1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright (c) 2000-2005 Silicon Graphics, Inc. 4 * All Rights Reserved. 5 */ 6 #include "xfs.h" 7 #include "xfs_fs.h" 8 #include "xfs_shared.h" 9 #include "xfs_format.h" 10 #include "xfs_log_format.h" 11 #include "xfs_trans_resv.h" 12 #include "xfs_mount.h" 13 #include "xfs_inode.h" 14 #include "xfs_acl.h" 15 #include "xfs_quota.h" 16 #include "xfs_da_format.h" 17 #include "xfs_da_btree.h" 18 #include "xfs_attr.h" 19 #include "xfs_trans.h" 20 #include "xfs_trace.h" 21 #include "xfs_icache.h" 22 #include "xfs_symlink.h" 23 #include "xfs_dir2.h" 24 #include "xfs_iomap.h" 25 #include "xfs_error.h" 26 #include "xfs_ioctl.h" 27 #include "xfs_xattr.h" 28 29 #include <linux/posix_acl.h> 30 #include <linux/security.h> 31 #include <linux/iversion.h> 32 #include <linux/fiemap.h> 33 34 /* 35 * Directories have different lock order w.r.t. mmap_lock compared to regular 36 * files. This is due to readdir potentially triggering page faults on a user 37 * buffer inside filldir(), and this happens with the ilock on the directory 38 * held. For regular files, the lock order is the other way around - the 39 * mmap_lock is taken during the page fault, and then we lock the ilock to do 40 * block mapping. Hence we need a different class for the directory ilock so 41 * that lockdep can tell them apart. 42 */ 43 static struct lock_class_key xfs_nondir_ilock_class; 44 static struct lock_class_key xfs_dir_ilock_class; 45 46 static int 47 xfs_initxattrs( 48 struct inode *inode, 49 const struct xattr *xattr_array, 50 void *fs_info) 51 { 52 const struct xattr *xattr; 53 struct xfs_inode *ip = XFS_I(inode); 54 int error = 0; 55 56 for (xattr = xattr_array; xattr->name != NULL; xattr++) { 57 struct xfs_da_args args = { 58 .dp = ip, 59 .attr_filter = XFS_ATTR_SECURE, 60 .name = xattr->name, 61 .namelen = strlen(xattr->name), 62 .value = xattr->value, 63 .valuelen = xattr->value_len, 64 }; 65 error = xfs_attr_change(&args); 66 if (error < 0) 67 break; 68 } 69 return error; 70 } 71 72 /* 73 * Hook in SELinux. This is not quite correct yet, what we really need 74 * here (as we do for default ACLs) is a mechanism by which creation of 75 * these attrs can be journalled at inode creation time (along with the 76 * inode, of course, such that log replay can't cause these to be lost). 77 */ 78 int 79 xfs_inode_init_security( 80 struct inode *inode, 81 struct inode *dir, 82 const struct qstr *qstr) 83 { 84 return security_inode_init_security(inode, dir, qstr, 85 &xfs_initxattrs, NULL); 86 } 87 88 static void 89 xfs_dentry_to_name( 90 struct xfs_name *namep, 91 struct dentry *dentry) 92 { 93 namep->name = dentry->d_name.name; 94 namep->len = dentry->d_name.len; 95 namep->type = XFS_DIR3_FT_UNKNOWN; 96 } 97 98 static int 99 xfs_dentry_mode_to_name( 100 struct xfs_name *namep, 101 struct dentry *dentry, 102 int mode) 103 { 104 namep->name = dentry->d_name.name; 105 namep->len = dentry->d_name.len; 106 namep->type = xfs_mode_to_ftype(mode); 107 108 if (unlikely(namep->type == XFS_DIR3_FT_UNKNOWN)) 109 return -EFSCORRUPTED; 110 111 return 0; 112 } 113 114 STATIC void 115 xfs_cleanup_inode( 116 struct inode *dir, 117 struct inode *inode, 118 struct dentry *dentry) 119 { 120 struct xfs_name teardown; 121 122 /* Oh, the horror. 123 * If we can't add the ACL or we fail in 124 * xfs_inode_init_security we must back out. 125 * ENOSPC can hit here, among other things. 126 */ 127 xfs_dentry_to_name(&teardown, dentry); 128 129 xfs_remove(XFS_I(dir), &teardown, XFS_I(inode)); 130 } 131 132 /* 133 * Check to see if we are likely to need an extended attribute to be added to 134 * the inode we are about to allocate. This allows the attribute fork to be 135 * created during the inode allocation, reducing the number of transactions we 136 * need to do in this fast path. 137 * 138 * The security checks are optimistic, but not guaranteed. The two LSMs that 139 * require xattrs to be added here (selinux and smack) are also the only two 140 * LSMs that add a sb->s_security structure to the superblock. Hence if security 141 * is enabled and sb->s_security is set, we have a pretty good idea that we are 142 * going to be asked to add a security xattr immediately after allocating the 143 * xfs inode and instantiating the VFS inode. 144 */ 145 static inline bool 146 xfs_create_need_xattr( 147 struct inode *dir, 148 struct posix_acl *default_acl, 149 struct posix_acl *acl) 150 { 151 if (acl) 152 return true; 153 if (default_acl) 154 return true; 155 #if IS_ENABLED(CONFIG_SECURITY) 156 if (dir->i_sb->s_security) 157 return true; 158 #endif 159 return false; 160 } 161 162 163 STATIC int 164 xfs_generic_create( 165 struct user_namespace *mnt_userns, 166 struct inode *dir, 167 struct dentry *dentry, 168 umode_t mode, 169 dev_t rdev, 170 struct file *tmpfile) /* unnamed file */ 171 { 172 struct inode *inode; 173 struct xfs_inode *ip = NULL; 174 struct posix_acl *default_acl, *acl; 175 struct xfs_name name; 176 int error; 177 178 /* 179 * Irix uses Missed'em'V split, but doesn't want to see 180 * the upper 5 bits of (14bit) major. 181 */ 182 if (S_ISCHR(mode) || S_ISBLK(mode)) { 183 if (unlikely(!sysv_valid_dev(rdev) || MAJOR(rdev) & ~0x1ff)) 184 return -EINVAL; 185 } else { 186 rdev = 0; 187 } 188 189 error = posix_acl_create(dir, &mode, &default_acl, &acl); 190 if (error) 191 return error; 192 193 /* Verify mode is valid also for tmpfile case */ 194 error = xfs_dentry_mode_to_name(&name, dentry, mode); 195 if (unlikely(error)) 196 goto out_free_acl; 197 198 if (!tmpfile) { 199 error = xfs_create(mnt_userns, XFS_I(dir), &name, mode, rdev, 200 xfs_create_need_xattr(dir, default_acl, acl), 201 &ip); 202 } else { 203 error = xfs_create_tmpfile(mnt_userns, XFS_I(dir), mode, &ip); 204 } 205 if (unlikely(error)) 206 goto out_free_acl; 207 208 inode = VFS_I(ip); 209 210 error = xfs_inode_init_security(inode, dir, &dentry->d_name); 211 if (unlikely(error)) 212 goto out_cleanup_inode; 213 214 if (default_acl) { 215 error = __xfs_set_acl(inode, default_acl, ACL_TYPE_DEFAULT); 216 if (error) 217 goto out_cleanup_inode; 218 } 219 if (acl) { 220 error = __xfs_set_acl(inode, acl, ACL_TYPE_ACCESS); 221 if (error) 222 goto out_cleanup_inode; 223 } 224 225 xfs_setup_iops(ip); 226 227 if (tmpfile) { 228 /* 229 * The VFS requires that any inode fed to d_tmpfile must have 230 * nlink == 1 so that it can decrement the nlink in d_tmpfile. 231 * However, we created the temp file with nlink == 0 because 232 * we're not allowed to put an inode with nlink > 0 on the 233 * unlinked list. Therefore we have to set nlink to 1 so that 234 * d_tmpfile can immediately set it back to zero. 235 */ 236 set_nlink(inode, 1); 237 d_tmpfile(tmpfile, inode); 238 } else 239 d_instantiate(dentry, inode); 240 241 xfs_finish_inode_setup(ip); 242 243 out_free_acl: 244 posix_acl_release(default_acl); 245 posix_acl_release(acl); 246 return error; 247 248 out_cleanup_inode: 249 xfs_finish_inode_setup(ip); 250 if (!tmpfile) 251 xfs_cleanup_inode(dir, inode, dentry); 252 xfs_irele(ip); 253 goto out_free_acl; 254 } 255 256 STATIC int 257 xfs_vn_mknod( 258 struct user_namespace *mnt_userns, 259 struct inode *dir, 260 struct dentry *dentry, 261 umode_t mode, 262 dev_t rdev) 263 { 264 return xfs_generic_create(mnt_userns, dir, dentry, mode, rdev, NULL); 265 } 266 267 STATIC int 268 xfs_vn_create( 269 struct user_namespace *mnt_userns, 270 struct inode *dir, 271 struct dentry *dentry, 272 umode_t mode, 273 bool flags) 274 { 275 return xfs_generic_create(mnt_userns, dir, dentry, mode, 0, NULL); 276 } 277 278 STATIC int 279 xfs_vn_mkdir( 280 struct user_namespace *mnt_userns, 281 struct inode *dir, 282 struct dentry *dentry, 283 umode_t mode) 284 { 285 return xfs_generic_create(mnt_userns, dir, dentry, mode | S_IFDIR, 0, 286 NULL); 287 } 288 289 STATIC struct dentry * 290 xfs_vn_lookup( 291 struct inode *dir, 292 struct dentry *dentry, 293 unsigned int flags) 294 { 295 struct inode *inode; 296 struct xfs_inode *cip; 297 struct xfs_name name; 298 int error; 299 300 if (dentry->d_name.len >= MAXNAMELEN) 301 return ERR_PTR(-ENAMETOOLONG); 302 303 xfs_dentry_to_name(&name, dentry); 304 error = xfs_lookup(XFS_I(dir), &name, &cip, NULL); 305 if (likely(!error)) 306 inode = VFS_I(cip); 307 else if (likely(error == -ENOENT)) 308 inode = NULL; 309 else 310 inode = ERR_PTR(error); 311 return d_splice_alias(inode, dentry); 312 } 313 314 STATIC struct dentry * 315 xfs_vn_ci_lookup( 316 struct inode *dir, 317 struct dentry *dentry, 318 unsigned int flags) 319 { 320 struct xfs_inode *ip; 321 struct xfs_name xname; 322 struct xfs_name ci_name; 323 struct qstr dname; 324 int error; 325 326 if (dentry->d_name.len >= MAXNAMELEN) 327 return ERR_PTR(-ENAMETOOLONG); 328 329 xfs_dentry_to_name(&xname, dentry); 330 error = xfs_lookup(XFS_I(dir), &xname, &ip, &ci_name); 331 if (unlikely(error)) { 332 if (unlikely(error != -ENOENT)) 333 return ERR_PTR(error); 334 /* 335 * call d_add(dentry, NULL) here when d_drop_negative_children 336 * is called in xfs_vn_mknod (ie. allow negative dentries 337 * with CI filesystems). 338 */ 339 return NULL; 340 } 341 342 /* if exact match, just splice and exit */ 343 if (!ci_name.name) 344 return d_splice_alias(VFS_I(ip), dentry); 345 346 /* else case-insensitive match... */ 347 dname.name = ci_name.name; 348 dname.len = ci_name.len; 349 dentry = d_add_ci(dentry, VFS_I(ip), &dname); 350 kmem_free(ci_name.name); 351 return dentry; 352 } 353 354 STATIC int 355 xfs_vn_link( 356 struct dentry *old_dentry, 357 struct inode *dir, 358 struct dentry *dentry) 359 { 360 struct inode *inode = d_inode(old_dentry); 361 struct xfs_name name; 362 int error; 363 364 error = xfs_dentry_mode_to_name(&name, dentry, inode->i_mode); 365 if (unlikely(error)) 366 return error; 367 368 error = xfs_link(XFS_I(dir), XFS_I(inode), &name); 369 if (unlikely(error)) 370 return error; 371 372 ihold(inode); 373 d_instantiate(dentry, inode); 374 return 0; 375 } 376 377 STATIC int 378 xfs_vn_unlink( 379 struct inode *dir, 380 struct dentry *dentry) 381 { 382 struct xfs_name name; 383 int error; 384 385 xfs_dentry_to_name(&name, dentry); 386 387 error = xfs_remove(XFS_I(dir), &name, XFS_I(d_inode(dentry))); 388 if (error) 389 return error; 390 391 /* 392 * With unlink, the VFS makes the dentry "negative": no inode, 393 * but still hashed. This is incompatible with case-insensitive 394 * mode, so invalidate (unhash) the dentry in CI-mode. 395 */ 396 if (xfs_has_asciici(XFS_M(dir->i_sb))) 397 d_invalidate(dentry); 398 return 0; 399 } 400 401 STATIC int 402 xfs_vn_symlink( 403 struct user_namespace *mnt_userns, 404 struct inode *dir, 405 struct dentry *dentry, 406 const char *symname) 407 { 408 struct inode *inode; 409 struct xfs_inode *cip = NULL; 410 struct xfs_name name; 411 int error; 412 umode_t mode; 413 414 mode = S_IFLNK | 415 (irix_symlink_mode ? 0777 & ~current_umask() : S_IRWXUGO); 416 error = xfs_dentry_mode_to_name(&name, dentry, mode); 417 if (unlikely(error)) 418 goto out; 419 420 error = xfs_symlink(mnt_userns, XFS_I(dir), &name, symname, mode, &cip); 421 if (unlikely(error)) 422 goto out; 423 424 inode = VFS_I(cip); 425 426 error = xfs_inode_init_security(inode, dir, &dentry->d_name); 427 if (unlikely(error)) 428 goto out_cleanup_inode; 429 430 xfs_setup_iops(cip); 431 432 d_instantiate(dentry, inode); 433 xfs_finish_inode_setup(cip); 434 return 0; 435 436 out_cleanup_inode: 437 xfs_finish_inode_setup(cip); 438 xfs_cleanup_inode(dir, inode, dentry); 439 xfs_irele(cip); 440 out: 441 return error; 442 } 443 444 STATIC int 445 xfs_vn_rename( 446 struct user_namespace *mnt_userns, 447 struct inode *odir, 448 struct dentry *odentry, 449 struct inode *ndir, 450 struct dentry *ndentry, 451 unsigned int flags) 452 { 453 struct inode *new_inode = d_inode(ndentry); 454 int omode = 0; 455 int error; 456 struct xfs_name oname; 457 struct xfs_name nname; 458 459 if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE | RENAME_WHITEOUT)) 460 return -EINVAL; 461 462 /* if we are exchanging files, we need to set i_mode of both files */ 463 if (flags & RENAME_EXCHANGE) 464 omode = d_inode(ndentry)->i_mode; 465 466 error = xfs_dentry_mode_to_name(&oname, odentry, omode); 467 if (omode && unlikely(error)) 468 return error; 469 470 error = xfs_dentry_mode_to_name(&nname, ndentry, 471 d_inode(odentry)->i_mode); 472 if (unlikely(error)) 473 return error; 474 475 return xfs_rename(mnt_userns, XFS_I(odir), &oname, 476 XFS_I(d_inode(odentry)), XFS_I(ndir), &nname, 477 new_inode ? XFS_I(new_inode) : NULL, flags); 478 } 479 480 /* 481 * careful here - this function can get called recursively, so 482 * we need to be very careful about how much stack we use. 483 * uio is kmalloced for this reason... 484 */ 485 STATIC const char * 486 xfs_vn_get_link( 487 struct dentry *dentry, 488 struct inode *inode, 489 struct delayed_call *done) 490 { 491 char *link; 492 int error = -ENOMEM; 493 494 if (!dentry) 495 return ERR_PTR(-ECHILD); 496 497 link = kmalloc(XFS_SYMLINK_MAXLEN+1, GFP_KERNEL); 498 if (!link) 499 goto out_err; 500 501 error = xfs_readlink(XFS_I(d_inode(dentry)), link); 502 if (unlikely(error)) 503 goto out_kfree; 504 505 set_delayed_call(done, kfree_link, link); 506 return link; 507 508 out_kfree: 509 kfree(link); 510 out_err: 511 return ERR_PTR(error); 512 } 513 514 static uint32_t 515 xfs_stat_blksize( 516 struct xfs_inode *ip) 517 { 518 struct xfs_mount *mp = ip->i_mount; 519 520 /* 521 * If the file blocks are being allocated from a realtime volume, then 522 * always return the realtime extent size. 523 */ 524 if (XFS_IS_REALTIME_INODE(ip)) 525 return XFS_FSB_TO_B(mp, xfs_get_extsz_hint(ip)); 526 527 /* 528 * Allow large block sizes to be reported to userspace programs if the 529 * "largeio" mount option is used. 530 * 531 * If compatibility mode is specified, simply return the basic unit of 532 * caching so that we don't get inefficient read/modify/write I/O from 533 * user apps. Otherwise.... 534 * 535 * If the underlying volume is a stripe, then return the stripe width in 536 * bytes as the recommended I/O size. It is not a stripe and we've set a 537 * default buffered I/O size, return that, otherwise return the compat 538 * default. 539 */ 540 if (xfs_has_large_iosize(mp)) { 541 if (mp->m_swidth) 542 return XFS_FSB_TO_B(mp, mp->m_swidth); 543 if (xfs_has_allocsize(mp)) 544 return 1U << mp->m_allocsize_log; 545 } 546 547 return PAGE_SIZE; 548 } 549 550 STATIC int 551 xfs_vn_getattr( 552 struct user_namespace *mnt_userns, 553 const struct path *path, 554 struct kstat *stat, 555 u32 request_mask, 556 unsigned int query_flags) 557 { 558 struct inode *inode = d_inode(path->dentry); 559 struct xfs_inode *ip = XFS_I(inode); 560 struct xfs_mount *mp = ip->i_mount; 561 vfsuid_t vfsuid = i_uid_into_vfsuid(mnt_userns, inode); 562 vfsgid_t vfsgid = i_gid_into_vfsgid(mnt_userns, inode); 563 564 trace_xfs_getattr(ip); 565 566 if (xfs_is_shutdown(mp)) 567 return -EIO; 568 569 stat->size = XFS_ISIZE(ip); 570 stat->dev = inode->i_sb->s_dev; 571 stat->mode = inode->i_mode; 572 stat->nlink = inode->i_nlink; 573 stat->uid = vfsuid_into_kuid(vfsuid); 574 stat->gid = vfsgid_into_kgid(vfsgid); 575 stat->ino = ip->i_ino; 576 stat->atime = inode->i_atime; 577 stat->mtime = inode->i_mtime; 578 stat->ctime = inode->i_ctime; 579 stat->blocks = XFS_FSB_TO_BB(mp, ip->i_nblocks + ip->i_delayed_blks); 580 581 if (xfs_has_v3inodes(mp)) { 582 if (request_mask & STATX_BTIME) { 583 stat->result_mask |= STATX_BTIME; 584 stat->btime = ip->i_crtime; 585 } 586 } 587 588 /* 589 * Note: If you add another clause to set an attribute flag, please 590 * update attributes_mask below. 591 */ 592 if (ip->i_diflags & XFS_DIFLAG_IMMUTABLE) 593 stat->attributes |= STATX_ATTR_IMMUTABLE; 594 if (ip->i_diflags & XFS_DIFLAG_APPEND) 595 stat->attributes |= STATX_ATTR_APPEND; 596 if (ip->i_diflags & XFS_DIFLAG_NODUMP) 597 stat->attributes |= STATX_ATTR_NODUMP; 598 599 stat->attributes_mask |= (STATX_ATTR_IMMUTABLE | 600 STATX_ATTR_APPEND | 601 STATX_ATTR_NODUMP); 602 603 switch (inode->i_mode & S_IFMT) { 604 case S_IFBLK: 605 case S_IFCHR: 606 stat->blksize = BLKDEV_IOSIZE; 607 stat->rdev = inode->i_rdev; 608 break; 609 case S_IFREG: 610 if (request_mask & STATX_DIOALIGN) { 611 struct xfs_buftarg *target = xfs_inode_buftarg(ip); 612 struct block_device *bdev = target->bt_bdev; 613 614 stat->result_mask |= STATX_DIOALIGN; 615 stat->dio_mem_align = bdev_dma_alignment(bdev) + 1; 616 stat->dio_offset_align = bdev_logical_block_size(bdev); 617 } 618 fallthrough; 619 default: 620 stat->blksize = xfs_stat_blksize(ip); 621 stat->rdev = 0; 622 break; 623 } 624 625 return 0; 626 } 627 628 static int 629 xfs_vn_change_ok( 630 struct user_namespace *mnt_userns, 631 struct dentry *dentry, 632 struct iattr *iattr) 633 { 634 struct xfs_mount *mp = XFS_I(d_inode(dentry))->i_mount; 635 636 if (xfs_is_readonly(mp)) 637 return -EROFS; 638 639 if (xfs_is_shutdown(mp)) 640 return -EIO; 641 642 return setattr_prepare(mnt_userns, dentry, iattr); 643 } 644 645 /* 646 * Set non-size attributes of an inode. 647 * 648 * Caution: The caller of this function is responsible for calling 649 * setattr_prepare() or otherwise verifying the change is fine. 650 */ 651 static int 652 xfs_setattr_nonsize( 653 struct user_namespace *mnt_userns, 654 struct xfs_inode *ip, 655 struct iattr *iattr) 656 { 657 xfs_mount_t *mp = ip->i_mount; 658 struct inode *inode = VFS_I(ip); 659 int mask = iattr->ia_valid; 660 xfs_trans_t *tp; 661 int error; 662 kuid_t uid = GLOBAL_ROOT_UID; 663 kgid_t gid = GLOBAL_ROOT_GID; 664 struct xfs_dquot *udqp = NULL, *gdqp = NULL; 665 struct xfs_dquot *old_udqp = NULL, *old_gdqp = NULL; 666 667 ASSERT((mask & ATTR_SIZE) == 0); 668 669 /* 670 * If disk quotas is on, we make sure that the dquots do exist on disk, 671 * before we start any other transactions. Trying to do this later 672 * is messy. We don't care to take a readlock to look at the ids 673 * in inode here, because we can't hold it across the trans_reserve. 674 * If the IDs do change before we take the ilock, we're covered 675 * because the i_*dquot fields will get updated anyway. 676 */ 677 if (XFS_IS_QUOTA_ON(mp) && (mask & (ATTR_UID|ATTR_GID))) { 678 uint qflags = 0; 679 680 if ((mask & ATTR_UID) && XFS_IS_UQUOTA_ON(mp)) { 681 uid = from_vfsuid(mnt_userns, i_user_ns(inode), 682 iattr->ia_vfsuid); 683 qflags |= XFS_QMOPT_UQUOTA; 684 } else { 685 uid = inode->i_uid; 686 } 687 if ((mask & ATTR_GID) && XFS_IS_GQUOTA_ON(mp)) { 688 gid = from_vfsgid(mnt_userns, i_user_ns(inode), 689 iattr->ia_vfsgid); 690 qflags |= XFS_QMOPT_GQUOTA; 691 } else { 692 gid = inode->i_gid; 693 } 694 695 /* 696 * We take a reference when we initialize udqp and gdqp, 697 * so it is important that we never blindly double trip on 698 * the same variable. See xfs_create() for an example. 699 */ 700 ASSERT(udqp == NULL); 701 ASSERT(gdqp == NULL); 702 error = xfs_qm_vop_dqalloc(ip, uid, gid, ip->i_projid, 703 qflags, &udqp, &gdqp, NULL); 704 if (error) 705 return error; 706 } 707 708 error = xfs_trans_alloc_ichange(ip, udqp, gdqp, NULL, 709 has_capability_noaudit(current, CAP_FOWNER), &tp); 710 if (error) 711 goto out_dqrele; 712 713 /* 714 * Register quota modifications in the transaction. Must be the owner 715 * or privileged. These IDs could have changed since we last looked at 716 * them. But, we're assured that if the ownership did change while we 717 * didn't have the inode locked, inode's dquot(s) would have changed 718 * also. 719 */ 720 if (XFS_IS_UQUOTA_ON(mp) && 721 i_uid_needs_update(mnt_userns, iattr, inode)) { 722 ASSERT(udqp); 723 old_udqp = xfs_qm_vop_chown(tp, ip, &ip->i_udquot, udqp); 724 } 725 if (XFS_IS_GQUOTA_ON(mp) && 726 i_gid_needs_update(mnt_userns, iattr, inode)) { 727 ASSERT(xfs_has_pquotino(mp) || !XFS_IS_PQUOTA_ON(mp)); 728 ASSERT(gdqp); 729 old_gdqp = xfs_qm_vop_chown(tp, ip, &ip->i_gdquot, gdqp); 730 } 731 732 setattr_copy(mnt_userns, inode, iattr); 733 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE); 734 735 XFS_STATS_INC(mp, xs_ig_attrchg); 736 737 if (xfs_has_wsync(mp)) 738 xfs_trans_set_sync(tp); 739 error = xfs_trans_commit(tp); 740 741 /* 742 * Release any dquot(s) the inode had kept before chown. 743 */ 744 xfs_qm_dqrele(old_udqp); 745 xfs_qm_dqrele(old_gdqp); 746 xfs_qm_dqrele(udqp); 747 xfs_qm_dqrele(gdqp); 748 749 if (error) 750 return error; 751 752 /* 753 * XXX(hch): Updating the ACL entries is not atomic vs the i_mode 754 * update. We could avoid this with linked transactions 755 * and passing down the transaction pointer all the way 756 * to attr_set. No previous user of the generic 757 * Posix ACL code seems to care about this issue either. 758 */ 759 if (mask & ATTR_MODE) { 760 error = posix_acl_chmod(mnt_userns, inode, inode->i_mode); 761 if (error) 762 return error; 763 } 764 765 return 0; 766 767 out_dqrele: 768 xfs_qm_dqrele(udqp); 769 xfs_qm_dqrele(gdqp); 770 return error; 771 } 772 773 /* 774 * Truncate file. Must have write permission and not be a directory. 775 * 776 * Caution: The caller of this function is responsible for calling 777 * setattr_prepare() or otherwise verifying the change is fine. 778 */ 779 STATIC int 780 xfs_setattr_size( 781 struct user_namespace *mnt_userns, 782 struct xfs_inode *ip, 783 struct iattr *iattr) 784 { 785 struct xfs_mount *mp = ip->i_mount; 786 struct inode *inode = VFS_I(ip); 787 xfs_off_t oldsize, newsize; 788 struct xfs_trans *tp; 789 int error; 790 uint lock_flags = 0; 791 bool did_zeroing = false; 792 793 ASSERT(xfs_isilocked(ip, XFS_IOLOCK_EXCL)); 794 ASSERT(xfs_isilocked(ip, XFS_MMAPLOCK_EXCL)); 795 ASSERT(S_ISREG(inode->i_mode)); 796 ASSERT((iattr->ia_valid & (ATTR_UID|ATTR_GID|ATTR_ATIME|ATTR_ATIME_SET| 797 ATTR_MTIME_SET|ATTR_TIMES_SET)) == 0); 798 799 oldsize = inode->i_size; 800 newsize = iattr->ia_size; 801 802 /* 803 * Short circuit the truncate case for zero length files. 804 */ 805 if (newsize == 0 && oldsize == 0 && ip->i_df.if_nextents == 0) { 806 if (!(iattr->ia_valid & (ATTR_CTIME|ATTR_MTIME))) 807 return 0; 808 809 /* 810 * Use the regular setattr path to update the timestamps. 811 */ 812 iattr->ia_valid &= ~ATTR_SIZE; 813 return xfs_setattr_nonsize(mnt_userns, ip, iattr); 814 } 815 816 /* 817 * Make sure that the dquots are attached to the inode. 818 */ 819 error = xfs_qm_dqattach(ip); 820 if (error) 821 return error; 822 823 /* 824 * Wait for all direct I/O to complete. 825 */ 826 inode_dio_wait(inode); 827 828 /* 829 * File data changes must be complete before we start the transaction to 830 * modify the inode. This needs to be done before joining the inode to 831 * the transaction because the inode cannot be unlocked once it is a 832 * part of the transaction. 833 * 834 * Start with zeroing any data beyond EOF that we may expose on file 835 * extension, or zeroing out the rest of the block on a downward 836 * truncate. 837 */ 838 if (newsize > oldsize) { 839 trace_xfs_zero_eof(ip, oldsize, newsize - oldsize); 840 error = xfs_zero_range(ip, oldsize, newsize - oldsize, 841 &did_zeroing); 842 } else { 843 /* 844 * iomap won't detect a dirty page over an unwritten block (or a 845 * cow block over a hole) and subsequently skips zeroing the 846 * newly post-EOF portion of the page. Flush the new EOF to 847 * convert the block before the pagecache truncate. 848 */ 849 error = filemap_write_and_wait_range(inode->i_mapping, newsize, 850 newsize); 851 if (error) 852 return error; 853 error = xfs_truncate_page(ip, newsize, &did_zeroing); 854 } 855 856 if (error) 857 return error; 858 859 /* 860 * We've already locked out new page faults, so now we can safely remove 861 * pages from the page cache knowing they won't get refaulted until we 862 * drop the XFS_MMAP_EXCL lock after the extent manipulations are 863 * complete. The truncate_setsize() call also cleans partial EOF page 864 * PTEs on extending truncates and hence ensures sub-page block size 865 * filesystems are correctly handled, too. 866 * 867 * We have to do all the page cache truncate work outside the 868 * transaction context as the "lock" order is page lock->log space 869 * reservation as defined by extent allocation in the writeback path. 870 * Hence a truncate can fail with ENOMEM from xfs_trans_alloc(), but 871 * having already truncated the in-memory version of the file (i.e. made 872 * user visible changes). There's not much we can do about this, except 873 * to hope that the caller sees ENOMEM and retries the truncate 874 * operation. 875 * 876 * And we update in-core i_size and truncate page cache beyond newsize 877 * before writeback the [i_disk_size, newsize] range, so we're 878 * guaranteed not to write stale data past the new EOF on truncate down. 879 */ 880 truncate_setsize(inode, newsize); 881 882 /* 883 * We are going to log the inode size change in this transaction so 884 * any previous writes that are beyond the on disk EOF and the new 885 * EOF that have not been written out need to be written here. If we 886 * do not write the data out, we expose ourselves to the null files 887 * problem. Note that this includes any block zeroing we did above; 888 * otherwise those blocks may not be zeroed after a crash. 889 */ 890 if (did_zeroing || 891 (newsize > ip->i_disk_size && oldsize != ip->i_disk_size)) { 892 error = filemap_write_and_wait_range(VFS_I(ip)->i_mapping, 893 ip->i_disk_size, newsize - 1); 894 if (error) 895 return error; 896 } 897 898 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_itruncate, 0, 0, 0, &tp); 899 if (error) 900 return error; 901 902 lock_flags |= XFS_ILOCK_EXCL; 903 xfs_ilock(ip, XFS_ILOCK_EXCL); 904 xfs_trans_ijoin(tp, ip, 0); 905 906 /* 907 * Only change the c/mtime if we are changing the size or we are 908 * explicitly asked to change it. This handles the semantic difference 909 * between truncate() and ftruncate() as implemented in the VFS. 910 * 911 * The regular truncate() case without ATTR_CTIME and ATTR_MTIME is a 912 * special case where we need to update the times despite not having 913 * these flags set. For all other operations the VFS set these flags 914 * explicitly if it wants a timestamp update. 915 */ 916 if (newsize != oldsize && 917 !(iattr->ia_valid & (ATTR_CTIME | ATTR_MTIME))) { 918 iattr->ia_ctime = iattr->ia_mtime = 919 current_time(inode); 920 iattr->ia_valid |= ATTR_CTIME | ATTR_MTIME; 921 } 922 923 /* 924 * The first thing we do is set the size to new_size permanently on 925 * disk. This way we don't have to worry about anyone ever being able 926 * to look at the data being freed even in the face of a crash. 927 * What we're getting around here is the case where we free a block, it 928 * is allocated to another file, it is written to, and then we crash. 929 * If the new data gets written to the file but the log buffers 930 * containing the free and reallocation don't, then we'd end up with 931 * garbage in the blocks being freed. As long as we make the new size 932 * permanent before actually freeing any blocks it doesn't matter if 933 * they get written to. 934 */ 935 ip->i_disk_size = newsize; 936 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE); 937 938 if (newsize <= oldsize) { 939 error = xfs_itruncate_extents(&tp, ip, XFS_DATA_FORK, newsize); 940 if (error) 941 goto out_trans_cancel; 942 943 /* 944 * Truncated "down", so we're removing references to old data 945 * here - if we delay flushing for a long time, we expose 946 * ourselves unduly to the notorious NULL files problem. So, 947 * we mark this inode and flush it when the file is closed, 948 * and do not wait the usual (long) time for writeout. 949 */ 950 xfs_iflags_set(ip, XFS_ITRUNCATED); 951 952 /* A truncate down always removes post-EOF blocks. */ 953 xfs_inode_clear_eofblocks_tag(ip); 954 } 955 956 ASSERT(!(iattr->ia_valid & (ATTR_UID | ATTR_GID))); 957 setattr_copy(mnt_userns, inode, iattr); 958 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE); 959 960 XFS_STATS_INC(mp, xs_ig_attrchg); 961 962 if (xfs_has_wsync(mp)) 963 xfs_trans_set_sync(tp); 964 965 error = xfs_trans_commit(tp); 966 out_unlock: 967 if (lock_flags) 968 xfs_iunlock(ip, lock_flags); 969 return error; 970 971 out_trans_cancel: 972 xfs_trans_cancel(tp); 973 goto out_unlock; 974 } 975 976 int 977 xfs_vn_setattr_size( 978 struct user_namespace *mnt_userns, 979 struct dentry *dentry, 980 struct iattr *iattr) 981 { 982 struct xfs_inode *ip = XFS_I(d_inode(dentry)); 983 int error; 984 985 trace_xfs_setattr(ip); 986 987 error = xfs_vn_change_ok(mnt_userns, dentry, iattr); 988 if (error) 989 return error; 990 return xfs_setattr_size(mnt_userns, ip, iattr); 991 } 992 993 STATIC int 994 xfs_vn_setattr( 995 struct user_namespace *mnt_userns, 996 struct dentry *dentry, 997 struct iattr *iattr) 998 { 999 struct inode *inode = d_inode(dentry); 1000 struct xfs_inode *ip = XFS_I(inode); 1001 int error; 1002 1003 if (iattr->ia_valid & ATTR_SIZE) { 1004 uint iolock; 1005 1006 xfs_ilock(ip, XFS_MMAPLOCK_EXCL); 1007 iolock = XFS_IOLOCK_EXCL | XFS_MMAPLOCK_EXCL; 1008 1009 error = xfs_break_layouts(inode, &iolock, BREAK_UNMAP); 1010 if (error) { 1011 xfs_iunlock(ip, XFS_MMAPLOCK_EXCL); 1012 return error; 1013 } 1014 1015 error = xfs_vn_setattr_size(mnt_userns, dentry, iattr); 1016 xfs_iunlock(ip, XFS_MMAPLOCK_EXCL); 1017 } else { 1018 trace_xfs_setattr(ip); 1019 1020 error = xfs_vn_change_ok(mnt_userns, dentry, iattr); 1021 if (!error) 1022 error = xfs_setattr_nonsize(mnt_userns, ip, iattr); 1023 } 1024 1025 return error; 1026 } 1027 1028 STATIC int 1029 xfs_vn_update_time( 1030 struct inode *inode, 1031 struct timespec64 *now, 1032 int flags) 1033 { 1034 struct xfs_inode *ip = XFS_I(inode); 1035 struct xfs_mount *mp = ip->i_mount; 1036 int log_flags = XFS_ILOG_TIMESTAMP; 1037 struct xfs_trans *tp; 1038 int error; 1039 1040 trace_xfs_update_time(ip); 1041 1042 if (inode->i_sb->s_flags & SB_LAZYTIME) { 1043 if (!((flags & S_VERSION) && 1044 inode_maybe_inc_iversion(inode, false))) 1045 return generic_update_time(inode, now, flags); 1046 1047 /* Capture the iversion update that just occurred */ 1048 log_flags |= XFS_ILOG_CORE; 1049 } 1050 1051 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_fsyncts, 0, 0, 0, &tp); 1052 if (error) 1053 return error; 1054 1055 xfs_ilock(ip, XFS_ILOCK_EXCL); 1056 if (flags & S_CTIME) 1057 inode->i_ctime = *now; 1058 if (flags & S_MTIME) 1059 inode->i_mtime = *now; 1060 if (flags & S_ATIME) 1061 inode->i_atime = *now; 1062 1063 xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL); 1064 xfs_trans_log_inode(tp, ip, log_flags); 1065 return xfs_trans_commit(tp); 1066 } 1067 1068 STATIC int 1069 xfs_vn_fiemap( 1070 struct inode *inode, 1071 struct fiemap_extent_info *fieinfo, 1072 u64 start, 1073 u64 length) 1074 { 1075 int error; 1076 1077 xfs_ilock(XFS_I(inode), XFS_IOLOCK_SHARED); 1078 if (fieinfo->fi_flags & FIEMAP_FLAG_XATTR) { 1079 fieinfo->fi_flags &= ~FIEMAP_FLAG_XATTR; 1080 error = iomap_fiemap(inode, fieinfo, start, length, 1081 &xfs_xattr_iomap_ops); 1082 } else { 1083 error = iomap_fiemap(inode, fieinfo, start, length, 1084 &xfs_read_iomap_ops); 1085 } 1086 xfs_iunlock(XFS_I(inode), XFS_IOLOCK_SHARED); 1087 1088 return error; 1089 } 1090 1091 STATIC int 1092 xfs_vn_tmpfile( 1093 struct user_namespace *mnt_userns, 1094 struct inode *dir, 1095 struct file *file, 1096 umode_t mode) 1097 { 1098 int err = xfs_generic_create(mnt_userns, dir, file->f_path.dentry, mode, 0, file); 1099 1100 return finish_open_simple(file, err); 1101 } 1102 1103 static const struct inode_operations xfs_inode_operations = { 1104 .get_acl = xfs_get_acl, 1105 .set_acl = xfs_set_acl, 1106 .getattr = xfs_vn_getattr, 1107 .setattr = xfs_vn_setattr, 1108 .listxattr = xfs_vn_listxattr, 1109 .fiemap = xfs_vn_fiemap, 1110 .update_time = xfs_vn_update_time, 1111 .fileattr_get = xfs_fileattr_get, 1112 .fileattr_set = xfs_fileattr_set, 1113 }; 1114 1115 static const struct inode_operations xfs_dir_inode_operations = { 1116 .create = xfs_vn_create, 1117 .lookup = xfs_vn_lookup, 1118 .link = xfs_vn_link, 1119 .unlink = xfs_vn_unlink, 1120 .symlink = xfs_vn_symlink, 1121 .mkdir = xfs_vn_mkdir, 1122 /* 1123 * Yes, XFS uses the same method for rmdir and unlink. 1124 * 1125 * There are some subtile differences deeper in the code, 1126 * but we use S_ISDIR to check for those. 1127 */ 1128 .rmdir = xfs_vn_unlink, 1129 .mknod = xfs_vn_mknod, 1130 .rename = xfs_vn_rename, 1131 .get_acl = xfs_get_acl, 1132 .set_acl = xfs_set_acl, 1133 .getattr = xfs_vn_getattr, 1134 .setattr = xfs_vn_setattr, 1135 .listxattr = xfs_vn_listxattr, 1136 .update_time = xfs_vn_update_time, 1137 .tmpfile = xfs_vn_tmpfile, 1138 .fileattr_get = xfs_fileattr_get, 1139 .fileattr_set = xfs_fileattr_set, 1140 }; 1141 1142 static const struct inode_operations xfs_dir_ci_inode_operations = { 1143 .create = xfs_vn_create, 1144 .lookup = xfs_vn_ci_lookup, 1145 .link = xfs_vn_link, 1146 .unlink = xfs_vn_unlink, 1147 .symlink = xfs_vn_symlink, 1148 .mkdir = xfs_vn_mkdir, 1149 /* 1150 * Yes, XFS uses the same method for rmdir and unlink. 1151 * 1152 * There are some subtile differences deeper in the code, 1153 * but we use S_ISDIR to check for those. 1154 */ 1155 .rmdir = xfs_vn_unlink, 1156 .mknod = xfs_vn_mknod, 1157 .rename = xfs_vn_rename, 1158 .get_acl = xfs_get_acl, 1159 .set_acl = xfs_set_acl, 1160 .getattr = xfs_vn_getattr, 1161 .setattr = xfs_vn_setattr, 1162 .listxattr = xfs_vn_listxattr, 1163 .update_time = xfs_vn_update_time, 1164 .tmpfile = xfs_vn_tmpfile, 1165 .fileattr_get = xfs_fileattr_get, 1166 .fileattr_set = xfs_fileattr_set, 1167 }; 1168 1169 static const struct inode_operations xfs_symlink_inode_operations = { 1170 .get_link = xfs_vn_get_link, 1171 .getattr = xfs_vn_getattr, 1172 .setattr = xfs_vn_setattr, 1173 .listxattr = xfs_vn_listxattr, 1174 .update_time = xfs_vn_update_time, 1175 }; 1176 1177 /* Figure out if this file actually supports DAX. */ 1178 static bool 1179 xfs_inode_supports_dax( 1180 struct xfs_inode *ip) 1181 { 1182 struct xfs_mount *mp = ip->i_mount; 1183 1184 /* Only supported on regular files. */ 1185 if (!S_ISREG(VFS_I(ip)->i_mode)) 1186 return false; 1187 1188 /* Only supported on non-reflinked files. */ 1189 if (xfs_is_reflink_inode(ip)) 1190 return false; 1191 1192 /* Block size must match page size */ 1193 if (mp->m_sb.sb_blocksize != PAGE_SIZE) 1194 return false; 1195 1196 /* Device has to support DAX too. */ 1197 return xfs_inode_buftarg(ip)->bt_daxdev != NULL; 1198 } 1199 1200 static bool 1201 xfs_inode_should_enable_dax( 1202 struct xfs_inode *ip) 1203 { 1204 if (!IS_ENABLED(CONFIG_FS_DAX)) 1205 return false; 1206 if (xfs_has_dax_never(ip->i_mount)) 1207 return false; 1208 if (!xfs_inode_supports_dax(ip)) 1209 return false; 1210 if (xfs_has_dax_always(ip->i_mount)) 1211 return true; 1212 if (ip->i_diflags2 & XFS_DIFLAG2_DAX) 1213 return true; 1214 return false; 1215 } 1216 1217 void 1218 xfs_diflags_to_iflags( 1219 struct xfs_inode *ip, 1220 bool init) 1221 { 1222 struct inode *inode = VFS_I(ip); 1223 unsigned int xflags = xfs_ip2xflags(ip); 1224 unsigned int flags = 0; 1225 1226 ASSERT(!(IS_DAX(inode) && init)); 1227 1228 if (xflags & FS_XFLAG_IMMUTABLE) 1229 flags |= S_IMMUTABLE; 1230 if (xflags & FS_XFLAG_APPEND) 1231 flags |= S_APPEND; 1232 if (xflags & FS_XFLAG_SYNC) 1233 flags |= S_SYNC; 1234 if (xflags & FS_XFLAG_NOATIME) 1235 flags |= S_NOATIME; 1236 if (init && xfs_inode_should_enable_dax(ip)) 1237 flags |= S_DAX; 1238 1239 /* 1240 * S_DAX can only be set during inode initialization and is never set by 1241 * the VFS, so we cannot mask off S_DAX in i_flags. 1242 */ 1243 inode->i_flags &= ~(S_IMMUTABLE | S_APPEND | S_SYNC | S_NOATIME); 1244 inode->i_flags |= flags; 1245 } 1246 1247 /* 1248 * Initialize the Linux inode. 1249 * 1250 * When reading existing inodes from disk this is called directly from xfs_iget, 1251 * when creating a new inode it is called from xfs_init_new_inode after setting 1252 * up the inode. These callers have different criteria for clearing XFS_INEW, so 1253 * leave it up to the caller to deal with unlocking the inode appropriately. 1254 */ 1255 void 1256 xfs_setup_inode( 1257 struct xfs_inode *ip) 1258 { 1259 struct inode *inode = &ip->i_vnode; 1260 gfp_t gfp_mask; 1261 1262 inode->i_ino = ip->i_ino; 1263 inode->i_state |= I_NEW; 1264 1265 inode_sb_list_add(inode); 1266 /* make the inode look hashed for the writeback code */ 1267 inode_fake_hash(inode); 1268 1269 i_size_write(inode, ip->i_disk_size); 1270 xfs_diflags_to_iflags(ip, true); 1271 1272 if (S_ISDIR(inode->i_mode)) { 1273 /* 1274 * We set the i_rwsem class here to avoid potential races with 1275 * lockdep_annotate_inode_mutex_key() reinitialising the lock 1276 * after a filehandle lookup has already found the inode in 1277 * cache before it has been unlocked via unlock_new_inode(). 1278 */ 1279 lockdep_set_class(&inode->i_rwsem, 1280 &inode->i_sb->s_type->i_mutex_dir_key); 1281 lockdep_set_class(&ip->i_lock.mr_lock, &xfs_dir_ilock_class); 1282 } else { 1283 lockdep_set_class(&ip->i_lock.mr_lock, &xfs_nondir_ilock_class); 1284 } 1285 1286 /* 1287 * Ensure all page cache allocations are done from GFP_NOFS context to 1288 * prevent direct reclaim recursion back into the filesystem and blowing 1289 * stacks or deadlocking. 1290 */ 1291 gfp_mask = mapping_gfp_mask(inode->i_mapping); 1292 mapping_set_gfp_mask(inode->i_mapping, (gfp_mask & ~(__GFP_FS))); 1293 1294 /* 1295 * If there is no attribute fork no ACL can exist on this inode, 1296 * and it can't have any file capabilities attached to it either. 1297 */ 1298 if (!xfs_inode_has_attr_fork(ip)) { 1299 inode_has_no_xattr(inode); 1300 cache_no_acl(inode); 1301 } 1302 } 1303 1304 void 1305 xfs_setup_iops( 1306 struct xfs_inode *ip) 1307 { 1308 struct inode *inode = &ip->i_vnode; 1309 1310 switch (inode->i_mode & S_IFMT) { 1311 case S_IFREG: 1312 inode->i_op = &xfs_inode_operations; 1313 inode->i_fop = &xfs_file_operations; 1314 if (IS_DAX(inode)) 1315 inode->i_mapping->a_ops = &xfs_dax_aops; 1316 else 1317 inode->i_mapping->a_ops = &xfs_address_space_operations; 1318 break; 1319 case S_IFDIR: 1320 if (xfs_has_asciici(XFS_M(inode->i_sb))) 1321 inode->i_op = &xfs_dir_ci_inode_operations; 1322 else 1323 inode->i_op = &xfs_dir_inode_operations; 1324 inode->i_fop = &xfs_dir_file_operations; 1325 break; 1326 case S_IFLNK: 1327 inode->i_op = &xfs_symlink_inode_operations; 1328 break; 1329 default: 1330 inode->i_op = &xfs_inode_operations; 1331 init_special_inode(inode, inode->i_mode, inode->i_rdev); 1332 break; 1333 } 1334 } 1335