1 /* 2 * Copyright (c) 2000-2006 Silicon Graphics, Inc. 3 * All Rights Reserved. 4 * 5 * This program is free software; you can redistribute it and/or 6 * modify it under the terms of the GNU General Public License as 7 * published by the Free Software Foundation. 8 * 9 * This program is distributed in the hope that it would be useful, 10 * but WITHOUT ANY WARRANTY; without even the implied warranty of 11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 12 * GNU General Public License for more details. 13 * 14 * You should have received a copy of the GNU General Public License 15 * along with this program; if not, write the Free Software Foundation, 16 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA 17 */ 18 #include "xfs.h" 19 #include "xfs_fs.h" 20 #include "xfs_bit.h" 21 #include "xfs_log.h" 22 #include "xfs_inum.h" 23 #include "xfs_trans.h" 24 #include "xfs_sb.h" 25 #include "xfs_ag.h" 26 #include "xfs_alloc.h" 27 #include "xfs_quota.h" 28 #include "xfs_mount.h" 29 #include "xfs_bmap_btree.h" 30 #include "xfs_alloc_btree.h" 31 #include "xfs_ialloc_btree.h" 32 #include "xfs_dinode.h" 33 #include "xfs_inode.h" 34 #include "xfs_btree.h" 35 #include "xfs_bmap.h" 36 #include "xfs_rtalloc.h" 37 #include "xfs_error.h" 38 #include "xfs_itable.h" 39 #include "xfs_rw.h" 40 #include "xfs_attr.h" 41 #include "xfs_buf_item.h" 42 #include "xfs_trans_space.h" 43 #include "xfs_utils.h" 44 #include "xfs_iomap.h" 45 #include "xfs_trace.h" 46 47 48 #define XFS_WRITEIO_ALIGN(mp,off) (((off) >> mp->m_writeio_log) \ 49 << mp->m_writeio_log) 50 #define XFS_WRITE_IMAPS XFS_BMAP_MAX_NMAP 51 52 STATIC int 53 xfs_iomap_eof_align_last_fsb( 54 xfs_mount_t *mp, 55 xfs_inode_t *ip, 56 xfs_extlen_t extsize, 57 xfs_fileoff_t *last_fsb) 58 { 59 xfs_fileoff_t new_last_fsb = 0; 60 xfs_extlen_t align; 61 int eof, error; 62 63 if (XFS_IS_REALTIME_INODE(ip)) 64 ; 65 /* 66 * If mounted with the "-o swalloc" option, roundup the allocation 67 * request to a stripe width boundary if the file size is >= 68 * stripe width and we are allocating past the allocation eof. 69 */ 70 else if (mp->m_swidth && (mp->m_flags & XFS_MOUNT_SWALLOC) && 71 (ip->i_size >= XFS_FSB_TO_B(mp, mp->m_swidth))) 72 new_last_fsb = roundup_64(*last_fsb, mp->m_swidth); 73 /* 74 * Roundup the allocation request to a stripe unit (m_dalign) boundary 75 * if the file size is >= stripe unit size, and we are allocating past 76 * the allocation eof. 77 */ 78 else if (mp->m_dalign && (ip->i_size >= XFS_FSB_TO_B(mp, mp->m_dalign))) 79 new_last_fsb = roundup_64(*last_fsb, mp->m_dalign); 80 81 /* 82 * Always round up the allocation request to an extent boundary 83 * (when file on a real-time subvolume or has di_extsize hint). 84 */ 85 if (extsize) { 86 if (new_last_fsb) 87 align = roundup_64(new_last_fsb, extsize); 88 else 89 align = extsize; 90 new_last_fsb = roundup_64(*last_fsb, align); 91 } 92 93 if (new_last_fsb) { 94 error = xfs_bmap_eof(ip, new_last_fsb, XFS_DATA_FORK, &eof); 95 if (error) 96 return error; 97 if (eof) 98 *last_fsb = new_last_fsb; 99 } 100 return 0; 101 } 102 103 STATIC int 104 xfs_alert_fsblock_zero( 105 xfs_inode_t *ip, 106 xfs_bmbt_irec_t *imap) 107 { 108 xfs_alert_tag(ip->i_mount, XFS_PTAG_FSBLOCK_ZERO, 109 "Access to block zero in inode %llu " 110 "start_block: %llx start_off: %llx " 111 "blkcnt: %llx extent-state: %x\n", 112 (unsigned long long)ip->i_ino, 113 (unsigned long long)imap->br_startblock, 114 (unsigned long long)imap->br_startoff, 115 (unsigned long long)imap->br_blockcount, 116 imap->br_state); 117 return EFSCORRUPTED; 118 } 119 120 int 121 xfs_iomap_write_direct( 122 xfs_inode_t *ip, 123 xfs_off_t offset, 124 size_t count, 125 xfs_bmbt_irec_t *imap, 126 int nmaps) 127 { 128 xfs_mount_t *mp = ip->i_mount; 129 xfs_fileoff_t offset_fsb; 130 xfs_fileoff_t last_fsb; 131 xfs_filblks_t count_fsb, resaligned; 132 xfs_fsblock_t firstfsb; 133 xfs_extlen_t extsz, temp; 134 int nimaps; 135 int bmapi_flag; 136 int quota_flag; 137 int rt; 138 xfs_trans_t *tp; 139 xfs_bmap_free_t free_list; 140 uint qblocks, resblks, resrtextents; 141 int committed; 142 int error; 143 144 /* 145 * Make sure that the dquots are there. This doesn't hold 146 * the ilock across a disk read. 147 */ 148 error = xfs_qm_dqattach_locked(ip, 0); 149 if (error) 150 return XFS_ERROR(error); 151 152 rt = XFS_IS_REALTIME_INODE(ip); 153 extsz = xfs_get_extsz_hint(ip); 154 155 offset_fsb = XFS_B_TO_FSBT(mp, offset); 156 last_fsb = XFS_B_TO_FSB(mp, ((xfs_ufsize_t)(offset + count))); 157 if ((offset + count) > ip->i_size) { 158 error = xfs_iomap_eof_align_last_fsb(mp, ip, extsz, &last_fsb); 159 if (error) 160 goto error_out; 161 } else { 162 if (nmaps && (imap->br_startblock == HOLESTARTBLOCK)) 163 last_fsb = MIN(last_fsb, (xfs_fileoff_t) 164 imap->br_blockcount + 165 imap->br_startoff); 166 } 167 count_fsb = last_fsb - offset_fsb; 168 ASSERT(count_fsb > 0); 169 170 resaligned = count_fsb; 171 if (unlikely(extsz)) { 172 if ((temp = do_mod(offset_fsb, extsz))) 173 resaligned += temp; 174 if ((temp = do_mod(resaligned, extsz))) 175 resaligned += extsz - temp; 176 } 177 178 if (unlikely(rt)) { 179 resrtextents = qblocks = resaligned; 180 resrtextents /= mp->m_sb.sb_rextsize; 181 resblks = XFS_DIOSTRAT_SPACE_RES(mp, 0); 182 quota_flag = XFS_QMOPT_RES_RTBLKS; 183 } else { 184 resrtextents = 0; 185 resblks = qblocks = XFS_DIOSTRAT_SPACE_RES(mp, resaligned); 186 quota_flag = XFS_QMOPT_RES_REGBLKS; 187 } 188 189 /* 190 * Allocate and setup the transaction 191 */ 192 xfs_iunlock(ip, XFS_ILOCK_EXCL); 193 tp = xfs_trans_alloc(mp, XFS_TRANS_DIOSTRAT); 194 error = xfs_trans_reserve(tp, resblks, 195 XFS_WRITE_LOG_RES(mp), resrtextents, 196 XFS_TRANS_PERM_LOG_RES, 197 XFS_WRITE_LOG_COUNT); 198 /* 199 * Check for running out of space, note: need lock to return 200 */ 201 if (error) 202 xfs_trans_cancel(tp, 0); 203 xfs_ilock(ip, XFS_ILOCK_EXCL); 204 if (error) 205 goto error_out; 206 207 error = xfs_trans_reserve_quota_nblks(tp, ip, qblocks, 0, quota_flag); 208 if (error) 209 goto error1; 210 211 xfs_trans_ijoin(tp, ip, 0); 212 213 bmapi_flag = 0; 214 if (offset < ip->i_size || extsz) 215 bmapi_flag |= XFS_BMAPI_PREALLOC; 216 217 /* 218 * From this point onwards we overwrite the imap pointer that the 219 * caller gave to us. 220 */ 221 xfs_bmap_init(&free_list, &firstfsb); 222 nimaps = 1; 223 error = xfs_bmapi_write(tp, ip, offset_fsb, count_fsb, bmapi_flag, 224 &firstfsb, 0, imap, &nimaps, &free_list); 225 if (error) 226 goto error0; 227 228 /* 229 * Complete the transaction 230 */ 231 error = xfs_bmap_finish(&tp, &free_list, &committed); 232 if (error) 233 goto error0; 234 error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES); 235 if (error) 236 goto error_out; 237 238 /* 239 * Copy any maps to caller's array and return any error. 240 */ 241 if (nimaps == 0) { 242 error = ENOSPC; 243 goto error_out; 244 } 245 246 if (!(imap->br_startblock || XFS_IS_REALTIME_INODE(ip))) { 247 error = xfs_alert_fsblock_zero(ip, imap); 248 goto error_out; 249 } 250 251 return 0; 252 253 error0: /* Cancel bmap, unlock inode, unreserve quota blocks, cancel trans */ 254 xfs_bmap_cancel(&free_list); 255 xfs_trans_unreserve_quota_nblks(tp, ip, qblocks, 0, quota_flag); 256 257 error1: /* Just cancel transaction */ 258 xfs_trans_cancel(tp, XFS_TRANS_RELEASE_LOG_RES | XFS_TRANS_ABORT); 259 260 error_out: 261 return XFS_ERROR(error); 262 } 263 264 /* 265 * If the caller is doing a write at the end of the file, then extend the 266 * allocation out to the file system's write iosize. We clean up any extra 267 * space left over when the file is closed in xfs_inactive(). 268 * 269 * If we find we already have delalloc preallocation beyond EOF, don't do more 270 * preallocation as it it not needed. 271 */ 272 STATIC int 273 xfs_iomap_eof_want_preallocate( 274 xfs_mount_t *mp, 275 xfs_inode_t *ip, 276 xfs_off_t offset, 277 size_t count, 278 xfs_bmbt_irec_t *imap, 279 int nimaps, 280 int *prealloc) 281 { 282 xfs_fileoff_t start_fsb; 283 xfs_filblks_t count_fsb; 284 xfs_fsblock_t firstblock; 285 int n, error, imaps; 286 int found_delalloc = 0; 287 288 *prealloc = 0; 289 if ((offset + count) <= ip->i_size) 290 return 0; 291 292 /* 293 * If there are any real blocks past eof, then don't 294 * do any speculative allocation. 295 */ 296 start_fsb = XFS_B_TO_FSBT(mp, ((xfs_ufsize_t)(offset + count - 1))); 297 count_fsb = XFS_B_TO_FSB(mp, (xfs_ufsize_t)XFS_MAXIOFFSET(mp)); 298 while (count_fsb > 0) { 299 imaps = nimaps; 300 firstblock = NULLFSBLOCK; 301 error = xfs_bmapi_read(ip, start_fsb, count_fsb, imap, &imaps, 302 0); 303 if (error) 304 return error; 305 for (n = 0; n < imaps; n++) { 306 if ((imap[n].br_startblock != HOLESTARTBLOCK) && 307 (imap[n].br_startblock != DELAYSTARTBLOCK)) 308 return 0; 309 start_fsb += imap[n].br_blockcount; 310 count_fsb -= imap[n].br_blockcount; 311 312 if (imap[n].br_startblock == DELAYSTARTBLOCK) 313 found_delalloc = 1; 314 } 315 } 316 if (!found_delalloc) 317 *prealloc = 1; 318 return 0; 319 } 320 321 /* 322 * If we don't have a user specified preallocation size, dynamically increase 323 * the preallocation size as the size of the file grows. Cap the maximum size 324 * at a single extent or less if the filesystem is near full. The closer the 325 * filesystem is to full, the smaller the maximum prealocation. 326 */ 327 STATIC xfs_fsblock_t 328 xfs_iomap_prealloc_size( 329 struct xfs_mount *mp, 330 struct xfs_inode *ip) 331 { 332 xfs_fsblock_t alloc_blocks = 0; 333 334 if (!(mp->m_flags & XFS_MOUNT_DFLT_IOSIZE)) { 335 int shift = 0; 336 int64_t freesp; 337 338 /* 339 * rounddown_pow_of_two() returns an undefined result 340 * if we pass in alloc_blocks = 0. Hence the "+ 1" to 341 * ensure we always pass in a non-zero value. 342 */ 343 alloc_blocks = XFS_B_TO_FSB(mp, ip->i_size) + 1; 344 alloc_blocks = XFS_FILEOFF_MIN(MAXEXTLEN, 345 rounddown_pow_of_two(alloc_blocks)); 346 347 xfs_icsb_sync_counters(mp, XFS_ICSB_LAZY_COUNT); 348 freesp = mp->m_sb.sb_fdblocks; 349 if (freesp < mp->m_low_space[XFS_LOWSP_5_PCNT]) { 350 shift = 2; 351 if (freesp < mp->m_low_space[XFS_LOWSP_4_PCNT]) 352 shift++; 353 if (freesp < mp->m_low_space[XFS_LOWSP_3_PCNT]) 354 shift++; 355 if (freesp < mp->m_low_space[XFS_LOWSP_2_PCNT]) 356 shift++; 357 if (freesp < mp->m_low_space[XFS_LOWSP_1_PCNT]) 358 shift++; 359 } 360 if (shift) 361 alloc_blocks >>= shift; 362 } 363 364 if (alloc_blocks < mp->m_writeio_blocks) 365 alloc_blocks = mp->m_writeio_blocks; 366 367 return alloc_blocks; 368 } 369 370 int 371 xfs_iomap_write_delay( 372 xfs_inode_t *ip, 373 xfs_off_t offset, 374 size_t count, 375 xfs_bmbt_irec_t *ret_imap) 376 { 377 xfs_mount_t *mp = ip->i_mount; 378 xfs_fileoff_t offset_fsb; 379 xfs_fileoff_t last_fsb; 380 xfs_off_t aligned_offset; 381 xfs_fileoff_t ioalign; 382 xfs_extlen_t extsz; 383 int nimaps; 384 xfs_bmbt_irec_t imap[XFS_WRITE_IMAPS]; 385 int prealloc, flushed = 0; 386 int error; 387 388 ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL)); 389 390 /* 391 * Make sure that the dquots are there. This doesn't hold 392 * the ilock across a disk read. 393 */ 394 error = xfs_qm_dqattach_locked(ip, 0); 395 if (error) 396 return XFS_ERROR(error); 397 398 extsz = xfs_get_extsz_hint(ip); 399 offset_fsb = XFS_B_TO_FSBT(mp, offset); 400 401 402 error = xfs_iomap_eof_want_preallocate(mp, ip, offset, count, 403 imap, XFS_WRITE_IMAPS, &prealloc); 404 if (error) 405 return error; 406 407 retry: 408 if (prealloc) { 409 xfs_fsblock_t alloc_blocks = xfs_iomap_prealloc_size(mp, ip); 410 411 aligned_offset = XFS_WRITEIO_ALIGN(mp, (offset + count - 1)); 412 ioalign = XFS_B_TO_FSBT(mp, aligned_offset); 413 last_fsb = ioalign + alloc_blocks; 414 } else { 415 last_fsb = XFS_B_TO_FSB(mp, ((xfs_ufsize_t)(offset + count))); 416 } 417 418 if (prealloc || extsz) { 419 error = xfs_iomap_eof_align_last_fsb(mp, ip, extsz, &last_fsb); 420 if (error) 421 return error; 422 } 423 424 nimaps = XFS_WRITE_IMAPS; 425 error = xfs_bmapi_delay(ip, offset_fsb, last_fsb - offset_fsb, 426 imap, &nimaps, XFS_BMAPI_ENTIRE); 427 switch (error) { 428 case 0: 429 case ENOSPC: 430 case EDQUOT: 431 break; 432 default: 433 return XFS_ERROR(error); 434 } 435 436 /* 437 * If bmapi returned us nothing, we got either ENOSPC or EDQUOT. For 438 * ENOSPC, * flush all other inodes with delalloc blocks to free up 439 * some of the excess reserved metadata space. For both cases, retry 440 * without EOF preallocation. 441 */ 442 if (nimaps == 0) { 443 trace_xfs_delalloc_enospc(ip, offset, count); 444 if (flushed) 445 return XFS_ERROR(error ? error : ENOSPC); 446 447 if (error == ENOSPC) { 448 xfs_iunlock(ip, XFS_ILOCK_EXCL); 449 xfs_flush_inodes(ip); 450 xfs_ilock(ip, XFS_ILOCK_EXCL); 451 } 452 453 flushed = 1; 454 error = 0; 455 prealloc = 0; 456 goto retry; 457 } 458 459 if (!(imap[0].br_startblock || XFS_IS_REALTIME_INODE(ip))) 460 return xfs_alert_fsblock_zero(ip, &imap[0]); 461 462 *ret_imap = imap[0]; 463 return 0; 464 } 465 466 /* 467 * Pass in a delayed allocate extent, convert it to real extents; 468 * return to the caller the extent we create which maps on top of 469 * the originating callers request. 470 * 471 * Called without a lock on the inode. 472 * 473 * We no longer bother to look at the incoming map - all we have to 474 * guarantee is that whatever we allocate fills the required range. 475 */ 476 int 477 xfs_iomap_write_allocate( 478 xfs_inode_t *ip, 479 xfs_off_t offset, 480 size_t count, 481 xfs_bmbt_irec_t *imap) 482 { 483 xfs_mount_t *mp = ip->i_mount; 484 xfs_fileoff_t offset_fsb, last_block; 485 xfs_fileoff_t end_fsb, map_start_fsb; 486 xfs_fsblock_t first_block; 487 xfs_bmap_free_t free_list; 488 xfs_filblks_t count_fsb; 489 xfs_trans_t *tp; 490 int nimaps, committed; 491 int error = 0; 492 int nres; 493 494 /* 495 * Make sure that the dquots are there. 496 */ 497 error = xfs_qm_dqattach(ip, 0); 498 if (error) 499 return XFS_ERROR(error); 500 501 offset_fsb = XFS_B_TO_FSBT(mp, offset); 502 count_fsb = imap->br_blockcount; 503 map_start_fsb = imap->br_startoff; 504 505 XFS_STATS_ADD(xs_xstrat_bytes, XFS_FSB_TO_B(mp, count_fsb)); 506 507 while (count_fsb != 0) { 508 /* 509 * Set up a transaction with which to allocate the 510 * backing store for the file. Do allocations in a 511 * loop until we get some space in the range we are 512 * interested in. The other space that might be allocated 513 * is in the delayed allocation extent on which we sit 514 * but before our buffer starts. 515 */ 516 517 nimaps = 0; 518 while (nimaps == 0) { 519 tp = xfs_trans_alloc(mp, XFS_TRANS_STRAT_WRITE); 520 tp->t_flags |= XFS_TRANS_RESERVE; 521 nres = XFS_EXTENTADD_SPACE_RES(mp, XFS_DATA_FORK); 522 error = xfs_trans_reserve(tp, nres, 523 XFS_WRITE_LOG_RES(mp), 524 0, XFS_TRANS_PERM_LOG_RES, 525 XFS_WRITE_LOG_COUNT); 526 if (error) { 527 xfs_trans_cancel(tp, 0); 528 return XFS_ERROR(error); 529 } 530 xfs_ilock(ip, XFS_ILOCK_EXCL); 531 xfs_trans_ijoin(tp, ip, 0); 532 533 xfs_bmap_init(&free_list, &first_block); 534 535 /* 536 * it is possible that the extents have changed since 537 * we did the read call as we dropped the ilock for a 538 * while. We have to be careful about truncates or hole 539 * punchs here - we are not allowed to allocate 540 * non-delalloc blocks here. 541 * 542 * The only protection against truncation is the pages 543 * for the range we are being asked to convert are 544 * locked and hence a truncate will block on them 545 * first. 546 * 547 * As a result, if we go beyond the range we really 548 * need and hit an delalloc extent boundary followed by 549 * a hole while we have excess blocks in the map, we 550 * will fill the hole incorrectly and overrun the 551 * transaction reservation. 552 * 553 * Using a single map prevents this as we are forced to 554 * check each map we look for overlap with the desired 555 * range and abort as soon as we find it. Also, given 556 * that we only return a single map, having one beyond 557 * what we can return is probably a bit silly. 558 * 559 * We also need to check that we don't go beyond EOF; 560 * this is a truncate optimisation as a truncate sets 561 * the new file size before block on the pages we 562 * currently have locked under writeback. Because they 563 * are about to be tossed, we don't need to write them 564 * back.... 565 */ 566 nimaps = 1; 567 end_fsb = XFS_B_TO_FSB(mp, ip->i_size); 568 error = xfs_bmap_last_offset(NULL, ip, &last_block, 569 XFS_DATA_FORK); 570 if (error) 571 goto trans_cancel; 572 573 last_block = XFS_FILEOFF_MAX(last_block, end_fsb); 574 if ((map_start_fsb + count_fsb) > last_block) { 575 count_fsb = last_block - map_start_fsb; 576 if (count_fsb == 0) { 577 error = EAGAIN; 578 goto trans_cancel; 579 } 580 } 581 582 /* 583 * From this point onwards we overwrite the imap 584 * pointer that the caller gave to us. 585 */ 586 error = xfs_bmapi_write(tp, ip, map_start_fsb, 587 count_fsb, 0, &first_block, 1, 588 imap, &nimaps, &free_list); 589 if (error) 590 goto trans_cancel; 591 592 error = xfs_bmap_finish(&tp, &free_list, &committed); 593 if (error) 594 goto trans_cancel; 595 596 error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES); 597 if (error) 598 goto error0; 599 600 xfs_iunlock(ip, XFS_ILOCK_EXCL); 601 } 602 603 /* 604 * See if we were able to allocate an extent that 605 * covers at least part of the callers request 606 */ 607 if (!(imap->br_startblock || XFS_IS_REALTIME_INODE(ip))) 608 return xfs_alert_fsblock_zero(ip, imap); 609 610 if ((offset_fsb >= imap->br_startoff) && 611 (offset_fsb < (imap->br_startoff + 612 imap->br_blockcount))) { 613 XFS_STATS_INC(xs_xstrat_quick); 614 return 0; 615 } 616 617 /* 618 * So far we have not mapped the requested part of the 619 * file, just surrounding data, try again. 620 */ 621 count_fsb -= imap->br_blockcount; 622 map_start_fsb = imap->br_startoff + imap->br_blockcount; 623 } 624 625 trans_cancel: 626 xfs_bmap_cancel(&free_list); 627 xfs_trans_cancel(tp, XFS_TRANS_RELEASE_LOG_RES | XFS_TRANS_ABORT); 628 error0: 629 xfs_iunlock(ip, XFS_ILOCK_EXCL); 630 return XFS_ERROR(error); 631 } 632 633 int 634 xfs_iomap_write_unwritten( 635 xfs_inode_t *ip, 636 xfs_off_t offset, 637 size_t count) 638 { 639 xfs_mount_t *mp = ip->i_mount; 640 xfs_fileoff_t offset_fsb; 641 xfs_filblks_t count_fsb; 642 xfs_filblks_t numblks_fsb; 643 xfs_fsblock_t firstfsb; 644 int nimaps; 645 xfs_trans_t *tp; 646 xfs_bmbt_irec_t imap; 647 xfs_bmap_free_t free_list; 648 uint resblks; 649 int committed; 650 int error; 651 652 trace_xfs_unwritten_convert(ip, offset, count); 653 654 offset_fsb = XFS_B_TO_FSBT(mp, offset); 655 count_fsb = XFS_B_TO_FSB(mp, (xfs_ufsize_t)offset + count); 656 count_fsb = (xfs_filblks_t)(count_fsb - offset_fsb); 657 658 /* 659 * Reserve enough blocks in this transaction for two complete extent 660 * btree splits. We may be converting the middle part of an unwritten 661 * extent and in this case we will insert two new extents in the btree 662 * each of which could cause a full split. 663 * 664 * This reservation amount will be used in the first call to 665 * xfs_bmbt_split() to select an AG with enough space to satisfy the 666 * rest of the operation. 667 */ 668 resblks = XFS_DIOSTRAT_SPACE_RES(mp, 0) << 1; 669 670 do { 671 /* 672 * set up a transaction to convert the range of extents 673 * from unwritten to real. Do allocations in a loop until 674 * we have covered the range passed in. 675 * 676 * Note that we open code the transaction allocation here 677 * to pass KM_NOFS--we can't risk to recursing back into 678 * the filesystem here as we might be asked to write out 679 * the same inode that we complete here and might deadlock 680 * on the iolock. 681 */ 682 xfs_wait_for_freeze(mp, SB_FREEZE_TRANS); 683 tp = _xfs_trans_alloc(mp, XFS_TRANS_STRAT_WRITE, KM_NOFS); 684 tp->t_flags |= XFS_TRANS_RESERVE; 685 error = xfs_trans_reserve(tp, resblks, 686 XFS_WRITE_LOG_RES(mp), 0, 687 XFS_TRANS_PERM_LOG_RES, 688 XFS_WRITE_LOG_COUNT); 689 if (error) { 690 xfs_trans_cancel(tp, 0); 691 return XFS_ERROR(error); 692 } 693 694 xfs_ilock(ip, XFS_ILOCK_EXCL); 695 xfs_trans_ijoin(tp, ip, 0); 696 697 /* 698 * Modify the unwritten extent state of the buffer. 699 */ 700 xfs_bmap_init(&free_list, &firstfsb); 701 nimaps = 1; 702 error = xfs_bmapi_write(tp, ip, offset_fsb, count_fsb, 703 XFS_BMAPI_CONVERT, &firstfsb, 704 1, &imap, &nimaps, &free_list); 705 if (error) 706 goto error_on_bmapi_transaction; 707 708 error = xfs_bmap_finish(&(tp), &(free_list), &committed); 709 if (error) 710 goto error_on_bmapi_transaction; 711 712 error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES); 713 xfs_iunlock(ip, XFS_ILOCK_EXCL); 714 if (error) 715 return XFS_ERROR(error); 716 717 if (!(imap.br_startblock || XFS_IS_REALTIME_INODE(ip))) 718 return xfs_alert_fsblock_zero(ip, &imap); 719 720 if ((numblks_fsb = imap.br_blockcount) == 0) { 721 /* 722 * The numblks_fsb value should always get 723 * smaller, otherwise the loop is stuck. 724 */ 725 ASSERT(imap.br_blockcount); 726 break; 727 } 728 offset_fsb += numblks_fsb; 729 count_fsb -= numblks_fsb; 730 } while (count_fsb > 0); 731 732 return 0; 733 734 error_on_bmapi_transaction: 735 xfs_bmap_cancel(&free_list); 736 xfs_trans_cancel(tp, (XFS_TRANS_RELEASE_LOG_RES | XFS_TRANS_ABORT)); 737 xfs_iunlock(ip, XFS_ILOCK_EXCL); 738 return XFS_ERROR(error); 739 } 740