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   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 && (imap.br_startblock != HOLESTARTBLOCK)) {
 282                         xfs_iomap_map_trace(XFS_IOMAP_WRITE_MAP, io,
 283                                         offset, count, iomapp, &imap, flags);
 284                         break;
 285                 }
 286
 287                 if (flags & (BMAPI_DIRECT|BMAPI_MMAP)) {
 288                         error = XFS_IOMAP_WRITE_DIRECT(mp, io, offset,
 289                                         count, flags, &imap, &nimaps, nimaps);
 290                 } else {
 291                         error = XFS_IOMAP_WRITE_DELAY(mp, io, offset, count,
 292                                         flags, &imap, &nimaps);
 293                 }
 294                 if (!error) {
 295                         xfs_iomap_map_trace(XFS_IOMAP_ALLOC_MAP, io,
 296                                         offset, count, iomapp, &imap, flags);
 297                 }
 298                 iomap_flags = IOMAP_NEW;
 299                 break;
 300         case BMAPI_ALLOCATE:
 301                 /* If we found an extent, return it */
 302                 XFS_IUNLOCK(mp, io, lockmode);
 303                 lockmode = 0;
 304
 305                 if (nimaps && !ISNULLSTARTBLOCK(imap.br_startblock)) {
 306                         xfs_iomap_map_trace(XFS_IOMAP_WRITE_MAP, io,
 307                                         offset, count, iomapp, &imap, flags);
 308                         break;
 309                 }
 310
 311                 error = XFS_IOMAP_WRITE_ALLOCATE(mp, io, offset, count,
 312                                                  &imap, &nimaps);
 313                 break;
 314         case BMAPI_UNWRITTEN:
 315                 lockmode = 0;
 316                 error = XFS_IOMAP_WRITE_UNWRITTEN(mp, io, offset, count);
 317                 nimaps = 0;
 318                 break;
 319         }
 320
 321         if (nimaps) {
 322                 *niomaps = xfs_imap_to_bmap(io, offset, &imap,
 323                                             iomapp, nimaps, *niomaps, iomap_flags);
 324         } else if (niomaps) {
 325                 *niomaps = 0;
 326         }
 327
 328 out:
 329         if (lockmode)
 330                 XFS_IUNLOCK(mp, io, lockmode);
 331         return XFS_ERROR(error);
 332 }
 333
 334 STATIC int
 335 xfs_flush_space(
 336         xfs_inode_t     *ip,
 337         int             *fsynced,
 338         int             *ioflags)
 339 {
 340         switch (*fsynced) {
 341         case 0:
 342                 if (ip->i_delayed_blks) {
 343                         xfs_iunlock(ip, XFS_ILOCK_EXCL);
 344                         xfs_flush_inode(ip);
 345                         xfs_ilock(ip, XFS_ILOCK_EXCL);
 346                         *fsynced = 1;
 347                 } else {
 348                         *ioflags |= BMAPI_SYNC;
 349                         *fsynced = 2;
 350                 }
 351                 return 0;
 352         case 1:
 353                 *fsynced = 2;
 354                 *ioflags |= BMAPI_SYNC;
 355                 return 0;
 356         case 2:
 357                 xfs_iunlock(ip, XFS_ILOCK_EXCL);
 358                 xfs_flush_device(ip);
 359                 xfs_ilock(ip, XFS_ILOCK_EXCL);
 360                 *fsynced = 3;
 361                 return 0;
 362         }
 363         return 1;
 364 }
 365
 366 int
 367 xfs_iomap_write_direct(
 368         xfs_inode_t     *ip,
 369         xfs_off_t       offset,
 370         size_t          count,
 371         int             flags,
 372         xfs_bmbt_irec_t *ret_imap,
 373         int             *nmaps,
 374         int             found)
 375 {
 376         xfs_mount_t     *mp = ip->i_mount;
 377         xfs_iocore_t    *io = &ip->i_iocore;
 378         xfs_fileoff_t   offset_fsb;
 379         xfs_fileoff_t   last_fsb;
 380         xfs_filblks_t   count_fsb;
 381         xfs_fsize_t     isize;
 382         xfs_fsblock_t   firstfsb;
 383         int             nimaps, maps;
 384         int             error;
 385         int             bmapi_flag;
 386         int             rt;
 387         xfs_trans_t     *tp;
 388         xfs_bmbt_irec_t imap[XFS_WRITE_IMAPS], *imapp;
 389         xfs_bmap_free_t free_list;
 390         int             aeof;
 391         xfs_filblks_t   datablocks;
 392         int             committed;
 393         int             numrtextents;
 394         uint            resblks;
 395
 396         /*
 397          * Make sure that the dquots are there. This doesn't hold
 398          * the ilock across a disk read.
 399          */
 400         error = XFS_QM_DQATTACH(ip->i_mount, ip, XFS_QMOPT_ILOCKED);
 401         if (error)
 402                 return XFS_ERROR(error);
 403
 404         maps = min(XFS_WRITE_IMAPS, *nmaps);
 405         nimaps = maps;
 406
 407         isize = ip->i_d.di_size;
 408         aeof = (offset + count) > isize;
 409
 410         if (io->io_new_size > isize)
 411                 isize = io->io_new_size;
 412
 413         offset_fsb = XFS_B_TO_FSBT(mp, offset);
 414         last_fsb = XFS_B_TO_FSB(mp, ((xfs_ufsize_t)(offset + count)));
 415         count_fsb = last_fsb - offset_fsb;
 416         if (found && (ret_imap->br_startblock == HOLESTARTBLOCK)) {
 417                 xfs_fileoff_t   map_last_fsb;
 418
 419                 map_last_fsb = ret_imap->br_blockcount + ret_imap->br_startoff;
 420
 421                 if (map_last_fsb < last_fsb) {
 422                         last_fsb = map_last_fsb;
 423                         count_fsb = last_fsb - offset_fsb;
 424                 }
 425                 ASSERT(count_fsb > 0);
 426         }
 427
 428         /*
 429          * determine if reserving space on
 430          * the data or realtime partition.
 431          */
 432         if ((rt = XFS_IS_REALTIME_INODE(ip))) {
 433                 int     sbrtextsize, iprtextsize;
 434
 435                 sbrtextsize = mp->m_sb.sb_rextsize;
 436                 iprtextsize =
 437                         ip->i_d.di_extsize ? ip->i_d.di_extsize : sbrtextsize;
 438                 numrtextents = (count_fsb + iprtextsize - 1);
 439                 do_div(numrtextents, sbrtextsize);
 440                 datablocks = 0;
 441         } else {
 442                 datablocks = count_fsb;
 443                 numrtextents = 0;
 444         }
 445
 446         /*
 447          * allocate and setup the transaction
 448          */
 449         xfs_iunlock(ip, XFS_ILOCK_EXCL);
 450         tp = xfs_trans_alloc(mp, XFS_TRANS_DIOSTRAT);
 451
 452         resblks = XFS_DIOSTRAT_SPACE_RES(mp, datablocks);
 453
 454         error = xfs_trans_reserve(tp, resblks,
 455                         XFS_WRITE_LOG_RES(mp), numrtextents,
 456                         XFS_TRANS_PERM_LOG_RES,
 457                         XFS_WRITE_LOG_COUNT);
 458
 459         /*
 460          * check for running out of space
 461          */
 462         if (error)
 463                 /*
 464                  * Free the transaction structure.
 465                  */
 466                 xfs_trans_cancel(tp, 0);
 467
 468         xfs_ilock(ip, XFS_ILOCK_EXCL);
 469
 470         if (error)
 471                 goto error_out; /* Don't return in above if .. trans ..,
 472                                         need lock to return */
 473
 474         if (XFS_TRANS_RESERVE_BLKQUOTA(mp, tp, ip, resblks)) {
 475                 error = (EDQUOT);
 476                 goto error1;
 477         }
 478         nimaps = 1;
 479
 480         bmapi_flag = XFS_BMAPI_WRITE;
 481         xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
 482         xfs_trans_ihold(tp, ip);
 483
 484         if (!(flags & BMAPI_MMAP) && (offset < ip->i_d.di_size || rt))
 485                 bmapi_flag |= XFS_BMAPI_PREALLOC;
 486
 487         /*
 488          * issue the bmapi() call to allocate the blocks
 489          */
 490         XFS_BMAP_INIT(&free_list, &firstfsb);
 491         imapp = &imap[0];
 492         error = xfs_bmapi(tp, ip, offset_fsb, count_fsb,
 493                 bmapi_flag, &firstfsb, 0, imapp, &nimaps, &free_list);
 494         if (error) {
 495                 goto error0;
 496         }
 497
 498         /*
 499          * complete the transaction
 500          */
 501
 502         error = xfs_bmap_finish(&tp, &free_list, firstfsb, &committed);
 503         if (error) {
 504                 goto error0;
 505         }
 506
 507         error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES, NULL);
 508         if (error) {
 509                 goto error_out;
 510         }
 511
 512         /* copy any maps to caller's array and return any error. */
 513         if (nimaps == 0) {
 514                 error = (ENOSPC);
 515                 goto error_out;
 516         }
 517
 518         *ret_imap = imap[0];
 519         *nmaps = 1;
 520         if ( !(io->io_flags & XFS_IOCORE_RT)  && !ret_imap->br_startblock) {
 521                 cmn_err(CE_PANIC,"Access to block zero:  fs <%s> inode: %lld "
 522                         "start_block : %llx start_off : %llx blkcnt : %llx "
 523                         "extent-state : %x \n",
 524                         (ip->i_mount)->m_fsname,
 525                         (long long)ip->i_ino,
 526                         ret_imap->br_startblock, ret_imap->br_startoff,
 527                         ret_imap->br_blockcount,ret_imap->br_state);
 528         }
 529         return 0;
 530
 531  error0:        /* Cancel bmap, unlock inode, and cancel trans */
 532         xfs_bmap_cancel(&free_list);
 533
 534  error1:        /* Just cancel transaction */
 535         xfs_trans_cancel(tp, XFS_TRANS_RELEASE_LOG_RES | XFS_TRANS_ABORT);
 536         *nmaps = 0;     /* nothing set-up here */
 537
 538 error_out:
 539         return XFS_ERROR(error);
 540 }
 541
 542 int
 543 xfs_iomap_write_delay(
 544         xfs_inode_t     *ip,
 545         xfs_off_t       offset,
 546         size_t          count,
 547         int             ioflag,
 548         xfs_bmbt_irec_t *ret_imap,
 549         int             *nmaps)
 550 {
 551         xfs_mount_t     *mp = ip->i_mount;
 552         xfs_iocore_t    *io = &ip->i_iocore;
 553         xfs_fileoff_t   offset_fsb;
 554         xfs_fileoff_t   last_fsb;
 555         xfs_fsize_t     isize;
 556         xfs_fsblock_t   firstblock;
 557         int             nimaps;
 558         int             error;
 559         xfs_bmbt_irec_t imap[XFS_WRITE_IMAPS];
 560         int             aeof;
 561         int             fsynced = 0;
 562
 563         ASSERT(ismrlocked(&ip->i_lock, MR_UPDATE) != 0);
 564
 565         /*
 566          * Make sure that the dquots are there. This doesn't hold
 567          * the ilock across a disk read.
 568          */
 569
 570         error = XFS_QM_DQATTACH(mp, ip, XFS_QMOPT_ILOCKED);
 571         if (error)
 572                 return XFS_ERROR(error);
 573
 574 retry:
 575         isize = ip->i_d.di_size;
 576         if (io->io_new_size > isize) {
 577                 isize = io->io_new_size;
 578         }
 579
 580         aeof = 0;
 581         offset_fsb = XFS_B_TO_FSBT(mp, offset);
 582         last_fsb = XFS_B_TO_FSB(mp, ((xfs_ufsize_t)(offset + count)));
 583         /*
 584          * If the caller is doing a write at the end of the file,
 585          * then extend the allocation (and the buffer used for the write)
 586          * out to the file system's write iosize.  We clean up any extra
 587          * space left over when the file is closed in xfs_inactive().
 588          *
 589          * For sync writes, we are flushing delayed allocate space to
 590          * try to make additional space available for allocation near
 591          * the filesystem full boundary - preallocation hurts in that
 592          * situation, of course.
 593          */
 594         if (!(ioflag & BMAPI_SYNC) && ((offset + count) > ip->i_d.di_size)) {
 595                 xfs_off_t       aligned_offset;
 596                 xfs_filblks_t   count_fsb;
 597                 unsigned int    iosize;
 598                 xfs_fileoff_t   ioalign;
 599                 int             n;
 600                 xfs_fileoff_t   start_fsb;
 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,
 607                                         ((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                         nimaps = XFS_WRITE_IMAPS;
 611                         error = XFS_BMAPI(mp, NULL, io, start_fsb, count_fsb,
 612                                         0, &firstblock, 0, imap, &nimaps, NULL);
 613                         if (error) {
 614                                 return error;
 615                         }
 616                         for (n = 0; n < nimaps; n++) {
 617                                 if ( !(io->io_flags & XFS_IOCORE_RT)  &&
 618                                         !imap[n].br_startblock) {
 619                                         cmn_err(CE_PANIC,"Access to block "
 620                                                 "zero:  fs <%s> inode: %lld "
 621                                                 "start_block : %llx start_off "
 622                                                 ": %llx blkcnt : %llx "
 623                                                 "extent-state : %x \n",
 624                                                 (ip->i_mount)->m_fsname,
 625                                                 (long long)ip->i_ino,
 626                                                 imap[n].br_startblock,
 627                                                 imap[n].br_startoff,
 628                                                 imap[n].br_blockcount,
 629                                                 imap[n].br_state);
 630                                 }
 631                                 if ((imap[n].br_startblock != HOLESTARTBLOCK) &&
 632                                     (imap[n].br_startblock != DELAYSTARTBLOCK)) {
 633                                         goto write_map;
 634                                 }
 635                                 start_fsb += imap[n].br_blockcount;
 636                                 count_fsb -= imap[n].br_blockcount;
 637                         }
 638                 }
 639                 iosize = mp->m_writeio_blocks;
 640                 aligned_offset = XFS_WRITEIO_ALIGN(mp, (offset + count - 1));
 641                 ioalign = XFS_B_TO_FSBT(mp, aligned_offset);
 642                 last_fsb = ioalign + iosize;
 643                 aeof = 1;
 644         }
 645 write_map:
 646         nimaps = XFS_WRITE_IMAPS;
 647         firstblock = NULLFSBLOCK;
 648
 649         /*
 650          * If mounted with the "-o swalloc" option, roundup the allocation
 651          * request to a stripe width boundary if the file size is >=
 652          * stripe width and we are allocating past the allocation eof.
 653          */
 654         if (!(io->io_flags & XFS_IOCORE_RT) && mp->m_swidth
 655             && (mp->m_flags & XFS_MOUNT_SWALLOC)
 656             && (isize >= XFS_FSB_TO_B(mp, mp->m_swidth)) && aeof) {
 657                 int eof;
 658                 xfs_fileoff_t new_last_fsb;
 659
 660                 new_last_fsb = roundup_64(last_fsb, mp->m_swidth);
 661                 error = xfs_bmap_eof(ip, new_last_fsb, XFS_DATA_FORK, &eof);
 662                 if (error) {
 663                         return error;
 664                 }
 665                 if (eof) {
 666                         last_fsb = new_last_fsb;
 667                 }
 668         /*
 669          * Roundup the allocation request to a stripe unit (m_dalign) boundary
 670          * if the file size is >= stripe unit size, and we are allocating past
 671          * the allocation eof.
 672          */
 673         } else if (!(io->io_flags & XFS_IOCORE_RT) && mp->m_dalign &&
 674                    (isize >= XFS_FSB_TO_B(mp, mp->m_dalign)) && aeof) {
 675                 int eof;
 676                 xfs_fileoff_t new_last_fsb;
 677                 new_last_fsb = roundup_64(last_fsb, mp->m_dalign);
 678                 error = xfs_bmap_eof(ip, new_last_fsb, XFS_DATA_FORK, &eof);
 679                 if (error) {
 680                         return error;
 681                 }
 682                 if (eof) {
 683                         last_fsb = new_last_fsb;
 684                 }
 685         /*
 686          * Round up the allocation request to a real-time extent boundary
 687          * if the file is on the real-time subvolume.
 688          */
 689         } else if (io->io_flags & XFS_IOCORE_RT && aeof) {
 690                 int eof;
 691                 xfs_fileoff_t new_last_fsb;
 692
 693                 new_last_fsb = roundup_64(last_fsb, mp->m_sb.sb_rextsize);
 694                 error = XFS_BMAP_EOF(mp, io, new_last_fsb, XFS_DATA_FORK, &eof);
 695                 if (error) {
 696                         return error;
 697                 }
 698                 if (eof)
 699                         last_fsb = new_last_fsb;
 700         }
 701         error = xfs_bmapi(NULL, ip, offset_fsb,
 702                           (xfs_filblks_t)(last_fsb - offset_fsb),
 703                           XFS_BMAPI_DELAY | XFS_BMAPI_WRITE |
 704                           XFS_BMAPI_ENTIRE, &firstblock, 1, imap,
 705                           &nimaps, NULL);
 706         /*
 707          * This can be EDQUOT, if nimaps == 0
 708          */
 709         if (error && (error != ENOSPC)) {
 710                 return XFS_ERROR(error);
 711         }
 712         /*
 713          * If bmapi returned us nothing, and if we didn't get back EDQUOT,
 714          * then we must have run out of space.
 715          */
 716         if (nimaps == 0) {
 717                 xfs_iomap_enter_trace(XFS_IOMAP_WRITE_NOSPACE,
 718                                         io, offset, count);
 719                 if (xfs_flush_space(ip, &fsynced, &ioflag))
 720                         return XFS_ERROR(ENOSPC);
 721
 722                 error = 0;
 723                 goto retry;
 724         }
 725
 726         *ret_imap = imap[0];
 727         *nmaps = 1;
 728         if ( !(io->io_flags & XFS_IOCORE_RT)  && !ret_imap->br_startblock) {
 729                 cmn_err(CE_PANIC,"Access to block zero:  fs <%s> inode: %lld "
 730                         "start_block : %llx start_off : %llx blkcnt : %llx "
 731                         "extent-state : %x \n",
 732                         (ip->i_mount)->m_fsname,
 733                         (long long)ip->i_ino,
 734                         ret_imap->br_startblock, ret_imap->br_startoff,
 735                         ret_imap->br_blockcount,ret_imap->br_state);
 736         }
 737         return 0;
 738 }
 739
 740 /*
 741  * Pass in a delayed allocate extent, convert it to real extents;
 742  * return to the caller the extent we create which maps on top of
 743  * the originating callers request.
 744  *
 745  * Called without a lock on the inode.
 746  */
 747 int
 748 xfs_iomap_write_allocate(
 749         xfs_inode_t     *ip,
 750         xfs_off_t       offset,
 751         size_t          count,
 752         xfs_bmbt_irec_t *map,
 753         int             *retmap)
 754 {
 755         xfs_mount_t     *mp = ip->i_mount;
 756         xfs_iocore_t    *io = &ip->i_iocore;
 757         xfs_fileoff_t   offset_fsb, last_block;
 758         xfs_fileoff_t   end_fsb, map_start_fsb;
 759         xfs_fsblock_t   first_block;
 760         xfs_bmap_free_t free_list;
 761         xfs_filblks_t   count_fsb;
 762         xfs_bmbt_irec_t imap[XFS_STRAT_WRITE_IMAPS];
 763         xfs_trans_t     *tp;
 764         int             i, nimaps, committed;
 765         int             error = 0;
 766         int             nres;
 767
 768         *retmap = 0;
 769
 770         /*
 771          * Make sure that the dquots are there.
 772          */
 773         if ((error = XFS_QM_DQATTACH(mp, ip, 0)))
 774                 return XFS_ERROR(error);
 775
 776         offset_fsb = XFS_B_TO_FSBT(mp, offset);
 777         count_fsb = map->br_blockcount;
 778         map_start_fsb = map->br_startoff;
 779
 780         XFS_STATS_ADD(xs_xstrat_bytes, XFS_FSB_TO_B(mp, count_fsb));
 781
 782         while (count_fsb != 0) {
 783                 /*
 784                  * Set up a transaction with which to allocate the
 785                  * backing store for the file.  Do allocations in a
 786                  * loop until we get some space in the range we are
 787                  * interested in.  The other space that might be allocated
 788                  * is in the delayed allocation extent on which we sit
 789                  * but before our buffer starts.
 790                  */
 791
 792                 nimaps = 0;
 793                 while (nimaps == 0) {
 794                         tp = xfs_trans_alloc(mp, XFS_TRANS_STRAT_WRITE);
 795                         nres = XFS_EXTENTADD_SPACE_RES(mp, XFS_DATA_FORK);
 796                         error = xfs_trans_reserve(tp, nres,
 797                                         XFS_WRITE_LOG_RES(mp),
 798                                         0, XFS_TRANS_PERM_LOG_RES,
 799                                         XFS_WRITE_LOG_COUNT);
 800                         if (error == ENOSPC) {
 801                                 error = xfs_trans_reserve(tp, 0,
 802                                                 XFS_WRITE_LOG_RES(mp),
 803                                                 0,
 804                                                 XFS_TRANS_PERM_LOG_RES,
 805                                                 XFS_WRITE_LOG_COUNT);
 806                         }
 807                         if (error) {
 808                                 xfs_trans_cancel(tp, 0);
 809                                 return XFS_ERROR(error);
 810                         }
 811                         xfs_ilock(ip, XFS_ILOCK_EXCL);
 812                         xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
 813                         xfs_trans_ihold(tp, ip);
 814
 815                         XFS_BMAP_INIT(&free_list, &first_block);
 816
 817                         nimaps = XFS_STRAT_WRITE_IMAPS;
 818                         /*
 819                          * Ensure we don't go beyond eof - it is possible
 820                          * the extents changed since we did the read call,
 821                          * we dropped the ilock in the interim.
 822                          */
 823
 824                         end_fsb = XFS_B_TO_FSB(mp, ip->i_d.di_size);
 825                         xfs_bmap_last_offset(NULL, ip, &last_block,
 826                                 XFS_DATA_FORK);
 827                         last_block = XFS_FILEOFF_MAX(last_block, end_fsb);
 828                         if ((map_start_fsb + count_fsb) > last_block) {
 829                                 count_fsb = last_block - map_start_fsb;
 830                                 if (count_fsb == 0) {
 831                                         error = EAGAIN;
 832                                         goto trans_cancel;
 833                                 }
 834                         }
 835
 836                         /* Go get the actual blocks */
 837                         error = xfs_bmapi(tp, ip, map_start_fsb, count_fsb,
 838                                         XFS_BMAPI_WRITE, &first_block, 1,
 839                                         imap, &nimaps, &free_list);
 840                         if (error)
 841                                 goto trans_cancel;
 842
 843                         error = xfs_bmap_finish(&tp, &free_list,
 844                                         first_block, &committed);
 845                         if (error)
 846                                 goto trans_cancel;
 847
 848                         error = xfs_trans_commit(tp,
 849                                         XFS_TRANS_RELEASE_LOG_RES, NULL);
 850                         if (error)
 851                                 goto error0;
 852
 853                         xfs_iunlock(ip, XFS_ILOCK_EXCL);
 854                 }
 855
 856                 /*
 857                  * See if we were able to allocate an extent that
 858                  * covers at least part of the callers request
 859                  */
 860
 861                 for (i = 0; i < nimaps; i++) {
 862                         if ( !(io->io_flags & XFS_IOCORE_RT)  &&
 863                                 !imap[i].br_startblock) {
 864                                 cmn_err(CE_PANIC,"Access to block zero:  "
 865                                         "fs <%s> inode: %lld "
 866                                         "start_block : %llx start_off : %llx "
 867                                         "blkcnt : %llx extent-state : %x \n",
 868                                         (ip->i_mount)->m_fsname,
 869                                         (long long)ip->i_ino,
 870                                         imap[i].br_startblock,
 871                                         imap[i].br_startoff,
 872                                         imap[i].br_blockcount,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_trans_t     *tp;
 910         xfs_fileoff_t   offset_fsb;
 911         xfs_filblks_t   count_fsb;
 912         xfs_filblks_t   numblks_fsb;
 913         xfs_bmbt_irec_t imap;
 914         int             committed;
 915         int             error;
 916         int             nres;
 917         int             nimaps;
 918         xfs_fsblock_t   firstfsb;
 919         xfs_bmap_free_t free_list;
 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         do {
 929                 nres = XFS_DIOSTRAT_SPACE_RES(mp, 0);
 930
 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, nres,
 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(tp, ip, offset_fsb, count_fsb,
 957                                   XFS_BMAPI_WRITE, &firstfsb,
 958                                   1, &imap, &nimaps, &free_list);
 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                                 imap.br_startblock,imap.br_startoff,
 979                                 imap.br_blockcount,imap.br_state);
 980                 }
 981
 982                 if ((numblks_fsb = imap.br_blockcount) == 0) {
 983                         /*
 984                          * The numblks_fsb value should always get
 985                          * smaller, otherwise the loop is stuck.
 986                          */
 987                         ASSERT(imap.br_blockcount);
 988                         break;
 989                 }
 990                 offset_fsb += numblks_fsb;
 991                 count_fsb -= numblks_fsb;
 992         } while (count_fsb > 0);
 993
 994         return 0;
 995
 996 error_on_bmapi_transaction:
 997         xfs_bmap_cancel(&free_list);
 998         xfs_trans_cancel(tp, (XFS_TRANS_RELEASE_LOG_RES | XFS_TRANS_ABORT));
 999         xfs_iunlock(ip, XFS_ILOCK_EXCL);
1000 error0:
1001         return XFS_ERROR(error);
1002 }