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 32 /* Kernel only BMAP related definitions and functions */ 33 34 /* 35 * Convert the given file system block to a disk block. We have to treat it 36 * differently based on whether the file is a real time file or not, because the 37 * bmap code does. 38 */ 39 xfs_daddr_t 40 xfs_fsb_to_db(struct xfs_inode *ip, xfs_fsblock_t fsb) 41 { 42 if (XFS_IS_REALTIME_INODE(ip)) 43 return XFS_FSB_TO_BB(ip->i_mount, fsb); 44 return XFS_FSB_TO_DADDR(ip->i_mount, fsb); 45 } 46 47 /* 48 * Routine to zero an extent on disk allocated to the specific inode. 49 * 50 * The VFS functions take a linearised filesystem block offset, so we have to 51 * convert the sparse xfs fsb to the right format first. 52 * VFS types are real funky, too. 53 */ 54 int 55 xfs_zero_extent( 56 struct xfs_inode *ip, 57 xfs_fsblock_t start_fsb, 58 xfs_off_t count_fsb) 59 { 60 struct xfs_mount *mp = ip->i_mount; 61 struct xfs_buftarg *target = xfs_inode_buftarg(ip); 62 xfs_daddr_t sector = xfs_fsb_to_db(ip, start_fsb); 63 sector_t block = XFS_BB_TO_FSBT(mp, sector); 64 65 return blkdev_issue_zeroout(target->bt_bdev, 66 block << (mp->m_super->s_blocksize_bits - 9), 67 count_fsb << (mp->m_super->s_blocksize_bits - 9), 68 GFP_NOFS, 0); 69 } 70 71 #ifdef CONFIG_XFS_RT 72 int 73 xfs_bmap_rtalloc( 74 struct xfs_bmalloca *ap) 75 { 76 struct xfs_mount *mp = ap->ip->i_mount; 77 xfs_fileoff_t orig_offset = ap->offset; 78 xfs_rtblock_t rtb; 79 xfs_extlen_t prod = 0; /* product factor for allocators */ 80 xfs_extlen_t mod = 0; /* product factor for allocators */ 81 xfs_extlen_t ralen = 0; /* realtime allocation length */ 82 xfs_extlen_t align; /* minimum allocation alignment */ 83 xfs_extlen_t orig_length = ap->length; 84 xfs_extlen_t minlen = mp->m_sb.sb_rextsize; 85 xfs_extlen_t raminlen; 86 bool rtlocked = false; 87 bool ignore_locality = false; 88 int error; 89 90 align = xfs_get_extsz_hint(ap->ip); 91 retry: 92 prod = align / mp->m_sb.sb_rextsize; 93 error = xfs_bmap_extsize_align(mp, &ap->got, &ap->prev, 94 align, 1, ap->eof, 0, 95 ap->conv, &ap->offset, &ap->length); 96 if (error) 97 return error; 98 ASSERT(ap->length); 99 ASSERT(ap->length % mp->m_sb.sb_rextsize == 0); 100 101 /* 102 * If we shifted the file offset downward to satisfy an extent size 103 * hint, increase minlen by that amount so that the allocator won't 104 * give us an allocation that's too short to cover at least one of the 105 * blocks that the caller asked for. 106 */ 107 if (ap->offset != orig_offset) 108 minlen += orig_offset - ap->offset; 109 110 /* 111 * If the offset & length are not perfectly aligned 112 * then kill prod, it will just get us in trouble. 113 */ 114 div_u64_rem(ap->offset, align, &mod); 115 if (mod || ap->length % align) 116 prod = 1; 117 /* 118 * Set ralen to be the actual requested length in rtextents. 119 */ 120 ralen = ap->length / mp->m_sb.sb_rextsize; 121 /* 122 * If the old value was close enough to XFS_BMBT_MAX_EXTLEN that 123 * we rounded up to it, cut it back so it's valid again. 124 * Note that if it's a really large request (bigger than 125 * XFS_BMBT_MAX_EXTLEN), we don't hear about that number, and can't 126 * adjust the starting point to match it. 127 */ 128 if (ralen * mp->m_sb.sb_rextsize >= XFS_MAX_BMBT_EXTLEN) 129 ralen = XFS_MAX_BMBT_EXTLEN / mp->m_sb.sb_rextsize; 130 131 /* 132 * Lock out modifications to both the RT bitmap and summary inodes 133 */ 134 if (!rtlocked) { 135 xfs_ilock(mp->m_rbmip, XFS_ILOCK_EXCL|XFS_ILOCK_RTBITMAP); 136 xfs_trans_ijoin(ap->tp, mp->m_rbmip, XFS_ILOCK_EXCL); 137 xfs_ilock(mp->m_rsumip, XFS_ILOCK_EXCL|XFS_ILOCK_RTSUM); 138 xfs_trans_ijoin(ap->tp, mp->m_rsumip, XFS_ILOCK_EXCL); 139 rtlocked = true; 140 } 141 142 /* 143 * If it's an allocation to an empty file at offset 0, 144 * pick an extent that will space things out in the rt area. 145 */ 146 if (ap->eof && ap->offset == 0) { 147 xfs_rtblock_t rtx; /* realtime extent no */ 148 149 error = xfs_rtpick_extent(mp, ap->tp, ralen, &rtx); 150 if (error) 151 return error; 152 ap->blkno = rtx * mp->m_sb.sb_rextsize; 153 } else { 154 ap->blkno = 0; 155 } 156 157 xfs_bmap_adjacent(ap); 158 159 /* 160 * Realtime allocation, done through xfs_rtallocate_extent. 161 */ 162 if (ignore_locality) 163 ap->blkno = 0; 164 else 165 do_div(ap->blkno, mp->m_sb.sb_rextsize); 166 rtb = ap->blkno; 167 ap->length = ralen; 168 raminlen = max_t(xfs_extlen_t, 1, minlen / mp->m_sb.sb_rextsize); 169 error = xfs_rtallocate_extent(ap->tp, ap->blkno, raminlen, ap->length, 170 &ralen, ap->wasdel, prod, &rtb); 171 if (error) 172 return error; 173 174 if (rtb != NULLRTBLOCK) { 175 ap->blkno = rtb * mp->m_sb.sb_rextsize; 176 ap->length = ralen * mp->m_sb.sb_rextsize; 177 ap->ip->i_nblocks += ap->length; 178 xfs_trans_log_inode(ap->tp, ap->ip, XFS_ILOG_CORE); 179 if (ap->wasdel) 180 ap->ip->i_delayed_blks -= ap->length; 181 /* 182 * Adjust the disk quota also. This was reserved 183 * earlier. 184 */ 185 xfs_trans_mod_dquot_byino(ap->tp, ap->ip, 186 ap->wasdel ? XFS_TRANS_DQ_DELRTBCOUNT : 187 XFS_TRANS_DQ_RTBCOUNT, ap->length); 188 return 0; 189 } 190 191 if (align > mp->m_sb.sb_rextsize) { 192 /* 193 * We previously enlarged the request length to try to satisfy 194 * an extent size hint. The allocator didn't return anything, 195 * so reset the parameters to the original values and try again 196 * without alignment criteria. 197 */ 198 ap->offset = orig_offset; 199 ap->length = orig_length; 200 minlen = align = mp->m_sb.sb_rextsize; 201 goto retry; 202 } 203 204 if (!ignore_locality && ap->blkno != 0) { 205 /* 206 * If we can't allocate near a specific rt extent, try again 207 * without locality criteria. 208 */ 209 ignore_locality = true; 210 goto retry; 211 } 212 213 ap->blkno = NULLFSBLOCK; 214 ap->length = 0; 215 return 0; 216 } 217 #endif /* CONFIG_XFS_RT */ 218 219 /* 220 * Extent tree block counting routines. 221 */ 222 223 /* 224 * Count leaf blocks given a range of extent records. Delayed allocation 225 * extents are not counted towards the totals. 226 */ 227 xfs_extnum_t 228 xfs_bmap_count_leaves( 229 struct xfs_ifork *ifp, 230 xfs_filblks_t *count) 231 { 232 struct xfs_iext_cursor icur; 233 struct xfs_bmbt_irec got; 234 xfs_extnum_t numrecs = 0; 235 236 for_each_xfs_iext(ifp, &icur, &got) { 237 if (!isnullstartblock(got.br_startblock)) { 238 *count += got.br_blockcount; 239 numrecs++; 240 } 241 } 242 243 return numrecs; 244 } 245 246 /* 247 * Count fsblocks of the given fork. Delayed allocation extents are 248 * not counted towards the totals. 249 */ 250 int 251 xfs_bmap_count_blocks( 252 struct xfs_trans *tp, 253 struct xfs_inode *ip, 254 int whichfork, 255 xfs_extnum_t *nextents, 256 xfs_filblks_t *count) 257 { 258 struct xfs_mount *mp = ip->i_mount; 259 struct xfs_ifork *ifp = xfs_ifork_ptr(ip, whichfork); 260 struct xfs_btree_cur *cur; 261 xfs_extlen_t btblocks = 0; 262 int error; 263 264 *nextents = 0; 265 *count = 0; 266 267 if (!ifp) 268 return 0; 269 270 switch (ifp->if_format) { 271 case XFS_DINODE_FMT_BTREE: 272 error = xfs_iread_extents(tp, ip, whichfork); 273 if (error) 274 return error; 275 276 cur = xfs_bmbt_init_cursor(mp, tp, ip, whichfork); 277 error = xfs_btree_count_blocks(cur, &btblocks); 278 xfs_btree_del_cursor(cur, error); 279 if (error) 280 return error; 281 282 /* 283 * xfs_btree_count_blocks includes the root block contained in 284 * the inode fork in @btblocks, so subtract one because we're 285 * only interested in allocated disk blocks. 286 */ 287 *count += btblocks - 1; 288 289 fallthrough; 290 case XFS_DINODE_FMT_EXTENTS: 291 *nextents = xfs_bmap_count_leaves(ifp, count); 292 break; 293 } 294 295 return 0; 296 } 297 298 static int 299 xfs_getbmap_report_one( 300 struct xfs_inode *ip, 301 struct getbmapx *bmv, 302 struct kgetbmap *out, 303 int64_t bmv_end, 304 struct xfs_bmbt_irec *got) 305 { 306 struct kgetbmap *p = out + bmv->bmv_entries; 307 bool shared = false; 308 int error; 309 310 error = xfs_reflink_trim_around_shared(ip, got, &shared); 311 if (error) 312 return error; 313 314 if (isnullstartblock(got->br_startblock) || 315 got->br_startblock == DELAYSTARTBLOCK) { 316 /* 317 * Take the flush completion as being a point-in-time snapshot 318 * where there are no delalloc extents, and if any new ones 319 * have been created racily, just skip them as being 'after' 320 * the flush and so don't get reported. 321 */ 322 if (!(bmv->bmv_iflags & BMV_IF_DELALLOC)) 323 return 0; 324 325 p->bmv_oflags |= BMV_OF_DELALLOC; 326 p->bmv_block = -2; 327 } else { 328 p->bmv_block = xfs_fsb_to_db(ip, got->br_startblock); 329 } 330 331 if (got->br_state == XFS_EXT_UNWRITTEN && 332 (bmv->bmv_iflags & BMV_IF_PREALLOC)) 333 p->bmv_oflags |= BMV_OF_PREALLOC; 334 335 if (shared) 336 p->bmv_oflags |= BMV_OF_SHARED; 337 338 p->bmv_offset = XFS_FSB_TO_BB(ip->i_mount, got->br_startoff); 339 p->bmv_length = XFS_FSB_TO_BB(ip->i_mount, got->br_blockcount); 340 341 bmv->bmv_offset = p->bmv_offset + p->bmv_length; 342 bmv->bmv_length = max(0LL, bmv_end - bmv->bmv_offset); 343 bmv->bmv_entries++; 344 return 0; 345 } 346 347 static void 348 xfs_getbmap_report_hole( 349 struct xfs_inode *ip, 350 struct getbmapx *bmv, 351 struct kgetbmap *out, 352 int64_t bmv_end, 353 xfs_fileoff_t bno, 354 xfs_fileoff_t end) 355 { 356 struct kgetbmap *p = out + bmv->bmv_entries; 357 358 if (bmv->bmv_iflags & BMV_IF_NO_HOLES) 359 return; 360 361 p->bmv_block = -1; 362 p->bmv_offset = XFS_FSB_TO_BB(ip->i_mount, bno); 363 p->bmv_length = XFS_FSB_TO_BB(ip->i_mount, end - bno); 364 365 bmv->bmv_offset = p->bmv_offset + p->bmv_length; 366 bmv->bmv_length = max(0LL, bmv_end - bmv->bmv_offset); 367 bmv->bmv_entries++; 368 } 369 370 static inline bool 371 xfs_getbmap_full( 372 struct getbmapx *bmv) 373 { 374 return bmv->bmv_length == 0 || bmv->bmv_entries >= bmv->bmv_count - 1; 375 } 376 377 static bool 378 xfs_getbmap_next_rec( 379 struct xfs_bmbt_irec *rec, 380 xfs_fileoff_t total_end) 381 { 382 xfs_fileoff_t end = rec->br_startoff + rec->br_blockcount; 383 384 if (end == total_end) 385 return false; 386 387 rec->br_startoff += rec->br_blockcount; 388 if (!isnullstartblock(rec->br_startblock) && 389 rec->br_startblock != DELAYSTARTBLOCK) 390 rec->br_startblock += rec->br_blockcount; 391 rec->br_blockcount = total_end - end; 392 return true; 393 } 394 395 /* 396 * Get inode's extents as described in bmv, and format for output. 397 * Calls formatter to fill the user's buffer until all extents 398 * are mapped, until the passed-in bmv->bmv_count slots have 399 * been filled, or until the formatter short-circuits the loop, 400 * if it is tracking filled-in extents on its own. 401 */ 402 int /* error code */ 403 xfs_getbmap( 404 struct xfs_inode *ip, 405 struct getbmapx *bmv, /* user bmap structure */ 406 struct kgetbmap *out) 407 { 408 struct xfs_mount *mp = ip->i_mount; 409 int iflags = bmv->bmv_iflags; 410 int whichfork, lock, error = 0; 411 int64_t bmv_end, max_len; 412 xfs_fileoff_t bno, first_bno; 413 struct xfs_ifork *ifp; 414 struct xfs_bmbt_irec got, rec; 415 xfs_filblks_t len; 416 struct xfs_iext_cursor icur; 417 418 if (bmv->bmv_iflags & ~BMV_IF_VALID) 419 return -EINVAL; 420 #ifndef DEBUG 421 /* Only allow CoW fork queries if we're debugging. */ 422 if (iflags & BMV_IF_COWFORK) 423 return -EINVAL; 424 #endif 425 if ((iflags & BMV_IF_ATTRFORK) && (iflags & BMV_IF_COWFORK)) 426 return -EINVAL; 427 428 if (bmv->bmv_length < -1) 429 return -EINVAL; 430 bmv->bmv_entries = 0; 431 if (bmv->bmv_length == 0) 432 return 0; 433 434 if (iflags & BMV_IF_ATTRFORK) 435 whichfork = XFS_ATTR_FORK; 436 else if (iflags & BMV_IF_COWFORK) 437 whichfork = XFS_COW_FORK; 438 else 439 whichfork = XFS_DATA_FORK; 440 441 xfs_ilock(ip, XFS_IOLOCK_SHARED); 442 switch (whichfork) { 443 case XFS_ATTR_FORK: 444 lock = xfs_ilock_attr_map_shared(ip); 445 if (!xfs_inode_has_attr_fork(ip)) 446 goto out_unlock_ilock; 447 448 max_len = 1LL << 32; 449 break; 450 case XFS_COW_FORK: 451 lock = XFS_ILOCK_SHARED; 452 xfs_ilock(ip, lock); 453 454 /* No CoW fork? Just return */ 455 if (!xfs_ifork_ptr(ip, whichfork)) 456 goto out_unlock_ilock; 457 458 if (xfs_get_cowextsz_hint(ip)) 459 max_len = mp->m_super->s_maxbytes; 460 else 461 max_len = XFS_ISIZE(ip); 462 break; 463 case XFS_DATA_FORK: 464 if (!(iflags & BMV_IF_DELALLOC) && 465 (ip->i_delayed_blks || XFS_ISIZE(ip) > ip->i_disk_size)) { 466 error = filemap_write_and_wait(VFS_I(ip)->i_mapping); 467 if (error) 468 goto out_unlock_iolock; 469 470 /* 471 * Even after flushing the inode, there can still be 472 * delalloc blocks on the inode beyond EOF due to 473 * speculative preallocation. These are not removed 474 * until the release function is called or the inode 475 * is inactivated. Hence we cannot assert here that 476 * ip->i_delayed_blks == 0. 477 */ 478 } 479 480 if (xfs_get_extsz_hint(ip) || 481 (ip->i_diflags & 482 (XFS_DIFLAG_PREALLOC | XFS_DIFLAG_APPEND))) 483 max_len = mp->m_super->s_maxbytes; 484 else 485 max_len = XFS_ISIZE(ip); 486 487 lock = xfs_ilock_data_map_shared(ip); 488 break; 489 } 490 491 ifp = xfs_ifork_ptr(ip, whichfork); 492 493 switch (ifp->if_format) { 494 case XFS_DINODE_FMT_EXTENTS: 495 case XFS_DINODE_FMT_BTREE: 496 break; 497 case XFS_DINODE_FMT_LOCAL: 498 /* Local format inode forks report no extents. */ 499 goto out_unlock_ilock; 500 default: 501 error = -EINVAL; 502 goto out_unlock_ilock; 503 } 504 505 if (bmv->bmv_length == -1) { 506 max_len = XFS_FSB_TO_BB(mp, XFS_B_TO_FSB(mp, max_len)); 507 bmv->bmv_length = max(0LL, max_len - bmv->bmv_offset); 508 } 509 510 bmv_end = bmv->bmv_offset + bmv->bmv_length; 511 512 first_bno = bno = XFS_BB_TO_FSBT(mp, bmv->bmv_offset); 513 len = XFS_BB_TO_FSB(mp, bmv->bmv_length); 514 515 error = xfs_iread_extents(NULL, ip, whichfork); 516 if (error) 517 goto out_unlock_ilock; 518 519 if (!xfs_iext_lookup_extent(ip, ifp, bno, &icur, &got)) { 520 /* 521 * Report a whole-file hole if the delalloc flag is set to 522 * stay compatible with the old implementation. 523 */ 524 if (iflags & BMV_IF_DELALLOC) 525 xfs_getbmap_report_hole(ip, bmv, out, bmv_end, bno, 526 XFS_B_TO_FSB(mp, XFS_ISIZE(ip))); 527 goto out_unlock_ilock; 528 } 529 530 while (!xfs_getbmap_full(bmv)) { 531 xfs_trim_extent(&got, first_bno, len); 532 533 /* 534 * Report an entry for a hole if this extent doesn't directly 535 * follow the previous one. 536 */ 537 if (got.br_startoff > bno) { 538 xfs_getbmap_report_hole(ip, bmv, out, bmv_end, bno, 539 got.br_startoff); 540 if (xfs_getbmap_full(bmv)) 541 break; 542 } 543 544 /* 545 * In order to report shared extents accurately, we report each 546 * distinct shared / unshared part of a single bmbt record with 547 * an individual getbmapx record. 548 */ 549 bno = got.br_startoff + got.br_blockcount; 550 rec = got; 551 do { 552 error = xfs_getbmap_report_one(ip, bmv, out, bmv_end, 553 &rec); 554 if (error || xfs_getbmap_full(bmv)) 555 goto out_unlock_ilock; 556 } while (xfs_getbmap_next_rec(&rec, bno)); 557 558 if (!xfs_iext_next_extent(ifp, &icur, &got)) { 559 xfs_fileoff_t end = XFS_B_TO_FSB(mp, XFS_ISIZE(ip)); 560 561 if (bmv->bmv_entries > 0) 562 out[bmv->bmv_entries - 1].bmv_oflags |= 563 BMV_OF_LAST; 564 565 if (whichfork != XFS_ATTR_FORK && bno < end && 566 !xfs_getbmap_full(bmv)) { 567 xfs_getbmap_report_hole(ip, bmv, out, bmv_end, 568 bno, end); 569 } 570 break; 571 } 572 573 if (bno >= first_bno + len) 574 break; 575 } 576 577 out_unlock_ilock: 578 xfs_iunlock(ip, lock); 579 out_unlock_iolock: 580 xfs_iunlock(ip, XFS_IOLOCK_SHARED); 581 return error; 582 } 583 584 /* 585 * Dead simple method of punching delalyed allocation blocks from a range in 586 * the inode. This will always punch out both the start and end blocks, even 587 * if the ranges only partially overlap them, so it is up to the caller to 588 * ensure that partial blocks are not passed in. 589 */ 590 int 591 xfs_bmap_punch_delalloc_range( 592 struct xfs_inode *ip, 593 xfs_off_t start_byte, 594 xfs_off_t end_byte) 595 { 596 struct xfs_mount *mp = ip->i_mount; 597 struct xfs_ifork *ifp = &ip->i_df; 598 xfs_fileoff_t start_fsb = XFS_B_TO_FSBT(mp, start_byte); 599 xfs_fileoff_t end_fsb = XFS_B_TO_FSB(mp, end_byte); 600 struct xfs_bmbt_irec got, del; 601 struct xfs_iext_cursor icur; 602 int error = 0; 603 604 ASSERT(!xfs_need_iread_extents(ifp)); 605 606 xfs_ilock(ip, XFS_ILOCK_EXCL); 607 if (!xfs_iext_lookup_extent_before(ip, ifp, &end_fsb, &icur, &got)) 608 goto out_unlock; 609 610 while (got.br_startoff + got.br_blockcount > start_fsb) { 611 del = got; 612 xfs_trim_extent(&del, start_fsb, end_fsb - start_fsb); 613 614 /* 615 * A delete can push the cursor forward. Step back to the 616 * previous extent on non-delalloc or extents outside the 617 * target range. 618 */ 619 if (!del.br_blockcount || 620 !isnullstartblock(del.br_startblock)) { 621 if (!xfs_iext_prev_extent(ifp, &icur, &got)) 622 break; 623 continue; 624 } 625 626 error = xfs_bmap_del_extent_delay(ip, XFS_DATA_FORK, &icur, 627 &got, &del); 628 if (error || !xfs_iext_get_extent(ifp, &icur, &got)) 629 break; 630 } 631 632 out_unlock: 633 xfs_iunlock(ip, XFS_ILOCK_EXCL); 634 return error; 635 } 636 637 /* 638 * Test whether it is appropriate to check an inode for and free post EOF 639 * blocks. The 'force' parameter determines whether we should also consider 640 * regular files that are marked preallocated or append-only. 641 */ 642 bool 643 xfs_can_free_eofblocks( 644 struct xfs_inode *ip, 645 bool force) 646 { 647 struct xfs_bmbt_irec imap; 648 struct xfs_mount *mp = ip->i_mount; 649 xfs_fileoff_t end_fsb; 650 xfs_fileoff_t last_fsb; 651 int nimaps = 1; 652 int error; 653 654 /* 655 * Caller must either hold the exclusive io lock; or be inactivating 656 * the inode, which guarantees there are no other users of the inode. 657 */ 658 ASSERT(xfs_isilocked(ip, XFS_IOLOCK_EXCL) || 659 (VFS_I(ip)->i_state & I_FREEING)); 660 661 /* prealloc/delalloc exists only on regular files */ 662 if (!S_ISREG(VFS_I(ip)->i_mode)) 663 return false; 664 665 /* 666 * Zero sized files with no cached pages and delalloc blocks will not 667 * have speculative prealloc/delalloc blocks to remove. 668 */ 669 if (VFS_I(ip)->i_size == 0 && 670 VFS_I(ip)->i_mapping->nrpages == 0 && 671 ip->i_delayed_blks == 0) 672 return false; 673 674 /* If we haven't read in the extent list, then don't do it now. */ 675 if (xfs_need_iread_extents(&ip->i_df)) 676 return false; 677 678 /* 679 * Do not free real preallocated or append-only files unless the file 680 * has delalloc blocks and we are forced to remove them. 681 */ 682 if (ip->i_diflags & (XFS_DIFLAG_PREALLOC | XFS_DIFLAG_APPEND)) 683 if (!force || ip->i_delayed_blks == 0) 684 return false; 685 686 /* 687 * Do not try to free post-EOF blocks if EOF is beyond the end of the 688 * range supported by the page cache, because the truncation will loop 689 * forever. 690 */ 691 end_fsb = XFS_B_TO_FSB(mp, (xfs_ufsize_t)XFS_ISIZE(ip)); 692 if (XFS_IS_REALTIME_INODE(ip) && mp->m_sb.sb_rextsize > 1) 693 end_fsb = roundup_64(end_fsb, mp->m_sb.sb_rextsize); 694 last_fsb = XFS_B_TO_FSB(mp, mp->m_super->s_maxbytes); 695 if (last_fsb <= end_fsb) 696 return false; 697 698 /* 699 * Look up the mapping for the first block past EOF. If we can't find 700 * it, there's nothing to free. 701 */ 702 xfs_ilock(ip, XFS_ILOCK_SHARED); 703 error = xfs_bmapi_read(ip, end_fsb, last_fsb - end_fsb, &imap, &nimaps, 704 0); 705 xfs_iunlock(ip, XFS_ILOCK_SHARED); 706 if (error || nimaps == 0) 707 return false; 708 709 /* 710 * If there's a real mapping there or there are delayed allocation 711 * reservations, then we have post-EOF blocks to try to free. 712 */ 713 return imap.br_startblock != HOLESTARTBLOCK || ip->i_delayed_blks; 714 } 715 716 /* 717 * This is called to free any blocks beyond eof. The caller must hold 718 * IOLOCK_EXCL unless we are in the inode reclaim path and have the only 719 * reference to the inode. 720 */ 721 int 722 xfs_free_eofblocks( 723 struct xfs_inode *ip) 724 { 725 struct xfs_trans *tp; 726 struct xfs_mount *mp = ip->i_mount; 727 int error; 728 729 /* Attach the dquots to the inode up front. */ 730 error = xfs_qm_dqattach(ip); 731 if (error) 732 return error; 733 734 /* Wait on dio to ensure i_size has settled. */ 735 inode_dio_wait(VFS_I(ip)); 736 737 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_itruncate, 0, 0, 0, &tp); 738 if (error) { 739 ASSERT(xfs_is_shutdown(mp)); 740 return error; 741 } 742 743 xfs_ilock(ip, XFS_ILOCK_EXCL); 744 xfs_trans_ijoin(tp, ip, 0); 745 746 /* 747 * Do not update the on-disk file size. If we update the on-disk file 748 * size and then the system crashes before the contents of the file are 749 * flushed to disk then the files may be full of holes (ie NULL files 750 * bug). 751 */ 752 error = xfs_itruncate_extents_flags(&tp, ip, XFS_DATA_FORK, 753 XFS_ISIZE(ip), XFS_BMAPI_NODISCARD); 754 if (error) 755 goto err_cancel; 756 757 error = xfs_trans_commit(tp); 758 if (error) 759 goto out_unlock; 760 761 xfs_inode_clear_eofblocks_tag(ip); 762 goto out_unlock; 763 764 err_cancel: 765 /* 766 * If we get an error at this point we simply don't 767 * bother truncating the file. 768 */ 769 xfs_trans_cancel(tp); 770 out_unlock: 771 xfs_iunlock(ip, XFS_ILOCK_EXCL); 772 return error; 773 } 774 775 int 776 xfs_alloc_file_space( 777 struct xfs_inode *ip, 778 xfs_off_t offset, 779 xfs_off_t len) 780 { 781 xfs_mount_t *mp = ip->i_mount; 782 xfs_off_t count; 783 xfs_filblks_t allocated_fsb; 784 xfs_filblks_t allocatesize_fsb; 785 xfs_extlen_t extsz, temp; 786 xfs_fileoff_t startoffset_fsb; 787 xfs_fileoff_t endoffset_fsb; 788 int nimaps; 789 int rt; 790 xfs_trans_t *tp; 791 xfs_bmbt_irec_t imaps[1], *imapp; 792 int error; 793 794 trace_xfs_alloc_file_space(ip); 795 796 if (xfs_is_shutdown(mp)) 797 return -EIO; 798 799 error = xfs_qm_dqattach(ip); 800 if (error) 801 return error; 802 803 if (len <= 0) 804 return -EINVAL; 805 806 rt = XFS_IS_REALTIME_INODE(ip); 807 extsz = xfs_get_extsz_hint(ip); 808 809 count = len; 810 imapp = &imaps[0]; 811 nimaps = 1; 812 startoffset_fsb = XFS_B_TO_FSBT(mp, offset); 813 endoffset_fsb = XFS_B_TO_FSB(mp, offset + count); 814 allocatesize_fsb = endoffset_fsb - startoffset_fsb; 815 816 /* 817 * Allocate file space until done or until there is an error 818 */ 819 while (allocatesize_fsb && !error) { 820 xfs_fileoff_t s, e; 821 unsigned int dblocks, rblocks, resblks; 822 823 /* 824 * Determine space reservations for data/realtime. 825 */ 826 if (unlikely(extsz)) { 827 s = startoffset_fsb; 828 do_div(s, extsz); 829 s *= extsz; 830 e = startoffset_fsb + allocatesize_fsb; 831 div_u64_rem(startoffset_fsb, extsz, &temp); 832 if (temp) 833 e += temp; 834 div_u64_rem(e, extsz, &temp); 835 if (temp) 836 e += extsz - temp; 837 } else { 838 s = 0; 839 e = allocatesize_fsb; 840 } 841 842 /* 843 * The transaction reservation is limited to a 32-bit block 844 * count, hence we need to limit the number of blocks we are 845 * trying to reserve to avoid an overflow. We can't allocate 846 * more than @nimaps extents, and an extent is limited on disk 847 * to XFS_BMBT_MAX_EXTLEN (21 bits), so use that to enforce the 848 * limit. 849 */ 850 resblks = min_t(xfs_fileoff_t, (e - s), 851 (XFS_MAX_BMBT_EXTLEN * nimaps)); 852 if (unlikely(rt)) { 853 dblocks = XFS_DIOSTRAT_SPACE_RES(mp, 0); 854 rblocks = resblks; 855 } else { 856 dblocks = XFS_DIOSTRAT_SPACE_RES(mp, resblks); 857 rblocks = 0; 858 } 859 860 error = xfs_trans_alloc_inode(ip, &M_RES(mp)->tr_write, 861 dblocks, rblocks, false, &tp); 862 if (error) 863 break; 864 865 error = xfs_iext_count_may_overflow(ip, XFS_DATA_FORK, 866 XFS_IEXT_ADD_NOSPLIT_CNT); 867 if (error == -EFBIG) 868 error = xfs_iext_count_upgrade(tp, ip, 869 XFS_IEXT_ADD_NOSPLIT_CNT); 870 if (error) 871 goto error; 872 873 error = xfs_bmapi_write(tp, ip, startoffset_fsb, 874 allocatesize_fsb, XFS_BMAPI_PREALLOC, 0, imapp, 875 &nimaps); 876 if (error) 877 goto error; 878 879 ip->i_diflags |= XFS_DIFLAG_PREALLOC; 880 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE); 881 882 error = xfs_trans_commit(tp); 883 xfs_iunlock(ip, XFS_ILOCK_EXCL); 884 if (error) 885 break; 886 887 allocated_fsb = imapp->br_blockcount; 888 889 if (nimaps == 0) { 890 error = -ENOSPC; 891 break; 892 } 893 894 startoffset_fsb += allocated_fsb; 895 allocatesize_fsb -= allocated_fsb; 896 } 897 898 return error; 899 900 error: 901 xfs_trans_cancel(tp); 902 xfs_iunlock(ip, XFS_ILOCK_EXCL); 903 return error; 904 } 905 906 static int 907 xfs_unmap_extent( 908 struct xfs_inode *ip, 909 xfs_fileoff_t startoffset_fsb, 910 xfs_filblks_t len_fsb, 911 int *done) 912 { 913 struct xfs_mount *mp = ip->i_mount; 914 struct xfs_trans *tp; 915 uint resblks = XFS_DIOSTRAT_SPACE_RES(mp, 0); 916 int error; 917 918 error = xfs_trans_alloc_inode(ip, &M_RES(mp)->tr_write, resblks, 0, 919 false, &tp); 920 if (error) 921 return error; 922 923 error = xfs_iext_count_may_overflow(ip, XFS_DATA_FORK, 924 XFS_IEXT_PUNCH_HOLE_CNT); 925 if (error == -EFBIG) 926 error = xfs_iext_count_upgrade(tp, ip, XFS_IEXT_PUNCH_HOLE_CNT); 927 if (error) 928 goto out_trans_cancel; 929 930 error = xfs_bunmapi(tp, ip, startoffset_fsb, len_fsb, 0, 2, done); 931 if (error) 932 goto out_trans_cancel; 933 934 error = xfs_trans_commit(tp); 935 out_unlock: 936 xfs_iunlock(ip, XFS_ILOCK_EXCL); 937 return error; 938 939 out_trans_cancel: 940 xfs_trans_cancel(tp); 941 goto out_unlock; 942 } 943 944 /* Caller must first wait for the completion of any pending DIOs if required. */ 945 int 946 xfs_flush_unmap_range( 947 struct xfs_inode *ip, 948 xfs_off_t offset, 949 xfs_off_t len) 950 { 951 struct xfs_mount *mp = ip->i_mount; 952 struct inode *inode = VFS_I(ip); 953 xfs_off_t rounding, start, end; 954 int error; 955 956 rounding = max_t(xfs_off_t, mp->m_sb.sb_blocksize, PAGE_SIZE); 957 start = round_down(offset, rounding); 958 end = round_up(offset + len, rounding) - 1; 959 960 error = filemap_write_and_wait_range(inode->i_mapping, start, end); 961 if (error) 962 return error; 963 truncate_pagecache_range(inode, start, end); 964 return 0; 965 } 966 967 int 968 xfs_free_file_space( 969 struct xfs_inode *ip, 970 xfs_off_t offset, 971 xfs_off_t len) 972 { 973 struct xfs_mount *mp = ip->i_mount; 974 xfs_fileoff_t startoffset_fsb; 975 xfs_fileoff_t endoffset_fsb; 976 int done = 0, error; 977 978 trace_xfs_free_file_space(ip); 979 980 error = xfs_qm_dqattach(ip); 981 if (error) 982 return error; 983 984 if (len <= 0) /* if nothing being freed */ 985 return 0; 986 987 startoffset_fsb = XFS_B_TO_FSB(mp, offset); 988 endoffset_fsb = XFS_B_TO_FSBT(mp, offset + len); 989 990 /* We can only free complete realtime extents. */ 991 if (XFS_IS_REALTIME_INODE(ip) && mp->m_sb.sb_rextsize > 1) { 992 startoffset_fsb = roundup_64(startoffset_fsb, 993 mp->m_sb.sb_rextsize); 994 endoffset_fsb = rounddown_64(endoffset_fsb, 995 mp->m_sb.sb_rextsize); 996 } 997 998 /* 999 * Need to zero the stuff we're not freeing, on disk. 1000 */ 1001 if (endoffset_fsb > startoffset_fsb) { 1002 while (!done) { 1003 error = xfs_unmap_extent(ip, startoffset_fsb, 1004 endoffset_fsb - startoffset_fsb, &done); 1005 if (error) 1006 return error; 1007 } 1008 } 1009 1010 /* 1011 * Now that we've unmap all full blocks we'll have to zero out any 1012 * partial block at the beginning and/or end. xfs_zero_range is smart 1013 * enough to skip any holes, including those we just created, but we 1014 * must take care not to zero beyond EOF and enlarge i_size. 1015 */ 1016 if (offset >= XFS_ISIZE(ip)) 1017 return 0; 1018 if (offset + len > XFS_ISIZE(ip)) 1019 len = XFS_ISIZE(ip) - offset; 1020 error = xfs_zero_range(ip, offset, len, NULL); 1021 if (error) 1022 return error; 1023 1024 /* 1025 * If we zeroed right up to EOF and EOF straddles a page boundary we 1026 * must make sure that the post-EOF area is also zeroed because the 1027 * page could be mmap'd and xfs_zero_range doesn't do that for us. 1028 * Writeback of the eof page will do this, albeit clumsily. 1029 */ 1030 if (offset + len >= XFS_ISIZE(ip) && offset_in_page(offset + len) > 0) { 1031 error = filemap_write_and_wait_range(VFS_I(ip)->i_mapping, 1032 round_down(offset + len, PAGE_SIZE), LLONG_MAX); 1033 } 1034 1035 return error; 1036 } 1037 1038 static int 1039 xfs_prepare_shift( 1040 struct xfs_inode *ip, 1041 loff_t offset) 1042 { 1043 struct xfs_mount *mp = ip->i_mount; 1044 int error; 1045 1046 /* 1047 * Trim eofblocks to avoid shifting uninitialized post-eof preallocation 1048 * into the accessible region of the file. 1049 */ 1050 if (xfs_can_free_eofblocks(ip, true)) { 1051 error = xfs_free_eofblocks(ip); 1052 if (error) 1053 return error; 1054 } 1055 1056 /* 1057 * Shift operations must stabilize the start block offset boundary along 1058 * with the full range of the operation. If we don't, a COW writeback 1059 * completion could race with an insert, front merge with the start 1060 * extent (after split) during the shift and corrupt the file. Start 1061 * with the block just prior to the start to stabilize the boundary. 1062 */ 1063 offset = round_down(offset, mp->m_sb.sb_blocksize); 1064 if (offset) 1065 offset -= mp->m_sb.sb_blocksize; 1066 1067 /* 1068 * Writeback and invalidate cache for the remainder of the file as we're 1069 * about to shift down every extent from offset to EOF. 1070 */ 1071 error = xfs_flush_unmap_range(ip, offset, XFS_ISIZE(ip)); 1072 if (error) 1073 return error; 1074 1075 /* 1076 * Clean out anything hanging around in the cow fork now that 1077 * we've flushed all the dirty data out to disk to avoid having 1078 * CoW extents at the wrong offsets. 1079 */ 1080 if (xfs_inode_has_cow_data(ip)) { 1081 error = xfs_reflink_cancel_cow_range(ip, offset, NULLFILEOFF, 1082 true); 1083 if (error) 1084 return error; 1085 } 1086 1087 return 0; 1088 } 1089 1090 /* 1091 * xfs_collapse_file_space() 1092 * This routine frees disk space and shift extent for the given file. 1093 * The first thing we do is to free data blocks in the specified range 1094 * by calling xfs_free_file_space(). It would also sync dirty data 1095 * and invalidate page cache over the region on which collapse range 1096 * is working. And Shift extent records to the left to cover a hole. 1097 * RETURNS: 1098 * 0 on success 1099 * errno on error 1100 * 1101 */ 1102 int 1103 xfs_collapse_file_space( 1104 struct xfs_inode *ip, 1105 xfs_off_t offset, 1106 xfs_off_t len) 1107 { 1108 struct xfs_mount *mp = ip->i_mount; 1109 struct xfs_trans *tp; 1110 int error; 1111 xfs_fileoff_t next_fsb = XFS_B_TO_FSB(mp, offset + len); 1112 xfs_fileoff_t shift_fsb = XFS_B_TO_FSB(mp, len); 1113 bool done = false; 1114 1115 ASSERT(xfs_isilocked(ip, XFS_IOLOCK_EXCL)); 1116 ASSERT(xfs_isilocked(ip, XFS_MMAPLOCK_EXCL)); 1117 1118 trace_xfs_collapse_file_space(ip); 1119 1120 error = xfs_free_file_space(ip, offset, len); 1121 if (error) 1122 return error; 1123 1124 error = xfs_prepare_shift(ip, offset); 1125 if (error) 1126 return error; 1127 1128 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, 0, 0, 0, &tp); 1129 if (error) 1130 return error; 1131 1132 xfs_ilock(ip, XFS_ILOCK_EXCL); 1133 xfs_trans_ijoin(tp, ip, 0); 1134 1135 while (!done) { 1136 error = xfs_bmap_collapse_extents(tp, ip, &next_fsb, shift_fsb, 1137 &done); 1138 if (error) 1139 goto out_trans_cancel; 1140 if (done) 1141 break; 1142 1143 /* finish any deferred frees and roll the transaction */ 1144 error = xfs_defer_finish(&tp); 1145 if (error) 1146 goto out_trans_cancel; 1147 } 1148 1149 error = xfs_trans_commit(tp); 1150 xfs_iunlock(ip, XFS_ILOCK_EXCL); 1151 return error; 1152 1153 out_trans_cancel: 1154 xfs_trans_cancel(tp); 1155 xfs_iunlock(ip, XFS_ILOCK_EXCL); 1156 return error; 1157 } 1158 1159 /* 1160 * xfs_insert_file_space() 1161 * This routine create hole space by shifting extents for the given file. 1162 * The first thing we do is to sync dirty data and invalidate page cache 1163 * over the region on which insert range is working. And split an extent 1164 * to two extents at given offset by calling xfs_bmap_split_extent. 1165 * And shift all extent records which are laying between [offset, 1166 * last allocated extent] to the right to reserve hole range. 1167 * RETURNS: 1168 * 0 on success 1169 * errno on error 1170 */ 1171 int 1172 xfs_insert_file_space( 1173 struct xfs_inode *ip, 1174 loff_t offset, 1175 loff_t len) 1176 { 1177 struct xfs_mount *mp = ip->i_mount; 1178 struct xfs_trans *tp; 1179 int error; 1180 xfs_fileoff_t stop_fsb = XFS_B_TO_FSB(mp, offset); 1181 xfs_fileoff_t next_fsb = NULLFSBLOCK; 1182 xfs_fileoff_t shift_fsb = XFS_B_TO_FSB(mp, len); 1183 bool done = false; 1184 1185 ASSERT(xfs_isilocked(ip, XFS_IOLOCK_EXCL)); 1186 ASSERT(xfs_isilocked(ip, XFS_MMAPLOCK_EXCL)); 1187 1188 trace_xfs_insert_file_space(ip); 1189 1190 error = xfs_bmap_can_insert_extents(ip, stop_fsb, shift_fsb); 1191 if (error) 1192 return error; 1193 1194 error = xfs_prepare_shift(ip, offset); 1195 if (error) 1196 return error; 1197 1198 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, 1199 XFS_DIOSTRAT_SPACE_RES(mp, 0), 0, 0, &tp); 1200 if (error) 1201 return error; 1202 1203 xfs_ilock(ip, XFS_ILOCK_EXCL); 1204 xfs_trans_ijoin(tp, ip, 0); 1205 1206 error = xfs_iext_count_may_overflow(ip, XFS_DATA_FORK, 1207 XFS_IEXT_PUNCH_HOLE_CNT); 1208 if (error == -EFBIG) 1209 error = xfs_iext_count_upgrade(tp, ip, XFS_IEXT_PUNCH_HOLE_CNT); 1210 if (error) 1211 goto out_trans_cancel; 1212 1213 /* 1214 * The extent shifting code works on extent granularity. So, if stop_fsb 1215 * is not the starting block of extent, we need to split the extent at 1216 * stop_fsb. 1217 */ 1218 error = xfs_bmap_split_extent(tp, ip, stop_fsb); 1219 if (error) 1220 goto out_trans_cancel; 1221 1222 do { 1223 error = xfs_defer_finish(&tp); 1224 if (error) 1225 goto out_trans_cancel; 1226 1227 error = xfs_bmap_insert_extents(tp, ip, &next_fsb, shift_fsb, 1228 &done, stop_fsb); 1229 if (error) 1230 goto out_trans_cancel; 1231 } while (!done); 1232 1233 error = xfs_trans_commit(tp); 1234 xfs_iunlock(ip, XFS_ILOCK_EXCL); 1235 return error; 1236 1237 out_trans_cancel: 1238 xfs_trans_cancel(tp); 1239 xfs_iunlock(ip, XFS_ILOCK_EXCL); 1240 return error; 1241 } 1242 1243 /* 1244 * We need to check that the format of the data fork in the temporary inode is 1245 * valid for the target inode before doing the swap. This is not a problem with 1246 * attr1 because of the fixed fork offset, but attr2 has a dynamically sized 1247 * data fork depending on the space the attribute fork is taking so we can get 1248 * invalid formats on the target inode. 1249 * 1250 * E.g. target has space for 7 extents in extent format, temp inode only has 1251 * space for 6. If we defragment down to 7 extents, then the tmp format is a 1252 * btree, but when swapped it needs to be in extent format. Hence we can't just 1253 * blindly swap data forks on attr2 filesystems. 1254 * 1255 * Note that we check the swap in both directions so that we don't end up with 1256 * a corrupt temporary inode, either. 1257 * 1258 * Note that fixing the way xfs_fsr sets up the attribute fork in the source 1259 * inode will prevent this situation from occurring, so all we do here is 1260 * reject and log the attempt. basically we are putting the responsibility on 1261 * userspace to get this right. 1262 */ 1263 static int 1264 xfs_swap_extents_check_format( 1265 struct xfs_inode *ip, /* target inode */ 1266 struct xfs_inode *tip) /* tmp inode */ 1267 { 1268 struct xfs_ifork *ifp = &ip->i_df; 1269 struct xfs_ifork *tifp = &tip->i_df; 1270 1271 /* User/group/project quota ids must match if quotas are enforced. */ 1272 if (XFS_IS_QUOTA_ON(ip->i_mount) && 1273 (!uid_eq(VFS_I(ip)->i_uid, VFS_I(tip)->i_uid) || 1274 !gid_eq(VFS_I(ip)->i_gid, VFS_I(tip)->i_gid) || 1275 ip->i_projid != tip->i_projid)) 1276 return -EINVAL; 1277 1278 /* Should never get a local format */ 1279 if (ifp->if_format == XFS_DINODE_FMT_LOCAL || 1280 tifp->if_format == XFS_DINODE_FMT_LOCAL) 1281 return -EINVAL; 1282 1283 /* 1284 * if the target inode has less extents that then temporary inode then 1285 * why did userspace call us? 1286 */ 1287 if (ifp->if_nextents < tifp->if_nextents) 1288 return -EINVAL; 1289 1290 /* 1291 * If we have to use the (expensive) rmap swap method, we can 1292 * handle any number of extents and any format. 1293 */ 1294 if (xfs_has_rmapbt(ip->i_mount)) 1295 return 0; 1296 1297 /* 1298 * if the target inode is in extent form and the temp inode is in btree 1299 * form then we will end up with the target inode in the wrong format 1300 * as we already know there are less extents in the temp inode. 1301 */ 1302 if (ifp->if_format == XFS_DINODE_FMT_EXTENTS && 1303 tifp->if_format == XFS_DINODE_FMT_BTREE) 1304 return -EINVAL; 1305 1306 /* Check temp in extent form to max in target */ 1307 if (tifp->if_format == XFS_DINODE_FMT_EXTENTS && 1308 tifp->if_nextents > XFS_IFORK_MAXEXT(ip, XFS_DATA_FORK)) 1309 return -EINVAL; 1310 1311 /* Check target in extent form to max in temp */ 1312 if (ifp->if_format == XFS_DINODE_FMT_EXTENTS && 1313 ifp->if_nextents > XFS_IFORK_MAXEXT(tip, XFS_DATA_FORK)) 1314 return -EINVAL; 1315 1316 /* 1317 * If we are in a btree format, check that the temp root block will fit 1318 * in the target and that it has enough extents to be in btree format 1319 * in the target. 1320 * 1321 * Note that we have to be careful to allow btree->extent conversions 1322 * (a common defrag case) which will occur when the temp inode is in 1323 * extent format... 1324 */ 1325 if (tifp->if_format == XFS_DINODE_FMT_BTREE) { 1326 if (xfs_inode_has_attr_fork(ip) && 1327 XFS_BMAP_BMDR_SPACE(tifp->if_broot) > xfs_inode_fork_boff(ip)) 1328 return -EINVAL; 1329 if (tifp->if_nextents <= XFS_IFORK_MAXEXT(ip, XFS_DATA_FORK)) 1330 return -EINVAL; 1331 } 1332 1333 /* Reciprocal target->temp btree format checks */ 1334 if (ifp->if_format == XFS_DINODE_FMT_BTREE) { 1335 if (xfs_inode_has_attr_fork(tip) && 1336 XFS_BMAP_BMDR_SPACE(ip->i_df.if_broot) > xfs_inode_fork_boff(tip)) 1337 return -EINVAL; 1338 if (ifp->if_nextents <= XFS_IFORK_MAXEXT(tip, XFS_DATA_FORK)) 1339 return -EINVAL; 1340 } 1341 1342 return 0; 1343 } 1344 1345 static int 1346 xfs_swap_extent_flush( 1347 struct xfs_inode *ip) 1348 { 1349 int error; 1350 1351 error = filemap_write_and_wait(VFS_I(ip)->i_mapping); 1352 if (error) 1353 return error; 1354 truncate_pagecache_range(VFS_I(ip), 0, -1); 1355 1356 /* Verify O_DIRECT for ftmp */ 1357 if (VFS_I(ip)->i_mapping->nrpages) 1358 return -EINVAL; 1359 return 0; 1360 } 1361 1362 /* 1363 * Move extents from one file to another, when rmap is enabled. 1364 */ 1365 STATIC int 1366 xfs_swap_extent_rmap( 1367 struct xfs_trans **tpp, 1368 struct xfs_inode *ip, 1369 struct xfs_inode *tip) 1370 { 1371 struct xfs_trans *tp = *tpp; 1372 struct xfs_bmbt_irec irec; 1373 struct xfs_bmbt_irec uirec; 1374 struct xfs_bmbt_irec tirec; 1375 xfs_fileoff_t offset_fsb; 1376 xfs_fileoff_t end_fsb; 1377 xfs_filblks_t count_fsb; 1378 int error; 1379 xfs_filblks_t ilen; 1380 xfs_filblks_t rlen; 1381 int nimaps; 1382 uint64_t tip_flags2; 1383 1384 /* 1385 * If the source file has shared blocks, we must flag the donor 1386 * file as having shared blocks so that we get the shared-block 1387 * rmap functions when we go to fix up the rmaps. The flags 1388 * will be switch for reals later. 1389 */ 1390 tip_flags2 = tip->i_diflags2; 1391 if (ip->i_diflags2 & XFS_DIFLAG2_REFLINK) 1392 tip->i_diflags2 |= XFS_DIFLAG2_REFLINK; 1393 1394 offset_fsb = 0; 1395 end_fsb = XFS_B_TO_FSB(ip->i_mount, i_size_read(VFS_I(ip))); 1396 count_fsb = (xfs_filblks_t)(end_fsb - offset_fsb); 1397 1398 while (count_fsb) { 1399 /* Read extent from the donor file */ 1400 nimaps = 1; 1401 error = xfs_bmapi_read(tip, offset_fsb, count_fsb, &tirec, 1402 &nimaps, 0); 1403 if (error) 1404 goto out; 1405 ASSERT(nimaps == 1); 1406 ASSERT(tirec.br_startblock != DELAYSTARTBLOCK); 1407 1408 trace_xfs_swap_extent_rmap_remap(tip, &tirec); 1409 ilen = tirec.br_blockcount; 1410 1411 /* Unmap the old blocks in the source file. */ 1412 while (tirec.br_blockcount) { 1413 ASSERT(tp->t_highest_agno == NULLAGNUMBER); 1414 trace_xfs_swap_extent_rmap_remap_piece(tip, &tirec); 1415 1416 /* Read extent from the source file */ 1417 nimaps = 1; 1418 error = xfs_bmapi_read(ip, tirec.br_startoff, 1419 tirec.br_blockcount, &irec, 1420 &nimaps, 0); 1421 if (error) 1422 goto out; 1423 ASSERT(nimaps == 1); 1424 ASSERT(tirec.br_startoff == irec.br_startoff); 1425 trace_xfs_swap_extent_rmap_remap_piece(ip, &irec); 1426 1427 /* Trim the extent. */ 1428 uirec = tirec; 1429 uirec.br_blockcount = rlen = min_t(xfs_filblks_t, 1430 tirec.br_blockcount, 1431 irec.br_blockcount); 1432 trace_xfs_swap_extent_rmap_remap_piece(tip, &uirec); 1433 1434 if (xfs_bmap_is_real_extent(&uirec)) { 1435 error = xfs_iext_count_may_overflow(ip, 1436 XFS_DATA_FORK, 1437 XFS_IEXT_SWAP_RMAP_CNT); 1438 if (error == -EFBIG) 1439 error = xfs_iext_count_upgrade(tp, ip, 1440 XFS_IEXT_SWAP_RMAP_CNT); 1441 if (error) 1442 goto out; 1443 } 1444 1445 if (xfs_bmap_is_real_extent(&irec)) { 1446 error = xfs_iext_count_may_overflow(tip, 1447 XFS_DATA_FORK, 1448 XFS_IEXT_SWAP_RMAP_CNT); 1449 if (error == -EFBIG) 1450 error = xfs_iext_count_upgrade(tp, ip, 1451 XFS_IEXT_SWAP_RMAP_CNT); 1452 if (error) 1453 goto out; 1454 } 1455 1456 /* Remove the mapping from the donor file. */ 1457 xfs_bmap_unmap_extent(tp, tip, &uirec); 1458 1459 /* Remove the mapping from the source file. */ 1460 xfs_bmap_unmap_extent(tp, ip, &irec); 1461 1462 /* Map the donor file's blocks into the source file. */ 1463 xfs_bmap_map_extent(tp, ip, &uirec); 1464 1465 /* Map the source file's blocks into the donor file. */ 1466 xfs_bmap_map_extent(tp, tip, &irec); 1467 1468 error = xfs_defer_finish(tpp); 1469 tp = *tpp; 1470 if (error) 1471 goto out; 1472 1473 tirec.br_startoff += rlen; 1474 if (tirec.br_startblock != HOLESTARTBLOCK && 1475 tirec.br_startblock != DELAYSTARTBLOCK) 1476 tirec.br_startblock += rlen; 1477 tirec.br_blockcount -= rlen; 1478 } 1479 1480 /* Roll on... */ 1481 count_fsb -= ilen; 1482 offset_fsb += ilen; 1483 } 1484 1485 tip->i_diflags2 = tip_flags2; 1486 return 0; 1487 1488 out: 1489 trace_xfs_swap_extent_rmap_error(ip, error, _RET_IP_); 1490 tip->i_diflags2 = tip_flags2; 1491 return error; 1492 } 1493 1494 /* Swap the extents of two files by swapping data forks. */ 1495 STATIC int 1496 xfs_swap_extent_forks( 1497 struct xfs_trans *tp, 1498 struct xfs_inode *ip, 1499 struct xfs_inode *tip, 1500 int *src_log_flags, 1501 int *target_log_flags) 1502 { 1503 xfs_filblks_t aforkblks = 0; 1504 xfs_filblks_t taforkblks = 0; 1505 xfs_extnum_t junk; 1506 uint64_t tmp; 1507 int error; 1508 1509 /* 1510 * Count the number of extended attribute blocks 1511 */ 1512 if (xfs_inode_has_attr_fork(ip) && ip->i_af.if_nextents > 0 && 1513 ip->i_af.if_format != XFS_DINODE_FMT_LOCAL) { 1514 error = xfs_bmap_count_blocks(tp, ip, XFS_ATTR_FORK, &junk, 1515 &aforkblks); 1516 if (error) 1517 return error; 1518 } 1519 if (xfs_inode_has_attr_fork(tip) && tip->i_af.if_nextents > 0 && 1520 tip->i_af.if_format != XFS_DINODE_FMT_LOCAL) { 1521 error = xfs_bmap_count_blocks(tp, tip, XFS_ATTR_FORK, &junk, 1522 &taforkblks); 1523 if (error) 1524 return error; 1525 } 1526 1527 /* 1528 * Btree format (v3) inodes have the inode number stamped in the bmbt 1529 * block headers. We can't start changing the bmbt blocks until the 1530 * inode owner change is logged so recovery does the right thing in the 1531 * event of a crash. Set the owner change log flags now and leave the 1532 * bmbt scan as the last step. 1533 */ 1534 if (xfs_has_v3inodes(ip->i_mount)) { 1535 if (ip->i_df.if_format == XFS_DINODE_FMT_BTREE) 1536 (*target_log_flags) |= XFS_ILOG_DOWNER; 1537 if (tip->i_df.if_format == XFS_DINODE_FMT_BTREE) 1538 (*src_log_flags) |= XFS_ILOG_DOWNER; 1539 } 1540 1541 /* 1542 * Swap the data forks of the inodes 1543 */ 1544 swap(ip->i_df, tip->i_df); 1545 1546 /* 1547 * Fix the on-disk inode values 1548 */ 1549 tmp = (uint64_t)ip->i_nblocks; 1550 ip->i_nblocks = tip->i_nblocks - taforkblks + aforkblks; 1551 tip->i_nblocks = tmp + taforkblks - aforkblks; 1552 1553 /* 1554 * The extents in the source inode could still contain speculative 1555 * preallocation beyond EOF (e.g. the file is open but not modified 1556 * while defrag is in progress). In that case, we need to copy over the 1557 * number of delalloc blocks the data fork in the source inode is 1558 * tracking beyond EOF so that when the fork is truncated away when the 1559 * temporary inode is unlinked we don't underrun the i_delayed_blks 1560 * counter on that inode. 1561 */ 1562 ASSERT(tip->i_delayed_blks == 0); 1563 tip->i_delayed_blks = ip->i_delayed_blks; 1564 ip->i_delayed_blks = 0; 1565 1566 switch (ip->i_df.if_format) { 1567 case XFS_DINODE_FMT_EXTENTS: 1568 (*src_log_flags) |= XFS_ILOG_DEXT; 1569 break; 1570 case XFS_DINODE_FMT_BTREE: 1571 ASSERT(!xfs_has_v3inodes(ip->i_mount) || 1572 (*src_log_flags & XFS_ILOG_DOWNER)); 1573 (*src_log_flags) |= XFS_ILOG_DBROOT; 1574 break; 1575 } 1576 1577 switch (tip->i_df.if_format) { 1578 case XFS_DINODE_FMT_EXTENTS: 1579 (*target_log_flags) |= XFS_ILOG_DEXT; 1580 break; 1581 case XFS_DINODE_FMT_BTREE: 1582 (*target_log_flags) |= XFS_ILOG_DBROOT; 1583 ASSERT(!xfs_has_v3inodes(ip->i_mount) || 1584 (*target_log_flags & XFS_ILOG_DOWNER)); 1585 break; 1586 } 1587 1588 return 0; 1589 } 1590 1591 /* 1592 * Fix up the owners of the bmbt blocks to refer to the current inode. The 1593 * change owner scan attempts to order all modified buffers in the current 1594 * transaction. In the event of ordered buffer failure, the offending buffer is 1595 * physically logged as a fallback and the scan returns -EAGAIN. We must roll 1596 * the transaction in this case to replenish the fallback log reservation and 1597 * restart the scan. This process repeats until the scan completes. 1598 */ 1599 static int 1600 xfs_swap_change_owner( 1601 struct xfs_trans **tpp, 1602 struct xfs_inode *ip, 1603 struct xfs_inode *tmpip) 1604 { 1605 int error; 1606 struct xfs_trans *tp = *tpp; 1607 1608 do { 1609 error = xfs_bmbt_change_owner(tp, ip, XFS_DATA_FORK, ip->i_ino, 1610 NULL); 1611 /* success or fatal error */ 1612 if (error != -EAGAIN) 1613 break; 1614 1615 error = xfs_trans_roll(tpp); 1616 if (error) 1617 break; 1618 tp = *tpp; 1619 1620 /* 1621 * Redirty both inodes so they can relog and keep the log tail 1622 * moving forward. 1623 */ 1624 xfs_trans_ijoin(tp, ip, 0); 1625 xfs_trans_ijoin(tp, tmpip, 0); 1626 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE); 1627 xfs_trans_log_inode(tp, tmpip, XFS_ILOG_CORE); 1628 } while (true); 1629 1630 return error; 1631 } 1632 1633 int 1634 xfs_swap_extents( 1635 struct xfs_inode *ip, /* target inode */ 1636 struct xfs_inode *tip, /* tmp inode */ 1637 struct xfs_swapext *sxp) 1638 { 1639 struct xfs_mount *mp = ip->i_mount; 1640 struct xfs_trans *tp; 1641 struct xfs_bstat *sbp = &sxp->sx_stat; 1642 int src_log_flags, target_log_flags; 1643 int error = 0; 1644 uint64_t f; 1645 int resblks = 0; 1646 unsigned int flags = 0; 1647 1648 /* 1649 * Lock the inodes against other IO, page faults and truncate to 1650 * begin with. Then we can ensure the inodes are flushed and have no 1651 * page cache safely. Once we have done this we can take the ilocks and 1652 * do the rest of the checks. 1653 */ 1654 lock_two_nondirectories(VFS_I(ip), VFS_I(tip)); 1655 filemap_invalidate_lock_two(VFS_I(ip)->i_mapping, 1656 VFS_I(tip)->i_mapping); 1657 1658 /* Verify that both files have the same format */ 1659 if ((VFS_I(ip)->i_mode & S_IFMT) != (VFS_I(tip)->i_mode & S_IFMT)) { 1660 error = -EINVAL; 1661 goto out_unlock; 1662 } 1663 1664 /* Verify both files are either real-time or non-realtime */ 1665 if (XFS_IS_REALTIME_INODE(ip) != XFS_IS_REALTIME_INODE(tip)) { 1666 error = -EINVAL; 1667 goto out_unlock; 1668 } 1669 1670 error = xfs_qm_dqattach(ip); 1671 if (error) 1672 goto out_unlock; 1673 1674 error = xfs_qm_dqattach(tip); 1675 if (error) 1676 goto out_unlock; 1677 1678 error = xfs_swap_extent_flush(ip); 1679 if (error) 1680 goto out_unlock; 1681 error = xfs_swap_extent_flush(tip); 1682 if (error) 1683 goto out_unlock; 1684 1685 if (xfs_inode_has_cow_data(tip)) { 1686 error = xfs_reflink_cancel_cow_range(tip, 0, NULLFILEOFF, true); 1687 if (error) 1688 goto out_unlock; 1689 } 1690 1691 /* 1692 * Extent "swapping" with rmap requires a permanent reservation and 1693 * a block reservation because it's really just a remap operation 1694 * performed with log redo items! 1695 */ 1696 if (xfs_has_rmapbt(mp)) { 1697 int w = XFS_DATA_FORK; 1698 uint32_t ipnext = ip->i_df.if_nextents; 1699 uint32_t tipnext = tip->i_df.if_nextents; 1700 1701 /* 1702 * Conceptually this shouldn't affect the shape of either bmbt, 1703 * but since we atomically move extents one by one, we reserve 1704 * enough space to rebuild both trees. 1705 */ 1706 resblks = XFS_SWAP_RMAP_SPACE_RES(mp, ipnext, w); 1707 resblks += XFS_SWAP_RMAP_SPACE_RES(mp, tipnext, w); 1708 1709 /* 1710 * If either inode straddles a bmapbt block allocation boundary, 1711 * the rmapbt algorithm triggers repeated allocs and frees as 1712 * extents are remapped. This can exhaust the block reservation 1713 * prematurely and cause shutdown. Return freed blocks to the 1714 * transaction reservation to counter this behavior. 1715 */ 1716 flags |= XFS_TRANS_RES_FDBLKS; 1717 } 1718 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, resblks, 0, flags, 1719 &tp); 1720 if (error) 1721 goto out_unlock; 1722 1723 /* 1724 * Lock and join the inodes to the tansaction so that transaction commit 1725 * or cancel will unlock the inodes from this point onwards. 1726 */ 1727 xfs_lock_two_inodes(ip, XFS_ILOCK_EXCL, tip, XFS_ILOCK_EXCL); 1728 xfs_trans_ijoin(tp, ip, 0); 1729 xfs_trans_ijoin(tp, tip, 0); 1730 1731 1732 /* Verify all data are being swapped */ 1733 if (sxp->sx_offset != 0 || 1734 sxp->sx_length != ip->i_disk_size || 1735 sxp->sx_length != tip->i_disk_size) { 1736 error = -EFAULT; 1737 goto out_trans_cancel; 1738 } 1739 1740 trace_xfs_swap_extent_before(ip, 0); 1741 trace_xfs_swap_extent_before(tip, 1); 1742 1743 /* check inode formats now that data is flushed */ 1744 error = xfs_swap_extents_check_format(ip, tip); 1745 if (error) { 1746 xfs_notice(mp, 1747 "%s: inode 0x%llx format is incompatible for exchanging.", 1748 __func__, ip->i_ino); 1749 goto out_trans_cancel; 1750 } 1751 1752 /* 1753 * Compare the current change & modify times with that 1754 * passed in. If they differ, we abort this swap. 1755 * This is the mechanism used to ensure the calling 1756 * process that the file was not changed out from 1757 * under it. 1758 */ 1759 if ((sbp->bs_ctime.tv_sec != VFS_I(ip)->i_ctime.tv_sec) || 1760 (sbp->bs_ctime.tv_nsec != VFS_I(ip)->i_ctime.tv_nsec) || 1761 (sbp->bs_mtime.tv_sec != VFS_I(ip)->i_mtime.tv_sec) || 1762 (sbp->bs_mtime.tv_nsec != VFS_I(ip)->i_mtime.tv_nsec)) { 1763 error = -EBUSY; 1764 goto out_trans_cancel; 1765 } 1766 1767 /* 1768 * Note the trickiness in setting the log flags - we set the owner log 1769 * flag on the opposite inode (i.e. the inode we are setting the new 1770 * owner to be) because once we swap the forks and log that, log 1771 * recovery is going to see the fork as owned by the swapped inode, 1772 * not the pre-swapped inodes. 1773 */ 1774 src_log_flags = XFS_ILOG_CORE; 1775 target_log_flags = XFS_ILOG_CORE; 1776 1777 if (xfs_has_rmapbt(mp)) 1778 error = xfs_swap_extent_rmap(&tp, ip, tip); 1779 else 1780 error = xfs_swap_extent_forks(tp, ip, tip, &src_log_flags, 1781 &target_log_flags); 1782 if (error) 1783 goto out_trans_cancel; 1784 1785 /* Do we have to swap reflink flags? */ 1786 if ((ip->i_diflags2 & XFS_DIFLAG2_REFLINK) ^ 1787 (tip->i_diflags2 & XFS_DIFLAG2_REFLINK)) { 1788 f = ip->i_diflags2 & XFS_DIFLAG2_REFLINK; 1789 ip->i_diflags2 &= ~XFS_DIFLAG2_REFLINK; 1790 ip->i_diflags2 |= tip->i_diflags2 & XFS_DIFLAG2_REFLINK; 1791 tip->i_diflags2 &= ~XFS_DIFLAG2_REFLINK; 1792 tip->i_diflags2 |= f & XFS_DIFLAG2_REFLINK; 1793 } 1794 1795 /* Swap the cow forks. */ 1796 if (xfs_has_reflink(mp)) { 1797 ASSERT(!ip->i_cowfp || 1798 ip->i_cowfp->if_format == XFS_DINODE_FMT_EXTENTS); 1799 ASSERT(!tip->i_cowfp || 1800 tip->i_cowfp->if_format == XFS_DINODE_FMT_EXTENTS); 1801 1802 swap(ip->i_cowfp, tip->i_cowfp); 1803 1804 if (ip->i_cowfp && ip->i_cowfp->if_bytes) 1805 xfs_inode_set_cowblocks_tag(ip); 1806 else 1807 xfs_inode_clear_cowblocks_tag(ip); 1808 if (tip->i_cowfp && tip->i_cowfp->if_bytes) 1809 xfs_inode_set_cowblocks_tag(tip); 1810 else 1811 xfs_inode_clear_cowblocks_tag(tip); 1812 } 1813 1814 xfs_trans_log_inode(tp, ip, src_log_flags); 1815 xfs_trans_log_inode(tp, tip, target_log_flags); 1816 1817 /* 1818 * The extent forks have been swapped, but crc=1,rmapbt=0 filesystems 1819 * have inode number owner values in the bmbt blocks that still refer to 1820 * the old inode. Scan each bmbt to fix up the owner values with the 1821 * inode number of the current inode. 1822 */ 1823 if (src_log_flags & XFS_ILOG_DOWNER) { 1824 error = xfs_swap_change_owner(&tp, ip, tip); 1825 if (error) 1826 goto out_trans_cancel; 1827 } 1828 if (target_log_flags & XFS_ILOG_DOWNER) { 1829 error = xfs_swap_change_owner(&tp, tip, ip); 1830 if (error) 1831 goto out_trans_cancel; 1832 } 1833 1834 /* 1835 * If this is a synchronous mount, make sure that the 1836 * transaction goes to disk before returning to the user. 1837 */ 1838 if (xfs_has_wsync(mp)) 1839 xfs_trans_set_sync(tp); 1840 1841 error = xfs_trans_commit(tp); 1842 1843 trace_xfs_swap_extent_after(ip, 0); 1844 trace_xfs_swap_extent_after(tip, 1); 1845 1846 out_unlock_ilock: 1847 xfs_iunlock(ip, XFS_ILOCK_EXCL); 1848 xfs_iunlock(tip, XFS_ILOCK_EXCL); 1849 out_unlock: 1850 filemap_invalidate_unlock_two(VFS_I(ip)->i_mapping, 1851 VFS_I(tip)->i_mapping); 1852 unlock_two_nondirectories(VFS_I(ip), VFS_I(tip)); 1853 return error; 1854 1855 out_trans_cancel: 1856 xfs_trans_cancel(tp); 1857 goto out_unlock_ilock; 1858 } 1859