git.oblomov.eu Git - linux-2.6/blob - fs/xfs/xfs_iomap.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_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_dir.h"
  27 #include "xfs_dir2.h"
  28 #include "xfs_alloc.h"
  29 #include "xfs_dmapi.h"
  30 #include "xfs_quota.h"
  31 #include "xfs_mount.h"
  32 #include "xfs_bmap_btree.h"
  33 #include "xfs_alloc_btree.h"
  34 #include "xfs_ialloc_btree.h"
  35 #include "xfs_dir_sf.h"
  36 #include "xfs_dir2_sf.h"
  37 #include "xfs_attr_sf.h"
  38 #include "xfs_dinode.h"
  39 #include "xfs_inode.h"
  40 #include "xfs_ialloc.h"
  41 #include "xfs_btree.h"
  42 #include "xfs_bmap.h"
  43 #include "xfs_bit.h"
  44 #include "xfs_rtalloc.h"
  45 #include "xfs_error.h"
  46 #include "xfs_itable.h"
  47 #include "xfs_rw.h"
  48 #include "xfs_acl.h"
  49 #include "xfs_cap.h"
  50 #include "xfs_mac.h"
  51 #include "xfs_attr.h"
  52 #include "xfs_buf_item.h"
  53 #include "xfs_trans_space.h"
  54 #include "xfs_utils.h"
  55 #include "xfs_iomap.h"
  56
  57 #if defined(XFS_RW_TRACE)
  58 void
  59 xfs_iomap_enter_trace(
  60         int             tag,
  61         xfs_iocore_t    *io,
  62         xfs_off_t       offset,
  63         ssize_t         count)
  64 {
  65         xfs_inode_t     *ip = XFS_IO_INODE(io);
  66
  67         if (!ip->i_rwtrace)
  68                 return;
  69
  70         ktrace_enter(ip->i_rwtrace,
  71                 (void *)((unsigned long)tag),
  72                 (void *)ip,
  73                 (void *)((unsigned long)((ip->i_d.di_size >> 32) & 0xffffffff)),
  74                 (void *)((unsigned long)(ip->i_d.di_size & 0xffffffff)),
  75                 (void *)((unsigned long)((offset >> 32) & 0xffffffff)),
  76                 (void *)((unsigned long)(offset & 0xffffffff)),
  77                 (void *)((unsigned long)count),
  78                 (void *)((unsigned long)((io->io_new_size >> 32) & 0xffffffff)),
  79                 (void *)((unsigned long)(io->io_new_size & 0xffffffff)),
  80                 (void *)NULL,
  81                 (void *)NULL,
  82                 (void *)NULL,
  83                 (void *)NULL,
  84                 (void *)NULL,
  85                 (void *)NULL,
  86                 (void *)NULL);
  87 }
  88
  89 void
  90 xfs_iomap_map_trace(
  91         int             tag,
  92         xfs_iocore_t    *io,
  93         xfs_off_t       offset,
  94         ssize_t         count,
  95         xfs_iomap_t     *iomapp,
  96         xfs_bmbt_irec_t *imapp,
  97         int             flags)
  98 {
  99         xfs_inode_t     *ip = XFS_IO_INODE(io);
 100
 101         if (!ip->i_rwtrace)
 102                 return;
 103
 104         ktrace_enter(ip->i_rwtrace,
 105                 (void *)((unsigned long)tag),
 106                 (void *)ip,
 107                 (void *)((unsigned long)((ip->i_d.di_size >> 32) & 0xffffffff)),
 108                 (void *)((unsigned long)(ip->i_d.di_size & 0xffffffff)),
 109                 (void *)((unsigned long)((offset >> 32) & 0xffffffff)),
 110                 (void *)((unsigned long)(offset & 0xffffffff)),
 111                 (void *)((unsigned long)count),
 112                 (void *)((unsigned long)flags),
 113                 (void *)((unsigned long)((iomapp->iomap_offset >> 32) & 0xffffffff)),
 114                 (void *)((unsigned long)(iomapp->iomap_offset & 0xffffffff)),
 115                 (void *)((unsigned long)(iomapp->iomap_delta)),
 116                 (void *)((unsigned long)(iomapp->iomap_bsize)),
 117                 (void *)((unsigned long)(iomapp->iomap_bn)),
 118                 (void *)(__psint_t)(imapp->br_startoff),
 119                 (void *)((unsigned long)(imapp->br_blockcount)),
 120                 (void *)(__psint_t)(imapp->br_startblock));
 121 }
 122 #else
 123 #define xfs_iomap_enter_trace(tag, io, offset, count)
 124 #define xfs_iomap_map_trace(tag, io, offset, count, iomapp, imapp, flags)
 125 #endif
 126
 127 #define XFS_WRITEIO_ALIGN(mp,off)       (((off) >> mp->m_writeio_log) \
 128                                                 << mp->m_writeio_log)
 129 #define XFS_STRAT_WRITE_IMAPS   2
 130 #define XFS_WRITE_IMAPS         XFS_BMAP_MAX_NMAP
 131
 132 STATIC int
 133 xfs_imap_to_bmap(
 134         xfs_iocore_t    *io,
 135         xfs_off_t       offset,
 136         xfs_bmbt_irec_t *imap,
 137         xfs_iomap_t     *iomapp,
 138         int             imaps,                  /* Number of imap entries */
 139         int             iomaps,                 /* Number of iomap entries */
 140         int             flags)
 141 {
 142         xfs_mount_t     *mp;
 143         xfs_fsize_t     nisize;
 144         int             pbm;
 145         xfs_fsblock_t   start_block;
 146
 147         mp = io->io_mount;
 148         nisize = XFS_SIZE(mp, io);
 149         if (io->io_new_size > nisize)
 150                 nisize = io->io_new_size;
 151
 152         for (pbm = 0; imaps && pbm < iomaps; imaps--, iomapp++, imap++, pbm++) {
 153                 iomapp->iomap_offset = XFS_FSB_TO_B(mp, imap->br_startoff);
 154                 iomapp->iomap_delta = offset - iomapp->iomap_offset;
 155                 iomapp->iomap_bsize = XFS_FSB_TO_B(mp, imap->br_blockcount);
 156                 iomapp->iomap_flags = flags;
 157
 158                 if (io->io_flags & XFS_IOCORE_RT) {
 159                         iomapp->iomap_flags |= IOMAP_REALTIME;
 160                         iomapp->iomap_target = mp->m_rtdev_targp;
 161                 } else {
 162                         iomapp->iomap_target = mp->m_ddev_targp;
 163                 }
 164                 start_block = imap->br_startblock;
 165                 if (start_block == HOLESTARTBLOCK) {
 166                         iomapp->iomap_bn = IOMAP_DADDR_NULL;
 167                         iomapp->iomap_flags |= IOMAP_HOLE;
 168                 } else if (start_block == DELAYSTARTBLOCK) {
 169                         iomapp->iomap_bn = IOMAP_DADDR_NULL;
 170                         iomapp->iomap_flags |= IOMAP_DELAY;
 171                 } else {
 172                         iomapp->iomap_bn = XFS_FSB_TO_DB_IO(io, start_block);
 173                         if (ISUNWRITTEN(imap))
 174                                 iomapp->iomap_flags |= IOMAP_UNWRITTEN;
 175                 }
 176
 177                 if ((iomapp->iomap_offset + iomapp->iomap_bsize) >= nisize) {
 178                         iomapp->iomap_flags |= IOMAP_EOF;
 179                 }
 180
 181                 offset += iomapp->iomap_bsize - iomapp->iomap_delta;
 182         }
 183         return pbm;     /* Return the number filled */
 184 }
 185
 186 int
 187 xfs_iomap(
 188         xfs_iocore_t    *io,
 189         xfs_off_t       offset,
 190         ssize_t         count,
 191         int             flags,
 192         xfs_iomap_t     *iomapp,
 193         int             *niomaps)
 194 {
 195         xfs_mount_t     *mp = io->io_mount;
 196         xfs_fileoff_t   offset_fsb, end_fsb;
 197         int             error = 0;
 198         int             lockmode = 0;
 199         xfs_bmbt_irec_t imap;
 200         int             nimaps = 1;
 201         int             bmapi_flags = 0;
 202         int             iomap_flags = 0;
 203
 204         if (XFS_FORCED_SHUTDOWN(mp))
 205                 return XFS_ERROR(EIO);
 206
 207         switch (flags &
 208                 (BMAPI_READ | BMAPI_WRITE | BMAPI_ALLOCATE |
 209                  BMAPI_UNWRITTEN | BMAPI_DEVICE)) {
 210         case BMAPI_READ:
 211                 xfs_iomap_enter_trace(XFS_IOMAP_READ_ENTER, io, offset, count);
 212                 lockmode = XFS_LCK_MAP_SHARED(mp, io);
 213                 bmapi_flags = XFS_BMAPI_ENTIRE;
 214                 break;
 215         case BMAPI_WRITE:
 216                 xfs_iomap_enter_trace(XFS_IOMAP_WRITE_ENTER, io, offset, count);
 217                 lockmode = XFS_ILOCK_EXCL|XFS_EXTSIZE_WR;
 218                 if (flags & BMAPI_IGNSTATE)
 219                         bmapi_flags |= XFS_BMAPI_IGSTATE|XFS_BMAPI_ENTIRE;
 220                 XFS_ILOCK(mp, io, lockmode);
 221                 break;
 222         case BMAPI_ALLOCATE:
 223                 xfs_iomap_enter_trace(XFS_IOMAP_ALLOC_ENTER, io, offset, count);
 224                 lockmode = XFS_ILOCK_SHARED|XFS_EXTSIZE_RD;
 225                 bmapi_flags = XFS_BMAPI_ENTIRE;
 226                 /* Attempt non-blocking lock */
 227                 if (flags & BMAPI_TRYLOCK) {
 228                         if (!XFS_ILOCK_NOWAIT(mp, io, lockmode))
 229                                 return XFS_ERROR(EAGAIN);
 230                 } else {
 231                         XFS_ILOCK(mp, io, lockmode);
 232                 }
 233                 break;
 234         case BMAPI_UNWRITTEN:
 235                 goto phase2;
 236         case BMAPI_DEVICE:
 237                 lockmode = XFS_LCK_MAP_SHARED(mp, io);
 238                 iomapp->iomap_target = io->io_flags & XFS_IOCORE_RT ?
 239                         mp->m_rtdev_targp : mp->m_ddev_targp;
 240                 error = 0;
 241                 *niomaps = 1;
 242                 goto out;
 243         default:
 244                 BUG();
 245         }
 246
 247         ASSERT(offset <= mp->m_maxioffset);
 248         if ((xfs_fsize_t)offset + count > mp->m_maxioffset)
 249                 count = mp->m_maxioffset - offset;
 250         end_fsb = XFS_B_TO_FSB(mp, (xfs_ufsize_t)offset + count);
 251         offset_fsb = XFS_B_TO_FSBT(mp, offset);
 252
 253         error = XFS_BMAPI(mp, NULL, io, offset_fsb,
 254                         (xfs_filblks_t)(end_fsb - offset_fsb),
 255                         bmapi_flags,  NULL, 0, &imap,
 256                         &nimaps, NULL);
 257
 258         if (error)
 259                 goto out;
 260
 261 phase2:
 262         switch (flags & (BMAPI_WRITE|BMAPI_ALLOCATE|BMAPI_UNWRITTEN)) {
 263         case BMAPI_WRITE:
 264                 /* If we found an extent, return it */
 265                 if (nimaps &&
 266                     (imap.br_startblock != HOLESTARTBLOCK) &&
 267                     (imap.br_startblock != DELAYSTARTBLOCK)) {
 268                         xfs_iomap_map_trace(XFS_IOMAP_WRITE_MAP, io,
 269                                         offset, count, iomapp, &imap, flags);
 270                         break;
 271                 }
 272
 273                 if (flags & (BMAPI_DIRECT|BMAPI_MMAP)) {
 274                         error = XFS_IOMAP_WRITE_DIRECT(mp, io, offset,
 275                                         count, flags, &imap, &nimaps, nimaps);
 276                 } else {
 277                         error = XFS_IOMAP_WRITE_DELAY(mp, io, offset, count,
 278                                         flags, &imap, &nimaps);
 279                 }
 280                 if (!error) {
 281                         xfs_iomap_map_trace(XFS_IOMAP_ALLOC_MAP, io,
 282                                         offset, count, iomapp, &imap, flags);
 283                 }
 284                 iomap_flags = IOMAP_NEW;
 285                 break;
 286         case BMAPI_ALLOCATE:
 287                 /* If we found an extent, return it */
 288                 XFS_IUNLOCK(mp, io, lockmode);
 289                 lockmode = 0;
 290
 291                 if (nimaps && !ISNULLSTARTBLOCK(imap.br_startblock)) {
 292                         xfs_iomap_map_trace(XFS_IOMAP_WRITE_MAP, io,
 293                                         offset, count, iomapp, &imap, flags);
 294                         break;
 295                 }
 296
 297                 error = XFS_IOMAP_WRITE_ALLOCATE(mp, io, offset, count,
 298                                                  &imap, &nimaps);
 299                 break;
 300         case BMAPI_UNWRITTEN:
 301                 lockmode = 0;
 302                 error = XFS_IOMAP_WRITE_UNWRITTEN(mp, io, offset, count);
 303                 nimaps = 0;
 304                 break;
 305         }
 306
 307         if (nimaps) {
 308                 *niomaps = xfs_imap_to_bmap(io, offset, &imap,
 309                                             iomapp, nimaps, *niomaps, iomap_flags);
 310         } else if (niomaps) {
 311                 *niomaps = 0;
 312         }
 313
 314 out:
 315         if (lockmode)
 316                 XFS_IUNLOCK(mp, io, lockmode);
 317         return XFS_ERROR(error);
 318 }
 319
 320 STATIC int
 321 xfs_iomap_eof_align_last_fsb(
 322         xfs_mount_t     *mp,
 323         xfs_iocore_t    *io,
 324         xfs_fsize_t     isize,
 325         xfs_extlen_t    extsize,
 326         xfs_fileoff_t   *last_fsb)
 327 {
 328         xfs_fileoff_t   new_last_fsb = 0;
 329         xfs_extlen_t    align;
 330         int             eof, error;
 331
 332         if (io->io_flags & XFS_IOCORE_RT)
 333                 ;
 334         /*
 335          * If mounted with the "-o swalloc" option, roundup the allocation
 336          * request to a stripe width boundary if the file size is >=
 337          * stripe width and we are allocating past the allocation eof.
 338          */
 339         else if (mp->m_swidth && (mp->m_flags & XFS_MOUNT_SWALLOC) &&
 340                 (isize >= XFS_FSB_TO_B(mp, mp->m_swidth)))
 341                 new_last_fsb = roundup_64(*last_fsb, mp->m_swidth);
 342         /*
 343          * Roundup the allocation request to a stripe unit (m_dalign) boundary
 344          * if the file size is >= stripe unit size, and we are allocating past
 345          * the allocation eof.
 346          */
 347         else if (mp->m_dalign && (isize >= XFS_FSB_TO_B(mp, mp->m_dalign)))
 348                 new_last_fsb = roundup_64(*last_fsb, mp->m_dalign);
 349
 350         /*
 351          * Always round up the allocation request to an extent boundary
 352          * (when file on a real-time subvolume or has di_extsize hint).
 353          */
 354         if (extsize) {
 355                 if (new_last_fsb)
 356                         align = roundup_64(new_last_fsb, extsize);
 357                 else
 358                         align = extsize;
 359                 new_last_fsb = roundup_64(*last_fsb, align);
 360         }
 361
 362         if (new_last_fsb) {
 363                 error = XFS_BMAP_EOF(mp, io, new_last_fsb, XFS_DATA_FORK, &eof);
 364                 if (error)
 365                         return error;
 366                 if (eof)
 367                         *last_fsb = new_last_fsb;
 368         }
 369         return 0;
 370 }
 371
 372 STATIC int
 373 xfs_flush_space(
 374         xfs_inode_t     *ip,
 375         int             *fsynced,
 376         int             *ioflags)
 377 {
 378         switch (*fsynced) {
 379         case 0:
 380                 if (ip->i_delayed_blks) {
 381                         xfs_iunlock(ip, XFS_ILOCK_EXCL);
 382                         xfs_flush_inode(ip);
 383                         xfs_ilock(ip, XFS_ILOCK_EXCL);
 384                         *fsynced = 1;
 385                 } else {
 386                         *ioflags |= BMAPI_SYNC;
 387                         *fsynced = 2;
 388                 }
 389                 return 0;
 390         case 1:
 391                 *fsynced = 2;
 392                 *ioflags |= BMAPI_SYNC;
 393                 return 0;
 394         case 2:
 395                 xfs_iunlock(ip, XFS_ILOCK_EXCL);
 396                 xfs_flush_device(ip);
 397                 xfs_ilock(ip, XFS_ILOCK_EXCL);
 398                 *fsynced = 3;
 399                 return 0;
 400         }
 401         return 1;
 402 }
 403
 404 int
 405 xfs_iomap_write_direct(
 406         xfs_inode_t     *ip,
 407         xfs_off_t       offset,
 408         size_t          count,
 409         int             flags,
 410         xfs_bmbt_irec_t *ret_imap,
 411         int             *nmaps,
 412         int             found)
 413 {
 414         xfs_mount_t     *mp = ip->i_mount;
 415         xfs_iocore_t    *io = &ip->i_iocore;
 416         xfs_fileoff_t   offset_fsb;
 417         xfs_fileoff_t   last_fsb;
 418         xfs_filblks_t   count_fsb, resaligned;
 419         xfs_fsblock_t   firstfsb;
 420         xfs_extlen_t    extsz, temp;
 421         xfs_fsize_t     isize;
 422         int             nimaps;
 423         int             bmapi_flag;
 424         int             quota_flag;
 425         int             rt;
 426         xfs_trans_t     *tp;
 427         xfs_bmbt_irec_t imap;
 428         xfs_bmap_free_t free_list;
 429         uint            qblocks, resblks, resrtextents;
 430         int             committed;
 431         int             error;
 432
 433         /*
 434          * Make sure that the dquots are there. This doesn't hold
 435          * the ilock across a disk read.
 436          */
 437         error = XFS_QM_DQATTACH(ip->i_mount, ip, XFS_QMOPT_ILOCKED);
 438         if (error)
 439                 return XFS_ERROR(error);
 440
 441         rt = XFS_IS_REALTIME_INODE(ip);
 442         if (unlikely(rt)) {
 443                 if (!(extsz = ip->i_d.di_extsize))
 444                         extsz = mp->m_sb.sb_rextsize;
 445         } else {
 446                 extsz = ip->i_d.di_extsize;
 447         }
 448
 449         isize = ip->i_d.di_size;
 450         if (io->io_new_size > isize)
 451                 isize = io->io_new_size;
 452
 453         offset_fsb = XFS_B_TO_FSBT(mp, offset);
 454         last_fsb = XFS_B_TO_FSB(mp, ((xfs_ufsize_t)(offset + count)));
 455         if ((offset + count) > isize) {
 456                 error = xfs_iomap_eof_align_last_fsb(mp, io, isize, extsz,
 457                                                         &last_fsb);
 458                 if (error)
 459                         goto error_out;
 460         } else {
 461                 if (found && (ret_imap->br_startblock == HOLESTARTBLOCK))
 462                         last_fsb = MIN(last_fsb, (xfs_fileoff_t)
 463                                         ret_imap->br_blockcount +
 464                                         ret_imap->br_startoff);
 465         }
 466         count_fsb = last_fsb - offset_fsb;
 467         ASSERT(count_fsb > 0);
 468
 469         resaligned = count_fsb;
 470         if (unlikely(extsz)) {
 471                 if ((temp = do_mod(offset_fsb, extsz)))
 472                         resaligned += temp;
 473                 if ((temp = do_mod(resaligned, extsz)))
 474                         resaligned += extsz - temp;
 475         }
 476
 477         if (unlikely(rt)) {
 478                 resrtextents = qblocks = resaligned;
 479                 resrtextents /= mp->m_sb.sb_rextsize;
 480                 resblks = XFS_DIOSTRAT_SPACE_RES(mp, 0);
 481                 quota_flag = XFS_QMOPT_RES_RTBLKS;
 482         } else {
 483                 resrtextents = 0;
 484                 resblks = qblocks = XFS_DIOSTRAT_SPACE_RES(mp, resaligned);
 485                 quota_flag = XFS_QMOPT_RES_REGBLKS;
 486         }
 487
 488         /*
 489          * Allocate and setup the transaction
 490          */
 491         xfs_iunlock(ip, XFS_ILOCK_EXCL);
 492         tp = xfs_trans_alloc(mp, XFS_TRANS_DIOSTRAT);
 493         error = xfs_trans_reserve(tp, resblks,
 494                         XFS_WRITE_LOG_RES(mp), resrtextents,
 495                         XFS_TRANS_PERM_LOG_RES,
 496                         XFS_WRITE_LOG_COUNT);
 497         /*
 498          * Check for running out of space, note: need lock to return
 499          */
 500         if (error)
 501                 xfs_trans_cancel(tp, 0);
 502         xfs_ilock(ip, XFS_ILOCK_EXCL);
 503         if (error)
 504                 goto error_out;
 505
 506         error = XFS_TRANS_RESERVE_QUOTA_NBLKS(mp, tp, ip,
 507                                               qblocks, 0, quota_flag);
 508         if (error)
 509                 goto error1;
 510
 511         xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
 512         xfs_trans_ihold(tp, ip);
 513
 514         bmapi_flag = XFS_BMAPI_WRITE;
 515         if ((flags & BMAPI_DIRECT) && (offset < ip->i_d.di_size || extsz))
 516                 bmapi_flag |= XFS_BMAPI_PREALLOC;
 517
 518         /*
 519          * Issue the xfs_bmapi() call to allocate the blocks
 520          */
 521         XFS_BMAP_INIT(&free_list, &firstfsb);
 522         nimaps = 1;
 523         error = xfs_bmapi(tp, ip, offset_fsb, count_fsb,
 524                 bmapi_flag, &firstfsb, 0, &imap, &nimaps, &free_list);
 525         if (error)
 526                 goto error0;
 527
 528         /*
 529          * Complete the transaction
 530          */
 531         error = xfs_bmap_finish(&tp, &free_list, firstfsb, &committed);
 532         if (error)
 533                 goto error0;
 534         error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES, NULL);
 535         if (error)
 536                 goto error_out;
 537
 538         /*
 539          * Copy any maps to caller's array and return any error.
 540          */
 541         if (nimaps == 0) {
 542                 error = (ENOSPC);
 543                 goto error_out;
 544         }
 545
 546         *ret_imap = imap;
 547         *nmaps = 1;
 548         if ( !(io->io_flags & XFS_IOCORE_RT)  && !ret_imap->br_startblock) {
 549                 cmn_err(CE_PANIC,"Access to block zero:  fs <%s> inode: %lld "
 550                         "start_block : %llx start_off : %llx blkcnt : %llx "
 551                         "extent-state : %x \n",
 552                         (ip->i_mount)->m_fsname,
 553                         (long long)ip->i_ino,
 554                         ret_imap->br_startblock, ret_imap->br_startoff,
 555                         ret_imap->br_blockcount,ret_imap->br_state);
 556         }
 557         return 0;
 558
 559 error0: /* Cancel bmap, unlock inode, unreserve quota blocks, cancel trans */
 560         xfs_bmap_cancel(&free_list);
 561         XFS_TRANS_UNRESERVE_QUOTA_NBLKS(mp, tp, ip, qblocks, 0, quota_flag);
 562
 563 error1: /* Just cancel transaction */
 564         xfs_trans_cancel(tp, XFS_TRANS_RELEASE_LOG_RES | XFS_TRANS_ABORT);
 565         *nmaps = 0;     /* nothing set-up here */
 566
 567 error_out:
 568         return XFS_ERROR(error);
 569 }
 570
 571 /*
 572  * If the caller is doing a write at the end of the file,
 573  * then extend the allocation out to the file system's write
 574  * iosize.  We clean up any extra space left over when the
 575  * file is closed in xfs_inactive().
 576  *
 577  * For sync writes, we are flushing delayed allocate space to
 578  * try to make additional space available for allocation near
 579  * the filesystem full boundary - preallocation hurts in that
 580  * situation, of course.
 581  */
 582 STATIC int
 583 xfs_iomap_eof_want_preallocate(
 584         xfs_mount_t     *mp,
 585         xfs_iocore_t    *io,
 586         xfs_fsize_t     isize,
 587         xfs_off_t       offset,
 588         size_t          count,
 589         int             ioflag,
 590         xfs_bmbt_irec_t *imap,
 591         int             nimaps,
 592         int             *prealloc)
 593 {
 594         xfs_fileoff_t   start_fsb;
 595         xfs_filblks_t   count_fsb;
 596         xfs_fsblock_t   firstblock;
 597         int             n, error, imaps;
 598
 599         *prealloc = 0;
 600         if ((ioflag & BMAPI_SYNC) || (offset + count) <= isize)
 601                 return 0;
 602
 603         /*
 604          * If there are any real blocks past eof, then don't
 605          * do any speculative allocation.
 606          */
 607         start_fsb = XFS_B_TO_FSBT(mp, ((xfs_ufsize_t)(offset + count - 1)));
 608         count_fsb = XFS_B_TO_FSB(mp, (xfs_ufsize_t)XFS_MAXIOFFSET(mp));
 609         while (count_fsb > 0) {
 610                 imaps = nimaps;
 611                 error = XFS_BMAPI(mp, NULL, io, start_fsb, count_fsb,
 612                                   0, &firstblock, 0, imap, &imaps, 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(NULL, ip, 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);
 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                         ret_imap->br_startblock, ret_imap->br_startoff,
 725                         ret_imap->br_blockcount,ret_imap->br_state);
 726         }
 727
 728         *ret_imap = imap[0];
 729         *nmaps = 1;
 730
 731         return 0;
 732 }
 733
 734 /*
 735  * Pass in a delayed allocate extent, convert it to real extents;
 736  * return to the caller the extent we create which maps on top of
 737  * the originating callers request.
 738  *
 739  * Called without a lock on the inode.
 740  */
 741 int
 742 xfs_iomap_write_allocate(
 743         xfs_inode_t     *ip,
 744         xfs_off_t       offset,
 745         size_t          count,
 746         xfs_bmbt_irec_t *map,
 747         int             *retmap)
 748 {
 749         xfs_mount_t     *mp = ip->i_mount;
 750         xfs_iocore_t    *io = &ip->i_iocore;
 751         xfs_fileoff_t   offset_fsb, last_block;
 752         xfs_fileoff_t   end_fsb, map_start_fsb;
 753         xfs_fsblock_t   first_block;
 754         xfs_bmap_free_t free_list;
 755         xfs_filblks_t   count_fsb;
 756         xfs_bmbt_irec_t imap[XFS_STRAT_WRITE_IMAPS];
 757         xfs_trans_t     *tp;
 758         int             i, nimaps, committed;
 759         int             error = 0;
 760         int             nres;
 761
 762         *retmap = 0;
 763
 764         /*
 765          * Make sure that the dquots are there.
 766          */
 767         if ((error = XFS_QM_DQATTACH(mp, ip, 0)))
 768                 return XFS_ERROR(error);
 769
 770         offset_fsb = XFS_B_TO_FSBT(mp, offset);
 771         count_fsb = map->br_blockcount;
 772         map_start_fsb = map->br_startoff;
 773
 774         XFS_STATS_ADD(xs_xstrat_bytes, XFS_FSB_TO_B(mp, count_fsb));
 775
 776         while (count_fsb != 0) {
 777                 /*
 778                  * Set up a transaction with which to allocate the
 779                  * backing store for the file.  Do allocations in a
 780                  * loop until we get some space in the range we are
 781                  * interested in.  The other space that might be allocated
 782                  * is in the delayed allocation extent on which we sit
 783                  * but before our buffer starts.
 784                  */
 785
 786                 nimaps = 0;
 787                 while (nimaps == 0) {
 788                         tp = xfs_trans_alloc(mp, XFS_TRANS_STRAT_WRITE);
 789                         nres = XFS_EXTENTADD_SPACE_RES(mp, XFS_DATA_FORK);
 790                         error = xfs_trans_reserve(tp, nres,
 791                                         XFS_WRITE_LOG_RES(mp),
 792                                         0, XFS_TRANS_PERM_LOG_RES,
 793                                         XFS_WRITE_LOG_COUNT);
 794                         if (error == ENOSPC) {
 795                                 error = xfs_trans_reserve(tp, 0,
 796                                                 XFS_WRITE_LOG_RES(mp),
 797                                                 0,
 798                                                 XFS_TRANS_PERM_LOG_RES,
 799                                                 XFS_WRITE_LOG_COUNT);
 800                         }
 801                         if (error) {
 802                                 xfs_trans_cancel(tp, 0);
 803                                 return XFS_ERROR(error);
 804                         }
 805                         xfs_ilock(ip, XFS_ILOCK_EXCL);
 806                         xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
 807                         xfs_trans_ihold(tp, ip);
 808
 809                         XFS_BMAP_INIT(&free_list, &first_block);
 810
 811                         nimaps = XFS_STRAT_WRITE_IMAPS;
 812                         /*
 813                          * Ensure we don't go beyond eof - it is possible
 814                          * the extents changed since we did the read call,
 815                          * we dropped the ilock in the interim.
 816                          */
 817
 818                         end_fsb = XFS_B_TO_FSB(mp, ip->i_d.di_size);
 819                         xfs_bmap_last_offset(NULL, ip, &last_block,
 820                                 XFS_DATA_FORK);
 821                         last_block = XFS_FILEOFF_MAX(last_block, end_fsb);
 822                         if ((map_start_fsb + count_fsb) > last_block) {
 823                                 count_fsb = last_block - map_start_fsb;
 824                                 if (count_fsb == 0) {
 825                                         error = EAGAIN;
 826                                         goto trans_cancel;
 827                                 }
 828                         }
 829
 830                         /* Go get the actual blocks */
 831                         error = xfs_bmapi(tp, ip, map_start_fsb, count_fsb,
 832                                         XFS_BMAPI_WRITE, &first_block, 1,
 833                                         imap, &nimaps, &free_list);
 834                         if (error)
 835                                 goto trans_cancel;
 836
 837                         error = xfs_bmap_finish(&tp, &free_list,
 838                                         first_block, &committed);
 839                         if (error)
 840                                 goto trans_cancel;
 841
 842                         error = xfs_trans_commit(tp,
 843                                         XFS_TRANS_RELEASE_LOG_RES, NULL);
 844                         if (error)
 845                                 goto error0;
 846
 847                         xfs_iunlock(ip, XFS_ILOCK_EXCL);
 848                 }
 849
 850                 /*
 851                  * See if we were able to allocate an extent that
 852                  * covers at least part of the callers request
 853                  */
 854
 855                 for (i = 0; i < nimaps; i++) {
 856                         if ( !(io->io_flags & XFS_IOCORE_RT)  &&
 857                                 !imap[i].br_startblock) {
 858                                 cmn_err(CE_PANIC,"Access to block zero:  "
 859                                         "fs <%s> inode: %lld "
 860                                         "start_block : %llx start_off : %llx "
 861                                         "blkcnt : %llx extent-state : %x \n",
 862                                         (ip->i_mount)->m_fsname,
 863                                         (long long)ip->i_ino,
 864                                         imap[i].br_startblock,
 865                                         imap[i].br_startoff,
 866                                         imap[i].br_blockcount,imap[i].br_state);
 867                         }
 868                         if ((offset_fsb >= imap[i].br_startoff) &&
 869                             (offset_fsb < (imap[i].br_startoff +
 870                                            imap[i].br_blockcount))) {
 871                                 *map = imap[i];
 872                                 *retmap = 1;
 873                                 XFS_STATS_INC(xs_xstrat_quick);
 874                                 return 0;
 875                         }
 876                         count_fsb -= imap[i].br_blockcount;
 877                 }
 878
 879                 /* So far we have not mapped the requested part of the
 880                  * file, just surrounding data, try again.
 881                  */
 882                 nimaps--;
 883                 map_start_fsb = imap[nimaps].br_startoff +
 884                                 imap[nimaps].br_blockcount;
 885         }
 886
 887 trans_cancel:
 888         xfs_bmap_cancel(&free_list);
 889         xfs_trans_cancel(tp, XFS_TRANS_RELEASE_LOG_RES | XFS_TRANS_ABORT);
 890 error0:
 891         xfs_iunlock(ip, XFS_ILOCK_EXCL);
 892         return XFS_ERROR(error);
 893 }
 894
 895 int
 896 xfs_iomap_write_unwritten(
 897         xfs_inode_t     *ip,
 898         xfs_off_t       offset,
 899         size_t          count)
 900 {
 901         xfs_mount_t     *mp = ip->i_mount;
 902         xfs_iocore_t    *io = &ip->i_iocore;
 903         xfs_fileoff_t   offset_fsb;
 904         xfs_filblks_t   count_fsb;
 905         xfs_filblks_t   numblks_fsb;
 906         xfs_fsblock_t   firstfsb;
 907         int             nimaps;
 908         xfs_trans_t     *tp;
 909         xfs_bmbt_irec_t imap;
 910         xfs_bmap_free_t free_list;
 911         uint            resblks;
 912         int             committed;
 913         int             error;
 914
 915         xfs_iomap_enter_trace(XFS_IOMAP_UNWRITTEN,
 916                                 &ip->i_iocore, offset, count);
 917
 918         offset_fsb = XFS_B_TO_FSBT(mp, offset);
 919         count_fsb = XFS_B_TO_FSB(mp, (xfs_ufsize_t)offset + count);
 920         count_fsb = (xfs_filblks_t)(count_fsb - offset_fsb);
 921
 922         resblks = XFS_DIOSTRAT_SPACE_RES(mp, 0) << 1;
 923
 924         do {
 925                 /*
 926                  * set up a transaction to convert the range of extents
 927                  * from unwritten to real. Do allocations in a loop until
 928                  * we have covered the range passed in.
 929                  */
 930
 931                 tp = xfs_trans_alloc(mp, XFS_TRANS_STRAT_WRITE);
 932                 error = xfs_trans_reserve(tp, resblks,
 933                                 XFS_WRITE_LOG_RES(mp), 0,
 934                                 XFS_TRANS_PERM_LOG_RES,
 935                                 XFS_WRITE_LOG_COUNT);
 936                 if (error) {
 937                         xfs_trans_cancel(tp, 0);
 938                         goto error0;
 939                 }
 940
 941                 xfs_ilock(ip, XFS_ILOCK_EXCL);
 942                 xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
 943                 xfs_trans_ihold(tp, ip);
 944
 945                 /*
 946                  * Modify the unwritten extent state of the buffer.
 947                  */
 948                 XFS_BMAP_INIT(&free_list, &firstfsb);
 949                 nimaps = 1;
 950                 error = xfs_bmapi(tp, ip, offset_fsb, count_fsb,
 951                                   XFS_BMAPI_WRITE|XFS_BMAPI_CONVERT, &firstfsb,
 952                                   1, &imap, &nimaps, &free_list);
 953                 if (error)
 954                         goto error_on_bmapi_transaction;
 955
 956                 error = xfs_bmap_finish(&(tp), &(free_list),
 957                                 firstfsb, &committed);
 958                 if (error)
 959                         goto error_on_bmapi_transaction;
 960
 961                 error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES, NULL);
 962                 xfs_iunlock(ip, XFS_ILOCK_EXCL);
 963                 if (error)
 964                         goto error0;
 965
 966                 if ( !(io->io_flags & XFS_IOCORE_RT)  && !imap.br_startblock) {
 967                         cmn_err(CE_PANIC,"Access to block zero:  fs <%s> "
 968                                 "inode: %lld start_block : %llx start_off : "
 969                                 "%llx blkcnt : %llx extent-state : %x \n",
 970                                 (ip->i_mount)->m_fsname,
 971                                 (long long)ip->i_ino,
 972                                 imap.br_startblock,imap.br_startoff,
 973                                 imap.br_blockcount,imap.br_state);
 974                 }
 975
 976                 if ((numblks_fsb = imap.br_blockcount) == 0) {
 977                         /*
 978                          * The numblks_fsb value should always get
 979                          * smaller, otherwise the loop is stuck.
 980                          */
 981                         ASSERT(imap.br_blockcount);
 982                         break;
 983                 }
 984                 offset_fsb += numblks_fsb;
 985                 count_fsb -= numblks_fsb;
 986         } while (count_fsb > 0);
 987
 988         return 0;
 989
 990 error_on_bmapi_transaction:
 991         xfs_bmap_cancel(&free_list);
 992         xfs_trans_cancel(tp, (XFS_TRANS_RELEASE_LOG_RES | XFS_TRANS_ABORT));
 993         xfs_iunlock(ip, XFS_ILOCK_EXCL);
 994 error0:
 995         return XFS_ERROR(error);
 996 }