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 MAXEXTLEN 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 * MAXEXTLEN), 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 >= MAXEXTLEN) 129 ralen = MAXEXTLEN / 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 /* fall through */ 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 ifp = XFS_IFORK_PTR(ip, whichfork); 443 444 xfs_ilock(ip, XFS_IOLOCK_SHARED); 445 switch (whichfork) { 446 case XFS_ATTR_FORK: 447 if (!XFS_IFORK_Q(ip)) 448 goto out_unlock_iolock; 449 450 max_len = 1LL << 32; 451 lock = xfs_ilock_attr_map_shared(ip); 452 break; 453 case XFS_COW_FORK: 454 /* No CoW fork? Just return */ 455 if (!ifp) 456 goto out_unlock_iolock; 457 458 if (xfs_get_cowextsz_hint(ip)) 459 max_len = mp->m_super->s_maxbytes; 460 else 461 max_len = XFS_ISIZE(ip); 462 463 lock = XFS_ILOCK_SHARED; 464 xfs_ilock(ip, lock); 465 break; 466 case XFS_DATA_FORK: 467 if (!(iflags & BMV_IF_DELALLOC) && 468 (ip->i_delayed_blks || XFS_ISIZE(ip) > ip->i_disk_size)) { 469 error = filemap_write_and_wait(VFS_I(ip)->i_mapping); 470 if (error) 471 goto out_unlock_iolock; 472 473 /* 474 * Even after flushing the inode, there can still be 475 * delalloc blocks on the inode beyond EOF due to 476 * speculative preallocation. These are not removed 477 * until the release function is called or the inode 478 * is inactivated. Hence we cannot assert here that 479 * ip->i_delayed_blks == 0. 480 */ 481 } 482 483 if (xfs_get_extsz_hint(ip) || 484 (ip->i_diflags & 485 (XFS_DIFLAG_PREALLOC | XFS_DIFLAG_APPEND))) 486 max_len = mp->m_super->s_maxbytes; 487 else 488 max_len = XFS_ISIZE(ip); 489 490 lock = xfs_ilock_data_map_shared(ip); 491 break; 492 } 493 494 switch (ifp->if_format) { 495 case XFS_DINODE_FMT_EXTENTS: 496 case XFS_DINODE_FMT_BTREE: 497 break; 498 case XFS_DINODE_FMT_LOCAL: 499 /* Local format inode forks report no extents. */ 500 goto out_unlock_ilock; 501 default: 502 error = -EINVAL; 503 goto out_unlock_ilock; 504 } 505 506 if (bmv->bmv_length == -1) { 507 max_len = XFS_FSB_TO_BB(mp, XFS_B_TO_FSB(mp, max_len)); 508 bmv->bmv_length = max(0LL, max_len - bmv->bmv_offset); 509 } 510 511 bmv_end = bmv->bmv_offset + bmv->bmv_length; 512 513 first_bno = bno = XFS_BB_TO_FSBT(mp, bmv->bmv_offset); 514 len = XFS_BB_TO_FSB(mp, bmv->bmv_length); 515 516 error = xfs_iread_extents(NULL, ip, whichfork); 517 if (error) 518 goto out_unlock_ilock; 519 520 if (!xfs_iext_lookup_extent(ip, ifp, bno, &icur, &got)) { 521 /* 522 * Report a whole-file hole if the delalloc flag is set to 523 * stay compatible with the old implementation. 524 */ 525 if (iflags & BMV_IF_DELALLOC) 526 xfs_getbmap_report_hole(ip, bmv, out, bmv_end, bno, 527 XFS_B_TO_FSB(mp, XFS_ISIZE(ip))); 528 goto out_unlock_ilock; 529 } 530 531 while (!xfs_getbmap_full(bmv)) { 532 xfs_trim_extent(&got, first_bno, len); 533 534 /* 535 * Report an entry for a hole if this extent doesn't directly 536 * follow the previous one. 537 */ 538 if (got.br_startoff > bno) { 539 xfs_getbmap_report_hole(ip, bmv, out, bmv_end, bno, 540 got.br_startoff); 541 if (xfs_getbmap_full(bmv)) 542 break; 543 } 544 545 /* 546 * In order to report shared extents accurately, we report each 547 * distinct shared / unshared part of a single bmbt record with 548 * an individual getbmapx record. 549 */ 550 bno = got.br_startoff + got.br_blockcount; 551 rec = got; 552 do { 553 error = xfs_getbmap_report_one(ip, bmv, out, bmv_end, 554 &rec); 555 if (error || xfs_getbmap_full(bmv)) 556 goto out_unlock_ilock; 557 } while (xfs_getbmap_next_rec(&rec, bno)); 558 559 if (!xfs_iext_next_extent(ifp, &icur, &got)) { 560 xfs_fileoff_t end = XFS_B_TO_FSB(mp, XFS_ISIZE(ip)); 561 562 out[bmv->bmv_entries - 1].bmv_oflags |= BMV_OF_LAST; 563 564 if (whichfork != XFS_ATTR_FORK && bno < end && 565 !xfs_getbmap_full(bmv)) { 566 xfs_getbmap_report_hole(ip, bmv, out, bmv_end, 567 bno, end); 568 } 569 break; 570 } 571 572 if (bno >= first_bno + len) 573 break; 574 } 575 576 out_unlock_ilock: 577 xfs_iunlock(ip, lock); 578 out_unlock_iolock: 579 xfs_iunlock(ip, XFS_IOLOCK_SHARED); 580 return error; 581 } 582 583 /* 584 * Dead simple method of punching delalyed allocation blocks from a range in 585 * the inode. This will always punch out both the start and end blocks, even 586 * if the ranges only partially overlap them, so it is up to the caller to 587 * ensure that partial blocks are not passed in. 588 */ 589 int 590 xfs_bmap_punch_delalloc_range( 591 struct xfs_inode *ip, 592 xfs_fileoff_t start_fsb, 593 xfs_fileoff_t length) 594 { 595 struct xfs_ifork *ifp = &ip->i_df; 596 xfs_fileoff_t end_fsb = start_fsb + length; 597 struct xfs_bmbt_irec got, del; 598 struct xfs_iext_cursor icur; 599 int error = 0; 600 601 ASSERT(!xfs_need_iread_extents(ifp)); 602 603 xfs_ilock(ip, XFS_ILOCK_EXCL); 604 if (!xfs_iext_lookup_extent_before(ip, ifp, &end_fsb, &icur, &got)) 605 goto out_unlock; 606 607 while (got.br_startoff + got.br_blockcount > start_fsb) { 608 del = got; 609 xfs_trim_extent(&del, start_fsb, length); 610 611 /* 612 * A delete can push the cursor forward. Step back to the 613 * previous extent on non-delalloc or extents outside the 614 * target range. 615 */ 616 if (!del.br_blockcount || 617 !isnullstartblock(del.br_startblock)) { 618 if (!xfs_iext_prev_extent(ifp, &icur, &got)) 619 break; 620 continue; 621 } 622 623 error = xfs_bmap_del_extent_delay(ip, XFS_DATA_FORK, &icur, 624 &got, &del); 625 if (error || !xfs_iext_get_extent(ifp, &icur, &got)) 626 break; 627 } 628 629 out_unlock: 630 xfs_iunlock(ip, XFS_ILOCK_EXCL); 631 return error; 632 } 633 634 /* 635 * Test whether it is appropriate to check an inode for and free post EOF 636 * blocks. The 'force' parameter determines whether we should also consider 637 * regular files that are marked preallocated or append-only. 638 */ 639 bool 640 xfs_can_free_eofblocks( 641 struct xfs_inode *ip, 642 bool force) 643 { 644 struct xfs_bmbt_irec imap; 645 struct xfs_mount *mp = ip->i_mount; 646 xfs_fileoff_t end_fsb; 647 xfs_fileoff_t last_fsb; 648 int nimaps = 1; 649 int error; 650 651 /* 652 * Caller must either hold the exclusive io lock; or be inactivating 653 * the inode, which guarantees there are no other users of the inode. 654 */ 655 ASSERT(xfs_isilocked(ip, XFS_IOLOCK_EXCL) || 656 (VFS_I(ip)->i_state & I_FREEING)); 657 658 /* prealloc/delalloc exists only on regular files */ 659 if (!S_ISREG(VFS_I(ip)->i_mode)) 660 return false; 661 662 /* 663 * Zero sized files with no cached pages and delalloc blocks will not 664 * have speculative prealloc/delalloc blocks to remove. 665 */ 666 if (VFS_I(ip)->i_size == 0 && 667 VFS_I(ip)->i_mapping->nrpages == 0 && 668 ip->i_delayed_blks == 0) 669 return false; 670 671 /* If we haven't read in the extent list, then don't do it now. */ 672 if (xfs_need_iread_extents(&ip->i_df)) 673 return false; 674 675 /* 676 * Do not free real preallocated or append-only files unless the file 677 * has delalloc blocks and we are forced to remove them. 678 */ 679 if (ip->i_diflags & (XFS_DIFLAG_PREALLOC | XFS_DIFLAG_APPEND)) 680 if (!force || ip->i_delayed_blks == 0) 681 return false; 682 683 /* 684 * Do not try to free post-EOF blocks if EOF is beyond the end of the 685 * range supported by the page cache, because the truncation will loop 686 * forever. 687 */ 688 end_fsb = XFS_B_TO_FSB(mp, (xfs_ufsize_t)XFS_ISIZE(ip)); 689 last_fsb = XFS_B_TO_FSB(mp, mp->m_super->s_maxbytes); 690 if (last_fsb <= end_fsb) 691 return false; 692 693 /* 694 * Look up the mapping for the first block past EOF. If we can't find 695 * it, there's nothing to free. 696 */ 697 xfs_ilock(ip, XFS_ILOCK_SHARED); 698 error = xfs_bmapi_read(ip, end_fsb, last_fsb - end_fsb, &imap, &nimaps, 699 0); 700 xfs_iunlock(ip, XFS_ILOCK_SHARED); 701 if (error || nimaps == 0) 702 return false; 703 704 /* 705 * If there's a real mapping there or there are delayed allocation 706 * reservations, then we have post-EOF blocks to try to free. 707 */ 708 return imap.br_startblock != HOLESTARTBLOCK || ip->i_delayed_blks; 709 } 710 711 /* 712 * This is called to free any blocks beyond eof. The caller must hold 713 * IOLOCK_EXCL unless we are in the inode reclaim path and have the only 714 * reference to the inode. 715 */ 716 int 717 xfs_free_eofblocks( 718 struct xfs_inode *ip) 719 { 720 struct xfs_trans *tp; 721 struct xfs_mount *mp = ip->i_mount; 722 int error; 723 724 /* Attach the dquots to the inode up front. */ 725 error = xfs_qm_dqattach(ip); 726 if (error) 727 return error; 728 729 /* Wait on dio to ensure i_size has settled. */ 730 inode_dio_wait(VFS_I(ip)); 731 732 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_itruncate, 0, 0, 0, &tp); 733 if (error) { 734 ASSERT(XFS_FORCED_SHUTDOWN(mp)); 735 return error; 736 } 737 738 xfs_ilock(ip, XFS_ILOCK_EXCL); 739 xfs_trans_ijoin(tp, ip, 0); 740 741 /* 742 * Do not update the on-disk file size. If we update the on-disk file 743 * size and then the system crashes before the contents of the file are 744 * flushed to disk then the files may be full of holes (ie NULL files 745 * bug). 746 */ 747 error = xfs_itruncate_extents_flags(&tp, ip, XFS_DATA_FORK, 748 XFS_ISIZE(ip), XFS_BMAPI_NODISCARD); 749 if (error) 750 goto err_cancel; 751 752 error = xfs_trans_commit(tp); 753 if (error) 754 goto out_unlock; 755 756 xfs_inode_clear_eofblocks_tag(ip); 757 goto out_unlock; 758 759 err_cancel: 760 /* 761 * If we get an error at this point we simply don't 762 * bother truncating the file. 763 */ 764 xfs_trans_cancel(tp); 765 out_unlock: 766 xfs_iunlock(ip, XFS_ILOCK_EXCL); 767 return error; 768 } 769 770 int 771 xfs_alloc_file_space( 772 struct xfs_inode *ip, 773 xfs_off_t offset, 774 xfs_off_t len, 775 int alloc_type) 776 { 777 xfs_mount_t *mp = ip->i_mount; 778 xfs_off_t count; 779 xfs_filblks_t allocated_fsb; 780 xfs_filblks_t allocatesize_fsb; 781 xfs_extlen_t extsz, temp; 782 xfs_fileoff_t startoffset_fsb; 783 xfs_fileoff_t endoffset_fsb; 784 int nimaps; 785 int rt; 786 xfs_trans_t *tp; 787 xfs_bmbt_irec_t imaps[1], *imapp; 788 int error; 789 790 trace_xfs_alloc_file_space(ip); 791 792 if (XFS_FORCED_SHUTDOWN(mp)) 793 return -EIO; 794 795 error = xfs_qm_dqattach(ip); 796 if (error) 797 return error; 798 799 if (len <= 0) 800 return -EINVAL; 801 802 rt = XFS_IS_REALTIME_INODE(ip); 803 extsz = xfs_get_extsz_hint(ip); 804 805 count = len; 806 imapp = &imaps[0]; 807 nimaps = 1; 808 startoffset_fsb = XFS_B_TO_FSBT(mp, offset); 809 endoffset_fsb = XFS_B_TO_FSB(mp, offset + count); 810 allocatesize_fsb = endoffset_fsb - startoffset_fsb; 811 812 /* 813 * Allocate file space until done or until there is an error 814 */ 815 while (allocatesize_fsb && !error) { 816 xfs_fileoff_t s, e; 817 unsigned int dblocks, rblocks, resblks; 818 819 /* 820 * Determine space reservations for data/realtime. 821 */ 822 if (unlikely(extsz)) { 823 s = startoffset_fsb; 824 do_div(s, extsz); 825 s *= extsz; 826 e = startoffset_fsb + allocatesize_fsb; 827 div_u64_rem(startoffset_fsb, extsz, &temp); 828 if (temp) 829 e += temp; 830 div_u64_rem(e, extsz, &temp); 831 if (temp) 832 e += extsz - temp; 833 } else { 834 s = 0; 835 e = allocatesize_fsb; 836 } 837 838 /* 839 * The transaction reservation is limited to a 32-bit block 840 * count, hence we need to limit the number of blocks we are 841 * trying to reserve to avoid an overflow. We can't allocate 842 * more than @nimaps extents, and an extent is limited on disk 843 * to MAXEXTLEN (21 bits), so use that to enforce the limit. 844 */ 845 resblks = min_t(xfs_fileoff_t, (e - s), (MAXEXTLEN * nimaps)); 846 if (unlikely(rt)) { 847 dblocks = XFS_DIOSTRAT_SPACE_RES(mp, 0); 848 rblocks = resblks; 849 } else { 850 dblocks = XFS_DIOSTRAT_SPACE_RES(mp, resblks); 851 rblocks = 0; 852 } 853 854 /* 855 * Allocate and setup the transaction. 856 */ 857 error = xfs_trans_alloc_inode(ip, &M_RES(mp)->tr_write, 858 dblocks, rblocks, false, &tp); 859 if (error) 860 break; 861 862 error = xfs_iext_count_may_overflow(ip, XFS_DATA_FORK, 863 XFS_IEXT_ADD_NOSPLIT_CNT); 864 if (error) 865 goto error; 866 867 error = xfs_bmapi_write(tp, ip, startoffset_fsb, 868 allocatesize_fsb, alloc_type, 0, imapp, 869 &nimaps); 870 if (error) 871 goto error; 872 873 /* 874 * Complete the transaction 875 */ 876 error = xfs_trans_commit(tp); 877 xfs_iunlock(ip, XFS_ILOCK_EXCL); 878 if (error) 879 break; 880 881 allocated_fsb = imapp->br_blockcount; 882 883 if (nimaps == 0) { 884 error = -ENOSPC; 885 break; 886 } 887 888 startoffset_fsb += allocated_fsb; 889 allocatesize_fsb -= allocated_fsb; 890 } 891 892 return error; 893 894 error: 895 xfs_trans_cancel(tp); 896 xfs_iunlock(ip, XFS_ILOCK_EXCL); 897 return error; 898 } 899 900 static int 901 xfs_unmap_extent( 902 struct xfs_inode *ip, 903 xfs_fileoff_t startoffset_fsb, 904 xfs_filblks_t len_fsb, 905 int *done) 906 { 907 struct xfs_mount *mp = ip->i_mount; 908 struct xfs_trans *tp; 909 uint resblks = XFS_DIOSTRAT_SPACE_RES(mp, 0); 910 int error; 911 912 error = xfs_trans_alloc_inode(ip, &M_RES(mp)->tr_write, resblks, 0, 913 false, &tp); 914 if (error) 915 return error; 916 917 error = xfs_iext_count_may_overflow(ip, XFS_DATA_FORK, 918 XFS_IEXT_PUNCH_HOLE_CNT); 919 if (error) 920 goto out_trans_cancel; 921 922 error = xfs_bunmapi(tp, ip, startoffset_fsb, len_fsb, 0, 2, done); 923 if (error) 924 goto out_trans_cancel; 925 926 error = xfs_trans_commit(tp); 927 out_unlock: 928 xfs_iunlock(ip, XFS_ILOCK_EXCL); 929 return error; 930 931 out_trans_cancel: 932 xfs_trans_cancel(tp); 933 goto out_unlock; 934 } 935 936 /* Caller must first wait for the completion of any pending DIOs if required. */ 937 int 938 xfs_flush_unmap_range( 939 struct xfs_inode *ip, 940 xfs_off_t offset, 941 xfs_off_t len) 942 { 943 struct xfs_mount *mp = ip->i_mount; 944 struct inode *inode = VFS_I(ip); 945 xfs_off_t rounding, start, end; 946 int error; 947 948 rounding = max_t(xfs_off_t, 1 << mp->m_sb.sb_blocklog, PAGE_SIZE); 949 start = round_down(offset, rounding); 950 end = round_up(offset + len, rounding) - 1; 951 952 error = filemap_write_and_wait_range(inode->i_mapping, start, end); 953 if (error) 954 return error; 955 truncate_pagecache_range(inode, start, end); 956 return 0; 957 } 958 959 int 960 xfs_free_file_space( 961 struct xfs_inode *ip, 962 xfs_off_t offset, 963 xfs_off_t len) 964 { 965 struct xfs_mount *mp = ip->i_mount; 966 xfs_fileoff_t startoffset_fsb; 967 xfs_fileoff_t endoffset_fsb; 968 int done = 0, error; 969 970 trace_xfs_free_file_space(ip); 971 972 error = xfs_qm_dqattach(ip); 973 if (error) 974 return error; 975 976 if (len <= 0) /* if nothing being freed */ 977 return 0; 978 979 startoffset_fsb = XFS_B_TO_FSB(mp, offset); 980 endoffset_fsb = XFS_B_TO_FSBT(mp, offset + len); 981 982 /* We can only free complete realtime extents. */ 983 if (XFS_IS_REALTIME_INODE(ip) && mp->m_sb.sb_rextsize > 1) { 984 startoffset_fsb = roundup_64(startoffset_fsb, 985 mp->m_sb.sb_rextsize); 986 endoffset_fsb = rounddown_64(endoffset_fsb, 987 mp->m_sb.sb_rextsize); 988 } 989 990 /* 991 * Need to zero the stuff we're not freeing, on disk. 992 */ 993 if (endoffset_fsb > startoffset_fsb) { 994 while (!done) { 995 error = xfs_unmap_extent(ip, startoffset_fsb, 996 endoffset_fsb - startoffset_fsb, &done); 997 if (error) 998 return error; 999 } 1000 } 1001 1002 /* 1003 * Now that we've unmap all full blocks we'll have to zero out any 1004 * partial block at the beginning and/or end. iomap_zero_range is smart 1005 * enough to skip any holes, including those we just created, but we 1006 * must take care not to zero beyond EOF and enlarge i_size. 1007 */ 1008 if (offset >= XFS_ISIZE(ip)) 1009 return 0; 1010 if (offset + len > XFS_ISIZE(ip)) 1011 len = XFS_ISIZE(ip) - offset; 1012 error = iomap_zero_range(VFS_I(ip), offset, len, NULL, 1013 &xfs_buffered_write_iomap_ops); 1014 if (error) 1015 return error; 1016 1017 /* 1018 * If we zeroed right up to EOF and EOF straddles a page boundary we 1019 * must make sure that the post-EOF area is also zeroed because the 1020 * page could be mmap'd and iomap_zero_range doesn't do that for us. 1021 * Writeback of the eof page will do this, albeit clumsily. 1022 */ 1023 if (offset + len >= XFS_ISIZE(ip) && offset_in_page(offset + len) > 0) { 1024 error = filemap_write_and_wait_range(VFS_I(ip)->i_mapping, 1025 round_down(offset + len, PAGE_SIZE), LLONG_MAX); 1026 } 1027 1028 return error; 1029 } 1030 1031 static int 1032 xfs_prepare_shift( 1033 struct xfs_inode *ip, 1034 loff_t offset) 1035 { 1036 struct xfs_mount *mp = ip->i_mount; 1037 int error; 1038 1039 /* 1040 * Trim eofblocks to avoid shifting uninitialized post-eof preallocation 1041 * into the accessible region of the file. 1042 */ 1043 if (xfs_can_free_eofblocks(ip, true)) { 1044 error = xfs_free_eofblocks(ip); 1045 if (error) 1046 return error; 1047 } 1048 1049 /* 1050 * Shift operations must stabilize the start block offset boundary along 1051 * with the full range of the operation. If we don't, a COW writeback 1052 * completion could race with an insert, front merge with the start 1053 * extent (after split) during the shift and corrupt the file. Start 1054 * with the block just prior to the start to stabilize the boundary. 1055 */ 1056 offset = round_down(offset, 1 << mp->m_sb.sb_blocklog); 1057 if (offset) 1058 offset -= (1 << mp->m_sb.sb_blocklog); 1059 1060 /* 1061 * Writeback and invalidate cache for the remainder of the file as we're 1062 * about to shift down every extent from offset to EOF. 1063 */ 1064 error = xfs_flush_unmap_range(ip, offset, XFS_ISIZE(ip)); 1065 if (error) 1066 return error; 1067 1068 /* 1069 * Clean out anything hanging around in the cow fork now that 1070 * we've flushed all the dirty data out to disk to avoid having 1071 * CoW extents at the wrong offsets. 1072 */ 1073 if (xfs_inode_has_cow_data(ip)) { 1074 error = xfs_reflink_cancel_cow_range(ip, offset, NULLFILEOFF, 1075 true); 1076 if (error) 1077 return error; 1078 } 1079 1080 return 0; 1081 } 1082 1083 /* 1084 * xfs_collapse_file_space() 1085 * This routine frees disk space and shift extent for the given file. 1086 * The first thing we do is to free data blocks in the specified range 1087 * by calling xfs_free_file_space(). It would also sync dirty data 1088 * and invalidate page cache over the region on which collapse range 1089 * is working. And Shift extent records to the left to cover a hole. 1090 * RETURNS: 1091 * 0 on success 1092 * errno on error 1093 * 1094 */ 1095 int 1096 xfs_collapse_file_space( 1097 struct xfs_inode *ip, 1098 xfs_off_t offset, 1099 xfs_off_t len) 1100 { 1101 struct xfs_mount *mp = ip->i_mount; 1102 struct xfs_trans *tp; 1103 int error; 1104 xfs_fileoff_t next_fsb = XFS_B_TO_FSB(mp, offset + len); 1105 xfs_fileoff_t shift_fsb = XFS_B_TO_FSB(mp, len); 1106 bool done = false; 1107 1108 ASSERT(xfs_isilocked(ip, XFS_IOLOCK_EXCL)); 1109 ASSERT(xfs_isilocked(ip, XFS_MMAPLOCK_EXCL)); 1110 1111 trace_xfs_collapse_file_space(ip); 1112 1113 error = xfs_free_file_space(ip, offset, len); 1114 if (error) 1115 return error; 1116 1117 error = xfs_prepare_shift(ip, offset); 1118 if (error) 1119 return error; 1120 1121 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, 0, 0, 0, &tp); 1122 if (error) 1123 return error; 1124 1125 xfs_ilock(ip, XFS_ILOCK_EXCL); 1126 xfs_trans_ijoin(tp, ip, 0); 1127 1128 while (!done) { 1129 error = xfs_bmap_collapse_extents(tp, ip, &next_fsb, shift_fsb, 1130 &done); 1131 if (error) 1132 goto out_trans_cancel; 1133 if (done) 1134 break; 1135 1136 /* finish any deferred frees and roll the transaction */ 1137 error = xfs_defer_finish(&tp); 1138 if (error) 1139 goto out_trans_cancel; 1140 } 1141 1142 error = xfs_trans_commit(tp); 1143 xfs_iunlock(ip, XFS_ILOCK_EXCL); 1144 return error; 1145 1146 out_trans_cancel: 1147 xfs_trans_cancel(tp); 1148 xfs_iunlock(ip, XFS_ILOCK_EXCL); 1149 return error; 1150 } 1151 1152 /* 1153 * xfs_insert_file_space() 1154 * This routine create hole space by shifting extents for the given file. 1155 * The first thing we do is to sync dirty data and invalidate page cache 1156 * over the region on which insert range is working. And split an extent 1157 * to two extents at given offset by calling xfs_bmap_split_extent. 1158 * And shift all extent records which are laying between [offset, 1159 * last allocated extent] to the right to reserve hole range. 1160 * RETURNS: 1161 * 0 on success 1162 * errno on error 1163 */ 1164 int 1165 xfs_insert_file_space( 1166 struct xfs_inode *ip, 1167 loff_t offset, 1168 loff_t len) 1169 { 1170 struct xfs_mount *mp = ip->i_mount; 1171 struct xfs_trans *tp; 1172 int error; 1173 xfs_fileoff_t stop_fsb = XFS_B_TO_FSB(mp, offset); 1174 xfs_fileoff_t next_fsb = NULLFSBLOCK; 1175 xfs_fileoff_t shift_fsb = XFS_B_TO_FSB(mp, len); 1176 bool done = false; 1177 1178 ASSERT(xfs_isilocked(ip, XFS_IOLOCK_EXCL)); 1179 ASSERT(xfs_isilocked(ip, XFS_MMAPLOCK_EXCL)); 1180 1181 trace_xfs_insert_file_space(ip); 1182 1183 error = xfs_bmap_can_insert_extents(ip, stop_fsb, shift_fsb); 1184 if (error) 1185 return error; 1186 1187 error = xfs_prepare_shift(ip, offset); 1188 if (error) 1189 return error; 1190 1191 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, 1192 XFS_DIOSTRAT_SPACE_RES(mp, 0), 0, 0, &tp); 1193 if (error) 1194 return error; 1195 1196 xfs_ilock(ip, XFS_ILOCK_EXCL); 1197 xfs_trans_ijoin(tp, ip, 0); 1198 1199 error = xfs_iext_count_may_overflow(ip, XFS_DATA_FORK, 1200 XFS_IEXT_PUNCH_HOLE_CNT); 1201 if (error) 1202 goto out_trans_cancel; 1203 1204 /* 1205 * The extent shifting code works on extent granularity. So, if stop_fsb 1206 * is not the starting block of extent, we need to split the extent at 1207 * stop_fsb. 1208 */ 1209 error = xfs_bmap_split_extent(tp, ip, stop_fsb); 1210 if (error) 1211 goto out_trans_cancel; 1212 1213 do { 1214 error = xfs_defer_finish(&tp); 1215 if (error) 1216 goto out_trans_cancel; 1217 1218 error = xfs_bmap_insert_extents(tp, ip, &next_fsb, shift_fsb, 1219 &done, stop_fsb); 1220 if (error) 1221 goto out_trans_cancel; 1222 } while (!done); 1223 1224 error = xfs_trans_commit(tp); 1225 xfs_iunlock(ip, XFS_ILOCK_EXCL); 1226 return error; 1227 1228 out_trans_cancel: 1229 xfs_trans_cancel(tp); 1230 xfs_iunlock(ip, XFS_ILOCK_EXCL); 1231 return error; 1232 } 1233 1234 /* 1235 * We need to check that the format of the data fork in the temporary inode is 1236 * valid for the target inode before doing the swap. This is not a problem with 1237 * attr1 because of the fixed fork offset, but attr2 has a dynamically sized 1238 * data fork depending on the space the attribute fork is taking so we can get 1239 * invalid formats on the target inode. 1240 * 1241 * E.g. target has space for 7 extents in extent format, temp inode only has 1242 * space for 6. If we defragment down to 7 extents, then the tmp format is a 1243 * btree, but when swapped it needs to be in extent format. Hence we can't just 1244 * blindly swap data forks on attr2 filesystems. 1245 * 1246 * Note that we check the swap in both directions so that we don't end up with 1247 * a corrupt temporary inode, either. 1248 * 1249 * Note that fixing the way xfs_fsr sets up the attribute fork in the source 1250 * inode will prevent this situation from occurring, so all we do here is 1251 * reject and log the attempt. basically we are putting the responsibility on 1252 * userspace to get this right. 1253 */ 1254 static int 1255 xfs_swap_extents_check_format( 1256 struct xfs_inode *ip, /* target inode */ 1257 struct xfs_inode *tip) /* tmp inode */ 1258 { 1259 struct xfs_ifork *ifp = &ip->i_df; 1260 struct xfs_ifork *tifp = &tip->i_df; 1261 1262 /* User/group/project quota ids must match if quotas are enforced. */ 1263 if (XFS_IS_QUOTA_ON(ip->i_mount) && 1264 (!uid_eq(VFS_I(ip)->i_uid, VFS_I(tip)->i_uid) || 1265 !gid_eq(VFS_I(ip)->i_gid, VFS_I(tip)->i_gid) || 1266 ip->i_projid != tip->i_projid)) 1267 return -EINVAL; 1268 1269 /* Should never get a local format */ 1270 if (ifp->if_format == XFS_DINODE_FMT_LOCAL || 1271 tifp->if_format == XFS_DINODE_FMT_LOCAL) 1272 return -EINVAL; 1273 1274 /* 1275 * if the target inode has less extents that then temporary inode then 1276 * why did userspace call us? 1277 */ 1278 if (ifp->if_nextents < tifp->if_nextents) 1279 return -EINVAL; 1280 1281 /* 1282 * If we have to use the (expensive) rmap swap method, we can 1283 * handle any number of extents and any format. 1284 */ 1285 if (xfs_sb_version_hasrmapbt(&ip->i_mount->m_sb)) 1286 return 0; 1287 1288 /* 1289 * if the target inode is in extent form and the temp inode is in btree 1290 * form then we will end up with the target inode in the wrong format 1291 * as we already know there are less extents in the temp inode. 1292 */ 1293 if (ifp->if_format == XFS_DINODE_FMT_EXTENTS && 1294 tifp->if_format == XFS_DINODE_FMT_BTREE) 1295 return -EINVAL; 1296 1297 /* Check temp in extent form to max in target */ 1298 if (tifp->if_format == XFS_DINODE_FMT_EXTENTS && 1299 tifp->if_nextents > XFS_IFORK_MAXEXT(ip, XFS_DATA_FORK)) 1300 return -EINVAL; 1301 1302 /* Check target in extent form to max in temp */ 1303 if (ifp->if_format == XFS_DINODE_FMT_EXTENTS && 1304 ifp->if_nextents > XFS_IFORK_MAXEXT(tip, XFS_DATA_FORK)) 1305 return -EINVAL; 1306 1307 /* 1308 * If we are in a btree format, check that the temp root block will fit 1309 * in the target and that it has enough extents to be in btree format 1310 * in the target. 1311 * 1312 * Note that we have to be careful to allow btree->extent conversions 1313 * (a common defrag case) which will occur when the temp inode is in 1314 * extent format... 1315 */ 1316 if (tifp->if_format == XFS_DINODE_FMT_BTREE) { 1317 if (XFS_IFORK_Q(ip) && 1318 XFS_BMAP_BMDR_SPACE(tifp->if_broot) > XFS_IFORK_BOFF(ip)) 1319 return -EINVAL; 1320 if (tifp->if_nextents <= XFS_IFORK_MAXEXT(ip, XFS_DATA_FORK)) 1321 return -EINVAL; 1322 } 1323 1324 /* Reciprocal target->temp btree format checks */ 1325 if (ifp->if_format == XFS_DINODE_FMT_BTREE) { 1326 if (XFS_IFORK_Q(tip) && 1327 XFS_BMAP_BMDR_SPACE(ip->i_df.if_broot) > XFS_IFORK_BOFF(tip)) 1328 return -EINVAL; 1329 if (ifp->if_nextents <= XFS_IFORK_MAXEXT(tip, XFS_DATA_FORK)) 1330 return -EINVAL; 1331 } 1332 1333 return 0; 1334 } 1335 1336 static int 1337 xfs_swap_extent_flush( 1338 struct xfs_inode *ip) 1339 { 1340 int error; 1341 1342 error = filemap_write_and_wait(VFS_I(ip)->i_mapping); 1343 if (error) 1344 return error; 1345 truncate_pagecache_range(VFS_I(ip), 0, -1); 1346 1347 /* Verify O_DIRECT for ftmp */ 1348 if (VFS_I(ip)->i_mapping->nrpages) 1349 return -EINVAL; 1350 return 0; 1351 } 1352 1353 /* 1354 * Move extents from one file to another, when rmap is enabled. 1355 */ 1356 STATIC int 1357 xfs_swap_extent_rmap( 1358 struct xfs_trans **tpp, 1359 struct xfs_inode *ip, 1360 struct xfs_inode *tip) 1361 { 1362 struct xfs_trans *tp = *tpp; 1363 struct xfs_bmbt_irec irec; 1364 struct xfs_bmbt_irec uirec; 1365 struct xfs_bmbt_irec tirec; 1366 xfs_fileoff_t offset_fsb; 1367 xfs_fileoff_t end_fsb; 1368 xfs_filblks_t count_fsb; 1369 int error; 1370 xfs_filblks_t ilen; 1371 xfs_filblks_t rlen; 1372 int nimaps; 1373 uint64_t tip_flags2; 1374 1375 /* 1376 * If the source file has shared blocks, we must flag the donor 1377 * file as having shared blocks so that we get the shared-block 1378 * rmap functions when we go to fix up the rmaps. The flags 1379 * will be switch for reals later. 1380 */ 1381 tip_flags2 = tip->i_diflags2; 1382 if (ip->i_diflags2 & XFS_DIFLAG2_REFLINK) 1383 tip->i_diflags2 |= XFS_DIFLAG2_REFLINK; 1384 1385 offset_fsb = 0; 1386 end_fsb = XFS_B_TO_FSB(ip->i_mount, i_size_read(VFS_I(ip))); 1387 count_fsb = (xfs_filblks_t)(end_fsb - offset_fsb); 1388 1389 while (count_fsb) { 1390 /* Read extent from the donor file */ 1391 nimaps = 1; 1392 error = xfs_bmapi_read(tip, offset_fsb, count_fsb, &tirec, 1393 &nimaps, 0); 1394 if (error) 1395 goto out; 1396 ASSERT(nimaps == 1); 1397 ASSERT(tirec.br_startblock != DELAYSTARTBLOCK); 1398 1399 trace_xfs_swap_extent_rmap_remap(tip, &tirec); 1400 ilen = tirec.br_blockcount; 1401 1402 /* Unmap the old blocks in the source file. */ 1403 while (tirec.br_blockcount) { 1404 ASSERT(tp->t_firstblock == NULLFSBLOCK); 1405 trace_xfs_swap_extent_rmap_remap_piece(tip, &tirec); 1406 1407 /* Read extent from the source file */ 1408 nimaps = 1; 1409 error = xfs_bmapi_read(ip, tirec.br_startoff, 1410 tirec.br_blockcount, &irec, 1411 &nimaps, 0); 1412 if (error) 1413 goto out; 1414 ASSERT(nimaps == 1); 1415 ASSERT(tirec.br_startoff == irec.br_startoff); 1416 trace_xfs_swap_extent_rmap_remap_piece(ip, &irec); 1417 1418 /* Trim the extent. */ 1419 uirec = tirec; 1420 uirec.br_blockcount = rlen = min_t(xfs_filblks_t, 1421 tirec.br_blockcount, 1422 irec.br_blockcount); 1423 trace_xfs_swap_extent_rmap_remap_piece(tip, &uirec); 1424 1425 if (xfs_bmap_is_real_extent(&uirec)) { 1426 error = xfs_iext_count_may_overflow(ip, 1427 XFS_DATA_FORK, 1428 XFS_IEXT_SWAP_RMAP_CNT); 1429 if (error) 1430 goto out; 1431 } 1432 1433 if (xfs_bmap_is_real_extent(&irec)) { 1434 error = xfs_iext_count_may_overflow(tip, 1435 XFS_DATA_FORK, 1436 XFS_IEXT_SWAP_RMAP_CNT); 1437 if (error) 1438 goto out; 1439 } 1440 1441 /* Remove the mapping from the donor file. */ 1442 xfs_bmap_unmap_extent(tp, tip, &uirec); 1443 1444 /* Remove the mapping from the source file. */ 1445 xfs_bmap_unmap_extent(tp, ip, &irec); 1446 1447 /* Map the donor file's blocks into the source file. */ 1448 xfs_bmap_map_extent(tp, ip, &uirec); 1449 1450 /* Map the source file's blocks into the donor file. */ 1451 xfs_bmap_map_extent(tp, tip, &irec); 1452 1453 error = xfs_defer_finish(tpp); 1454 tp = *tpp; 1455 if (error) 1456 goto out; 1457 1458 tirec.br_startoff += rlen; 1459 if (tirec.br_startblock != HOLESTARTBLOCK && 1460 tirec.br_startblock != DELAYSTARTBLOCK) 1461 tirec.br_startblock += rlen; 1462 tirec.br_blockcount -= rlen; 1463 } 1464 1465 /* Roll on... */ 1466 count_fsb -= ilen; 1467 offset_fsb += ilen; 1468 } 1469 1470 tip->i_diflags2 = tip_flags2; 1471 return 0; 1472 1473 out: 1474 trace_xfs_swap_extent_rmap_error(ip, error, _RET_IP_); 1475 tip->i_diflags2 = tip_flags2; 1476 return error; 1477 } 1478 1479 /* Swap the extents of two files by swapping data forks. */ 1480 STATIC int 1481 xfs_swap_extent_forks( 1482 struct xfs_trans *tp, 1483 struct xfs_inode *ip, 1484 struct xfs_inode *tip, 1485 int *src_log_flags, 1486 int *target_log_flags) 1487 { 1488 xfs_filblks_t aforkblks = 0; 1489 xfs_filblks_t taforkblks = 0; 1490 xfs_extnum_t junk; 1491 uint64_t tmp; 1492 int error; 1493 1494 /* 1495 * Count the number of extended attribute blocks 1496 */ 1497 if (XFS_IFORK_Q(ip) && ip->i_afp->if_nextents > 0 && 1498 ip->i_afp->if_format != XFS_DINODE_FMT_LOCAL) { 1499 error = xfs_bmap_count_blocks(tp, ip, XFS_ATTR_FORK, &junk, 1500 &aforkblks); 1501 if (error) 1502 return error; 1503 } 1504 if (XFS_IFORK_Q(tip) && tip->i_afp->if_nextents > 0 && 1505 tip->i_afp->if_format != XFS_DINODE_FMT_LOCAL) { 1506 error = xfs_bmap_count_blocks(tp, tip, XFS_ATTR_FORK, &junk, 1507 &taforkblks); 1508 if (error) 1509 return error; 1510 } 1511 1512 /* 1513 * Btree format (v3) inodes have the inode number stamped in the bmbt 1514 * block headers. We can't start changing the bmbt blocks until the 1515 * inode owner change is logged so recovery does the right thing in the 1516 * event of a crash. Set the owner change log flags now and leave the 1517 * bmbt scan as the last step. 1518 */ 1519 if (xfs_sb_version_has_v3inode(&ip->i_mount->m_sb)) { 1520 if (ip->i_df.if_format == XFS_DINODE_FMT_BTREE) 1521 (*target_log_flags) |= XFS_ILOG_DOWNER; 1522 if (tip->i_df.if_format == XFS_DINODE_FMT_BTREE) 1523 (*src_log_flags) |= XFS_ILOG_DOWNER; 1524 } 1525 1526 /* 1527 * Swap the data forks of the inodes 1528 */ 1529 swap(ip->i_df, tip->i_df); 1530 1531 /* 1532 * Fix the on-disk inode values 1533 */ 1534 tmp = (uint64_t)ip->i_nblocks; 1535 ip->i_nblocks = tip->i_nblocks - taforkblks + aforkblks; 1536 tip->i_nblocks = tmp + taforkblks - aforkblks; 1537 1538 /* 1539 * The extents in the source inode could still contain speculative 1540 * preallocation beyond EOF (e.g. the file is open but not modified 1541 * while defrag is in progress). In that case, we need to copy over the 1542 * number of delalloc blocks the data fork in the source inode is 1543 * tracking beyond EOF so that when the fork is truncated away when the 1544 * temporary inode is unlinked we don't underrun the i_delayed_blks 1545 * counter on that inode. 1546 */ 1547 ASSERT(tip->i_delayed_blks == 0); 1548 tip->i_delayed_blks = ip->i_delayed_blks; 1549 ip->i_delayed_blks = 0; 1550 1551 switch (ip->i_df.if_format) { 1552 case XFS_DINODE_FMT_EXTENTS: 1553 (*src_log_flags) |= XFS_ILOG_DEXT; 1554 break; 1555 case XFS_DINODE_FMT_BTREE: 1556 ASSERT(!xfs_sb_version_has_v3inode(&ip->i_mount->m_sb) || 1557 (*src_log_flags & XFS_ILOG_DOWNER)); 1558 (*src_log_flags) |= XFS_ILOG_DBROOT; 1559 break; 1560 } 1561 1562 switch (tip->i_df.if_format) { 1563 case XFS_DINODE_FMT_EXTENTS: 1564 (*target_log_flags) |= XFS_ILOG_DEXT; 1565 break; 1566 case XFS_DINODE_FMT_BTREE: 1567 (*target_log_flags) |= XFS_ILOG_DBROOT; 1568 ASSERT(!xfs_sb_version_has_v3inode(&ip->i_mount->m_sb) || 1569 (*target_log_flags & XFS_ILOG_DOWNER)); 1570 break; 1571 } 1572 1573 return 0; 1574 } 1575 1576 /* 1577 * Fix up the owners of the bmbt blocks to refer to the current inode. The 1578 * change owner scan attempts to order all modified buffers in the current 1579 * transaction. In the event of ordered buffer failure, the offending buffer is 1580 * physically logged as a fallback and the scan returns -EAGAIN. We must roll 1581 * the transaction in this case to replenish the fallback log reservation and 1582 * restart the scan. This process repeats until the scan completes. 1583 */ 1584 static int 1585 xfs_swap_change_owner( 1586 struct xfs_trans **tpp, 1587 struct xfs_inode *ip, 1588 struct xfs_inode *tmpip) 1589 { 1590 int error; 1591 struct xfs_trans *tp = *tpp; 1592 1593 do { 1594 error = xfs_bmbt_change_owner(tp, ip, XFS_DATA_FORK, ip->i_ino, 1595 NULL); 1596 /* success or fatal error */ 1597 if (error != -EAGAIN) 1598 break; 1599 1600 error = xfs_trans_roll(tpp); 1601 if (error) 1602 break; 1603 tp = *tpp; 1604 1605 /* 1606 * Redirty both inodes so they can relog and keep the log tail 1607 * moving forward. 1608 */ 1609 xfs_trans_ijoin(tp, ip, 0); 1610 xfs_trans_ijoin(tp, tmpip, 0); 1611 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE); 1612 xfs_trans_log_inode(tp, tmpip, XFS_ILOG_CORE); 1613 } while (true); 1614 1615 return error; 1616 } 1617 1618 int 1619 xfs_swap_extents( 1620 struct xfs_inode *ip, /* target inode */ 1621 struct xfs_inode *tip, /* tmp inode */ 1622 struct xfs_swapext *sxp) 1623 { 1624 struct xfs_mount *mp = ip->i_mount; 1625 struct xfs_trans *tp; 1626 struct xfs_bstat *sbp = &sxp->sx_stat; 1627 int src_log_flags, target_log_flags; 1628 int error = 0; 1629 int lock_flags; 1630 uint64_t f; 1631 int resblks = 0; 1632 unsigned int flags = 0; 1633 1634 /* 1635 * Lock the inodes against other IO, page faults and truncate to 1636 * begin with. Then we can ensure the inodes are flushed and have no 1637 * page cache safely. Once we have done this we can take the ilocks and 1638 * do the rest of the checks. 1639 */ 1640 lock_two_nondirectories(VFS_I(ip), VFS_I(tip)); 1641 lock_flags = XFS_MMAPLOCK_EXCL; 1642 xfs_lock_two_inodes(ip, XFS_MMAPLOCK_EXCL, tip, XFS_MMAPLOCK_EXCL); 1643 1644 /* Verify that both files have the same format */ 1645 if ((VFS_I(ip)->i_mode & S_IFMT) != (VFS_I(tip)->i_mode & S_IFMT)) { 1646 error = -EINVAL; 1647 goto out_unlock; 1648 } 1649 1650 /* Verify both files are either real-time or non-realtime */ 1651 if (XFS_IS_REALTIME_INODE(ip) != XFS_IS_REALTIME_INODE(tip)) { 1652 error = -EINVAL; 1653 goto out_unlock; 1654 } 1655 1656 error = xfs_qm_dqattach(ip); 1657 if (error) 1658 goto out_unlock; 1659 1660 error = xfs_qm_dqattach(tip); 1661 if (error) 1662 goto out_unlock; 1663 1664 error = xfs_swap_extent_flush(ip); 1665 if (error) 1666 goto out_unlock; 1667 error = xfs_swap_extent_flush(tip); 1668 if (error) 1669 goto out_unlock; 1670 1671 if (xfs_inode_has_cow_data(tip)) { 1672 error = xfs_reflink_cancel_cow_range(tip, 0, NULLFILEOFF, true); 1673 if (error) 1674 goto out_unlock; 1675 } 1676 1677 /* 1678 * Extent "swapping" with rmap requires a permanent reservation and 1679 * a block reservation because it's really just a remap operation 1680 * performed with log redo items! 1681 */ 1682 if (xfs_sb_version_hasrmapbt(&mp->m_sb)) { 1683 int w = XFS_DATA_FORK; 1684 uint32_t ipnext = ip->i_df.if_nextents; 1685 uint32_t tipnext = tip->i_df.if_nextents; 1686 1687 /* 1688 * Conceptually this shouldn't affect the shape of either bmbt, 1689 * but since we atomically move extents one by one, we reserve 1690 * enough space to rebuild both trees. 1691 */ 1692 resblks = XFS_SWAP_RMAP_SPACE_RES(mp, ipnext, w); 1693 resblks += XFS_SWAP_RMAP_SPACE_RES(mp, tipnext, w); 1694 1695 /* 1696 * If either inode straddles a bmapbt block allocation boundary, 1697 * the rmapbt algorithm triggers repeated allocs and frees as 1698 * extents are remapped. This can exhaust the block reservation 1699 * prematurely and cause shutdown. Return freed blocks to the 1700 * transaction reservation to counter this behavior. 1701 */ 1702 flags |= XFS_TRANS_RES_FDBLKS; 1703 } 1704 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, resblks, 0, flags, 1705 &tp); 1706 if (error) 1707 goto out_unlock; 1708 1709 /* 1710 * Lock and join the inodes to the tansaction so that transaction commit 1711 * or cancel will unlock the inodes from this point onwards. 1712 */ 1713 xfs_lock_two_inodes(ip, XFS_ILOCK_EXCL, tip, XFS_ILOCK_EXCL); 1714 lock_flags |= XFS_ILOCK_EXCL; 1715 xfs_trans_ijoin(tp, ip, 0); 1716 xfs_trans_ijoin(tp, tip, 0); 1717 1718 1719 /* Verify all data are being swapped */ 1720 if (sxp->sx_offset != 0 || 1721 sxp->sx_length != ip->i_disk_size || 1722 sxp->sx_length != tip->i_disk_size) { 1723 error = -EFAULT; 1724 goto out_trans_cancel; 1725 } 1726 1727 trace_xfs_swap_extent_before(ip, 0); 1728 trace_xfs_swap_extent_before(tip, 1); 1729 1730 /* check inode formats now that data is flushed */ 1731 error = xfs_swap_extents_check_format(ip, tip); 1732 if (error) { 1733 xfs_notice(mp, 1734 "%s: inode 0x%llx format is incompatible for exchanging.", 1735 __func__, ip->i_ino); 1736 goto out_trans_cancel; 1737 } 1738 1739 /* 1740 * Compare the current change & modify times with that 1741 * passed in. If they differ, we abort this swap. 1742 * This is the mechanism used to ensure the calling 1743 * process that the file was not changed out from 1744 * under it. 1745 */ 1746 if ((sbp->bs_ctime.tv_sec != VFS_I(ip)->i_ctime.tv_sec) || 1747 (sbp->bs_ctime.tv_nsec != VFS_I(ip)->i_ctime.tv_nsec) || 1748 (sbp->bs_mtime.tv_sec != VFS_I(ip)->i_mtime.tv_sec) || 1749 (sbp->bs_mtime.tv_nsec != VFS_I(ip)->i_mtime.tv_nsec)) { 1750 error = -EBUSY; 1751 goto out_trans_cancel; 1752 } 1753 1754 /* 1755 * Note the trickiness in setting the log flags - we set the owner log 1756 * flag on the opposite inode (i.e. the inode we are setting the new 1757 * owner to be) because once we swap the forks and log that, log 1758 * recovery is going to see the fork as owned by the swapped inode, 1759 * not the pre-swapped inodes. 1760 */ 1761 src_log_flags = XFS_ILOG_CORE; 1762 target_log_flags = XFS_ILOG_CORE; 1763 1764 if (xfs_sb_version_hasrmapbt(&mp->m_sb)) 1765 error = xfs_swap_extent_rmap(&tp, ip, tip); 1766 else 1767 error = xfs_swap_extent_forks(tp, ip, tip, &src_log_flags, 1768 &target_log_flags); 1769 if (error) 1770 goto out_trans_cancel; 1771 1772 /* Do we have to swap reflink flags? */ 1773 if ((ip->i_diflags2 & XFS_DIFLAG2_REFLINK) ^ 1774 (tip->i_diflags2 & XFS_DIFLAG2_REFLINK)) { 1775 f = ip->i_diflags2 & XFS_DIFLAG2_REFLINK; 1776 ip->i_diflags2 &= ~XFS_DIFLAG2_REFLINK; 1777 ip->i_diflags2 |= tip->i_diflags2 & XFS_DIFLAG2_REFLINK; 1778 tip->i_diflags2 &= ~XFS_DIFLAG2_REFLINK; 1779 tip->i_diflags2 |= f & XFS_DIFLAG2_REFLINK; 1780 } 1781 1782 /* Swap the cow forks. */ 1783 if (xfs_sb_version_hasreflink(&mp->m_sb)) { 1784 ASSERT(!ip->i_cowfp || 1785 ip->i_cowfp->if_format == XFS_DINODE_FMT_EXTENTS); 1786 ASSERT(!tip->i_cowfp || 1787 tip->i_cowfp->if_format == XFS_DINODE_FMT_EXTENTS); 1788 1789 swap(ip->i_cowfp, tip->i_cowfp); 1790 1791 if (ip->i_cowfp && ip->i_cowfp->if_bytes) 1792 xfs_inode_set_cowblocks_tag(ip); 1793 else 1794 xfs_inode_clear_cowblocks_tag(ip); 1795 if (tip->i_cowfp && tip->i_cowfp->if_bytes) 1796 xfs_inode_set_cowblocks_tag(tip); 1797 else 1798 xfs_inode_clear_cowblocks_tag(tip); 1799 } 1800 1801 xfs_trans_log_inode(tp, ip, src_log_flags); 1802 xfs_trans_log_inode(tp, tip, target_log_flags); 1803 1804 /* 1805 * The extent forks have been swapped, but crc=1,rmapbt=0 filesystems 1806 * have inode number owner values in the bmbt blocks that still refer to 1807 * the old inode. Scan each bmbt to fix up the owner values with the 1808 * inode number of the current inode. 1809 */ 1810 if (src_log_flags & XFS_ILOG_DOWNER) { 1811 error = xfs_swap_change_owner(&tp, ip, tip); 1812 if (error) 1813 goto out_trans_cancel; 1814 } 1815 if (target_log_flags & XFS_ILOG_DOWNER) { 1816 error = xfs_swap_change_owner(&tp, tip, ip); 1817 if (error) 1818 goto out_trans_cancel; 1819 } 1820 1821 /* 1822 * If this is a synchronous mount, make sure that the 1823 * transaction goes to disk before returning to the user. 1824 */ 1825 if (mp->m_flags & XFS_MOUNT_WSYNC) 1826 xfs_trans_set_sync(tp); 1827 1828 error = xfs_trans_commit(tp); 1829 1830 trace_xfs_swap_extent_after(ip, 0); 1831 trace_xfs_swap_extent_after(tip, 1); 1832 1833 out_unlock: 1834 xfs_iunlock(ip, lock_flags); 1835 xfs_iunlock(tip, lock_flags); 1836 unlock_two_nondirectories(VFS_I(ip), VFS_I(tip)); 1837 return error; 1838 1839 out_trans_cancel: 1840 xfs_trans_cancel(tp); 1841 goto out_unlock; 1842 } 1843