1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright (c) 2000-2006 Silicon Graphics, Inc. 4 * All Rights Reserved. 5 */ 6 #include <linux/iversion.h> 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_sb.h" 14 #include "xfs_mount.h" 15 #include "xfs_inode.h" 16 #include "xfs_inode_util.h" 17 #include "xfs_trans.h" 18 #include "xfs_ialloc.h" 19 #include "xfs_health.h" 20 #include "xfs_bmap.h" 21 #include "xfs_error.h" 22 #include "xfs_trace.h" 23 #include "xfs_ag.h" 24 #include "xfs_iunlink_item.h" 25 #include "xfs_inode_item.h" 26 27 uint16_t 28 xfs_flags2diflags( 29 struct xfs_inode *ip, 30 unsigned int xflags) 31 { 32 /* can't set PREALLOC this way, just preserve it */ 33 uint16_t di_flags = 34 (ip->i_diflags & XFS_DIFLAG_PREALLOC); 35 36 if (xflags & FS_XFLAG_IMMUTABLE) 37 di_flags |= XFS_DIFLAG_IMMUTABLE; 38 if (xflags & FS_XFLAG_APPEND) 39 di_flags |= XFS_DIFLAG_APPEND; 40 if (xflags & FS_XFLAG_SYNC) 41 di_flags |= XFS_DIFLAG_SYNC; 42 if (xflags & FS_XFLAG_NOATIME) 43 di_flags |= XFS_DIFLAG_NOATIME; 44 if (xflags & FS_XFLAG_NODUMP) 45 di_flags |= XFS_DIFLAG_NODUMP; 46 if (xflags & FS_XFLAG_NODEFRAG) 47 di_flags |= XFS_DIFLAG_NODEFRAG; 48 if (xflags & FS_XFLAG_FILESTREAM) 49 di_flags |= XFS_DIFLAG_FILESTREAM; 50 if (S_ISDIR(VFS_I(ip)->i_mode)) { 51 if (xflags & FS_XFLAG_RTINHERIT) 52 di_flags |= XFS_DIFLAG_RTINHERIT; 53 if (xflags & FS_XFLAG_NOSYMLINKS) 54 di_flags |= XFS_DIFLAG_NOSYMLINKS; 55 if (xflags & FS_XFLAG_EXTSZINHERIT) 56 di_flags |= XFS_DIFLAG_EXTSZINHERIT; 57 if (xflags & FS_XFLAG_PROJINHERIT) 58 di_flags |= XFS_DIFLAG_PROJINHERIT; 59 } else if (S_ISREG(VFS_I(ip)->i_mode)) { 60 if (xflags & FS_XFLAG_REALTIME) 61 di_flags |= XFS_DIFLAG_REALTIME; 62 if (xflags & FS_XFLAG_EXTSIZE) 63 di_flags |= XFS_DIFLAG_EXTSIZE; 64 } 65 66 return di_flags; 67 } 68 69 uint64_t 70 xfs_flags2diflags2( 71 struct xfs_inode *ip, 72 unsigned int xflags) 73 { 74 uint64_t di_flags2 = 75 (ip->i_diflags2 & (XFS_DIFLAG2_REFLINK | 76 XFS_DIFLAG2_BIGTIME | 77 XFS_DIFLAG2_NREXT64)); 78 79 if (xflags & FS_XFLAG_DAX) 80 di_flags2 |= XFS_DIFLAG2_DAX; 81 if (xflags & FS_XFLAG_COWEXTSIZE) 82 di_flags2 |= XFS_DIFLAG2_COWEXTSIZE; 83 84 return di_flags2; 85 } 86 87 uint32_t 88 xfs_ip2xflags( 89 struct xfs_inode *ip) 90 { 91 uint32_t flags = 0; 92 93 if (ip->i_diflags & XFS_DIFLAG_ANY) { 94 if (ip->i_diflags & XFS_DIFLAG_REALTIME) 95 flags |= FS_XFLAG_REALTIME; 96 if (ip->i_diflags & XFS_DIFLAG_PREALLOC) 97 flags |= FS_XFLAG_PREALLOC; 98 if (ip->i_diflags & XFS_DIFLAG_IMMUTABLE) 99 flags |= FS_XFLAG_IMMUTABLE; 100 if (ip->i_diflags & XFS_DIFLAG_APPEND) 101 flags |= FS_XFLAG_APPEND; 102 if (ip->i_diflags & XFS_DIFLAG_SYNC) 103 flags |= FS_XFLAG_SYNC; 104 if (ip->i_diflags & XFS_DIFLAG_NOATIME) 105 flags |= FS_XFLAG_NOATIME; 106 if (ip->i_diflags & XFS_DIFLAG_NODUMP) 107 flags |= FS_XFLAG_NODUMP; 108 if (ip->i_diflags & XFS_DIFLAG_RTINHERIT) 109 flags |= FS_XFLAG_RTINHERIT; 110 if (ip->i_diflags & XFS_DIFLAG_PROJINHERIT) 111 flags |= FS_XFLAG_PROJINHERIT; 112 if (ip->i_diflags & XFS_DIFLAG_NOSYMLINKS) 113 flags |= FS_XFLAG_NOSYMLINKS; 114 if (ip->i_diflags & XFS_DIFLAG_EXTSIZE) 115 flags |= FS_XFLAG_EXTSIZE; 116 if (ip->i_diflags & XFS_DIFLAG_EXTSZINHERIT) 117 flags |= FS_XFLAG_EXTSZINHERIT; 118 if (ip->i_diflags & XFS_DIFLAG_NODEFRAG) 119 flags |= FS_XFLAG_NODEFRAG; 120 if (ip->i_diflags & XFS_DIFLAG_FILESTREAM) 121 flags |= FS_XFLAG_FILESTREAM; 122 } 123 124 if (ip->i_diflags2 & XFS_DIFLAG2_ANY) { 125 if (ip->i_diflags2 & XFS_DIFLAG2_DAX) 126 flags |= FS_XFLAG_DAX; 127 if (ip->i_diflags2 & XFS_DIFLAG2_COWEXTSIZE) 128 flags |= FS_XFLAG_COWEXTSIZE; 129 } 130 131 if (xfs_inode_has_attr_fork(ip)) 132 flags |= FS_XFLAG_HASATTR; 133 return flags; 134 } 135 136 prid_t 137 xfs_get_initial_prid(struct xfs_inode *dp) 138 { 139 if (dp->i_diflags & XFS_DIFLAG_PROJINHERIT) 140 return dp->i_projid; 141 142 /* Assign to the root project by default. */ 143 return 0; 144 } 145 146 /* Propagate di_flags from a parent inode to a child inode. */ 147 static inline void 148 xfs_inode_inherit_flags( 149 struct xfs_inode *ip, 150 const struct xfs_inode *pip) 151 { 152 unsigned int di_flags = 0; 153 xfs_failaddr_t failaddr; 154 umode_t mode = VFS_I(ip)->i_mode; 155 156 if (S_ISDIR(mode)) { 157 if (pip->i_diflags & XFS_DIFLAG_RTINHERIT) 158 di_flags |= XFS_DIFLAG_RTINHERIT; 159 if (pip->i_diflags & XFS_DIFLAG_EXTSZINHERIT) { 160 di_flags |= XFS_DIFLAG_EXTSZINHERIT; 161 ip->i_extsize = pip->i_extsize; 162 } 163 if (pip->i_diflags & XFS_DIFLAG_PROJINHERIT) 164 di_flags |= XFS_DIFLAG_PROJINHERIT; 165 } else if (S_ISREG(mode)) { 166 if ((pip->i_diflags & XFS_DIFLAG_RTINHERIT) && 167 xfs_has_realtime(ip->i_mount)) 168 di_flags |= XFS_DIFLAG_REALTIME; 169 if (pip->i_diflags & XFS_DIFLAG_EXTSZINHERIT) { 170 di_flags |= XFS_DIFLAG_EXTSIZE; 171 ip->i_extsize = pip->i_extsize; 172 } 173 } 174 if ((pip->i_diflags & XFS_DIFLAG_NOATIME) && 175 xfs_inherit_noatime) 176 di_flags |= XFS_DIFLAG_NOATIME; 177 if ((pip->i_diflags & XFS_DIFLAG_NODUMP) && 178 xfs_inherit_nodump) 179 di_flags |= XFS_DIFLAG_NODUMP; 180 if ((pip->i_diflags & XFS_DIFLAG_SYNC) && 181 xfs_inherit_sync) 182 di_flags |= XFS_DIFLAG_SYNC; 183 if ((pip->i_diflags & XFS_DIFLAG_NOSYMLINKS) && 184 xfs_inherit_nosymlinks) 185 di_flags |= XFS_DIFLAG_NOSYMLINKS; 186 if ((pip->i_diflags & XFS_DIFLAG_NODEFRAG) && 187 xfs_inherit_nodefrag) 188 di_flags |= XFS_DIFLAG_NODEFRAG; 189 if (pip->i_diflags & XFS_DIFLAG_FILESTREAM) 190 di_flags |= XFS_DIFLAG_FILESTREAM; 191 192 ip->i_diflags |= di_flags; 193 194 /* 195 * Inode verifiers on older kernels only check that the extent size 196 * hint is an integer multiple of the rt extent size on realtime files. 197 * They did not check the hint alignment on a directory with both 198 * rtinherit and extszinherit flags set. If the misaligned hint is 199 * propagated from a directory into a new realtime file, new file 200 * allocations will fail due to math errors in the rt allocator and/or 201 * trip the verifiers. Validate the hint settings in the new file so 202 * that we don't let broken hints propagate. 203 */ 204 failaddr = xfs_inode_validate_extsize(ip->i_mount, ip->i_extsize, 205 VFS_I(ip)->i_mode, ip->i_diflags); 206 if (failaddr) { 207 ip->i_diflags &= ~(XFS_DIFLAG_EXTSIZE | 208 XFS_DIFLAG_EXTSZINHERIT); 209 ip->i_extsize = 0; 210 } 211 } 212 213 /* Propagate di_flags2 from a parent inode to a child inode. */ 214 static inline void 215 xfs_inode_inherit_flags2( 216 struct xfs_inode *ip, 217 const struct xfs_inode *pip) 218 { 219 xfs_failaddr_t failaddr; 220 221 if (pip->i_diflags2 & XFS_DIFLAG2_COWEXTSIZE) { 222 ip->i_diflags2 |= XFS_DIFLAG2_COWEXTSIZE; 223 ip->i_cowextsize = pip->i_cowextsize; 224 } 225 if (pip->i_diflags2 & XFS_DIFLAG2_DAX) 226 ip->i_diflags2 |= XFS_DIFLAG2_DAX; 227 228 /* Don't let invalid cowextsize hints propagate. */ 229 failaddr = xfs_inode_validate_cowextsize(ip->i_mount, ip->i_cowextsize, 230 VFS_I(ip)->i_mode, ip->i_diflags, ip->i_diflags2); 231 if (failaddr) { 232 ip->i_diflags2 &= ~XFS_DIFLAG2_COWEXTSIZE; 233 ip->i_cowextsize = 0; 234 } 235 } 236 237 /* 238 * If we need to create attributes immediately after allocating the inode, 239 * initialise an empty attribute fork right now. We use the default fork offset 240 * for attributes here as we don't know exactly what size or how many 241 * attributes we might be adding. We can do this safely here because we know 242 * the data fork is completely empty and this saves us from needing to run a 243 * separate transaction to set the fork offset in the immediate future. 244 * 245 * If we have parent pointers and the caller hasn't told us that the file will 246 * never be linked into a directory tree, we /must/ create the attr fork. 247 */ 248 static inline bool 249 xfs_icreate_want_attrfork( 250 struct xfs_mount *mp, 251 const struct xfs_icreate_args *args) 252 { 253 if (args->flags & XFS_ICREATE_INIT_XATTRS) 254 return true; 255 256 if (!(args->flags & XFS_ICREATE_UNLINKABLE) && xfs_has_parent(mp)) 257 return true; 258 259 return false; 260 } 261 262 /* Initialise an inode's attributes. */ 263 void 264 xfs_inode_init( 265 struct xfs_trans *tp, 266 const struct xfs_icreate_args *args, 267 struct xfs_inode *ip) 268 { 269 struct xfs_inode *pip = args->pip; 270 struct inode *dir = pip ? VFS_I(pip) : NULL; 271 struct xfs_mount *mp = tp->t_mountp; 272 struct inode *inode = VFS_I(ip); 273 unsigned int flags; 274 int times = XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG | 275 XFS_ICHGTIME_ACCESS; 276 277 if (args->flags & XFS_ICREATE_TMPFILE) 278 set_nlink(inode, 0); 279 else if (S_ISDIR(args->mode)) 280 set_nlink(inode, 2); 281 else 282 set_nlink(inode, 1); 283 inode->i_rdev = args->rdev; 284 285 if (!args->idmap || pip == NULL) { 286 /* creating a tree root, sb rooted, or detached file */ 287 inode->i_uid = GLOBAL_ROOT_UID; 288 inode->i_gid = GLOBAL_ROOT_GID; 289 ip->i_projid = 0; 290 inode->i_mode = args->mode; 291 } else { 292 /* creating a child in the directory tree */ 293 if (dir && !(dir->i_mode & S_ISGID) && xfs_has_grpid(mp)) { 294 inode_fsuid_set(inode, args->idmap); 295 inode->i_gid = dir->i_gid; 296 inode->i_mode = args->mode; 297 } else { 298 inode_init_owner(args->idmap, inode, dir, args->mode); 299 } 300 301 /* 302 * If the group ID of the new file does not match the effective 303 * group ID or one of the supplementary group IDs, the S_ISGID 304 * bit is cleared (and only if the irix_sgid_inherit 305 * compatibility variable is set). 306 */ 307 if (irix_sgid_inherit && (inode->i_mode & S_ISGID) && 308 !vfsgid_in_group_p(i_gid_into_vfsgid(args->idmap, inode))) 309 inode->i_mode &= ~S_ISGID; 310 311 ip->i_projid = pip ? xfs_get_initial_prid(pip) : 0; 312 } 313 314 ip->i_disk_size = 0; 315 ip->i_df.if_nextents = 0; 316 ASSERT(ip->i_nblocks == 0); 317 318 ip->i_extsize = 0; 319 ip->i_diflags = 0; 320 321 if (xfs_has_v3inodes(mp)) { 322 inode_set_iversion(inode, 1); 323 ip->i_cowextsize = 0; 324 times |= XFS_ICHGTIME_CREATE; 325 } 326 327 xfs_trans_ichgtime(tp, ip, times); 328 329 flags = XFS_ILOG_CORE; 330 switch (args->mode & S_IFMT) { 331 case S_IFIFO: 332 case S_IFCHR: 333 case S_IFBLK: 334 case S_IFSOCK: 335 ip->i_df.if_format = XFS_DINODE_FMT_DEV; 336 flags |= XFS_ILOG_DEV; 337 break; 338 case S_IFREG: 339 case S_IFDIR: 340 if (pip && (pip->i_diflags & XFS_DIFLAG_ANY)) 341 xfs_inode_inherit_flags(ip, pip); 342 if (pip && (pip->i_diflags2 & XFS_DIFLAG2_ANY)) 343 xfs_inode_inherit_flags2(ip, pip); 344 fallthrough; 345 case S_IFLNK: 346 ip->i_df.if_format = XFS_DINODE_FMT_EXTENTS; 347 ip->i_df.if_bytes = 0; 348 ip->i_df.if_data = NULL; 349 break; 350 default: 351 ASSERT(0); 352 } 353 354 if (xfs_icreate_want_attrfork(mp, args)) { 355 ip->i_forkoff = xfs_default_attroffset(ip) >> 3; 356 xfs_ifork_init_attr(ip, XFS_DINODE_FMT_EXTENTS, 0); 357 358 if (!xfs_has_attr(mp)) { 359 spin_lock(&mp->m_sb_lock); 360 xfs_add_attr(mp); 361 spin_unlock(&mp->m_sb_lock); 362 xfs_log_sb(tp); 363 } 364 } 365 366 xfs_trans_log_inode(tp, ip, flags); 367 } 368 369 /* 370 * In-Core Unlinked List Lookups 371 * ============================= 372 * 373 * Every inode is supposed to be reachable from some other piece of metadata 374 * with the exception of the root directory. Inodes with a connection to a 375 * file descriptor but not linked from anywhere in the on-disk directory tree 376 * are collectively known as unlinked inodes, though the filesystem itself 377 * maintains links to these inodes so that on-disk metadata are consistent. 378 * 379 * XFS implements a per-AG on-disk hash table of unlinked inodes. The AGI 380 * header contains a number of buckets that point to an inode, and each inode 381 * record has a pointer to the next inode in the hash chain. This 382 * singly-linked list causes scaling problems in the iunlink remove function 383 * because we must walk that list to find the inode that points to the inode 384 * being removed from the unlinked hash bucket list. 385 * 386 * Hence we keep an in-memory double linked list to link each inode on an 387 * unlinked list. Because there are 64 unlinked lists per AGI, keeping pointer 388 * based lists would require having 64 list heads in the perag, one for each 389 * list. This is expensive in terms of memory (think millions of AGs) and cache 390 * misses on lookups. Instead, use the fact that inodes on the unlinked list 391 * must be referenced at the VFS level to keep them on the list and hence we 392 * have an existence guarantee for inodes on the unlinked list. 393 * 394 * Given we have an existence guarantee, we can use lockless inode cache lookups 395 * to resolve aginos to xfs inodes. This means we only need 8 bytes per inode 396 * for the double linked unlinked list, and we don't need any extra locking to 397 * keep the list safe as all manipulations are done under the AGI buffer lock. 398 * Keeping the list up to date does not require memory allocation, just finding 399 * the XFS inode and updating the next/prev unlinked list aginos. 400 */ 401 402 /* 403 * Update the prev pointer of the next agino. Returns -ENOLINK if the inode 404 * is not in cache. 405 */ 406 static int 407 xfs_iunlink_update_backref( 408 struct xfs_perag *pag, 409 xfs_agino_t prev_agino, 410 xfs_agino_t next_agino) 411 { 412 struct xfs_inode *ip; 413 414 /* No update necessary if we are at the end of the list. */ 415 if (next_agino == NULLAGINO) 416 return 0; 417 418 ip = xfs_iunlink_lookup(pag, next_agino); 419 if (!ip) 420 return -ENOLINK; 421 422 ip->i_prev_unlinked = prev_agino; 423 return 0; 424 } 425 426 /* 427 * Point the AGI unlinked bucket at an inode and log the results. The caller 428 * is responsible for validating the old value. 429 */ 430 STATIC int 431 xfs_iunlink_update_bucket( 432 struct xfs_trans *tp, 433 struct xfs_perag *pag, 434 struct xfs_buf *agibp, 435 unsigned int bucket_index, 436 xfs_agino_t new_agino) 437 { 438 struct xfs_agi *agi = agibp->b_addr; 439 xfs_agino_t old_value; 440 int offset; 441 442 ASSERT(xfs_verify_agino_or_null(pag, new_agino)); 443 444 old_value = be32_to_cpu(agi->agi_unlinked[bucket_index]); 445 trace_xfs_iunlink_update_bucket(tp->t_mountp, pag->pag_agno, bucket_index, 446 old_value, new_agino); 447 448 /* 449 * We should never find the head of the list already set to the value 450 * passed in because either we're adding or removing ourselves from the 451 * head of the list. 452 */ 453 if (old_value == new_agino) { 454 xfs_buf_mark_corrupt(agibp); 455 xfs_ag_mark_sick(pag, XFS_SICK_AG_AGI); 456 return -EFSCORRUPTED; 457 } 458 459 agi->agi_unlinked[bucket_index] = cpu_to_be32(new_agino); 460 offset = offsetof(struct xfs_agi, agi_unlinked) + 461 (sizeof(xfs_agino_t) * bucket_index); 462 xfs_trans_log_buf(tp, agibp, offset, offset + sizeof(xfs_agino_t) - 1); 463 return 0; 464 } 465 466 static int 467 xfs_iunlink_insert_inode( 468 struct xfs_trans *tp, 469 struct xfs_perag *pag, 470 struct xfs_buf *agibp, 471 struct xfs_inode *ip) 472 { 473 struct xfs_mount *mp = tp->t_mountp; 474 struct xfs_agi *agi = agibp->b_addr; 475 xfs_agino_t next_agino; 476 xfs_agino_t agino = XFS_INO_TO_AGINO(mp, ip->i_ino); 477 short bucket_index = agino % XFS_AGI_UNLINKED_BUCKETS; 478 int error; 479 480 /* 481 * Get the index into the agi hash table for the list this inode will 482 * go on. Make sure the pointer isn't garbage and that this inode 483 * isn't already on the list. 484 */ 485 next_agino = be32_to_cpu(agi->agi_unlinked[bucket_index]); 486 if (next_agino == agino || 487 !xfs_verify_agino_or_null(pag, next_agino)) { 488 xfs_buf_mark_corrupt(agibp); 489 xfs_ag_mark_sick(pag, XFS_SICK_AG_AGI); 490 return -EFSCORRUPTED; 491 } 492 493 /* 494 * Update the prev pointer in the next inode to point back to this 495 * inode. 496 */ 497 error = xfs_iunlink_update_backref(pag, agino, next_agino); 498 if (error == -ENOLINK) 499 error = xfs_iunlink_reload_next(tp, agibp, agino, next_agino); 500 if (error) 501 return error; 502 503 if (next_agino != NULLAGINO) { 504 /* 505 * There is already another inode in the bucket, so point this 506 * inode to the current head of the list. 507 */ 508 error = xfs_iunlink_log_inode(tp, ip, pag, next_agino); 509 if (error) 510 return error; 511 ip->i_next_unlinked = next_agino; 512 } 513 514 /* Point the head of the list to point to this inode. */ 515 ip->i_prev_unlinked = NULLAGINO; 516 return xfs_iunlink_update_bucket(tp, pag, agibp, bucket_index, agino); 517 } 518 519 /* 520 * This is called when the inode's link count has gone to 0 or we are creating 521 * a tmpfile via O_TMPFILE. The inode @ip must have nlink == 0. 522 * 523 * We place the on-disk inode on a list in the AGI. It will be pulled from this 524 * list when the inode is freed. 525 */ 526 int 527 xfs_iunlink( 528 struct xfs_trans *tp, 529 struct xfs_inode *ip) 530 { 531 struct xfs_mount *mp = tp->t_mountp; 532 struct xfs_perag *pag; 533 struct xfs_buf *agibp; 534 int error; 535 536 ASSERT(VFS_I(ip)->i_nlink == 0); 537 ASSERT(VFS_I(ip)->i_mode != 0); 538 trace_xfs_iunlink(ip); 539 540 pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, ip->i_ino)); 541 542 /* Get the agi buffer first. It ensures lock ordering on the list. */ 543 error = xfs_read_agi(pag, tp, 0, &agibp); 544 if (error) 545 goto out; 546 547 error = xfs_iunlink_insert_inode(tp, pag, agibp, ip); 548 out: 549 xfs_perag_put(pag); 550 return error; 551 } 552 553 static int 554 xfs_iunlink_remove_inode( 555 struct xfs_trans *tp, 556 struct xfs_perag *pag, 557 struct xfs_buf *agibp, 558 struct xfs_inode *ip) 559 { 560 struct xfs_mount *mp = tp->t_mountp; 561 struct xfs_agi *agi = agibp->b_addr; 562 xfs_agino_t agino = XFS_INO_TO_AGINO(mp, ip->i_ino); 563 xfs_agino_t head_agino; 564 short bucket_index = agino % XFS_AGI_UNLINKED_BUCKETS; 565 int error; 566 567 trace_xfs_iunlink_remove(ip); 568 569 /* 570 * Get the index into the agi hash table for the list this inode will 571 * go on. Make sure the head pointer isn't garbage. 572 */ 573 head_agino = be32_to_cpu(agi->agi_unlinked[bucket_index]); 574 if (!xfs_verify_agino(pag, head_agino)) { 575 XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, 576 agi, sizeof(*agi)); 577 xfs_ag_mark_sick(pag, XFS_SICK_AG_AGI); 578 return -EFSCORRUPTED; 579 } 580 581 /* 582 * Set our inode's next_unlinked pointer to NULL and then return 583 * the old pointer value so that we can update whatever was previous 584 * to us in the list to point to whatever was next in the list. 585 */ 586 error = xfs_iunlink_log_inode(tp, ip, pag, NULLAGINO); 587 if (error) 588 return error; 589 590 /* 591 * Update the prev pointer in the next inode to point back to previous 592 * inode in the chain. 593 */ 594 error = xfs_iunlink_update_backref(pag, ip->i_prev_unlinked, 595 ip->i_next_unlinked); 596 if (error == -ENOLINK) 597 error = xfs_iunlink_reload_next(tp, agibp, ip->i_prev_unlinked, 598 ip->i_next_unlinked); 599 if (error) 600 return error; 601 602 if (head_agino != agino) { 603 struct xfs_inode *prev_ip; 604 605 prev_ip = xfs_iunlink_lookup(pag, ip->i_prev_unlinked); 606 if (!prev_ip) { 607 xfs_inode_mark_sick(ip, XFS_SICK_INO_CORE); 608 return -EFSCORRUPTED; 609 } 610 611 error = xfs_iunlink_log_inode(tp, prev_ip, pag, 612 ip->i_next_unlinked); 613 prev_ip->i_next_unlinked = ip->i_next_unlinked; 614 } else { 615 /* Point the head of the list to the next unlinked inode. */ 616 error = xfs_iunlink_update_bucket(tp, pag, agibp, bucket_index, 617 ip->i_next_unlinked); 618 } 619 620 ip->i_next_unlinked = NULLAGINO; 621 ip->i_prev_unlinked = 0; 622 return error; 623 } 624 625 /* 626 * Pull the on-disk inode from the AGI unlinked list. 627 */ 628 int 629 xfs_iunlink_remove( 630 struct xfs_trans *tp, 631 struct xfs_perag *pag, 632 struct xfs_inode *ip) 633 { 634 struct xfs_buf *agibp; 635 int error; 636 637 trace_xfs_iunlink_remove(ip); 638 639 /* Get the agi buffer first. It ensures lock ordering on the list. */ 640 error = xfs_read_agi(pag, tp, 0, &agibp); 641 if (error) 642 return error; 643 644 return xfs_iunlink_remove_inode(tp, pag, agibp, ip); 645 } 646 647 /* 648 * Decrement the link count on an inode & log the change. If this causes the 649 * link count to go to zero, move the inode to AGI unlinked list so that it can 650 * be freed when the last active reference goes away via xfs_inactive(). 651 */ 652 int 653 xfs_droplink( 654 struct xfs_trans *tp, 655 struct xfs_inode *ip) 656 { 657 struct inode *inode = VFS_I(ip); 658 659 xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_CHG); 660 661 if (inode->i_nlink == 0) { 662 xfs_info_ratelimited(tp->t_mountp, 663 "Inode 0x%llx link count dropped below zero. Pinning link count.", 664 ip->i_ino); 665 set_nlink(inode, XFS_NLINK_PINNED); 666 } 667 if (inode->i_nlink != XFS_NLINK_PINNED) 668 drop_nlink(inode); 669 670 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE); 671 672 if (inode->i_nlink) 673 return 0; 674 675 return xfs_iunlink(tp, ip); 676 } 677 678 /* 679 * Increment the link count on an inode & log the change. 680 */ 681 void 682 xfs_bumplink( 683 struct xfs_trans *tp, 684 struct xfs_inode *ip) 685 { 686 struct inode *inode = VFS_I(ip); 687 688 xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_CHG); 689 690 if (inode->i_nlink == XFS_NLINK_PINNED - 1) 691 xfs_info_ratelimited(tp->t_mountp, 692 "Inode 0x%llx link count exceeded maximum. Pinning link count.", 693 ip->i_ino); 694 if (inode->i_nlink != XFS_NLINK_PINNED) 695 inc_nlink(inode); 696 697 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE); 698 } 699 700 /* Free an inode in the ondisk index and zero it out. */ 701 int 702 xfs_inode_uninit( 703 struct xfs_trans *tp, 704 struct xfs_perag *pag, 705 struct xfs_inode *ip, 706 struct xfs_icluster *xic) 707 { 708 struct xfs_mount *mp = ip->i_mount; 709 int error; 710 711 /* 712 * Free the inode first so that we guarantee that the AGI lock is going 713 * to be taken before we remove the inode from the unlinked list. This 714 * makes the AGI lock -> unlinked list modification order the same as 715 * used in O_TMPFILE creation. 716 */ 717 error = xfs_difree(tp, pag, ip->i_ino, xic); 718 if (error) 719 return error; 720 721 error = xfs_iunlink_remove(tp, pag, ip); 722 if (error) 723 return error; 724 725 /* 726 * Free any local-format data sitting around before we reset the 727 * data fork to extents format. Note that the attr fork data has 728 * already been freed by xfs_attr_inactive. 729 */ 730 if (ip->i_df.if_format == XFS_DINODE_FMT_LOCAL) { 731 kfree(ip->i_df.if_data); 732 ip->i_df.if_data = NULL; 733 ip->i_df.if_bytes = 0; 734 } 735 736 VFS_I(ip)->i_mode = 0; /* mark incore inode as free */ 737 ip->i_diflags = 0; 738 ip->i_diflags2 = mp->m_ino_geo.new_diflags2; 739 ip->i_forkoff = 0; /* mark the attr fork not in use */ 740 ip->i_df.if_format = XFS_DINODE_FMT_EXTENTS; 741 742 /* 743 * Bump the generation count so no one will be confused 744 * by reincarnations of this inode. 745 */ 746 VFS_I(ip)->i_generation++; 747 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE); 748 return 0; 749 } 750