1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright (c) 2000-2006 Silicon Graphics, Inc. 4 * Copyright (c) 2012 Red Hat, Inc. 5 * All Rights Reserved. 6 */ 7 #include "xfs.h" 8 #include "xfs_fs.h" 9 #include "xfs_shared.h" 10 #include "xfs_format.h" 11 #include "xfs_log_format.h" 12 #include "xfs_trans_resv.h" 13 #include "xfs_bit.h" 14 #include "xfs_mount.h" 15 #include "xfs_defer.h" 16 #include "xfs_inode.h" 17 #include "xfs_btree.h" 18 #include "xfs_trans.h" 19 #include "xfs_alloc.h" 20 #include "xfs_bmap.h" 21 #include "xfs_bmap_util.h" 22 #include "xfs_bmap_btree.h" 23 #include "xfs_rtalloc.h" 24 #include "xfs_error.h" 25 #include "xfs_quota.h" 26 #include "xfs_trans_space.h" 27 #include "xfs_trace.h" 28 #include "xfs_icache.h" 29 #include "xfs_iomap.h" 30 #include "xfs_reflink.h" 31 #include "xfs_rtbitmap.h" 32 33 /* Kernel only BMAP related definitions and functions */ 34 35 /* 36 * Convert the given file system block to a disk block. We have to treat it 37 * differently based on whether the file is a real time file or not, because the 38 * bmap code does. 39 */ 40 xfs_daddr_t 41 xfs_fsb_to_db(struct xfs_inode *ip, xfs_fsblock_t fsb) 42 { 43 if (XFS_IS_REALTIME_INODE(ip)) 44 return XFS_FSB_TO_BB(ip->i_mount, fsb); 45 return XFS_FSB_TO_DADDR(ip->i_mount, fsb); 46 } 47 48 /* 49 * Routine to zero an extent on disk allocated to the specific inode. 50 * 51 * The VFS functions take a linearised filesystem block offset, so we have to 52 * convert the sparse xfs fsb to the right format first. 53 * VFS types are real funky, too. 54 */ 55 int 56 xfs_zero_extent( 57 struct xfs_inode *ip, 58 xfs_fsblock_t start_fsb, 59 xfs_off_t count_fsb) 60 { 61 struct xfs_mount *mp = ip->i_mount; 62 struct xfs_buftarg *target = xfs_inode_buftarg(ip); 63 xfs_daddr_t sector = xfs_fsb_to_db(ip, start_fsb); 64 sector_t block = XFS_BB_TO_FSBT(mp, sector); 65 66 return blkdev_issue_zeroout(target->bt_bdev, 67 block << (mp->m_super->s_blocksize_bits - 9), 68 count_fsb << (mp->m_super->s_blocksize_bits - 9), 69 GFP_KERNEL, 0); 70 } 71 72 /* 73 * Extent tree block counting routines. 74 */ 75 76 /* 77 * Count leaf blocks given a range of extent records. Delayed allocation 78 * extents are not counted towards the totals. 79 */ 80 xfs_extnum_t 81 xfs_bmap_count_leaves( 82 struct xfs_ifork *ifp, 83 xfs_filblks_t *count) 84 { 85 struct xfs_iext_cursor icur; 86 struct xfs_bmbt_irec got; 87 xfs_extnum_t numrecs = 0; 88 89 for_each_xfs_iext(ifp, &icur, &got) { 90 if (!isnullstartblock(got.br_startblock)) { 91 *count += got.br_blockcount; 92 numrecs++; 93 } 94 } 95 96 return numrecs; 97 } 98 99 /* 100 * Count fsblocks of the given fork. Delayed allocation extents are 101 * not counted towards the totals. 102 */ 103 int 104 xfs_bmap_count_blocks( 105 struct xfs_trans *tp, 106 struct xfs_inode *ip, 107 int whichfork, 108 xfs_extnum_t *nextents, 109 xfs_filblks_t *count) 110 { 111 struct xfs_mount *mp = ip->i_mount; 112 struct xfs_ifork *ifp = xfs_ifork_ptr(ip, whichfork); 113 struct xfs_btree_cur *cur; 114 xfs_extlen_t btblocks = 0; 115 int error; 116 117 *nextents = 0; 118 *count = 0; 119 120 if (!ifp) 121 return 0; 122 123 switch (ifp->if_format) { 124 case XFS_DINODE_FMT_BTREE: 125 error = xfs_iread_extents(tp, ip, whichfork); 126 if (error) 127 return error; 128 129 cur = xfs_bmbt_init_cursor(mp, tp, ip, whichfork); 130 error = xfs_btree_count_blocks(cur, &btblocks); 131 xfs_btree_del_cursor(cur, error); 132 if (error) 133 return error; 134 135 /* 136 * xfs_btree_count_blocks includes the root block contained in 137 * the inode fork in @btblocks, so subtract one because we're 138 * only interested in allocated disk blocks. 139 */ 140 *count += btblocks - 1; 141 142 fallthrough; 143 case XFS_DINODE_FMT_EXTENTS: 144 *nextents = xfs_bmap_count_leaves(ifp, count); 145 break; 146 } 147 148 return 0; 149 } 150 151 static int 152 xfs_getbmap_report_one( 153 struct xfs_inode *ip, 154 struct getbmapx *bmv, 155 struct kgetbmap *out, 156 int64_t bmv_end, 157 struct xfs_bmbt_irec *got) 158 { 159 struct kgetbmap *p = out + bmv->bmv_entries; 160 bool shared = false; 161 int error; 162 163 error = xfs_reflink_trim_around_shared(ip, got, &shared); 164 if (error) 165 return error; 166 167 if (isnullstartblock(got->br_startblock) || 168 got->br_startblock == DELAYSTARTBLOCK) { 169 /* 170 * Take the flush completion as being a point-in-time snapshot 171 * where there are no delalloc extents, and if any new ones 172 * have been created racily, just skip them as being 'after' 173 * the flush and so don't get reported. 174 */ 175 if (!(bmv->bmv_iflags & BMV_IF_DELALLOC)) 176 return 0; 177 178 p->bmv_oflags |= BMV_OF_DELALLOC; 179 p->bmv_block = -2; 180 } else { 181 p->bmv_block = xfs_fsb_to_db(ip, got->br_startblock); 182 } 183 184 if (got->br_state == XFS_EXT_UNWRITTEN && 185 (bmv->bmv_iflags & BMV_IF_PREALLOC)) 186 p->bmv_oflags |= BMV_OF_PREALLOC; 187 188 if (shared) 189 p->bmv_oflags |= BMV_OF_SHARED; 190 191 p->bmv_offset = XFS_FSB_TO_BB(ip->i_mount, got->br_startoff); 192 p->bmv_length = XFS_FSB_TO_BB(ip->i_mount, got->br_blockcount); 193 194 bmv->bmv_offset = p->bmv_offset + p->bmv_length; 195 bmv->bmv_length = max(0LL, bmv_end - bmv->bmv_offset); 196 bmv->bmv_entries++; 197 return 0; 198 } 199 200 static void 201 xfs_getbmap_report_hole( 202 struct xfs_inode *ip, 203 struct getbmapx *bmv, 204 struct kgetbmap *out, 205 int64_t bmv_end, 206 xfs_fileoff_t bno, 207 xfs_fileoff_t end) 208 { 209 struct kgetbmap *p = out + bmv->bmv_entries; 210 211 if (bmv->bmv_iflags & BMV_IF_NO_HOLES) 212 return; 213 214 p->bmv_block = -1; 215 p->bmv_offset = XFS_FSB_TO_BB(ip->i_mount, bno); 216 p->bmv_length = XFS_FSB_TO_BB(ip->i_mount, end - bno); 217 218 bmv->bmv_offset = p->bmv_offset + p->bmv_length; 219 bmv->bmv_length = max(0LL, bmv_end - bmv->bmv_offset); 220 bmv->bmv_entries++; 221 } 222 223 static inline bool 224 xfs_getbmap_full( 225 struct getbmapx *bmv) 226 { 227 return bmv->bmv_length == 0 || bmv->bmv_entries >= bmv->bmv_count - 1; 228 } 229 230 static bool 231 xfs_getbmap_next_rec( 232 struct xfs_bmbt_irec *rec, 233 xfs_fileoff_t total_end) 234 { 235 xfs_fileoff_t end = rec->br_startoff + rec->br_blockcount; 236 237 if (end == total_end) 238 return false; 239 240 rec->br_startoff += rec->br_blockcount; 241 if (!isnullstartblock(rec->br_startblock) && 242 rec->br_startblock != DELAYSTARTBLOCK) 243 rec->br_startblock += rec->br_blockcount; 244 rec->br_blockcount = total_end - end; 245 return true; 246 } 247 248 /* 249 * Get inode's extents as described in bmv, and format for output. 250 * Calls formatter to fill the user's buffer until all extents 251 * are mapped, until the passed-in bmv->bmv_count slots have 252 * been filled, or until the formatter short-circuits the loop, 253 * if it is tracking filled-in extents on its own. 254 */ 255 int /* error code */ 256 xfs_getbmap( 257 struct xfs_inode *ip, 258 struct getbmapx *bmv, /* user bmap structure */ 259 struct kgetbmap *out) 260 { 261 struct xfs_mount *mp = ip->i_mount; 262 int iflags = bmv->bmv_iflags; 263 int whichfork, lock, error = 0; 264 int64_t bmv_end, max_len; 265 xfs_fileoff_t bno, first_bno; 266 struct xfs_ifork *ifp; 267 struct xfs_bmbt_irec got, rec; 268 xfs_filblks_t len; 269 struct xfs_iext_cursor icur; 270 271 if (bmv->bmv_iflags & ~BMV_IF_VALID) 272 return -EINVAL; 273 #ifndef DEBUG 274 /* Only allow CoW fork queries if we're debugging. */ 275 if (iflags & BMV_IF_COWFORK) 276 return -EINVAL; 277 #endif 278 if ((iflags & BMV_IF_ATTRFORK) && (iflags & BMV_IF_COWFORK)) 279 return -EINVAL; 280 281 if (bmv->bmv_length < -1) 282 return -EINVAL; 283 bmv->bmv_entries = 0; 284 if (bmv->bmv_length == 0) 285 return 0; 286 287 if (iflags & BMV_IF_ATTRFORK) 288 whichfork = XFS_ATTR_FORK; 289 else if (iflags & BMV_IF_COWFORK) 290 whichfork = XFS_COW_FORK; 291 else 292 whichfork = XFS_DATA_FORK; 293 294 xfs_ilock(ip, XFS_IOLOCK_SHARED); 295 switch (whichfork) { 296 case XFS_ATTR_FORK: 297 lock = xfs_ilock_attr_map_shared(ip); 298 if (!xfs_inode_has_attr_fork(ip)) 299 goto out_unlock_ilock; 300 301 max_len = 1LL << 32; 302 break; 303 case XFS_COW_FORK: 304 lock = XFS_ILOCK_SHARED; 305 xfs_ilock(ip, lock); 306 307 /* No CoW fork? Just return */ 308 if (!xfs_ifork_ptr(ip, whichfork)) 309 goto out_unlock_ilock; 310 311 if (xfs_get_cowextsz_hint(ip)) 312 max_len = mp->m_super->s_maxbytes; 313 else 314 max_len = XFS_ISIZE(ip); 315 break; 316 case XFS_DATA_FORK: 317 if (!(iflags & BMV_IF_DELALLOC) && 318 (ip->i_delayed_blks || XFS_ISIZE(ip) > ip->i_disk_size)) { 319 error = filemap_write_and_wait(VFS_I(ip)->i_mapping); 320 if (error) 321 goto out_unlock_iolock; 322 323 /* 324 * Even after flushing the inode, there can still be 325 * delalloc blocks on the inode beyond EOF due to 326 * speculative preallocation. These are not removed 327 * until the release function is called or the inode 328 * is inactivated. Hence we cannot assert here that 329 * ip->i_delayed_blks == 0. 330 */ 331 } 332 333 if (xfs_get_extsz_hint(ip) || 334 (ip->i_diflags & 335 (XFS_DIFLAG_PREALLOC | XFS_DIFLAG_APPEND))) 336 max_len = mp->m_super->s_maxbytes; 337 else 338 max_len = XFS_ISIZE(ip); 339 340 lock = xfs_ilock_data_map_shared(ip); 341 break; 342 } 343 344 ifp = xfs_ifork_ptr(ip, whichfork); 345 346 switch (ifp->if_format) { 347 case XFS_DINODE_FMT_EXTENTS: 348 case XFS_DINODE_FMT_BTREE: 349 break; 350 case XFS_DINODE_FMT_LOCAL: 351 /* Local format inode forks report no extents. */ 352 goto out_unlock_ilock; 353 default: 354 error = -EINVAL; 355 goto out_unlock_ilock; 356 } 357 358 if (bmv->bmv_length == -1) { 359 max_len = XFS_FSB_TO_BB(mp, XFS_B_TO_FSB(mp, max_len)); 360 bmv->bmv_length = max(0LL, max_len - bmv->bmv_offset); 361 } 362 363 bmv_end = bmv->bmv_offset + bmv->bmv_length; 364 365 first_bno = bno = XFS_BB_TO_FSBT(mp, bmv->bmv_offset); 366 len = XFS_BB_TO_FSB(mp, bmv->bmv_length); 367 368 error = xfs_iread_extents(NULL, ip, whichfork); 369 if (error) 370 goto out_unlock_ilock; 371 372 if (!xfs_iext_lookup_extent(ip, ifp, bno, &icur, &got)) { 373 /* 374 * Report a whole-file hole if the delalloc flag is set to 375 * stay compatible with the old implementation. 376 */ 377 if (iflags & BMV_IF_DELALLOC) 378 xfs_getbmap_report_hole(ip, bmv, out, bmv_end, bno, 379 XFS_B_TO_FSB(mp, XFS_ISIZE(ip))); 380 goto out_unlock_ilock; 381 } 382 383 while (!xfs_getbmap_full(bmv)) { 384 xfs_trim_extent(&got, first_bno, len); 385 386 /* 387 * Report an entry for a hole if this extent doesn't directly 388 * follow the previous one. 389 */ 390 if (got.br_startoff > bno) { 391 xfs_getbmap_report_hole(ip, bmv, out, bmv_end, bno, 392 got.br_startoff); 393 if (xfs_getbmap_full(bmv)) 394 break; 395 } 396 397 /* 398 * In order to report shared extents accurately, we report each 399 * distinct shared / unshared part of a single bmbt record with 400 * an individual getbmapx record. 401 */ 402 bno = got.br_startoff + got.br_blockcount; 403 rec = got; 404 do { 405 error = xfs_getbmap_report_one(ip, bmv, out, bmv_end, 406 &rec); 407 if (error || xfs_getbmap_full(bmv)) 408 goto out_unlock_ilock; 409 } while (xfs_getbmap_next_rec(&rec, bno)); 410 411 if (!xfs_iext_next_extent(ifp, &icur, &got)) { 412 xfs_fileoff_t end = XFS_B_TO_FSB(mp, XFS_ISIZE(ip)); 413 414 if (bmv->bmv_entries > 0) 415 out[bmv->bmv_entries - 1].bmv_oflags |= 416 BMV_OF_LAST; 417 418 if (whichfork != XFS_ATTR_FORK && bno < end && 419 !xfs_getbmap_full(bmv)) { 420 xfs_getbmap_report_hole(ip, bmv, out, bmv_end, 421 bno, end); 422 } 423 break; 424 } 425 426 if (bno >= first_bno + len) 427 break; 428 } 429 430 out_unlock_ilock: 431 xfs_iunlock(ip, lock); 432 out_unlock_iolock: 433 xfs_iunlock(ip, XFS_IOLOCK_SHARED); 434 return error; 435 } 436 437 /* 438 * Dead simple method of punching delalyed allocation blocks from a range in 439 * the inode. This will always punch out both the start and end blocks, even 440 * if the ranges only partially overlap them, so it is up to the caller to 441 * ensure that partial blocks are not passed in. 442 */ 443 void 444 xfs_bmap_punch_delalloc_range( 445 struct xfs_inode *ip, 446 xfs_off_t start_byte, 447 xfs_off_t end_byte) 448 { 449 struct xfs_mount *mp = ip->i_mount; 450 struct xfs_ifork *ifp = &ip->i_df; 451 xfs_fileoff_t start_fsb = XFS_B_TO_FSBT(mp, start_byte); 452 xfs_fileoff_t end_fsb = XFS_B_TO_FSB(mp, end_byte); 453 struct xfs_bmbt_irec got, del; 454 struct xfs_iext_cursor icur; 455 456 ASSERT(!xfs_need_iread_extents(ifp)); 457 458 xfs_ilock(ip, XFS_ILOCK_EXCL); 459 if (!xfs_iext_lookup_extent_before(ip, ifp, &end_fsb, &icur, &got)) 460 goto out_unlock; 461 462 while (got.br_startoff + got.br_blockcount > start_fsb) { 463 del = got; 464 xfs_trim_extent(&del, start_fsb, end_fsb - start_fsb); 465 466 /* 467 * A delete can push the cursor forward. Step back to the 468 * previous extent on non-delalloc or extents outside the 469 * target range. 470 */ 471 if (!del.br_blockcount || 472 !isnullstartblock(del.br_startblock)) { 473 if (!xfs_iext_prev_extent(ifp, &icur, &got)) 474 break; 475 continue; 476 } 477 478 xfs_bmap_del_extent_delay(ip, XFS_DATA_FORK, &icur, &got, &del); 479 if (!xfs_iext_get_extent(ifp, &icur, &got)) 480 break; 481 } 482 483 out_unlock: 484 xfs_iunlock(ip, XFS_ILOCK_EXCL); 485 } 486 487 /* 488 * Test whether it is appropriate to check an inode for and free post EOF 489 * blocks. 490 */ 491 bool 492 xfs_can_free_eofblocks( 493 struct xfs_inode *ip) 494 { 495 struct xfs_bmbt_irec imap; 496 struct xfs_mount *mp = ip->i_mount; 497 xfs_fileoff_t end_fsb; 498 xfs_fileoff_t last_fsb; 499 int nimaps = 1; 500 int error; 501 502 /* 503 * Caller must either hold the exclusive io lock; or be inactivating 504 * the inode, which guarantees there are no other users of the inode. 505 */ 506 if (!(VFS_I(ip)->i_state & I_FREEING)) 507 xfs_assert_ilocked(ip, XFS_IOLOCK_EXCL); 508 509 /* prealloc/delalloc exists only on regular files */ 510 if (!S_ISREG(VFS_I(ip)->i_mode)) 511 return false; 512 513 /* 514 * Zero sized files with no cached pages and delalloc blocks will not 515 * have speculative prealloc/delalloc blocks to remove. 516 */ 517 if (VFS_I(ip)->i_size == 0 && 518 VFS_I(ip)->i_mapping->nrpages == 0 && 519 ip->i_delayed_blks == 0) 520 return false; 521 522 /* If we haven't read in the extent list, then don't do it now. */ 523 if (xfs_need_iread_extents(&ip->i_df)) 524 return false; 525 526 /* 527 * Only free real extents for inodes with persistent preallocations or 528 * the append-only flag. 529 */ 530 if (ip->i_diflags & (XFS_DIFLAG_PREALLOC | XFS_DIFLAG_APPEND)) 531 if (ip->i_delayed_blks == 0) 532 return false; 533 534 /* 535 * Do not try to free post-EOF blocks if EOF is beyond the end of the 536 * range supported by the page cache, because the truncation will loop 537 * forever. 538 */ 539 end_fsb = XFS_B_TO_FSB(mp, (xfs_ufsize_t)XFS_ISIZE(ip)); 540 if (xfs_inode_has_bigrtalloc(ip)) 541 end_fsb = xfs_rtb_roundup_rtx(mp, end_fsb); 542 last_fsb = XFS_B_TO_FSB(mp, mp->m_super->s_maxbytes); 543 if (last_fsb <= end_fsb) 544 return false; 545 546 /* 547 * Look up the mapping for the first block past EOF. If we can't find 548 * it, there's nothing to free. 549 */ 550 xfs_ilock(ip, XFS_ILOCK_SHARED); 551 error = xfs_bmapi_read(ip, end_fsb, last_fsb - end_fsb, &imap, &nimaps, 552 0); 553 xfs_iunlock(ip, XFS_ILOCK_SHARED); 554 if (error || nimaps == 0) 555 return false; 556 557 /* 558 * If there's a real mapping there or there are delayed allocation 559 * reservations, then we have post-EOF blocks to try to free. 560 */ 561 return imap.br_startblock != HOLESTARTBLOCK || ip->i_delayed_blks; 562 } 563 564 /* 565 * This is called to free any blocks beyond eof. The caller must hold 566 * IOLOCK_EXCL unless we are in the inode reclaim path and have the only 567 * reference to the inode. 568 */ 569 int 570 xfs_free_eofblocks( 571 struct xfs_inode *ip) 572 { 573 struct xfs_trans *tp; 574 struct xfs_mount *mp = ip->i_mount; 575 int error; 576 577 /* Attach the dquots to the inode up front. */ 578 error = xfs_qm_dqattach(ip); 579 if (error) 580 return error; 581 582 /* Wait on dio to ensure i_size has settled. */ 583 inode_dio_wait(VFS_I(ip)); 584 585 /* 586 * For preallocated files only free delayed allocations. 587 * 588 * Note that this means we also leave speculative preallocations in 589 * place for preallocated files. 590 */ 591 if (ip->i_diflags & (XFS_DIFLAG_PREALLOC | XFS_DIFLAG_APPEND)) { 592 if (ip->i_delayed_blks) { 593 xfs_bmap_punch_delalloc_range(ip, 594 round_up(XFS_ISIZE(ip), mp->m_sb.sb_blocksize), 595 LLONG_MAX); 596 } 597 xfs_inode_clear_eofblocks_tag(ip); 598 return 0; 599 } 600 601 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_itruncate, 0, 0, 0, &tp); 602 if (error) { 603 ASSERT(xfs_is_shutdown(mp)); 604 return error; 605 } 606 607 xfs_ilock(ip, XFS_ILOCK_EXCL); 608 xfs_trans_ijoin(tp, ip, 0); 609 610 /* 611 * Do not update the on-disk file size. If we update the on-disk file 612 * size and then the system crashes before the contents of the file are 613 * flushed to disk then the files may be full of holes (ie NULL files 614 * bug). 615 */ 616 error = xfs_itruncate_extents_flags(&tp, ip, XFS_DATA_FORK, 617 XFS_ISIZE(ip), XFS_BMAPI_NODISCARD); 618 if (error) 619 goto err_cancel; 620 621 error = xfs_trans_commit(tp); 622 if (error) 623 goto out_unlock; 624 625 xfs_inode_clear_eofblocks_tag(ip); 626 goto out_unlock; 627 628 err_cancel: 629 /* 630 * If we get an error at this point we simply don't 631 * bother truncating the file. 632 */ 633 xfs_trans_cancel(tp); 634 out_unlock: 635 xfs_iunlock(ip, XFS_ILOCK_EXCL); 636 return error; 637 } 638 639 int 640 xfs_alloc_file_space( 641 struct xfs_inode *ip, 642 xfs_off_t offset, 643 xfs_off_t len) 644 { 645 xfs_mount_t *mp = ip->i_mount; 646 xfs_off_t count; 647 xfs_filblks_t allocatesize_fsb; 648 xfs_extlen_t extsz, temp; 649 xfs_fileoff_t startoffset_fsb; 650 xfs_fileoff_t endoffset_fsb; 651 int rt; 652 xfs_trans_t *tp; 653 xfs_bmbt_irec_t imaps[1], *imapp; 654 int error; 655 656 trace_xfs_alloc_file_space(ip); 657 658 if (xfs_is_shutdown(mp)) 659 return -EIO; 660 661 error = xfs_qm_dqattach(ip); 662 if (error) 663 return error; 664 665 if (len <= 0) 666 return -EINVAL; 667 668 rt = XFS_IS_REALTIME_INODE(ip); 669 extsz = xfs_get_extsz_hint(ip); 670 671 count = len; 672 imapp = &imaps[0]; 673 startoffset_fsb = XFS_B_TO_FSBT(mp, offset); 674 endoffset_fsb = XFS_B_TO_FSB(mp, offset + count); 675 allocatesize_fsb = endoffset_fsb - startoffset_fsb; 676 677 /* 678 * Allocate file space until done or until there is an error 679 */ 680 while (allocatesize_fsb && !error) { 681 xfs_fileoff_t s, e; 682 unsigned int dblocks, rblocks, resblks; 683 int nimaps = 1; 684 685 /* 686 * Determine space reservations for data/realtime. 687 */ 688 if (unlikely(extsz)) { 689 s = startoffset_fsb; 690 do_div(s, extsz); 691 s *= extsz; 692 e = startoffset_fsb + allocatesize_fsb; 693 div_u64_rem(startoffset_fsb, extsz, &temp); 694 if (temp) 695 e += temp; 696 div_u64_rem(e, extsz, &temp); 697 if (temp) 698 e += extsz - temp; 699 } else { 700 s = 0; 701 e = allocatesize_fsb; 702 } 703 704 /* 705 * The transaction reservation is limited to a 32-bit block 706 * count, hence we need to limit the number of blocks we are 707 * trying to reserve to avoid an overflow. We can't allocate 708 * more than @nimaps extents, and an extent is limited on disk 709 * to XFS_BMBT_MAX_EXTLEN (21 bits), so use that to enforce the 710 * limit. 711 */ 712 resblks = min_t(xfs_fileoff_t, (e - s), 713 (XFS_MAX_BMBT_EXTLEN * nimaps)); 714 if (unlikely(rt)) { 715 dblocks = XFS_DIOSTRAT_SPACE_RES(mp, 0); 716 rblocks = resblks; 717 } else { 718 dblocks = XFS_DIOSTRAT_SPACE_RES(mp, resblks); 719 rblocks = 0; 720 } 721 722 error = xfs_trans_alloc_inode(ip, &M_RES(mp)->tr_write, 723 dblocks, rblocks, false, &tp); 724 if (error) 725 break; 726 727 error = xfs_iext_count_extend(tp, ip, XFS_DATA_FORK, 728 XFS_IEXT_ADD_NOSPLIT_CNT); 729 if (error) 730 goto error; 731 732 /* 733 * If the allocator cannot find a single free extent large 734 * enough to cover the start block of the requested range, 735 * xfs_bmapi_write will return -ENOSR. 736 * 737 * In that case we simply need to keep looping with the same 738 * startoffset_fsb so that one of the following allocations 739 * will eventually reach the requested range. 740 */ 741 error = xfs_bmapi_write(tp, ip, startoffset_fsb, 742 allocatesize_fsb, XFS_BMAPI_PREALLOC, 0, imapp, 743 &nimaps); 744 if (error) { 745 if (error != -ENOSR) 746 goto error; 747 error = 0; 748 } else { 749 startoffset_fsb += imapp->br_blockcount; 750 allocatesize_fsb -= imapp->br_blockcount; 751 } 752 753 ip->i_diflags |= XFS_DIFLAG_PREALLOC; 754 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE); 755 756 error = xfs_trans_commit(tp); 757 xfs_iunlock(ip, XFS_ILOCK_EXCL); 758 } 759 760 return error; 761 762 error: 763 xfs_trans_cancel(tp); 764 xfs_iunlock(ip, XFS_ILOCK_EXCL); 765 return error; 766 } 767 768 static int 769 xfs_unmap_extent( 770 struct xfs_inode *ip, 771 xfs_fileoff_t startoffset_fsb, 772 xfs_filblks_t len_fsb, 773 int *done) 774 { 775 struct xfs_mount *mp = ip->i_mount; 776 struct xfs_trans *tp; 777 uint resblks = XFS_DIOSTRAT_SPACE_RES(mp, 0); 778 int error; 779 780 error = xfs_trans_alloc_inode(ip, &M_RES(mp)->tr_write, resblks, 0, 781 false, &tp); 782 if (error) 783 return error; 784 785 error = xfs_iext_count_extend(tp, ip, XFS_DATA_FORK, 786 XFS_IEXT_PUNCH_HOLE_CNT); 787 if (error) 788 goto out_trans_cancel; 789 790 error = xfs_bunmapi(tp, ip, startoffset_fsb, len_fsb, 0, 2, done); 791 if (error) 792 goto out_trans_cancel; 793 794 error = xfs_trans_commit(tp); 795 out_unlock: 796 xfs_iunlock(ip, XFS_ILOCK_EXCL); 797 return error; 798 799 out_trans_cancel: 800 xfs_trans_cancel(tp); 801 goto out_unlock; 802 } 803 804 /* Caller must first wait for the completion of any pending DIOs if required. */ 805 int 806 xfs_flush_unmap_range( 807 struct xfs_inode *ip, 808 xfs_off_t offset, 809 xfs_off_t len) 810 { 811 struct inode *inode = VFS_I(ip); 812 xfs_off_t rounding, start, end; 813 int error; 814 815 /* 816 * Make sure we extend the flush out to extent alignment 817 * boundaries so any extent range overlapping the start/end 818 * of the modification we are about to do is clean and idle. 819 */ 820 rounding = max_t(xfs_off_t, xfs_inode_alloc_unitsize(ip), PAGE_SIZE); 821 start = rounddown_64(offset, rounding); 822 end = roundup_64(offset + len, rounding) - 1; 823 824 error = filemap_write_and_wait_range(inode->i_mapping, start, end); 825 if (error) 826 return error; 827 truncate_pagecache_range(inode, start, end); 828 return 0; 829 } 830 831 int 832 xfs_free_file_space( 833 struct xfs_inode *ip, 834 xfs_off_t offset, 835 xfs_off_t len) 836 { 837 struct xfs_mount *mp = ip->i_mount; 838 xfs_fileoff_t startoffset_fsb; 839 xfs_fileoff_t endoffset_fsb; 840 int done = 0, error; 841 842 trace_xfs_free_file_space(ip); 843 844 error = xfs_qm_dqattach(ip); 845 if (error) 846 return error; 847 848 if (len <= 0) /* if nothing being freed */ 849 return 0; 850 851 startoffset_fsb = XFS_B_TO_FSB(mp, offset); 852 endoffset_fsb = XFS_B_TO_FSBT(mp, offset + len); 853 854 /* We can only free complete realtime extents. */ 855 if (xfs_inode_has_bigrtalloc(ip)) { 856 startoffset_fsb = xfs_rtb_roundup_rtx(mp, startoffset_fsb); 857 endoffset_fsb = xfs_rtb_rounddown_rtx(mp, endoffset_fsb); 858 } 859 860 /* 861 * Need to zero the stuff we're not freeing, on disk. 862 */ 863 if (endoffset_fsb > startoffset_fsb) { 864 while (!done) { 865 error = xfs_unmap_extent(ip, startoffset_fsb, 866 endoffset_fsb - startoffset_fsb, &done); 867 if (error) 868 return error; 869 } 870 } 871 872 /* 873 * Now that we've unmap all full blocks we'll have to zero out any 874 * partial block at the beginning and/or end. xfs_zero_range is smart 875 * enough to skip any holes, including those we just created, but we 876 * must take care not to zero beyond EOF and enlarge i_size. 877 */ 878 if (offset >= XFS_ISIZE(ip)) 879 return 0; 880 if (offset + len > XFS_ISIZE(ip)) 881 len = XFS_ISIZE(ip) - offset; 882 error = xfs_zero_range(ip, offset, len, NULL); 883 if (error) 884 return error; 885 886 /* 887 * If we zeroed right up to EOF and EOF straddles a page boundary we 888 * must make sure that the post-EOF area is also zeroed because the 889 * page could be mmap'd and xfs_zero_range doesn't do that for us. 890 * Writeback of the eof page will do this, albeit clumsily. 891 */ 892 if (offset + len >= XFS_ISIZE(ip) && offset_in_page(offset + len) > 0) { 893 error = filemap_write_and_wait_range(VFS_I(ip)->i_mapping, 894 round_down(offset + len, PAGE_SIZE), LLONG_MAX); 895 } 896 897 return error; 898 } 899 900 static int 901 xfs_prepare_shift( 902 struct xfs_inode *ip, 903 loff_t offset) 904 { 905 unsigned int rounding; 906 int error; 907 908 /* 909 * Trim eofblocks to avoid shifting uninitialized post-eof preallocation 910 * into the accessible region of the file. 911 */ 912 if (xfs_can_free_eofblocks(ip)) { 913 error = xfs_free_eofblocks(ip); 914 if (error) 915 return error; 916 } 917 918 /* 919 * Shift operations must stabilize the start block offset boundary along 920 * with the full range of the operation. If we don't, a COW writeback 921 * completion could race with an insert, front merge with the start 922 * extent (after split) during the shift and corrupt the file. Start 923 * with the allocation unit just prior to the start to stabilize the 924 * boundary. 925 */ 926 rounding = xfs_inode_alloc_unitsize(ip); 927 offset = rounddown_64(offset, rounding); 928 if (offset) 929 offset -= rounding; 930 931 /* 932 * Writeback and invalidate cache for the remainder of the file as we're 933 * about to shift down every extent from offset to EOF. 934 */ 935 error = xfs_flush_unmap_range(ip, offset, XFS_ISIZE(ip)); 936 if (error) 937 return error; 938 939 /* 940 * Clean out anything hanging around in the cow fork now that 941 * we've flushed all the dirty data out to disk to avoid having 942 * CoW extents at the wrong offsets. 943 */ 944 if (xfs_inode_has_cow_data(ip)) { 945 error = xfs_reflink_cancel_cow_range(ip, offset, NULLFILEOFF, 946 true); 947 if (error) 948 return error; 949 } 950 951 return 0; 952 } 953 954 /* 955 * xfs_collapse_file_space() 956 * This routine frees disk space and shift extent for the given file. 957 * The first thing we do is to free data blocks in the specified range 958 * by calling xfs_free_file_space(). It would also sync dirty data 959 * and invalidate page cache over the region on which collapse range 960 * is working. And Shift extent records to the left to cover a hole. 961 * RETURNS: 962 * 0 on success 963 * errno on error 964 * 965 */ 966 int 967 xfs_collapse_file_space( 968 struct xfs_inode *ip, 969 xfs_off_t offset, 970 xfs_off_t len) 971 { 972 struct xfs_mount *mp = ip->i_mount; 973 struct xfs_trans *tp; 974 int error; 975 xfs_fileoff_t next_fsb = XFS_B_TO_FSB(mp, offset + len); 976 xfs_fileoff_t shift_fsb = XFS_B_TO_FSB(mp, len); 977 bool done = false; 978 979 xfs_assert_ilocked(ip, XFS_IOLOCK_EXCL | XFS_MMAPLOCK_EXCL); 980 981 trace_xfs_collapse_file_space(ip); 982 983 error = xfs_free_file_space(ip, offset, len); 984 if (error) 985 return error; 986 987 error = xfs_prepare_shift(ip, offset); 988 if (error) 989 return error; 990 991 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, 0, 0, 0, &tp); 992 if (error) 993 return error; 994 995 xfs_ilock(ip, XFS_ILOCK_EXCL); 996 xfs_trans_ijoin(tp, ip, 0); 997 998 while (!done) { 999 error = xfs_bmap_collapse_extents(tp, ip, &next_fsb, shift_fsb, 1000 &done); 1001 if (error) 1002 goto out_trans_cancel; 1003 if (done) 1004 break; 1005 1006 /* finish any deferred frees and roll the transaction */ 1007 error = xfs_defer_finish(&tp); 1008 if (error) 1009 goto out_trans_cancel; 1010 } 1011 1012 error = xfs_trans_commit(tp); 1013 xfs_iunlock(ip, XFS_ILOCK_EXCL); 1014 return error; 1015 1016 out_trans_cancel: 1017 xfs_trans_cancel(tp); 1018 xfs_iunlock(ip, XFS_ILOCK_EXCL); 1019 return error; 1020 } 1021 1022 /* 1023 * xfs_insert_file_space() 1024 * This routine create hole space by shifting extents for the given file. 1025 * The first thing we do is to sync dirty data and invalidate page cache 1026 * over the region on which insert range is working. And split an extent 1027 * to two extents at given offset by calling xfs_bmap_split_extent. 1028 * And shift all extent records which are laying between [offset, 1029 * last allocated extent] to the right to reserve hole range. 1030 * RETURNS: 1031 * 0 on success 1032 * errno on error 1033 */ 1034 int 1035 xfs_insert_file_space( 1036 struct xfs_inode *ip, 1037 loff_t offset, 1038 loff_t len) 1039 { 1040 struct xfs_mount *mp = ip->i_mount; 1041 struct xfs_trans *tp; 1042 int error; 1043 xfs_fileoff_t stop_fsb = XFS_B_TO_FSB(mp, offset); 1044 xfs_fileoff_t next_fsb = NULLFSBLOCK; 1045 xfs_fileoff_t shift_fsb = XFS_B_TO_FSB(mp, len); 1046 bool done = false; 1047 1048 xfs_assert_ilocked(ip, XFS_IOLOCK_EXCL | XFS_MMAPLOCK_EXCL); 1049 1050 trace_xfs_insert_file_space(ip); 1051 1052 error = xfs_bmap_can_insert_extents(ip, stop_fsb, shift_fsb); 1053 if (error) 1054 return error; 1055 1056 error = xfs_prepare_shift(ip, offset); 1057 if (error) 1058 return error; 1059 1060 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, 1061 XFS_DIOSTRAT_SPACE_RES(mp, 0), 0, 0, &tp); 1062 if (error) 1063 return error; 1064 1065 xfs_ilock(ip, XFS_ILOCK_EXCL); 1066 xfs_trans_ijoin(tp, ip, 0); 1067 1068 error = xfs_iext_count_extend(tp, ip, XFS_DATA_FORK, 1069 XFS_IEXT_PUNCH_HOLE_CNT); 1070 if (error) 1071 goto out_trans_cancel; 1072 1073 /* 1074 * The extent shifting code works on extent granularity. So, if stop_fsb 1075 * is not the starting block of extent, we need to split the extent at 1076 * stop_fsb. 1077 */ 1078 error = xfs_bmap_split_extent(tp, ip, stop_fsb); 1079 if (error) 1080 goto out_trans_cancel; 1081 1082 do { 1083 error = xfs_defer_finish(&tp); 1084 if (error) 1085 goto out_trans_cancel; 1086 1087 error = xfs_bmap_insert_extents(tp, ip, &next_fsb, shift_fsb, 1088 &done, stop_fsb); 1089 if (error) 1090 goto out_trans_cancel; 1091 } while (!done); 1092 1093 error = xfs_trans_commit(tp); 1094 xfs_iunlock(ip, XFS_ILOCK_EXCL); 1095 return error; 1096 1097 out_trans_cancel: 1098 xfs_trans_cancel(tp); 1099 xfs_iunlock(ip, XFS_ILOCK_EXCL); 1100 return error; 1101 } 1102 1103 /* 1104 * We need to check that the format of the data fork in the temporary inode is 1105 * valid for the target inode before doing the swap. This is not a problem with 1106 * attr1 because of the fixed fork offset, but attr2 has a dynamically sized 1107 * data fork depending on the space the attribute fork is taking so we can get 1108 * invalid formats on the target inode. 1109 * 1110 * E.g. target has space for 7 extents in extent format, temp inode only has 1111 * space for 6. If we defragment down to 7 extents, then the tmp format is a 1112 * btree, but when swapped it needs to be in extent format. Hence we can't just 1113 * blindly swap data forks on attr2 filesystems. 1114 * 1115 * Note that we check the swap in both directions so that we don't end up with 1116 * a corrupt temporary inode, either. 1117 * 1118 * Note that fixing the way xfs_fsr sets up the attribute fork in the source 1119 * inode will prevent this situation from occurring, so all we do here is 1120 * reject and log the attempt. basically we are putting the responsibility on 1121 * userspace to get this right. 1122 */ 1123 static int 1124 xfs_swap_extents_check_format( 1125 struct xfs_inode *ip, /* target inode */ 1126 struct xfs_inode *tip) /* tmp inode */ 1127 { 1128 struct xfs_ifork *ifp = &ip->i_df; 1129 struct xfs_ifork *tifp = &tip->i_df; 1130 1131 /* User/group/project quota ids must match if quotas are enforced. */ 1132 if (XFS_IS_QUOTA_ON(ip->i_mount) && 1133 (!uid_eq(VFS_I(ip)->i_uid, VFS_I(tip)->i_uid) || 1134 !gid_eq(VFS_I(ip)->i_gid, VFS_I(tip)->i_gid) || 1135 ip->i_projid != tip->i_projid)) 1136 return -EINVAL; 1137 1138 /* Should never get a local format */ 1139 if (ifp->if_format == XFS_DINODE_FMT_LOCAL || 1140 tifp->if_format == XFS_DINODE_FMT_LOCAL) 1141 return -EINVAL; 1142 1143 /* 1144 * if the target inode has less extents that then temporary inode then 1145 * why did userspace call us? 1146 */ 1147 if (ifp->if_nextents < tifp->if_nextents) 1148 return -EINVAL; 1149 1150 /* 1151 * If we have to use the (expensive) rmap swap method, we can 1152 * handle any number of extents and any format. 1153 */ 1154 if (xfs_has_rmapbt(ip->i_mount)) 1155 return 0; 1156 1157 /* 1158 * if the target inode is in extent form and the temp inode is in btree 1159 * form then we will end up with the target inode in the wrong format 1160 * as we already know there are less extents in the temp inode. 1161 */ 1162 if (ifp->if_format == XFS_DINODE_FMT_EXTENTS && 1163 tifp->if_format == XFS_DINODE_FMT_BTREE) 1164 return -EINVAL; 1165 1166 /* Check temp in extent form to max in target */ 1167 if (tifp->if_format == XFS_DINODE_FMT_EXTENTS && 1168 tifp->if_nextents > XFS_IFORK_MAXEXT(ip, XFS_DATA_FORK)) 1169 return -EINVAL; 1170 1171 /* Check target in extent form to max in temp */ 1172 if (ifp->if_format == XFS_DINODE_FMT_EXTENTS && 1173 ifp->if_nextents > XFS_IFORK_MAXEXT(tip, XFS_DATA_FORK)) 1174 return -EINVAL; 1175 1176 /* 1177 * If we are in a btree format, check that the temp root block will fit 1178 * in the target and that it has enough extents to be in btree format 1179 * in the target. 1180 * 1181 * Note that we have to be careful to allow btree->extent conversions 1182 * (a common defrag case) which will occur when the temp inode is in 1183 * extent format... 1184 */ 1185 if (tifp->if_format == XFS_DINODE_FMT_BTREE) { 1186 if (xfs_inode_has_attr_fork(ip) && 1187 XFS_BMAP_BMDR_SPACE(tifp->if_broot) > xfs_inode_fork_boff(ip)) 1188 return -EINVAL; 1189 if (tifp->if_nextents <= XFS_IFORK_MAXEXT(ip, XFS_DATA_FORK)) 1190 return -EINVAL; 1191 } 1192 1193 /* Reciprocal target->temp btree format checks */ 1194 if (ifp->if_format == XFS_DINODE_FMT_BTREE) { 1195 if (xfs_inode_has_attr_fork(tip) && 1196 XFS_BMAP_BMDR_SPACE(ip->i_df.if_broot) > xfs_inode_fork_boff(tip)) 1197 return -EINVAL; 1198 if (ifp->if_nextents <= XFS_IFORK_MAXEXT(tip, XFS_DATA_FORK)) 1199 return -EINVAL; 1200 } 1201 1202 return 0; 1203 } 1204 1205 static int 1206 xfs_swap_extent_flush( 1207 struct xfs_inode *ip) 1208 { 1209 int error; 1210 1211 error = filemap_write_and_wait(VFS_I(ip)->i_mapping); 1212 if (error) 1213 return error; 1214 truncate_pagecache_range(VFS_I(ip), 0, -1); 1215 1216 /* Verify O_DIRECT for ftmp */ 1217 if (VFS_I(ip)->i_mapping->nrpages) 1218 return -EINVAL; 1219 return 0; 1220 } 1221 1222 /* 1223 * Move extents from one file to another, when rmap is enabled. 1224 */ 1225 STATIC int 1226 xfs_swap_extent_rmap( 1227 struct xfs_trans **tpp, 1228 struct xfs_inode *ip, 1229 struct xfs_inode *tip) 1230 { 1231 struct xfs_trans *tp = *tpp; 1232 struct xfs_bmbt_irec irec; 1233 struct xfs_bmbt_irec uirec; 1234 struct xfs_bmbt_irec tirec; 1235 xfs_fileoff_t offset_fsb; 1236 xfs_fileoff_t end_fsb; 1237 xfs_filblks_t count_fsb; 1238 int error; 1239 xfs_filblks_t ilen; 1240 xfs_filblks_t rlen; 1241 int nimaps; 1242 uint64_t tip_flags2; 1243 1244 /* 1245 * If the source file has shared blocks, we must flag the donor 1246 * file as having shared blocks so that we get the shared-block 1247 * rmap functions when we go to fix up the rmaps. The flags 1248 * will be switch for reals later. 1249 */ 1250 tip_flags2 = tip->i_diflags2; 1251 if (ip->i_diflags2 & XFS_DIFLAG2_REFLINK) 1252 tip->i_diflags2 |= XFS_DIFLAG2_REFLINK; 1253 1254 offset_fsb = 0; 1255 end_fsb = XFS_B_TO_FSB(ip->i_mount, i_size_read(VFS_I(ip))); 1256 count_fsb = (xfs_filblks_t)(end_fsb - offset_fsb); 1257 1258 while (count_fsb) { 1259 /* Read extent from the donor file */ 1260 nimaps = 1; 1261 error = xfs_bmapi_read(tip, offset_fsb, count_fsb, &tirec, 1262 &nimaps, 0); 1263 if (error) 1264 goto out; 1265 ASSERT(nimaps == 1); 1266 ASSERT(tirec.br_startblock != DELAYSTARTBLOCK); 1267 1268 trace_xfs_swap_extent_rmap_remap(tip, &tirec); 1269 ilen = tirec.br_blockcount; 1270 1271 /* Unmap the old blocks in the source file. */ 1272 while (tirec.br_blockcount) { 1273 ASSERT(tp->t_highest_agno == NULLAGNUMBER); 1274 trace_xfs_swap_extent_rmap_remap_piece(tip, &tirec); 1275 1276 /* Read extent from the source file */ 1277 nimaps = 1; 1278 error = xfs_bmapi_read(ip, tirec.br_startoff, 1279 tirec.br_blockcount, &irec, 1280 &nimaps, 0); 1281 if (error) 1282 goto out; 1283 ASSERT(nimaps == 1); 1284 ASSERT(tirec.br_startoff == irec.br_startoff); 1285 trace_xfs_swap_extent_rmap_remap_piece(ip, &irec); 1286 1287 /* Trim the extent. */ 1288 uirec = tirec; 1289 uirec.br_blockcount = rlen = min_t(xfs_filblks_t, 1290 tirec.br_blockcount, 1291 irec.br_blockcount); 1292 trace_xfs_swap_extent_rmap_remap_piece(tip, &uirec); 1293 1294 if (xfs_bmap_is_real_extent(&uirec)) { 1295 error = xfs_iext_count_extend(tp, ip, 1296 XFS_DATA_FORK, 1297 XFS_IEXT_SWAP_RMAP_CNT); 1298 if (error) 1299 goto out; 1300 } 1301 1302 if (xfs_bmap_is_real_extent(&irec)) { 1303 error = xfs_iext_count_extend(tp, tip, 1304 XFS_DATA_FORK, 1305 XFS_IEXT_SWAP_RMAP_CNT); 1306 if (error) 1307 goto out; 1308 } 1309 1310 /* Remove the mapping from the donor file. */ 1311 xfs_bmap_unmap_extent(tp, tip, XFS_DATA_FORK, &uirec); 1312 1313 /* Remove the mapping from the source file. */ 1314 xfs_bmap_unmap_extent(tp, ip, XFS_DATA_FORK, &irec); 1315 1316 /* Map the donor file's blocks into the source file. */ 1317 xfs_bmap_map_extent(tp, ip, XFS_DATA_FORK, &uirec); 1318 1319 /* Map the source file's blocks into the donor file. */ 1320 xfs_bmap_map_extent(tp, tip, XFS_DATA_FORK, &irec); 1321 1322 error = xfs_defer_finish(tpp); 1323 tp = *tpp; 1324 if (error) 1325 goto out; 1326 1327 tirec.br_startoff += rlen; 1328 if (tirec.br_startblock != HOLESTARTBLOCK && 1329 tirec.br_startblock != DELAYSTARTBLOCK) 1330 tirec.br_startblock += rlen; 1331 tirec.br_blockcount -= rlen; 1332 } 1333 1334 /* Roll on... */ 1335 count_fsb -= ilen; 1336 offset_fsb += ilen; 1337 } 1338 1339 tip->i_diflags2 = tip_flags2; 1340 return 0; 1341 1342 out: 1343 trace_xfs_swap_extent_rmap_error(ip, error, _RET_IP_); 1344 tip->i_diflags2 = tip_flags2; 1345 return error; 1346 } 1347 1348 /* Swap the extents of two files by swapping data forks. */ 1349 STATIC int 1350 xfs_swap_extent_forks( 1351 struct xfs_trans *tp, 1352 struct xfs_inode *ip, 1353 struct xfs_inode *tip, 1354 int *src_log_flags, 1355 int *target_log_flags) 1356 { 1357 xfs_filblks_t aforkblks = 0; 1358 xfs_filblks_t taforkblks = 0; 1359 xfs_extnum_t junk; 1360 uint64_t tmp; 1361 int error; 1362 1363 /* 1364 * Count the number of extended attribute blocks 1365 */ 1366 if (xfs_inode_has_attr_fork(ip) && ip->i_af.if_nextents > 0 && 1367 ip->i_af.if_format != XFS_DINODE_FMT_LOCAL) { 1368 error = xfs_bmap_count_blocks(tp, ip, XFS_ATTR_FORK, &junk, 1369 &aforkblks); 1370 if (error) 1371 return error; 1372 } 1373 if (xfs_inode_has_attr_fork(tip) && tip->i_af.if_nextents > 0 && 1374 tip->i_af.if_format != XFS_DINODE_FMT_LOCAL) { 1375 error = xfs_bmap_count_blocks(tp, tip, XFS_ATTR_FORK, &junk, 1376 &taforkblks); 1377 if (error) 1378 return error; 1379 } 1380 1381 /* 1382 * Btree format (v3) inodes have the inode number stamped in the bmbt 1383 * block headers. We can't start changing the bmbt blocks until the 1384 * inode owner change is logged so recovery does the right thing in the 1385 * event of a crash. Set the owner change log flags now and leave the 1386 * bmbt scan as the last step. 1387 */ 1388 if (xfs_has_v3inodes(ip->i_mount)) { 1389 if (ip->i_df.if_format == XFS_DINODE_FMT_BTREE) 1390 (*target_log_flags) |= XFS_ILOG_DOWNER; 1391 if (tip->i_df.if_format == XFS_DINODE_FMT_BTREE) 1392 (*src_log_flags) |= XFS_ILOG_DOWNER; 1393 } 1394 1395 /* 1396 * Swap the data forks of the inodes 1397 */ 1398 swap(ip->i_df, tip->i_df); 1399 1400 /* 1401 * Fix the on-disk inode values 1402 */ 1403 tmp = (uint64_t)ip->i_nblocks; 1404 ip->i_nblocks = tip->i_nblocks - taforkblks + aforkblks; 1405 tip->i_nblocks = tmp + taforkblks - aforkblks; 1406 1407 /* 1408 * The extents in the source inode could still contain speculative 1409 * preallocation beyond EOF (e.g. the file is open but not modified 1410 * while defrag is in progress). In that case, we need to copy over the 1411 * number of delalloc blocks the data fork in the source inode is 1412 * tracking beyond EOF so that when the fork is truncated away when the 1413 * temporary inode is unlinked we don't underrun the i_delayed_blks 1414 * counter on that inode. 1415 */ 1416 ASSERT(tip->i_delayed_blks == 0); 1417 tip->i_delayed_blks = ip->i_delayed_blks; 1418 ip->i_delayed_blks = 0; 1419 1420 switch (ip->i_df.if_format) { 1421 case XFS_DINODE_FMT_EXTENTS: 1422 (*src_log_flags) |= XFS_ILOG_DEXT; 1423 break; 1424 case XFS_DINODE_FMT_BTREE: 1425 ASSERT(!xfs_has_v3inodes(ip->i_mount) || 1426 (*src_log_flags & XFS_ILOG_DOWNER)); 1427 (*src_log_flags) |= XFS_ILOG_DBROOT; 1428 break; 1429 } 1430 1431 switch (tip->i_df.if_format) { 1432 case XFS_DINODE_FMT_EXTENTS: 1433 (*target_log_flags) |= XFS_ILOG_DEXT; 1434 break; 1435 case XFS_DINODE_FMT_BTREE: 1436 (*target_log_flags) |= XFS_ILOG_DBROOT; 1437 ASSERT(!xfs_has_v3inodes(ip->i_mount) || 1438 (*target_log_flags & XFS_ILOG_DOWNER)); 1439 break; 1440 } 1441 1442 return 0; 1443 } 1444 1445 /* 1446 * Fix up the owners of the bmbt blocks to refer to the current inode. The 1447 * change owner scan attempts to order all modified buffers in the current 1448 * transaction. In the event of ordered buffer failure, the offending buffer is 1449 * physically logged as a fallback and the scan returns -EAGAIN. We must roll 1450 * the transaction in this case to replenish the fallback log reservation and 1451 * restart the scan. This process repeats until the scan completes. 1452 */ 1453 static int 1454 xfs_swap_change_owner( 1455 struct xfs_trans **tpp, 1456 struct xfs_inode *ip, 1457 struct xfs_inode *tmpip) 1458 { 1459 int error; 1460 struct xfs_trans *tp = *tpp; 1461 1462 do { 1463 error = xfs_bmbt_change_owner(tp, ip, XFS_DATA_FORK, ip->i_ino, 1464 NULL); 1465 /* success or fatal error */ 1466 if (error != -EAGAIN) 1467 break; 1468 1469 error = xfs_trans_roll(tpp); 1470 if (error) 1471 break; 1472 tp = *tpp; 1473 1474 /* 1475 * Redirty both inodes so they can relog and keep the log tail 1476 * moving forward. 1477 */ 1478 xfs_trans_ijoin(tp, ip, 0); 1479 xfs_trans_ijoin(tp, tmpip, 0); 1480 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE); 1481 xfs_trans_log_inode(tp, tmpip, XFS_ILOG_CORE); 1482 } while (true); 1483 1484 return error; 1485 } 1486 1487 int 1488 xfs_swap_extents( 1489 struct xfs_inode *ip, /* target inode */ 1490 struct xfs_inode *tip, /* tmp inode */ 1491 struct xfs_swapext *sxp) 1492 { 1493 struct xfs_mount *mp = ip->i_mount; 1494 struct xfs_trans *tp; 1495 struct xfs_bstat *sbp = &sxp->sx_stat; 1496 int src_log_flags, target_log_flags; 1497 int error = 0; 1498 uint64_t f; 1499 int resblks = 0; 1500 unsigned int flags = 0; 1501 struct timespec64 ctime, mtime; 1502 1503 /* 1504 * Lock the inodes against other IO, page faults and truncate to 1505 * begin with. Then we can ensure the inodes are flushed and have no 1506 * page cache safely. Once we have done this we can take the ilocks and 1507 * do the rest of the checks. 1508 */ 1509 lock_two_nondirectories(VFS_I(ip), VFS_I(tip)); 1510 filemap_invalidate_lock_two(VFS_I(ip)->i_mapping, 1511 VFS_I(tip)->i_mapping); 1512 1513 /* Verify that both files have the same format */ 1514 if ((VFS_I(ip)->i_mode & S_IFMT) != (VFS_I(tip)->i_mode & S_IFMT)) { 1515 error = -EINVAL; 1516 goto out_unlock; 1517 } 1518 1519 /* Verify both files are either real-time or non-realtime */ 1520 if (XFS_IS_REALTIME_INODE(ip) != XFS_IS_REALTIME_INODE(tip)) { 1521 error = -EINVAL; 1522 goto out_unlock; 1523 } 1524 1525 error = xfs_qm_dqattach(ip); 1526 if (error) 1527 goto out_unlock; 1528 1529 error = xfs_qm_dqattach(tip); 1530 if (error) 1531 goto out_unlock; 1532 1533 error = xfs_swap_extent_flush(ip); 1534 if (error) 1535 goto out_unlock; 1536 error = xfs_swap_extent_flush(tip); 1537 if (error) 1538 goto out_unlock; 1539 1540 if (xfs_inode_has_cow_data(tip)) { 1541 error = xfs_reflink_cancel_cow_range(tip, 0, NULLFILEOFF, true); 1542 if (error) 1543 goto out_unlock; 1544 } 1545 1546 /* 1547 * Extent "swapping" with rmap requires a permanent reservation and 1548 * a block reservation because it's really just a remap operation 1549 * performed with log redo items! 1550 */ 1551 if (xfs_has_rmapbt(mp)) { 1552 int w = XFS_DATA_FORK; 1553 uint32_t ipnext = ip->i_df.if_nextents; 1554 uint32_t tipnext = tip->i_df.if_nextents; 1555 1556 /* 1557 * Conceptually this shouldn't affect the shape of either bmbt, 1558 * but since we atomically move extents one by one, we reserve 1559 * enough space to rebuild both trees. 1560 */ 1561 resblks = XFS_SWAP_RMAP_SPACE_RES(mp, ipnext, w); 1562 resblks += XFS_SWAP_RMAP_SPACE_RES(mp, tipnext, w); 1563 1564 /* 1565 * If either inode straddles a bmapbt block allocation boundary, 1566 * the rmapbt algorithm triggers repeated allocs and frees as 1567 * extents are remapped. This can exhaust the block reservation 1568 * prematurely and cause shutdown. Return freed blocks to the 1569 * transaction reservation to counter this behavior. 1570 */ 1571 flags |= XFS_TRANS_RES_FDBLKS; 1572 } 1573 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, resblks, 0, flags, 1574 &tp); 1575 if (error) 1576 goto out_unlock; 1577 1578 /* 1579 * Lock and join the inodes to the tansaction so that transaction commit 1580 * or cancel will unlock the inodes from this point onwards. 1581 */ 1582 xfs_lock_two_inodes(ip, XFS_ILOCK_EXCL, tip, XFS_ILOCK_EXCL); 1583 xfs_trans_ijoin(tp, ip, 0); 1584 xfs_trans_ijoin(tp, tip, 0); 1585 1586 1587 /* Verify all data are being swapped */ 1588 if (sxp->sx_offset != 0 || 1589 sxp->sx_length != ip->i_disk_size || 1590 sxp->sx_length != tip->i_disk_size) { 1591 error = -EFAULT; 1592 goto out_trans_cancel; 1593 } 1594 1595 trace_xfs_swap_extent_before(ip, 0); 1596 trace_xfs_swap_extent_before(tip, 1); 1597 1598 /* check inode formats now that data is flushed */ 1599 error = xfs_swap_extents_check_format(ip, tip); 1600 if (error) { 1601 xfs_notice(mp, 1602 "%s: inode 0x%llx format is incompatible for exchanging.", 1603 __func__, ip->i_ino); 1604 goto out_trans_cancel; 1605 } 1606 1607 /* 1608 * Compare the current change & modify times with that 1609 * passed in. If they differ, we abort this swap. 1610 * This is the mechanism used to ensure the calling 1611 * process that the file was not changed out from 1612 * under it. 1613 */ 1614 ctime = inode_get_ctime(VFS_I(ip)); 1615 mtime = inode_get_mtime(VFS_I(ip)); 1616 if ((sbp->bs_ctime.tv_sec != ctime.tv_sec) || 1617 (sbp->bs_ctime.tv_nsec != ctime.tv_nsec) || 1618 (sbp->bs_mtime.tv_sec != mtime.tv_sec) || 1619 (sbp->bs_mtime.tv_nsec != mtime.tv_nsec)) { 1620 error = -EBUSY; 1621 goto out_trans_cancel; 1622 } 1623 1624 /* 1625 * Note the trickiness in setting the log flags - we set the owner log 1626 * flag on the opposite inode (i.e. the inode we are setting the new 1627 * owner to be) because once we swap the forks and log that, log 1628 * recovery is going to see the fork as owned by the swapped inode, 1629 * not the pre-swapped inodes. 1630 */ 1631 src_log_flags = XFS_ILOG_CORE; 1632 target_log_flags = XFS_ILOG_CORE; 1633 1634 if (xfs_has_rmapbt(mp)) 1635 error = xfs_swap_extent_rmap(&tp, ip, tip); 1636 else 1637 error = xfs_swap_extent_forks(tp, ip, tip, &src_log_flags, 1638 &target_log_flags); 1639 if (error) 1640 goto out_trans_cancel; 1641 1642 /* Do we have to swap reflink flags? */ 1643 if ((ip->i_diflags2 & XFS_DIFLAG2_REFLINK) ^ 1644 (tip->i_diflags2 & XFS_DIFLAG2_REFLINK)) { 1645 f = ip->i_diflags2 & XFS_DIFLAG2_REFLINK; 1646 ip->i_diflags2 &= ~XFS_DIFLAG2_REFLINK; 1647 ip->i_diflags2 |= tip->i_diflags2 & XFS_DIFLAG2_REFLINK; 1648 tip->i_diflags2 &= ~XFS_DIFLAG2_REFLINK; 1649 tip->i_diflags2 |= f & XFS_DIFLAG2_REFLINK; 1650 } 1651 1652 /* Swap the cow forks. */ 1653 if (xfs_has_reflink(mp)) { 1654 ASSERT(!ip->i_cowfp || 1655 ip->i_cowfp->if_format == XFS_DINODE_FMT_EXTENTS); 1656 ASSERT(!tip->i_cowfp || 1657 tip->i_cowfp->if_format == XFS_DINODE_FMT_EXTENTS); 1658 1659 swap(ip->i_cowfp, tip->i_cowfp); 1660 1661 if (ip->i_cowfp && ip->i_cowfp->if_bytes) 1662 xfs_inode_set_cowblocks_tag(ip); 1663 else 1664 xfs_inode_clear_cowblocks_tag(ip); 1665 if (tip->i_cowfp && tip->i_cowfp->if_bytes) 1666 xfs_inode_set_cowblocks_tag(tip); 1667 else 1668 xfs_inode_clear_cowblocks_tag(tip); 1669 } 1670 1671 xfs_trans_log_inode(tp, ip, src_log_flags); 1672 xfs_trans_log_inode(tp, tip, target_log_flags); 1673 1674 /* 1675 * The extent forks have been swapped, but crc=1,rmapbt=0 filesystems 1676 * have inode number owner values in the bmbt blocks that still refer to 1677 * the old inode. Scan each bmbt to fix up the owner values with the 1678 * inode number of the current inode. 1679 */ 1680 if (src_log_flags & XFS_ILOG_DOWNER) { 1681 error = xfs_swap_change_owner(&tp, ip, tip); 1682 if (error) 1683 goto out_trans_cancel; 1684 } 1685 if (target_log_flags & XFS_ILOG_DOWNER) { 1686 error = xfs_swap_change_owner(&tp, tip, ip); 1687 if (error) 1688 goto out_trans_cancel; 1689 } 1690 1691 /* 1692 * If this is a synchronous mount, make sure that the 1693 * transaction goes to disk before returning to the user. 1694 */ 1695 if (xfs_has_wsync(mp)) 1696 xfs_trans_set_sync(tp); 1697 1698 error = xfs_trans_commit(tp); 1699 1700 trace_xfs_swap_extent_after(ip, 0); 1701 trace_xfs_swap_extent_after(tip, 1); 1702 1703 out_unlock_ilock: 1704 xfs_iunlock(ip, XFS_ILOCK_EXCL); 1705 xfs_iunlock(tip, XFS_ILOCK_EXCL); 1706 out_unlock: 1707 filemap_invalidate_unlock_two(VFS_I(ip)->i_mapping, 1708 VFS_I(tip)->i_mapping); 1709 unlock_two_nondirectories(VFS_I(ip), VFS_I(tip)); 1710 return error; 1711 1712 out_trans_cancel: 1713 xfs_trans_cancel(tp); 1714 goto out_unlock_ilock; 1715 } 1716