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

   1 /*
   2  * Copyright (c) 2000-2006 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_bit.h"
  21 #include "xfs_log.h"
  22 #include "xfs_inum.h"
  23 #include "xfs_trans.h"
  24 #include "xfs_sb.h"
  25 #include "xfs_ag.h"
  26 #include "xfs_dir2.h"
  27 #include "xfs_alloc.h"
  28 #include "xfs_dmapi.h"
  29 #include "xfs_quota.h"
  30 #include "xfs_mount.h"
  31 #include "xfs_bmap_btree.h"
  32 #include "xfs_alloc_btree.h"
  33 #include "xfs_ialloc_btree.h"
  34 #include "xfs_dir2_sf.h"
  35 #include "xfs_attr_sf.h"
  36 #include "xfs_dinode.h"
  37 #include "xfs_inode.h"
  38 #include "xfs_ialloc.h"
  39 #include "xfs_btree.h"
  40 #include "xfs_bmap.h"
  41 #include "xfs_rtalloc.h"
  42 #include "xfs_error.h"
  43 #include "xfs_itable.h"
  44 #include "xfs_rw.h"
  45 #include "xfs_acl.h"
  46 #include "xfs_cap.h"
  47 #include "xfs_mac.h"
  48 #include "xfs_attr.h"
  49 #include "xfs_buf_item.h"
  50 #include "xfs_trans_space.h"
  51 #include "xfs_utils.h"
  52 #include "xfs_iomap.h"
  53
  54 #if defined(XFS_RW_TRACE)
  55 void
  56 xfs_iomap_enter_trace(
  57         int             tag,
  58         xfs_iocore_t    *io,
  59         xfs_off_t       offset,
  60         ssize_t         count)
  61 {
  62         xfs_inode_t     *ip = XFS_IO_INODE(io);
  63
  64         if (!ip->i_rwtrace)
  65                 return;
  66
  67         ktrace_enter(ip->i_rwtrace,
  68                 (void *)((unsigned long)tag),
  69                 (void *)ip,
  70                 (void *)((unsigned long)((ip->i_d.di_size >> 32) & 0xffffffff)),
  71                 (void *)((unsigned long)(ip->i_d.di_size & 0xffffffff)),
  72                 (void *)((unsigned long)((offset >> 32) & 0xffffffff)),
  73                 (void *)((unsigned long)(offset & 0xffffffff)),
  74                 (void *)((unsigned long)count),
  75                 (void *)((unsigned long)((io->io_new_size >> 32) & 0xffffffff)),
  76                 (void *)((unsigned long)(io->io_new_size & 0xffffffff)),
  77                 (void *)((unsigned long)current_pid()),
  78                 (void *)NULL,
  79                 (void *)NULL,
  80                 (void *)NULL,
  81                 (void *)NULL,
  82                 (void *)NULL,
  83                 (void *)NULL);
  84 }
  85
  86 void
  87 xfs_iomap_map_trace(
  88         int             tag,
  89         xfs_iocore_t    *io,
  90         xfs_off_t       offset,
  91         ssize_t         count,
  92         xfs_iomap_t     *iomapp,
  93         xfs_bmbt_irec_t *imapp,
  94         int             flags)
  95 {
  96         xfs_inode_t     *ip = XFS_IO_INODE(io);
  97
  98         if (!ip->i_rwtrace)
  99                 return;
 100
 101         ktrace_enter(ip->i_rwtrace,
 102                 (void *)((unsigned long)tag),
 103                 (void *)ip,
 104                 (void *)((unsigned long)((ip->i_d.di_size >> 32) & 0xffffffff)),
 105                 (void *)((unsigned long)(ip->i_d.di_size & 0xffffffff)),
 106                 (void *)((unsigned long)((offset >> 32) & 0xffffffff)),
 107                 (void *)((unsigned long)(offset & 0xffffffff)),
 108                 (void *)((unsigned long)count),
 109                 (void *)((unsigned long)flags),
 110                 (void *)((unsigned long)((iomapp->iomap_offset >> 32) & 0xffffffff)),
 111                 (void *)((unsigned long)(iomapp->iomap_offset & 0xffffffff)),
 112                 (void *)((unsigned long)(iomapp->iomap_delta)),
 113                 (void *)((unsigned long)(iomapp->iomap_bsize)),
 114                 (void *)((unsigned long)(iomapp->iomap_bn)),
 115                 (void *)(__psint_t)(imapp->br_startoff),
 116                 (void *)((unsigned long)(imapp->br_blockcount)),
 117                 (void *)(__psint_t)(imapp->br_startblock));
 118 }
 119 #else
 120 #define xfs_iomap_enter_trace(tag, io, offset, count)
 121 #define xfs_iomap_map_trace(tag, io, offset, count, iomapp, imapp, flags)
 122 #endif
 123
 124 #define XFS_WRITEIO_ALIGN(mp,off)       (((off) >> mp->m_writeio_log) \
 125                                                 << mp->m_writeio_log)
 126 #define XFS_STRAT_WRITE_IMAPS   2
 127 #define XFS_WRITE_IMAPS         XFS_BMAP_MAX_NMAP
 128
 129 STATIC int
 130 xfs_imap_to_bmap(
 131         xfs_iocore_t    *io,
 132         xfs_off_t       offset,
 133         xfs_bmbt_irec_t *imap,
 134         xfs_iomap_t     *iomapp,
 135         int             imaps,                  /* Number of imap entries */
 136         int             iomaps,                 /* Number of iomap entries */
 137         int             flags)
 138 {
 139         xfs_mount_t     *mp;
 140         xfs_fsize_t     nisize;
 141         int             pbm;
 142         xfs_fsblock_t   start_block;
 143
 144         mp = io->io_mount;
 145         nisize = XFS_SIZE(mp, io);
 146         if (io->io_new_size > nisize)
 147                 nisize = io->io_new_size;
 148
 149         for (pbm = 0; imaps && pbm < iomaps; imaps--, iomapp++, imap++, pbm++) {
 150                 iomapp->iomap_offset = XFS_FSB_TO_B(mp, imap->br_startoff);
 151                 iomapp->iomap_delta = offset - iomapp->iomap_offset;
 152                 iomapp->iomap_bsize = XFS_FSB_TO_B(mp, imap->br_blockcount);
 153                 iomapp->iomap_flags = flags;
 154
 155                 if (io->io_flags & XFS_IOCORE_RT) {
 156                         iomapp->iomap_flags |= IOMAP_REALTIME;
 157                         iomapp->iomap_target = mp->m_rtdev_targp;
 158                 } else {
 159                         iomapp->iomap_target = mp->m_ddev_targp;
 160                 }
 161                 start_block = imap->br_startblock;
 162                 if (start_block == HOLESTARTBLOCK) {
 163                         iomapp->iomap_bn = IOMAP_DADDR_NULL;
 164                         iomapp->iomap_flags |= IOMAP_HOLE;
 165                 } else if (start_block == DELAYSTARTBLOCK) {
 166                         iomapp->iomap_bn = IOMAP_DADDR_NULL;
 167                         iomapp->iomap_flags |= IOMAP_DELAY;
 168                 } else {
 169                         iomapp->iomap_bn = XFS_FSB_TO_DB_IO(io, start_block);
 170                         if (ISUNWRITTEN(imap))
 171                                 iomapp->iomap_flags |= IOMAP_UNWRITTEN;
 172                 }
 173
 174                 if ((iomapp->iomap_offset + iomapp->iomap_bsize) >= nisize) {
 175                         iomapp->iomap_flags |= IOMAP_EOF;
 176                 }
 177
 178                 offset += iomapp->iomap_bsize - iomapp->iomap_delta;
 179         }
 180         return pbm;     /* Return the number filled */
 181 }
 182
 183 int
 184 xfs_iomap(
 185         xfs_iocore_t    *io,
 186         xfs_off_t       offset,
 187         ssize_t         count,
 188         int             flags,
 189         xfs_iomap_t     *iomapp,
 190         int             *niomaps)
 191 {
 192         xfs_mount_t     *mp = io->io_mount;
 193         xfs_fileoff_t   offset_fsb, end_fsb;
 194         int             error = 0;
 195         int             lockmode = 0;
 196         xfs_bmbt_irec_t imap;
 197         int             nimaps = 1;
 198         int             bmapi_flags = 0;
 199         int             iomap_flags = 0;
 200
 201         if (XFS_FORCED_SHUTDOWN(mp))
 202                 return XFS_ERROR(EIO);
 203
 204         switch (flags &
 205                 (BMAPI_READ | BMAPI_WRITE | BMAPI_ALLOCATE |
 206                  BMAPI_UNWRITTEN | BMAPI_DEVICE)) {
 207         case BMAPI_READ:
 208                 xfs_iomap_enter_trace(XFS_IOMAP_READ_ENTER, io, offset, count);
 209                 lockmode = XFS_LCK_MAP_SHARED(mp, io);
 210                 bmapi_flags = XFS_BMAPI_ENTIRE;
 211                 break;
 212         case BMAPI_WRITE:
 213                 xfs_iomap_enter_trace(XFS_IOMAP_WRITE_ENTER, io, offset, count);
 214                 lockmode = XFS_ILOCK_EXCL|XFS_EXTSIZE_WR;
 215                 if (flags & BMAPI_IGNSTATE)
 216                         bmapi_flags |= XFS_BMAPI_IGSTATE|XFS_BMAPI_ENTIRE;
 217                 XFS_ILOCK(mp, io, lockmode);
 218                 break;
 219         case BMAPI_ALLOCATE:
 220                 xfs_iomap_enter_trace(XFS_IOMAP_ALLOC_ENTER, io, offset, count);
 221                 lockmode = XFS_ILOCK_SHARED|XFS_EXTSIZE_RD;
 222                 bmapi_flags = XFS_BMAPI_ENTIRE;
 223                 /* Attempt non-blocking lock */
 224                 if (flags & BMAPI_TRYLOCK) {
 225                         if (!XFS_ILOCK_NOWAIT(mp, io, lockmode))
 226                                 return XFS_ERROR(EAGAIN);
 227                 } else {
 228                         XFS_ILOCK(mp, io, lockmode);
 229                 }
 230                 break;
 231         case BMAPI_UNWRITTEN:
 232                 goto phase2;
 233         case BMAPI_DEVICE:
 234                 lockmode = XFS_LCK_MAP_SHARED(mp, io);
 235                 iomapp->iomap_target = io->io_flags & XFS_IOCORE_RT ?
 236                         mp->m_rtdev_targp : mp->m_ddev_targp;
 237                 error = 0;
 238                 *niomaps = 1;
 239                 goto out;
 240         default:
 241                 BUG();
 242         }
 243
 244         ASSERT(offset <= mp->m_maxioffset);
 245         if ((xfs_fsize_t)offset + count > mp->m_maxioffset)
 246                 count = mp->m_maxioffset - offset;
 247         end_fsb = XFS_B_TO_FSB(mp, (xfs_ufsize_t)offset + count);
 248         offset_fsb = XFS_B_TO_FSBT(mp, offset);
 249
 250         error = XFS_BMAPI(mp, NULL, io, offset_fsb,
 251                         (xfs_filblks_t)(end_fsb - offset_fsb),
 252                         bmapi_flags,  NULL, 0, &imap,
 253                         &nimaps, NULL, NULL);
 254
 255         if (error)
 256                 goto out;
 257
 258 phase2:
 259         switch (flags & (BMAPI_WRITE|BMAPI_ALLOCATE|BMAPI_UNWRITTEN)) {
 260         case BMAPI_WRITE:
 261                 /* If we found an extent, return it */
 262                 if (nimaps &&
 263                     (imap.br_startblock != HOLESTARTBLOCK) &&
 264                     (imap.br_startblock != DELAYSTARTBLOCK)) {
 265                         xfs_iomap_map_trace(XFS_IOMAP_WRITE_MAP, io,
 266                                         offset, count, iomapp, &imap, flags);
 267                         break;
 268                 }
 269
 270                 if (flags & (BMAPI_DIRECT|BMAPI_MMAP)) {
 271                         error = XFS_IOMAP_WRITE_DIRECT(mp, io, offset,
 272                                         count, flags, &imap, &nimaps, nimaps);
 273                 } else {
 274                         error = XFS_IOMAP_WRITE_DELAY(mp, io, offset, count,
 275                                         flags, &imap, &nimaps);
 276                 }
 277                 if (!error) {
 278                         xfs_iomap_map_trace(XFS_IOMAP_ALLOC_MAP, io,
 279                                         offset, count, iomapp, &imap, flags);
 280                 }
 281                 iomap_flags = IOMAP_NEW;
 282                 break;
 283         case BMAPI_ALLOCATE:
 284                 /* If we found an extent, return it */
 285                 XFS_IUNLOCK(mp, io, lockmode);
 286                 lockmode = 0;
 287
 288                 if (nimaps && !ISNULLSTARTBLOCK(imap.br_startblock)) {
 289                         xfs_iomap_map_trace(XFS_IOMAP_WRITE_MAP, io,
 290                                         offset, count, iomapp, &imap, flags);
 291                         break;
 292                 }
 293
 294                 error = XFS_IOMAP_WRITE_ALLOCATE(mp, io, offset, count,
 295                                                  &imap, &nimaps);
 296                 break;
 297         case BMAPI_UNWRITTEN:
 298                 lockmode = 0;
 299                 error = XFS_IOMAP_WRITE_UNWRITTEN(mp, io, offset, count);
 300                 nimaps = 0;
 301                 break;
 302         }
 303
 304         if (nimaps) {
 305                 *niomaps = xfs_imap_to_bmap(io, offset, &imap,
 306                                             iomapp, nimaps, *niomaps, iomap_flags);
 307         } else if (niomaps) {
 308                 *niomaps = 0;
 309         }
 310
 311 out:
 312         if (lockmode)
 313                 XFS_IUNLOCK(mp, io, lockmode);
 314         return XFS_ERROR(error);
 315 }
 316
 317 STATIC int
 318 xfs_iomap_eof_align_last_fsb(
 319         xfs_mount_t     *mp,
 320         xfs_iocore_t    *io,
 321         xfs_fsize_t     isize,
 322         xfs_extlen_t    extsize,
 323         xfs_fileoff_t   *last_fsb)
 324 {
 325         xfs_fileoff_t   new_last_fsb = 0;
 326         xfs_extlen_t    align;
 327         int             eof, error;
 328
 329         if (io->io_flags & XFS_IOCORE_RT)
 330                 ;
 331         /*
 332          * If mounted with the "-o swalloc" option, roundup the allocation
 333          * request to a stripe width boundary if the file size is >=
 334          * stripe width and we are allocating past the allocation eof.
 335          */
 336         else if (mp->m_swidth && (mp->m_flags & XFS_MOUNT_SWALLOC) &&
 337                 (isize >= XFS_FSB_TO_B(mp, mp->m_swidth)))
 338                 new_last_fsb = roundup_64(*last_fsb, mp->m_swidth);
 339         /*
 340          * Roundup the allocation request to a stripe unit (m_dalign) boundary
 341          * if the file size is >= stripe unit size, and we are allocating past
 342          * the allocation eof.
 343          */
 344         else if (mp->m_dalign && (isize >= XFS_FSB_TO_B(mp, mp->m_dalign)))
 345                 new_last_fsb = roundup_64(*last_fsb, mp->m_dalign);
 346
 347         /*
 348          * Always round up the allocation request to an extent boundary
 349          * (when file on a real-time subvolume or has di_extsize hint).
 350          */
 351         if (extsize) {
 352                 if (new_last_fsb)
 353                         align = roundup_64(new_last_fsb, extsize);
 354                 else
 355                         align = extsize;
 356                 new_last_fsb = roundup_64(*last_fsb, align);
 357         }
 358
 359         if (new_last_fsb) {
 360                 error = XFS_BMAP_EOF(mp, io, new_last_fsb, XFS_DATA_FORK, &eof);
 361                 if (error)
 362                         return error;
 363                 if (eof)
 364                         *last_fsb = new_last_fsb;
 365         }
 366         return 0;
 367 }
 368
 369 STATIC int
 370 xfs_flush_space(
 371         xfs_inode_t     *ip,
 372         int             *fsynced,
 373         int             *ioflags)
 374 {
 375         switch (*fsynced) {
 376         case 0:
 377                 if (ip->i_delayed_blks) {
 378                         xfs_iunlock(ip, XFS_ILOCK_EXCL);
 379                         xfs_flush_inode(ip);
 380                         xfs_ilock(ip, XFS_ILOCK_EXCL);
 381                         *fsynced = 1;
 382                 } else {
 383                         *ioflags |= BMAPI_SYNC;
 384                         *fsynced = 2;
 385                 }
 386                 return 0;
 387         case 1:
 388                 *fsynced = 2;
 389                 *ioflags |= BMAPI_SYNC;
 390                 return 0;
 391         case 2:
 392                 xfs_iunlock(ip, XFS_ILOCK_EXCL);
 393                 xfs_flush_device(ip);
 394                 xfs_ilock(ip, XFS_ILOCK_EXCL);
 395                 *fsynced = 3;
 396                 return 0;
 397         }
 398         return 1;
 399 }
 400
 401 int
 402 xfs_iomap_write_direct(
 403         xfs_inode_t     *ip,
 404         xfs_off_t       offset,
 405         size_t          count,
 406         int             flags,
 407         xfs_bmbt_irec_t *ret_imap,
 408         int             *nmaps,
 409         int             found)
 410 {
 411         xfs_mount_t     *mp = ip->i_mount;
 412         xfs_iocore_t    *io = &ip->i_iocore;
 413         xfs_fileoff_t   offset_fsb;
 414         xfs_fileoff_t   last_fsb;
 415         xfs_filblks_t   count_fsb, resaligned;
 416         xfs_fsblock_t   firstfsb;
 417         xfs_extlen_t    extsz, temp;
 418         xfs_fsize_t     isize;
 419         int             nimaps;
 420         int             bmapi_flag;
 421         int             quota_flag;
 422         int             rt;
 423         xfs_trans_t     *tp;
 424         xfs_bmbt_irec_t imap;
 425         xfs_bmap_free_t free_list;
 426         uint            qblocks, resblks, resrtextents;
 427         int             committed;
 428         int             error;
 429
 430         /*
 431          * Make sure that the dquots are there. This doesn't hold
 432          * the ilock across a disk read.
 433          */
 434         error = XFS_QM_DQATTACH(ip->i_mount, ip, XFS_QMOPT_ILOCKED);
 435         if (error)
 436                 return XFS_ERROR(error);
 437
 438         rt = XFS_IS_REALTIME_INODE(ip);
 439         if (unlikely(rt)) {
 440                 if (!(extsz = ip->i_d.di_extsize))
 441                         extsz = mp->m_sb.sb_rextsize;
 442         } else {
 443                 extsz = ip->i_d.di_extsize;
 444         }
 445
 446         isize = ip->i_d.di_size;
 447         if (io->io_new_size > isize)
 448                 isize = io->io_new_size;
 449
 450         offset_fsb = XFS_B_TO_FSBT(mp, offset);
 451         last_fsb = XFS_B_TO_FSB(mp, ((xfs_ufsize_t)(offset + count)));
 452         if ((offset + count) > isize) {
 453                 error = xfs_iomap_eof_align_last_fsb(mp, io, isize, extsz,
 454                                                         &last_fsb);
 455                 if (error)
 456                         goto error_out;
 457         } else {
 458                 if (found && (ret_imap->br_startblock == HOLESTARTBLOCK))
 459                         last_fsb = MIN(last_fsb, (xfs_fileoff_t)
 460                                         ret_imap->br_blockcount +
 461                                         ret_imap->br_startoff);
 462         }
 463         count_fsb = last_fsb - offset_fsb;
 464         ASSERT(count_fsb > 0);
 465
 466         resaligned = count_fsb;
 467         if (unlikely(extsz)) {
 468                 if ((temp = do_mod(offset_fsb, extsz)))
 469                         resaligned += temp;
 470                 if ((temp = do_mod(resaligned, extsz)))
 471                         resaligned += extsz - temp;
 472         }
 473
 474         if (unlikely(rt)) {
 475                 resrtextents = qblocks = resaligned;
 476                 resrtextents /= mp->m_sb.sb_rextsize;
 477                 resblks = XFS_DIOSTRAT_SPACE_RES(mp, 0);
 478                 quota_flag = XFS_QMOPT_RES_RTBLKS;
 479         } else {
 480                 resrtextents = 0;
 481                 resblks = qblocks = XFS_DIOSTRAT_SPACE_RES(mp, resaligned);
 482                 quota_flag = XFS_QMOPT_RES_REGBLKS;
 483         }
 484
 485         /*
 486          * Allocate and setup the transaction
 487          */
 488         xfs_iunlock(ip, XFS_ILOCK_EXCL);
 489         tp = xfs_trans_alloc(mp, XFS_TRANS_DIOSTRAT);
 490         error = xfs_trans_reserve(tp, resblks,
 491                         XFS_WRITE_LOG_RES(mp), resrtextents,
 492                         XFS_TRANS_PERM_LOG_RES,
 493                         XFS_WRITE_LOG_COUNT);
 494         /*
 495          * Check for running out of space, note: need lock to return
 496          */
 497         if (error)
 498                 xfs_trans_cancel(tp, 0);
 499         xfs_ilock(ip, XFS_ILOCK_EXCL);
 500         if (error)
 501                 goto error_out;
 502
 503         error = XFS_TRANS_RESERVE_QUOTA_NBLKS(mp, tp, ip,
 504                                               qblocks, 0, quota_flag);
 505         if (error)
 506                 goto error1;
 507
 508         xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
 509         xfs_trans_ihold(tp, ip);
 510
 511         bmapi_flag = XFS_BMAPI_WRITE;
 512         if ((flags & BMAPI_DIRECT) && (offset < ip->i_d.di_size || extsz))
 513                 bmapi_flag |= XFS_BMAPI_PREALLOC;
 514
 515         /*
 516          * Issue the xfs_bmapi() call to allocate the blocks
 517          */
 518         XFS_BMAP_INIT(&free_list, &firstfsb);
 519         nimaps = 1;
 520         error = XFS_BMAPI(mp, tp, io, offset_fsb, count_fsb, bmapi_flag,
 521                 &firstfsb, 0, &imap, &nimaps, &free_list, NULL);
 522         if (error)
 523                 goto error0;
 524
 525         /*
 526          * Complete the transaction
 527          */
 528         error = xfs_bmap_finish(&tp, &free_list, firstfsb, &committed);
 529         if (error)
 530                 goto error0;
 531         error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES, NULL);
 532         if (error)
 533                 goto error_out;
 534
 535         /*
 536          * Copy any maps to caller's array and return any error.
 537          */
 538         if (nimaps == 0) {
 539                 error = (ENOSPC);
 540                 goto error_out;
 541         }
 542
 543         *ret_imap = imap;
 544         *nmaps = 1;
 545         if ( !(io->io_flags & XFS_IOCORE_RT)  && !ret_imap->br_startblock) {
 546                 cmn_err(CE_PANIC,"Access to block zero:  fs <%s> inode: %lld "
 547                         "start_block : %llx start_off : %llx blkcnt : %llx "
 548                         "extent-state : %x \n",
 549                         (ip->i_mount)->m_fsname,
 550                         (long long)ip->i_ino,
 551                         (unsigned long long)ret_imap->br_startblock,
 552                         (unsigned long long)ret_imap->br_startoff,
 553                         (unsigned long long)ret_imap->br_blockcount,
 554                         ret_imap->br_state);
 555         }
 556         return 0;
 557
 558 error0: /* Cancel bmap, unlock inode, unreserve quota blocks, cancel trans */
 559         xfs_bmap_cancel(&free_list);
 560         XFS_TRANS_UNRESERVE_QUOTA_NBLKS(mp, tp, ip, qblocks, 0, quota_flag);
 561
 562 error1: /* Just cancel transaction */
 563         xfs_trans_cancel(tp, XFS_TRANS_RELEASE_LOG_RES | XFS_TRANS_ABORT);
 564         *nmaps = 0;     /* nothing set-up here */
 565
 566 error_out:
 567         return XFS_ERROR(error);
 568 }
 569
 570 /*
 571  * If the caller is doing a write at the end of the file,
 572  * then extend the allocation out to the file system's write
 573  * iosize.  We clean up any extra space left over when the
 574  * file is closed in xfs_inactive().
 575  *
 576  * For sync writes, we are flushing delayed allocate space to
 577  * try to make additional space available for allocation near
 578  * the filesystem full boundary - preallocation hurts in that
 579  * situation, of course.
 580  */
 581 STATIC int
 582 xfs_iomap_eof_want_preallocate(
 583         xfs_mount_t     *mp,
 584         xfs_iocore_t    *io,
 585         xfs_fsize_t     isize,
 586         xfs_off_t       offset,
 587         size_t          count,
 588         int             ioflag,
 589         xfs_bmbt_irec_t *imap,
 590         int             nimaps,
 591         int             *prealloc)
 592 {
 593         xfs_fileoff_t   start_fsb;
 594         xfs_filblks_t   count_fsb;
 595         xfs_fsblock_t   firstblock;
 596         int             n, error, imaps;
 597
 598         *prealloc = 0;
 599         if ((ioflag & BMAPI_SYNC) || (offset + count) <= isize)
 600                 return 0;
 601
 602         /*
 603          * If there are any real blocks past eof, then don't
 604          * do any speculative allocation.
 605          */
 606         start_fsb = XFS_B_TO_FSBT(mp, ((xfs_ufsize_t)(offset + count - 1)));
 607         count_fsb = XFS_B_TO_FSB(mp, (xfs_ufsize_t)XFS_MAXIOFFSET(mp));
 608         while (count_fsb > 0) {
 609                 imaps = nimaps;
 610                 firstblock = NULLFSBLOCK;
 611                 error = XFS_BMAPI(mp, NULL, io, start_fsb, count_fsb, 0,
 612                                   &firstblock, 0, imap, &imaps, NULL, NULL);
 613                 if (error)
 614                         return error;
 615                 for (n = 0; n < imaps; n++) {
 616                         if ((imap[n].br_startblock != HOLESTARTBLOCK) &&
 617                             (imap[n].br_startblock != DELAYSTARTBLOCK))
 618                                 return 0;
 619                         start_fsb += imap[n].br_blockcount;
 620                         count_fsb -= imap[n].br_blockcount;
 621                 }
 622         }
 623         *prealloc = 1;
 624         return 0;
 625 }
 626
 627 int
 628 xfs_iomap_write_delay(
 629         xfs_inode_t     *ip,
 630         xfs_off_t       offset,
 631         size_t          count,
 632         int             ioflag,
 633         xfs_bmbt_irec_t *ret_imap,
 634         int             *nmaps)
 635 {
 636         xfs_mount_t     *mp = ip->i_mount;
 637         xfs_iocore_t    *io = &ip->i_iocore;
 638         xfs_fileoff_t   offset_fsb;
 639         xfs_fileoff_t   last_fsb;
 640         xfs_off_t       aligned_offset;
 641         xfs_fileoff_t   ioalign;
 642         xfs_fsblock_t   firstblock;
 643         xfs_extlen_t    extsz;
 644         xfs_fsize_t     isize;
 645         int             nimaps;
 646         xfs_bmbt_irec_t imap[XFS_WRITE_IMAPS];
 647         int             prealloc, fsynced = 0;
 648         int             error;
 649
 650         ASSERT(ismrlocked(&ip->i_lock, MR_UPDATE) != 0);
 651
 652         /*
 653          * Make sure that the dquots are there. This doesn't hold
 654          * the ilock across a disk read.
 655          */
 656         error = XFS_QM_DQATTACH(mp, ip, XFS_QMOPT_ILOCKED);
 657         if (error)
 658                 return XFS_ERROR(error);
 659
 660         if (XFS_IS_REALTIME_INODE(ip)) {
 661                 if (!(extsz = ip->i_d.di_extsize))
 662                         extsz = mp->m_sb.sb_rextsize;
 663         } else {
 664                 extsz = ip->i_d.di_extsize;
 665         }
 666
 667         offset_fsb = XFS_B_TO_FSBT(mp, offset);
 668
 669 retry:
 670         isize = ip->i_d.di_size;
 671         if (io->io_new_size > isize)
 672                 isize = io->io_new_size;
 673
 674         error = xfs_iomap_eof_want_preallocate(mp, io, isize, offset, count,
 675                                 ioflag, imap, XFS_WRITE_IMAPS, &prealloc);
 676         if (error)
 677                 return error;
 678
 679         if (prealloc) {
 680                 aligned_offset = XFS_WRITEIO_ALIGN(mp, (offset + count - 1));
 681                 ioalign = XFS_B_TO_FSBT(mp, aligned_offset);
 682                 last_fsb = ioalign + mp->m_writeio_blocks;
 683         } else {
 684                 last_fsb = XFS_B_TO_FSB(mp, ((xfs_ufsize_t)(offset + count)));
 685         }
 686
 687         if (prealloc || extsz) {
 688                 error = xfs_iomap_eof_align_last_fsb(mp, io, isize, extsz,
 689                                                         &last_fsb);
 690                 if (error)
 691                         return error;
 692         }
 693
 694         nimaps = XFS_WRITE_IMAPS;
 695         firstblock = NULLFSBLOCK;
 696         error = XFS_BMAPI(mp, NULL, io, offset_fsb,
 697                           (xfs_filblks_t)(last_fsb - offset_fsb),
 698                           XFS_BMAPI_DELAY | XFS_BMAPI_WRITE |
 699                           XFS_BMAPI_ENTIRE, &firstblock, 1, imap,
 700                           &nimaps, NULL, NULL);
 701         if (error && (error != ENOSPC))
 702                 return XFS_ERROR(error);
 703
 704         /*
 705          * If bmapi returned us nothing, and if we didn't get back EDQUOT,
 706          * then we must have run out of space - flush delalloc, and retry..
 707          */
 708         if (nimaps == 0) {
 709                 xfs_iomap_enter_trace(XFS_IOMAP_WRITE_NOSPACE,
 710                                         io, offset, count);
 711                 if (xfs_flush_space(ip, &fsynced, &ioflag))
 712                         return XFS_ERROR(ENOSPC);
 713
 714                 error = 0;
 715                 goto retry;
 716         }
 717
 718         if (!(io->io_flags & XFS_IOCORE_RT)  && !ret_imap->br_startblock) {
 719                 cmn_err(CE_PANIC,"Access to block zero:  fs <%s> inode: %lld "
 720                         "start_block : %llx start_off : %llx blkcnt : %llx "
 721                         "extent-state : %x \n",
 722                         (ip->i_mount)->m_fsname,
 723                         (long long)ip->i_ino,
 724                         (unsigned long long)ret_imap->br_startblock,
 725                         (unsigned long long)ret_imap->br_startoff,
 726                         (unsigned long long)ret_imap->br_blockcount,
 727                         ret_imap->br_state);
 728         }
 729
 730         *ret_imap = imap[0];
 731         *nmaps = 1;
 732
 733         return 0;
 734 }
 735
 736 /*
 737  * Pass in a delayed allocate extent, convert it to real extents;
 738  * return to the caller the extent we create which maps on top of
 739  * the originating callers request.
 740  *
 741  * Called without a lock on the inode.
 742  */
 743 int
 744 xfs_iomap_write_allocate(
 745         xfs_inode_t     *ip,
 746         xfs_off_t       offset,
 747         size_t          count,
 748         xfs_bmbt_irec_t *map,
 749         int             *retmap)
 750 {
 751         xfs_mount_t     *mp = ip->i_mount;
 752         xfs_iocore_t    *io = &ip->i_iocore;
 753         xfs_fileoff_t   offset_fsb, last_block;
 754         xfs_fileoff_t   end_fsb, map_start_fsb;
 755         xfs_fsblock_t   first_block;
 756         xfs_bmap_free_t free_list;
 757         xfs_filblks_t   count_fsb;
 758         xfs_bmbt_irec_t imap[XFS_STRAT_WRITE_IMAPS];
 759         xfs_trans_t     *tp;
 760         int             i, nimaps, committed;
 761         int             error = 0;
 762         int             nres;
 763
 764         *retmap = 0;
 765
 766         /*
 767          * Make sure that the dquots are there.
 768          */
 769         if ((error = XFS_QM_DQATTACH(mp, ip, 0)))
 770                 return XFS_ERROR(error);
 771
 772         offset_fsb = XFS_B_TO_FSBT(mp, offset);
 773         count_fsb = map->br_blockcount;
 774         map_start_fsb = map->br_startoff;
 775
 776         XFS_STATS_ADD(xs_xstrat_bytes, XFS_FSB_TO_B(mp, count_fsb));
 777
 778         while (count_fsb != 0) {
 779                 /*
 780                  * Set up a transaction with which to allocate the
 781                  * backing store for the file.  Do allocations in a
 782                  * loop until we get some space in the range we are
 783                  * interested in.  The other space that might be allocated
 784                  * is in the delayed allocation extent on which we sit
 785                  * but before our buffer starts.
 786                  */
 787
 788                 nimaps = 0;
 789                 while (nimaps == 0) {
 790                         tp = xfs_trans_alloc(mp, XFS_TRANS_STRAT_WRITE);
 791                         nres = XFS_EXTENTADD_SPACE_RES(mp, XFS_DATA_FORK);
 792                         error = xfs_trans_reserve(tp, nres,
 793                                         XFS_WRITE_LOG_RES(mp),
 794                                         0, XFS_TRANS_PERM_LOG_RES,
 795                                         XFS_WRITE_LOG_COUNT);
 796                         if (error == ENOSPC) {
 797                                 error = xfs_trans_reserve(tp, 0,
 798                                                 XFS_WRITE_LOG_RES(mp),
 799                                                 0,
 800                                                 XFS_TRANS_PERM_LOG_RES,
 801                                                 XFS_WRITE_LOG_COUNT);
 802                         }
 803                         if (error) {
 804                                 xfs_trans_cancel(tp, 0);
 805                                 return XFS_ERROR(error);
 806                         }
 807                         xfs_ilock(ip, XFS_ILOCK_EXCL);
 808                         xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
 809                         xfs_trans_ihold(tp, ip);
 810
 811                         XFS_BMAP_INIT(&free_list, &first_block);
 812
 813                         nimaps = XFS_STRAT_WRITE_IMAPS;
 814                         /*
 815                          * Ensure we don't go beyond eof - it is possible
 816                          * the extents changed since we did the read call,
 817                          * we dropped the ilock in the interim.
 818                          */
 819
 820                         end_fsb = XFS_B_TO_FSB(mp, ip->i_d.di_size);
 821                         xfs_bmap_last_offset(NULL, ip, &last_block,
 822                                 XFS_DATA_FORK);
 823                         last_block = XFS_FILEOFF_MAX(last_block, end_fsb);
 824                         if ((map_start_fsb + count_fsb) > last_block) {
 825                                 count_fsb = last_block - map_start_fsb;
 826                                 if (count_fsb == 0) {
 827                                         error = EAGAIN;
 828                                         goto trans_cancel;
 829                                 }
 830                         }
 831
 832                         /* Go get the actual blocks */
 833                         error = XFS_BMAPI(mp, tp, io, map_start_fsb, count_fsb,
 834                                         XFS_BMAPI_WRITE, &first_block, 1,
 835                                         imap, &nimaps, &free_list, NULL);
 836                         if (error)
 837                                 goto trans_cancel;
 838
 839                         error = xfs_bmap_finish(&tp, &free_list,
 840                                         first_block, &committed);
 841                         if (error)
 842                                 goto trans_cancel;
 843
 844                         error = xfs_trans_commit(tp,
 845                                         XFS_TRANS_RELEASE_LOG_RES, NULL);
 846                         if (error)
 847                                 goto error0;
 848
 849                         xfs_iunlock(ip, XFS_ILOCK_EXCL);
 850                 }
 851
 852                 /*
 853                  * See if we were able to allocate an extent that
 854                  * covers at least part of the callers request
 855                  */
 856
 857                 for (i = 0; i < nimaps; i++) {
 858                         if (!(io->io_flags & XFS_IOCORE_RT)  &&
 859                             !imap[i].br_startblock) {
 860                                 cmn_err(CE_PANIC,"Access to block zero:  "
 861                                         "fs <%s> inode: %lld "
 862                                         "start_block : %llx start_off : %llx "
 863                                         "blkcnt : %llx extent-state : %x \n",
 864                                         (ip->i_mount)->m_fsname,
 865                                         (long long)ip->i_ino,
 866                                         (unsigned long long)
 867                                                 imap[i].br_startblock,
 868                                         (unsigned long long)
 869                                                 imap[i].br_startoff,
 870                                         (unsigned long long)
 871                                                 imap[i].br_blockcount,
 872                                         imap[i].br_state);
 873                         }
 874                         if ((offset_fsb >= imap[i].br_startoff) &&
 875                             (offset_fsb < (imap[i].br_startoff +
 876                                            imap[i].br_blockcount))) {
 877                                 *map = imap[i];
 878                                 *retmap = 1;
 879                                 XFS_STATS_INC(xs_xstrat_quick);
 880                                 return 0;
 881                         }
 882                         count_fsb -= imap[i].br_blockcount;
 883                 }
 884
 885                 /* So far we have not mapped the requested part of the
 886                  * file, just surrounding data, try again.
 887                  */
 888                 nimaps--;
 889                 map_start_fsb = imap[nimaps].br_startoff +
 890                                 imap[nimaps].br_blockcount;
 891         }
 892
 893 trans_cancel:
 894         xfs_bmap_cancel(&free_list);
 895         xfs_trans_cancel(tp, XFS_TRANS_RELEASE_LOG_RES | XFS_TRANS_ABORT);
 896 error0:
 897         xfs_iunlock(ip, XFS_ILOCK_EXCL);
 898         return XFS_ERROR(error);
 899 }
 900
 901 int
 902 xfs_iomap_write_unwritten(
 903         xfs_inode_t     *ip,
 904         xfs_off_t       offset,
 905         size_t          count)
 906 {
 907         xfs_mount_t     *mp = ip->i_mount;
 908         xfs_iocore_t    *io = &ip->i_iocore;
 909         xfs_fileoff_t   offset_fsb;
 910         xfs_filblks_t   count_fsb;
 911         xfs_filblks_t   numblks_fsb;
 912         xfs_fsblock_t   firstfsb;
 913         int             nimaps;
 914         xfs_trans_t     *tp;
 915         xfs_bmbt_irec_t imap;
 916         xfs_bmap_free_t free_list;
 917         uint            resblks;
 918         int             committed;
 919         int             error;
 920
 921         xfs_iomap_enter_trace(XFS_IOMAP_UNWRITTEN,
 922                                 &ip->i_iocore, offset, count);
 923
 924         offset_fsb = XFS_B_TO_FSBT(mp, offset);
 925         count_fsb = XFS_B_TO_FSB(mp, (xfs_ufsize_t)offset + count);
 926         count_fsb = (xfs_filblks_t)(count_fsb - offset_fsb);
 927
 928         resblks = XFS_DIOSTRAT_SPACE_RES(mp, 0) << 1;
 929
 930         do {
 931                 /*
 932                  * set up a transaction to convert the range of extents
 933                  * from unwritten to real. Do allocations in a loop until
 934                  * we have covered the range passed in.
 935                  */
 936
 937                 tp = xfs_trans_alloc(mp, XFS_TRANS_STRAT_WRITE);
 938                 error = xfs_trans_reserve(tp, resblks,
 939                                 XFS_WRITE_LOG_RES(mp), 0,
 940                                 XFS_TRANS_PERM_LOG_RES,
 941                                 XFS_WRITE_LOG_COUNT);
 942                 if (error) {
 943                         xfs_trans_cancel(tp, 0);
 944                         goto error0;
 945                 }
 946
 947                 xfs_ilock(ip, XFS_ILOCK_EXCL);
 948                 xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
 949                 xfs_trans_ihold(tp, ip);
 950
 951                 /*
 952                  * Modify the unwritten extent state of the buffer.
 953                  */
 954                 XFS_BMAP_INIT(&free_list, &firstfsb);
 955                 nimaps = 1;
 956                 error = XFS_BMAPI(mp, tp, io, offset_fsb, count_fsb,
 957                                   XFS_BMAPI_WRITE|XFS_BMAPI_CONVERT, &firstfsb,
 958                                   1, &imap, &nimaps, &free_list, NULL);
 959                 if (error)
 960                         goto error_on_bmapi_transaction;
 961
 962                 error = xfs_bmap_finish(&(tp), &(free_list),
 963                                 firstfsb, &committed);
 964                 if (error)
 965                         goto error_on_bmapi_transaction;
 966
 967                 error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES, NULL);
 968                 xfs_iunlock(ip, XFS_ILOCK_EXCL);
 969                 if (error)
 970                         goto error0;
 971
 972                 if ( !(io->io_flags & XFS_IOCORE_RT)  && !imap.br_startblock) {
 973                         cmn_err(CE_PANIC,"Access to block zero:  fs <%s> "
 974                                 "inode: %lld start_block : %llx start_off : "
 975                                 "%llx blkcnt : %llx extent-state : %x \n",
 976                                 (ip->i_mount)->m_fsname,
 977                                 (long long)ip->i_ino,
 978                                 (unsigned long long)imap.br_startblock,
 979                                 (unsigned long long)imap.br_startoff,
 980                                 (unsigned long long)imap.br_blockcount,
 981                                 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 }