fs/xfs/libxfs/xfs_bmap.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (c) 2000-2006 Silicon Graphics, Inc.
   4  * All Rights Reserved.
   5  */
   6 #include "xfs.h"
   7 #include "xfs_fs.h"
   8 #include "xfs_shared.h"
   9 #include "xfs_format.h"
  10 #include "xfs_log_format.h"
  11 #include "xfs_trans_resv.h"
  12 #include "xfs_bit.h"
  13 #include "xfs_sb.h"
  14 #include "xfs_mount.h"
  15 #include "xfs_defer.h"
  16 #include "xfs_dir2.h"
  17 #include "xfs_inode.h"
  18 #include "xfs_btree.h"
  19 #include "xfs_trans.h"
  20 #include "xfs_alloc.h"
  21 #include "xfs_bmap.h"
  22 #include "xfs_bmap_util.h"
  23 #include "xfs_bmap_btree.h"
  24 #include "xfs_rtalloc.h"
  25 #include "xfs_errortag.h"
  26 #include "xfs_error.h"
  27 #include "xfs_quota.h"
  28 #include "xfs_trans_space.h"
  29 #include "xfs_buf_item.h"
  30 #include "xfs_trace.h"
  31 #include "xfs_attr_leaf.h"
  32 #include "xfs_filestream.h"
  33 #include "xfs_rmap.h"
  34 #include "xfs_ag.h"
  35 #include "xfs_ag_resv.h"
  36 #include "xfs_refcount.h"
  37 #include "xfs_icache.h"
  38 #include "xfs_iomap.h"
  39
  40 struct kmem_cache               *xfs_bmap_intent_cache;
  41
  42 /*
  43  * Miscellaneous helper functions
  44  */
  45
  46 /*
  47  * Compute and fill in the value of the maximum depth of a bmap btree
  48  * in this filesystem.  Done once, during mount.
  49  */
  50 void
  51 xfs_bmap_compute_maxlevels(
  52         xfs_mount_t     *mp,            /* file system mount structure */
  53         int             whichfork)      /* data or attr fork */
  54 {
  55         int             level;          /* btree level */
  56         uint            maxblocks;      /* max blocks at this level */
  57         uint            maxleafents;    /* max leaf entries possible */
  58         int             maxrootrecs;    /* max records in root block */
  59         int             minleafrecs;    /* min records in leaf block */
  60         int             minnoderecs;    /* min records in node block */
  61         int             sz;             /* root block size */
  62
  63         /*
  64          * The maximum number of extents in a file, hence the maximum number of
  65          * leaf entries, is controlled by the size of the on-disk extent count,
  66          * either a signed 32-bit number for the data fork, or a signed 16-bit
  67          * number for the attr fork.
  68          *
  69          * Note that we can no longer assume that if we are in ATTR1 that the
  70          * fork offset of all the inodes will be
  71          * (xfs_default_attroffset(ip) >> 3) because we could have mounted with
  72          * ATTR2 and then mounted back with ATTR1, keeping the i_forkoff's fixed
  73          * but probably at various positions. Therefore, for both ATTR1 and
  74          * ATTR2 we have to assume the worst case scenario of a minimum size
  75          * available.
  76          */
  77         if (whichfork == XFS_DATA_FORK) {
  78                 maxleafents = MAXEXTNUM;
  79                 sz = XFS_BMDR_SPACE_CALC(MINDBTPTRS);
  80         } else {
  81                 maxleafents = MAXAEXTNUM;
  82                 sz = XFS_BMDR_SPACE_CALC(MINABTPTRS);
  83         }
  84         maxrootrecs = xfs_bmdr_maxrecs(sz, 0);
  85         minleafrecs = mp->m_bmap_dmnr[0];
  86         minnoderecs = mp->m_bmap_dmnr[1];
  87         maxblocks = (maxleafents + minleafrecs - 1) / minleafrecs;
  88         for (level = 1; maxblocks > 1; level++) {
  89                 if (maxblocks <= maxrootrecs)
  90                         maxblocks = 1;
  91                 else
  92                         maxblocks = (maxblocks + minnoderecs - 1) / minnoderecs;
  93         }
  94         mp->m_bm_maxlevels[whichfork] = level;
  95         ASSERT(mp->m_bm_maxlevels[whichfork] <= xfs_bmbt_maxlevels_ondisk());
  96 }
  97
  98 unsigned int
  99 xfs_bmap_compute_attr_offset(
 100         struct xfs_mount        *mp)
 101 {
 102         if (mp->m_sb.sb_inodesize == 256)
 103                 return XFS_LITINO(mp) - XFS_BMDR_SPACE_CALC(MINABTPTRS);
 104         return XFS_BMDR_SPACE_CALC(6 * MINABTPTRS);
 105 }
 106
 107 STATIC int                              /* error */
 108 xfs_bmbt_lookup_eq(
 109         struct xfs_btree_cur    *cur,
 110         struct xfs_bmbt_irec    *irec,
 111         int                     *stat)  /* success/failure */
 112 {
 113         cur->bc_rec.b = *irec;
 114         return xfs_btree_lookup(cur, XFS_LOOKUP_EQ, stat);
 115 }
 116
 117 STATIC int                              /* error */
 118 xfs_bmbt_lookup_first(
 119         struct xfs_btree_cur    *cur,
 120         int                     *stat)  /* success/failure */
 121 {
 122         cur->bc_rec.b.br_startoff = 0;
 123         cur->bc_rec.b.br_startblock = 0;
 124         cur->bc_rec.b.br_blockcount = 0;
 125         return xfs_btree_lookup(cur, XFS_LOOKUP_GE, stat);
 126 }
 127
 128 /*
 129  * Check if the inode needs to be converted to btree format.
 130  */
 131 static inline bool xfs_bmap_needs_btree(struct xfs_inode *ip, int whichfork)
 132 {
 133         struct xfs_ifork *ifp = XFS_IFORK_PTR(ip, whichfork);
 134
 135         return whichfork != XFS_COW_FORK &&
 136                 ifp->if_format == XFS_DINODE_FMT_EXTENTS &&
 137                 ifp->if_nextents > XFS_IFORK_MAXEXT(ip, whichfork);
 138 }
 139
 140 /*
 141  * Check if the inode should be converted to extent format.
 142  */
 143 static inline bool xfs_bmap_wants_extents(struct xfs_inode *ip, int whichfork)
 144 {
 145         struct xfs_ifork *ifp = XFS_IFORK_PTR(ip, whichfork);
 146
 147         return whichfork != XFS_COW_FORK &&
 148                 ifp->if_format == XFS_DINODE_FMT_BTREE &&
 149                 ifp->if_nextents <= XFS_IFORK_MAXEXT(ip, whichfork);
 150 }
 151
 152 /*
 153  * Update the record referred to by cur to the value given by irec
 154  * This either works (return 0) or gets an EFSCORRUPTED error.
 155  */
 156 STATIC int
 157 xfs_bmbt_update(
 158         struct xfs_btree_cur    *cur,
 159         struct xfs_bmbt_irec    *irec)
 160 {
 161         union xfs_btree_rec     rec;
 162
 163         xfs_bmbt_disk_set_all(&rec.bmbt, irec);
 164         return xfs_btree_update(cur, &rec);
 165 }
 166
 167 /*
 168  * Compute the worst-case number of indirect blocks that will be used
 169  * for ip's delayed extent of length "len".
 170  */
 171 STATIC xfs_filblks_t
 172 xfs_bmap_worst_indlen(
 173         xfs_inode_t     *ip,            /* incore inode pointer */
 174         xfs_filblks_t   len)            /* delayed extent length */
 175 {
 176         int             level;          /* btree level number */
 177         int             maxrecs;        /* maximum record count at this level */
 178         xfs_mount_t     *mp;            /* mount structure */
 179         xfs_filblks_t   rval;           /* return value */
 180
 181         mp = ip->i_mount;
 182         maxrecs = mp->m_bmap_dmxr[0];
 183         for (level = 0, rval = 0;
 184              level < XFS_BM_MAXLEVELS(mp, XFS_DATA_FORK);
 185              level++) {
 186                 len += maxrecs - 1;
 187                 do_div(len, maxrecs);
 188                 rval += len;
 189                 if (len == 1)
 190                         return rval + XFS_BM_MAXLEVELS(mp, XFS_DATA_FORK) -
 191                                 level - 1;
 192                 if (level == 0)
 193                         maxrecs = mp->m_bmap_dmxr[1];
 194         }
 195         return rval;
 196 }
 197
 198 /*
 199  * Calculate the default attribute fork offset for newly created inodes.
 200  */
 201 uint
 202 xfs_default_attroffset(
 203         struct xfs_inode        *ip)
 204 {
 205         if (ip->i_df.if_format == XFS_DINODE_FMT_DEV)
 206                 return roundup(sizeof(xfs_dev_t), 8);
 207         return M_IGEO(ip->i_mount)->attr_fork_offset;
 208 }
 209
 210 /*
 211  * Helper routine to reset inode i_forkoff field when switching attribute fork
 212  * from local to extent format - we reset it where possible to make space
 213  * available for inline data fork extents.
 214  */
 215 STATIC void
 216 xfs_bmap_forkoff_reset(
 217         xfs_inode_t     *ip,
 218         int             whichfork)
 219 {
 220         if (whichfork == XFS_ATTR_FORK &&
 221             ip->i_df.if_format != XFS_DINODE_FMT_DEV &&
 222             ip->i_df.if_format != XFS_DINODE_FMT_BTREE) {
 223                 uint    dfl_forkoff = xfs_default_attroffset(ip) >> 3;
 224
 225                 if (dfl_forkoff > ip->i_forkoff)
 226                         ip->i_forkoff = dfl_forkoff;
 227         }
 228 }
 229
 230 #ifdef DEBUG
 231 STATIC struct xfs_buf *
 232 xfs_bmap_get_bp(
 233         struct xfs_btree_cur    *cur,
 234         xfs_fsblock_t           bno)
 235 {
 236         struct xfs_log_item     *lip;
 237         int                     i;
 238
 239         if (!cur)
 240                 return NULL;
 241
 242         for (i = 0; i < cur->bc_maxlevels; i++) {
 243                 if (!cur->bc_levels[i].bp)
 244                         break;
 245                 if (xfs_buf_daddr(cur->bc_levels[i].bp) == bno)
 246                         return cur->bc_levels[i].bp;
 247         }
 248
 249         /* Chase down all the log items to see if the bp is there */
 250         list_for_each_entry(lip, &cur->bc_tp->t_items, li_trans) {
 251                 struct xfs_buf_log_item *bip = (struct xfs_buf_log_item *)lip;
 252
 253                 if (bip->bli_item.li_type == XFS_LI_BUF &&
 254                     xfs_buf_daddr(bip->bli_buf) == bno)
 255                         return bip->bli_buf;
 256         }
 257
 258         return NULL;
 259 }
 260
 261 STATIC void
 262 xfs_check_block(
 263         struct xfs_btree_block  *block,
 264         xfs_mount_t             *mp,
 265         int                     root,
 266         short                   sz)
 267 {
 268         int                     i, j, dmxr;
 269         __be64                  *pp, *thispa;   /* pointer to block address */
 270         xfs_bmbt_key_t          *prevp, *keyp;
 271
 272         ASSERT(be16_to_cpu(block->bb_level) > 0);
 273
 274         prevp = NULL;
 275         for( i = 1; i <= xfs_btree_get_numrecs(block); i++) {
 276                 dmxr = mp->m_bmap_dmxr[0];
 277                 keyp = XFS_BMBT_KEY_ADDR(mp, block, i);
 278
 279                 if (prevp) {
 280                         ASSERT(be64_to_cpu(prevp->br_startoff) <
 281                                be64_to_cpu(keyp->br_startoff));
 282                 }
 283                 prevp = keyp;
 284
 285                 /*
 286                  * Compare the block numbers to see if there are dups.
 287                  */
 288                 if (root)
 289                         pp = XFS_BMAP_BROOT_PTR_ADDR(mp, block, i, sz);
 290                 else
 291                         pp = XFS_BMBT_PTR_ADDR(mp, block, i, dmxr);
 292
 293                 for (j = i+1; j <= be16_to_cpu(block->bb_numrecs); j++) {
 294                         if (root)
 295                                 thispa = XFS_BMAP_BROOT_PTR_ADDR(mp, block, j, sz);
 296                         else
 297                                 thispa = XFS_BMBT_PTR_ADDR(mp, block, j, dmxr);
 298                         if (*thispa == *pp) {
 299                                 xfs_warn(mp, "%s: thispa(%d) == pp(%d) %Ld",
 300                                         __func__, j, i,
 301                                         (unsigned long long)be64_to_cpu(*thispa));
 302                                 xfs_err(mp, "%s: ptrs are equal in node\n",
 303                                         __func__);
 304                                 xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
 305                         }
 306                 }
 307         }
 308 }
 309
 310 /*
 311  * Check that the extents for the inode ip are in the right order in all
 312  * btree leaves. THis becomes prohibitively expensive for large extent count
 313  * files, so don't bother with inodes that have more than 10,000 extents in
 314  * them. The btree record ordering checks will still be done, so for such large
 315  * bmapbt constructs that is going to catch most corruptions.
 316  */
 317 STATIC void
 318 xfs_bmap_check_leaf_extents(
 319         struct xfs_btree_cur    *cur,   /* btree cursor or null */
 320         xfs_inode_t             *ip,            /* incore inode pointer */
 321         int                     whichfork)      /* data or attr fork */
 322 {
 323         struct xfs_mount        *mp = ip->i_mount;
 324         struct xfs_ifork        *ifp = XFS_IFORK_PTR(ip, whichfork);
 325         struct xfs_btree_block  *block; /* current btree block */
 326         xfs_fsblock_t           bno;    /* block # of "block" */
 327         struct xfs_buf          *bp;    /* buffer for "block" */
 328         int                     error;  /* error return value */
 329         xfs_extnum_t            i=0, j; /* index into the extents list */
 330         int                     level;  /* btree level, for checking */
 331         __be64                  *pp;    /* pointer to block address */
 332         xfs_bmbt_rec_t          *ep;    /* pointer to current extent */
 333         xfs_bmbt_rec_t          last = {0, 0}; /* last extent in prev block */
 334         xfs_bmbt_rec_t          *nextp; /* pointer to next extent */
 335         int                     bp_release = 0;
 336
 337         if (ifp->if_format != XFS_DINODE_FMT_BTREE)
 338                 return;
 339
 340         /* skip large extent count inodes */
 341         if (ip->i_df.if_nextents > 10000)
 342                 return;
 343
 344         bno = NULLFSBLOCK;
 345         block = ifp->if_broot;
 346         /*
 347          * Root level must use BMAP_BROOT_PTR_ADDR macro to get ptr out.
 348          */
 349         level = be16_to_cpu(block->bb_level);
 350         ASSERT(level > 0);
 351         xfs_check_block(block, mp, 1, ifp->if_broot_bytes);
 352         pp = XFS_BMAP_BROOT_PTR_ADDR(mp, block, 1, ifp->if_broot_bytes);
 353         bno = be64_to_cpu(*pp);
 354
 355         ASSERT(bno != NULLFSBLOCK);
 356         ASSERT(XFS_FSB_TO_AGNO(mp, bno) < mp->m_sb.sb_agcount);
 357         ASSERT(XFS_FSB_TO_AGBNO(mp, bno) < mp->m_sb.sb_agblocks);
 358
 359         /*
 360          * Go down the tree until leaf level is reached, following the first
 361          * pointer (leftmost) at each level.
 362          */
 363         while (level-- > 0) {
 364                 /* See if buf is in cur first */
 365                 bp_release = 0;
 366                 bp = xfs_bmap_get_bp(cur, XFS_FSB_TO_DADDR(mp, bno));
 367                 if (!bp) {
 368                         bp_release = 1;
 369                         error = xfs_btree_read_bufl(mp, NULL, bno, &bp,
 370                                                 XFS_BMAP_BTREE_REF,
 371                                                 &xfs_bmbt_buf_ops);
 372                         if (error)
 373                                 goto error_norelse;
 374                 }
 375                 block = XFS_BUF_TO_BLOCK(bp);
 376                 if (level == 0)
 377                         break;
 378
 379                 /*
 380                  * Check this block for basic sanity (increasing keys and
 381                  * no duplicate blocks).
 382                  */
 383
 384                 xfs_check_block(block, mp, 0, 0);
 385                 pp = XFS_BMBT_PTR_ADDR(mp, block, 1, mp->m_bmap_dmxr[1]);
 386                 bno = be64_to_cpu(*pp);
 387                 if (XFS_IS_CORRUPT(mp, !xfs_verify_fsbno(mp, bno))) {
 388                         error = -EFSCORRUPTED;
 389                         goto error0;
 390                 }
 391                 if (bp_release) {
 392                         bp_release = 0;
 393                         xfs_trans_brelse(NULL, bp);
 394                 }
 395         }
 396
 397         /*
 398          * Here with bp and block set to the leftmost leaf node in the tree.
 399          */
 400         i = 0;
 401
 402         /*
 403          * Loop over all leaf nodes checking that all extents are in the right order.
 404          */
 405         for (;;) {
 406                 xfs_fsblock_t   nextbno;
 407                 xfs_extnum_t    num_recs;
 408
 409
 410                 num_recs = xfs_btree_get_numrecs(block);
 411
 412                 /*
 413                  * Read-ahead the next leaf block, if any.
 414                  */
 415
 416                 nextbno = be64_to_cpu(block->bb_u.l.bb_rightsib);
 417
 418                 /*
 419                  * Check all the extents to make sure they are OK.
 420                  * If we had a previous block, the last entry should
 421                  * conform with the first entry in this one.
 422                  */
 423
 424                 ep = XFS_BMBT_REC_ADDR(mp, block, 1);
 425                 if (i) {
 426                         ASSERT(xfs_bmbt_disk_get_startoff(&last) +
 427                                xfs_bmbt_disk_get_blockcount(&last) <=
 428                                xfs_bmbt_disk_get_startoff(ep));
 429                 }
 430                 for (j = 1; j < num_recs; j++) {
 431                         nextp = XFS_BMBT_REC_ADDR(mp, block, j + 1);
 432                         ASSERT(xfs_bmbt_disk_get_startoff(ep) +
 433                                xfs_bmbt_disk_get_blockcount(ep) <=
 434                                xfs_bmbt_disk_get_startoff(nextp));
 435                         ep = nextp;
 436                 }
 437
 438                 last = *ep;
 439                 i += num_recs;
 440                 if (bp_release) {
 441                         bp_release = 0;
 442                         xfs_trans_brelse(NULL, bp);
 443                 }
 444                 bno = nextbno;
 445                 /*
 446                  * If we've reached the end, stop.
 447                  */
 448                 if (bno == NULLFSBLOCK)
 449                         break;
 450
 451                 bp_release = 0;
 452                 bp = xfs_bmap_get_bp(cur, XFS_FSB_TO_DADDR(mp, bno));
 453                 if (!bp) {
 454                         bp_release = 1;
 455                         error = xfs_btree_read_bufl(mp, NULL, bno, &bp,
 456                                                 XFS_BMAP_BTREE_REF,
 457                                                 &xfs_bmbt_buf_ops);
 458                         if (error)
 459                                 goto error_norelse;
 460                 }
 461                 block = XFS_BUF_TO_BLOCK(bp);
 462         }
 463
 464         return;
 465
 466 error0:
 467         xfs_warn(mp, "%s: at error0", __func__);
 468         if (bp_release)
 469                 xfs_trans_brelse(NULL, bp);
 470 error_norelse:
 471         xfs_warn(mp, "%s: BAD after btree leaves for %d extents",
 472                 __func__, i);
 473         xfs_err(mp, "%s: CORRUPTED BTREE OR SOMETHING", __func__);
 474         xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
 475         return;
 476 }
 477
 478 /*
 479  * Validate that the bmbt_irecs being returned from bmapi are valid
 480  * given the caller's original parameters.  Specifically check the
 481  * ranges of the returned irecs to ensure that they only extend beyond
 482  * the given parameters if the XFS_BMAPI_ENTIRE flag was set.
 483  */
 484 STATIC void
 485 xfs_bmap_validate_ret(
 486         xfs_fileoff_t           bno,
 487         xfs_filblks_t           len,
 488         int                     flags,
 489         xfs_bmbt_irec_t         *mval,
 490         int                     nmap,
 491         int                     ret_nmap)
 492 {
 493         int                     i;              /* index to map values */
 494
 495         ASSERT(ret_nmap <= nmap);
 496
 497         for (i = 0; i < ret_nmap; i++) {
 498                 ASSERT(mval[i].br_blockcount > 0);
 499                 if (!(flags & XFS_BMAPI_ENTIRE)) {
 500                         ASSERT(mval[i].br_startoff >= bno);
 501                         ASSERT(mval[i].br_blockcount <= len);
 502                         ASSERT(mval[i].br_startoff + mval[i].br_blockcount <=
 503                                bno + len);
 504                 } else {
 505                         ASSERT(mval[i].br_startoff < bno + len);
 506                         ASSERT(mval[i].br_startoff + mval[i].br_blockcount >
 507                                bno);
 508                 }
 509                 ASSERT(i == 0 ||
 510                        mval[i - 1].br_startoff + mval[i - 1].br_blockcount ==
 511                        mval[i].br_startoff);
 512                 ASSERT(mval[i].br_startblock != DELAYSTARTBLOCK &&
 513                        mval[i].br_startblock != HOLESTARTBLOCK);
 514                 ASSERT(mval[i].br_state == XFS_EXT_NORM ||
 515                        mval[i].br_state == XFS_EXT_UNWRITTEN);
 516         }
 517 }
 518
 519 #else
 520 #define xfs_bmap_check_leaf_extents(cur, ip, whichfork)         do { } while (0)
 521 #define xfs_bmap_validate_ret(bno,len,flags,mval,onmap,nmap)    do { } while (0)
 522 #endif /* DEBUG */
 523
 524 /*
 525  * Inode fork format manipulation functions
 526  */
 527
 528 /*
 529  * Convert the inode format to extent format if it currently is in btree format,
 530  * but the extent list is small enough that it fits into the extent format.
 531  *
 532  * Since the extents are already in-core, all we have to do is give up the space
 533  * for the btree root and pitch the leaf block.
 534  */
 535 STATIC int                              /* error */
 536 xfs_bmap_btree_to_extents(
 537         struct xfs_trans        *tp,    /* transaction pointer */
 538         struct xfs_inode        *ip,    /* incore inode pointer */
 539         struct xfs_btree_cur    *cur,   /* btree cursor */
 540         int                     *logflagsp, /* inode logging flags */
 541         int                     whichfork)  /* data or attr fork */
 542 {
 543         struct xfs_ifork        *ifp = XFS_IFORK_PTR(ip, whichfork);
 544         struct xfs_mount        *mp = ip->i_mount;
 545         struct xfs_btree_block  *rblock = ifp->if_broot;
 546         struct xfs_btree_block  *cblock;/* child btree block */
 547         xfs_fsblock_t           cbno;   /* child block number */
 548         struct xfs_buf          *cbp;   /* child block's buffer */
 549         int                     error;  /* error return value */
 550         __be64                  *pp;    /* ptr to block address */
 551         struct xfs_owner_info   oinfo;
 552
 553         /* check if we actually need the extent format first: */
 554         if (!xfs_bmap_wants_extents(ip, whichfork))
 555                 return 0;
 556
 557         ASSERT(cur);
 558         ASSERT(whichfork != XFS_COW_FORK);
 559         ASSERT(ifp->if_format == XFS_DINODE_FMT_BTREE);
 560         ASSERT(be16_to_cpu(rblock->bb_level) == 1);
 561         ASSERT(be16_to_cpu(rblock->bb_numrecs) == 1);
 562         ASSERT(xfs_bmbt_maxrecs(mp, ifp->if_broot_bytes, 0) == 1);
 563
 564         pp = XFS_BMAP_BROOT_PTR_ADDR(mp, rblock, 1, ifp->if_broot_bytes);
 565         cbno = be64_to_cpu(*pp);
 566 #ifdef DEBUG
 567         if (XFS_IS_CORRUPT(cur->bc_mp, !xfs_btree_check_lptr(cur, cbno, 1)))
 568                 return -EFSCORRUPTED;
 569 #endif
 570         error = xfs_btree_read_bufl(mp, tp, cbno, &cbp, XFS_BMAP_BTREE_REF,
 571                                 &xfs_bmbt_buf_ops);
 572         if (error)
 573                 return error;
 574         cblock = XFS_BUF_TO_BLOCK(cbp);
 575         if ((error = xfs_btree_check_block(cur, cblock, 0, cbp)))
 576                 return error;
 577         xfs_rmap_ino_bmbt_owner(&oinfo, ip->i_ino, whichfork);
 578         xfs_free_extent_later(cur->bc_tp, cbno, 1, &oinfo);
 579         ip->i_nblocks--;
 580         xfs_trans_mod_dquot_byino(tp, ip, XFS_TRANS_DQ_BCOUNT, -1L);
 581         xfs_trans_binval(tp, cbp);
 582         if (cur->bc_levels[0].bp == cbp)
 583                 cur->bc_levels[0].bp = NULL;
 584         xfs_iroot_realloc(ip, -1, whichfork);
 585         ASSERT(ifp->if_broot == NULL);
 586         ifp->if_format = XFS_DINODE_FMT_EXTENTS;
 587         *logflagsp |= XFS_ILOG_CORE | xfs_ilog_fext(whichfork);
 588         return 0;
 589 }
 590
 591 /*
 592  * Convert an extents-format file into a btree-format file.
 593  * The new file will have a root block (in the inode) and a single child block.
 594  */
 595 STATIC int                                      /* error */
 596 xfs_bmap_extents_to_btree(
 597         struct xfs_trans        *tp,            /* transaction pointer */
 598         struct xfs_inode        *ip,            /* incore inode pointer */
 599         struct xfs_btree_cur    **curp,         /* cursor returned to caller */
 600         int                     wasdel,         /* converting a delayed alloc */
 601         int                     *logflagsp,     /* inode logging flags */
 602         int                     whichfork)      /* data or attr fork */
 603 {
 604         struct xfs_btree_block  *ablock;        /* allocated (child) bt block */
 605         struct xfs_buf          *abp;           /* buffer for ablock */
 606         struct xfs_alloc_arg    args;           /* allocation arguments */
 607         struct xfs_bmbt_rec     *arp;           /* child record pointer */
 608         struct xfs_btree_block  *block;         /* btree root block */
 609         struct xfs_btree_cur    *cur;           /* bmap btree cursor */
 610         int                     error;          /* error return value */
 611         struct xfs_ifork        *ifp;           /* inode fork pointer */
 612         struct xfs_bmbt_key     *kp;            /* root block key pointer */
 613         struct xfs_mount        *mp;            /* mount structure */
 614         xfs_bmbt_ptr_t          *pp;            /* root block address pointer */
 615         struct xfs_iext_cursor  icur;
 616         struct xfs_bmbt_irec    rec;
 617         xfs_extnum_t            cnt = 0;
 618
 619         mp = ip->i_mount;
 620         ASSERT(whichfork != XFS_COW_FORK);
 621         ifp = XFS_IFORK_PTR(ip, whichfork);
 622         ASSERT(ifp->if_format == XFS_DINODE_FMT_EXTENTS);
 623
 624         /*
 625          * Make space in the inode incore. This needs to be undone if we fail
 626          * to expand the root.
 627          */
 628         xfs_iroot_realloc(ip, 1, whichfork);
 629
 630         /*
 631          * Fill in the root.
 632          */
 633         block = ifp->if_broot;
 634         xfs_btree_init_block_int(mp, block, XFS_BUF_DADDR_NULL,
 635                                  XFS_BTNUM_BMAP, 1, 1, ip->i_ino,
 636                                  XFS_BTREE_LONG_PTRS);
 637         /*
 638          * Need a cursor.  Can't allocate until bb_level is filled in.
 639          */
 640         cur = xfs_bmbt_init_cursor(mp, tp, ip, whichfork);
 641         cur->bc_ino.flags = wasdel ? XFS_BTCUR_BMBT_WASDEL : 0;
 642         /*
 643          * Convert to a btree with two levels, one record in root.
 644          */
 645         ifp->if_format = XFS_DINODE_FMT_BTREE;
 646         memset(&args, 0, sizeof(args));
 647         args.tp = tp;
 648         args.mp = mp;
 649         xfs_rmap_ino_bmbt_owner(&args.oinfo, ip->i_ino, whichfork);
 650         if (tp->t_firstblock == NULLFSBLOCK) {
 651                 args.type = XFS_ALLOCTYPE_START_BNO;
 652                 args.fsbno = XFS_INO_TO_FSB(mp, ip->i_ino);
 653         } else if (tp->t_flags & XFS_TRANS_LOWMODE) {
 654                 args.type = XFS_ALLOCTYPE_START_BNO;
 655                 args.fsbno = tp->t_firstblock;
 656         } else {
 657                 args.type = XFS_ALLOCTYPE_NEAR_BNO;
 658                 args.fsbno = tp->t_firstblock;
 659         }
 660         args.minlen = args.maxlen = args.prod = 1;
 661         args.wasdel = wasdel;
 662         *logflagsp = 0;
 663         error = xfs_alloc_vextent(&args);
 664         if (error)
 665                 goto out_root_realloc;
 666
 667         if (WARN_ON_ONCE(args.fsbno == NULLFSBLOCK)) {
 668                 error = -ENOSPC;
 669                 goto out_root_realloc;
 670         }
 671
 672         /*
 673          * Allocation can't fail, the space was reserved.
 674          */
 675         ASSERT(tp->t_firstblock == NULLFSBLOCK ||
 676                args.agno >= XFS_FSB_TO_AGNO(mp, tp->t_firstblock));
 677         tp->t_firstblock = args.fsbno;
 678         cur->bc_ino.allocated++;
 679         ip->i_nblocks++;
 680         xfs_trans_mod_dquot_byino(tp, ip, XFS_TRANS_DQ_BCOUNT, 1L);
 681         error = xfs_trans_get_buf(tp, mp->m_ddev_targp,
 682                         XFS_FSB_TO_DADDR(mp, args.fsbno),
 683                         mp->m_bsize, 0, &abp);
 684         if (error)
 685                 goto out_unreserve_dquot;
 686
 687         /*
 688          * Fill in the child block.
 689          */
 690         abp->b_ops = &xfs_bmbt_buf_ops;
 691         ablock = XFS_BUF_TO_BLOCK(abp);
 692         xfs_btree_init_block_int(mp, ablock, xfs_buf_daddr(abp),
 693                                 XFS_BTNUM_BMAP, 0, 0, ip->i_ino,
 694                                 XFS_BTREE_LONG_PTRS);
 695
 696         for_each_xfs_iext(ifp, &icur, &rec) {
 697                 if (isnullstartblock(rec.br_startblock))
 698                         continue;
 699                 arp = XFS_BMBT_REC_ADDR(mp, ablock, 1 + cnt);
 700                 xfs_bmbt_disk_set_all(arp, &rec);
 701                 cnt++;
 702         }
 703         ASSERT(cnt == ifp->if_nextents);
 704         xfs_btree_set_numrecs(ablock, cnt);
 705
 706         /*
 707          * Fill in the root key and pointer.
 708          */
 709         kp = XFS_BMBT_KEY_ADDR(mp, block, 1);
 710         arp = XFS_BMBT_REC_ADDR(mp, ablock, 1);
 711         kp->br_startoff = cpu_to_be64(xfs_bmbt_disk_get_startoff(arp));
 712         pp = XFS_BMBT_PTR_ADDR(mp, block, 1, xfs_bmbt_get_maxrecs(cur,
 713                                                 be16_to_cpu(block->bb_level)));
 714         *pp = cpu_to_be64(args.fsbno);
 715
 716         /*
 717          * Do all this logging at the end so that
 718          * the root is at the right level.
 719          */
 720         xfs_btree_log_block(cur, abp, XFS_BB_ALL_BITS);
 721         xfs_btree_log_recs(cur, abp, 1, be16_to_cpu(ablock->bb_numrecs));
 722         ASSERT(*curp == NULL);
 723         *curp = cur;
 724         *logflagsp = XFS_ILOG_CORE | xfs_ilog_fbroot(whichfork);
 725         return 0;
 726
 727 out_unreserve_dquot:
 728         xfs_trans_mod_dquot_byino(tp, ip, XFS_TRANS_DQ_BCOUNT, -1L);
 729 out_root_realloc:
 730         xfs_iroot_realloc(ip, -1, whichfork);
 731         ifp->if_format = XFS_DINODE_FMT_EXTENTS;
 732         ASSERT(ifp->if_broot == NULL);
 733         xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
 734
 735         return error;
 736 }
 737
 738 /*
 739  * Convert a local file to an extents file.
 740  * This code is out of bounds for data forks of regular files,
 741  * since the file data needs to get logged so things will stay consistent.
 742  * (The bmap-level manipulations are ok, though).
 743  */
 744 void
 745 xfs_bmap_local_to_extents_empty(
 746         struct xfs_trans        *tp,
 747         struct xfs_inode        *ip,
 748         int                     whichfork)
 749 {
 750         struct xfs_ifork        *ifp = XFS_IFORK_PTR(ip, whichfork);
 751
 752         ASSERT(whichfork != XFS_COW_FORK);
 753         ASSERT(ifp->if_format == XFS_DINODE_FMT_LOCAL);
 754         ASSERT(ifp->if_bytes == 0);
 755         ASSERT(ifp->if_nextents == 0);
 756
 757         xfs_bmap_forkoff_reset(ip, whichfork);
 758         ifp->if_u1.if_root = NULL;
 759         ifp->if_height = 0;
 760         ifp->if_format = XFS_DINODE_FMT_EXTENTS;
 761         xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
 762 }
 763
 764
 765 STATIC int                              /* error */
 766 xfs_bmap_local_to_extents(
 767         xfs_trans_t     *tp,            /* transaction pointer */
 768         xfs_inode_t     *ip,            /* incore inode pointer */
 769         xfs_extlen_t    total,          /* total blocks needed by transaction */
 770         int             *logflagsp,     /* inode logging flags */
 771         int             whichfork,
 772         void            (*init_fn)(struct xfs_trans *tp,
 773                                    struct xfs_buf *bp,
 774                                    struct xfs_inode *ip,
 775                                    struct xfs_ifork *ifp))
 776 {
 777         int             error = 0;
 778         int             flags;          /* logging flags returned */
 779         struct xfs_ifork *ifp;          /* inode fork pointer */
 780         xfs_alloc_arg_t args;           /* allocation arguments */
 781         struct xfs_buf  *bp;            /* buffer for extent block */
 782         struct xfs_bmbt_irec rec;
 783         struct xfs_iext_cursor icur;
 784
 785         /*
 786          * We don't want to deal with the case of keeping inode data inline yet.
 787          * So sending the data fork of a regular inode is invalid.
 788          */
 789         ASSERT(!(S_ISREG(VFS_I(ip)->i_mode) && whichfork == XFS_DATA_FORK));
 790         ifp = XFS_IFORK_PTR(ip, whichfork);
 791         ASSERT(ifp->if_format == XFS_DINODE_FMT_LOCAL);
 792
 793         if (!ifp->if_bytes) {
 794                 xfs_bmap_local_to_extents_empty(tp, ip, whichfork);
 795                 flags = XFS_ILOG_CORE;
 796                 goto done;
 797         }
 798
 799         flags = 0;
 800         error = 0;
 801         memset(&args, 0, sizeof(args));
 802         args.tp = tp;
 803         args.mp = ip->i_mount;
 804         xfs_rmap_ino_owner(&args.oinfo, ip->i_ino, whichfork, 0);
 805         /*
 806          * Allocate a block.  We know we need only one, since the
 807          * file currently fits in an inode.
 808          */
 809         if (tp->t_firstblock == NULLFSBLOCK) {
 810                 args.fsbno = XFS_INO_TO_FSB(args.mp, ip->i_ino);
 811                 args.type = XFS_ALLOCTYPE_START_BNO;
 812         } else {
 813                 args.fsbno = tp->t_firstblock;
 814                 args.type = XFS_ALLOCTYPE_NEAR_BNO;
 815         }
 816         args.total = total;
 817         args.minlen = args.maxlen = args.prod = 1;
 818         error = xfs_alloc_vextent(&args);
 819         if (error)
 820                 goto done;
 821
 822         /* Can't fail, the space was reserved. */
 823         ASSERT(args.fsbno != NULLFSBLOCK);
 824         ASSERT(args.len == 1);
 825         tp->t_firstblock = args.fsbno;
 826         error = xfs_trans_get_buf(tp, args.mp->m_ddev_targp,
 827                         XFS_FSB_TO_DADDR(args.mp, args.fsbno),
 828                         args.mp->m_bsize, 0, &bp);
 829         if (error)
 830                 goto done;
 831
 832         /*
 833          * Initialize the block, copy the data and log the remote buffer.
 834          *
 835          * The callout is responsible for logging because the remote format
 836          * might differ from the local format and thus we don't know how much to
 837          * log here. Note that init_fn must also set the buffer log item type
 838          * correctly.
 839          */
 840         init_fn(tp, bp, ip, ifp);
 841
 842         /* account for the change in fork size */
 843         xfs_idata_realloc(ip, -ifp->if_bytes, whichfork);
 844         xfs_bmap_local_to_extents_empty(tp, ip, whichfork);
 845         flags |= XFS_ILOG_CORE;
 846
 847         ifp->if_u1.if_root = NULL;
 848         ifp->if_height = 0;
 849
 850         rec.br_startoff = 0;
 851         rec.br_startblock = args.fsbno;
 852         rec.br_blockcount = 1;
 853         rec.br_state = XFS_EXT_NORM;
 854         xfs_iext_first(ifp, &icur);
 855         xfs_iext_insert(ip, &icur, &rec, 0);
 856
 857         ifp->if_nextents = 1;
 858         ip->i_nblocks = 1;
 859         xfs_trans_mod_dquot_byino(tp, ip,
 860                 XFS_TRANS_DQ_BCOUNT, 1L);
 861         flags |= xfs_ilog_fext(whichfork);
 862
 863 done:
 864         *logflagsp = flags;
 865         return error;
 866 }
 867
 868 /*
 869  * Called from xfs_bmap_add_attrfork to handle btree format files.
 870  */
 871 STATIC int                                      /* error */
 872 xfs_bmap_add_attrfork_btree(
 873         xfs_trans_t             *tp,            /* transaction pointer */
 874         xfs_inode_t             *ip,            /* incore inode pointer */
 875         int                     *flags)         /* inode logging flags */
 876 {
 877         struct xfs_btree_block  *block = ip->i_df.if_broot;
 878         struct xfs_btree_cur    *cur;           /* btree cursor */
 879         int                     error;          /* error return value */
 880         xfs_mount_t             *mp;            /* file system mount struct */
 881         int                     stat;           /* newroot status */
 882
 883         mp = ip->i_mount;
 884
 885         if (XFS_BMAP_BMDR_SPACE(block) <= XFS_IFORK_DSIZE(ip))
 886                 *flags |= XFS_ILOG_DBROOT;
 887         else {
 888                 cur = xfs_bmbt_init_cursor(mp, tp, ip, XFS_DATA_FORK);
 889                 error = xfs_bmbt_lookup_first(cur, &stat);
 890                 if (error)
 891                         goto error0;
 892                 /* must be at least one entry */
 893                 if (XFS_IS_CORRUPT(mp, stat != 1)) {
 894                         error = -EFSCORRUPTED;
 895                         goto error0;
 896                 }
 897                 if ((error = xfs_btree_new_iroot(cur, flags, &stat)))
 898                         goto error0;
 899                 if (stat == 0) {
 900                         xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
 901                         return -ENOSPC;
 902                 }
 903                 cur->bc_ino.allocated = 0;
 904                 xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
 905         }
 906         return 0;
 907 error0:
 908         xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
 909         return error;
 910 }
 911
 912 /*
 913  * Called from xfs_bmap_add_attrfork to handle extents format files.
 914  */
 915 STATIC int                                      /* error */
 916 xfs_bmap_add_attrfork_extents(
 917         struct xfs_trans        *tp,            /* transaction pointer */
 918         struct xfs_inode        *ip,            /* incore inode pointer */
 919         int                     *flags)         /* inode logging flags */
 920 {
 921         struct xfs_btree_cur    *cur;           /* bmap btree cursor */
 922         int                     error;          /* error return value */
 923
 924         if (ip->i_df.if_nextents * sizeof(struct xfs_bmbt_rec) <=
 925             XFS_IFORK_DSIZE(ip))
 926                 return 0;
 927         cur = NULL;
 928         error = xfs_bmap_extents_to_btree(tp, ip, &cur, 0, flags,
 929                                           XFS_DATA_FORK);
 930         if (cur) {
 931                 cur->bc_ino.allocated = 0;
 932                 xfs_btree_del_cursor(cur, error);
 933         }
 934         return error;
 935 }
 936
 937 /*
 938  * Called from xfs_bmap_add_attrfork to handle local format files. Each
 939  * different data fork content type needs a different callout to do the
 940  * conversion. Some are basic and only require special block initialisation
 941  * callouts for the data formating, others (directories) are so specialised they
 942  * handle everything themselves.
 943  *
 944  * XXX (dgc): investigate whether directory conversion can use the generic
 945  * formatting callout. It should be possible - it's just a very complex
 946  * formatter.
 947  */
 948 STATIC int                                      /* error */
 949 xfs_bmap_add_attrfork_local(
 950         struct xfs_trans        *tp,            /* transaction pointer */
 951         struct xfs_inode        *ip,            /* incore inode pointer */
 952         int                     *flags)         /* inode logging flags */
 953 {
 954         struct xfs_da_args      dargs;          /* args for dir/attr code */
 955
 956         if (ip->i_df.if_bytes <= XFS_IFORK_DSIZE(ip))
 957                 return 0;
 958
 959         if (S_ISDIR(VFS_I(ip)->i_mode)) {
 960                 memset(&dargs, 0, sizeof(dargs));
 961                 dargs.geo = ip->i_mount->m_dir_geo;
 962                 dargs.dp = ip;
 963                 dargs.total = dargs.geo->fsbcount;
 964                 dargs.whichfork = XFS_DATA_FORK;
 965                 dargs.trans = tp;
 966                 return xfs_dir2_sf_to_block(&dargs);
 967         }
 968
 969         if (S_ISLNK(VFS_I(ip)->i_mode))
 970                 return xfs_bmap_local_to_extents(tp, ip, 1, flags,
 971                                                  XFS_DATA_FORK,
 972                                                  xfs_symlink_local_to_remote);
 973
 974         /* should only be called for types that support local format data */
 975         ASSERT(0);
 976         return -EFSCORRUPTED;
 977 }
 978
 979 /*
 980  * Set an inode attr fork offset based on the format of the data fork.
 981  */
 982 static int
 983 xfs_bmap_set_attrforkoff(
 984         struct xfs_inode        *ip,
 985         int                     size,
 986         int                     *version)
 987 {
 988         int                     default_size = xfs_default_attroffset(ip) >> 3;
 989
 990         switch (ip->i_df.if_format) {
 991         case XFS_DINODE_FMT_DEV:
 992                 ip->i_forkoff = default_size;
 993                 break;
 994         case XFS_DINODE_FMT_LOCAL:
 995         case XFS_DINODE_FMT_EXTENTS:
 996         case XFS_DINODE_FMT_BTREE:
 997                 ip->i_forkoff = xfs_attr_shortform_bytesfit(ip, size);
 998                 if (!ip->i_forkoff)
 999                         ip->i_forkoff = default_size;
1000                 else if (xfs_has_attr2(ip->i_mount) && version)
1001                         *version = 2;
1002                 break;
1003         default:
1004                 ASSERT(0);
1005                 return -EINVAL;
1006         }
1007
1008         return 0;
1009 }
1010
1011 /*
1012  * Convert inode from non-attributed to attributed.
1013  * Must not be in a transaction, ip must not be locked.
1014  */
1015 int                                             /* error code */
1016 xfs_bmap_add_attrfork(
1017         xfs_inode_t             *ip,            /* incore inode pointer */
1018         int                     size,           /* space new attribute needs */
1019         int                     rsvd)           /* xact may use reserved blks */
1020 {
1021         xfs_mount_t             *mp;            /* mount structure */
1022         xfs_trans_t             *tp;            /* transaction pointer */
1023         int                     blks;           /* space reservation */
1024         int                     version = 1;    /* superblock attr version */
1025         int                     logflags;       /* logging flags */
1026         int                     error;          /* error return value */
1027
1028         ASSERT(XFS_IFORK_Q(ip) == 0);
1029
1030         mp = ip->i_mount;
1031         ASSERT(!XFS_NOT_DQATTACHED(mp, ip));
1032
1033         blks = XFS_ADDAFORK_SPACE_RES(mp);
1034
1035         error = xfs_trans_alloc_inode(ip, &M_RES(mp)->tr_addafork, blks, 0,
1036                         rsvd, &tp);
1037         if (error)
1038                 return error;
1039         if (XFS_IFORK_Q(ip))
1040                 goto trans_cancel;
1041
1042         xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1043         error = xfs_bmap_set_attrforkoff(ip, size, &version);
1044         if (error)
1045                 goto trans_cancel;
1046         ASSERT(ip->i_afp == NULL);
1047
1048         ip->i_afp = xfs_ifork_alloc(XFS_DINODE_FMT_EXTENTS, 0);
1049         logflags = 0;
1050         switch (ip->i_df.if_format) {
1051         case XFS_DINODE_FMT_LOCAL:
1052                 error = xfs_bmap_add_attrfork_local(tp, ip, &logflags);
1053                 break;
1054         case XFS_DINODE_FMT_EXTENTS:
1055                 error = xfs_bmap_add_attrfork_extents(tp, ip, &logflags);
1056                 break;
1057         case XFS_DINODE_FMT_BTREE:
1058                 error = xfs_bmap_add_attrfork_btree(tp, ip, &logflags);
1059                 break;
1060         default:
1061                 error = 0;
1062                 break;
1063         }
1064         if (logflags)
1065                 xfs_trans_log_inode(tp, ip, logflags);
1066         if (error)
1067                 goto trans_cancel;
1068         if (!xfs_has_attr(mp) ||
1069            (!xfs_has_attr2(mp) && version == 2)) {
1070                 bool log_sb = false;
1071
1072                 spin_lock(&mp->m_sb_lock);
1073                 if (!xfs_has_attr(mp)) {
1074                         xfs_add_attr(mp);
1075                         log_sb = true;
1076                 }
1077                 if (!xfs_has_attr2(mp) && version == 2) {
1078                         xfs_add_attr2(mp);
1079                         log_sb = true;
1080                 }
1081                 spin_unlock(&mp->m_sb_lock);
1082                 if (log_sb)
1083                         xfs_log_sb(tp);
1084         }
1085
1086         error = xfs_trans_commit(tp);
1087         xfs_iunlock(ip, XFS_ILOCK_EXCL);
1088         return error;
1089
1090 trans_cancel:
1091         xfs_trans_cancel(tp);
1092         xfs_iunlock(ip, XFS_ILOCK_EXCL);
1093         return error;
1094 }
1095
1096 /*
1097  * Internal and external extent tree search functions.
1098  */
1099
1100 struct xfs_iread_state {
1101         struct xfs_iext_cursor  icur;
1102         xfs_extnum_t            loaded;
1103 };
1104
1105 /* Stuff every bmbt record from this block into the incore extent map. */
1106 static int
1107 xfs_iread_bmbt_block(
1108         struct xfs_btree_cur    *cur,
1109         int                     level,
1110         void                    *priv)
1111 {
1112         struct xfs_iread_state  *ir = priv;
1113         struct xfs_mount        *mp = cur->bc_mp;
1114         struct xfs_inode        *ip = cur->bc_ino.ip;
1115         struct xfs_btree_block  *block;
1116         struct xfs_buf          *bp;
1117         struct xfs_bmbt_rec     *frp;
1118         xfs_extnum_t            num_recs;
1119         xfs_extnum_t            j;
1120         int                     whichfork = cur->bc_ino.whichfork;
1121         struct xfs_ifork        *ifp = XFS_IFORK_PTR(ip, whichfork);
1122
1123         block = xfs_btree_get_block(cur, level, &bp);
1124
1125         /* Abort if we find more records than nextents. */
1126         num_recs = xfs_btree_get_numrecs(block);
1127         if (unlikely(ir->loaded + num_recs > ifp->if_nextents)) {
1128                 xfs_warn(ip->i_mount, "corrupt dinode %llu, (btree extents).",
1129                                 (unsigned long long)ip->i_ino);
1130                 xfs_inode_verifier_error(ip, -EFSCORRUPTED, __func__, block,
1131                                 sizeof(*block), __this_address);
1132                 return -EFSCORRUPTED;
1133         }
1134
1135         /* Copy records into the incore cache. */
1136         frp = XFS_BMBT_REC_ADDR(mp, block, 1);
1137         for (j = 0; j < num_recs; j++, frp++, ir->loaded++) {
1138                 struct xfs_bmbt_irec    new;
1139                 xfs_failaddr_t          fa;
1140
1141                 xfs_bmbt_disk_get_all(frp, &new);
1142                 fa = xfs_bmap_validate_extent(ip, whichfork, &new);
1143                 if (fa) {
1144                         xfs_inode_verifier_error(ip, -EFSCORRUPTED,
1145                                         "xfs_iread_extents(2)", frp,
1146                                         sizeof(*frp), fa);
1147                         return -EFSCORRUPTED;
1148                 }
1149                 xfs_iext_insert(ip, &ir->icur, &new,
1150                                 xfs_bmap_fork_to_state(whichfork));
1151                 trace_xfs_read_extent(ip, &ir->icur,
1152                                 xfs_bmap_fork_to_state(whichfork), _THIS_IP_);
1153                 xfs_iext_next(ifp, &ir->icur);
1154         }
1155
1156         return 0;
1157 }
1158
1159 /*
1160  * Read in extents from a btree-format inode.
1161  */
1162 int
1163 xfs_iread_extents(
1164         struct xfs_trans        *tp,
1165         struct xfs_inode        *ip,
1166         int                     whichfork)
1167 {
1168         struct xfs_iread_state  ir;
1169         struct xfs_ifork        *ifp = XFS_IFORK_PTR(ip, whichfork);
1170         struct xfs_mount        *mp = ip->i_mount;
1171         struct xfs_btree_cur    *cur;
1172         int                     error;
1173
1174         if (!xfs_need_iread_extents(ifp))
1175                 return 0;
1176
1177         ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
1178
1179         ir.loaded = 0;
1180         xfs_iext_first(ifp, &ir.icur);
1181         cur = xfs_bmbt_init_cursor(mp, tp, ip, whichfork);
1182         error = xfs_btree_visit_blocks(cur, xfs_iread_bmbt_block,
1183                         XFS_BTREE_VISIT_RECORDS, &ir);
1184         xfs_btree_del_cursor(cur, error);
1185         if (error)
1186                 goto out;
1187
1188         if (XFS_IS_CORRUPT(mp, ir.loaded != ifp->if_nextents)) {
1189                 error = -EFSCORRUPTED;
1190                 goto out;
1191         }
1192         ASSERT(ir.loaded == xfs_iext_count(ifp));
1193         return 0;
1194 out:
1195         xfs_iext_destroy(ifp);
1196         return error;
1197 }
1198
1199 /*
1200  * Returns the relative block number of the first unused block(s) in the given
1201  * fork with at least "len" logically contiguous blocks free.  This is the
1202  * lowest-address hole if the fork has holes, else the first block past the end
1203  * of fork.  Return 0 if the fork is currently local (in-inode).
1204  */
1205 int                                             /* error */
1206 xfs_bmap_first_unused(
1207         struct xfs_trans        *tp,            /* transaction pointer */
1208         struct xfs_inode        *ip,            /* incore inode */
1209         xfs_extlen_t            len,            /* size of hole to find */
1210         xfs_fileoff_t           *first_unused,  /* unused block */
1211         int                     whichfork)      /* data or attr fork */
1212 {
1213         struct xfs_ifork        *ifp = XFS_IFORK_PTR(ip, whichfork);
1214         struct xfs_bmbt_irec    got;
1215         struct xfs_iext_cursor  icur;
1216         xfs_fileoff_t           lastaddr = 0;
1217         xfs_fileoff_t           lowest, max;
1218         int                     error;
1219
1220         if (ifp->if_format == XFS_DINODE_FMT_LOCAL) {
1221                 *first_unused = 0;
1222                 return 0;
1223         }
1224
1225         ASSERT(xfs_ifork_has_extents(ifp));
1226
1227         error = xfs_iread_extents(tp, ip, whichfork);
1228         if (error)
1229                 return error;
1230
1231         lowest = max = *first_unused;
1232         for_each_xfs_iext(ifp, &icur, &got) {
1233                 /*
1234                  * See if the hole before this extent will work.
1235                  */
1236                 if (got.br_startoff >= lowest + len &&
1237                     got.br_startoff - max >= len)
1238                         break;
1239                 lastaddr = got.br_startoff + got.br_blockcount;
1240                 max = XFS_FILEOFF_MAX(lastaddr, lowest);
1241         }
1242
1243         *first_unused = max;
1244         return 0;
1245 }
1246
1247 /*
1248  * Returns the file-relative block number of the last block - 1 before
1249  * last_block (input value) in the file.
1250  * This is not based on i_size, it is based on the extent records.
1251  * Returns 0 for local files, as they do not have extent records.
1252  */
1253 int                                             /* error */
1254 xfs_bmap_last_before(
1255         struct xfs_trans        *tp,            /* transaction pointer */
1256         struct xfs_inode        *ip,            /* incore inode */
1257         xfs_fileoff_t           *last_block,    /* last block */
1258         int                     whichfork)      /* data or attr fork */
1259 {
1260         struct xfs_ifork        *ifp = XFS_IFORK_PTR(ip, whichfork);
1261         struct xfs_bmbt_irec    got;
1262         struct xfs_iext_cursor  icur;
1263         int                     error;
1264
1265         switch (ifp->if_format) {
1266         case XFS_DINODE_FMT_LOCAL:
1267                 *last_block = 0;
1268                 return 0;
1269         case XFS_DINODE_FMT_BTREE:
1270         case XFS_DINODE_FMT_EXTENTS:
1271                 break;
1272         default:
1273                 ASSERT(0);
1274                 return -EFSCORRUPTED;
1275         }
1276
1277         error = xfs_iread_extents(tp, ip, whichfork);
1278         if (error)
1279                 return error;
1280
1281         if (!xfs_iext_lookup_extent_before(ip, ifp, last_block, &icur, &got))
1282                 *last_block = 0;
1283         return 0;
1284 }
1285
1286 int
1287 xfs_bmap_last_extent(
1288         struct xfs_trans        *tp,
1289         struct xfs_inode        *ip,
1290         int                     whichfork,
1291         struct xfs_bmbt_irec    *rec,
1292         int                     *is_empty)
1293 {
1294         struct xfs_ifork        *ifp = XFS_IFORK_PTR(ip, whichfork);
1295         struct xfs_iext_cursor  icur;
1296         int                     error;
1297
1298         error = xfs_iread_extents(tp, ip, whichfork);
1299         if (error)
1300                 return error;
1301
1302         xfs_iext_last(ifp, &icur);
1303         if (!xfs_iext_get_extent(ifp, &icur, rec))
1304                 *is_empty = 1;
1305         else
1306                 *is_empty = 0;
1307         return 0;
1308 }
1309
1310 /*
1311  * Check the last inode extent to determine whether this allocation will result
1312  * in blocks being allocated at the end of the file. When we allocate new data
1313  * blocks at the end of the file which do not start at the previous data block,
1314  * we will try to align the new blocks at stripe unit boundaries.
1315  *
1316  * Returns 1 in bma->aeof if the file (fork) is empty as any new write will be
1317  * at, or past the EOF.
1318  */
1319 STATIC int
1320 xfs_bmap_isaeof(
1321         struct xfs_bmalloca     *bma,
1322         int                     whichfork)
1323 {
1324         struct xfs_bmbt_irec    rec;
1325         int                     is_empty;
1326         int                     error;
1327
1328         bma->aeof = false;
1329         error = xfs_bmap_last_extent(NULL, bma->ip, whichfork, &rec,
1330                                      &is_empty);
1331         if (error)
1332                 return error;
1333
1334         if (is_empty) {
1335                 bma->aeof = true;
1336                 return 0;
1337         }
1338
1339         /*
1340          * Check if we are allocation or past the last extent, or at least into
1341          * the last delayed allocated extent.
1342          */
1343         bma->aeof = bma->offset >= rec.br_startoff + rec.br_blockcount ||
1344                 (bma->offset >= rec.br_startoff &&
1345                  isnullstartblock(rec.br_startblock));
1346         return 0;
1347 }
1348
1349 /*
1350  * Returns the file-relative block number of the first block past eof in
1351  * the file.  This is not based on i_size, it is based on the extent records.
1352  * Returns 0 for local files, as they do not have extent records.
1353  */
1354 int
1355 xfs_bmap_last_offset(
1356         struct xfs_inode        *ip,
1357         xfs_fileoff_t           *last_block,
1358         int                     whichfork)
1359 {
1360         struct xfs_ifork        *ifp = XFS_IFORK_PTR(ip, whichfork);
1361         struct xfs_bmbt_irec    rec;
1362         int                     is_empty;
1363         int                     error;
1364
1365         *last_block = 0;
1366
1367         if (ifp->if_format == XFS_DINODE_FMT_LOCAL)
1368                 return 0;
1369
1370         if (XFS_IS_CORRUPT(ip->i_mount, !xfs_ifork_has_extents(ifp)))
1371                 return -EFSCORRUPTED;
1372
1373         error = xfs_bmap_last_extent(NULL, ip, whichfork, &rec, &is_empty);
1374         if (error || is_empty)
1375                 return error;
1376
1377         *last_block = rec.br_startoff + rec.br_blockcount;
1378         return 0;
1379 }
1380
1381 /*
1382  * Extent tree manipulation functions used during allocation.
1383  */
1384
1385 /*
1386  * Convert a delayed allocation to a real allocation.
1387  */
1388 STATIC int                              /* error */
1389 xfs_bmap_add_extent_delay_real(
1390         struct xfs_bmalloca     *bma,
1391         int                     whichfork)
1392 {
1393         struct xfs_mount        *mp = bma->ip->i_mount;
1394         struct xfs_ifork        *ifp = XFS_IFORK_PTR(bma->ip, whichfork);
1395         struct xfs_bmbt_irec    *new = &bma->got;
1396         int                     error;  /* error return value */
1397         int                     i;      /* temp state */
1398         xfs_fileoff_t           new_endoff;     /* end offset of new entry */
1399         xfs_bmbt_irec_t         r[3];   /* neighbor extent entries */
1400                                         /* left is 0, right is 1, prev is 2 */
1401         int                     rval=0; /* return value (logging flags) */
1402         int                     state = xfs_bmap_fork_to_state(whichfork);
1403         xfs_filblks_t           da_new; /* new count del alloc blocks used */
1404         xfs_filblks_t           da_old; /* old count del alloc blocks used */
1405         xfs_filblks_t           temp=0; /* value for da_new calculations */
1406         int                     tmp_rval;       /* partial logging flags */
1407         struct xfs_bmbt_irec    old;
1408
1409         ASSERT(whichfork != XFS_ATTR_FORK);
1410         ASSERT(!isnullstartblock(new->br_startblock));
1411         ASSERT(!bma->cur ||
1412                (bma->cur->bc_ino.flags & XFS_BTCUR_BMBT_WASDEL));
1413
1414         XFS_STATS_INC(mp, xs_add_exlist);
1415
1416 #define LEFT            r[0]
1417 #define RIGHT           r[1]
1418 #define PREV            r[2]
1419
1420         /*
1421          * Set up a bunch of variables to make the tests simpler.
1422          */
1423         xfs_iext_get_extent(ifp, &bma->icur, &PREV);
1424         new_endoff = new->br_startoff + new->br_blockcount;
1425         ASSERT(isnullstartblock(PREV.br_startblock));
1426         ASSERT(PREV.br_startoff <= new->br_startoff);
1427         ASSERT(PREV.br_startoff + PREV.br_blockcount >= new_endoff);
1428
1429         da_old = startblockval(PREV.br_startblock);
1430         da_new = 0;
1431
1432         /*
1433          * Set flags determining what part of the previous delayed allocation
1434          * extent is being replaced by a real allocation.
1435          */
1436         if (PREV.br_startoff == new->br_startoff)
1437                 state |= BMAP_LEFT_FILLING;
1438         if (PREV.br_startoff + PREV.br_blockcount == new_endoff)
1439                 state |= BMAP_RIGHT_FILLING;
1440
1441         /*
1442          * Check and set flags if this segment has a left neighbor.
1443          * Don't set contiguous if the combined extent would be too large.
1444          */
1445         if (xfs_iext_peek_prev_extent(ifp, &bma->icur, &LEFT)) {
1446                 state |= BMAP_LEFT_VALID;
1447                 if (isnullstartblock(LEFT.br_startblock))
1448                         state |= BMAP_LEFT_DELAY;
1449         }
1450
1451         if ((state & BMAP_LEFT_VALID) && !(state & BMAP_LEFT_DELAY) &&
1452             LEFT.br_startoff + LEFT.br_blockcount == new->br_startoff &&
1453             LEFT.br_startblock + LEFT.br_blockcount == new->br_startblock &&
1454             LEFT.br_state == new->br_state &&
1455             LEFT.br_blockcount + new->br_blockcount <= MAXEXTLEN)
1456                 state |= BMAP_LEFT_CONTIG;
1457
1458         /*
1459          * Check and set flags if this segment has a right neighbor.
1460          * Don't set contiguous if the combined extent would be too large.
1461          * Also check for all-three-contiguous being too large.
1462          */
1463         if (xfs_iext_peek_next_extent(ifp, &bma->icur, &RIGHT)) {
1464                 state |= BMAP_RIGHT_VALID;
1465                 if (isnullstartblock(RIGHT.br_startblock))
1466                         state |= BMAP_RIGHT_DELAY;
1467         }
1468
1469         if ((state & BMAP_RIGHT_VALID) && !(state & BMAP_RIGHT_DELAY) &&
1470             new_endoff == RIGHT.br_startoff &&
1471             new->br_startblock + new->br_blockcount == RIGHT.br_startblock &&
1472             new->br_state == RIGHT.br_state &&
1473             new->br_blockcount + RIGHT.br_blockcount <= MAXEXTLEN &&
1474             ((state & (BMAP_LEFT_CONTIG | BMAP_LEFT_FILLING |
1475                        BMAP_RIGHT_FILLING)) !=
1476                       (BMAP_LEFT_CONTIG | BMAP_LEFT_FILLING |
1477                        BMAP_RIGHT_FILLING) ||
1478              LEFT.br_blockcount + new->br_blockcount + RIGHT.br_blockcount
1479                         <= MAXEXTLEN))
1480                 state |= BMAP_RIGHT_CONTIG;
1481
1482         error = 0;
1483         /*
1484          * Switch out based on the FILLING and CONTIG state bits.
1485          */
1486         switch (state & (BMAP_LEFT_FILLING | BMAP_LEFT_CONTIG |
1487                          BMAP_RIGHT_FILLING | BMAP_RIGHT_CONTIG)) {
1488         case BMAP_LEFT_FILLING | BMAP_LEFT_CONTIG |
1489              BMAP_RIGHT_FILLING | BMAP_RIGHT_CONTIG:
1490                 /*
1491                  * Filling in all of a previously delayed allocation extent.
1492                  * The left and right neighbors are both contiguous with new.
1493                  */
1494                 LEFT.br_blockcount += PREV.br_blockcount + RIGHT.br_blockcount;
1495
1496                 xfs_iext_remove(bma->ip, &bma->icur, state);
1497                 xfs_iext_remove(bma->ip, &bma->icur, state);
1498                 xfs_iext_prev(ifp, &bma->icur);
1499                 xfs_iext_update_extent(bma->ip, state, &bma->icur, &LEFT);
1500                 ifp->if_nextents--;
1501
1502                 if (bma->cur == NULL)
1503                         rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
1504                 else {
1505                         rval = XFS_ILOG_CORE;
1506                         error = xfs_bmbt_lookup_eq(bma->cur, &RIGHT, &i);
1507                         if (error)
1508                                 goto done;
1509                         if (XFS_IS_CORRUPT(mp, i != 1)) {
1510                                 error = -EFSCORRUPTED;
1511                                 goto done;
1512                         }
1513                         error = xfs_btree_delete(bma->cur, &i);
1514                         if (error)
1515                                 goto done;
1516                         if (XFS_IS_CORRUPT(mp, i != 1)) {
1517                                 error = -EFSCORRUPTED;
1518                                 goto done;
1519                         }
1520                         error = xfs_btree_decrement(bma->cur, 0, &i);
1521                         if (error)
1522                                 goto done;
1523                         if (XFS_IS_CORRUPT(mp, i != 1)) {
1524                                 error = -EFSCORRUPTED;
1525                                 goto done;
1526                         }
1527                         error = xfs_bmbt_update(bma->cur, &LEFT);
1528                         if (error)
1529                                 goto done;
1530                 }
1531                 break;
1532
1533         case BMAP_LEFT_FILLING | BMAP_RIGHT_FILLING | BMAP_LEFT_CONTIG:
1534                 /*
1535                  * Filling in all of a previously delayed allocation extent.
1536                  * The left neighbor is contiguous, the right is not.
1537                  */
1538                 old = LEFT;
1539                 LEFT.br_blockcount += PREV.br_blockcount;
1540
1541                 xfs_iext_remove(bma->ip, &bma->icur, state);
1542                 xfs_iext_prev(ifp, &bma->icur);
1543                 xfs_iext_update_extent(bma->ip, state, &bma->icur, &LEFT);
1544
1545                 if (bma->cur == NULL)
1546                         rval = XFS_ILOG_DEXT;
1547                 else {
1548                         rval = 0;
1549                         error = xfs_bmbt_lookup_eq(bma->cur, &old, &i);
1550                         if (error)
1551                                 goto done;
1552                         if (XFS_IS_CORRUPT(mp, i != 1)) {
1553                                 error = -EFSCORRUPTED;
1554                                 goto done;
1555                         }
1556                         error = xfs_bmbt_update(bma->cur, &LEFT);
1557                         if (error)
1558                                 goto done;
1559                 }
1560                 break;
1561
1562         case BMAP_LEFT_FILLING | BMAP_RIGHT_FILLING | BMAP_RIGHT_CONTIG:
1563                 /*
1564                  * Filling in all of a previously delayed allocation extent.
1565                  * The right neighbor is contiguous, the left is not. Take care
1566                  * with delay -> unwritten extent allocation here because the
1567                  * delalloc record we are overwriting is always written.
1568                  */
1569                 PREV.br_startblock = new->br_startblock;
1570                 PREV.br_blockcount += RIGHT.br_blockcount;
1571                 PREV.br_state = new->br_state;
1572
1573                 xfs_iext_next(ifp, &bma->icur);
1574                 xfs_iext_remove(bma->ip, &bma->icur, state);
1575                 xfs_iext_prev(ifp, &bma->icur);
1576                 xfs_iext_update_extent(bma->ip, state, &bma->icur, &PREV);
1577
1578                 if (bma->cur == NULL)
1579                         rval = XFS_ILOG_DEXT;
1580                 else {
1581                         rval = 0;
1582                         error = xfs_bmbt_lookup_eq(bma->cur, &RIGHT, &i);
1583                         if (error)
1584                                 goto done;
1585                         if (XFS_IS_CORRUPT(mp, i != 1)) {
1586                                 error = -EFSCORRUPTED;
1587                                 goto done;
1588                         }
1589                         error = xfs_bmbt_update(bma->cur, &PREV);
1590                         if (error)
1591                                 goto done;
1592                 }
1593                 break;
1594
1595         case BMAP_LEFT_FILLING | BMAP_RIGHT_FILLING:
1596                 /*
1597                  * Filling in all of a previously delayed allocation extent.
1598                  * Neither the left nor right neighbors are contiguous with
1599                  * the new one.
1600                  */
1601                 PREV.br_startblock = new->br_startblock;
1602                 PREV.br_state = new->br_state;
1603                 xfs_iext_update_extent(bma->ip, state, &bma->icur, &PREV);
1604                 ifp->if_nextents++;
1605
1606                 if (bma->cur == NULL)
1607                         rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
1608                 else {
1609                         rval = XFS_ILOG_CORE;
1610                         error = xfs_bmbt_lookup_eq(bma->cur, new, &i);
1611                         if (error)
1612                                 goto done;
1613                         if (XFS_IS_CORRUPT(mp, i != 0)) {
1614                                 error = -EFSCORRUPTED;
1615                                 goto done;
1616                         }
1617                         error = xfs_btree_insert(bma->cur, &i);
1618                         if (error)
1619                                 goto done;
1620                         if (XFS_IS_CORRUPT(mp, i != 1)) {
1621                                 error = -EFSCORRUPTED;
1622                                 goto done;
1623                         }
1624                 }
1625                 break;
1626
1627         case BMAP_LEFT_FILLING | BMAP_LEFT_CONTIG:
1628                 /*
1629                  * Filling in the first part of a previous delayed allocation.
1630                  * The left neighbor is contiguous.
1631                  */
1632                 old = LEFT;
1633                 temp = PREV.br_blockcount - new->br_blockcount;
1634                 da_new = XFS_FILBLKS_MIN(xfs_bmap_worst_indlen(bma->ip, temp),
1635                                 startblockval(PREV.br_startblock));
1636
1637                 LEFT.br_blockcount += new->br_blockcount;
1638
1639                 PREV.br_blockcount = temp;
1640                 PREV.br_startoff += new->br_blockcount;
1641                 PREV.br_startblock = nullstartblock(da_new);
1642
1643                 xfs_iext_update_extent(bma->ip, state, &bma->icur, &PREV);
1644                 xfs_iext_prev(ifp, &bma->icur);
1645                 xfs_iext_update_extent(bma->ip, state, &bma->icur, &LEFT);
1646
1647                 if (bma->cur == NULL)
1648                         rval = XFS_ILOG_DEXT;
1649                 else {
1650                         rval = 0;
1651                         error = xfs_bmbt_lookup_eq(bma->cur, &old, &i);
1652                         if (error)
1653                                 goto done;
1654                         if (XFS_IS_CORRUPT(mp, i != 1)) {
1655                                 error = -EFSCORRUPTED;
1656                                 goto done;
1657                         }
1658                         error = xfs_bmbt_update(bma->cur, &LEFT);
1659                         if (error)
1660                                 goto done;
1661                 }
1662                 break;
1663
1664         case BMAP_LEFT_FILLING:
1665                 /*
1666                  * Filling in the first part of a previous delayed allocation.
1667                  * The left neighbor is not contiguous.
1668                  */
1669                 xfs_iext_update_extent(bma->ip, state, &bma->icur, new);
1670                 ifp->if_nextents++;
1671
1672                 if (bma->cur == NULL)
1673                         rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
1674                 else {
1675                         rval = XFS_ILOG_CORE;
1676                         error = xfs_bmbt_lookup_eq(bma->cur, new, &i);
1677                         if (error)
1678                                 goto done;
1679                         if (XFS_IS_CORRUPT(mp, i != 0)) {
1680                                 error = -EFSCORRUPTED;
1681                                 goto done;
1682                         }
1683                         error = xfs_btree_insert(bma->cur, &i);
1684                         if (error)
1685                                 goto done;
1686                         if (XFS_IS_CORRUPT(mp, i != 1)) {
1687                                 error = -EFSCORRUPTED;
1688                                 goto done;
1689                         }
1690                 }
1691
1692                 if (xfs_bmap_needs_btree(bma->ip, whichfork)) {
1693                         error = xfs_bmap_extents_to_btree(bma->tp, bma->ip,
1694                                         &bma->cur, 1, &tmp_rval, whichfork);
1695                         rval |= tmp_rval;
1696                         if (error)
1697                                 goto done;
1698                 }
1699
1700                 temp = PREV.br_blockcount - new->br_blockcount;
1701                 da_new = XFS_FILBLKS_MIN(xfs_bmap_worst_indlen(bma->ip, temp),
1702                         startblockval(PREV.br_startblock) -
1703                         (bma->cur ? bma->cur->bc_ino.allocated : 0));
1704
1705                 PREV.br_startoff = new_endoff;
1706                 PREV.br_blockcount = temp;
1707                 PREV.br_startblock = nullstartblock(da_new);
1708                 xfs_iext_next(ifp, &bma->icur);
1709                 xfs_iext_insert(bma->ip, &bma->icur, &PREV, state);
1710                 xfs_iext_prev(ifp, &bma->icur);
1711                 break;
1712
1713         case BMAP_RIGHT_FILLING | BMAP_RIGHT_CONTIG:
1714                 /*
1715                  * Filling in the last part of a previous delayed allocation.
1716                  * The right neighbor is contiguous with the new allocation.
1717                  */
1718                 old = RIGHT;
1719                 RIGHT.br_startoff = new->br_startoff;
1720                 RIGHT.br_startblock = new->br_startblock;
1721                 RIGHT.br_blockcount += new->br_blockcount;
1722
1723                 if (bma->cur == NULL)
1724                         rval = XFS_ILOG_DEXT;
1725                 else {
1726                         rval = 0;
1727                         error = xfs_bmbt_lookup_eq(bma->cur, &old, &i);
1728                         if (error)
1729                                 goto done;
1730                         if (XFS_IS_CORRUPT(mp, i != 1)) {
1731                                 error = -EFSCORRUPTED;
1732                                 goto done;
1733                         }
1734                         error = xfs_bmbt_update(bma->cur, &RIGHT);
1735                         if (error)
1736                                 goto done;
1737                 }
1738
1739                 temp = PREV.br_blockcount - new->br_blockcount;
1740                 da_new = XFS_FILBLKS_MIN(xfs_bmap_worst_indlen(bma->ip, temp),
1741                         startblockval(PREV.br_startblock));
1742
1743                 PREV.br_blockcount = temp;
1744                 PREV.br_startblock = nullstartblock(da_new);
1745
1746                 xfs_iext_update_extent(bma->ip, state, &bma->icur, &PREV);
1747                 xfs_iext_next(ifp, &bma->icur);
1748                 xfs_iext_update_extent(bma->ip, state, &bma->icur, &RIGHT);
1749                 break;
1750
1751         case BMAP_RIGHT_FILLING:
1752                 /*
1753                  * Filling in the last part of a previous delayed allocation.
1754                  * The right neighbor is not contiguous.
1755                  */
1756                 xfs_iext_update_extent(bma->ip, state, &bma->icur, new);
1757                 ifp->if_nextents++;
1758
1759                 if (bma->cur == NULL)
1760                         rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
1761                 else {
1762                         rval = XFS_ILOG_CORE;
1763                         error = xfs_bmbt_lookup_eq(bma->cur, new, &i);
1764                         if (error)
1765                                 goto done;
1766                         if (XFS_IS_CORRUPT(mp, i != 0)) {
1767                                 error = -EFSCORRUPTED;
1768                                 goto done;
1769                         }
1770                         error = xfs_btree_insert(bma->cur, &i);
1771                         if (error)
1772                                 goto done;
1773                         if (XFS_IS_CORRUPT(mp, i != 1)) {
1774                                 error = -EFSCORRUPTED;
1775                                 goto done;
1776                         }
1777                 }
1778
1779                 if (xfs_bmap_needs_btree(bma->ip, whichfork)) {
1780                         error = xfs_bmap_extents_to_btree(bma->tp, bma->ip,
1781                                 &bma->cur, 1, &tmp_rval, whichfork);
1782                         rval |= tmp_rval;
1783                         if (error)
1784                                 goto done;
1785                 }
1786
1787                 temp = PREV.br_blockcount - new->br_blockcount;
1788                 da_new = XFS_FILBLKS_MIN(xfs_bmap_worst_indlen(bma->ip, temp),
1789                         startblockval(PREV.br_startblock) -
1790                         (bma->cur ? bma->cur->bc_ino.allocated : 0));
1791
1792                 PREV.br_startblock = nullstartblock(da_new);
1793                 PREV.br_blockcount = temp;
1794                 xfs_iext_insert(bma->ip, &bma->icur, &PREV, state);
1795                 xfs_iext_next(ifp, &bma->icur);
1796                 break;
1797
1798         case 0:
1799                 /*
1800                  * Filling in the middle part of a previous delayed allocation.
1801                  * Contiguity is impossible here.
1802                  * This case is avoided almost all the time.
1803                  *
1804                  * We start with a delayed allocation:
1805                  *
1806                  * +ddddddddddddddddddddddddddddddddddddddddddddddddddddddd+
1807                  *  PREV @ idx
1808                  *
1809                  * and we are allocating:
1810                  *                     +rrrrrrrrrrrrrrrrr+
1811                  *                            new
1812                  *
1813                  * and we set it up for insertion as:
1814                  * +ddddddddddddddddddd+rrrrrrrrrrrrrrrrr+ddddddddddddddddd+
1815                  *                            new
1816                  *  PREV @ idx          LEFT              RIGHT
1817                  *                      inserted at idx + 1
1818                  */
1819                 old = PREV;
1820
1821                 /* LEFT is the new middle */
1822                 LEFT = *new;
1823
1824                 /* RIGHT is the new right */
1825                 RIGHT.br_state = PREV.br_state;
1826                 RIGHT.br_startoff = new_endoff;
1827                 RIGHT.br_blockcount =
1828                         PREV.br_startoff + PREV.br_blockcount - new_endoff;
1829                 RIGHT.br_startblock =
1830                         nullstartblock(xfs_bmap_worst_indlen(bma->ip,
1831                                         RIGHT.br_blockcount));
1832
1833                 /* truncate PREV */
1834                 PREV.br_blockcount = new->br_startoff - PREV.br_startoff;
1835                 PREV.br_startblock =
1836                         nullstartblock(xfs_bmap_worst_indlen(bma->ip,
1837                                         PREV.br_blockcount));
1838                 xfs_iext_update_extent(bma->ip, state, &bma->icur, &PREV);
1839
1840                 xfs_iext_next(ifp, &bma->icur);
1841                 xfs_iext_insert(bma->ip, &bma->icur, &RIGHT, state);
1842                 xfs_iext_insert(bma->ip, &bma->icur, &LEFT, state);
1843                 ifp->if_nextents++;
1844
1845                 if (bma->cur == NULL)
1846                         rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
1847                 else {
1848                         rval = XFS_ILOG_CORE;
1849                         error = xfs_bmbt_lookup_eq(bma->cur, new, &i);
1850                         if (error)
1851                                 goto done;
1852                         if (XFS_IS_CORRUPT(mp, i != 0)) {
1853                                 error = -EFSCORRUPTED;
1854                                 goto done;
1855                         }
1856                         error = xfs_btree_insert(bma->cur, &i);
1857                         if (error)
1858                                 goto done;
1859                         if (XFS_IS_CORRUPT(mp, i != 1)) {
1860                                 error = -EFSCORRUPTED;
1861                                 goto done;
1862                         }
1863                 }
1864
1865                 if (xfs_bmap_needs_btree(bma->ip, whichfork)) {
1866                         error = xfs_bmap_extents_to_btree(bma->tp, bma->ip,
1867                                         &bma->cur, 1, &tmp_rval, whichfork);
1868                         rval |= tmp_rval;
1869                         if (error)
1870                                 goto done;
1871                 }
1872
1873                 da_new = startblockval(PREV.br_startblock) +
1874                          startblockval(RIGHT.br_startblock);
1875                 break;
1876
1877         case BMAP_LEFT_FILLING | BMAP_LEFT_CONTIG | BMAP_RIGHT_CONTIG:
1878         case BMAP_RIGHT_FILLING | BMAP_LEFT_CONTIG | BMAP_RIGHT_CONTIG:
1879         case BMAP_LEFT_FILLING | BMAP_RIGHT_CONTIG:
1880         case BMAP_RIGHT_FILLING | BMAP_LEFT_CONTIG:
1881         case BMAP_LEFT_CONTIG | BMAP_RIGHT_CONTIG:
1882         case BMAP_LEFT_CONTIG:
1883         case BMAP_RIGHT_CONTIG:
1884                 /*
1885                  * These cases are all impossible.
1886                  */
1887                 ASSERT(0);
1888         }
1889
1890         /* add reverse mapping unless caller opted out */
1891         if (!(bma->flags & XFS_BMAPI_NORMAP))
1892                 xfs_rmap_map_extent(bma->tp, bma->ip, whichfork, new);
1893
1894         /* convert to a btree if necessary */
1895         if (xfs_bmap_needs_btree(bma->ip, whichfork)) {
1896                 int     tmp_logflags;   /* partial log flag return val */
1897
1898                 ASSERT(bma->cur == NULL);
1899                 error = xfs_bmap_extents_to_btree(bma->tp, bma->ip,
1900                                 &bma->cur, da_old > 0, &tmp_logflags,
1901                                 whichfork);
1902                 bma->logflags |= tmp_logflags;
1903                 if (error)
1904                         goto done;
1905         }
1906
1907         if (da_new != da_old)
1908                 xfs_mod_delalloc(mp, (int64_t)da_new - da_old);
1909
1910         if (bma->cur) {
1911                 da_new += bma->cur->bc_ino.allocated;
1912                 bma->cur->bc_ino.allocated = 0;
1913         }
1914
1915         /* adjust for changes in reserved delayed indirect blocks */
1916         if (da_new != da_old) {
1917                 ASSERT(state == 0 || da_new < da_old);
1918                 error = xfs_mod_fdblocks(mp, (int64_t)(da_old - da_new),
1919                                 false);
1920         }
1921
1922         xfs_bmap_check_leaf_extents(bma->cur, bma->ip, whichfork);
1923 done:
1924         if (whichfork != XFS_COW_FORK)
1925                 bma->logflags |= rval;
1926         return error;
1927 #undef  LEFT
1928 #undef  RIGHT
1929 #undef  PREV
1930 }
1931
1932 /*
1933  * Convert an unwritten allocation to a real allocation or vice versa.
1934  */
1935 int                                     /* error */
1936 xfs_bmap_add_extent_unwritten_real(
1937         struct xfs_trans        *tp,
1938         xfs_inode_t             *ip,    /* incore inode pointer */
1939         int                     whichfork,
1940         struct xfs_iext_cursor  *icur,
1941         struct xfs_btree_cur    **curp, /* if *curp is null, not a btree */
1942         xfs_bmbt_irec_t         *new,   /* new data to add to file extents */
1943         int                     *logflagsp) /* inode logging flags */
1944 {
1945         struct xfs_btree_cur    *cur;   /* btree cursor */
1946         int                     error;  /* error return value */
1947         int                     i;      /* temp state */
1948         struct xfs_ifork        *ifp;   /* inode fork pointer */
1949         xfs_fileoff_t           new_endoff;     /* end offset of new entry */
1950         xfs_bmbt_irec_t         r[3];   /* neighbor extent entries */
1951                                         /* left is 0, right is 1, prev is 2 */
1952         int                     rval=0; /* return value (logging flags) */
1953         int                     state = xfs_bmap_fork_to_state(whichfork);
1954         struct xfs_mount        *mp = ip->i_mount;
1955         struct xfs_bmbt_irec    old;
1956
1957         *logflagsp = 0;
1958
1959         cur = *curp;
1960         ifp = XFS_IFORK_PTR(ip, whichfork);
1961
1962         ASSERT(!isnullstartblock(new->br_startblock));
1963
1964         XFS_STATS_INC(mp, xs_add_exlist);
1965
1966 #define LEFT            r[0]
1967 #define RIGHT           r[1]
1968 #define PREV            r[2]
1969
1970         /*
1971          * Set up a bunch of variables to make the tests simpler.
1972          */
1973         error = 0;
1974         xfs_iext_get_extent(ifp, icur, &PREV);
1975         ASSERT(new->br_state != PREV.br_state);
1976         new_endoff = new->br_startoff + new->br_blockcount;
1977         ASSERT(PREV.br_startoff <= new->br_startoff);
1978         ASSERT(PREV.br_startoff + PREV.br_blockcount >= new_endoff);
1979
1980         /*
1981          * Set flags determining what part of the previous oldext allocation
1982          * extent is being replaced by a newext allocation.
1983          */
1984         if (PREV.br_startoff == new->br_startoff)
1985                 state |= BMAP_LEFT_FILLING;
1986         if (PREV.br_startoff + PREV.br_blockcount == new_endoff)
1987                 state |= BMAP_RIGHT_FILLING;
1988
1989         /*
1990          * Check and set flags if this segment has a left neighbor.
1991          * Don't set contiguous if the combined extent would be too large.
1992          */
1993         if (xfs_iext_peek_prev_extent(ifp, icur, &LEFT)) {
1994                 state |= BMAP_LEFT_VALID;
1995                 if (isnullstartblock(LEFT.br_startblock))
1996                         state |= BMAP_LEFT_DELAY;
1997         }
1998
1999         if ((state & BMAP_LEFT_VALID) && !(state & BMAP_LEFT_DELAY) &&
2000             LEFT.br_startoff + LEFT.br_blockcount == new->br_startoff &&
2001             LEFT.br_startblock + LEFT.br_blockcount == new->br_startblock &&
2002             LEFT.br_state == new->br_state &&
2003             LEFT.br_blockcount + new->br_blockcount <= MAXEXTLEN)
2004                 state |= BMAP_LEFT_CONTIG;
2005
2006         /*
2007          * Check and set flags if this segment has a right neighbor.
2008          * Don't set contiguous if the combined extent would be too large.
2009          * Also check for all-three-contiguous being too large.
2010          */
2011         if (xfs_iext_peek_next_extent(ifp, icur, &RIGHT)) {
2012                 state |= BMAP_RIGHT_VALID;
2013                 if (isnullstartblock(RIGHT.br_startblock))
2014                         state |= BMAP_RIGHT_DELAY;
2015         }
2016
2017         if ((state & BMAP_RIGHT_VALID) && !(state & BMAP_RIGHT_DELAY) &&
2018             new_endoff == RIGHT.br_startoff &&
2019             new->br_startblock + new->br_blockcount == RIGHT.br_startblock &&
2020             new->br_state == RIGHT.br_state &&
2021             new->br_blockcount + RIGHT.br_blockcount <= MAXEXTLEN &&
2022             ((state & (BMAP_LEFT_CONTIG | BMAP_LEFT_FILLING |
2023                        BMAP_RIGHT_FILLING)) !=
2024                       (BMAP_LEFT_CONTIG | BMAP_LEFT_FILLING |
2025                        BMAP_RIGHT_FILLING) ||
2026              LEFT.br_blockcount + new->br_blockcount + RIGHT.br_blockcount
2027                         <= MAXEXTLEN))
2028                 state |= BMAP_RIGHT_CONTIG;
2029
2030         /*
2031          * Switch out based on the FILLING and CONTIG state bits.
2032          */
2033         switch (state & (BMAP_LEFT_FILLING | BMAP_LEFT_CONTIG |
2034                          BMAP_RIGHT_FILLING | BMAP_RIGHT_CONTIG)) {
2035         case BMAP_LEFT_FILLING | BMAP_LEFT_CONTIG |
2036              BMAP_RIGHT_FILLING | BMAP_RIGHT_CONTIG:
2037                 /*
2038                  * Setting all of a previous oldext extent to newext.
2039                  * The left and right neighbors are both contiguous with new.
2040                  */
2041                 LEFT.br_blockcount += PREV.br_blockcount + RIGHT.br_blockcount;
2042
2043                 xfs_iext_remove(ip, icur, state);
2044                 xfs_iext_remove(ip, icur, state);
2045                 xfs_iext_prev(ifp, icur);
2046                 xfs_iext_update_extent(ip, state, icur, &LEFT);
2047                 ifp->if_nextents -= 2;
2048                 if (cur == NULL)
2049                         rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
2050                 else {
2051                         rval = XFS_ILOG_CORE;
2052                         error = xfs_bmbt_lookup_eq(cur, &RIGHT, &i);
2053                         if (error)
2054                                 goto done;
2055                         if (XFS_IS_CORRUPT(mp, i != 1)) {
2056                                 error = -EFSCORRUPTED;
2057                                 goto done;
2058                         }
2059                         if ((error = xfs_btree_delete(cur, &i)))
2060                                 goto done;
2061                         if (XFS_IS_CORRUPT(mp, i != 1)) {
2062                                 error = -EFSCORRUPTED;
2063                                 goto done;
2064                         }
2065                         if ((error = xfs_btree_decrement(cur, 0, &i)))
2066                                 goto done;
2067                         if (XFS_IS_CORRUPT(mp, i != 1)) {
2068                                 error = -EFSCORRUPTED;
2069                                 goto done;
2070                         }
2071                         if ((error = xfs_btree_delete(cur, &i)))
2072                                 goto done;
2073                         if (XFS_IS_CORRUPT(mp, i != 1)) {
2074                                 error = -EFSCORRUPTED;
2075                                 goto done;
2076                         }
2077                         if ((error = xfs_btree_decrement(cur, 0, &i)))
2078                                 goto done;
2079                         if (XFS_IS_CORRUPT(mp, i != 1)) {
2080                                 error = -EFSCORRUPTED;
2081                                 goto done;
2082                         }
2083                         error = xfs_bmbt_update(cur, &LEFT);
2084                         if (error)
2085                                 goto done;
2086                 }
2087                 break;
2088
2089         case BMAP_LEFT_FILLING | BMAP_RIGHT_FILLING | BMAP_LEFT_CONTIG:
2090                 /*
2091                  * Setting all of a previous oldext extent to newext.
2092                  * The left neighbor is contiguous, the right is not.
2093                  */
2094                 LEFT.br_blockcount += PREV.br_blockcount;
2095
2096                 xfs_iext_remove(ip, icur, state);
2097                 xfs_iext_prev(ifp, icur);
2098                 xfs_iext_update_extent(ip, state, icur, &LEFT);
2099                 ifp->if_nextents--;
2100                 if (cur == NULL)
2101                         rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
2102                 else {
2103                         rval = XFS_ILOG_CORE;
2104                         error = xfs_bmbt_lookup_eq(cur, &PREV, &i);
2105                         if (error)
2106                                 goto done;
2107                         if (XFS_IS_CORRUPT(mp, i != 1)) {
2108                                 error = -EFSCORRUPTED;
2109                                 goto done;
2110                         }
2111                         if ((error = xfs_btree_delete(cur, &i)))
2112                                 goto done;
2113                         if (XFS_IS_CORRUPT(mp, i != 1)) {
2114                                 error = -EFSCORRUPTED;
2115                                 goto done;
2116                         }
2117                         if ((error = xfs_btree_decrement(cur, 0, &i)))
2118                                 goto done;
2119                         if (XFS_IS_CORRUPT(mp, i != 1)) {
2120                                 error = -EFSCORRUPTED;
2121                                 goto done;
2122                         }
2123                         error = xfs_bmbt_update(cur, &LEFT);
2124                         if (error)
2125                                 goto done;
2126                 }
2127                 break;
2128
2129         case BMAP_LEFT_FILLING | BMAP_RIGHT_FILLING | BMAP_RIGHT_CONTIG:
2130                 /*
2131                  * Setting all of a previous oldext extent to newext.
2132                  * The right neighbor is contiguous, the left is not.
2133                  */
2134                 PREV.br_blockcount += RIGHT.br_blockcount;
2135                 PREV.br_state = new->br_state;
2136
2137                 xfs_iext_next(ifp, icur);
2138                 xfs_iext_remove(ip, icur, state);
2139                 xfs_iext_prev(ifp, icur);
2140                 xfs_iext_update_extent(ip, state, icur, &PREV);
2141                 ifp->if_nextents--;
2142
2143                 if (cur == NULL)
2144                         rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
2145                 else {
2146                         rval = XFS_ILOG_CORE;
2147                         error = xfs_bmbt_lookup_eq(cur, &RIGHT, &i);
2148                         if (error)
2149                                 goto done;
2150                         if (XFS_IS_CORRUPT(mp, i != 1)) {
2151                                 error = -EFSCORRUPTED;
2152                                 goto done;
2153                         }
2154                         if ((error = xfs_btree_delete(cur, &i)))
2155                                 goto done;
2156                         if (XFS_IS_CORRUPT(mp, i != 1)) {
2157                                 error = -EFSCORRUPTED;
2158                                 goto done;
2159                         }
2160                         if ((error = xfs_btree_decrement(cur, 0, &i)))
2161                                 goto done;
2162                         if (XFS_IS_CORRUPT(mp, i != 1)) {
2163                                 error = -EFSCORRUPTED;
2164                                 goto done;
2165                         }
2166                         error = xfs_bmbt_update(cur, &PREV);
2167                         if (error)
2168                                 goto done;
2169                 }
2170                 break;
2171
2172         case BMAP_LEFT_FILLING | BMAP_RIGHT_FILLING:
2173                 /*
2174                  * Setting all of a previous oldext extent to newext.
2175                  * Neither the left nor right neighbors are contiguous with
2176                  * the new one.
2177                  */
2178                 PREV.br_state = new->br_state;
2179                 xfs_iext_update_extent(ip, state, icur, &PREV);
2180
2181                 if (cur == NULL)
2182                         rval = XFS_ILOG_DEXT;
2183                 else {
2184                         rval = 0;
2185                         error = xfs_bmbt_lookup_eq(cur, new, &i);
2186                         if (error)
2187                                 goto done;
2188                         if (XFS_IS_CORRUPT(mp, i != 1)) {
2189                                 error = -EFSCORRUPTED;
2190                                 goto done;
2191                         }
2192                         error = xfs_bmbt_update(cur, &PREV);
2193                         if (error)
2194                                 goto done;
2195                 }
2196                 break;
2197
2198         case BMAP_LEFT_FILLING | BMAP_LEFT_CONTIG:
2199                 /*
2200                  * Setting the first part of a previous oldext extent to newext.
2201                  * The left neighbor is contiguous.
2202                  */
2203                 LEFT.br_blockcount += new->br_blockcount;
2204
2205                 old = PREV;
2206                 PREV.br_startoff += new->br_blockcount;
2207                 PREV.br_startblock += new->br_blockcount;
2208                 PREV.br_blockcount -= new->br_blockcount;
2209
2210                 xfs_iext_update_extent(ip, state, icur, &PREV);
2211                 xfs_iext_prev(ifp, icur);
2212                 xfs_iext_update_extent(ip, state, icur, &LEFT);
2213
2214                 if (cur == NULL)
2215                         rval = XFS_ILOG_DEXT;
2216                 else {
2217                         rval = 0;
2218                         error = xfs_bmbt_lookup_eq(cur, &old, &i);
2219                         if (error)
2220                                 goto done;
2221                         if (XFS_IS_CORRUPT(mp, i != 1)) {
2222                                 error = -EFSCORRUPTED;
2223                                 goto done;
2224                         }
2225                         error = xfs_bmbt_update(cur, &PREV);
2226                         if (error)
2227                                 goto done;
2228                         error = xfs_btree_decrement(cur, 0, &i);
2229                         if (error)
2230                                 goto done;
2231                         error = xfs_bmbt_update(cur, &LEFT);
2232                         if (error)
2233                                 goto done;
2234                 }
2235                 break;
2236
2237         case BMAP_LEFT_FILLING:
2238                 /*
2239                  * Setting the first part of a previous oldext extent to newext.
2240                  * The left neighbor is not contiguous.
2241                  */
2242                 old = PREV;
2243                 PREV.br_startoff += new->br_blockcount;
2244                 PREV.br_startblock += new->br_blockcount;
2245                 PREV.br_blockcount -= new->br_blockcount;
2246
2247                 xfs_iext_update_extent(ip, state, icur, &PREV);
2248                 xfs_iext_insert(ip, icur, new, state);
2249                 ifp->if_nextents++;
2250
2251                 if (cur == NULL)
2252                         rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
2253                 else {
2254                         rval = XFS_ILOG_CORE;
2255                         error = xfs_bmbt_lookup_eq(cur, &old, &i);
2256                         if (error)
2257                                 goto done;
2258                         if (XFS_IS_CORRUPT(mp, i != 1)) {
2259                                 error = -EFSCORRUPTED;
2260                                 goto done;
2261                         }
2262                         error = xfs_bmbt_update(cur, &PREV);
2263                         if (error)
2264                                 goto done;
2265                         cur->bc_rec.b = *new;
2266                         if ((error = xfs_btree_insert(cur, &i)))
2267                                 goto done;
2268                         if (XFS_IS_CORRUPT(mp, i != 1)) {
2269                                 error = -EFSCORRUPTED;
2270                                 goto done;
2271                         }
2272                 }
2273                 break;
2274
2275         case BMAP_RIGHT_FILLING | BMAP_RIGHT_CONTIG:
2276                 /*
2277                  * Setting the last part of a previous oldext extent to newext.
2278                  * The right neighbor is contiguous with the new allocation.
2279                  */
2280                 old = PREV;
2281                 PREV.br_blockcount -= new->br_blockcount;
2282
2283                 RIGHT.br_startoff = new->br_startoff;
2284                 RIGHT.br_startblock = new->br_startblock;
2285                 RIGHT.br_blockcount += new->br_blockcount;
2286
2287                 xfs_iext_update_extent(ip, state, icur, &PREV);
2288                 xfs_iext_next(ifp, icur);
2289                 xfs_iext_update_extent(ip, state, icur, &RIGHT);
2290
2291                 if (cur == NULL)
2292                         rval = XFS_ILOG_DEXT;
2293                 else {
2294                         rval = 0;
2295                         error = xfs_bmbt_lookup_eq(cur, &old, &i);
2296                         if (error)
2297                                 goto done;
2298                         if (XFS_IS_CORRUPT(mp, i != 1)) {
2299                                 error = -EFSCORRUPTED;
2300                                 goto done;
2301                         }
2302                         error = xfs_bmbt_update(cur, &PREV);
2303                         if (error)
2304                                 goto done;
2305                         error = xfs_btree_increment(cur, 0, &i);
2306                         if (error)
2307                                 goto done;
2308                         error = xfs_bmbt_update(cur, &RIGHT);
2309                         if (error)
2310                                 goto done;
2311                 }
2312                 break;
2313
2314         case BMAP_RIGHT_FILLING:
2315                 /*
2316                  * Setting the last part of a previous oldext extent to newext.
2317                  * The right neighbor is not contiguous.
2318                  */
2319                 old = PREV;
2320                 PREV.br_blockcount -= new->br_blockcount;
2321
2322                 xfs_iext_update_extent(ip, state, icur, &PREV);
2323                 xfs_iext_next(ifp, icur);
2324                 xfs_iext_insert(ip, icur, new, state);
2325                 ifp->if_nextents++;
2326
2327                 if (cur == NULL)
2328                         rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
2329                 else {
2330                         rval = XFS_ILOG_CORE;
2331                         error = xfs_bmbt_lookup_eq(cur, &old, &i);
2332                         if (error)
2333                                 goto done;
2334                         if (XFS_IS_CORRUPT(mp, i != 1)) {
2335                                 error = -EFSCORRUPTED;
2336                                 goto done;
2337                         }
2338                         error = xfs_bmbt_update(cur, &PREV);
2339                         if (error)
2340                                 goto done;
2341                         error = xfs_bmbt_lookup_eq(cur, new, &i);
2342                         if (error)
2343                                 goto done;
2344                         if (XFS_IS_CORRUPT(mp, i != 0)) {
2345                                 error = -EFSCORRUPTED;
2346                                 goto done;
2347                         }
2348                         if ((error = xfs_btree_insert(cur, &i)))
2349                                 goto done;
2350                         if (XFS_IS_CORRUPT(mp, i != 1)) {
2351                                 error = -EFSCORRUPTED;
2352                                 goto done;
2353                         }
2354                 }
2355                 break;
2356
2357         case 0:
2358                 /*
2359                  * Setting the middle part of a previous oldext extent to
2360                  * newext.  Contiguity is impossible here.
2361                  * One extent becomes three extents.
2362                  */
2363                 old = PREV;
2364                 PREV.br_blockcount = new->br_startoff - PREV.br_startoff;
2365
2366                 r[0] = *new;
2367                 r[1].br_startoff = new_endoff;
2368                 r[1].br_blockcount =
2369                         old.br_startoff + old.br_blockcount - new_endoff;
2370                 r[1].br_startblock = new->br_startblock + new->br_blockcount;
2371                 r[1].br_state = PREV.br_state;
2372
2373                 xfs_iext_update_extent(ip, state, icur, &PREV);
2374                 xfs_iext_next(ifp, icur);
2375                 xfs_iext_insert(ip, icur, &r[1], state);
2376                 xfs_iext_insert(ip, icur, &r[0], state);
2377                 ifp->if_nextents += 2;
2378
2379                 if (cur == NULL)
2380                         rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
2381                 else {
2382                         rval = XFS_ILOG_CORE;
2383                         error = xfs_bmbt_lookup_eq(cur, &old, &i);
2384                         if (error)
2385                                 goto done;
2386                         if (XFS_IS_CORRUPT(mp, i != 1)) {
2387                                 error = -EFSCORRUPTED;
2388                                 goto done;
2389                         }
2390                         /* new right extent - oldext */
2391                         error = xfs_bmbt_update(cur, &r[1]);
2392                         if (error)
2393                                 goto done;
2394                         /* new left extent - oldext */
2395                         cur->bc_rec.b = PREV;
2396                         if ((error = xfs_btree_insert(cur, &i)))
2397                                 goto done;
2398                         if (XFS_IS_CORRUPT(mp, i != 1)) {
2399                                 error = -EFSCORRUPTED;
2400                                 goto done;
2401                         }
2402                         /*
2403                          * Reset the cursor to the position of the new extent
2404                          * we are about to insert as we can't trust it after
2405                          * the previous insert.
2406                          */
2407                         error = xfs_bmbt_lookup_eq(cur, new, &i);
2408                         if (error)
2409                                 goto done;
2410                         if (XFS_IS_CORRUPT(mp, i != 0)) {
2411                                 error = -EFSCORRUPTED;
2412                                 goto done;
2413                         }
2414                         /* new middle extent - newext */
2415                         if ((error = xfs_btree_insert(cur, &i)))
2416                                 goto done;
2417                         if (XFS_IS_CORRUPT(mp, i != 1)) {
2418                                 error = -EFSCORRUPTED;
2419                                 goto done;
2420                         }
2421                 }
2422                 break;
2423
2424         case BMAP_LEFT_FILLING | BMAP_LEFT_CONTIG | BMAP_RIGHT_CONTIG:
2425         case BMAP_RIGHT_FILLING | BMAP_LEFT_CONTIG | BMAP_RIGHT_CONTIG:
2426         case BMAP_LEFT_FILLING | BMAP_RIGHT_CONTIG:
2427         case BMAP_RIGHT_FILLING | BMAP_LEFT_CONTIG:
2428         case BMAP_LEFT_CONTIG | BMAP_RIGHT_CONTIG:
2429         case BMAP_LEFT_CONTIG:
2430         case BMAP_RIGHT_CONTIG:
2431                 /*
2432                  * These cases are all impossible.
2433                  */
2434                 ASSERT(0);
2435         }
2436
2437         /* update reverse mappings */
2438         xfs_rmap_convert_extent(mp, tp, ip, whichfork, new);
2439
2440         /* convert to a btree if necessary */
2441         if (xfs_bmap_needs_btree(ip, whichfork)) {
2442                 int     tmp_logflags;   /* partial log flag return val */
2443
2444                 ASSERT(cur == NULL);
2445                 error = xfs_bmap_extents_to_btree(tp, ip, &cur, 0,
2446                                 &tmp_logflags, whichfork);
2447                 *logflagsp |= tmp_logflags;
2448                 if (error)
2449                         goto done;
2450         }
2451
2452         /* clear out the allocated field, done with it now in any case. */
2453         if (cur) {
2454                 cur->bc_ino.allocated = 0;
2455                 *curp = cur;
2456         }
2457
2458         xfs_bmap_check_leaf_extents(*curp, ip, whichfork);
2459 done:
2460         *logflagsp |= rval;
2461         return error;
2462 #undef  LEFT
2463 #undef  RIGHT
2464 #undef  PREV
2465 }
2466
2467 /*
2468  * Convert a hole to a delayed allocation.
2469  */
2470 STATIC void
2471 xfs_bmap_add_extent_hole_delay(
2472         xfs_inode_t             *ip,    /* incore inode pointer */
2473         int                     whichfork,
2474         struct xfs_iext_cursor  *icur,
2475         xfs_bmbt_irec_t         *new)   /* new data to add to file extents */
2476 {
2477         struct xfs_ifork        *ifp;   /* inode fork pointer */
2478         xfs_bmbt_irec_t         left;   /* left neighbor extent entry */
2479         xfs_filblks_t           newlen=0;       /* new indirect size */
2480         xfs_filblks_t           oldlen=0;       /* old indirect size */
2481         xfs_bmbt_irec_t         right;  /* right neighbor extent entry */
2482         int                     state = xfs_bmap_fork_to_state(whichfork);
2483         xfs_filblks_t           temp;    /* temp for indirect calculations */
2484
2485         ifp = XFS_IFORK_PTR(ip, whichfork);
2486         ASSERT(isnullstartblock(new->br_startblock));
2487
2488         /*
2489          * Check and set flags if this segment has a left neighbor
2490          */
2491         if (xfs_iext_peek_prev_extent(ifp, icur, &left)) {
2492                 state |= BMAP_LEFT_VALID;
2493                 if (isnullstartblock(left.br_startblock))
2494                         state |= BMAP_LEFT_DELAY;
2495         }
2496
2497         /*
2498          * Check and set flags if the current (right) segment exists.
2499          * If it doesn't exist, we're converting the hole at end-of-file.
2500          */
2501         if (xfs_iext_get_extent(ifp, icur, &right)) {
2502                 state |= BMAP_RIGHT_VALID;
2503                 if (isnullstartblock(right.br_startblock))
2504                         state |= BMAP_RIGHT_DELAY;
2505         }
2506
2507         /*
2508          * Set contiguity flags on the left and right neighbors.
2509          * Don't let extents get too large, even if the pieces are contiguous.
2510          */
2511         if ((state & BMAP_LEFT_VALID) && (state & BMAP_LEFT_DELAY) &&
2512             left.br_startoff + left.br_blockcount == new->br_startoff &&
2513             left.br_blockcount + new->br_blockcount <= MAXEXTLEN)
2514                 state |= BMAP_LEFT_CONTIG;
2515
2516         if ((state & BMAP_RIGHT_VALID) && (state & BMAP_RIGHT_DELAY) &&
2517             new->br_startoff + new->br_blockcount == right.br_startoff &&
2518             new->br_blockcount + right.br_blockcount <= MAXEXTLEN &&
2519             (!(state & BMAP_LEFT_CONTIG) ||
2520              (left.br_blockcount + new->br_blockcount +
2521               right.br_blockcount <= MAXEXTLEN)))
2522                 state |= BMAP_RIGHT_CONTIG;
2523
2524         /*
2525          * Switch out based on the contiguity flags.
2526          */
2527         switch (state & (BMAP_LEFT_CONTIG | BMAP_RIGHT_CONTIG)) {
2528         case BMAP_LEFT_CONTIG | BMAP_RIGHT_CONTIG:
2529                 /*
2530                  * New allocation is contiguous with delayed allocations
2531                  * on the left and on the right.
2532                  * Merge all three into a single extent record.
2533                  */
2534                 temp = left.br_blockcount + new->br_blockcount +
2535                         right.br_blockcount;
2536
2537                 oldlen = startblockval(left.br_startblock) +
2538                         startblockval(new->br_startblock) +
2539                         startblockval(right.br_startblock);
2540                 newlen = XFS_FILBLKS_MIN(xfs_bmap_worst_indlen(ip, temp),
2541                                          oldlen);
2542                 left.br_startblock = nullstartblock(newlen);
2543                 left.br_blockcount = temp;
2544
2545                 xfs_iext_remove(ip, icur, state);
2546                 xfs_iext_prev(ifp, icur);
2547                 xfs_iext_update_extent(ip, state, icur, &left);
2548                 break;
2549
2550         case BMAP_LEFT_CONTIG:
2551                 /*
2552                  * New allocation is contiguous with a delayed allocation
2553                  * on the left.
2554                  * Merge the new allocation with the left neighbor.
2555                  */
2556                 temp = left.br_blockcount + new->br_blockcount;
2557
2558                 oldlen = startblockval(left.br_startblock) +
2559                         startblockval(new->br_startblock);
2560                 newlen = XFS_FILBLKS_MIN(xfs_bmap_worst_indlen(ip, temp),
2561                                          oldlen);
2562                 left.br_blockcount = temp;
2563                 left.br_startblock = nullstartblock(newlen);
2564
2565                 xfs_iext_prev(ifp, icur);
2566                 xfs_iext_update_extent(ip, state, icur, &left);
2567                 break;
2568
2569         case BMAP_RIGHT_CONTIG:
2570                 /*
2571                  * New allocation is contiguous with a delayed allocation
2572                  * on the right.
2573                  * Merge the new allocation with the right neighbor.
2574                  */
2575                 temp = new->br_blockcount + right.br_blockcount;
2576                 oldlen = startblockval(new->br_startblock) +
2577                         startblockval(right.br_startblock);
2578                 newlen = XFS_FILBLKS_MIN(xfs_bmap_worst_indlen(ip, temp),
2579                                          oldlen);
2580                 right.br_startoff = new->br_startoff;
2581                 right.br_startblock = nullstartblock(newlen);
2582                 right.br_blockcount = temp;
2583                 xfs_iext_update_extent(ip, state, icur, &right);
2584                 break;
2585
2586         case 0:
2587                 /*
2588                  * New allocation is not contiguous with another
2589                  * delayed allocation.
2590                  * Insert a new entry.
2591                  */
2592                 oldlen = newlen = 0;
2593                 xfs_iext_insert(ip, icur, new, state);
2594                 break;
2595         }
2596         if (oldlen != newlen) {
2597                 ASSERT(oldlen > newlen);
2598                 xfs_mod_fdblocks(ip->i_mount, (int64_t)(oldlen - newlen),
2599                                  false);
2600                 /*
2601                  * Nothing to do for disk quota accounting here.
2602                  */
2603                 xfs_mod_delalloc(ip->i_mount, (int64_t)newlen - oldlen);
2604         }
2605 }
2606
2607 /*
2608  * Convert a hole to a real allocation.
2609  */
2610 STATIC int                              /* error */
2611 xfs_bmap_add_extent_hole_real(
2612         struct xfs_trans        *tp,
2613         struct xfs_inode        *ip,
2614         int                     whichfork,
2615         struct xfs_iext_cursor  *icur,
2616         struct xfs_btree_cur    **curp,
2617         struct xfs_bmbt_irec    *new,
2618         int                     *logflagsp,
2619         int                     flags)
2620 {
2621         struct xfs_ifork        *ifp = XFS_IFORK_PTR(ip, whichfork);
2622         struct xfs_mount        *mp = ip->i_mount;
2623         struct xfs_btree_cur    *cur = *curp;
2624         int                     error;  /* error return value */
2625         int                     i;      /* temp state */
2626         xfs_bmbt_irec_t         left;   /* left neighbor extent entry */
2627         xfs_bmbt_irec_t         right;  /* right neighbor extent entry */
2628         int                     rval=0; /* return value (logging flags) */
2629         int                     state = xfs_bmap_fork_to_state(whichfork);
2630         struct xfs_bmbt_irec    old;
2631
2632         ASSERT(!isnullstartblock(new->br_startblock));
2633         ASSERT(!cur || !(cur->bc_ino.flags & XFS_BTCUR_BMBT_WASDEL));
2634
2635         XFS_STATS_INC(mp, xs_add_exlist);
2636
2637         /*
2638          * Check and set flags if this segment has a left neighbor.
2639          */
2640         if (xfs_iext_peek_prev_extent(ifp, icur, &left)) {
2641                 state |= BMAP_LEFT_VALID;
2642                 if (isnullstartblock(left.br_startblock))
2643                         state |= BMAP_LEFT_DELAY;
2644         }
2645
2646         /*
2647          * Check and set flags if this segment has a current value.
2648          * Not true if we're inserting into the "hole" at eof.
2649          */
2650         if (xfs_iext_get_extent(ifp, icur, &right)) {
2651                 state |= BMAP_RIGHT_VALID;
2652                 if (isnullstartblock(right.br_startblock))
2653                         state |= BMAP_RIGHT_DELAY;
2654         }
2655
2656         /*
2657          * We're inserting a real allocation between "left" and "right".
2658          * Set the contiguity flags.  Don't let extents get too large.
2659          */
2660         if ((state & BMAP_LEFT_VALID) && !(state & BMAP_LEFT_DELAY) &&
2661             left.br_startoff + left.br_blockcount == new->br_startoff &&
2662             left.br_startblock + left.br_blockcount == new->br_startblock &&
2663             left.br_state == new->br_state &&
2664             left.br_blockcount + new->br_blockcount <= MAXEXTLEN)
2665                 state |= BMAP_LEFT_CONTIG;
2666
2667         if ((state & BMAP_RIGHT_VALID) && !(state & BMAP_RIGHT_DELAY) &&
2668             new->br_startoff + new->br_blockcount == right.br_startoff &&
2669             new->br_startblock + new->br_blockcount == right.br_startblock &&
2670             new->br_state == right.br_state &&
2671             new->br_blockcount + right.br_blockcount <= MAXEXTLEN &&
2672             (!(state & BMAP_LEFT_CONTIG) ||
2673              left.br_blockcount + new->br_blockcount +
2674              right.br_blockcount <= MAXEXTLEN))
2675                 state |= BMAP_RIGHT_CONTIG;
2676
2677         error = 0;
2678         /*
2679          * Select which case we're in here, and implement it.
2680          */
2681         switch (state & (BMAP_LEFT_CONTIG | BMAP_RIGHT_CONTIG)) {
2682         case BMAP_LEFT_CONTIG | BMAP_RIGHT_CONTIG:
2683                 /*
2684                  * New allocation is contiguous with real allocations on the
2685                  * left and on the right.
2686                  * Merge all three into a single extent record.
2687                  */
2688                 left.br_blockcount += new->br_blockcount + right.br_blockcount;
2689
2690                 xfs_iext_remove(ip, icur, state);
2691                 xfs_iext_prev(ifp, icur);
2692                 xfs_iext_update_extent(ip, state, icur, &left);
2693                 ifp->if_nextents--;
2694
2695                 if (cur == NULL) {
2696                         rval = XFS_ILOG_CORE | xfs_ilog_fext(whichfork);
2697                 } else {
2698                         rval = XFS_ILOG_CORE;
2699                         error = xfs_bmbt_lookup_eq(cur, &right, &i);
2700                         if (error)
2701                                 goto done;
2702                         if (XFS_IS_CORRUPT(mp, i != 1)) {
2703                                 error = -EFSCORRUPTED;
2704                                 goto done;
2705                         }
2706                         error = xfs_btree_delete(cur, &i);
2707                         if (error)
2708                                 goto done;
2709                         if (XFS_IS_CORRUPT(mp, i != 1)) {
2710                                 error = -EFSCORRUPTED;
2711                                 goto done;
2712                         }
2713                         error = xfs_btree_decrement(cur, 0, &i);
2714                         if (error)
2715                                 goto done;
2716                         if (XFS_IS_CORRUPT(mp, i != 1)) {
2717                                 error = -EFSCORRUPTED;
2718                                 goto done;
2719                         }
2720                         error = xfs_bmbt_update(cur, &left);
2721                         if (error)
2722                                 goto done;
2723                 }
2724                 break;
2725
2726         case BMAP_LEFT_CONTIG:
2727                 /*
2728                  * New allocation is contiguous with a real allocation
2729                  * on the left.
2730                  * Merge the new allocation with the left neighbor.
2731                  */
2732                 old = left;
2733                 left.br_blockcount += new->br_blockcount;
2734
2735                 xfs_iext_prev(ifp, icur);
2736                 xfs_iext_update_extent(ip, state, icur, &left);
2737
2738                 if (cur == NULL) {
2739                         rval = xfs_ilog_fext(whichfork);
2740                 } else {
2741                         rval = 0;
2742                         error = xfs_bmbt_lookup_eq(cur, &old, &i);
2743                         if (error)
2744                                 goto done;
2745                         if (XFS_IS_CORRUPT(mp, i != 1)) {
2746                                 error = -EFSCORRUPTED;
2747                                 goto done;
2748                         }
2749                         error = xfs_bmbt_update(cur, &left);
2750                         if (error)
2751                                 goto done;
2752                 }
2753                 break;
2754
2755         case BMAP_RIGHT_CONTIG:
2756                 /*
2757                  * New allocation is contiguous with a real allocation
2758                  * on the right.
2759                  * Merge the new allocation with the right neighbor.
2760                  */
2761                 old = right;
2762
2763                 right.br_startoff = new->br_startoff;
2764                 right.br_startblock = new->br_startblock;
2765                 right.br_blockcount += new->br_blockcount;
2766                 xfs_iext_update_extent(ip, state, icur, &right);
2767
2768                 if (cur == NULL) {
2769                         rval = xfs_ilog_fext(whichfork);
2770                 } else {
2771                         rval = 0;
2772                         error = xfs_bmbt_lookup_eq(cur, &old, &i);
2773                         if (error)
2774                                 goto done;
2775                         if (XFS_IS_CORRUPT(mp, i != 1)) {
2776                                 error = -EFSCORRUPTED;
2777                                 goto done;
2778                         }
2779                         error = xfs_bmbt_update(cur, &right);
2780                         if (error)
2781                                 goto done;
2782                 }
2783                 break;
2784
2785         case 0:
2786                 /*
2787                  * New allocation is not contiguous with another
2788                  * real allocation.
2789                  * Insert a new entry.
2790                  */
2791                 xfs_iext_insert(ip, icur, new, state);
2792                 ifp->if_nextents++;
2793
2794                 if (cur == NULL) {
2795                         rval = XFS_ILOG_CORE | xfs_ilog_fext(whichfork);
2796                 } else {
2797                         rval = XFS_ILOG_CORE;
2798                         error = xfs_bmbt_lookup_eq(cur, new, &i);
2799                         if (error)
2800                                 goto done;
2801                         if (XFS_IS_CORRUPT(mp, i != 0)) {
2802                                 error = -EFSCORRUPTED;
2803                                 goto done;
2804                         }
2805                         error = xfs_btree_insert(cur, &i);
2806                         if (error)
2807                                 goto done;
2808                         if (XFS_IS_CORRUPT(mp, i != 1)) {
2809                                 error = -EFSCORRUPTED;
2810                                 goto done;
2811                         }
2812                 }
2813                 break;
2814         }
2815
2816         /* add reverse mapping unless caller opted out */
2817         if (!(flags & XFS_BMAPI_NORMAP))
2818                 xfs_rmap_map_extent(tp, ip, whichfork, new);
2819
2820         /* convert to a btree if necessary */
2821         if (xfs_bmap_needs_btree(ip, whichfork)) {
2822                 int     tmp_logflags;   /* partial log flag return val */
2823
2824                 ASSERT(cur == NULL);
2825                 error = xfs_bmap_extents_to_btree(tp, ip, curp, 0,
2826                                 &tmp_logflags, whichfork);
2827                 *logflagsp |= tmp_logflags;
2828                 cur = *curp;
2829                 if (error)
2830                         goto done;
2831         }
2832
2833         /* clear out the allocated field, done with it now in any case. */
2834         if (cur)
2835                 cur->bc_ino.allocated = 0;
2836
2837         xfs_bmap_check_leaf_extents(cur, ip, whichfork);
2838 done:
2839         *logflagsp |= rval;
2840         return error;
2841 }
2842
2843 /*
2844  * Functions used in the extent read, allocate and remove paths
2845  */
2846
2847 /*
2848  * Adjust the size of the new extent based on i_extsize and rt extsize.
2849  */
2850 int
2851 xfs_bmap_extsize_align(
2852         xfs_mount_t     *mp,
2853         xfs_bmbt_irec_t *gotp,          /* next extent pointer */
2854         xfs_bmbt_irec_t *prevp,         /* previous extent pointer */
2855         xfs_extlen_t    extsz,          /* align to this extent size */
2856         int             rt,             /* is this a realtime inode? */
2857         int             eof,            /* is extent at end-of-file? */
2858         int             delay,          /* creating delalloc extent? */
2859         int             convert,        /* overwriting unwritten extent? */
2860         xfs_fileoff_t   *offp,          /* in/out: aligned offset */
2861         xfs_extlen_t    *lenp)          /* in/out: aligned length */
2862 {
2863         xfs_fileoff_t   orig_off;       /* original offset */
2864         xfs_extlen_t    orig_alen;      /* original length */
2865         xfs_fileoff_t   orig_end;       /* original off+len */
2866         xfs_fileoff_t   nexto;          /* next file offset */
2867         xfs_fileoff_t   prevo;          /* previous file offset */
2868         xfs_fileoff_t   align_off;      /* temp for offset */
2869         xfs_extlen_t    align_alen;     /* temp for length */
2870         xfs_extlen_t    temp;           /* temp for calculations */
2871
2872         if (convert)
2873                 return 0;
2874
2875         orig_off = align_off = *offp;
2876         orig_alen = align_alen = *lenp;
2877         orig_end = orig_off + orig_alen;
2878
2879         /*
2880          * If this request overlaps an existing extent, then don't
2881          * attempt to perform any additional alignment.
2882          */
2883         if (!delay && !eof &&
2884             (orig_off >= gotp->br_startoff) &&
2885             (orig_end <= gotp->br_startoff + gotp->br_blockcount)) {
2886                 return 0;
2887         }
2888
2889         /*
2890          * If the file offset is unaligned vs. the extent size
2891          * we need to align it.  This will be possible unless
2892          * the file was previously written with a kernel that didn't
2893          * perform this alignment, or if a truncate shot us in the
2894          * foot.
2895          */
2896         div_u64_rem(orig_off, extsz, &temp);
2897         if (temp) {
2898                 align_alen += temp;
2899                 align_off -= temp;
2900         }
2901
2902         /* Same adjustment for the end of the requested area. */
2903         temp = (align_alen % extsz);
2904         if (temp)
2905                 align_alen += extsz - temp;
2906
2907         /*
2908          * For large extent hint sizes, the aligned extent might be larger than
2909          * MAXEXTLEN. In that case, reduce the size by an extsz so that it pulls
2910          * the length back under MAXEXTLEN. The outer allocation loops handle
2911          * short allocation just fine, so it is safe to do this. We only want to
2912          * do it when we are forced to, though, because it means more allocation
2913          * operations are required.
2914          */
2915         while (align_alen > MAXEXTLEN)
2916                 align_alen -= extsz;
2917         ASSERT(align_alen <= MAXEXTLEN);
2918
2919         /*
2920          * If the previous block overlaps with this proposed allocation
2921          * then move the start forward without adjusting the length.
2922          */
2923         if (prevp->br_startoff != NULLFILEOFF) {
2924                 if (prevp->br_startblock == HOLESTARTBLOCK)
2925                         prevo = prevp->br_startoff;
2926                 else
2927                         prevo = prevp->br_startoff + prevp->br_blockcount;
2928         } else
2929                 prevo = 0;
2930         if (align_off != orig_off && align_off < prevo)
2931                 align_off = prevo;
2932         /*
2933          * If the next block overlaps with this proposed allocation
2934          * then move the start back without adjusting the length,
2935          * but not before offset 0.
2936          * This may of course make the start overlap previous block,
2937          * and if we hit the offset 0 limit then the next block
2938          * can still overlap too.
2939          */
2940         if (!eof && gotp->br_startoff != NULLFILEOFF) {
2941                 if ((delay && gotp->br_startblock == HOLESTARTBLOCK) ||
2942                     (!delay && gotp->br_startblock == DELAYSTARTBLOCK))
2943                         nexto = gotp->br_startoff + gotp->br_blockcount;
2944                 else
2945                         nexto = gotp->br_startoff;
2946         } else
2947                 nexto = NULLFILEOFF;
2948         if (!eof &&
2949             align_off + align_alen != orig_end &&
2950             align_off + align_alen > nexto)
2951                 align_off = nexto > align_alen ? nexto - align_alen : 0;
2952         /*
2953          * If we're now overlapping the next or previous extent that
2954          * means we can't fit an extsz piece in this hole.  Just move
2955          * the start forward to the first valid spot and set
2956          * the length so we hit the end.
2957          */
2958         if (align_off != orig_off && align_off < prevo)
2959                 align_off = prevo;
2960         if (align_off + align_alen != orig_end &&
2961             align_off + align_alen > nexto &&
2962             nexto != NULLFILEOFF) {
2963                 ASSERT(nexto > prevo);
2964                 align_alen = nexto - align_off;
2965         }
2966
2967         /*
2968          * If realtime, and the result isn't a multiple of the realtime
2969          * extent size we need to remove blocks until it is.
2970          */
2971         if (rt && (temp = (align_alen % mp->m_sb.sb_rextsize))) {
2972                 /*
2973                  * We're not covering the original request, or
2974                  * we won't be able to once we fix the length.
2975                  */
2976                 if (orig_off < align_off ||
2977                     orig_end > align_off + align_alen ||
2978                     align_alen - temp < orig_alen)
2979                         return -EINVAL;
2980                 /*
2981                  * Try to fix it by moving the start up.
2982                  */
2983                 if (align_off + temp <= orig_off) {
2984                         align_alen -= temp;
2985                         align_off += temp;
2986                 }
2987                 /*
2988                  * Try to fix it by moving the end in.
2989                  */
2990                 else if (align_off + align_alen - temp >= orig_end)
2991                         align_alen -= temp;
2992                 /*
2993                  * Set the start to the minimum then trim the length.
2994                  */
2995                 else {
2996                         align_alen -= orig_off - align_off;
2997                         align_off = orig_off;
2998                         align_alen -= align_alen % mp->m_sb.sb_rextsize;
2999                 }
3000                 /*
3001                  * Result doesn't cover the request, fail it.
3002                  */
3003                 if (orig_off < align_off || orig_end > align_off + align_alen)
3004                         return -EINVAL;
3005         } else {
3006                 ASSERT(orig_off >= align_off);
3007                 /* see MAXEXTLEN handling above */
3008                 ASSERT(orig_end <= align_off + align_alen ||
3009                        align_alen + extsz > MAXEXTLEN);
3010         }
3011
3012 #ifdef DEBUG
3013         if (!eof && gotp->br_startoff != NULLFILEOFF)
3014                 ASSERT(align_off + align_alen <= gotp->br_startoff);
3015         if (prevp->br_startoff != NULLFILEOFF)
3016                 ASSERT(align_off >= prevp->br_startoff + prevp->br_blockcount);
3017 #endif
3018
3019         *lenp = align_alen;
3020         *offp = align_off;
3021         return 0;
3022 }
3023
3024 #define XFS_ALLOC_GAP_UNITS     4
3025
3026 void
3027 xfs_bmap_adjacent(
3028         struct xfs_bmalloca     *ap)    /* bmap alloc argument struct */
3029 {
3030         xfs_fsblock_t   adjust;         /* adjustment to block numbers */
3031         xfs_agnumber_t  fb_agno;        /* ag number of ap->firstblock */
3032         xfs_mount_t     *mp;            /* mount point structure */
3033         int             nullfb;         /* true if ap->firstblock isn't set */
3034         int             rt;             /* true if inode is realtime */
3035
3036 #define ISVALID(x,y)    \
3037         (rt ? \
3038                 (x) < mp->m_sb.sb_rblocks : \
3039                 XFS_FSB_TO_AGNO(mp, x) == XFS_FSB_TO_AGNO(mp, y) && \
3040                 XFS_FSB_TO_AGNO(mp, x) < mp->m_sb.sb_agcount && \
3041                 XFS_FSB_TO_AGBNO(mp, x) < mp->m_sb.sb_agblocks)
3042
3043         mp = ap->ip->i_mount;
3044         nullfb = ap->tp->t_firstblock == NULLFSBLOCK;
3045         rt = XFS_IS_REALTIME_INODE(ap->ip) &&
3046                 (ap->datatype & XFS_ALLOC_USERDATA);
3047         fb_agno = nullfb ? NULLAGNUMBER : XFS_FSB_TO_AGNO(mp,
3048                                                         ap->tp->t_firstblock);
3049         /*
3050          * If allocating at eof, and there's a previous real block,
3051          * try to use its last block as our starting point.
3052          */
3053         if (ap->eof && ap->prev.br_startoff != NULLFILEOFF &&
3054             !isnullstartblock(ap->prev.br_startblock) &&
3055             ISVALID(ap->prev.br_startblock + ap->prev.br_blockcount,
3056                     ap->prev.br_startblock)) {
3057                 ap->blkno = ap->prev.br_startblock + ap->prev.br_blockcount;
3058                 /*
3059                  * Adjust for the gap between prevp and us.
3060                  */
3061                 adjust = ap->offset -
3062                         (ap->prev.br_startoff + ap->prev.br_blockcount);
3063                 if (adjust &&
3064                     ISVALID(ap->blkno + adjust, ap->prev.br_startblock))
3065                         ap->blkno += adjust;
3066         }
3067         /*
3068          * If not at eof, then compare the two neighbor blocks.
3069          * Figure out whether either one gives us a good starting point,
3070          * and pick the better one.
3071          */
3072         else if (!ap->eof) {
3073                 xfs_fsblock_t   gotbno;         /* right side block number */
3074                 xfs_fsblock_t   gotdiff=0;      /* right side difference */
3075                 xfs_fsblock_t   prevbno;        /* left side block number */
3076                 xfs_fsblock_t   prevdiff=0;     /* left side difference */
3077
3078                 /*
3079                  * If there's a previous (left) block, select a requested
3080                  * start block based on it.
3081                  */
3082                 if (ap->prev.br_startoff != NULLFILEOFF &&
3083                     !isnullstartblock(ap->prev.br_startblock) &&
3084                     (prevbno = ap->prev.br_startblock +
3085                                ap->prev.br_blockcount) &&
3086                     ISVALID(prevbno, ap->prev.br_startblock)) {
3087                         /*
3088                          * Calculate gap to end of previous block.
3089                          */
3090                         adjust = prevdiff = ap->offset -
3091                                 (ap->prev.br_startoff +
3092                                  ap->prev.br_blockcount);
3093                         /*
3094                          * Figure the startblock based on the previous block's
3095                          * end and the gap size.
3096                          * Heuristic!
3097                          * If the gap is large relative to the piece we're
3098                          * allocating, or using it gives us an invalid block
3099                          * number, then just use the end of the previous block.
3100                          */
3101                         if (prevdiff <= XFS_ALLOC_GAP_UNITS * ap->length &&
3102                             ISVALID(prevbno + prevdiff,
3103                                     ap->prev.br_startblock))
3104                                 prevbno += adjust;
3105                         else
3106                                 prevdiff += adjust;
3107                         /*
3108                          * If the firstblock forbids it, can't use it,
3109                          * must use default.
3110                          */
3111                         if (!rt && !nullfb &&
3112                             XFS_FSB_TO_AGNO(mp, prevbno) != fb_agno)
3113                                 prevbno = NULLFSBLOCK;
3114                 }
3115                 /*
3116                  * No previous block or can't follow it, just default.
3117                  */
3118                 else
3119                         prevbno = NULLFSBLOCK;
3120                 /*
3121                  * If there's a following (right) block, select a requested
3122                  * start block based on it.
3123                  */
3124                 if (!isnullstartblock(ap->got.br_startblock)) {
3125                         /*
3126                          * Calculate gap to start of next block.
3127                          */
3128                         adjust = gotdiff = ap->got.br_startoff - ap->offset;
3129                         /*
3130                          * Figure the startblock based on the next block's
3131                          * start and the gap size.
3132                          */
3133                         gotbno = ap->got.br_startblock;
3134                         /*
3135                          * Heuristic!
3136                          * If the gap is large relative to the piece we're
3137                          * allocating, or using it gives us an invalid block
3138                          * number, then just use the start of the next block
3139                          * offset by our length.
3140                          */
3141                         if (gotdiff <= XFS_ALLOC_GAP_UNITS * ap->length &&
3142                             ISVALID(gotbno - gotdiff, gotbno))
3143                                 gotbno -= adjust;
3144                         else if (ISVALID(gotbno - ap->length, gotbno)) {
3145                                 gotbno -= ap->length;
3146                                 gotdiff += adjust - ap->length;
3147                         } else
3148                                 gotdiff += adjust;
3149                         /*
3150                          * If the firstblock forbids it, can't use it,
3151                          * must use default.
3152                          */
3153                         if (!rt && !nullfb &&
3154                             XFS_FSB_TO_AGNO(mp, gotbno) != fb_agno)
3155                                 gotbno = NULLFSBLOCK;
3156                 }
3157                 /*
3158                  * No next block, just default.
3159                  */
3160                 else
3161                         gotbno = NULLFSBLOCK;
3162                 /*
3163                  * If both valid, pick the better one, else the only good
3164                  * one, else ap->blkno is already set (to 0 or the inode block).
3165                  */
3166                 if (prevbno != NULLFSBLOCK && gotbno != NULLFSBLOCK)
3167                         ap->blkno = prevdiff <= gotdiff ? prevbno : gotbno;
3168                 else if (prevbno != NULLFSBLOCK)
3169                         ap->blkno = prevbno;
3170                 else if (gotbno != NULLFSBLOCK)
3171                         ap->blkno = gotbno;
3172         }
3173 #undef ISVALID
3174 }
3175
3176 static int
3177 xfs_bmap_longest_free_extent(
3178         struct xfs_trans        *tp,
3179         xfs_agnumber_t          ag,
3180         xfs_extlen_t            *blen,
3181         int                     *notinit)
3182 {
3183         struct xfs_mount        *mp = tp->t_mountp;
3184         struct xfs_perag        *pag;
3185         xfs_extlen_t            longest;
3186         int                     error = 0;
3187
3188         pag = xfs_perag_get(mp, ag);
3189         if (!pag->pagf_init) {
3190                 error = xfs_alloc_pagf_init(mp, tp, ag, XFS_ALLOC_FLAG_TRYLOCK);
3191                 if (error) {
3192                         /* Couldn't lock the AGF, so skip this AG. */
3193                         if (error == -EAGAIN) {
3194                                 *notinit = 1;
3195                                 error = 0;
3196                         }
3197                         goto out;
3198                 }
3199         }
3200
3201         longest = xfs_alloc_longest_free_extent(pag,
3202                                 xfs_alloc_min_freelist(mp, pag),
3203                                 xfs_ag_resv_needed(pag, XFS_AG_RESV_NONE));
3204         if (*blen < longest)
3205                 *blen = longest;
3206
3207 out:
3208         xfs_perag_put(pag);
3209         return error;
3210 }
3211
3212 static void
3213 xfs_bmap_select_minlen(
3214         struct xfs_bmalloca     *ap,
3215         struct xfs_alloc_arg    *args,
3216         xfs_extlen_t            *blen,
3217         int                     notinit)
3218 {
3219         if (notinit || *blen < ap->minlen) {
3220                 /*
3221                  * Since we did a BUF_TRYLOCK above, it is possible that
3222                  * there is space for this request.
3223                  */
3224                 args->minlen = ap->minlen;
3225         } else if (*blen < args->maxlen) {
3226                 /*
3227                  * If the best seen length is less than the request length,
3228                  * use the best as the minimum.
3229                  */
3230                 args->minlen = *blen;
3231         } else {
3232                 /*
3233                  * Otherwise we've seen an extent as big as maxlen, use that
3234                  * as the minimum.
3235                  */
3236                 args->minlen = args->maxlen;
3237         }
3238 }
3239
3240 STATIC int
3241 xfs_bmap_btalloc_nullfb(
3242         struct xfs_bmalloca     *ap,
3243         struct xfs_alloc_arg    *args,
3244         xfs_extlen_t            *blen)
3245 {
3246         struct xfs_mount        *mp = ap->ip->i_mount;
3247         xfs_agnumber_t          ag, startag;
3248         int                     notinit = 0;
3249         int                     error;
3250
3251         args->type = XFS_ALLOCTYPE_START_BNO;
3252         args->total = ap->total;
3253
3254         startag = ag = XFS_FSB_TO_AGNO(mp, args->fsbno);
3255         if (startag == NULLAGNUMBER)
3256                 startag = ag = 0;
3257
3258         while (*blen < args->maxlen) {
3259                 error = xfs_bmap_longest_free_extent(args->tp, ag, blen,
3260                                                      &notinit);
3261                 if (error)
3262                         return error;
3263
3264                 if (++ag == mp->m_sb.sb_agcount)
3265                         ag = 0;
3266                 if (ag == startag)
3267                         break;
3268         }
3269
3270         xfs_bmap_select_minlen(ap, args, blen, notinit);
3271         return 0;
3272 }
3273
3274 STATIC int
3275 xfs_bmap_btalloc_filestreams(
3276         struct xfs_bmalloca     *ap,
3277         struct xfs_alloc_arg    *args,
3278         xfs_extlen_t            *blen)
3279 {
3280         struct xfs_mount        *mp = ap->ip->i_mount;
3281         xfs_agnumber_t          ag;
3282         int                     notinit = 0;
3283         int                     error;
3284
3285         args->type = XFS_ALLOCTYPE_NEAR_BNO;
3286         args->total = ap->total;
3287
3288         ag = XFS_FSB_TO_AGNO(mp, args->fsbno);
3289         if (ag == NULLAGNUMBER)
3290                 ag = 0;
3291
3292         error = xfs_bmap_longest_free_extent(args->tp, ag, blen, &notinit);
3293         if (error)
3294                 return error;
3295
3296         if (*blen < args->maxlen) {
3297                 error = xfs_filestream_new_ag(ap, &ag);
3298                 if (error)
3299                         return error;
3300
3301                 error = xfs_bmap_longest_free_extent(args->tp, ag, blen,
3302                                                      &notinit);
3303                 if (error)
3304                         return error;
3305
3306         }
3307
3308         xfs_bmap_select_minlen(ap, args, blen, notinit);
3309
3310         /*
3311          * Set the failure fallback case to look in the selected AG as stream
3312          * may have moved.
3313          */
3314         ap->blkno = args->fsbno = XFS_AGB_TO_FSB(mp, ag, 0);
3315         return 0;
3316 }
3317
3318 /* Update all inode and quota accounting for the allocation we just did. */
3319 static void
3320 xfs_bmap_btalloc_accounting(
3321         struct xfs_bmalloca     *ap,
3322         struct xfs_alloc_arg    *args)
3323 {
3324         if (ap->flags & XFS_BMAPI_COWFORK) {
3325                 /*
3326                  * COW fork blocks are in-core only and thus are treated as
3327                  * in-core quota reservation (like delalloc blocks) even when
3328                  * converted to real blocks. The quota reservation is not
3329                  * accounted to disk until blocks are remapped to the data
3330                  * fork. So if these blocks were previously delalloc, we
3331                  * already have quota reservation and there's nothing to do
3332                  * yet.
3333                  */
3334                 if (ap->wasdel) {
3335                         xfs_mod_delalloc(ap->ip->i_mount, -(int64_t)args->len);
3336                         return;
3337                 }
3338
3339                 /*
3340                  * Otherwise, we've allocated blocks in a hole. The transaction
3341                  * has acquired in-core quota reservation for this extent.
3342                  * Rather than account these as real blocks, however, we reduce
3343                  * the transaction quota reservation based on the allocation.
3344                  * This essentially transfers the transaction quota reservation
3345                  * to that of a delalloc extent.
3346                  */
3347                 ap->ip->i_delayed_blks += args->len;
3348                 xfs_trans_mod_dquot_byino(ap->tp, ap->ip, XFS_TRANS_DQ_RES_BLKS,
3349                                 -(long)args->len);
3350                 return;
3351         }
3352
3353         /* data/attr fork only */
3354         ap->ip->i_nblocks += args->len;
3355         xfs_trans_log_inode(ap->tp, ap->ip, XFS_ILOG_CORE);
3356         if (ap->wasdel) {
3357                 ap->ip->i_delayed_blks -= args->len;
3358                 xfs_mod_delalloc(ap->ip->i_mount, -(int64_t)args->len);
3359         }
3360         xfs_trans_mod_dquot_byino(ap->tp, ap->ip,
3361                 ap->wasdel ? XFS_TRANS_DQ_DELBCOUNT : XFS_TRANS_DQ_BCOUNT,
3362                 args->len);
3363 }
3364
3365 static int
3366 xfs_bmap_compute_alignments(
3367         struct xfs_bmalloca     *ap,
3368         struct xfs_alloc_arg    *args)
3369 {
3370         struct xfs_mount        *mp = args->mp;
3371         xfs_extlen_t            align = 0; /* minimum allocation alignment */
3372         int                     stripe_align = 0;
3373
3374         /* stripe alignment for allocation is determined by mount parameters */
3375         if (mp->m_swidth && xfs_has_swalloc(mp))
3376                 stripe_align = mp->m_swidth;
3377         else if (mp->m_dalign)
3378                 stripe_align = mp->m_dalign;
3379
3380         if (ap->flags & XFS_BMAPI_COWFORK)
3381                 align = xfs_get_cowextsz_hint(ap->ip);
3382         else if (ap->datatype & XFS_ALLOC_USERDATA)
3383                 align = xfs_get_extsz_hint(ap->ip);
3384         if (align) {
3385                 if (xfs_bmap_extsize_align(mp, &ap->got, &ap->prev, align, 0,
3386                                         ap->eof, 0, ap->conv, &ap->offset,
3387                                         &ap->length))
3388                         ASSERT(0);
3389                 ASSERT(ap->length);
3390         }
3391
3392         /* apply extent size hints if obtained earlier */
3393         if (align) {
3394                 args->prod = align;
3395                 div_u64_rem(ap->offset, args->prod, &args->mod);
3396                 if (args->mod)
3397                         args->mod = args->prod - args->mod;
3398         } else if (mp->m_sb.sb_blocksize >= PAGE_SIZE) {
3399                 args->prod = 1;
3400                 args->mod = 0;
3401         } else {
3402                 args->prod = PAGE_SIZE >> mp->m_sb.sb_blocklog;
3403                 div_u64_rem(ap->offset, args->prod, &args->mod);
3404                 if (args->mod)
3405                         args->mod = args->prod - args->mod;
3406         }
3407
3408         return stripe_align;
3409 }
3410
3411 static void
3412 xfs_bmap_process_allocated_extent(
3413         struct xfs_bmalloca     *ap,
3414         struct xfs_alloc_arg    *args,
3415         xfs_fileoff_t           orig_offset,
3416         xfs_extlen_t            orig_length)
3417 {
3418         int                     nullfb;
3419
3420         nullfb = ap->tp->t_firstblock == NULLFSBLOCK;
3421
3422         /*
3423          * check the allocation happened at the same or higher AG than
3424          * the first block that was allocated.
3425          */
3426         ASSERT(nullfb ||
3427                 XFS_FSB_TO_AGNO(args->mp, ap->tp->t_firstblock) <=
3428                 XFS_FSB_TO_AGNO(args->mp, args->fsbno));
3429
3430         ap->blkno = args->fsbno;
3431         if (nullfb)
3432                 ap->tp->t_firstblock = args->fsbno;
3433         ap->length = args->len;
3434         /*
3435          * If the extent size hint is active, we tried to round the
3436          * caller's allocation request offset down to extsz and the
3437          * length up to another extsz boundary.  If we found a free
3438          * extent we mapped it in starting at this new offset.  If the
3439          * newly mapped space isn't long enough to cover any of the
3440          * range of offsets that was originally requested, move the
3441          * mapping up so that we can fill as much of the caller's
3442          * original request as possible.  Free space is apparently
3443          * very fragmented so we're unlikely to be able to satisfy the
3444          * hints anyway.
3445          */
3446         if (ap->length <= orig_length)
3447                 ap->offset = orig_offset;
3448         else if (ap->offset + ap->length < orig_offset + orig_length)
3449                 ap->offset = orig_offset + orig_length - ap->length;
3450         xfs_bmap_btalloc_accounting(ap, args);
3451 }
3452
3453 #ifdef DEBUG
3454 static int
3455 xfs_bmap_exact_minlen_extent_alloc(
3456         struct xfs_bmalloca     *ap)
3457 {
3458         struct xfs_mount        *mp = ap->ip->i_mount;
3459         struct xfs_alloc_arg    args = { .tp = ap->tp, .mp = mp };
3460         xfs_fileoff_t           orig_offset;
3461         xfs_extlen_t            orig_length;
3462         int                     error;
3463
3464         ASSERT(ap->length);
3465
3466         if (ap->minlen != 1) {
3467                 ap->blkno = NULLFSBLOCK;
3468                 ap->length = 0;
3469                 return 0;
3470         }
3471
3472         orig_offset = ap->offset;
3473         orig_length = ap->length;
3474
3475         args.alloc_minlen_only = 1;
3476
3477         xfs_bmap_compute_alignments(ap, &args);
3478
3479         if (ap->tp->t_firstblock == NULLFSBLOCK) {
3480                 /*
3481                  * Unlike the longest extent available in an AG, we don't track
3482                  * the length of an AG's shortest extent.
3483                  * XFS_ERRTAG_BMAP_ALLOC_MINLEN_EXTENT is a debug only knob and
3484                  * hence we can afford to start traversing from the 0th AG since
3485                  * we need not be concerned about a drop in performance in
3486                  * "debug only" code paths.
3487                  */
3488                 ap->blkno = XFS_AGB_TO_FSB(mp, 0, 0);
3489         } else {
3490                 ap->blkno = ap->tp->t_firstblock;
3491         }
3492
3493         args.fsbno = ap->blkno;
3494         args.oinfo = XFS_RMAP_OINFO_SKIP_UPDATE;
3495         args.type = XFS_ALLOCTYPE_FIRST_AG;
3496         args.minlen = args.maxlen = ap->minlen;
3497         args.total = ap->total;
3498
3499         args.alignment = 1;
3500         args.minalignslop = 0;
3501
3502         args.minleft = ap->minleft;
3503         args.wasdel = ap->wasdel;
3504         args.resv = XFS_AG_RESV_NONE;
3505         args.datatype = ap->datatype;
3506
3507         error = xfs_alloc_vextent(&args);
3508         if (error)
3509                 return error;
3510
3511         if (args.fsbno != NULLFSBLOCK) {
3512                 xfs_bmap_process_allocated_extent(ap, &args, orig_offset,
3513                         orig_length);
3514         } else {
3515                 ap->blkno = NULLFSBLOCK;
3516                 ap->length = 0;
3517         }
3518
3519         return 0;
3520 }
3521 #else
3522
3523 #define xfs_bmap_exact_minlen_extent_alloc(bma) (-EFSCORRUPTED)
3524
3525 #endif
3526
3527 STATIC int
3528 xfs_bmap_btalloc(
3529         struct xfs_bmalloca     *ap)
3530 {
3531         struct xfs_mount        *mp = ap->ip->i_mount;
3532         struct xfs_alloc_arg    args = { .tp = ap->tp, .mp = mp };
3533         xfs_alloctype_t         atype = 0;
3534         xfs_agnumber_t          fb_agno;        /* ag number of ap->firstblock */
3535         xfs_agnumber_t          ag;
3536         xfs_fileoff_t           orig_offset;
3537         xfs_extlen_t            orig_length;
3538         xfs_extlen_t            blen;
3539         xfs_extlen_t            nextminlen = 0;
3540         int                     nullfb; /* true if ap->firstblock isn't set */
3541         int                     isaligned;
3542         int                     tryagain;
3543         int                     error;
3544         int                     stripe_align;
3545
3546         ASSERT(ap->length);
3547         orig_offset = ap->offset;
3548         orig_length = ap->length;
3549
3550         stripe_align = xfs_bmap_compute_alignments(ap, &args);
3551
3552         nullfb = ap->tp->t_firstblock == NULLFSBLOCK;
3553         fb_agno = nullfb ? NULLAGNUMBER : XFS_FSB_TO_AGNO(mp,
3554                                                         ap->tp->t_firstblock);
3555         if (nullfb) {
3556                 if ((ap->datatype & XFS_ALLOC_USERDATA) &&
3557                     xfs_inode_is_filestream(ap->ip)) {
3558                         ag = xfs_filestream_lookup_ag(ap->ip);
3559                         ag = (ag != NULLAGNUMBER) ? ag : 0;
3560                         ap->blkno = XFS_AGB_TO_FSB(mp, ag, 0);
3561                 } else {
3562                         ap->blkno = XFS_INO_TO_FSB(mp, ap->ip->i_ino);
3563                 }
3564         } else
3565                 ap->blkno = ap->tp->t_firstblock;
3566
3567         xfs_bmap_adjacent(ap);
3568
3569         /*
3570          * If allowed, use ap->blkno; otherwise must use firstblock since
3571          * it's in the right allocation group.
3572          */
3573         if (nullfb || XFS_FSB_TO_AGNO(mp, ap->blkno) == fb_agno)
3574                 ;
3575         else
3576                 ap->blkno = ap->tp->t_firstblock;
3577         /*
3578          * Normal allocation, done through xfs_alloc_vextent.
3579          */
3580         tryagain = isaligned = 0;
3581         args.fsbno = ap->blkno;
3582         args.oinfo = XFS_RMAP_OINFO_SKIP_UPDATE;
3583
3584         /* Trim the allocation back to the maximum an AG can fit. */
3585         args.maxlen = min(ap->length, mp->m_ag_max_usable);
3586         blen = 0;
3587         if (nullfb) {
3588                 /*
3589                  * Search for an allocation group with a single extent large
3590                  * enough for the request.  If one isn't found, then adjust
3591                  * the minimum allocation size to the largest space found.
3592                  */
3593                 if ((ap->datatype & XFS_ALLOC_USERDATA) &&
3594                     xfs_inode_is_filestream(ap->ip))
3595                         error = xfs_bmap_btalloc_filestreams(ap, &args, &blen);
3596                 else
3597                         error = xfs_bmap_btalloc_nullfb(ap, &args, &blen);
3598                 if (error)
3599                         return error;
3600         } else if (ap->tp->t_flags & XFS_TRANS_LOWMODE) {
3601                 if (xfs_inode_is_filestream(ap->ip))
3602                         args.type = XFS_ALLOCTYPE_FIRST_AG;
3603                 else
3604                         args.type = XFS_ALLOCTYPE_START_BNO;
3605                 args.total = args.minlen = ap->minlen;
3606         } else {
3607                 args.type = XFS_ALLOCTYPE_NEAR_BNO;
3608                 args.total = ap->total;
3609                 args.minlen = ap->minlen;
3610         }
3611
3612         /*
3613          * If we are not low on available data blocks, and the underlying
3614          * logical volume manager is a stripe, and the file offset is zero then
3615          * try to allocate data blocks on stripe unit boundary. NOTE: ap->aeof
3616          * is only set if the allocation length is >= the stripe unit and the
3617          * allocation offset is at the end of file.
3618          */
3619         if (!(ap->tp->t_flags & XFS_TRANS_LOWMODE) && ap->aeof) {
3620                 if (!ap->offset) {
3621                         args.alignment = stripe_align;
3622                         atype = args.type;
3623                         isaligned = 1;
3624                         /*
3625                          * Adjust minlen to try and preserve alignment if we
3626                          * can't guarantee an aligned maxlen extent.
3627                          */
3628                         if (blen > args.alignment &&
3629                             blen <= args.maxlen + args.alignment)
3630                                 args.minlen = blen - args.alignment;
3631                         args.minalignslop = 0;
3632                 } else {
3633                         /*
3634                          * First try an exact bno allocation.
3635                          * If it fails then do a near or start bno
3636                          * allocation with alignment turned on.
3637                          */
3638                         atype = args.type;
3639                         tryagain = 1;
3640                         args.type = XFS_ALLOCTYPE_THIS_BNO;
3641                         args.alignment = 1;
3642                         /*
3643                          * Compute the minlen+alignment for the
3644                          * next case.  Set slop so that the value
3645                          * of minlen+alignment+slop doesn't go up
3646                          * between the calls.
3647                          */
3648                         if (blen > stripe_align && blen <= args.maxlen)
3649                                 nextminlen = blen - stripe_align;
3650                         else
3651                                 nextminlen = args.minlen;
3652                         if (nextminlen + stripe_align > args.minlen + 1)
3653                                 args.minalignslop =
3654                                         nextminlen + stripe_align -
3655                                         args.minlen - 1;
3656                         else
3657                                 args.minalignslop = 0;
3658                 }
3659         } else {
3660                 args.alignment = 1;
3661                 args.minalignslop = 0;
3662         }
3663         args.minleft = ap->minleft;
3664         args.wasdel = ap->wasdel;
3665         args.resv = XFS_AG_RESV_NONE;
3666         args.datatype = ap->datatype;
3667
3668         error = xfs_alloc_vextent(&args);
3669         if (error)
3670                 return error;
3671
3672         if (tryagain && args.fsbno == NULLFSBLOCK) {
3673                 /*
3674                  * Exact allocation failed. Now try with alignment
3675                  * turned on.
3676                  */
3677                 args.type = atype;
3678                 args.fsbno = ap->blkno;
3679                 args.alignment = stripe_align;
3680                 args.minlen = nextminlen;
3681                 args.minalignslop = 0;
3682                 isaligned = 1;
3683                 if ((error = xfs_alloc_vextent(&args)))
3684                         return error;
3685         }
3686         if (isaligned && args.fsbno == NULLFSBLOCK) {
3687                 /*
3688                  * allocation failed, so turn off alignment and
3689                  * try again.
3690                  */
3691                 args.type = atype;
3692                 args.fsbno = ap->blkno;
3693                 args.alignment = 0;
3694                 if ((error = xfs_alloc_vextent(&args)))
3695                         return error;
3696         }
3697         if (args.fsbno == NULLFSBLOCK && nullfb &&
3698             args.minlen > ap->minlen) {
3699                 args.minlen = ap->minlen;
3700                 args.type = XFS_ALLOCTYPE_START_BNO;
3701                 args.fsbno = ap->blkno;
3702                 if ((error = xfs_alloc_vextent(&args)))
3703                         return error;
3704         }
3705         if (args.fsbno == NULLFSBLOCK && nullfb) {
3706                 args.fsbno = 0;
3707                 args.type = XFS_ALLOCTYPE_FIRST_AG;
3708                 args.total = ap->minlen;
3709                 if ((error = xfs_alloc_vextent(&args)))
3710                         return error;
3711                 ap->tp->t_flags |= XFS_TRANS_LOWMODE;
3712         }
3713
3714         if (args.fsbno != NULLFSBLOCK) {
3715                 xfs_bmap_process_allocated_extent(ap, &args, orig_offset,
3716                         orig_length);
3717         } else {
3718                 ap->blkno = NULLFSBLOCK;
3719                 ap->length = 0;
3720         }
3721         return 0;
3722 }
3723
3724 /* Trim extent to fit a logical block range. */
3725 void
3726 xfs_trim_extent(
3727         struct xfs_bmbt_irec    *irec,
3728         xfs_fileoff_t           bno,
3729         xfs_filblks_t           len)
3730 {
3731         xfs_fileoff_t           distance;
3732         xfs_fileoff_t           end = bno + len;
3733
3734         if (irec->br_startoff + irec->br_blockcount <= bno ||
3735             irec->br_startoff >= end) {
3736                 irec->br_blockcount = 0;
3737                 return;
3738         }
3739
3740         if (irec->br_startoff < bno) {
3741                 distance = bno - irec->br_startoff;
3742                 if (isnullstartblock(irec->br_startblock))
3743                         irec->br_startblock = DELAYSTARTBLOCK;
3744                 if (irec->br_startblock != DELAYSTARTBLOCK &&
3745                     irec->br_startblock != HOLESTARTBLOCK)
3746                         irec->br_startblock += distance;
3747                 irec->br_startoff += distance;
3748                 irec->br_blockcount -= distance;
3749         }
3750
3751         if (end < irec->br_startoff + irec->br_blockcount) {
3752                 distance = irec->br_startoff + irec->br_blockcount - end;
3753                 irec->br_blockcount -= distance;
3754         }
3755 }
3756
3757 /*
3758  * Trim the returned map to the required bounds
3759  */
3760 STATIC void
3761 xfs_bmapi_trim_map(
3762         struct xfs_bmbt_irec    *mval,
3763         struct xfs_bmbt_irec    *got,
3764         xfs_fileoff_t           *bno,
3765         xfs_filblks_t           len,
3766         xfs_fileoff_t           obno,
3767         xfs_fileoff_t           end,
3768         int                     n,
3769         int                     flags)
3770 {
3771         if ((flags & XFS_BMAPI_ENTIRE) ||
3772             got->br_startoff + got->br_blockcount <= obno) {
3773                 *mval = *got;
3774                 if (isnullstartblock(got->br_startblock))
3775                         mval->br_startblock = DELAYSTARTBLOCK;
3776                 return;
3777         }
3778
3779         if (obno > *bno)
3780                 *bno = obno;
3781         ASSERT((*bno >= obno) || (n == 0));
3782         ASSERT(*bno < end);
3783         mval->br_startoff = *bno;
3784         if (isnullstartblock(got->br_startblock))
3785                 mval->br_startblock = DELAYSTARTBLOCK;
3786         else
3787                 mval->br_startblock = got->br_startblock +
3788                                         (*bno - got->br_startoff);
3789         /*
3790          * Return the minimum of what we got and what we asked for for
3791          * the length.  We can use the len variable here because it is
3792          * modified below and we could have been there before coming
3793          * here if the first part of the allocation didn't overlap what
3794          * was asked for.
3795          */
3796         mval->br_blockcount = XFS_FILBLKS_MIN(end - *bno,
3797                         got->br_blockcount - (*bno - got->br_startoff));
3798         mval->br_state = got->br_state;
3799         ASSERT(mval->br_blockcount <= len);
3800         return;
3801 }
3802
3803 /*
3804  * Update and validate the extent map to return
3805  */
3806 STATIC void
3807 xfs_bmapi_update_map(
3808         struct xfs_bmbt_irec    **map,
3809         xfs_fileoff_t           *bno,
3810         xfs_filblks_t           *len,
3811         xfs_fileoff_t           obno,
3812         xfs_fileoff_t           end,
3813         int                     *n,
3814         int                     flags)
3815 {
3816         xfs_bmbt_irec_t *mval = *map;
3817
3818         ASSERT((flags & XFS_BMAPI_ENTIRE) ||
3819                ((mval->br_startoff + mval->br_blockcount) <= end));
3820         ASSERT((flags & XFS_BMAPI_ENTIRE) || (mval->br_blockcount <= *len) ||
3821                (mval->br_startoff < obno));
3822
3823         *bno = mval->br_startoff + mval->br_blockcount;
3824         *len = end - *bno;
3825         if (*n > 0 && mval->br_startoff == mval[-1].br_startoff) {
3826                 /* update previous map with new information */
3827                 ASSERT(mval->br_startblock == mval[-1].br_startblock);
3828                 ASSERT(mval->br_blockcount > mval[-1].br_blockcount);
3829                 ASSERT(mval->br_state == mval[-1].br_state);
3830                 mval[-1].br_blockcount = mval->br_blockcount;
3831                 mval[-1].br_state = mval->br_state;
3832         } else if (*n > 0 && mval->br_startblock != DELAYSTARTBLOCK &&
3833                    mval[-1].br_startblock != DELAYSTARTBLOCK &&
3834                    mval[-1].br_startblock != HOLESTARTBLOCK &&
3835                    mval->br_startblock == mval[-1].br_startblock +
3836                                           mval[-1].br_blockcount &&
3837                    mval[-1].br_state == mval->br_state) {
3838                 ASSERT(mval->br_startoff ==
3839                        mval[-1].br_startoff + mval[-1].br_blockcount);
3840                 mval[-1].br_blockcount += mval->br_blockcount;
3841         } else if (*n > 0 &&
3842                    mval->br_startblock == DELAYSTARTBLOCK &&
3843                    mval[-1].br_startblock == DELAYSTARTBLOCK &&
3844                    mval->br_startoff ==
3845                    mval[-1].br_startoff + mval[-1].br_blockcount) {
3846                 mval[-1].br_blockcount += mval->br_blockcount;
3847                 mval[-1].br_state = mval->br_state;
3848         } else if (!((*n == 0) &&
3849                      ((mval->br_startoff + mval->br_blockcount) <=
3850                       obno))) {
3851                 mval++;
3852                 (*n)++;
3853         }
3854         *map = mval;
3855 }
3856
3857 /*
3858  * Map file blocks to filesystem blocks without allocation.
3859  */
3860 int
3861 xfs_bmapi_read(
3862         struct xfs_inode        *ip,
3863         xfs_fileoff_t           bno,
3864         xfs_filblks_t           len,
3865         struct xfs_bmbt_irec    *mval,
3866         int                     *nmap,
3867         int                     flags)
3868 {
3869         struct xfs_mount        *mp = ip->i_mount;
3870         int                     whichfork = xfs_bmapi_whichfork(flags);
3871         struct xfs_ifork        *ifp = XFS_IFORK_PTR(ip, whichfork);
3872         struct xfs_bmbt_irec    got;
3873         xfs_fileoff_t           obno;
3874         xfs_fileoff_t           end;
3875         struct xfs_iext_cursor  icur;
3876         int                     error;
3877         bool                    eof = false;
3878         int                     n = 0;
3879
3880         ASSERT(*nmap >= 1);
3881         ASSERT(!(flags & ~(XFS_BMAPI_ATTRFORK | XFS_BMAPI_ENTIRE)));
3882         ASSERT(xfs_isilocked(ip, XFS_ILOCK_SHARED|XFS_ILOCK_EXCL));
3883
3884         if (WARN_ON_ONCE(!ifp))
3885                 return -EFSCORRUPTED;
3886
3887         if (XFS_IS_CORRUPT(mp, !xfs_ifork_has_extents(ifp)) ||
3888             XFS_TEST_ERROR(false, mp, XFS_ERRTAG_BMAPIFORMAT))
3889                 return -EFSCORRUPTED;
3890
3891         if (xfs_is_shutdown(mp))
3892                 return -EIO;
3893
3894         XFS_STATS_INC(mp, xs_blk_mapr);
3895
3896         error = xfs_iread_extents(NULL, ip, whichfork);
3897         if (error)
3898                 return error;
3899
3900         if (!xfs_iext_lookup_extent(ip, ifp, bno, &icur, &got))
3901                 eof = true;
3902         end = bno + len;
3903         obno = bno;
3904
3905         while (bno < end && n < *nmap) {
3906                 /* Reading past eof, act as though there's a hole up to end. */
3907                 if (eof)
3908                         got.br_startoff = end;
3909                 if (got.br_startoff > bno) {
3910                         /* Reading in a hole.  */
3911                         mval->br_startoff = bno;
3912                         mval->br_startblock = HOLESTARTBLOCK;
3913                         mval->br_blockcount =
3914                                 XFS_FILBLKS_MIN(len, got.br_startoff - bno);
3915                         mval->br_state = XFS_EXT_NORM;
3916                         bno += mval->br_blockcount;
3917                         len -= mval->br_blockcount;
3918                         mval++;
3919                         n++;
3920                         continue;
3921                 }
3922
3923                 /* set up the extent map to return. */
3924                 xfs_bmapi_trim_map(mval, &got, &bno, len, obno, end, n, flags);
3925                 xfs_bmapi_update_map(&mval, &bno, &len, obno, end, &n, flags);
3926
3927                 /* If we're done, stop now. */
3928                 if (bno >= end || n >= *nmap)
3929                         break;
3930
3931                 /* Else go on to the next record. */
3932                 if (!xfs_iext_next_extent(ifp, &icur, &got))
3933                         eof = true;
3934         }
3935         *nmap = n;
3936         return 0;
3937 }
3938
3939 /*
3940  * Add a delayed allocation extent to an inode. Blocks are reserved from the
3941  * global pool and the extent inserted into the inode in-core extent tree.
3942  *
3943  * On entry, got refers to the first extent beyond the offset of the extent to
3944  * allocate or eof is specified if no such extent exists. On return, got refers
3945  * to the extent record that was inserted to the inode fork.
3946  *
3947  * Note that the allocated extent may have been merged with contiguous extents
3948  * during insertion into the inode fork. Thus, got does not reflect the current
3949  * state of the inode fork on return. If necessary, the caller can use lastx to
3950  * look up the updated record in the inode fork.
3951  */
3952 int
3953 xfs_bmapi_reserve_delalloc(
3954         struct xfs_inode        *ip,
3955         int                     whichfork,
3956         xfs_fileoff_t           off,
3957         xfs_filblks_t           len,
3958         xfs_filblks_t           prealloc,
3959         struct xfs_bmbt_irec    *got,
3960         struct xfs_iext_cursor  *icur,
3961         int                     eof)
3962 {
3963         struct xfs_mount        *mp = ip->i_mount;
3964         struct xfs_ifork        *ifp = XFS_IFORK_PTR(ip, whichfork);
3965         xfs_extlen_t            alen;
3966         xfs_extlen_t            indlen;
3967         int                     error;
3968         xfs_fileoff_t           aoff = off;
3969
3970         /*
3971          * Cap the alloc length. Keep track of prealloc so we know whether to
3972          * tag the inode before we return.
3973          */
3974         alen = XFS_FILBLKS_MIN(len + prealloc, MAXEXTLEN);
3975         if (!eof)
3976                 alen = XFS_FILBLKS_MIN(alen, got->br_startoff - aoff);
3977         if (prealloc && alen >= len)
3978                 prealloc = alen - len;
3979
3980         /* Figure out the extent size, adjust alen */
3981         if (whichfork == XFS_COW_FORK) {
3982                 struct xfs_bmbt_irec    prev;
3983                 xfs_extlen_t            extsz = xfs_get_cowextsz_hint(ip);
3984
3985                 if (!xfs_iext_peek_prev_extent(ifp, icur, &prev))
3986                         prev.br_startoff = NULLFILEOFF;
3987
3988                 error = xfs_bmap_extsize_align(mp, got, &prev, extsz, 0, eof,
3989                                                1, 0, &aoff, &alen);
3990                 ASSERT(!error);
3991         }
3992
3993         /*
3994          * Make a transaction-less quota reservation for delayed allocation
3995          * blocks.  This number gets adjusted later.  We return if we haven't
3996          * allocated blocks already inside this loop.
3997          */
3998         error = xfs_quota_reserve_blkres(ip, alen);
3999         if (error)
4000                 return error;
4001
4002         /*
4003          * Split changing sb for alen and indlen since they could be coming
4004          * from different places.
4005          */
4006         indlen = (xfs_extlen_t)xfs_bmap_worst_indlen(ip, alen);
4007         ASSERT(indlen > 0);
4008
4009         error = xfs_mod_fdblocks(mp, -((int64_t)alen), false);
4010         if (error)
4011                 goto out_unreserve_quota;
4012
4013         error = xfs_mod_fdblocks(mp, -((int64_t)indlen), false);
4014         if (error)
4015                 goto out_unreserve_blocks;
4016
4017
4018         ip->i_delayed_blks += alen;
4019         xfs_mod_delalloc(ip->i_mount, alen + indlen);
4020
4021         got->br_startoff = aoff;
4022         got->br_startblock = nullstartblock(indlen);
4023         got->br_blockcount = alen;
4024         got->br_state = XFS_EXT_NORM;
4025
4026         xfs_bmap_add_extent_hole_delay(ip, whichfork, icur, got);
4027
4028         /*
4029          * Tag the inode if blocks were preallocated. Note that COW fork
4030          * preallocation can occur at the start or end of the extent, even when
4031          * prealloc == 0, so we must also check the aligned offset and length.
4032          */
4033         if (whichfork == XFS_DATA_FORK && prealloc)
4034                 xfs_inode_set_eofblocks_tag(ip);
4035         if (whichfork == XFS_COW_FORK && (prealloc || aoff < off || alen > len))
4036                 xfs_inode_set_cowblocks_tag(ip);
4037
4038         return 0;
4039
4040 out_unreserve_blocks:
4041         xfs_mod_fdblocks(mp, alen, false);
4042 out_unreserve_quota:
4043         if (XFS_IS_QUOTA_ON(mp))
4044                 xfs_quota_unreserve_blkres(ip, alen);
4045         return error;
4046 }
4047
4048 static int
4049 xfs_bmap_alloc_userdata(
4050         struct xfs_bmalloca     *bma)
4051 {
4052         struct xfs_mount        *mp = bma->ip->i_mount;
4053         int                     whichfork = xfs_bmapi_whichfork(bma->flags);
4054         int                     error;
4055
4056         /*
4057          * Set the data type being allocated. For the data fork, the first data
4058          * in the file is treated differently to all other allocations. For the
4059          * attribute fork, we only need to ensure the allocated range is not on
4060          * the busy list.
4061          */
4062         bma->datatype = XFS_ALLOC_NOBUSY;
4063         if (whichfork == XFS_DATA_FORK) {
4064                 bma->datatype |= XFS_ALLOC_USERDATA;
4065                 if (bma->offset == 0)
4066                         bma->datatype |= XFS_ALLOC_INITIAL_USER_DATA;
4067
4068                 if (mp->m_dalign && bma->length >= mp->m_dalign) {
4069                         error = xfs_bmap_isaeof(bma, whichfork);
4070                         if (error)
4071                                 return error;
4072                 }
4073
4074                 if (XFS_IS_REALTIME_INODE(bma->ip))
4075                         return xfs_bmap_rtalloc(bma);
4076         }
4077
4078         if (unlikely(XFS_TEST_ERROR(false, mp,
4079                         XFS_ERRTAG_BMAP_ALLOC_MINLEN_EXTENT)))
4080                 return xfs_bmap_exact_minlen_extent_alloc(bma);
4081
4082         return xfs_bmap_btalloc(bma);
4083 }
4084
4085 static int
4086 xfs_bmapi_allocate(
4087         struct xfs_bmalloca     *bma)
4088 {
4089         struct xfs_mount        *mp = bma->ip->i_mount;
4090         int                     whichfork = xfs_bmapi_whichfork(bma->flags);
4091         struct xfs_ifork        *ifp = XFS_IFORK_PTR(bma->ip, whichfork);
4092         int                     tmp_logflags = 0;
4093         int                     error;
4094
4095         ASSERT(bma->length > 0);
4096
4097         /*
4098          * For the wasdelay case, we could also just allocate the stuff asked
4099          * for in this bmap call but that wouldn't be as good.
4100          */
4101         if (bma->wasdel) {
4102                 bma->length = (xfs_extlen_t)bma->got.br_blockcount;
4103                 bma->offset = bma->got.br_startoff;
4104                 if (!xfs_iext_peek_prev_extent(ifp, &bma->icur, &bma->prev))
4105                         bma->prev.br_startoff = NULLFILEOFF;
4106         } else {
4107                 bma->length = XFS_FILBLKS_MIN(bma->length, MAXEXTLEN);
4108                 if (!bma->eof)
4109                         bma->length = XFS_FILBLKS_MIN(bma->length,
4110                                         bma->got.br_startoff - bma->offset);
4111         }
4112
4113         if (bma->flags & XFS_BMAPI_CONTIG)
4114                 bma->minlen = bma->length;
4115         else
4116                 bma->minlen = 1;
4117
4118         if (bma->flags & XFS_BMAPI_METADATA) {
4119                 if (unlikely(XFS_TEST_ERROR(false, mp,
4120                                 XFS_ERRTAG_BMAP_ALLOC_MINLEN_EXTENT)))
4121                         error = xfs_bmap_exact_minlen_extent_alloc(bma);
4122                 else
4123                         error = xfs_bmap_btalloc(bma);
4124         } else {
4125                 error = xfs_bmap_alloc_userdata(bma);
4126         }
4127         if (error || bma->blkno == NULLFSBLOCK)
4128                 return error;
4129
4130         if (bma->flags & XFS_BMAPI_ZERO) {
4131                 error = xfs_zero_extent(bma->ip, bma->blkno, bma->length);
4132                 if (error)
4133                         return error;
4134         }
4135
4136         if (ifp->if_format == XFS_DINODE_FMT_BTREE && !bma->cur)
4137                 bma->cur = xfs_bmbt_init_cursor(mp, bma->tp, bma->ip, whichfork);
4138         /*
4139          * Bump the number of extents we've allocated
4140          * in this call.
4141          */
4142         bma->nallocs++;
4143
4144         if (bma->cur)
4145                 bma->cur->bc_ino.flags =
4146                         bma->wasdel ? XFS_BTCUR_BMBT_WASDEL : 0;
4147
4148         bma->got.br_startoff = bma->offset;
4149         bma->got.br_startblock = bma->blkno;
4150         bma->got.br_blockcount = bma->length;
4151         bma->got.br_state = XFS_EXT_NORM;
4152
4153         if (bma->flags & XFS_BMAPI_PREALLOC)
4154                 bma->got.br_state = XFS_EXT_UNWRITTEN;
4155
4156         if (bma->wasdel)
4157                 error = xfs_bmap_add_extent_delay_real(bma, whichfork);
4158         else
4159                 error = xfs_bmap_add_extent_hole_real(bma->tp, bma->ip,
4160                                 whichfork, &bma->icur, &bma->cur, &bma->got,
4161                                 &bma->logflags, bma->flags);
4162
4163         bma->logflags |= tmp_logflags;
4164         if (error)
4165                 return error;
4166
4167         /*
4168          * Update our extent pointer, given that xfs_bmap_add_extent_delay_real
4169          * or xfs_bmap_add_extent_hole_real might have merged it into one of
4170          * the neighbouring ones.
4171          */
4172         xfs_iext_get_extent(ifp, &bma->icur, &bma->got);
4173
4174         ASSERT(bma->got.br_startoff <= bma->offset);
4175         ASSERT(bma->got.br_startoff + bma->got.br_blockcount >=
4176                bma->offset + bma->length);
4177         ASSERT(bma->got.br_state == XFS_EXT_NORM ||
4178                bma->got.br_state == XFS_EXT_UNWRITTEN);
4179         return 0;
4180 }
4181
4182 STATIC int
4183 xfs_bmapi_convert_unwritten(
4184         struct xfs_bmalloca     *bma,
4185         struct xfs_bmbt_irec    *mval,
4186         xfs_filblks_t           len,
4187         int                     flags)
4188 {
4189         int                     whichfork = xfs_bmapi_whichfork(flags);
4190         struct xfs_ifork        *ifp = XFS_IFORK_PTR(bma->ip, whichfork);
4191         int                     tmp_logflags = 0;
4192         int                     error;
4193
4194         /* check if we need to do unwritten->real conversion */
4195         if (mval->br_state == XFS_EXT_UNWRITTEN &&
4196             (flags & XFS_BMAPI_PREALLOC))
4197                 return 0;
4198
4199         /* check if we need to do real->unwritten conversion */
4200         if (mval->br_state == XFS_EXT_NORM &&
4201             (flags & (XFS_BMAPI_PREALLOC | XFS_BMAPI_CONVERT)) !=
4202                         (XFS_BMAPI_PREALLOC | XFS_BMAPI_CONVERT))
4203                 return 0;
4204
4205         /*
4206          * Modify (by adding) the state flag, if writing.
4207          */
4208         ASSERT(mval->br_blockcount <= len);
4209         if (ifp->if_format == XFS_DINODE_FMT_BTREE && !bma->cur) {
4210                 bma->cur = xfs_bmbt_init_cursor(bma->ip->i_mount, bma->tp,
4211                                         bma->ip, whichfork);
4212         }
4213         mval->br_state = (mval->br_state == XFS_EXT_UNWRITTEN)
4214                                 ? XFS_EXT_NORM : XFS_EXT_UNWRITTEN;
4215
4216         /*
4217          * Before insertion into the bmbt, zero the range being converted
4218          * if required.
4219          */
4220         if (flags & XFS_BMAPI_ZERO) {
4221                 error = xfs_zero_extent(bma->ip, mval->br_startblock,
4222                                         mval->br_blockcount);
4223                 if (error)
4224                         return error;
4225         }
4226
4227         error = xfs_bmap_add_extent_unwritten_real(bma->tp, bma->ip, whichfork,
4228                         &bma->icur, &bma->cur, mval, &tmp_logflags);
4229         /*
4230          * Log the inode core unconditionally in the unwritten extent conversion
4231          * path because the conversion might not have done so (e.g., if the
4232          * extent count hasn't changed). We need to make sure the inode is dirty
4233          * in the transaction for the sake of fsync(), even if nothing has
4234          * changed, because fsync() will not force the log for this transaction
4235          * unless it sees the inode pinned.
4236          *
4237          * Note: If we're only converting cow fork extents, there aren't
4238          * any on-disk updates to make, so we don't need to log anything.
4239          */
4240         if (whichfork != XFS_COW_FORK)
4241                 bma->logflags |= tmp_logflags | XFS_ILOG_CORE;
4242         if (error)
4243                 return error;
4244
4245         /*
4246          * Update our extent pointer, given that
4247          * xfs_bmap_add_extent_unwritten_real might have merged it into one
4248          * of the neighbouring ones.
4249          */
4250         xfs_iext_get_extent(ifp, &bma->icur, &bma->got);
4251
4252         /*
4253          * We may have combined previously unwritten space with written space,
4254          * so generate another request.
4255          */
4256         if (mval->br_blockcount < len)
4257                 return -EAGAIN;
4258         return 0;
4259 }
4260
4261 static inline xfs_extlen_t
4262 xfs_bmapi_minleft(
4263         struct xfs_trans        *tp,
4264         struct xfs_inode        *ip,
4265         int                     fork)
4266 {
4267         struct xfs_ifork        *ifp = XFS_IFORK_PTR(ip, fork);
4268
4269         if (tp && tp->t_firstblock != NULLFSBLOCK)
4270                 return 0;
4271         if (ifp->if_format != XFS_DINODE_FMT_BTREE)
4272                 return 1;
4273         return be16_to_cpu(ifp->if_broot->bb_level) + 1;
4274 }
4275
4276 /*
4277  * Log whatever the flags say, even if error.  Otherwise we might miss detecting
4278  * a case where the data is changed, there's an error, and it's not logged so we
4279  * don't shutdown when we should.  Don't bother logging extents/btree changes if
4280  * we converted to the other format.
4281  */
4282 static void
4283 xfs_bmapi_finish(
4284         struct xfs_bmalloca     *bma,
4285         int                     whichfork,
4286         int                     error)
4287 {
4288         struct xfs_ifork        *ifp = XFS_IFORK_PTR(bma->ip, whichfork);
4289
4290         if ((bma->logflags & xfs_ilog_fext(whichfork)) &&
4291             ifp->if_format != XFS_DINODE_FMT_EXTENTS)
4292                 bma->logflags &= ~xfs_ilog_fext(whichfork);
4293         else if ((bma->logflags & xfs_ilog_fbroot(whichfork)) &&
4294                  ifp->if_format != XFS_DINODE_FMT_BTREE)
4295                 bma->logflags &= ~xfs_ilog_fbroot(whichfork);
4296
4297         if (bma->logflags)
4298                 xfs_trans_log_inode(bma->tp, bma->ip, bma->logflags);
4299         if (bma->cur)
4300                 xfs_btree_del_cursor(bma->cur, error);
4301 }
4302
4303 /*
4304  * Map file blocks to filesystem blocks, and allocate blocks or convert the
4305  * extent state if necessary.  Details behaviour is controlled by the flags
4306  * parameter.  Only allocates blocks from a single allocation group, to avoid
4307  * locking problems.
4308  */
4309 int
4310 xfs_bmapi_write(
4311         struct xfs_trans        *tp,            /* transaction pointer */
4312         struct xfs_inode        *ip,            /* incore inode */
4313         xfs_fileoff_t           bno,            /* starting file offs. mapped */
4314         xfs_filblks_t           len,            /* length to map in file */
4315         int                     flags,          /* XFS_BMAPI_... */
4316         xfs_extlen_t            total,          /* total blocks needed */
4317         struct xfs_bmbt_irec    *mval,          /* output: map values */
4318         int                     *nmap)          /* i/o: mval size/count */
4319 {
4320         struct xfs_bmalloca     bma = {
4321                 .tp             = tp,
4322                 .ip             = ip,
4323                 .total          = total,
4324         };
4325         struct xfs_mount        *mp = ip->i_mount;
4326         int                     whichfork = xfs_bmapi_whichfork(flags);
4327         struct xfs_ifork        *ifp = XFS_IFORK_PTR(ip, whichfork);
4328         xfs_fileoff_t           end;            /* end of mapped file region */
4329         bool                    eof = false;    /* after the end of extents */
4330         int                     error;          /* error return */
4331         int                     n;              /* current extent index */
4332         xfs_fileoff_t           obno;           /* old block number (offset) */
4333
4334 #ifdef DEBUG
4335         xfs_fileoff_t           orig_bno;       /* original block number value */
4336         int                     orig_flags;     /* original flags arg value */
4337         xfs_filblks_t           orig_len;       /* original value of len arg */
4338         struct xfs_bmbt_irec    *orig_mval;     /* original value of mval */
4339         int                     orig_nmap;      /* original value of *nmap */
4340
4341         orig_bno = bno;
4342         orig_len = len;
4343         orig_flags = flags;
4344         orig_mval = mval;
4345         orig_nmap = *nmap;
4346 #endif
4347
4348         ASSERT(*nmap >= 1);
4349         ASSERT(*nmap <= XFS_BMAP_MAX_NMAP);
4350         ASSERT(tp != NULL);
4351         ASSERT(len > 0);
4352         ASSERT(ifp->if_format != XFS_DINODE_FMT_LOCAL);
4353         ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
4354         ASSERT(!(flags & XFS_BMAPI_REMAP));
4355
4356         /* zeroing is for currently only for data extents, not metadata */
4357         ASSERT((flags & (XFS_BMAPI_METADATA | XFS_BMAPI_ZERO)) !=
4358                         (XFS_BMAPI_METADATA | XFS_BMAPI_ZERO));
4359         /*
4360          * we can allocate unwritten extents or pre-zero allocated blocks,
4361          * but it makes no sense to do both at once. This would result in
4362          * zeroing the unwritten extent twice, but it still being an
4363          * unwritten extent....
4364          */
4365         ASSERT((flags & (XFS_BMAPI_PREALLOC | XFS_BMAPI_ZERO)) !=
4366                         (XFS_BMAPI_PREALLOC | XFS_BMAPI_ZERO));
4367
4368         if (XFS_IS_CORRUPT(mp, !xfs_ifork_has_extents(ifp)) ||
4369             XFS_TEST_ERROR(false, mp, XFS_ERRTAG_BMAPIFORMAT)) {
4370                 return -EFSCORRUPTED;
4371         }
4372
4373         if (xfs_is_shutdown(mp))
4374                 return -EIO;
4375
4376         XFS_STATS_INC(mp, xs_blk_mapw);
4377
4378         error = xfs_iread_extents(tp, ip, whichfork);
4379         if (error)
4380                 goto error0;
4381
4382         if (!xfs_iext_lookup_extent(ip, ifp, bno, &bma.icur, &bma.got))
4383                 eof = true;
4384         if (!xfs_iext_peek_prev_extent(ifp, &bma.icur, &bma.prev))
4385                 bma.prev.br_startoff = NULLFILEOFF;
4386         bma.minleft = xfs_bmapi_minleft(tp, ip, whichfork);
4387
4388         n = 0;
4389         end = bno + len;
4390         obno = bno;
4391         while (bno < end && n < *nmap) {
4392                 bool                    need_alloc = false, wasdelay = false;
4393
4394                 /* in hole or beyond EOF? */
4395                 if (eof || bma.got.br_startoff > bno) {
4396                         /*
4397                          * CoW fork conversions should /never/ hit EOF or
4398                          * holes.  There should always be something for us
4399                          * to work on.
4400                          */
4401                         ASSERT(!((flags & XFS_BMAPI_CONVERT) &&
4402                                  (flags & XFS_BMAPI_COWFORK)));
4403
4404                         need_alloc = true;
4405                 } else if (isnullstartblock(bma.got.br_startblock)) {
4406                         wasdelay = true;
4407                 }
4408
4409                 /*
4410                  * First, deal with the hole before the allocated space
4411                  * that we found, if any.
4412                  */
4413                 if (need_alloc || wasdelay) {
4414                         bma.eof = eof;
4415                         bma.conv = !!(flags & XFS_BMAPI_CONVERT);
4416                         bma.wasdel = wasdelay;
4417                         bma.offset = bno;
4418                         bma.flags = flags;
4419
4420                         /*
4421                          * There's a 32/64 bit type mismatch between the
4422                          * allocation length request (which can be 64 bits in
4423                          * length) and the bma length request, which is
4424                          * xfs_extlen_t and therefore 32 bits. Hence we have to
4425                          * check for 32-bit overflows and handle them here.
4426                          */
4427                         if (len > (xfs_filblks_t)MAXEXTLEN)
4428                                 bma.length = MAXEXTLEN;
4429                         else
4430                                 bma.length = len;
4431
4432                         ASSERT(len > 0);
4433                         ASSERT(bma.length > 0);
4434                         error = xfs_bmapi_allocate(&bma);
4435                         if (error)
4436                                 goto error0;
4437                         if (bma.blkno == NULLFSBLOCK)
4438                                 break;
4439
4440                         /*
4441                          * If this is a CoW allocation, record the data in
4442                          * the refcount btree for orphan recovery.
4443                          */
4444                         if (whichfork == XFS_COW_FORK)
4445                                 xfs_refcount_alloc_cow_extent(tp, bma.blkno,
4446                                                 bma.length);
4447                 }
4448
4449                 /* Deal with the allocated space we found.  */
4450                 xfs_bmapi_trim_map(mval, &bma.got, &bno, len, obno,
4451                                                         end, n, flags);
4452
4453                 /* Execute unwritten extent conversion if necessary */
4454                 error = xfs_bmapi_convert_unwritten(&bma, mval, len, flags);
4455                 if (error == -EAGAIN)
4456                         continue;
4457                 if (error)
4458                         goto error0;
4459
4460                 /* update the extent map to return */
4461                 xfs_bmapi_update_map(&mval, &bno, &len, obno, end, &n, flags);
4462
4463                 /*
4464                  * If we're done, stop now.  Stop when we've allocated
4465                  * XFS_BMAP_MAX_NMAP extents no matter what.  Otherwise
4466                  * the transaction may get too big.
4467                  */
4468                 if (bno >= end || n >= *nmap || bma.nallocs >= *nmap)
4469                         break;
4470
4471                 /* Else go on to the next record. */
4472                 bma.prev = bma.got;
4473                 if (!xfs_iext_next_extent(ifp, &bma.icur, &bma.got))
4474                         eof = true;
4475         }
4476         *nmap = n;
4477
4478         error = xfs_bmap_btree_to_extents(tp, ip, bma.cur, &bma.logflags,
4479                         whichfork);
4480         if (error)
4481                 goto error0;
4482
4483         ASSERT(ifp->if_format != XFS_DINODE_FMT_BTREE ||
4484                ifp->if_nextents > XFS_IFORK_MAXEXT(ip, whichfork));
4485         xfs_bmapi_finish(&bma, whichfork, 0);
4486         xfs_bmap_validate_ret(orig_bno, orig_len, orig_flags, orig_mval,
4487                 orig_nmap, *nmap);
4488         return 0;
4489 error0:
4490         xfs_bmapi_finish(&bma, whichfork, error);
4491         return error;
4492 }
4493
4494 /*
4495  * Convert an existing delalloc extent to real blocks based on file offset. This
4496  * attempts to allocate the entire delalloc extent and may require multiple
4497  * invocations to allocate the target offset if a large enough physical extent
4498  * is not available.
4499  */
4500 int
4501 xfs_bmapi_convert_delalloc(
4502         struct xfs_inode        *ip,
4503         int                     whichfork,
4504         xfs_off_t               offset,
4505         struct iomap            *iomap,
4506         unsigned int            *seq)
4507 {
4508         struct xfs_ifork        *ifp = XFS_IFORK_PTR(ip, whichfork);
4509         struct xfs_mount        *mp = ip->i_mount;
4510         xfs_fileoff_t           offset_fsb = XFS_B_TO_FSBT(mp, offset);
4511         struct xfs_bmalloca     bma = { NULL };
4512         uint16_t                flags = 0;
4513         struct xfs_trans        *tp;
4514         int                     error;
4515
4516         if (whichfork == XFS_COW_FORK)
4517                 flags |= IOMAP_F_SHARED;
4518
4519         /*
4520          * Space for the extent and indirect blocks was reserved when the
4521          * delalloc extent was created so there's no need to do so here.
4522          */
4523         error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, 0, 0,
4524                                 XFS_TRANS_RESERVE, &tp);
4525         if (error)
4526                 return error;
4527
4528         xfs_ilock(ip, XFS_ILOCK_EXCL);
4529
4530         error = xfs_iext_count_may_overflow(ip, whichfork,
4531                         XFS_IEXT_ADD_NOSPLIT_CNT);
4532         if (error)
4533                 goto out_trans_cancel;
4534
4535         xfs_trans_ijoin(tp, ip, 0);
4536
4537         if (!xfs_iext_lookup_extent(ip, ifp, offset_fsb, &bma.icur, &bma.got) ||
4538             bma.got.br_startoff > offset_fsb) {
4539                 /*
4540                  * No extent found in the range we are trying to convert.  This
4541                  * should only happen for the COW fork, where another thread
4542                  * might have moved the extent to the data fork in the meantime.
4543                  */
4544                 WARN_ON_ONCE(whichfork != XFS_COW_FORK);
4545                 error = -EAGAIN;
4546                 goto out_trans_cancel;
4547         }
4548
4549         /*
4550          * If we find a real extent here we raced with another thread converting
4551          * the extent.  Just return the real extent at this offset.
4552          */
4553         if (!isnullstartblock(bma.got.br_startblock)) {
4554                 xfs_bmbt_to_iomap(ip, iomap, &bma.got, 0, flags);
4555                 *seq = READ_ONCE(ifp->if_seq);
4556                 goto out_trans_cancel;
4557         }
4558
4559         bma.tp = tp;
4560         bma.ip = ip;
4561         bma.wasdel = true;
4562         bma.offset = bma.got.br_startoff;
4563         bma.length = max_t(xfs_filblks_t, bma.got.br_blockcount, MAXEXTLEN);
4564         bma.minleft = xfs_bmapi_minleft(tp, ip, whichfork);
4565
4566         /*
4567          * When we're converting the delalloc reservations backing dirty pages
4568          * in the page cache, we must be careful about how we create the new
4569          * extents:
4570          *
4571          * New CoW fork extents are created unwritten, turned into real extents
4572          * when we're about to write the data to disk, and mapped into the data
4573          * fork after the write finishes.  End of story.
4574          *
4575          * New data fork extents must be mapped in as unwritten and converted
4576          * to real extents after the write succeeds to avoid exposing stale
4577          * disk contents if we crash.
4578          */
4579         bma.flags = XFS_BMAPI_PREALLOC;
4580         if (whichfork == XFS_COW_FORK)
4581                 bma.flags |= XFS_BMAPI_COWFORK;
4582
4583         if (!xfs_iext_peek_prev_extent(ifp, &bma.icur, &bma.prev))
4584                 bma.prev.br_startoff = NULLFILEOFF;
4585
4586         error = xfs_bmapi_allocate(&bma);
4587         if (error)
4588                 goto out_finish;
4589
4590         error = -ENOSPC;
4591         if (WARN_ON_ONCE(bma.blkno == NULLFSBLOCK))
4592                 goto out_finish;
4593         error = -EFSCORRUPTED;
4594         if (WARN_ON_ONCE(!xfs_valid_startblock(ip, bma.got.br_startblock)))
4595                 goto out_finish;
4596
4597         XFS_STATS_ADD(mp, xs_xstrat_bytes, XFS_FSB_TO_B(mp, bma.length));
4598         XFS_STATS_INC(mp, xs_xstrat_quick);
4599
4600         ASSERT(!isnullstartblock(bma.got.br_startblock));
4601         xfs_bmbt_to_iomap(ip, iomap, &bma.got, 0, flags);
4602         *seq = READ_ONCE(ifp->if_seq);
4603
4604         if (whichfork == XFS_COW_FORK)
4605                 xfs_refcount_alloc_cow_extent(tp, bma.blkno, bma.length);
4606
4607         error = xfs_bmap_btree_to_extents(tp, ip, bma.cur, &bma.logflags,
4608                         whichfork);
4609         if (error)
4610                 goto out_finish;
4611
4612         xfs_bmapi_finish(&bma, whichfork, 0);
4613         error = xfs_trans_commit(tp);
4614         xfs_iunlock(ip, XFS_ILOCK_EXCL);
4615         return error;
4616
4617 out_finish:
4618         xfs_bmapi_finish(&bma, whichfork, error);
4619 out_trans_cancel:
4620         xfs_trans_cancel(tp);
4621         xfs_iunlock(ip, XFS_ILOCK_EXCL);
4622         return error;
4623 }
4624
4625 int
4626 xfs_bmapi_remap(
4627         struct xfs_trans        *tp,
4628         struct xfs_inode        *ip,
4629         xfs_fileoff_t           bno,
4630         xfs_filblks_t           len,
4631         xfs_fsblock_t           startblock,
4632         int                     flags)
4633 {
4634         struct xfs_mount        *mp = ip->i_mount;
4635         struct xfs_ifork        *ifp;
4636         struct xfs_btree_cur    *cur = NULL;
4637         struct xfs_bmbt_irec    got;
4638         struct xfs_iext_cursor  icur;
4639         int                     whichfork = xfs_bmapi_whichfork(flags);
4640         int                     logflags = 0, error;
4641
4642         ifp = XFS_IFORK_PTR(ip, whichfork);
4643         ASSERT(len > 0);
4644         ASSERT(len <= (xfs_filblks_t)MAXEXTLEN);
4645         ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
4646         ASSERT(!(flags & ~(XFS_BMAPI_ATTRFORK | XFS_BMAPI_PREALLOC |
4647                            XFS_BMAPI_NORMAP)));
4648         ASSERT((flags & (XFS_BMAPI_ATTRFORK | XFS_BMAPI_PREALLOC)) !=
4649                         (XFS_BMAPI_ATTRFORK | XFS_BMAPI_PREALLOC));
4650
4651         if (XFS_IS_CORRUPT(mp, !xfs_ifork_has_extents(ifp)) ||
4652             XFS_TEST_ERROR(false, mp, XFS_ERRTAG_BMAPIFORMAT)) {
4653                 return -EFSCORRUPTED;
4654         }
4655
4656         if (xfs_is_shutdown(mp))
4657                 return -EIO;
4658
4659         error = xfs_iread_extents(tp, ip, whichfork);
4660         if (error)
4661                 return error;
4662
4663         if (xfs_iext_lookup_extent(ip, ifp, bno, &icur, &got)) {
4664                 /* make sure we only reflink into a hole. */
4665                 ASSERT(got.br_startoff > bno);
4666                 ASSERT(got.br_startoff - bno >= len);
4667         }
4668
4669         ip->i_nblocks += len;
4670         xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
4671
4672         if (ifp->if_format == XFS_DINODE_FMT_BTREE) {
4673                 cur = xfs_bmbt_init_cursor(mp, tp, ip, whichfork);
4674                 cur->bc_ino.flags = 0;
4675         }
4676
4677         got.br_startoff = bno;
4678         got.br_startblock = startblock;
4679         got.br_blockcount = len;
4680         if (flags & XFS_BMAPI_PREALLOC)
4681                 got.br_state = XFS_EXT_UNWRITTEN;
4682         else
4683                 got.br_state = XFS_EXT_NORM;
4684
4685         error = xfs_bmap_add_extent_hole_real(tp, ip, whichfork, &icur,
4686                         &cur, &got, &logflags, flags);
4687         if (error)
4688                 goto error0;
4689
4690         error = xfs_bmap_btree_to_extents(tp, ip, cur, &logflags, whichfork);
4691
4692 error0:
4693         if (ip->i_df.if_format != XFS_DINODE_FMT_EXTENTS)
4694                 logflags &= ~XFS_ILOG_DEXT;
4695         else if (ip->i_df.if_format != XFS_DINODE_FMT_BTREE)
4696                 logflags &= ~XFS_ILOG_DBROOT;
4697
4698         if (logflags)
4699                 xfs_trans_log_inode(tp, ip, logflags);
4700         if (cur)
4701                 xfs_btree_del_cursor(cur, error);
4702         return error;
4703 }
4704
4705 /*
4706  * When a delalloc extent is split (e.g., due to a hole punch), the original
4707  * indlen reservation must be shared across the two new extents that are left
4708  * behind.
4709  *
4710  * Given the original reservation and the worst case indlen for the two new
4711  * extents (as calculated by xfs_bmap_worst_indlen()), split the original
4712  * reservation fairly across the two new extents. If necessary, steal available
4713  * blocks from a deleted extent to make up a reservation deficiency (e.g., if
4714  * ores == 1). The number of stolen blocks is returned. The availability and
4715  * subsequent accounting of stolen blocks is the responsibility of the caller.
4716  */
4717 static xfs_filblks_t
4718 xfs_bmap_split_indlen(
4719         xfs_filblks_t                   ores,           /* original res. */
4720         xfs_filblks_t                   *indlen1,       /* ext1 worst indlen */
4721         xfs_filblks_t                   *indlen2,       /* ext2 worst indlen */
4722         xfs_filblks_t                   avail)          /* stealable blocks */
4723 {
4724         xfs_filblks_t                   len1 = *indlen1;
4725         xfs_filblks_t                   len2 = *indlen2;
4726         xfs_filblks_t                   nres = len1 + len2; /* new total res. */
4727         xfs_filblks_t                   stolen = 0;
4728         xfs_filblks_t                   resfactor;
4729
4730         /*
4731          * Steal as many blocks as we can to try and satisfy the worst case
4732          * indlen for both new extents.
4733          */
4734         if (ores < nres && avail)
4735                 stolen = XFS_FILBLKS_MIN(nres - ores, avail);
4736         ores += stolen;
4737
4738          /* nothing else to do if we've satisfied the new reservation */
4739         if (ores >= nres)
4740                 return stolen;
4741
4742         /*
4743          * We can't meet the total required reservation for the two extents.
4744          * Calculate the percent of the overall shortage between both extents
4745          * and apply this percentage to each of the requested indlen values.
4746          * This distributes the shortage fairly and reduces the chances that one
4747          * of the two extents is left with nothing when extents are repeatedly
4748          * split.
4749          */
4750         resfactor = (ores * 100);
4751         do_div(resfactor, nres);
4752         len1 *= resfactor;
4753         do_div(len1, 100);
4754         len2 *= resfactor;
4755         do_div(len2, 100);
4756         ASSERT(len1 + len2 <= ores);
4757         ASSERT(len1 < *indlen1 && len2 < *indlen2);
4758
4759         /*
4760          * Hand out the remainder to each extent. If one of the two reservations
4761          * is zero, we want to make sure that one gets a block first. The loop
4762          * below starts with len1, so hand len2 a block right off the bat if it
4763          * is zero.
4764          */
4765         ores -= (len1 + len2);
4766         ASSERT((*indlen1 - len1) + (*indlen2 - len2) >= ores);
4767         if (ores && !len2 && *indlen2) {
4768                 len2++;
4769                 ores--;
4770         }
4771         while (ores) {
4772                 if (len1 < *indlen1) {
4773                         len1++;
4774                         ores--;
4775                 }
4776                 if (!ores)
4777                         break;
4778                 if (len2 < *indlen2) {
4779                         len2++;
4780                         ores--;
4781                 }
4782         }
4783
4784         *indlen1 = len1;
4785         *indlen2 = len2;
4786
4787         return stolen;
4788 }
4789
4790 int
4791 xfs_bmap_del_extent_delay(
4792         struct xfs_inode        *ip,
4793         int                     whichfork,
4794         struct xfs_iext_cursor  *icur,
4795         struct xfs_bmbt_irec    *got,
4796         struct xfs_bmbt_irec    *del)
4797 {
4798         struct xfs_mount        *mp = ip->i_mount;
4799         struct xfs_ifork        *ifp = XFS_IFORK_PTR(ip, whichfork);
4800         struct xfs_bmbt_irec    new;
4801         int64_t                 da_old, da_new, da_diff = 0;
4802         xfs_fileoff_t           del_endoff, got_endoff;
4803         xfs_filblks_t           got_indlen, new_indlen, stolen;
4804         int                     state = xfs_bmap_fork_to_state(whichfork);
4805         int                     error = 0;
4806         bool                    isrt;
4807
4808         XFS_STATS_INC(mp, xs_del_exlist);
4809
4810         isrt = (whichfork == XFS_DATA_FORK) && XFS_IS_REALTIME_INODE(ip);
4811         del_endoff = del->br_startoff + del->br_blockcount;
4812         got_endoff = got->br_startoff + got->br_blockcount;
4813         da_old = startblockval(got->br_startblock);
4814         da_new = 0;
4815
4816         ASSERT(del->br_blockcount > 0);
4817         ASSERT(got->br_startoff <= del->br_startoff);
4818         ASSERT(got_endoff >= del_endoff);
4819
4820         if (isrt) {
4821                 uint64_t rtexts = XFS_FSB_TO_B(mp, del->br_blockcount);
4822
4823                 do_div(rtexts, mp->m_sb.sb_rextsize);
4824                 xfs_mod_frextents(mp, rtexts);
4825         }
4826
4827         /*
4828          * Update the inode delalloc counter now and wait to update the
4829          * sb counters as we might have to borrow some blocks for the
4830          * indirect block accounting.
4831          */
4832         ASSERT(!isrt);
4833         error = xfs_quota_unreserve_blkres(ip, del->br_blockcount);
4834         if (error)
4835                 return error;
4836         ip->i_delayed_blks -= del->br_blockcount;
4837
4838         if (got->br_startoff == del->br_startoff)
4839                 state |= BMAP_LEFT_FILLING;
4840         if (got_endoff == del_endoff)
4841                 state |= BMAP_RIGHT_FILLING;
4842
4843         switch (state & (BMAP_LEFT_FILLING | BMAP_RIGHT_FILLING)) {
4844         case BMAP_LEFT_FILLING | BMAP_RIGHT_FILLING:
4845                 /*
4846                  * Matches the whole extent.  Delete the entry.
4847                  */
4848                 xfs_iext_remove(ip, icur, state);
4849                 xfs_iext_prev(ifp, icur);
4850                 break;
4851         case BMAP_LEFT_FILLING:
4852                 /*
4853                  * Deleting the first part of the extent.
4854                  */
4855                 got->br_startoff = del_endoff;
4856                 got->br_blockcount -= del->br_blockcount;
4857                 da_new = XFS_FILBLKS_MIN(xfs_bmap_worst_indlen(ip,
4858                                 got->br_blockcount), da_old);
4859                 got->br_startblock = nullstartblock((int)da_new);
4860                 xfs_iext_update_extent(ip, state, icur, got);
4861                 break;
4862         case BMAP_RIGHT_FILLING:
4863                 /*
4864                  * Deleting the last part of the extent.
4865                  */
4866                 got->br_blockcount = got->br_blockcount - del->br_blockcount;
4867                 da_new = XFS_FILBLKS_MIN(xfs_bmap_worst_indlen(ip,
4868                                 got->br_blockcount), da_old);
4869                 got->br_startblock = nullstartblock((int)da_new);
4870                 xfs_iext_update_extent(ip, state, icur, got);
4871                 break;
4872         case 0:
4873                 /*
4874                  * Deleting the middle of the extent.
4875                  *
4876                  * Distribute the original indlen reservation across the two new
4877                  * extents.  Steal blocks from the deleted extent if necessary.
4878                  * Stealing blocks simply fudges the fdblocks accounting below.
4879                  * Warn if either of the new indlen reservations is zero as this
4880                  * can lead to delalloc problems.
4881                  */
4882                 got->br_blockcount = del->br_startoff - got->br_startoff;
4883                 got_indlen = xfs_bmap_worst_indlen(ip, got->br_blockcount);
4884
4885                 new.br_blockcount = got_endoff - del_endoff;
4886                 new_indlen = xfs_bmap_worst_indlen(ip, new.br_blockcount);
4887
4888                 WARN_ON_ONCE(!got_indlen || !new_indlen);
4889                 stolen = xfs_bmap_split_indlen(da_old, &got_indlen, &new_indlen,
4890                                                        del->br_blockcount);
4891
4892                 got->br_startblock = nullstartblock((int)got_indlen);
4893
4894                 new.br_startoff = del_endoff;
4895                 new.br_state = got->br_state;
4896                 new.br_startblock = nullstartblock((int)new_indlen);
4897
4898                 xfs_iext_update_extent(ip, state, icur, got);
4899                 xfs_iext_next(ifp, icur);
4900                 xfs_iext_insert(ip, icur, &new, state);
4901
4902                 da_new = got_indlen + new_indlen - stolen;
4903                 del->br_blockcount -= stolen;
4904                 break;
4905         }
4906
4907         ASSERT(da_old >= da_new);
4908         da_diff = da_old - da_new;
4909         if (!isrt)
4910                 da_diff += del->br_blockcount;
4911         if (da_diff) {
4912                 xfs_mod_fdblocks(mp, da_diff, false);
4913                 xfs_mod_delalloc(mp, -da_diff);
4914         }
4915         return error;
4916 }
4917
4918 void
4919 xfs_bmap_del_extent_cow(
4920         struct xfs_inode        *ip,
4921         struct xfs_iext_cursor  *icur,
4922         struct xfs_bmbt_irec    *got,
4923         struct xfs_bmbt_irec    *del)
4924 {
4925         struct xfs_mount        *mp = ip->i_mount;
4926         struct xfs_ifork        *ifp = XFS_IFORK_PTR(ip, XFS_COW_FORK);
4927         struct xfs_bmbt_irec    new;
4928         xfs_fileoff_t           del_endoff, got_endoff;
4929         int                     state = BMAP_COWFORK;
4930
4931         XFS_STATS_INC(mp, xs_del_exlist);
4932
4933         del_endoff = del->br_startoff + del->br_blockcount;
4934         got_endoff = got->br_startoff + got->br_blockcount;
4935
4936         ASSERT(del->br_blockcount > 0);
4937         ASSERT(got->br_startoff <= del->br_startoff);
4938         ASSERT(got_endoff >= del_endoff);
4939         ASSERT(!isnullstartblock(got->br_startblock));
4940
4941         if (got->br_startoff == del->br_startoff)
4942                 state |= BMAP_LEFT_FILLING;
4943         if (got_endoff == del_endoff)
4944                 state |= BMAP_RIGHT_FILLING;
4945
4946         switch (state & (BMAP_LEFT_FILLING | BMAP_RIGHT_FILLING)) {
4947         case BMAP_LEFT_FILLING | BMAP_RIGHT_FILLING:
4948                 /*
4949                  * Matches the whole extent.  Delete the entry.
4950                  */
4951                 xfs_iext_remove(ip, icur, state);
4952                 xfs_iext_prev(ifp, icur);
4953                 break;
4954         case BMAP_LEFT_FILLING:
4955                 /*
4956                  * Deleting the first part of the extent.
4957                  */
4958                 got->br_startoff = del_endoff;
4959                 got->br_blockcount -= del->br_blockcount;
4960                 got->br_startblock = del->br_startblock + del->br_blockcount;
4961                 xfs_iext_update_extent(ip, state, icur, got);
4962                 break;
4963         case BMAP_RIGHT_FILLING:
4964                 /*
4965                  * Deleting the last part of the extent.
4966                  */
4967                 got->br_blockcount -= del->br_blockcount;
4968                 xfs_iext_update_extent(ip, state, icur, got);
4969                 break;
4970         case 0:
4971                 /*
4972                  * Deleting the middle of the extent.
4973                  */
4974                 got->br_blockcount = del->br_startoff - got->br_startoff;
4975
4976                 new.br_startoff = del_endoff;
4977                 new.br_blockcount = got_endoff - del_endoff;
4978                 new.br_state = got->br_state;
4979                 new.br_startblock = del->br_startblock + del->br_blockcount;
4980
4981                 xfs_iext_update_extent(ip, state, icur, got);
4982                 xfs_iext_next(ifp, icur);
4983                 xfs_iext_insert(ip, icur, &new, state);
4984                 break;
4985         }
4986         ip->i_delayed_blks -= del->br_blockcount;
4987 }
4988
4989 /*
4990  * Called by xfs_bmapi to update file extent records and the btree
4991  * after removing space.
4992  */
4993 STATIC int                              /* error */
4994 xfs_bmap_del_extent_real(
4995         xfs_inode_t             *ip,    /* incore inode pointer */
4996         xfs_trans_t             *tp,    /* current transaction pointer */
4997         struct xfs_iext_cursor  *icur,
4998         struct xfs_btree_cur    *cur,   /* if null, not a btree */
4999         xfs_bmbt_irec_t         *del,   /* data to remove from extents */
5000         int                     *logflagsp, /* inode logging flags */
5001         int                     whichfork, /* data or attr fork */
5002         int                     bflags) /* bmapi flags */
5003 {
5004         xfs_fsblock_t           del_endblock=0; /* first block past del */
5005         xfs_fileoff_t           del_endoff;     /* first offset past del */
5006         int                     do_fx;  /* free extent at end of routine */
5007         int                     error;  /* error return value */
5008         int                     flags = 0;/* inode logging flags */
5009         struct xfs_bmbt_irec    got;    /* current extent entry */
5010         xfs_fileoff_t           got_endoff;     /* first offset past got */
5011         int                     i;      /* temp state */
5012         struct xfs_ifork        *ifp;   /* inode fork pointer */
5013         xfs_mount_t             *mp;    /* mount structure */
5014         xfs_filblks_t           nblks;  /* quota/sb block count */
5015         xfs_bmbt_irec_t         new;    /* new record to be inserted */
5016         /* REFERENCED */
5017         uint                    qfield; /* quota field to update */
5018         int                     state = xfs_bmap_fork_to_state(whichfork);
5019         struct xfs_bmbt_irec    old;
5020
5021         mp = ip->i_mount;
5022         XFS_STATS_INC(mp, xs_del_exlist);
5023
5024         ifp = XFS_IFORK_PTR(ip, whichfork);
5025         ASSERT(del->br_blockcount > 0);
5026         xfs_iext_get_extent(ifp, icur, &got);
5027         ASSERT(got.br_startoff <= del->br_startoff);
5028         del_endoff = del->br_startoff + del->br_blockcount;
5029         got_endoff = got.br_startoff + got.br_blockcount;
5030         ASSERT(got_endoff >= del_endoff);
5031         ASSERT(!isnullstartblock(got.br_startblock));
5032         qfield = 0;
5033         error = 0;
5034
5035         /*
5036          * If it's the case where the directory code is running with no block
5037          * reservation, and the deleted block is in the middle of its extent,
5038          * and the resulting insert of an extent would cause transformation to
5039          * btree format, then reject it.  The calling code will then swap blocks
5040          * around instead.  We have to do this now, rather than waiting for the
5041          * conversion to btree format, since the transaction will be dirty then.
5042          */
5043         if (tp->t_blk_res == 0 &&
5044             ifp->if_format == XFS_DINODE_FMT_EXTENTS &&
5045             ifp->if_nextents >= XFS_IFORK_MAXEXT(ip, whichfork) &&
5046             del->br_startoff > got.br_startoff && del_endoff < got_endoff)
5047                 return -ENOSPC;
5048
5049         flags = XFS_ILOG_CORE;
5050         if (whichfork == XFS_DATA_FORK && XFS_IS_REALTIME_INODE(ip)) {
5051                 xfs_filblks_t   len;
5052                 xfs_extlen_t    mod;
5053
5054                 len = div_u64_rem(del->br_blockcount, mp->m_sb.sb_rextsize,
5055                                   &mod);
5056                 ASSERT(mod == 0);
5057
5058                 if (!(bflags & XFS_BMAPI_REMAP)) {
5059                         xfs_fsblock_t   bno;
5060
5061                         bno = div_u64_rem(del->br_startblock,
5062                                         mp->m_sb.sb_rextsize, &mod);
5063                         ASSERT(mod == 0);
5064
5065                         error = xfs_rtfree_extent(tp, bno, (xfs_extlen_t)len);
5066                         if (error)
5067                                 goto done;
5068                 }
5069
5070                 do_fx = 0;
5071                 nblks = len * mp->m_sb.sb_rextsize;
5072                 qfield = XFS_TRANS_DQ_RTBCOUNT;
5073         } else {
5074                 do_fx = 1;
5075                 nblks = del->br_blockcount;
5076                 qfield = XFS_TRANS_DQ_BCOUNT;
5077         }
5078
5079         del_endblock = del->br_startblock + del->br_blockcount;
5080         if (cur) {
5081                 error = xfs_bmbt_lookup_eq(cur, &got, &i);
5082                 if (error)
5083                         goto done;
5084                 if (XFS_IS_CORRUPT(mp, i != 1)) {
5085                         error = -EFSCORRUPTED;
5086                         goto done;
5087                 }
5088         }
5089
5090         if (got.br_startoff == del->br_startoff)
5091                 state |= BMAP_LEFT_FILLING;
5092         if (got_endoff == del_endoff)
5093                 state |= BMAP_RIGHT_FILLING;
5094
5095         switch (state & (BMAP_LEFT_FILLING | BMAP_RIGHT_FILLING)) {
5096         case BMAP_LEFT_FILLING | BMAP_RIGHT_FILLING:
5097                 /*
5098                  * Matches the whole extent.  Delete the entry.
5099                  */
5100                 xfs_iext_remove(ip, icur, state);
5101                 xfs_iext_prev(ifp, icur);
5102                 ifp->if_nextents--;
5103
5104                 flags |= XFS_ILOG_CORE;
5105                 if (!cur) {
5106                         flags |= xfs_ilog_fext(whichfork);
5107                         break;
5108                 }
5109                 if ((error = xfs_btree_delete(cur, &i)))
5110                         goto done;
5111                 if (XFS_IS_CORRUPT(mp, i != 1)) {
5112                         error = -EFSCORRUPTED;
5113                         goto done;
5114                 }
5115                 break;
5116         case BMAP_LEFT_FILLING:
5117                 /*
5118                  * Deleting the first part of the extent.
5119                  */
5120                 got.br_startoff = del_endoff;
5121                 got.br_startblock = del_endblock;
5122                 got.br_blockcount -= del->br_blockcount;
5123                 xfs_iext_update_extent(ip, state, icur, &got);
5124                 if (!cur) {
5125                         flags |= xfs_ilog_fext(whichfork);
5126                         break;
5127                 }
5128                 error = xfs_bmbt_update(cur, &got);
5129                 if (error)
5130                         goto done;
5131                 break;
5132         case BMAP_RIGHT_FILLING:
5133                 /*
5134                  * Deleting the last part of the extent.
5135                  */
5136                 got.br_blockcount -= del->br_blockcount;
5137                 xfs_iext_update_extent(ip, state, icur, &got);
5138                 if (!cur) {
5139                         flags |= xfs_ilog_fext(whichfork);
5140                         break;
5141                 }
5142                 error = xfs_bmbt_update(cur, &got);
5143                 if (error)
5144                         goto done;
5145                 break;
5146         case 0:
5147                 /*
5148                  * Deleting the middle of the extent.
5149                  */
5150
5151                 /*
5152                  * For directories, -ENOSPC is returned since a directory entry
5153                  * remove operation must not fail due to low extent count
5154                  * availability. -ENOSPC will be handled by higher layers of XFS
5155                  * by letting the corresponding empty Data/Free blocks to linger
5156                  * until a future remove operation. Dabtree blocks would be
5157                  * swapped with the last block in the leaf space and then the
5158                  * new last block will be unmapped.
5159                  *
5160                  * The above logic also applies to the source directory entry of
5161                  * a rename operation.
5162                  */
5163                 error = xfs_iext_count_may_overflow(ip, whichfork, 1);
5164                 if (error) {
5165                         ASSERT(S_ISDIR(VFS_I(ip)->i_mode) &&
5166                                 whichfork == XFS_DATA_FORK);
5167                         error = -ENOSPC;
5168                         goto done;
5169                 }
5170
5171                 old = got;
5172
5173                 got.br_blockcount = del->br_startoff - got.br_startoff;
5174                 xfs_iext_update_extent(ip, state, icur, &got);
5175
5176                 new.br_startoff = del_endoff;
5177                 new.br_blockcount = got_endoff - del_endoff;
5178                 new.br_state = got.br_state;
5179                 new.br_startblock = del_endblock;
5180
5181                 flags |= XFS_ILOG_CORE;
5182                 if (cur) {
5183                         error = xfs_bmbt_update(cur, &got);
5184                         if (error)
5185                                 goto done;
5186                         error = xfs_btree_increment(cur, 0, &i);
5187                         if (error)
5188                                 goto done;
5189                         cur->bc_rec.b = new;
5190                         error = xfs_btree_insert(cur, &i);
5191                         if (error && error != -ENOSPC)
5192                                 goto done;
5193                         /*
5194                          * If get no-space back from btree insert, it tried a
5195                          * split, and we have a zero block reservation.  Fix up
5196                          * our state and return the error.
5197                          */
5198                         if (error == -ENOSPC) {
5199                                 /*
5200                                  * Reset the cursor, don't trust it after any
5201                                  * insert operation.
5202                                  */
5203                                 error = xfs_bmbt_lookup_eq(cur, &got, &i);
5204                                 if (error)
5205                                         goto done;
5206                                 if (XFS_IS_CORRUPT(mp, i != 1)) {
5207                                         error = -EFSCORRUPTED;
5208                                         goto done;
5209                                 }
5210                                 /*
5211                                  * Update the btree record back
5212                                  * to the original value.
5213                                  */
5214                                 error = xfs_bmbt_update(cur, &old);
5215                                 if (error)
5216                                         goto done;
5217                                 /*
5218                                  * Reset the extent record back
5219                                  * to the original value.
5220                                  */
5221                                 xfs_iext_update_extent(ip, state, icur, &old);
5222                                 flags = 0;
5223                                 error = -ENOSPC;
5224                                 goto done;
5225                         }
5226                         if (XFS_IS_CORRUPT(mp, i != 1)) {
5227                                 error = -EFSCORRUPTED;
5228                                 goto done;
5229                         }
5230                 } else
5231                         flags |= xfs_ilog_fext(whichfork);
5232
5233                 ifp->if_nextents++;
5234                 xfs_iext_next(ifp, icur);
5235                 xfs_iext_insert(ip, icur, &new, state);
5236                 break;
5237         }
5238
5239         /* remove reverse mapping */
5240         xfs_rmap_unmap_extent(tp, ip, whichfork, del);
5241
5242         /*
5243          * If we need to, add to list of extents to delete.
5244          */
5245         if (do_fx && !(bflags & XFS_BMAPI_REMAP)) {
5246                 if (xfs_is_reflink_inode(ip) && whichfork == XFS_DATA_FORK) {
5247                         xfs_refcount_decrease_extent(tp, del);
5248                 } else {
5249                         __xfs_free_extent_later(tp, del->br_startblock,
5250                                         del->br_blockcount, NULL,
5251                                         (bflags & XFS_BMAPI_NODISCARD) ||
5252                                         del->br_state == XFS_EXT_UNWRITTEN);
5253                 }
5254         }
5255
5256         /*
5257          * Adjust inode # blocks in the file.
5258          */
5259         if (nblks)
5260                 ip->i_nblocks -= nblks;
5261         /*
5262          * Adjust quota data.
5263          */
5264         if (qfield && !(bflags & XFS_BMAPI_REMAP))
5265                 xfs_trans_mod_dquot_byino(tp, ip, qfield, (long)-nblks);
5266
5267 done:
5268         *logflagsp = flags;
5269         return error;
5270 }
5271
5272 /*
5273  * Unmap (remove) blocks from a file.
5274  * If nexts is nonzero then the number of extents to remove is limited to
5275  * that value.  If not all extents in the block range can be removed then
5276  * *done is set.
5277  */
5278 int                                             /* error */
5279 __xfs_bunmapi(
5280         struct xfs_trans        *tp,            /* transaction pointer */
5281         struct xfs_inode        *ip,            /* incore inode */
5282         xfs_fileoff_t           start,          /* first file offset deleted */
5283         xfs_filblks_t           *rlen,          /* i/o: amount remaining */
5284         int                     flags,          /* misc flags */
5285         xfs_extnum_t            nexts)          /* number of extents max */
5286 {
5287         struct xfs_btree_cur    *cur;           /* bmap btree cursor */
5288         struct xfs_bmbt_irec    del;            /* extent being deleted */
5289         int                     error;          /* error return value */
5290         xfs_extnum_t            extno;          /* extent number in list */
5291         struct xfs_bmbt_irec    got;            /* current extent record */
5292         struct xfs_ifork        *ifp;           /* inode fork pointer */
5293         int                     isrt;           /* freeing in rt area */
5294         int                     logflags;       /* transaction logging flags */
5295         xfs_extlen_t            mod;            /* rt extent offset */
5296         struct xfs_mount        *mp = ip->i_mount;
5297         int                     tmp_logflags;   /* partial logging flags */
5298         int                     wasdel;         /* was a delayed alloc extent */
5299         int                     whichfork;      /* data or attribute fork */
5300         xfs_fsblock_t           sum;
5301         xfs_filblks_t           len = *rlen;    /* length to unmap in file */
5302         xfs_fileoff_t           max_len;
5303         xfs_fileoff_t           end;
5304         struct xfs_iext_cursor  icur;
5305         bool                    done = false;
5306
5307         trace_xfs_bunmap(ip, start, len, flags, _RET_IP_);
5308
5309         whichfork = xfs_bmapi_whichfork(flags);
5310         ASSERT(whichfork != XFS_COW_FORK);
5311         ifp = XFS_IFORK_PTR(ip, whichfork);
5312         if (XFS_IS_CORRUPT(mp, !xfs_ifork_has_extents(ifp)))
5313                 return -EFSCORRUPTED;
5314         if (xfs_is_shutdown(mp))
5315                 return -EIO;
5316
5317         ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
5318         ASSERT(len > 0);
5319         ASSERT(nexts >= 0);
5320
5321         /*
5322          * Guesstimate how many blocks we can unmap without running the risk of
5323          * blowing out the transaction with a mix of EFIs and reflink
5324          * adjustments.
5325          */
5326         if (tp && xfs_is_reflink_inode(ip) && whichfork == XFS_DATA_FORK)
5327                 max_len = min(len, xfs_refcount_max_unmap(tp->t_log_res));
5328         else
5329                 max_len = len;
5330
5331         error = xfs_iread_extents(tp, ip, whichfork);
5332         if (error)
5333                 return error;
5334
5335         if (xfs_iext_count(ifp) == 0) {
5336                 *rlen = 0;
5337                 return 0;
5338         }
5339         XFS_STATS_INC(mp, xs_blk_unmap);
5340         isrt = (whichfork == XFS_DATA_FORK) && XFS_IS_REALTIME_INODE(ip);
5341         end = start + len;
5342
5343         if (!xfs_iext_lookup_extent_before(ip, ifp, &end, &icur, &got)) {
5344                 *rlen = 0;
5345                 return 0;
5346         }
5347         end--;
5348
5349         logflags = 0;
5350         if (ifp->if_format == XFS_DINODE_FMT_BTREE) {
5351                 ASSERT(ifp->if_format == XFS_DINODE_FMT_BTREE);
5352                 cur = xfs_bmbt_init_cursor(mp, tp, ip, whichfork);
5353                 cur->bc_ino.flags = 0;
5354         } else
5355                 cur = NULL;
5356
5357         if (isrt) {
5358                 /*
5359                  * Synchronize by locking the bitmap inode.
5360                  */
5361                 xfs_ilock(mp->m_rbmip, XFS_ILOCK_EXCL|XFS_ILOCK_RTBITMAP);
5362                 xfs_trans_ijoin(tp, mp->m_rbmip, XFS_ILOCK_EXCL);
5363                 xfs_ilock(mp->m_rsumip, XFS_ILOCK_EXCL|XFS_ILOCK_RTSUM);
5364                 xfs_trans_ijoin(tp, mp->m_rsumip, XFS_ILOCK_EXCL);
5365         }
5366
5367         extno = 0;
5368         while (end != (xfs_fileoff_t)-1 && end >= start &&
5369                (nexts == 0 || extno < nexts) && max_len > 0) {
5370                 /*
5371                  * Is the found extent after a hole in which end lives?
5372                  * Just back up to the previous extent, if so.
5373                  */
5374                 if (got.br_startoff > end &&
5375                     !xfs_iext_prev_extent(ifp, &icur, &got)) {
5376                         done = true;
5377                         break;
5378                 }
5379                 /*
5380                  * Is the last block of this extent before the range
5381                  * we're supposed to delete?  If so, we're done.
5382                  */
5383                 end = XFS_FILEOFF_MIN(end,
5384                         got.br_startoff + got.br_blockcount - 1);
5385                 if (end < start)
5386                         break;
5387                 /*
5388                  * Then deal with the (possibly delayed) allocated space
5389                  * we found.
5390                  */
5391                 del = got;
5392                 wasdel = isnullstartblock(del.br_startblock);
5393
5394                 if (got.br_startoff < start) {
5395                         del.br_startoff = start;
5396                         del.br_blockcount -= start - got.br_startoff;
5397                         if (!wasdel)
5398                                 del.br_startblock += start - got.br_startoff;
5399                 }
5400                 if (del.br_startoff + del.br_blockcount > end + 1)
5401                         del.br_blockcount = end + 1 - del.br_startoff;
5402
5403                 /* How much can we safely unmap? */
5404                 if (max_len < del.br_blockcount) {
5405                         del.br_startoff += del.br_blockcount - max_len;
5406                         if (!wasdel)
5407                                 del.br_startblock += del.br_blockcount - max_len;
5408                         del.br_blockcount = max_len;
5409                 }
5410
5411                 if (!isrt)
5412                         goto delete;
5413
5414                 sum = del.br_startblock + del.br_blockcount;
5415                 div_u64_rem(sum, mp->m_sb.sb_rextsize, &mod);
5416                 if (mod) {
5417                         /*
5418                          * Realtime extent not lined up at the end.
5419                          * The extent could have been split into written
5420                          * and unwritten pieces, or we could just be
5421                          * unmapping part of it.  But we can't really
5422                          * get rid of part of a realtime extent.
5423                          */
5424                         if (del.br_state == XFS_EXT_UNWRITTEN) {
5425                                 /*
5426                                  * This piece is unwritten, or we're not
5427                                  * using unwritten extents.  Skip over it.
5428                                  */
5429                                 ASSERT(end >= mod);
5430                                 end -= mod > del.br_blockcount ?
5431                                         del.br_blockcount : mod;
5432                                 if (end < got.br_startoff &&
5433                                     !xfs_iext_prev_extent(ifp, &icur, &got)) {
5434                                         done = true;
5435                                         break;
5436                                 }
5437                                 continue;
5438                         }
5439                         /*
5440                          * It's written, turn it unwritten.
5441                          * This is better than zeroing it.
5442                          */
5443                         ASSERT(del.br_state == XFS_EXT_NORM);
5444                         ASSERT(tp->t_blk_res > 0);
5445                         /*
5446                          * If this spans a realtime extent boundary,
5447                          * chop it back to the start of the one we end at.
5448                          */
5449                         if (del.br_blockcount > mod) {
5450                                 del.br_startoff += del.br_blockcount - mod;
5451                                 del.br_startblock += del.br_blockcount - mod;
5452                                 del.br_blockcount = mod;
5453                         }
5454                         del.br_state = XFS_EXT_UNWRITTEN;
5455                         error = xfs_bmap_add_extent_unwritten_real(tp, ip,
5456                                         whichfork, &icur, &cur, &del,
5457                                         &logflags);
5458                         if (error)
5459                                 goto error0;
5460                         goto nodelete;
5461                 }
5462                 div_u64_rem(del.br_startblock, mp->m_sb.sb_rextsize, &mod);
5463                 if (mod) {
5464                         xfs_extlen_t off = mp->m_sb.sb_rextsize - mod;
5465
5466                         /*
5467                          * Realtime extent is lined up at the end but not
5468                          * at the front.  We'll get rid of full extents if
5469                          * we can.
5470                          */
5471                         if (del.br_blockcount > off) {
5472                                 del.br_blockcount -= off;
5473                                 del.br_startoff += off;
5474                                 del.br_startblock += off;
5475                         } else if (del.br_startoff == start &&
5476                                    (del.br_state == XFS_EXT_UNWRITTEN ||
5477                                     tp->t_blk_res == 0)) {
5478                                 /*
5479                                  * Can't make it unwritten.  There isn't
5480                                  * a full extent here so just skip it.
5481                                  */
5482                                 ASSERT(end >= del.br_blockcount);
5483                                 end -= del.br_blockcount;
5484                                 if (got.br_startoff > end &&
5485                                     !xfs_iext_prev_extent(ifp, &icur, &got)) {
5486                                         done = true;
5487                                         break;
5488                                 }
5489                                 continue;
5490                         } else if (del.br_state == XFS_EXT_UNWRITTEN) {
5491                                 struct xfs_bmbt_irec    prev;
5492                                 xfs_fileoff_t           unwrite_start;
5493
5494                                 /*
5495                                  * This one is already unwritten.
5496                                  * It must have a written left neighbor.
5497                                  * Unwrite the killed part of that one and
5498                                  * try again.
5499                                  */
5500                                 if (!xfs_iext_prev_extent(ifp, &icur, &prev))
5501                                         ASSERT(0);
5502                                 ASSERT(prev.br_state == XFS_EXT_NORM);
5503                                 ASSERT(!isnullstartblock(prev.br_startblock));
5504                                 ASSERT(del.br_startblock ==
5505                                        prev.br_startblock + prev.br_blockcount);
5506                                 unwrite_start = max3(start,
5507                                                      del.br_startoff - mod,
5508                                                      prev.br_startoff);
5509                                 mod = unwrite_start - prev.br_startoff;
5510                                 prev.br_startoff = unwrite_start;
5511                                 prev.br_startblock += mod;
5512                                 prev.br_blockcount -= mod;
5513                                 prev.br_state = XFS_EXT_UNWRITTEN;
5514                                 error = xfs_bmap_add_extent_unwritten_real(tp,
5515                                                 ip, whichfork, &icur, &cur,
5516                                                 &prev, &logflags);
5517                                 if (error)
5518                                         goto error0;
5519                                 goto nodelete;
5520                         } else {
5521                                 ASSERT(del.br_state == XFS_EXT_NORM);
5522                                 del.br_state = XFS_EXT_UNWRITTEN;
5523                                 error = xfs_bmap_add_extent_unwritten_real(tp,
5524                                                 ip, whichfork, &icur, &cur,
5525                                                 &del, &logflags);
5526                                 if (error)
5527                                         goto error0;
5528                                 goto nodelete;
5529                         }
5530                 }
5531
5532 delete:
5533                 if (wasdel) {
5534                         error = xfs_bmap_del_extent_delay(ip, whichfork, &icur,
5535                                         &got, &del);
5536                 } else {
5537                         error = xfs_bmap_del_extent_real(ip, tp, &icur, cur,
5538                                         &del, &tmp_logflags, whichfork,
5539                                         flags);
5540                         logflags |= tmp_logflags;
5541                 }
5542
5543                 if (error)
5544                         goto error0;
5545
5546                 max_len -= del.br_blockcount;
5547                 end = del.br_startoff - 1;
5548 nodelete:
5549                 /*
5550                  * If not done go on to the next (previous) record.
5551                  */
5552                 if (end != (xfs_fileoff_t)-1 && end >= start) {
5553                         if (!xfs_iext_get_extent(ifp, &icur, &got) ||
5554                             (got.br_startoff > end &&
5555                              !xfs_iext_prev_extent(ifp, &icur, &got))) {
5556                                 done = true;
5557                                 break;
5558                         }
5559                         extno++;
5560                 }
5561         }
5562         if (done || end == (xfs_fileoff_t)-1 || end < start)
5563                 *rlen = 0;
5564         else
5565                 *rlen = end - start + 1;
5566
5567         /*
5568          * Convert to a btree if necessary.
5569          */
5570         if (xfs_bmap_needs_btree(ip, whichfork)) {
5571                 ASSERT(cur == NULL);
5572                 error = xfs_bmap_extents_to_btree(tp, ip, &cur, 0,
5573                                 &tmp_logflags, whichfork);
5574                 logflags |= tmp_logflags;
5575         } else {
5576                 error = xfs_bmap_btree_to_extents(tp, ip, cur, &logflags,
5577                         whichfork);
5578         }
5579
5580 error0:
5581         /*
5582          * Log everything.  Do this after conversion, there's no point in
5583          * logging the extent records if we've converted to btree format.
5584          */
5585         if ((logflags & xfs_ilog_fext(whichfork)) &&
5586             ifp->if_format != XFS_DINODE_FMT_EXTENTS)
5587                 logflags &= ~xfs_ilog_fext(whichfork);
5588         else if ((logflags & xfs_ilog_fbroot(whichfork)) &&
5589                  ifp->if_format != XFS_DINODE_FMT_BTREE)
5590                 logflags &= ~xfs_ilog_fbroot(whichfork);
5591         /*
5592          * Log inode even in the error case, if the transaction
5593          * is dirty we'll need to shut down the filesystem.
5594          */
5595         if (logflags)
5596                 xfs_trans_log_inode(tp, ip, logflags);
5597         if (cur) {
5598                 if (!error)
5599                         cur->bc_ino.allocated = 0;
5600                 xfs_btree_del_cursor(cur, error);
5601         }
5602         return error;
5603 }
5604
5605 /* Unmap a range of a file. */
5606 int
5607 xfs_bunmapi(
5608         xfs_trans_t             *tp,
5609         struct xfs_inode        *ip,
5610         xfs_fileoff_t           bno,
5611         xfs_filblks_t           len,
5612         int                     flags,
5613         xfs_extnum_t            nexts,
5614         int                     *done)
5615 {
5616         int                     error;
5617
5618         error = __xfs_bunmapi(tp, ip, bno, &len, flags, nexts);
5619         *done = (len == 0);
5620         return error;
5621 }
5622
5623 /*
5624  * Determine whether an extent shift can be accomplished by a merge with the
5625  * extent that precedes the target hole of the shift.
5626  */
5627 STATIC bool
5628 xfs_bmse_can_merge(
5629         struct xfs_bmbt_irec    *left,  /* preceding extent */
5630         struct xfs_bmbt_irec    *got,   /* current extent to shift */
5631         xfs_fileoff_t           shift)  /* shift fsb */
5632 {
5633         xfs_fileoff_t           startoff;
5634
5635         startoff = got->br_startoff - shift;
5636
5637         /*
5638          * The extent, once shifted, must be adjacent in-file and on-disk with
5639          * the preceding extent.
5640          */
5641         if ((left->br_startoff + left->br_blockcount != startoff) ||
5642             (left->br_startblock + left->br_blockcount != got->br_startblock) ||
5643             (left->br_state != got->br_state) ||
5644             (left->br_blockcount + got->br_blockcount > MAXEXTLEN))
5645                 return false;
5646
5647         return true;
5648 }
5649
5650 /*
5651  * A bmap extent shift adjusts the file offset of an extent to fill a preceding
5652  * hole in the file. If an extent shift would result in the extent being fully
5653  * adjacent to the extent that currently precedes the hole, we can merge with
5654  * the preceding extent rather than do the shift.
5655  *
5656  * This function assumes the caller has verified a shift-by-merge is possible
5657  * with the provided extents via xfs_bmse_can_merge().
5658  */
5659 STATIC int
5660 xfs_bmse_merge(
5661         struct xfs_trans                *tp,
5662         struct xfs_inode                *ip,
5663         int                             whichfork,
5664         xfs_fileoff_t                   shift,          /* shift fsb */
5665         struct xfs_iext_cursor          *icur,
5666         struct xfs_bmbt_irec            *got,           /* extent to shift */
5667         struct xfs_bmbt_irec            *left,          /* preceding extent */
5668         struct xfs_btree_cur            *cur,
5669         int                             *logflags)      /* output */
5670 {
5671         struct xfs_ifork                *ifp = XFS_IFORK_PTR(ip, whichfork);
5672         struct xfs_bmbt_irec            new;
5673         xfs_filblks_t                   blockcount;
5674         int                             error, i;
5675         struct xfs_mount                *mp = ip->i_mount;
5676
5677         blockcount = left->br_blockcount + got->br_blockcount;
5678
5679         ASSERT(xfs_isilocked(ip, XFS_IOLOCK_EXCL));
5680         ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
5681         ASSERT(xfs_bmse_can_merge(left, got, shift));
5682
5683         new = *left;
5684         new.br_blockcount = blockcount;
5685
5686         /*
5687          * Update the on-disk extent count, the btree if necessary and log the
5688          * inode.
5689          */
5690         ifp->if_nextents--;
5691         *logflags |= XFS_ILOG_CORE;
5692         if (!cur) {
5693                 *logflags |= XFS_ILOG_DEXT;
5694                 goto done;
5695         }
5696
5697         /* lookup and remove the extent to merge */
5698         error = xfs_bmbt_lookup_eq(cur, got, &i);
5699         if (error)
5700                 return error;
5701         if (XFS_IS_CORRUPT(mp, i != 1))
5702                 return -EFSCORRUPTED;
5703
5704         error = xfs_btree_delete(cur, &i);
5705         if (error)
5706                 return error;
5707         if (XFS_IS_CORRUPT(mp, i != 1))
5708                 return -EFSCORRUPTED;
5709
5710         /* lookup and update size of the previous extent */
5711         error = xfs_bmbt_lookup_eq(cur, left, &i);
5712         if (error)
5713                 return error;
5714         if (XFS_IS_CORRUPT(mp, i != 1))
5715                 return -EFSCORRUPTED;
5716
5717         error = xfs_bmbt_update(cur, &new);
5718         if (error)
5719                 return error;
5720
5721         /* change to extent format if required after extent removal */
5722         error = xfs_bmap_btree_to_extents(tp, ip, cur, logflags, whichfork);
5723         if (error)
5724                 return error;
5725
5726 done:
5727         xfs_iext_remove(ip, icur, 0);
5728         xfs_iext_prev(ifp, icur);
5729         xfs_iext_update_extent(ip, xfs_bmap_fork_to_state(whichfork), icur,
5730                         &new);
5731
5732         /* update reverse mapping. rmap functions merge the rmaps for us */
5733         xfs_rmap_unmap_extent(tp, ip, whichfork, got);
5734         memcpy(&new, got, sizeof(new));
5735         new.br_startoff = left->br_startoff + left->br_blockcount;
5736         xfs_rmap_map_extent(tp, ip, whichfork, &new);
5737         return 0;
5738 }
5739
5740 static int
5741 xfs_bmap_shift_update_extent(
5742         struct xfs_trans        *tp,
5743         struct xfs_inode        *ip,
5744         int                     whichfork,
5745         struct xfs_iext_cursor  *icur,
5746         struct xfs_bmbt_irec    *got,
5747         struct xfs_btree_cur    *cur,
5748         int                     *logflags,
5749         xfs_fileoff_t           startoff)
5750 {
5751         struct xfs_mount        *mp = ip->i_mount;
5752         struct xfs_bmbt_irec    prev = *got;
5753         int                     error, i;
5754
5755         *logflags |= XFS_ILOG_CORE;
5756
5757         got->br_startoff = startoff;
5758
5759         if (cur) {
5760                 error = xfs_bmbt_lookup_eq(cur, &prev, &i);
5761                 if (error)
5762                         return error;
5763                 if (XFS_IS_CORRUPT(mp, i != 1))
5764                         return -EFSCORRUPTED;
5765
5766                 error = xfs_bmbt_update(cur, got);
5767                 if (error)
5768                         return error;
5769         } else {
5770                 *logflags |= XFS_ILOG_DEXT;
5771         }
5772
5773         xfs_iext_update_extent(ip, xfs_bmap_fork_to_state(whichfork), icur,
5774                         got);
5775
5776         /* update reverse mapping */
5777         xfs_rmap_unmap_extent(tp, ip, whichfork, &prev);
5778         xfs_rmap_map_extent(tp, ip, whichfork, got);
5779         return 0;
5780 }
5781
5782 int
5783 xfs_bmap_collapse_extents(
5784         struct xfs_trans        *tp,
5785         struct xfs_inode        *ip,
5786         xfs_fileoff_t           *next_fsb,
5787         xfs_fileoff_t           offset_shift_fsb,
5788         bool                    *done)
5789 {
5790         int                     whichfork = XFS_DATA_FORK;
5791         struct xfs_mount        *mp = ip->i_mount;
5792         struct xfs_ifork        *ifp = XFS_IFORK_PTR(ip, whichfork);
5793         struct xfs_btree_cur    *cur = NULL;
5794         struct xfs_bmbt_irec    got, prev;
5795         struct xfs_iext_cursor  icur;
5796         xfs_fileoff_t           new_startoff;
5797         int                     error = 0;
5798         int                     logflags = 0;
5799
5800         if (XFS_IS_CORRUPT(mp, !xfs_ifork_has_extents(ifp)) ||
5801             XFS_TEST_ERROR(false, mp, XFS_ERRTAG_BMAPIFORMAT)) {
5802                 return -EFSCORRUPTED;
5803         }
5804
5805         if (xfs_is_shutdown(mp))
5806                 return -EIO;
5807
5808         ASSERT(xfs_isilocked(ip, XFS_IOLOCK_EXCL | XFS_ILOCK_EXCL));
5809
5810         error = xfs_iread_extents(tp, ip, whichfork);
5811         if (error)
5812                 return error;
5813
5814         if (ifp->if_format == XFS_DINODE_FMT_BTREE) {
5815                 cur = xfs_bmbt_init_cursor(mp, tp, ip, whichfork);
5816                 cur->bc_ino.flags = 0;
5817         }
5818
5819         if (!xfs_iext_lookup_extent(ip, ifp, *next_fsb, &icur, &got)) {
5820                 *done = true;
5821                 goto del_cursor;
5822         }
5823         if (XFS_IS_CORRUPT(mp, isnullstartblock(got.br_startblock))) {
5824                 error = -EFSCORRUPTED;
5825                 goto del_cursor;
5826         }
5827
5828         new_startoff = got.br_startoff - offset_shift_fsb;
5829         if (xfs_iext_peek_prev_extent(ifp, &icur, &prev)) {
5830                 if (new_startoff < prev.br_startoff + prev.br_blockcount) {
5831                         error = -EINVAL;
5832                         goto del_cursor;
5833                 }
5834
5835                 if (xfs_bmse_can_merge(&prev, &got, offset_shift_fsb)) {
5836                         error = xfs_bmse_merge(tp, ip, whichfork,
5837                                         offset_shift_fsb, &icur, &got, &prev,
5838                                         cur, &logflags);
5839                         if (error)
5840                                 goto del_cursor;
5841                         goto done;
5842                 }
5843         } else {
5844                 if (got.br_startoff < offset_shift_fsb) {
5845                         error = -EINVAL;
5846                         goto del_cursor;
5847                 }
5848         }
5849
5850         error = xfs_bmap_shift_update_extent(tp, ip, whichfork, &icur, &got,
5851                         cur, &logflags, new_startoff);
5852         if (error)
5853                 goto del_cursor;
5854
5855 done:
5856         if (!xfs_iext_next_extent(ifp, &icur, &got)) {
5857                 *done = true;
5858                 goto del_cursor;
5859         }
5860
5861         *next_fsb = got.br_startoff;
5862 del_cursor:
5863         if (cur)
5864                 xfs_btree_del_cursor(cur, error);
5865         if (logflags)
5866                 xfs_trans_log_inode(tp, ip, logflags);
5867         return error;
5868 }
5869
5870 /* Make sure we won't be right-shifting an extent past the maximum bound. */
5871 int
5872 xfs_bmap_can_insert_extents(
5873         struct xfs_inode        *ip,
5874         xfs_fileoff_t           off,
5875         xfs_fileoff_t           shift)
5876 {
5877         struct xfs_bmbt_irec    got;
5878         int                     is_empty;
5879         int                     error = 0;
5880
5881         ASSERT(xfs_isilocked(ip, XFS_IOLOCK_EXCL));
5882
5883         if (xfs_is_shutdown(ip->i_mount))
5884                 return -EIO;
5885
5886         xfs_ilock(ip, XFS_ILOCK_EXCL);
5887         error = xfs_bmap_last_extent(NULL, ip, XFS_DATA_FORK, &got, &is_empty);
5888         if (!error && !is_empty && got.br_startoff >= off &&
5889             ((got.br_startoff + shift) & BMBT_STARTOFF_MASK) < got.br_startoff)
5890                 error = -EINVAL;
5891         xfs_iunlock(ip, XFS_ILOCK_EXCL);
5892
5893         return error;
5894 }
5895
5896 int
5897 xfs_bmap_insert_extents(
5898         struct xfs_trans        *tp,
5899         struct xfs_inode        *ip,
5900         xfs_fileoff_t           *next_fsb,
5901         xfs_fileoff_t           offset_shift_fsb,
5902         bool                    *done,
5903         xfs_fileoff_t           stop_fsb)
5904 {
5905         int                     whichfork = XFS_DATA_FORK;
5906         struct xfs_mount        *mp = ip->i_mount;
5907         struct xfs_ifork        *ifp = XFS_IFORK_PTR(ip, whichfork);
5908         struct xfs_btree_cur    *cur = NULL;
5909         struct xfs_bmbt_irec    got, next;
5910         struct xfs_iext_cursor  icur;
5911         xfs_fileoff_t           new_startoff;
5912         int                     error = 0;
5913         int                     logflags = 0;
5914
5915         if (XFS_IS_CORRUPT(mp, !xfs_ifork_has_extents(ifp)) ||
5916             XFS_TEST_ERROR(false, mp, XFS_ERRTAG_BMAPIFORMAT)) {
5917                 return -EFSCORRUPTED;
5918         }
5919
5920         if (xfs_is_shutdown(mp))
5921                 return -EIO;
5922
5923         ASSERT(xfs_isilocked(ip, XFS_IOLOCK_EXCL | XFS_ILOCK_EXCL));
5924
5925         error = xfs_iread_extents(tp, ip, whichfork);
5926         if (error)
5927                 return error;
5928
5929         if (ifp->if_format == XFS_DINODE_FMT_BTREE) {
5930                 cur = xfs_bmbt_init_cursor(mp, tp, ip, whichfork);
5931                 cur->bc_ino.flags = 0;
5932         }
5933
5934         if (*next_fsb == NULLFSBLOCK) {
5935                 xfs_iext_last(ifp, &icur);
5936                 if (!xfs_iext_get_extent(ifp, &icur, &got) ||
5937                     stop_fsb > got.br_startoff) {
5938                         *done = true;
5939                         goto del_cursor;
5940                 }
5941         } else {
5942                 if (!xfs_iext_lookup_extent(ip, ifp, *next_fsb, &icur, &got)) {
5943                         *done = true;
5944                         goto del_cursor;
5945                 }
5946         }
5947         if (XFS_IS_CORRUPT(mp, isnullstartblock(got.br_startblock))) {
5948                 error = -EFSCORRUPTED;
5949                 goto del_cursor;
5950         }
5951
5952         if (XFS_IS_CORRUPT(mp, stop_fsb > got.br_startoff)) {
5953                 error = -EFSCORRUPTED;
5954                 goto del_cursor;
5955         }
5956
5957         new_startoff = got.br_startoff + offset_shift_fsb;
5958         if (xfs_iext_peek_next_extent(ifp, &icur, &next)) {
5959                 if (new_startoff + got.br_blockcount > next.br_startoff) {
5960                         error = -EINVAL;
5961                         goto del_cursor;
5962                 }
5963
5964                 /*
5965                  * Unlike a left shift (which involves a hole punch), a right
5966                  * shift does not modify extent neighbors in any way.  We should
5967                  * never find mergeable extents in this scenario.  Check anyways
5968                  * and warn if we encounter two extents that could be one.
5969                  */
5970                 if (xfs_bmse_can_merge(&got, &next, offset_shift_fsb))
5971                         WARN_ON_ONCE(1);
5972         }
5973
5974         error = xfs_bmap_shift_update_extent(tp, ip, whichfork, &icur, &got,
5975                         cur, &logflags, new_startoff);
5976         if (error)
5977                 goto del_cursor;
5978
5979         if (!xfs_iext_prev_extent(ifp, &icur, &got) ||
5980             stop_fsb >= got.br_startoff + got.br_blockcount) {
5981                 *done = true;
5982                 goto del_cursor;
5983         }
5984
5985         *next_fsb = got.br_startoff;
5986 del_cursor:
5987         if (cur)
5988                 xfs_btree_del_cursor(cur, error);
5989         if (logflags)
5990                 xfs_trans_log_inode(tp, ip, logflags);
5991         return error;
5992 }
5993
5994 /*
5995  * Splits an extent into two extents at split_fsb block such that it is the
5996  * first block of the current_ext. @ext is a target extent to be split.
5997  * @split_fsb is a block where the extents is split.  If split_fsb lies in a
5998  * hole or the first block of extents, just return 0.
5999  */
6000 int
6001 xfs_bmap_split_extent(
6002         struct xfs_trans        *tp,
6003         struct xfs_inode        *ip,
6004         xfs_fileoff_t           split_fsb)
6005 {
6006         int                             whichfork = XFS_DATA_FORK;
6007         struct xfs_ifork                *ifp = XFS_IFORK_PTR(ip, whichfork);
6008         struct xfs_btree_cur            *cur = NULL;
6009         struct xfs_bmbt_irec            got;
6010         struct xfs_bmbt_irec            new; /* split extent */
6011         struct xfs_mount                *mp = ip->i_mount;
6012         xfs_fsblock_t                   gotblkcnt; /* new block count for got */
6013         struct xfs_iext_cursor          icur;
6014         int                             error = 0;
6015         int                             logflags = 0;
6016         int                             i = 0;
6017
6018         if (XFS_IS_CORRUPT(mp, !xfs_ifork_has_extents(ifp)) ||
6019             XFS_TEST_ERROR(false, mp, XFS_ERRTAG_BMAPIFORMAT)) {
6020                 return -EFSCORRUPTED;
6021         }
6022
6023         if (xfs_is_shutdown(mp))
6024                 return -EIO;
6025
6026         /* Read in all the extents */
6027         error = xfs_iread_extents(tp, ip, whichfork);
6028         if (error)
6029                 return error;
6030
6031         /*
6032          * If there are not extents, or split_fsb lies in a hole we are done.
6033          */
6034         if (!xfs_iext_lookup_extent(ip, ifp, split_fsb, &icur, &got) ||
6035             got.br_startoff >= split_fsb)
6036                 return 0;
6037
6038         gotblkcnt = split_fsb - got.br_startoff;
6039         new.br_startoff = split_fsb;
6040         new.br_startblock = got.br_startblock + gotblkcnt;
6041         new.br_blockcount = got.br_blockcount - gotblkcnt;
6042         new.br_state = got.br_state;
6043
6044         if (ifp->if_format == XFS_DINODE_FMT_BTREE) {
6045                 cur = xfs_bmbt_init_cursor(mp, tp, ip, whichfork);
6046                 cur->bc_ino.flags = 0;
6047                 error = xfs_bmbt_lookup_eq(cur, &got, &i);
6048                 if (error)
6049                         goto del_cursor;
6050                 if (XFS_IS_CORRUPT(mp, i != 1)) {
6051                         error = -EFSCORRUPTED;
6052                         goto del_cursor;
6053                 }
6054         }
6055
6056         got.br_blockcount = gotblkcnt;
6057         xfs_iext_update_extent(ip, xfs_bmap_fork_to_state(whichfork), &icur,
6058                         &got);
6059
6060         logflags = XFS_ILOG_CORE;
6061         if (cur) {
6062                 error = xfs_bmbt_update(cur, &got);
6063                 if (error)
6064                         goto del_cursor;
6065         } else
6066                 logflags |= XFS_ILOG_DEXT;
6067
6068         /* Add new extent */
6069         xfs_iext_next(ifp, &icur);
6070         xfs_iext_insert(ip, &icur, &new, 0);
6071         ifp->if_nextents++;
6072
6073         if (cur) {
6074                 error = xfs_bmbt_lookup_eq(cur, &new, &i);
6075                 if (error)
6076                         goto del_cursor;
6077                 if (XFS_IS_CORRUPT(mp, i != 0)) {
6078                         error = -EFSCORRUPTED;
6079                         goto del_cursor;
6080                 }
6081                 error = xfs_btree_insert(cur, &i);
6082                 if (error)
6083                         goto del_cursor;
6084                 if (XFS_IS_CORRUPT(mp, i != 1)) {
6085                         error = -EFSCORRUPTED;
6086                         goto del_cursor;
6087                 }
6088         }
6089
6090         /*
6091          * Convert to a btree if necessary.
6092          */
6093         if (xfs_bmap_needs_btree(ip, whichfork)) {
6094                 int tmp_logflags; /* partial log flag return val */
6095
6096                 ASSERT(cur == NULL);
6097                 error = xfs_bmap_extents_to_btree(tp, ip, &cur, 0,
6098                                 &tmp_logflags, whichfork);
6099                 logflags |= tmp_logflags;
6100         }
6101
6102 del_cursor:
6103         if (cur) {
6104                 cur->bc_ino.allocated = 0;
6105                 xfs_btree_del_cursor(cur, error);
6106         }
6107
6108         if (logflags)
6109                 xfs_trans_log_inode(tp, ip, logflags);
6110         return error;
6111 }
6112
6113 /* Deferred mapping is only for real extents in the data fork. */
6114 static bool
6115 xfs_bmap_is_update_needed(
6116         struct xfs_bmbt_irec    *bmap)
6117 {
6118         return  bmap->br_startblock != HOLESTARTBLOCK &&
6119                 bmap->br_startblock != DELAYSTARTBLOCK;
6120 }
6121
6122 /* Record a bmap intent. */
6123 static int
6124 __xfs_bmap_add(
6125         struct xfs_trans                *tp,
6126         enum xfs_bmap_intent_type       type,
6127         struct xfs_inode                *ip,
6128         int                             whichfork,
6129         struct xfs_bmbt_irec            *bmap)
6130 {
6131         struct xfs_bmap_intent          *bi;
6132
6133         trace_xfs_bmap_defer(tp->t_mountp,
6134                         XFS_FSB_TO_AGNO(tp->t_mountp, bmap->br_startblock),
6135                         type,
6136                         XFS_FSB_TO_AGBNO(tp->t_mountp, bmap->br_startblock),
6137                         ip->i_ino, whichfork,
6138                         bmap->br_startoff,
6139                         bmap->br_blockcount,
6140                         bmap->br_state);
6141
6142         bi = kmem_cache_alloc(xfs_bmap_intent_cache, GFP_NOFS | __GFP_NOFAIL);
6143         INIT_LIST_HEAD(&bi->bi_list);
6144         bi->bi_type = type;
6145         bi->bi_owner = ip;
6146         bi->bi_whichfork = whichfork;
6147         bi->bi_bmap = *bmap;
6148
6149         xfs_defer_add(tp, XFS_DEFER_OPS_TYPE_BMAP, &bi->bi_list);
6150         return 0;
6151 }
6152
6153 /* Map an extent into a file. */
6154 void
6155 xfs_bmap_map_extent(
6156         struct xfs_trans        *tp,
6157         struct xfs_inode        *ip,
6158         struct xfs_bmbt_irec    *PREV)
6159 {
6160         if (!xfs_bmap_is_update_needed(PREV))
6161                 return;
6162
6163         __xfs_bmap_add(tp, XFS_BMAP_MAP, ip, XFS_DATA_FORK, PREV);
6164 }
6165
6166 /* Unmap an extent out of a file. */
6167 void
6168 xfs_bmap_unmap_extent(
6169         struct xfs_trans        *tp,
6170         struct xfs_inode        *ip,
6171         struct xfs_bmbt_irec    *PREV)
6172 {
6173         if (!xfs_bmap_is_update_needed(PREV))
6174                 return;
6175
6176         __xfs_bmap_add(tp, XFS_BMAP_UNMAP, ip, XFS_DATA_FORK, PREV);
6177 }
6178
6179 /*
6180  * Process one of the deferred bmap operations.  We pass back the
6181  * btree cursor to maintain our lock on the bmapbt between calls.
6182  */
6183 int
6184 xfs_bmap_finish_one(
6185         struct xfs_trans                *tp,
6186         struct xfs_inode                *ip,
6187         enum xfs_bmap_intent_type       type,
6188         int                             whichfork,
6189         xfs_fileoff_t                   startoff,
6190         xfs_fsblock_t                   startblock,
6191         xfs_filblks_t                   *blockcount,
6192         xfs_exntst_t                    state)
6193 {
6194         int                             error = 0;
6195
6196         ASSERT(tp->t_firstblock == NULLFSBLOCK);
6197
6198         trace_xfs_bmap_deferred(tp->t_mountp,
6199                         XFS_FSB_TO_AGNO(tp->t_mountp, startblock), type,
6200                         XFS_FSB_TO_AGBNO(tp->t_mountp, startblock),
6201                         ip->i_ino, whichfork, startoff, *blockcount, state);
6202
6203         if (WARN_ON_ONCE(whichfork != XFS_DATA_FORK))
6204                 return -EFSCORRUPTED;
6205
6206         if (XFS_TEST_ERROR(false, tp->t_mountp,
6207                         XFS_ERRTAG_BMAP_FINISH_ONE))
6208                 return -EIO;
6209
6210         switch (type) {
6211         case XFS_BMAP_MAP:
6212                 error = xfs_bmapi_remap(tp, ip, startoff, *blockcount,
6213                                 startblock, 0);
6214                 *blockcount = 0;
6215                 break;
6216         case XFS_BMAP_UNMAP:
6217                 error = __xfs_bunmapi(tp, ip, startoff, blockcount,
6218                                 XFS_BMAPI_REMAP, 1);
6219                 break;
6220         default:
6221                 ASSERT(0);
6222                 error = -EFSCORRUPTED;
6223         }
6224
6225         return error;
6226 }
6227
6228 /* Check that an inode's extent does not have invalid flags or bad ranges. */
6229 xfs_failaddr_t
6230 xfs_bmap_validate_extent(
6231         struct xfs_inode        *ip,
6232         int                     whichfork,
6233         struct xfs_bmbt_irec    *irec)
6234 {
6235         struct xfs_mount        *mp = ip->i_mount;
6236
6237         if (!xfs_verify_fileext(mp, irec->br_startoff, irec->br_blockcount))
6238                 return __this_address;
6239
6240         if (XFS_IS_REALTIME_INODE(ip) && whichfork == XFS_DATA_FORK) {
6241                 if (!xfs_verify_rtext(mp, irec->br_startblock,
6242                                           irec->br_blockcount))
6243                         return __this_address;
6244         } else {
6245                 if (!xfs_verify_fsbext(mp, irec->br_startblock,
6246                                            irec->br_blockcount))
6247                         return __this_address;
6248         }
6249         if (irec->br_state != XFS_EXT_NORM && whichfork != XFS_DATA_FORK)
6250                 return __this_address;
6251         return NULL;
6252 }
6253
6254 int __init
6255 xfs_bmap_intent_init_cache(void)
6256 {
6257         xfs_bmap_intent_cache = kmem_cache_create("xfs_bmap_intent",
6258                         sizeof(struct xfs_bmap_intent),
6259                         0, 0, NULL);
6260
6261         return xfs_bmap_intent_cache != NULL ? 0 : -ENOMEM;
6262 }
6263
6264 void
6265 xfs_bmap_intent_destroy_cache(void)
6266 {
6267         kmem_cache_destroy(xfs_bmap_intent_cache);
6268         xfs_bmap_intent_cache = NULL;
6269 }