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