap_cancel(&free_list);
 897         xfs_trans_cancel(tp, XFS_TRANS_RELEASE_LOG_RES | XFS_TRANS_ABORT);
 898 error0:
 899         xfs_iunlock(ip, XFS_ILOCK_EXCL);
 900         return XFS_ERROR(error);
 901 }
 902
 903 int
 904 xfs_iomap_write_unwritten(
 905         xfs_inode_t     *ip,
 906         xfs_off_t       offset,
 907         size_t          count)
 908 {
 909         xfs_mount_t     *mp = ip->i_mount;
 910         xfs_iocore_t    *io = &ip->i_iocore;
 911         xfs_trans_t     *tp;
 912         xfs_fileoff_t   offset_fsb;
 913         xfs_filblks_t   count_fsb;
 914         xfs_filblks_t   numblks_fsb;
 915         xfs_bmbt_irec_t imap;
 916         int             committed;
 917         int             error;
 918         int             nres;
 919         int             nimaps;
 920         xfs_fsblock_t   firstfsb;
 921         xfs_bmap_free_t free_list;
 922
 923         xfs_iomap_enter_trace(XFS_IOMAP_UNWRITTEN,
 924                                 &ip->i_iocore, offset, count);
 925
 926         offset_fsb = XFS_B_TO_FSBT(mp, offset);
 927         count_fsb = XFS_B_TO_FSB(mp, (xfs_ufsize_t)offset + count);
 928         count_fsb = (xfs_filblks_t)(count_fsb - offset_fsb);
 929
 930         do {
 931                 nres = XFS_DIOSTRAT_SPACE_RES(mp, 0);
 932
 933                 /*
 934                  * set up a transaction to convert the range of extents
 935                  * from unwritten to real. Do allocations in a loop until
 936                  * we have covered the range passed in.
 937                  */
 938
 939                 tp = xfs_trans_alloc(mp, XFS_TRANS_STRAT_WRITE);
 940                 error = xfs_trans_reserve(tp, nres,
 941                                 XFS_WRITE_LOG_RES(mp), 0,
 942                                 XFS_TRANS_PERM_LOG_RES,
 943                                 XFS_WRITE_LOG_COUNT);
 944                 if (error) {
 945                         xfs_trans_cancel(tp, 0);
 946                         goto error0;
 947                 }
 948
 949                 xfs_ilock(ip, XFS_ILOCK_EXCL);
 950                 xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
 951                 xfs_trans_ihold(tp, ip);
 952
 953                 /*
 954                  * Modify the unwritten extent state of the buffer.
 955                  */
 956                 XFS_BMAP_INIT(&free_list, &firstfsb);
 957                 nimaps = 1;
 958                 error = xfs_bmapi(tp, ip, offset_fsb, count_fsb,
 959                                   XFS_BMAPI_WRITE, &firstfsb,
 960                                   1, &imap, &nimaps, &free_list);
 961                 if (error)
 962                         goto error_on_bmapi_transaction;
 963
 964                 error = xfs_bmap_finish(&(tp), &(free_list),
 965                                 firstfsb, &committed);
 966                 if (error)
 967                         goto error_on_bmapi_transaction;
 968
 969                 error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES, NULL);
 970                 xfs_iunlock(ip, XFS_ILOCK_EXCL);
 971                 if (error)
 972                         goto error0;
 973
 974                 if ( !(io->io_flags & XFS_IOCORE_RT)  && !imap.br_startblock) {
 975                         cmn_err(CE_PANIC,"Access to block zero:  fs <%s> "
 976                                 "inode: %lld start_block : %llx start_off : "
 977                                 "%llx blkcnt : %llx extent-state : %x \n",
 978                                 (ip->i_mount)->m_fsname,
 979                                 (long long)ip->i_ino,
 980                                 imap.br_startblock,imap.br_startoff,
 981                                 imap.br_blockcount,imap.br_state);
 982                 }
 983
 984                 if ((numblks_fsb = imap.br_blockcount) == 0) {
 985                         /*
 986                          * The numblks_fsb value should always get
 987                          * smaller, otherwise the loop is stuck.
 988                          */
 989                         ASSERT(imap.br_blockcount);
 990                         break;
 991                 }
 992                 offset_fsb += numblks_fsb;
 993                 count_fsb -= numblks_fsb;
 994         } while (count_fsb > 0);
 995
 996         return 0;
 997
 998 error_on_bmapi_transaction:
 999         xfs_bmap_cancel(&free_list);
1000         xfs_trans_cancel(tp, (XFS_TRANS_RELEASE_LOG_RES | XFS_TRANS_ABORT));
1001         xfs_iunlock(ip, XFS_ILOCK_EXCL);
1002 error0:
1003         return XFS_ERROR(error);
1004 }