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 if (xfs_is_always_cow_inode(ip)) 657 return 0; 658 659 trace_xfs_alloc_file_space(ip); 660 661 if (xfs_is_shutdown(mp)) 662 return -EIO; 663 664 error = xfs_qm_dqattach(ip); 665 if (error) 666 return error; 667 668 if (len <= 0) 669 return -EINVAL; 670 671 rt = XFS_IS_REALTIME_INODE(ip); 672 extsz = xfs_get_extsz_hint(ip); 673 674 count = len; 675 imapp = &imaps[0]; 676 startoffset_fsb = XFS_B_TO_FSBT(mp, offset); 677 endoffset_fsb = XFS_B_TO_FSB(mp, offset + count); 678 allocatesize_fsb = endoffset_fsb - startoffset_fsb; 679 680 /* 681 * Allocate file space until done or until there is an error 682 */ 683 while (allocatesize_fsb && !error) { 684 xfs_fileoff_t s, e; 685 unsigned int dblocks, rblocks, resblks; 686 int nimaps = 1; 687 688 /* 689 * Determine space reservations for data/realtime. 690 */ 691 if (unlikely(extsz)) { 692 s = startoffset_fsb; 693 do_div(s, extsz); 694 s *= extsz; 695 e = startoffset_fsb + allocatesize_fsb; 696 div_u64_rem(startoffset_fsb, extsz, &temp); 697 if (temp) 698 e += temp; 699 div_u64_rem(e, extsz, &temp); 700 if (temp) 701 e += extsz - temp; 702 } else { 703 s = 0; 704 e = allocatesize_fsb; 705 } 706 707 /* 708 * The transaction reservation is limited to a 32-bit block 709 * count, hence we need to limit the number of blocks we are 710 * trying to reserve to avoid an overflow. We can't allocate 711 * more than @nimaps extents, and an extent is limited on disk 712 * to XFS_BMBT_MAX_EXTLEN (21 bits), so use that to enforce the 713 * limit. 714 */ 715 resblks = min_t(xfs_fileoff_t, (e - s), 716 (XFS_MAX_BMBT_EXTLEN * nimaps)); 717 if (unlikely(rt)) { 718 dblocks = XFS_DIOSTRAT_SPACE_RES(mp, 0); 719 rblocks = resblks; 720 } else { 721 dblocks = XFS_DIOSTRAT_SPACE_RES(mp, resblks); 722 rblocks = 0; 723 } 724 725 error = xfs_trans_alloc_inode(ip, &M_RES(mp)->tr_write, 726 dblocks, rblocks, false, &tp); 727 if (error) 728 break; 729 730 error = xfs_iext_count_extend(tp, ip, XFS_DATA_FORK, 731 XFS_IEXT_ADD_NOSPLIT_CNT); 732 if (error) 733 goto error; 734 735 /* 736 * If the allocator cannot find a single free extent large 737 * enough to cover the start block of the requested range, 738 * xfs_bmapi_write will return -ENOSR. 739 * 740 * In that case we simply need to keep looping with the same 741 * startoffset_fsb so that one of the following allocations 742 * will eventually reach the requested range. 743 */ 744 error = xfs_bmapi_write(tp, ip, startoffset_fsb, 745 allocatesize_fsb, XFS_BMAPI_PREALLOC, 0, imapp, 746 &nimaps); 747 if (error) { 748 if (error != -ENOSR) 749 goto error; 750 error = 0; 751 } else { 752 startoffset_fsb += imapp->br_blockcount; 753 allocatesize_fsb -= imapp->br_blockcount; 754 } 755 756 ip->i_diflags |= XFS_DIFLAG_PREALLOC; 757 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE); 758 759 error = xfs_trans_commit(tp); 760 xfs_iunlock(ip, XFS_ILOCK_EXCL); 761 } 762 763 return error; 764 765 error: 766 xfs_trans_cancel(tp); 767 xfs_iunlock(ip, XFS_ILOCK_EXCL); 768 return error; 769 } 770 771 static int 772 xfs_unmap_extent( 773 struct xfs_inode *ip, 774 xfs_fileoff_t startoffset_fsb, 775 xfs_filblks_t len_fsb, 776 int *done) 777 { 778 struct xfs_mount *mp = ip->i_mount; 779 struct xfs_trans *tp; 780 uint resblks = XFS_DIOSTRAT_SPACE_RES(mp, 0); 781 int error; 782 783 error = xfs_trans_alloc_inode(ip, &M_RES(mp)->tr_write, resblks, 0, 784 false, &tp); 785 if (error) 786 return error; 787 788 error = xfs_iext_count_extend(tp, ip, XFS_DATA_FORK, 789 XFS_IEXT_PUNCH_HOLE_CNT); 790 if (error) 791 goto out_trans_cancel; 792 793 error = xfs_bunmapi(tp, ip, startoffset_fsb, len_fsb, 0, 2, done); 794 if (error) 795 goto out_trans_cancel; 796 797 error = xfs_trans_commit(tp); 798 out_unlock: 799 xfs_iunlock(ip, XFS_ILOCK_EXCL); 800 return error; 801 802 out_trans_cancel: 803 xfs_trans_cancel(tp); 804 goto out_unlock; 805 } 806 807 /* Caller must first wait for the completion of any pending DIOs if required. */ 808 int 809 xfs_flush_unmap_range( 810 struct xfs_inode *ip, 811 xfs_off_t offset, 812 xfs_off_t len) 813 { 814 struct inode *inode = VFS_I(ip); 815 xfs_off_t rounding, start, end; 816 int error; 817 818 /* 819 * Make sure we extend the flush out to extent alignment 820 * boundaries so any extent range overlapping the start/end 821 * of the modification we are about to do is clean and idle. 822 */ 823 rounding = max_t(xfs_off_t, xfs_inode_alloc_unitsize(ip), PAGE_SIZE); 824 start = rounddown_64(offset, rounding); 825 end = roundup_64(offset + len, rounding) - 1; 826 827 error = filemap_write_and_wait_range(inode->i_mapping, start, end); 828 if (error) 829 return error; 830 truncate_pagecache_range(inode, start, end); 831 return 0; 832 } 833 834 int 835 xfs_free_file_space( 836 struct xfs_inode *ip, 837 xfs_off_t offset, 838 xfs_off_t len) 839 { 840 struct xfs_mount *mp = ip->i_mount; 841 xfs_fileoff_t startoffset_fsb; 842 xfs_fileoff_t endoffset_fsb; 843 int done = 0, error; 844 845 trace_xfs_free_file_space(ip); 846 847 error = xfs_qm_dqattach(ip); 848 if (error) 849 return error; 850 851 if (len <= 0) /* if nothing being freed */ 852 return 0; 853 854 /* 855 * Now AIO and DIO has drained we flush and (if necessary) invalidate 856 * the cached range over the first operation we are about to run. 857 */ 858 error = xfs_flush_unmap_range(ip, offset, len); 859 if (error) 860 return error; 861 862 startoffset_fsb = XFS_B_TO_FSB(mp, offset); 863 endoffset_fsb = XFS_B_TO_FSBT(mp, offset + len); 864 865 /* We can only free complete realtime extents. */ 866 if (xfs_inode_has_bigrtalloc(ip)) { 867 startoffset_fsb = xfs_rtb_roundup_rtx(mp, startoffset_fsb); 868 endoffset_fsb = xfs_rtb_rounddown_rtx(mp, endoffset_fsb); 869 } 870 871 /* 872 * Need to zero the stuff we're not freeing, on disk. 873 */ 874 if (endoffset_fsb > startoffset_fsb) { 875 while (!done) { 876 error = xfs_unmap_extent(ip, startoffset_fsb, 877 endoffset_fsb - startoffset_fsb, &done); 878 if (error) 879 return error; 880 } 881 } 882 883 /* 884 * Now that we've unmap all full blocks we'll have to zero out any 885 * partial block at the beginning and/or end. xfs_zero_range is smart 886 * enough to skip any holes, including those we just created, but we 887 * must take care not to zero beyond EOF and enlarge i_size. 888 */ 889 if (offset >= XFS_ISIZE(ip)) 890 return 0; 891 if (offset + len > XFS_ISIZE(ip)) 892 len = XFS_ISIZE(ip) - offset; 893 error = xfs_zero_range(ip, offset, len, NULL); 894 if (error) 895 return error; 896 897 /* 898 * If we zeroed right up to EOF and EOF straddles a page boundary we 899 * must make sure that the post-EOF area is also zeroed because the 900 * page could be mmap'd and xfs_zero_range doesn't do that for us. 901 * Writeback of the eof page will do this, albeit clumsily. 902 */ 903 if (offset + len >= XFS_ISIZE(ip) && offset_in_page(offset + len) > 0) { 904 error = filemap_write_and_wait_range(VFS_I(ip)->i_mapping, 905 round_down(offset + len, PAGE_SIZE), LLONG_MAX); 906 } 907 908 return error; 909 } 910 911 static int 912 xfs_prepare_shift( 913 struct xfs_inode *ip, 914 loff_t offset) 915 { 916 unsigned int rounding; 917 int error; 918 919 /* 920 * Trim eofblocks to avoid shifting uninitialized post-eof preallocation 921 * into the accessible region of the file. 922 */ 923 if (xfs_can_free_eofblocks(ip)) { 924 error = xfs_free_eofblocks(ip); 925 if (error) 926 return error; 927 } 928 929 /* 930 * Shift operations must stabilize the start block offset boundary along 931 * with the full range of the operation. If we don't, a COW writeback 932 * completion could race with an insert, front merge with the start 933 * extent (after split) during the shift and corrupt the file. Start 934 * with the allocation unit just prior to the start to stabilize the 935 * boundary. 936 */ 937 rounding = xfs_inode_alloc_unitsize(ip); 938 offset = rounddown_64(offset, rounding); 939 if (offset) 940 offset -= rounding; 941 942 /* 943 * Writeback and invalidate cache for the remainder of the file as we're 944 * about to shift down every extent from offset to EOF. 945 */ 946 error = xfs_flush_unmap_range(ip, offset, XFS_ISIZE(ip)); 947 if (error) 948 return error; 949 950 /* 951 * Clean out anything hanging around in the cow fork now that 952 * we've flushed all the dirty data out to disk to avoid having 953 * CoW extents at the wrong offsets. 954 */ 955 if (xfs_inode_has_cow_data(ip)) { 956 error = xfs_reflink_cancel_cow_range(ip, offset, NULLFILEOFF, 957 true); 958 if (error) 959 return error; 960 } 961 962 return 0; 963 } 964 965 /* 966 * xfs_collapse_file_space() 967 * This routine frees disk space and shift extent for the given file. 968 * The first thing we do is to free data blocks in the specified range 969 * by calling xfs_free_file_space(). It would also sync dirty data 970 * and invalidate page cache over the region on which collapse range 971 * is working. And Shift extent records to the left to cover a hole. 972 * RETURNS: 973 * 0 on success 974 * errno on error 975 * 976 */ 977 int 978 xfs_collapse_file_space( 979 struct xfs_inode *ip, 980 xfs_off_t offset, 981 xfs_off_t len) 982 { 983 struct xfs_mount *mp = ip->i_mount; 984 struct xfs_trans *tp; 985 int error; 986 xfs_fileoff_t next_fsb = XFS_B_TO_FSB(mp, offset + len); 987 xfs_fileoff_t shift_fsb = XFS_B_TO_FSB(mp, len); 988 bool done = false; 989 990 xfs_assert_ilocked(ip, XFS_IOLOCK_EXCL | XFS_MMAPLOCK_EXCL); 991 992 trace_xfs_collapse_file_space(ip); 993 994 error = xfs_free_file_space(ip, offset, len); 995 if (error) 996 return error; 997 998 error = xfs_prepare_shift(ip, offset); 999 if (error) 1000 return error; 1001 1002 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, 0, 0, 0, &tp); 1003 if (error) 1004 return error; 1005 1006 xfs_ilock(ip, XFS_ILOCK_EXCL); 1007 xfs_trans_ijoin(tp, ip, 0); 1008 1009 while (!done) { 1010 error = xfs_bmap_collapse_extents(tp, ip, &next_fsb, shift_fsb, 1011 &done); 1012 if (error) 1013 goto out_trans_cancel; 1014 if (done) 1015 break; 1016 1017 /* finish any deferred frees and roll the transaction */ 1018 error = xfs_defer_finish(&tp); 1019 if (error) 1020 goto out_trans_cancel; 1021 } 1022 1023 error = xfs_trans_commit(tp); 1024 xfs_iunlock(ip, XFS_ILOCK_EXCL); 1025 return error; 1026 1027 out_trans_cancel: 1028 xfs_trans_cancel(tp); 1029 xfs_iunlock(ip, XFS_ILOCK_EXCL); 1030 return error; 1031 } 1032 1033 /* 1034 * xfs_insert_file_space() 1035 * This routine create hole space by shifting extents for the given file. 1036 * The first thing we do is to sync dirty data and invalidate page cache 1037 * over the region on which insert range is working. And split an extent 1038 * to two extents at given offset by calling xfs_bmap_split_extent. 1039 * And shift all extent records which are laying between [offset, 1040 * last allocated extent] to the right to reserve hole range. 1041 * RETURNS: 1042 * 0 on success 1043 * errno on error 1044 */ 1045 int 1046 xfs_insert_file_space( 1047 struct xfs_inode *ip, 1048 loff_t offset, 1049 loff_t len) 1050 { 1051 struct xfs_mount *mp = ip->i_mount; 1052 struct xfs_trans *tp; 1053 int error; 1054 xfs_fileoff_t stop_fsb = XFS_B_TO_FSB(mp, offset); 1055 xfs_fileoff_t next_fsb = NULLFSBLOCK; 1056 xfs_fileoff_t shift_fsb = XFS_B_TO_FSB(mp, len); 1057 bool done = false; 1058 1059 xfs_assert_ilocked(ip, XFS_IOLOCK_EXCL | XFS_MMAPLOCK_EXCL); 1060 1061 trace_xfs_insert_file_space(ip); 1062 1063 error = xfs_bmap_can_insert_extents(ip, stop_fsb, shift_fsb); 1064 if (error) 1065 return error; 1066 1067 error = xfs_prepare_shift(ip, offset); 1068 if (error) 1069 return error; 1070 1071 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, 1072 XFS_DIOSTRAT_SPACE_RES(mp, 0), 0, 0, &tp); 1073 if (error) 1074 return error; 1075 1076 xfs_ilock(ip, XFS_ILOCK_EXCL); 1077 xfs_trans_ijoin(tp, ip, 0); 1078 1079 error = xfs_iext_count_extend(tp, ip, XFS_DATA_FORK, 1080 XFS_IEXT_PUNCH_HOLE_CNT); 1081 if (error) 1082 goto out_trans_cancel; 1083 1084 /* 1085 * The extent shifting code works on extent granularity. So, if stop_fsb 1086 * is not the starting block of extent, we need to split the extent at 1087 * stop_fsb. 1088 */ 1089 error = xfs_bmap_split_extent(tp, ip, stop_fsb); 1090 if (error) 1091 goto out_trans_cancel; 1092 1093 do { 1094 error = xfs_defer_finish(&tp); 1095 if (error) 1096 goto out_trans_cancel; 1097 1098 error = xfs_bmap_insert_extents(tp, ip, &next_fsb, shift_fsb, 1099 &done, stop_fsb); 1100 if (error) 1101 goto out_trans_cancel; 1102 } while (!done); 1103 1104 error = xfs_trans_commit(tp); 1105 xfs_iunlock(ip, XFS_ILOCK_EXCL); 1106 return error; 1107 1108 out_trans_cancel: 1109 xfs_trans_cancel(tp); 1110 xfs_iunlock(ip, XFS_ILOCK_EXCL); 1111 return error; 1112 } 1113 1114 /* 1115 * We need to check that the format of the data fork in the temporary inode is 1116 * valid for the target inode before doing the swap. This is not a problem with 1117 * attr1 because of the fixed fork offset, but attr2 has a dynamically sized 1118 * data fork depending on the space the attribute fork is taking so we can get 1119 * invalid formats on the target inode. 1120 * 1121 * E.g. target has space for 7 extents in extent format, temp inode only has 1122 * space for 6. If we defragment down to 7 extents, then the tmp format is a 1123 * btree, but when swapped it needs to be in extent format. Hence we can't just 1124 * blindly swap data forks on attr2 filesystems. 1125 * 1126 * Note that we check the swap in both directions so that we don't end up with 1127 * a corrupt temporary inode, either. 1128 * 1129 * Note that fixing the way xfs_fsr sets up the attribute fork in the source 1130 * inode will prevent this situation from occurring, so all we do here is 1131 * reject and log the attempt. basically we are putting the responsibility on 1132 * userspace to get this right. 1133 */ 1134 static int 1135 xfs_swap_extents_check_format( 1136 struct xfs_inode *ip, /* target inode */ 1137 struct xfs_inode *tip) /* tmp inode */ 1138 { 1139 struct xfs_ifork *ifp = &ip->i_df; 1140 struct xfs_ifork *tifp = &tip->i_df; 1141 1142 /* User/group/project quota ids must match if quotas are enforced. */ 1143 if (XFS_IS_QUOTA_ON(ip->i_mount) && 1144 (!uid_eq(VFS_I(ip)->i_uid, VFS_I(tip)->i_uid) || 1145 !gid_eq(VFS_I(ip)->i_gid, VFS_I(tip)->i_gid) || 1146 ip->i_projid != tip->i_projid)) 1147 return -EINVAL; 1148 1149 /* Should never get a local format */ 1150 if (ifp->if_format == XFS_DINODE_FMT_LOCAL || 1151 tifp->if_format == XFS_DINODE_FMT_LOCAL) 1152 return -EINVAL; 1153 1154 /* 1155 * if the target inode has less extents that then temporary inode then 1156 * why did userspace call us? 1157 */ 1158 if (ifp->if_nextents < tifp->if_nextents) 1159 return -EINVAL; 1160 1161 /* 1162 * If we have to use the (expensive) rmap swap method, we can 1163 * handle any number of extents and any format. 1164 */ 1165 if (xfs_has_rmapbt(ip->i_mount)) 1166 return 0; 1167 1168 /* 1169 * if the target inode is in extent form and the temp inode is in btree 1170 * form then we will end up with the target inode in the wrong format 1171 * as we already know there are less extents in the temp inode. 1172 */ 1173 if (ifp->if_format == XFS_DINODE_FMT_EXTENTS && 1174 tifp->if_format == XFS_DINODE_FMT_BTREE) 1175 return -EINVAL; 1176 1177 /* Check temp in extent form to max in target */ 1178 if (tifp->if_format == XFS_DINODE_FMT_EXTENTS && 1179 tifp->if_nextents > XFS_IFORK_MAXEXT(ip, XFS_DATA_FORK)) 1180 return -EINVAL; 1181 1182 /* Check target in extent form to max in temp */ 1183 if (ifp->if_format == XFS_DINODE_FMT_EXTENTS && 1184 ifp->if_nextents > XFS_IFORK_MAXEXT(tip, XFS_DATA_FORK)) 1185 return -EINVAL; 1186 1187 /* 1188 * If we are in a btree format, check that the temp root block will fit 1189 * in the target and that it has enough extents to be in btree format 1190 * in the target. 1191 * 1192 * Note that we have to be careful to allow btree->extent conversions 1193 * (a common defrag case) which will occur when the temp inode is in 1194 * extent format... 1195 */ 1196 if (tifp->if_format == XFS_DINODE_FMT_BTREE) { 1197 if (xfs_inode_has_attr_fork(ip) && 1198 XFS_BMAP_BMDR_SPACE(tifp->if_broot) > xfs_inode_fork_boff(ip)) 1199 return -EINVAL; 1200 if (tifp->if_nextents <= XFS_IFORK_MAXEXT(ip, XFS_DATA_FORK)) 1201 return -EINVAL; 1202 } 1203 1204 /* Reciprocal target->temp btree format checks */ 1205 if (ifp->if_format == XFS_DINODE_FMT_BTREE) { 1206 if (xfs_inode_has_attr_fork(tip) && 1207 XFS_BMAP_BMDR_SPACE(ip->i_df.if_broot) > xfs_inode_fork_boff(tip)) 1208 return -EINVAL; 1209 if (ifp->if_nextents <= XFS_IFORK_MAXEXT(tip, XFS_DATA_FORK)) 1210 return -EINVAL; 1211 } 1212 1213 return 0; 1214 } 1215 1216 static int 1217 xfs_swap_extent_flush( 1218 struct xfs_inode *ip) 1219 { 1220 int error; 1221 1222 error = filemap_write_and_wait(VFS_I(ip)->i_mapping); 1223 if (error) 1224 return error; 1225 truncate_pagecache_range(VFS_I(ip), 0, -1); 1226 1227 /* Verify O_DIRECT for ftmp */ 1228 if (VFS_I(ip)->i_mapping->nrpages) 1229 return -EINVAL; 1230 return 0; 1231 } 1232 1233 /* 1234 * Move extents from one file to another, when rmap is enabled. 1235 */ 1236 STATIC int 1237 xfs_swap_extent_rmap( 1238 struct xfs_trans **tpp, 1239 struct xfs_inode *ip, 1240 struct xfs_inode *tip) 1241 { 1242 struct xfs_trans *tp = *tpp; 1243 struct xfs_bmbt_irec irec; 1244 struct xfs_bmbt_irec uirec; 1245 struct xfs_bmbt_irec tirec; 1246 xfs_fileoff_t offset_fsb; 1247 xfs_fileoff_t end_fsb; 1248 xfs_filblks_t count_fsb; 1249 int error; 1250 xfs_filblks_t ilen; 1251 xfs_filblks_t rlen; 1252 int nimaps; 1253 uint64_t tip_flags2; 1254 1255 /* 1256 * If the source file has shared blocks, we must flag the donor 1257 * file as having shared blocks so that we get the shared-block 1258 * rmap functions when we go to fix up the rmaps. The flags 1259 * will be switch for reals later. 1260 */ 1261 tip_flags2 = tip->i_diflags2; 1262 if (ip->i_diflags2 & XFS_DIFLAG2_REFLINK) 1263 tip->i_diflags2 |= XFS_DIFLAG2_REFLINK; 1264 1265 offset_fsb = 0; 1266 end_fsb = XFS_B_TO_FSB(ip->i_mount, i_size_read(VFS_I(ip))); 1267 count_fsb = (xfs_filblks_t)(end_fsb - offset_fsb); 1268 1269 while (count_fsb) { 1270 /* Read extent from the donor file */ 1271 nimaps = 1; 1272 error = xfs_bmapi_read(tip, offset_fsb, count_fsb, &tirec, 1273 &nimaps, 0); 1274 if (error) 1275 goto out; 1276 ASSERT(nimaps == 1); 1277 ASSERT(tirec.br_startblock != DELAYSTARTBLOCK); 1278 1279 trace_xfs_swap_extent_rmap_remap(tip, &tirec); 1280 ilen = tirec.br_blockcount; 1281 1282 /* Unmap the old blocks in the source file. */ 1283 while (tirec.br_blockcount) { 1284 ASSERT(tp->t_highest_agno == NULLAGNUMBER); 1285 trace_xfs_swap_extent_rmap_remap_piece(tip, &tirec); 1286 1287 /* Read extent from the source file */ 1288 nimaps = 1; 1289 error = xfs_bmapi_read(ip, tirec.br_startoff, 1290 tirec.br_blockcount, &irec, 1291 &nimaps, 0); 1292 if (error) 1293 goto out; 1294 ASSERT(nimaps == 1); 1295 ASSERT(tirec.br_startoff == irec.br_startoff); 1296 trace_xfs_swap_extent_rmap_remap_piece(ip, &irec); 1297 1298 /* Trim the extent. */ 1299 uirec = tirec; 1300 uirec.br_blockcount = rlen = min_t(xfs_filblks_t, 1301 tirec.br_blockcount, 1302 irec.br_blockcount); 1303 trace_xfs_swap_extent_rmap_remap_piece(tip, &uirec); 1304 1305 if (xfs_bmap_is_real_extent(&uirec)) { 1306 error = xfs_iext_count_extend(tp, ip, 1307 XFS_DATA_FORK, 1308 XFS_IEXT_SWAP_RMAP_CNT); 1309 if (error) 1310 goto out; 1311 } 1312 1313 if (xfs_bmap_is_real_extent(&irec)) { 1314 error = xfs_iext_count_extend(tp, tip, 1315 XFS_DATA_FORK, 1316 XFS_IEXT_SWAP_RMAP_CNT); 1317 if (error) 1318 goto out; 1319 } 1320 1321 /* Remove the mapping from the donor file. */ 1322 xfs_bmap_unmap_extent(tp, tip, XFS_DATA_FORK, &uirec); 1323 1324 /* Remove the mapping from the source file. */ 1325 xfs_bmap_unmap_extent(tp, ip, XFS_DATA_FORK, &irec); 1326 1327 /* Map the donor file's blocks into the source file. */ 1328 xfs_bmap_map_extent(tp, ip, XFS_DATA_FORK, &uirec); 1329 1330 /* Map the source file's blocks into the donor file. */ 1331 xfs_bmap_map_extent(tp, tip, XFS_DATA_FORK, &irec); 1332 1333 error = xfs_defer_finish(tpp); 1334 tp = *tpp; 1335 if (error) 1336 goto out; 1337 1338 tirec.br_startoff += rlen; 1339 if (tirec.br_startblock != HOLESTARTBLOCK && 1340 tirec.br_startblock != DELAYSTARTBLOCK) 1341 tirec.br_startblock += rlen; 1342 tirec.br_blockcount -= rlen; 1343 } 1344 1345 /* Roll on... */ 1346 count_fsb -= ilen; 1347 offset_fsb += ilen; 1348 } 1349 1350 tip->i_diflags2 = tip_flags2; 1351 return 0; 1352 1353 out: 1354 trace_xfs_swap_extent_rmap_error(ip, error, _RET_IP_); 1355 tip->i_diflags2 = tip_flags2; 1356 return error; 1357 } 1358 1359 /* Swap the extents of two files by swapping data forks. */ 1360 STATIC int 1361 xfs_swap_extent_forks( 1362 struct xfs_trans *tp, 1363 struct xfs_inode *ip, 1364 struct xfs_inode *tip, 1365 int *src_log_flags, 1366 int *target_log_flags) 1367 { 1368 xfs_filblks_t aforkblks = 0; 1369 xfs_filblks_t taforkblks = 0; 1370 xfs_extnum_t junk; 1371 uint64_t tmp; 1372 int error; 1373 1374 /* 1375 * Count the number of extended attribute blocks 1376 */ 1377 if (xfs_inode_has_attr_fork(ip) && ip->i_af.if_nextents > 0 && 1378 ip->i_af.if_format != XFS_DINODE_FMT_LOCAL) { 1379 error = xfs_bmap_count_blocks(tp, ip, XFS_ATTR_FORK, &junk, 1380 &aforkblks); 1381 if (error) 1382 return error; 1383 } 1384 if (xfs_inode_has_attr_fork(tip) && tip->i_af.if_nextents > 0 && 1385 tip->i_af.if_format != XFS_DINODE_FMT_LOCAL) { 1386 error = xfs_bmap_count_blocks(tp, tip, XFS_ATTR_FORK, &junk, 1387 &taforkblks); 1388 if (error) 1389 return error; 1390 } 1391 1392 /* 1393 * Btree format (v3) inodes have the inode number stamped in the bmbt 1394 * block headers. We can't start changing the bmbt blocks until the 1395 * inode owner change is logged so recovery does the right thing in the 1396 * event of a crash. Set the owner change log flags now and leave the 1397 * bmbt scan as the last step. 1398 */ 1399 if (xfs_has_v3inodes(ip->i_mount)) { 1400 if (ip->i_df.if_format == XFS_DINODE_FMT_BTREE) 1401 (*target_log_flags) |= XFS_ILOG_DOWNER; 1402 if (tip->i_df.if_format == XFS_DINODE_FMT_BTREE) 1403 (*src_log_flags) |= XFS_ILOG_DOWNER; 1404 } 1405 1406 /* 1407 * Swap the data forks of the inodes 1408 */ 1409 swap(ip->i_df, tip->i_df); 1410 1411 /* 1412 * Fix the on-disk inode values 1413 */ 1414 tmp = (uint64_t)ip->i_nblocks; 1415 ip->i_nblocks = tip->i_nblocks - taforkblks + aforkblks; 1416 tip->i_nblocks = tmp + taforkblks - aforkblks; 1417 1418 /* 1419 * The extents in the source inode could still contain speculative 1420 * preallocation beyond EOF (e.g. the file is open but not modified 1421 * while defrag is in progress). In that case, we need to copy over the 1422 * number of delalloc blocks the data fork in the source inode is 1423 * tracking beyond EOF so that when the fork is truncated away when the 1424 * temporary inode is unlinked we don't underrun the i_delayed_blks 1425 * counter on that inode. 1426 */ 1427 ASSERT(tip->i_delayed_blks == 0); 1428 tip->i_delayed_blks = ip->i_delayed_blks; 1429 ip->i_delayed_blks = 0; 1430 1431 switch (ip->i_df.if_format) { 1432 case XFS_DINODE_FMT_EXTENTS: 1433 (*src_log_flags) |= XFS_ILOG_DEXT; 1434 break; 1435 case XFS_DINODE_FMT_BTREE: 1436 ASSERT(!xfs_has_v3inodes(ip->i_mount) || 1437 (*src_log_flags & XFS_ILOG_DOWNER)); 1438 (*src_log_flags) |= XFS_ILOG_DBROOT; 1439 break; 1440 } 1441 1442 switch (tip->i_df.if_format) { 1443 case XFS_DINODE_FMT_EXTENTS: 1444 (*target_log_flags) |= XFS_ILOG_DEXT; 1445 break; 1446 case XFS_DINODE_FMT_BTREE: 1447 (*target_log_flags) |= XFS_ILOG_DBROOT; 1448 ASSERT(!xfs_has_v3inodes(ip->i_mount) || 1449 (*target_log_flags & XFS_ILOG_DOWNER)); 1450 break; 1451 } 1452 1453 return 0; 1454 } 1455 1456 /* 1457 * Fix up the owners of the bmbt blocks to refer to the current inode. The 1458 * change owner scan attempts to order all modified buffers in the current 1459 * transaction. In the event of ordered buffer failure, the offending buffer is 1460 * physically logged as a fallback and the scan returns -EAGAIN. We must roll 1461 * the transaction in this case to replenish the fallback log reservation and 1462 * restart the scan. This process repeats until the scan completes. 1463 */ 1464 static int 1465 xfs_swap_change_owner( 1466 struct xfs_trans **tpp, 1467 struct xfs_inode *ip, 1468 struct xfs_inode *tmpip) 1469 { 1470 int error; 1471 struct xfs_trans *tp = *tpp; 1472 1473 do { 1474 error = xfs_bmbt_change_owner(tp, ip, XFS_DATA_FORK, ip->i_ino, 1475 NULL); 1476 /* success or fatal error */ 1477 if (error != -EAGAIN) 1478 break; 1479 1480 error = xfs_trans_roll(tpp); 1481 if (error) 1482 break; 1483 tp = *tpp; 1484 1485 /* 1486 * Redirty both inodes so they can relog and keep the log tail 1487 * moving forward. 1488 */ 1489 xfs_trans_ijoin(tp, ip, 0); 1490 xfs_trans_ijoin(tp, tmpip, 0); 1491 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE); 1492 xfs_trans_log_inode(tp, tmpip, XFS_ILOG_CORE); 1493 } while (true); 1494 1495 return error; 1496 } 1497 1498 int 1499 xfs_swap_extents( 1500 struct xfs_inode *ip, /* target inode */ 1501 struct xfs_inode *tip, /* tmp inode */ 1502 struct xfs_swapext *sxp) 1503 { 1504 struct xfs_mount *mp = ip->i_mount; 1505 struct xfs_trans *tp; 1506 struct xfs_bstat *sbp = &sxp->sx_stat; 1507 int src_log_flags, target_log_flags; 1508 int error = 0; 1509 uint64_t f; 1510 int resblks = 0; 1511 unsigned int flags = 0; 1512 struct timespec64 ctime, mtime; 1513 1514 /* 1515 * Lock the inodes against other IO, page faults and truncate to 1516 * begin with. Then we can ensure the inodes are flushed and have no 1517 * page cache safely. Once we have done this we can take the ilocks and 1518 * do the rest of the checks. 1519 */ 1520 lock_two_nondirectories(VFS_I(ip), VFS_I(tip)); 1521 filemap_invalidate_lock_two(VFS_I(ip)->i_mapping, 1522 VFS_I(tip)->i_mapping); 1523 1524 /* Verify that both files have the same format */ 1525 if ((VFS_I(ip)->i_mode & S_IFMT) != (VFS_I(tip)->i_mode & S_IFMT)) { 1526 error = -EINVAL; 1527 goto out_unlock; 1528 } 1529 1530 /* Verify both files are either real-time or non-realtime */ 1531 if (XFS_IS_REALTIME_INODE(ip) != XFS_IS_REALTIME_INODE(tip)) { 1532 error = -EINVAL; 1533 goto out_unlock; 1534 } 1535 1536 error = xfs_qm_dqattach(ip); 1537 if (error) 1538 goto out_unlock; 1539 1540 error = xfs_qm_dqattach(tip); 1541 if (error) 1542 goto out_unlock; 1543 1544 error = xfs_swap_extent_flush(ip); 1545 if (error) 1546 goto out_unlock; 1547 error = xfs_swap_extent_flush(tip); 1548 if (error) 1549 goto out_unlock; 1550 1551 if (xfs_inode_has_cow_data(tip)) { 1552 error = xfs_reflink_cancel_cow_range(tip, 0, NULLFILEOFF, true); 1553 if (error) 1554 goto out_unlock; 1555 } 1556 1557 /* 1558 * Extent "swapping" with rmap requires a permanent reservation and 1559 * a block reservation because it's really just a remap operation 1560 * performed with log redo items! 1561 */ 1562 if (xfs_has_rmapbt(mp)) { 1563 int w = XFS_DATA_FORK; 1564 uint32_t ipnext = ip->i_df.if_nextents; 1565 uint32_t tipnext = tip->i_df.if_nextents; 1566 1567 /* 1568 * Conceptually this shouldn't affect the shape of either bmbt, 1569 * but since we atomically move extents one by one, we reserve 1570 * enough space to rebuild both trees. 1571 */ 1572 resblks = XFS_SWAP_RMAP_SPACE_RES(mp, ipnext, w); 1573 resblks += XFS_SWAP_RMAP_SPACE_RES(mp, tipnext, w); 1574 1575 /* 1576 * If either inode straddles a bmapbt block allocation boundary, 1577 * the rmapbt algorithm triggers repeated allocs and frees as 1578 * extents are remapped. This can exhaust the block reservation 1579 * prematurely and cause shutdown. Return freed blocks to the 1580 * transaction reservation to counter this behavior. 1581 */ 1582 flags |= XFS_TRANS_RES_FDBLKS; 1583 } 1584 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, resblks, 0, flags, 1585 &tp); 1586 if (error) 1587 goto out_unlock; 1588 1589 /* 1590 * Lock and join the inodes to the tansaction so that transaction commit 1591 * or cancel will unlock the inodes from this point onwards. 1592 */ 1593 xfs_lock_two_inodes(ip, XFS_ILOCK_EXCL, tip, XFS_ILOCK_EXCL); 1594 xfs_trans_ijoin(tp, ip, 0); 1595 xfs_trans_ijoin(tp, tip, 0); 1596 1597 1598 /* Verify all data are being swapped */ 1599 if (sxp->sx_offset != 0 || 1600 sxp->sx_length != ip->i_disk_size || 1601 sxp->sx_length != tip->i_disk_size) { 1602 error = -EFAULT; 1603 goto out_trans_cancel; 1604 } 1605 1606 trace_xfs_swap_extent_before(ip, 0); 1607 trace_xfs_swap_extent_before(tip, 1); 1608 1609 /* check inode formats now that data is flushed */ 1610 error = xfs_swap_extents_check_format(ip, tip); 1611 if (error) { 1612 xfs_notice(mp, 1613 "%s: inode 0x%llx format is incompatible for exchanging.", 1614 __func__, ip->i_ino); 1615 goto out_trans_cancel; 1616 } 1617 1618 /* 1619 * Compare the current change & modify times with that 1620 * passed in. If they differ, we abort this swap. 1621 * This is the mechanism used to ensure the calling 1622 * process that the file was not changed out from 1623 * under it. 1624 */ 1625 ctime = inode_get_ctime(VFS_I(ip)); 1626 mtime = inode_get_mtime(VFS_I(ip)); 1627 if ((sbp->bs_ctime.tv_sec != ctime.tv_sec) || 1628 (sbp->bs_ctime.tv_nsec != ctime.tv_nsec) || 1629 (sbp->bs_mtime.tv_sec != mtime.tv_sec) || 1630 (sbp->bs_mtime.tv_nsec != mtime.tv_nsec)) { 1631 error = -EBUSY; 1632 goto out_trans_cancel; 1633 } 1634 1635 /* 1636 * Note the trickiness in setting the log flags - we set the owner log 1637 * flag on the opposite inode (i.e. the inode we are setting the new 1638 * owner to be) because once we swap the forks and log that, log 1639 * recovery is going to see the fork as owned by the swapped inode, 1640 * not the pre-swapped inodes. 1641 */ 1642 src_log_flags = XFS_ILOG_CORE; 1643 target_log_flags = XFS_ILOG_CORE; 1644 1645 if (xfs_has_rmapbt(mp)) 1646 error = xfs_swap_extent_rmap(&tp, ip, tip); 1647 else 1648 error = xfs_swap_extent_forks(tp, ip, tip, &src_log_flags, 1649 &target_log_flags); 1650 if (error) 1651 goto out_trans_cancel; 1652 1653 /* Do we have to swap reflink flags? */ 1654 if ((ip->i_diflags2 & XFS_DIFLAG2_REFLINK) ^ 1655 (tip->i_diflags2 & XFS_DIFLAG2_REFLINK)) { 1656 f = ip->i_diflags2 & XFS_DIFLAG2_REFLINK; 1657 ip->i_diflags2 &= ~XFS_DIFLAG2_REFLINK; 1658 ip->i_diflags2 |= tip->i_diflags2 & XFS_DIFLAG2_REFLINK; 1659 tip->i_diflags2 &= ~XFS_DIFLAG2_REFLINK; 1660 tip->i_diflags2 |= f & XFS_DIFLAG2_REFLINK; 1661 } 1662 1663 /* Swap the cow forks. */ 1664 if (xfs_has_reflink(mp)) { 1665 ASSERT(!ip->i_cowfp || 1666 ip->i_cowfp->if_format == XFS_DINODE_FMT_EXTENTS); 1667 ASSERT(!tip->i_cowfp || 1668 tip->i_cowfp->if_format == XFS_DINODE_FMT_EXTENTS); 1669 1670 swap(ip->i_cowfp, tip->i_cowfp); 1671 1672 if (ip->i_cowfp && ip->i_cowfp->if_bytes) 1673 xfs_inode_set_cowblocks_tag(ip); 1674 else 1675 xfs_inode_clear_cowblocks_tag(ip); 1676 if (tip->i_cowfp && tip->i_cowfp->if_bytes) 1677 xfs_inode_set_cowblocks_tag(tip); 1678 else 1679 xfs_inode_clear_cowblocks_tag(tip); 1680 } 1681 1682 xfs_trans_log_inode(tp, ip, src_log_flags); 1683 xfs_trans_log_inode(tp, tip, target_log_flags); 1684 1685 /* 1686 * The extent forks have been swapped, but crc=1,rmapbt=0 filesystems 1687 * have inode number owner values in the bmbt blocks that still refer to 1688 * the old inode. Scan each bmbt to fix up the owner values with the 1689 * inode number of the current inode. 1690 */ 1691 if (src_log_flags & XFS_ILOG_DOWNER) { 1692 error = xfs_swap_change_owner(&tp, ip, tip); 1693 if (error) 1694 goto out_trans_cancel; 1695 } 1696 if (target_log_flags & XFS_ILOG_DOWNER) { 1697 error = xfs_swap_change_owner(&tp, tip, ip); 1698 if (error) 1699 goto out_trans_cancel; 1700 } 1701 1702 /* 1703 * If this is a synchronous mount, make sure that the 1704 * transaction goes to disk before returning to the user. 1705 */ 1706 if (xfs_has_wsync(mp)) 1707 xfs_trans_set_sync(tp); 1708 1709 error = xfs_trans_commit(tp); 1710 1711 trace_xfs_swap_extent_after(ip, 0); 1712 trace_xfs_swap_extent_after(tip, 1); 1713 1714 out_unlock_ilock: 1715 xfs_iunlock(ip, XFS_ILOCK_EXCL); 1716 xfs_iunlock(tip, XFS_ILOCK_EXCL); 1717 out_unlock: 1718 filemap_invalidate_unlock_two(VFS_I(ip)->i_mapping, 1719 VFS_I(tip)->i_mapping); 1720 unlock_two_nondirectories(VFS_I(ip), VFS_I(tip)); 1721 return error; 1722 1723 out_trans_cancel: 1724 xfs_trans_cancel(tp); 1725 goto out_unlock_ilock; 1726 } 1727