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 & XFS_DIFLAG_PREALLOC)) 335 max_len = mp->m_super->s_maxbytes; 336 else 337 max_len = XFS_ISIZE(ip); 338 339 lock = xfs_ilock_data_map_shared(ip); 340 break; 341 } 342 343 ifp = xfs_ifork_ptr(ip, whichfork); 344 345 switch (ifp->if_format) { 346 case XFS_DINODE_FMT_EXTENTS: 347 case XFS_DINODE_FMT_BTREE: 348 break; 349 case XFS_DINODE_FMT_LOCAL: 350 /* Local format inode forks report no extents. */ 351 goto out_unlock_ilock; 352 default: 353 error = -EINVAL; 354 goto out_unlock_ilock; 355 } 356 357 if (bmv->bmv_length == -1) { 358 max_len = XFS_FSB_TO_BB(mp, XFS_B_TO_FSB(mp, max_len)); 359 bmv->bmv_length = max(0LL, max_len - bmv->bmv_offset); 360 } 361 362 bmv_end = bmv->bmv_offset + bmv->bmv_length; 363 364 first_bno = bno = XFS_BB_TO_FSBT(mp, bmv->bmv_offset); 365 len = XFS_BB_TO_FSB(mp, bmv->bmv_length); 366 367 error = xfs_iread_extents(NULL, ip, whichfork); 368 if (error) 369 goto out_unlock_ilock; 370 371 if (!xfs_iext_lookup_extent(ip, ifp, bno, &icur, &got)) { 372 /* 373 * Report a whole-file hole if the delalloc flag is set to 374 * stay compatible with the old implementation. 375 */ 376 if (iflags & BMV_IF_DELALLOC) 377 xfs_getbmap_report_hole(ip, bmv, out, bmv_end, bno, 378 XFS_B_TO_FSB(mp, XFS_ISIZE(ip))); 379 goto out_unlock_ilock; 380 } 381 382 while (!xfs_getbmap_full(bmv)) { 383 xfs_trim_extent(&got, first_bno, len); 384 385 /* 386 * Report an entry for a hole if this extent doesn't directly 387 * follow the previous one. 388 */ 389 if (got.br_startoff > bno) { 390 xfs_getbmap_report_hole(ip, bmv, out, bmv_end, bno, 391 got.br_startoff); 392 if (xfs_getbmap_full(bmv)) 393 break; 394 } 395 396 /* 397 * In order to report shared extents accurately, we report each 398 * distinct shared / unshared part of a single bmbt record with 399 * an individual getbmapx record. 400 */ 401 bno = got.br_startoff + got.br_blockcount; 402 rec = got; 403 do { 404 error = xfs_getbmap_report_one(ip, bmv, out, bmv_end, 405 &rec); 406 if (error || xfs_getbmap_full(bmv)) 407 goto out_unlock_ilock; 408 } while (xfs_getbmap_next_rec(&rec, bno)); 409 410 if (!xfs_iext_next_extent(ifp, &icur, &got)) { 411 xfs_fileoff_t end = XFS_B_TO_FSB(mp, XFS_ISIZE(ip)); 412 413 if (bmv->bmv_entries > 0) 414 out[bmv->bmv_entries - 1].bmv_oflags |= 415 BMV_OF_LAST; 416 417 if (whichfork != XFS_ATTR_FORK && bno < end && 418 !xfs_getbmap_full(bmv)) { 419 xfs_getbmap_report_hole(ip, bmv, out, bmv_end, 420 bno, end); 421 } 422 break; 423 } 424 425 if (bno >= first_bno + len) 426 break; 427 } 428 429 out_unlock_ilock: 430 xfs_iunlock(ip, lock); 431 out_unlock_iolock: 432 xfs_iunlock(ip, XFS_IOLOCK_SHARED); 433 return error; 434 } 435 436 /* 437 * Dead simple method of punching delalyed allocation blocks from a range in 438 * the inode. This will always punch out both the start and end blocks, even 439 * if the ranges only partially overlap them, so it is up to the caller to 440 * ensure that partial blocks are not passed in. 441 */ 442 void 443 xfs_bmap_punch_delalloc_range( 444 struct xfs_inode *ip, 445 int whichfork, 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 = xfs_ifork_ptr(ip, whichfork); 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, whichfork, &icur, &got, &del); 479 if (!xfs_iext_get_extent(ifp, &icur, &got)) 480 break; 481 } 482 483 if (whichfork == XFS_COW_FORK && !ifp->if_bytes) 484 xfs_inode_clear_cowblocks_tag(ip); 485 486 out_unlock: 487 xfs_iunlock(ip, XFS_ILOCK_EXCL); 488 } 489 490 /* 491 * Test whether it is appropriate to check an inode for and free post EOF 492 * blocks. 493 */ 494 bool 495 xfs_can_free_eofblocks( 496 struct xfs_inode *ip) 497 { 498 struct xfs_mount *mp = ip->i_mount; 499 bool found_blocks = false; 500 xfs_fileoff_t end_fsb; 501 xfs_fileoff_t last_fsb; 502 struct xfs_bmbt_irec imap; 503 struct xfs_iext_cursor icur; 504 505 /* 506 * Caller must either hold the exclusive io lock; or be inactivating 507 * the inode, which guarantees there are no other users of the inode. 508 */ 509 if (!(VFS_I(ip)->i_state & I_FREEING)) 510 xfs_assert_ilocked(ip, XFS_IOLOCK_EXCL); 511 512 /* prealloc/delalloc exists only on regular files */ 513 if (!S_ISREG(VFS_I(ip)->i_mode)) 514 return false; 515 516 /* 517 * Zero sized files with no cached pages and delalloc blocks will not 518 * have speculative prealloc/delalloc blocks to remove. 519 */ 520 if (VFS_I(ip)->i_size == 0 && 521 VFS_I(ip)->i_mapping->nrpages == 0 && 522 ip->i_delayed_blks == 0) 523 return false; 524 525 /* If we haven't read in the extent list, then don't do it now. */ 526 if (xfs_need_iread_extents(&ip->i_df)) 527 return false; 528 529 /* 530 * Do not free real extents in preallocated files unless the file has 531 * delalloc blocks and we are forced to remove them. 532 */ 533 if ((ip->i_diflags & XFS_DIFLAG_PREALLOC) && !ip->i_delayed_blks) 534 return false; 535 536 /* 537 * Do not try to free post-EOF blocks if EOF is beyond the end of the 538 * range supported by the page cache, because the truncation will loop 539 * forever. 540 */ 541 end_fsb = XFS_B_TO_FSB(mp, (xfs_ufsize_t)XFS_ISIZE(ip)); 542 if (xfs_inode_has_bigrtalloc(ip)) 543 end_fsb = xfs_rtb_roundup_rtx(mp, end_fsb); 544 last_fsb = XFS_B_TO_FSB(mp, mp->m_super->s_maxbytes); 545 if (last_fsb <= end_fsb) 546 return false; 547 548 /* 549 * Check if there is an post-EOF extent to free. 550 */ 551 xfs_ilock(ip, XFS_ILOCK_SHARED); 552 if (xfs_iext_lookup_extent(ip, &ip->i_df, end_fsb, &icur, &imap)) 553 found_blocks = true; 554 xfs_iunlock(ip, XFS_ILOCK_SHARED); 555 return found_blocks; 556 } 557 558 /* 559 * This is called to free any blocks beyond eof. The caller must hold 560 * IOLOCK_EXCL unless we are in the inode reclaim path and have the only 561 * reference to the inode. 562 */ 563 int 564 xfs_free_eofblocks( 565 struct xfs_inode *ip) 566 { 567 struct xfs_trans *tp; 568 struct xfs_mount *mp = ip->i_mount; 569 int error; 570 571 /* Attach the dquots to the inode up front. */ 572 error = xfs_qm_dqattach(ip); 573 if (error) 574 return error; 575 576 /* Wait on dio to ensure i_size has settled. */ 577 inode_dio_wait(VFS_I(ip)); 578 579 /* 580 * For preallocated files only free delayed allocations. 581 * 582 * Note that this means we also leave speculative preallocations in 583 * place for preallocated files. 584 */ 585 if (ip->i_diflags & (XFS_DIFLAG_PREALLOC | XFS_DIFLAG_APPEND)) { 586 if (ip->i_delayed_blks) { 587 xfs_bmap_punch_delalloc_range(ip, XFS_DATA_FORK, 588 round_up(XFS_ISIZE(ip), mp->m_sb.sb_blocksize), 589 LLONG_MAX); 590 } 591 xfs_inode_clear_eofblocks_tag(ip); 592 return 0; 593 } 594 595 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_itruncate, 0, 0, 0, &tp); 596 if (error) { 597 ASSERT(xfs_is_shutdown(mp)); 598 return error; 599 } 600 601 xfs_ilock(ip, XFS_ILOCK_EXCL); 602 xfs_trans_ijoin(tp, ip, 0); 603 604 /* 605 * Do not update the on-disk file size. If we update the on-disk file 606 * size and then the system crashes before the contents of the file are 607 * flushed to disk then the files may be full of holes (ie NULL files 608 * bug). 609 */ 610 error = xfs_itruncate_extents_flags(&tp, ip, XFS_DATA_FORK, 611 XFS_ISIZE(ip), XFS_BMAPI_NODISCARD); 612 if (error) 613 goto err_cancel; 614 615 error = xfs_trans_commit(tp); 616 if (error) 617 goto out_unlock; 618 619 xfs_inode_clear_eofblocks_tag(ip); 620 goto out_unlock; 621 622 err_cancel: 623 /* 624 * If we get an error at this point we simply don't 625 * bother truncating the file. 626 */ 627 xfs_trans_cancel(tp); 628 out_unlock: 629 xfs_iunlock(ip, XFS_ILOCK_EXCL); 630 return error; 631 } 632 633 int 634 xfs_alloc_file_space( 635 struct xfs_inode *ip, 636 xfs_off_t offset, 637 xfs_off_t len) 638 { 639 xfs_mount_t *mp = ip->i_mount; 640 xfs_off_t count; 641 xfs_filblks_t allocatesize_fsb; 642 xfs_extlen_t extsz, temp; 643 xfs_fileoff_t startoffset_fsb; 644 xfs_fileoff_t endoffset_fsb; 645 int rt; 646 xfs_trans_t *tp; 647 xfs_bmbt_irec_t imaps[1], *imapp; 648 int error; 649 650 if (xfs_is_always_cow_inode(ip)) 651 return 0; 652 653 trace_xfs_alloc_file_space(ip); 654 655 if (xfs_is_shutdown(mp)) 656 return -EIO; 657 658 error = xfs_qm_dqattach(ip); 659 if (error) 660 return error; 661 662 if (len <= 0) 663 return -EINVAL; 664 665 rt = XFS_IS_REALTIME_INODE(ip); 666 extsz = xfs_get_extsz_hint(ip); 667 668 count = len; 669 imapp = &imaps[0]; 670 startoffset_fsb = XFS_B_TO_FSBT(mp, offset); 671 endoffset_fsb = XFS_B_TO_FSB(mp, offset + count); 672 allocatesize_fsb = endoffset_fsb - startoffset_fsb; 673 674 /* 675 * Allocate file space until done or until there is an error 676 */ 677 while (allocatesize_fsb && !error) { 678 xfs_fileoff_t s, e; 679 unsigned int dblocks, rblocks, resblks; 680 int nimaps = 1; 681 682 /* 683 * Determine space reservations for data/realtime. 684 */ 685 if (unlikely(extsz)) { 686 s = startoffset_fsb; 687 do_div(s, extsz); 688 s *= extsz; 689 e = startoffset_fsb + allocatesize_fsb; 690 div_u64_rem(startoffset_fsb, extsz, &temp); 691 if (temp) 692 e += temp; 693 div_u64_rem(e, extsz, &temp); 694 if (temp) 695 e += extsz - temp; 696 } else { 697 s = 0; 698 e = allocatesize_fsb; 699 } 700 701 /* 702 * The transaction reservation is limited to a 32-bit block 703 * count, hence we need to limit the number of blocks we are 704 * trying to reserve to avoid an overflow. We can't allocate 705 * more than @nimaps extents, and an extent is limited on disk 706 * to XFS_BMBT_MAX_EXTLEN (21 bits), so use that to enforce the 707 * limit. 708 */ 709 resblks = min_t(xfs_fileoff_t, (e - s), 710 (XFS_MAX_BMBT_EXTLEN * nimaps)); 711 if (unlikely(rt)) { 712 dblocks = XFS_DIOSTRAT_SPACE_RES(mp, 0); 713 rblocks = resblks; 714 } else { 715 dblocks = XFS_DIOSTRAT_SPACE_RES(mp, resblks); 716 rblocks = 0; 717 } 718 719 error = xfs_trans_alloc_inode(ip, &M_RES(mp)->tr_write, 720 dblocks, rblocks, false, &tp); 721 if (error) 722 break; 723 724 error = xfs_iext_count_extend(tp, ip, XFS_DATA_FORK, 725 XFS_IEXT_ADD_NOSPLIT_CNT); 726 if (error) 727 goto error; 728 729 /* 730 * If the allocator cannot find a single free extent large 731 * enough to cover the start block of the requested range, 732 * xfs_bmapi_write will return -ENOSR. 733 * 734 * In that case we simply need to keep looping with the same 735 * startoffset_fsb so that one of the following allocations 736 * will eventually reach the requested range. 737 */ 738 error = xfs_bmapi_write(tp, ip, startoffset_fsb, 739 allocatesize_fsb, XFS_BMAPI_PREALLOC, 0, imapp, 740 &nimaps); 741 if (error) { 742 if (error != -ENOSR) 743 goto error; 744 error = 0; 745 } else { 746 startoffset_fsb += imapp->br_blockcount; 747 allocatesize_fsb -= imapp->br_blockcount; 748 } 749 750 ip->i_diflags |= XFS_DIFLAG_PREALLOC; 751 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE); 752 753 error = xfs_trans_commit(tp); 754 xfs_iunlock(ip, XFS_ILOCK_EXCL); 755 } 756 757 return error; 758 759 error: 760 xfs_trans_cancel(tp); 761 xfs_iunlock(ip, XFS_ILOCK_EXCL); 762 return error; 763 } 764 765 static int 766 xfs_unmap_extent( 767 struct xfs_inode *ip, 768 xfs_fileoff_t startoffset_fsb, 769 xfs_filblks_t len_fsb, 770 int *done) 771 { 772 struct xfs_mount *mp = ip->i_mount; 773 struct xfs_trans *tp; 774 uint resblks = XFS_DIOSTRAT_SPACE_RES(mp, 0); 775 int error; 776 777 error = xfs_trans_alloc_inode(ip, &M_RES(mp)->tr_write, resblks, 0, 778 false, &tp); 779 if (error) 780 return error; 781 782 error = xfs_iext_count_extend(tp, ip, XFS_DATA_FORK, 783 XFS_IEXT_PUNCH_HOLE_CNT); 784 if (error) 785 goto out_trans_cancel; 786 787 error = xfs_bunmapi(tp, ip, startoffset_fsb, len_fsb, 0, 2, done); 788 if (error) 789 goto out_trans_cancel; 790 791 error = xfs_trans_commit(tp); 792 out_unlock: 793 xfs_iunlock(ip, XFS_ILOCK_EXCL); 794 return error; 795 796 out_trans_cancel: 797 xfs_trans_cancel(tp); 798 goto out_unlock; 799 } 800 801 /* Caller must first wait for the completion of any pending DIOs if required. */ 802 int 803 xfs_flush_unmap_range( 804 struct xfs_inode *ip, 805 xfs_off_t offset, 806 xfs_off_t len) 807 { 808 struct inode *inode = VFS_I(ip); 809 xfs_off_t rounding, start, end; 810 int error; 811 812 /* 813 * Make sure we extend the flush out to extent alignment 814 * boundaries so any extent range overlapping the start/end 815 * of the modification we are about to do is clean and idle. 816 */ 817 rounding = max_t(xfs_off_t, xfs_inode_alloc_unitsize(ip), PAGE_SIZE); 818 start = rounddown_64(offset, rounding); 819 end = roundup_64(offset + len, rounding) - 1; 820 821 error = filemap_write_and_wait_range(inode->i_mapping, start, end); 822 if (error) 823 return error; 824 truncate_pagecache_range(inode, start, end); 825 return 0; 826 } 827 828 int 829 xfs_free_file_space( 830 struct xfs_inode *ip, 831 xfs_off_t offset, 832 xfs_off_t len) 833 { 834 struct xfs_mount *mp = ip->i_mount; 835 xfs_fileoff_t startoffset_fsb; 836 xfs_fileoff_t endoffset_fsb; 837 int done = 0, error; 838 839 trace_xfs_free_file_space(ip); 840 841 error = xfs_qm_dqattach(ip); 842 if (error) 843 return error; 844 845 if (len <= 0) /* if nothing being freed */ 846 return 0; 847 848 /* 849 * Now AIO and DIO has drained we flush and (if necessary) invalidate 850 * the cached range over the first operation we are about to run. 851 */ 852 error = xfs_flush_unmap_range(ip, offset, len); 853 if (error) 854 return error; 855 856 startoffset_fsb = XFS_B_TO_FSB(mp, offset); 857 endoffset_fsb = XFS_B_TO_FSBT(mp, offset + len); 858 859 /* We can only free complete realtime extents. */ 860 if (xfs_inode_has_bigrtalloc(ip)) { 861 startoffset_fsb = xfs_rtb_roundup_rtx(mp, startoffset_fsb); 862 endoffset_fsb = xfs_rtb_rounddown_rtx(mp, endoffset_fsb); 863 } 864 865 /* 866 * Need to zero the stuff we're not freeing, on disk. 867 */ 868 if (endoffset_fsb > startoffset_fsb) { 869 while (!done) { 870 error = xfs_unmap_extent(ip, startoffset_fsb, 871 endoffset_fsb - startoffset_fsb, &done); 872 if (error) 873 return error; 874 } 875 } 876 877 /* 878 * Now that we've unmap all full blocks we'll have to zero out any 879 * partial block at the beginning and/or end. xfs_zero_range is smart 880 * enough to skip any holes, including those we just created, but we 881 * must take care not to zero beyond EOF and enlarge i_size. 882 */ 883 if (offset >= XFS_ISIZE(ip)) 884 return 0; 885 if (offset + len > XFS_ISIZE(ip)) 886 len = XFS_ISIZE(ip) - offset; 887 error = xfs_zero_range(ip, offset, len, NULL); 888 if (error) 889 return error; 890 891 /* 892 * If we zeroed right up to EOF and EOF straddles a page boundary we 893 * must make sure that the post-EOF area is also zeroed because the 894 * page could be mmap'd and xfs_zero_range doesn't do that for us. 895 * Writeback of the eof page will do this, albeit clumsily. 896 */ 897 if (offset + len >= XFS_ISIZE(ip) && offset_in_page(offset + len) > 0) { 898 error = filemap_write_and_wait_range(VFS_I(ip)->i_mapping, 899 round_down(offset + len, PAGE_SIZE), LLONG_MAX); 900 } 901 902 return error; 903 } 904 905 static int 906 xfs_prepare_shift( 907 struct xfs_inode *ip, 908 loff_t offset) 909 { 910 unsigned int rounding; 911 int error; 912 913 /* 914 * Trim eofblocks to avoid shifting uninitialized post-eof preallocation 915 * into the accessible region of the file. 916 */ 917 if (xfs_can_free_eofblocks(ip)) { 918 error = xfs_free_eofblocks(ip); 919 if (error) 920 return error; 921 } 922 923 /* 924 * Shift operations must stabilize the start block offset boundary along 925 * with the full range of the operation. If we don't, a COW writeback 926 * completion could race with an insert, front merge with the start 927 * extent (after split) during the shift and corrupt the file. Start 928 * with the allocation unit just prior to the start to stabilize the 929 * boundary. 930 */ 931 rounding = xfs_inode_alloc_unitsize(ip); 932 offset = rounddown_64(offset, rounding); 933 if (offset) 934 offset -= rounding; 935 936 /* 937 * Writeback and invalidate cache for the remainder of the file as we're 938 * about to shift down every extent from offset to EOF. 939 */ 940 error = xfs_flush_unmap_range(ip, offset, XFS_ISIZE(ip)); 941 if (error) 942 return error; 943 944 /* 945 * Clean out anything hanging around in the cow fork now that 946 * we've flushed all the dirty data out to disk to avoid having 947 * CoW extents at the wrong offsets. 948 */ 949 if (xfs_inode_has_cow_data(ip)) { 950 error = xfs_reflink_cancel_cow_range(ip, offset, NULLFILEOFF, 951 true); 952 if (error) 953 return error; 954 } 955 956 return 0; 957 } 958 959 /* 960 * xfs_collapse_file_space() 961 * This routine frees disk space and shift extent for the given file. 962 * The first thing we do is to free data blocks in the specified range 963 * by calling xfs_free_file_space(). It would also sync dirty data 964 * and invalidate page cache over the region on which collapse range 965 * is working. And Shift extent records to the left to cover a hole. 966 * RETURNS: 967 * 0 on success 968 * errno on error 969 * 970 */ 971 int 972 xfs_collapse_file_space( 973 struct xfs_inode *ip, 974 xfs_off_t offset, 975 xfs_off_t len) 976 { 977 struct xfs_mount *mp = ip->i_mount; 978 struct xfs_trans *tp; 979 int error; 980 xfs_fileoff_t next_fsb = XFS_B_TO_FSB(mp, offset + len); 981 xfs_fileoff_t shift_fsb = XFS_B_TO_FSB(mp, len); 982 bool done = false; 983 984 xfs_assert_ilocked(ip, XFS_IOLOCK_EXCL | XFS_MMAPLOCK_EXCL); 985 986 trace_xfs_collapse_file_space(ip); 987 988 error = xfs_free_file_space(ip, offset, len); 989 if (error) 990 return error; 991 992 error = xfs_prepare_shift(ip, offset); 993 if (error) 994 return error; 995 996 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, 0, 0, 0, &tp); 997 if (error) 998 return error; 999 1000 xfs_ilock(ip, XFS_ILOCK_EXCL); 1001 xfs_trans_ijoin(tp, ip, 0); 1002 1003 while (!done) { 1004 error = xfs_bmap_collapse_extents(tp, ip, &next_fsb, shift_fsb, 1005 &done); 1006 if (error) 1007 goto out_trans_cancel; 1008 if (done) 1009 break; 1010 1011 /* finish any deferred frees and roll the transaction */ 1012 error = xfs_defer_finish(&tp); 1013 if (error) 1014 goto out_trans_cancel; 1015 } 1016 1017 error = xfs_trans_commit(tp); 1018 xfs_iunlock(ip, XFS_ILOCK_EXCL); 1019 return error; 1020 1021 out_trans_cancel: 1022 xfs_trans_cancel(tp); 1023 xfs_iunlock(ip, XFS_ILOCK_EXCL); 1024 return error; 1025 } 1026 1027 /* 1028 * xfs_insert_file_space() 1029 * This routine create hole space by shifting extents for the given file. 1030 * The first thing we do is to sync dirty data and invalidate page cache 1031 * over the region on which insert range is working. And split an extent 1032 * to two extents at given offset by calling xfs_bmap_split_extent. 1033 * And shift all extent records which are laying between [offset, 1034 * last allocated extent] to the right to reserve hole range. 1035 * RETURNS: 1036 * 0 on success 1037 * errno on error 1038 */ 1039 int 1040 xfs_insert_file_space( 1041 struct xfs_inode *ip, 1042 loff_t offset, 1043 loff_t len) 1044 { 1045 struct xfs_mount *mp = ip->i_mount; 1046 struct xfs_trans *tp; 1047 int error; 1048 xfs_fileoff_t stop_fsb = XFS_B_TO_FSB(mp, offset); 1049 xfs_fileoff_t next_fsb = NULLFSBLOCK; 1050 xfs_fileoff_t shift_fsb = XFS_B_TO_FSB(mp, len); 1051 bool done = false; 1052 1053 xfs_assert_ilocked(ip, XFS_IOLOCK_EXCL | XFS_MMAPLOCK_EXCL); 1054 1055 trace_xfs_insert_file_space(ip); 1056 1057 error = xfs_bmap_can_insert_extents(ip, stop_fsb, shift_fsb); 1058 if (error) 1059 return error; 1060 1061 error = xfs_prepare_shift(ip, offset); 1062 if (error) 1063 return error; 1064 1065 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, 1066 XFS_DIOSTRAT_SPACE_RES(mp, 0), 0, 0, &tp); 1067 if (error) 1068 return error; 1069 1070 xfs_ilock(ip, XFS_ILOCK_EXCL); 1071 xfs_trans_ijoin(tp, ip, 0); 1072 1073 error = xfs_iext_count_extend(tp, ip, XFS_DATA_FORK, 1074 XFS_IEXT_PUNCH_HOLE_CNT); 1075 if (error) 1076 goto out_trans_cancel; 1077 1078 /* 1079 * The extent shifting code works on extent granularity. So, if stop_fsb 1080 * is not the starting block of extent, we need to split the extent at 1081 * stop_fsb. 1082 */ 1083 error = xfs_bmap_split_extent(tp, ip, stop_fsb); 1084 if (error) 1085 goto out_trans_cancel; 1086 1087 do { 1088 error = xfs_defer_finish(&tp); 1089 if (error) 1090 goto out_trans_cancel; 1091 1092 error = xfs_bmap_insert_extents(tp, ip, &next_fsb, shift_fsb, 1093 &done, stop_fsb); 1094 if (error) 1095 goto out_trans_cancel; 1096 } while (!done); 1097 1098 error = xfs_trans_commit(tp); 1099 xfs_iunlock(ip, XFS_ILOCK_EXCL); 1100 return error; 1101 1102 out_trans_cancel: 1103 xfs_trans_cancel(tp); 1104 xfs_iunlock(ip, XFS_ILOCK_EXCL); 1105 return error; 1106 } 1107 1108 /* 1109 * We need to check that the format of the data fork in the temporary inode is 1110 * valid for the target inode before doing the swap. This is not a problem with 1111 * attr1 because of the fixed fork offset, but attr2 has a dynamically sized 1112 * data fork depending on the space the attribute fork is taking so we can get 1113 * invalid formats on the target inode. 1114 * 1115 * E.g. target has space for 7 extents in extent format, temp inode only has 1116 * space for 6. If we defragment down to 7 extents, then the tmp format is a 1117 * btree, but when swapped it needs to be in extent format. Hence we can't just 1118 * blindly swap data forks on attr2 filesystems. 1119 * 1120 * Note that we check the swap in both directions so that we don't end up with 1121 * a corrupt temporary inode, either. 1122 * 1123 * Note that fixing the way xfs_fsr sets up the attribute fork in the source 1124 * inode will prevent this situation from occurring, so all we do here is 1125 * reject and log the attempt. basically we are putting the responsibility on 1126 * userspace to get this right. 1127 */ 1128 static int 1129 xfs_swap_extents_check_format( 1130 struct xfs_inode *ip, /* target inode */ 1131 struct xfs_inode *tip) /* tmp inode */ 1132 { 1133 struct xfs_ifork *ifp = &ip->i_df; 1134 struct xfs_ifork *tifp = &tip->i_df; 1135 1136 /* User/group/project quota ids must match if quotas are enforced. */ 1137 if (XFS_IS_QUOTA_ON(ip->i_mount) && 1138 (!uid_eq(VFS_I(ip)->i_uid, VFS_I(tip)->i_uid) || 1139 !gid_eq(VFS_I(ip)->i_gid, VFS_I(tip)->i_gid) || 1140 ip->i_projid != tip->i_projid)) 1141 return -EINVAL; 1142 1143 /* Should never get a local format */ 1144 if (ifp->if_format == XFS_DINODE_FMT_LOCAL || 1145 tifp->if_format == XFS_DINODE_FMT_LOCAL) 1146 return -EINVAL; 1147 1148 /* 1149 * if the target inode has less extents that then temporary inode then 1150 * why did userspace call us? 1151 */ 1152 if (ifp->if_nextents < tifp->if_nextents) 1153 return -EINVAL; 1154 1155 /* 1156 * If we have to use the (expensive) rmap swap method, we can 1157 * handle any number of extents and any format. 1158 */ 1159 if (xfs_has_rmapbt(ip->i_mount)) 1160 return 0; 1161 1162 /* 1163 * if the target inode is in extent form and the temp inode is in btree 1164 * form then we will end up with the target inode in the wrong format 1165 * as we already know there are less extents in the temp inode. 1166 */ 1167 if (ifp->if_format == XFS_DINODE_FMT_EXTENTS && 1168 tifp->if_format == XFS_DINODE_FMT_BTREE) 1169 return -EINVAL; 1170 1171 /* Check temp in extent form to max in target */ 1172 if (tifp->if_format == XFS_DINODE_FMT_EXTENTS && 1173 tifp->if_nextents > XFS_IFORK_MAXEXT(ip, XFS_DATA_FORK)) 1174 return -EINVAL; 1175 1176 /* Check target in extent form to max in temp */ 1177 if (ifp->if_format == XFS_DINODE_FMT_EXTENTS && 1178 ifp->if_nextents > XFS_IFORK_MAXEXT(tip, XFS_DATA_FORK)) 1179 return -EINVAL; 1180 1181 /* 1182 * If we are in a btree format, check that the temp root block will fit 1183 * in the target and that it has enough extents to be in btree format 1184 * in the target. 1185 * 1186 * Note that we have to be careful to allow btree->extent conversions 1187 * (a common defrag case) which will occur when the temp inode is in 1188 * extent format... 1189 */ 1190 if (tifp->if_format == XFS_DINODE_FMT_BTREE) { 1191 if (xfs_inode_has_attr_fork(ip) && 1192 xfs_bmap_bmdr_space(tifp->if_broot) > xfs_inode_fork_boff(ip)) 1193 return -EINVAL; 1194 if (tifp->if_nextents <= XFS_IFORK_MAXEXT(ip, XFS_DATA_FORK)) 1195 return -EINVAL; 1196 } 1197 1198 /* Reciprocal target->temp btree format checks */ 1199 if (ifp->if_format == XFS_DINODE_FMT_BTREE) { 1200 if (xfs_inode_has_attr_fork(tip) && 1201 xfs_bmap_bmdr_space(ip->i_df.if_broot) > xfs_inode_fork_boff(tip)) 1202 return -EINVAL; 1203 if (ifp->if_nextents <= XFS_IFORK_MAXEXT(tip, XFS_DATA_FORK)) 1204 return -EINVAL; 1205 } 1206 1207 return 0; 1208 } 1209 1210 static int 1211 xfs_swap_extent_flush( 1212 struct xfs_inode *ip) 1213 { 1214 int error; 1215 1216 error = filemap_write_and_wait(VFS_I(ip)->i_mapping); 1217 if (error) 1218 return error; 1219 truncate_pagecache_range(VFS_I(ip), 0, -1); 1220 1221 /* Verify O_DIRECT for ftmp */ 1222 if (VFS_I(ip)->i_mapping->nrpages) 1223 return -EINVAL; 1224 return 0; 1225 } 1226 1227 /* 1228 * Move extents from one file to another, when rmap is enabled. 1229 */ 1230 STATIC int 1231 xfs_swap_extent_rmap( 1232 struct xfs_trans **tpp, 1233 struct xfs_inode *ip, 1234 struct xfs_inode *tip) 1235 { 1236 struct xfs_trans *tp = *tpp; 1237 struct xfs_bmbt_irec irec; 1238 struct xfs_bmbt_irec uirec; 1239 struct xfs_bmbt_irec tirec; 1240 xfs_fileoff_t offset_fsb; 1241 xfs_fileoff_t end_fsb; 1242 xfs_filblks_t count_fsb; 1243 int error; 1244 xfs_filblks_t ilen; 1245 xfs_filblks_t rlen; 1246 int nimaps; 1247 uint64_t tip_flags2; 1248 1249 /* 1250 * If the source file has shared blocks, we must flag the donor 1251 * file as having shared blocks so that we get the shared-block 1252 * rmap functions when we go to fix up the rmaps. The flags 1253 * will be switch for reals later. 1254 */ 1255 tip_flags2 = tip->i_diflags2; 1256 if (ip->i_diflags2 & XFS_DIFLAG2_REFLINK) 1257 tip->i_diflags2 |= XFS_DIFLAG2_REFLINK; 1258 1259 offset_fsb = 0; 1260 end_fsb = XFS_B_TO_FSB(ip->i_mount, i_size_read(VFS_I(ip))); 1261 count_fsb = (xfs_filblks_t)(end_fsb - offset_fsb); 1262 1263 while (count_fsb) { 1264 /* Read extent from the donor file */ 1265 nimaps = 1; 1266 error = xfs_bmapi_read(tip, offset_fsb, count_fsb, &tirec, 1267 &nimaps, 0); 1268 if (error) 1269 goto out; 1270 ASSERT(nimaps == 1); 1271 ASSERT(tirec.br_startblock != DELAYSTARTBLOCK); 1272 1273 trace_xfs_swap_extent_rmap_remap(tip, &tirec); 1274 ilen = tirec.br_blockcount; 1275 1276 /* Unmap the old blocks in the source file. */ 1277 while (tirec.br_blockcount) { 1278 ASSERT(tp->t_highest_agno == NULLAGNUMBER); 1279 trace_xfs_swap_extent_rmap_remap_piece(tip, &tirec); 1280 1281 /* Read extent from the source file */ 1282 nimaps = 1; 1283 error = xfs_bmapi_read(ip, tirec.br_startoff, 1284 tirec.br_blockcount, &irec, 1285 &nimaps, 0); 1286 if (error) 1287 goto out; 1288 ASSERT(nimaps == 1); 1289 ASSERT(tirec.br_startoff == irec.br_startoff); 1290 trace_xfs_swap_extent_rmap_remap_piece(ip, &irec); 1291 1292 /* Trim the extent. */ 1293 uirec = tirec; 1294 uirec.br_blockcount = rlen = min_t(xfs_filblks_t, 1295 tirec.br_blockcount, 1296 irec.br_blockcount); 1297 trace_xfs_swap_extent_rmap_remap_piece(tip, &uirec); 1298 1299 if (xfs_bmap_is_real_extent(&uirec)) { 1300 error = xfs_iext_count_extend(tp, ip, 1301 XFS_DATA_FORK, 1302 XFS_IEXT_SWAP_RMAP_CNT); 1303 if (error) 1304 goto out; 1305 } 1306 1307 if (xfs_bmap_is_real_extent(&irec)) { 1308 error = xfs_iext_count_extend(tp, tip, 1309 XFS_DATA_FORK, 1310 XFS_IEXT_SWAP_RMAP_CNT); 1311 if (error) 1312 goto out; 1313 } 1314 1315 /* Remove the mapping from the donor file. */ 1316 xfs_bmap_unmap_extent(tp, tip, XFS_DATA_FORK, &uirec); 1317 1318 /* Remove the mapping from the source file. */ 1319 xfs_bmap_unmap_extent(tp, ip, XFS_DATA_FORK, &irec); 1320 1321 /* Map the donor file's blocks into the source file. */ 1322 xfs_bmap_map_extent(tp, ip, XFS_DATA_FORK, &uirec); 1323 1324 /* Map the source file's blocks into the donor file. */ 1325 xfs_bmap_map_extent(tp, tip, XFS_DATA_FORK, &irec); 1326 1327 error = xfs_defer_finish(tpp); 1328 tp = *tpp; 1329 if (error) 1330 goto out; 1331 1332 tirec.br_startoff += rlen; 1333 if (tirec.br_startblock != HOLESTARTBLOCK && 1334 tirec.br_startblock != DELAYSTARTBLOCK) 1335 tirec.br_startblock += rlen; 1336 tirec.br_blockcount -= rlen; 1337 } 1338 1339 /* Roll on... */ 1340 count_fsb -= ilen; 1341 offset_fsb += ilen; 1342 } 1343 1344 tip->i_diflags2 = tip_flags2; 1345 return 0; 1346 1347 out: 1348 trace_xfs_swap_extent_rmap_error(ip, error, _RET_IP_); 1349 tip->i_diflags2 = tip_flags2; 1350 return error; 1351 } 1352 1353 /* Swap the extents of two files by swapping data forks. */ 1354 STATIC int 1355 xfs_swap_extent_forks( 1356 struct xfs_trans *tp, 1357 struct xfs_inode *ip, 1358 struct xfs_inode *tip, 1359 int *src_log_flags, 1360 int *target_log_flags) 1361 { 1362 xfs_filblks_t aforkblks = 0; 1363 xfs_filblks_t taforkblks = 0; 1364 xfs_extnum_t junk; 1365 uint64_t tmp; 1366 int error; 1367 1368 /* 1369 * Count the number of extended attribute blocks 1370 */ 1371 if (xfs_inode_has_attr_fork(ip) && ip->i_af.if_nextents > 0 && 1372 ip->i_af.if_format != XFS_DINODE_FMT_LOCAL) { 1373 error = xfs_bmap_count_blocks(tp, ip, XFS_ATTR_FORK, &junk, 1374 &aforkblks); 1375 if (error) 1376 return error; 1377 } 1378 if (xfs_inode_has_attr_fork(tip) && tip->i_af.if_nextents > 0 && 1379 tip->i_af.if_format != XFS_DINODE_FMT_LOCAL) { 1380 error = xfs_bmap_count_blocks(tp, tip, XFS_ATTR_FORK, &junk, 1381 &taforkblks); 1382 if (error) 1383 return error; 1384 } 1385 1386 /* 1387 * Btree format (v3) inodes have the inode number stamped in the bmbt 1388 * block headers. We can't start changing the bmbt blocks until the 1389 * inode owner change is logged so recovery does the right thing in the 1390 * event of a crash. Set the owner change log flags now and leave the 1391 * bmbt scan as the last step. 1392 */ 1393 if (xfs_has_v3inodes(ip->i_mount)) { 1394 if (ip->i_df.if_format == XFS_DINODE_FMT_BTREE) 1395 (*target_log_flags) |= XFS_ILOG_DOWNER; 1396 if (tip->i_df.if_format == XFS_DINODE_FMT_BTREE) 1397 (*src_log_flags) |= XFS_ILOG_DOWNER; 1398 } 1399 1400 /* 1401 * Swap the data forks of the inodes 1402 */ 1403 swap(ip->i_df, tip->i_df); 1404 1405 /* 1406 * Fix the on-disk inode values 1407 */ 1408 tmp = (uint64_t)ip->i_nblocks; 1409 ip->i_nblocks = tip->i_nblocks - taforkblks + aforkblks; 1410 tip->i_nblocks = tmp + taforkblks - aforkblks; 1411 1412 /* 1413 * The extents in the source inode could still contain speculative 1414 * preallocation beyond EOF (e.g. the file is open but not modified 1415 * while defrag is in progress). In that case, we need to copy over the 1416 * number of delalloc blocks the data fork in the source inode is 1417 * tracking beyond EOF so that when the fork is truncated away when the 1418 * temporary inode is unlinked we don't underrun the i_delayed_blks 1419 * counter on that inode. 1420 */ 1421 ASSERT(tip->i_delayed_blks == 0); 1422 tip->i_delayed_blks = ip->i_delayed_blks; 1423 ip->i_delayed_blks = 0; 1424 1425 switch (ip->i_df.if_format) { 1426 case XFS_DINODE_FMT_EXTENTS: 1427 (*src_log_flags) |= XFS_ILOG_DEXT; 1428 break; 1429 case XFS_DINODE_FMT_BTREE: 1430 ASSERT(!xfs_has_v3inodes(ip->i_mount) || 1431 (*src_log_flags & XFS_ILOG_DOWNER)); 1432 (*src_log_flags) |= XFS_ILOG_DBROOT; 1433 break; 1434 } 1435 1436 switch (tip->i_df.if_format) { 1437 case XFS_DINODE_FMT_EXTENTS: 1438 (*target_log_flags) |= XFS_ILOG_DEXT; 1439 break; 1440 case XFS_DINODE_FMT_BTREE: 1441 (*target_log_flags) |= XFS_ILOG_DBROOT; 1442 ASSERT(!xfs_has_v3inodes(ip->i_mount) || 1443 (*target_log_flags & XFS_ILOG_DOWNER)); 1444 break; 1445 } 1446 1447 return 0; 1448 } 1449 1450 /* 1451 * Fix up the owners of the bmbt blocks to refer to the current inode. The 1452 * change owner scan attempts to order all modified buffers in the current 1453 * transaction. In the event of ordered buffer failure, the offending buffer is 1454 * physically logged as a fallback and the scan returns -EAGAIN. We must roll 1455 * the transaction in this case to replenish the fallback log reservation and 1456 * restart the scan. This process repeats until the scan completes. 1457 */ 1458 static int 1459 xfs_swap_change_owner( 1460 struct xfs_trans **tpp, 1461 struct xfs_inode *ip, 1462 struct xfs_inode *tmpip) 1463 { 1464 int error; 1465 struct xfs_trans *tp = *tpp; 1466 1467 do { 1468 error = xfs_bmbt_change_owner(tp, ip, XFS_DATA_FORK, ip->i_ino, 1469 NULL); 1470 /* success or fatal error */ 1471 if (error != -EAGAIN) 1472 break; 1473 1474 error = xfs_trans_roll(tpp); 1475 if (error) 1476 break; 1477 tp = *tpp; 1478 1479 /* 1480 * Redirty both inodes so they can relog and keep the log tail 1481 * moving forward. 1482 */ 1483 xfs_trans_ijoin(tp, ip, 0); 1484 xfs_trans_ijoin(tp, tmpip, 0); 1485 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE); 1486 xfs_trans_log_inode(tp, tmpip, XFS_ILOG_CORE); 1487 } while (true); 1488 1489 return error; 1490 } 1491 1492 int 1493 xfs_swap_extents( 1494 struct xfs_inode *ip, /* target inode */ 1495 struct xfs_inode *tip, /* tmp inode */ 1496 struct xfs_swapext *sxp) 1497 { 1498 struct xfs_mount *mp = ip->i_mount; 1499 struct xfs_trans *tp; 1500 struct xfs_bstat *sbp = &sxp->sx_stat; 1501 int src_log_flags, target_log_flags; 1502 int error = 0; 1503 uint64_t f; 1504 int resblks = 0; 1505 unsigned int flags = 0; 1506 struct timespec64 ctime, mtime; 1507 1508 /* 1509 * Lock the inodes against other IO, page faults and truncate to 1510 * begin with. Then we can ensure the inodes are flushed and have no 1511 * page cache safely. Once we have done this we can take the ilocks and 1512 * do the rest of the checks. 1513 */ 1514 lock_two_nondirectories(VFS_I(ip), VFS_I(tip)); 1515 filemap_invalidate_lock_two(VFS_I(ip)->i_mapping, 1516 VFS_I(tip)->i_mapping); 1517 1518 /* Verify that both files have the same format */ 1519 if ((VFS_I(ip)->i_mode & S_IFMT) != (VFS_I(tip)->i_mode & S_IFMT)) { 1520 error = -EINVAL; 1521 goto out_unlock; 1522 } 1523 1524 /* Verify both files are either real-time or non-realtime */ 1525 if (XFS_IS_REALTIME_INODE(ip) != XFS_IS_REALTIME_INODE(tip)) { 1526 error = -EINVAL; 1527 goto out_unlock; 1528 } 1529 1530 error = xfs_qm_dqattach(ip); 1531 if (error) 1532 goto out_unlock; 1533 1534 error = xfs_qm_dqattach(tip); 1535 if (error) 1536 goto out_unlock; 1537 1538 error = xfs_swap_extent_flush(ip); 1539 if (error) 1540 goto out_unlock; 1541 error = xfs_swap_extent_flush(tip); 1542 if (error) 1543 goto out_unlock; 1544 1545 if (xfs_inode_has_cow_data(tip)) { 1546 error = xfs_reflink_cancel_cow_range(tip, 0, NULLFILEOFF, true); 1547 if (error) 1548 goto out_unlock; 1549 } 1550 1551 /* 1552 * Extent "swapping" with rmap requires a permanent reservation and 1553 * a block reservation because it's really just a remap operation 1554 * performed with log redo items! 1555 */ 1556 if (xfs_has_rmapbt(mp)) { 1557 int w = XFS_DATA_FORK; 1558 uint32_t ipnext = ip->i_df.if_nextents; 1559 uint32_t tipnext = tip->i_df.if_nextents; 1560 1561 /* 1562 * Conceptually this shouldn't affect the shape of either bmbt, 1563 * but since we atomically move extents one by one, we reserve 1564 * enough space to rebuild both trees. 1565 */ 1566 resblks = XFS_SWAP_RMAP_SPACE_RES(mp, ipnext, w); 1567 resblks += XFS_SWAP_RMAP_SPACE_RES(mp, tipnext, w); 1568 1569 /* 1570 * If either inode straddles a bmapbt block allocation boundary, 1571 * the rmapbt algorithm triggers repeated allocs and frees as 1572 * extents are remapped. This can exhaust the block reservation 1573 * prematurely and cause shutdown. Return freed blocks to the 1574 * transaction reservation to counter this behavior. 1575 */ 1576 flags |= XFS_TRANS_RES_FDBLKS; 1577 } 1578 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, resblks, 0, flags, 1579 &tp); 1580 if (error) 1581 goto out_unlock; 1582 1583 /* 1584 * Lock and join the inodes to the tansaction so that transaction commit 1585 * or cancel will unlock the inodes from this point onwards. 1586 */ 1587 xfs_lock_two_inodes(ip, XFS_ILOCK_EXCL, tip, XFS_ILOCK_EXCL); 1588 xfs_trans_ijoin(tp, ip, 0); 1589 xfs_trans_ijoin(tp, tip, 0); 1590 1591 1592 /* Verify all data are being swapped */ 1593 if (sxp->sx_offset != 0 || 1594 sxp->sx_length != ip->i_disk_size || 1595 sxp->sx_length != tip->i_disk_size) { 1596 error = -EFAULT; 1597 goto out_trans_cancel; 1598 } 1599 1600 trace_xfs_swap_extent_before(ip, 0); 1601 trace_xfs_swap_extent_before(tip, 1); 1602 1603 /* check inode formats now that data is flushed */ 1604 error = xfs_swap_extents_check_format(ip, tip); 1605 if (error) { 1606 xfs_notice(mp, 1607 "%s: inode 0x%llx format is incompatible for exchanging.", 1608 __func__, ip->i_ino); 1609 goto out_trans_cancel; 1610 } 1611 1612 /* 1613 * Compare the current change & modify times with that 1614 * passed in. If they differ, we abort this swap. 1615 * This is the mechanism used to ensure the calling 1616 * process that the file was not changed out from 1617 * under it. 1618 */ 1619 ctime = inode_get_ctime(VFS_I(ip)); 1620 mtime = inode_get_mtime(VFS_I(ip)); 1621 if ((sbp->bs_ctime.tv_sec != ctime.tv_sec) || 1622 (sbp->bs_ctime.tv_nsec != ctime.tv_nsec) || 1623 (sbp->bs_mtime.tv_sec != mtime.tv_sec) || 1624 (sbp->bs_mtime.tv_nsec != mtime.tv_nsec)) { 1625 error = -EBUSY; 1626 goto out_trans_cancel; 1627 } 1628 1629 /* 1630 * Note the trickiness in setting the log flags - we set the owner log 1631 * flag on the opposite inode (i.e. the inode we are setting the new 1632 * owner to be) because once we swap the forks and log that, log 1633 * recovery is going to see the fork as owned by the swapped inode, 1634 * not the pre-swapped inodes. 1635 */ 1636 src_log_flags = XFS_ILOG_CORE; 1637 target_log_flags = XFS_ILOG_CORE; 1638 1639 if (xfs_has_rmapbt(mp)) 1640 error = xfs_swap_extent_rmap(&tp, ip, tip); 1641 else 1642 error = xfs_swap_extent_forks(tp, ip, tip, &src_log_flags, 1643 &target_log_flags); 1644 if (error) 1645 goto out_trans_cancel; 1646 1647 /* Do we have to swap reflink flags? */ 1648 if ((ip->i_diflags2 & XFS_DIFLAG2_REFLINK) ^ 1649 (tip->i_diflags2 & XFS_DIFLAG2_REFLINK)) { 1650 f = ip->i_diflags2 & XFS_DIFLAG2_REFLINK; 1651 ip->i_diflags2 &= ~XFS_DIFLAG2_REFLINK; 1652 ip->i_diflags2 |= tip->i_diflags2 & XFS_DIFLAG2_REFLINK; 1653 tip->i_diflags2 &= ~XFS_DIFLAG2_REFLINK; 1654 tip->i_diflags2 |= f & XFS_DIFLAG2_REFLINK; 1655 } 1656 1657 /* Swap the cow forks. */ 1658 if (xfs_has_reflink(mp)) { 1659 ASSERT(!ip->i_cowfp || 1660 ip->i_cowfp->if_format == XFS_DINODE_FMT_EXTENTS); 1661 ASSERT(!tip->i_cowfp || 1662 tip->i_cowfp->if_format == XFS_DINODE_FMT_EXTENTS); 1663 1664 swap(ip->i_cowfp, tip->i_cowfp); 1665 1666 if (ip->i_cowfp && ip->i_cowfp->if_bytes) 1667 xfs_inode_set_cowblocks_tag(ip); 1668 else 1669 xfs_inode_clear_cowblocks_tag(ip); 1670 if (tip->i_cowfp && tip->i_cowfp->if_bytes) 1671 xfs_inode_set_cowblocks_tag(tip); 1672 else 1673 xfs_inode_clear_cowblocks_tag(tip); 1674 } 1675 1676 xfs_trans_log_inode(tp, ip, src_log_flags); 1677 xfs_trans_log_inode(tp, tip, target_log_flags); 1678 1679 /* 1680 * The extent forks have been swapped, but crc=1,rmapbt=0 filesystems 1681 * have inode number owner values in the bmbt blocks that still refer to 1682 * the old inode. Scan each bmbt to fix up the owner values with the 1683 * inode number of the current inode. 1684 */ 1685 if (src_log_flags & XFS_ILOG_DOWNER) { 1686 error = xfs_swap_change_owner(&tp, ip, tip); 1687 if (error) 1688 goto out_trans_cancel; 1689 } 1690 if (target_log_flags & XFS_ILOG_DOWNER) { 1691 error = xfs_swap_change_owner(&tp, tip, ip); 1692 if (error) 1693 goto out_trans_cancel; 1694 } 1695 1696 /* 1697 * If this is a synchronous mount, make sure that the 1698 * transaction goes to disk before returning to the user. 1699 */ 1700 if (xfs_has_wsync(mp)) 1701 xfs_trans_set_sync(tp); 1702 1703 error = xfs_trans_commit(tp); 1704 1705 trace_xfs_swap_extent_after(ip, 0); 1706 trace_xfs_swap_extent_after(tip, 1); 1707 1708 out_unlock_ilock: 1709 xfs_iunlock(ip, XFS_ILOCK_EXCL); 1710 xfs_iunlock(tip, XFS_ILOCK_EXCL); 1711 out_unlock: 1712 filemap_invalidate_unlock_two(VFS_I(ip)->i_mapping, 1713 VFS_I(tip)->i_mapping); 1714 unlock_two_nondirectories(VFS_I(ip), VFS_I(tip)); 1715 return error; 1716 1717 out_trans_cancel: 1718 xfs_trans_cancel(tp); 1719 goto out_unlock_ilock; 1720 } 1721