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1// SPDX-License-Identifier: GPL-2.02/*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_trans_space.h"21#include "xfs_bmap_btree.h"22#include "xfs_trace.h"23#include "xfs_icache.h"24#include "xfs_symlink.h"25#include "xfs_dir2.h"26#include "xfs_iomap.h"27#include "xfs_error.h"28#include "xfs_ioctl.h"29#include "xfs_xattr.h"30#include "xfs_file.h"31#include "xfs_bmap.h"32 33#include <linux/posix_acl.h>34#include <linux/security.h>35#include <linux/iversion.h>36#include <linux/fiemap.h>37 38/*39 * Directories have different lock order w.r.t. mmap_lock compared to regular40 * files. This is due to readdir potentially triggering page faults on a user41 * buffer inside filldir(), and this happens with the ilock on the directory42 * held. For regular files, the lock order is the other way around - the43 * mmap_lock is taken during the page fault, and then we lock the ilock to do44 * block mapping. Hence we need a different class for the directory ilock so45 * that lockdep can tell them apart.46 */47static struct lock_class_key xfs_nondir_ilock_class;48static struct lock_class_key xfs_dir_ilock_class;49 50static int51xfs_initxattrs(52 struct inode *inode,53 const struct xattr *xattr_array,54 void *fs_info)55{56 const struct xattr *xattr;57 struct xfs_inode *ip = XFS_I(inode);58 int error = 0;59 60 for (xattr = xattr_array; xattr->name != NULL; xattr++) {61 struct xfs_da_args args = {62 .dp = ip,63 .attr_filter = XFS_ATTR_SECURE,64 .name = xattr->name,65 .namelen = strlen(xattr->name),66 .value = xattr->value,67 .valuelen = xattr->value_len,68 };69 error = xfs_attr_change(&args, XFS_ATTRUPDATE_UPSERT);70 if (error < 0)71 break;72 }73 return error;74}75 76/*77 * Hook in SELinux. This is not quite correct yet, what we really need78 * here (as we do for default ACLs) is a mechanism by which creation of79 * these attrs can be journalled at inode creation time (along with the80 * inode, of course, such that log replay can't cause these to be lost).81 */82int83xfs_inode_init_security(84 struct inode *inode,85 struct inode *dir,86 const struct qstr *qstr)87{88 return security_inode_init_security(inode, dir, qstr,89 &xfs_initxattrs, NULL);90}91 92static void93xfs_dentry_to_name(94 struct xfs_name *namep,95 struct dentry *dentry)96{97 namep->name = dentry->d_name.name;98 namep->len = dentry->d_name.len;99 namep->type = XFS_DIR3_FT_UNKNOWN;100}101 102static int103xfs_dentry_mode_to_name(104 struct xfs_name *namep,105 struct dentry *dentry,106 int mode)107{108 namep->name = dentry->d_name.name;109 namep->len = dentry->d_name.len;110 namep->type = xfs_mode_to_ftype(mode);111 112 if (unlikely(namep->type == XFS_DIR3_FT_UNKNOWN))113 return -EFSCORRUPTED;114 115 return 0;116}117 118STATIC void119xfs_cleanup_inode(120 struct inode *dir,121 struct inode *inode,122 struct dentry *dentry)123{124 struct xfs_name teardown;125 126 /* Oh, the horror.127 * If we can't add the ACL or we fail in128 * xfs_inode_init_security we must back out.129 * ENOSPC can hit here, among other things.130 */131 xfs_dentry_to_name(&teardown, dentry);132 133 xfs_remove(XFS_I(dir), &teardown, XFS_I(inode));134}135 136/*137 * Check to see if we are likely to need an extended attribute to be added to138 * the inode we are about to allocate. This allows the attribute fork to be139 * created during the inode allocation, reducing the number of transactions we140 * need to do in this fast path.141 *142 * The security checks are optimistic, but not guaranteed. The two LSMs that143 * require xattrs to be added here (selinux and smack) are also the only two144 * LSMs that add a sb->s_security structure to the superblock. Hence if security145 * is enabled and sb->s_security is set, we have a pretty good idea that we are146 * going to be asked to add a security xattr immediately after allocating the147 * xfs inode and instantiating the VFS inode.148 */149static inline bool150xfs_create_need_xattr(151 struct inode *dir,152 struct posix_acl *default_acl,153 struct posix_acl *acl)154{155 if (acl)156 return true;157 if (default_acl)158 return true;159#if IS_ENABLED(CONFIG_SECURITY)160 if (dir->i_sb->s_security)161 return true;162#endif163 return false;164}165 166 167STATIC int168xfs_generic_create(169 struct mnt_idmap *idmap,170 struct inode *dir,171 struct dentry *dentry,172 umode_t mode,173 dev_t rdev,174 struct file *tmpfile) /* unnamed file */175{176 struct xfs_icreate_args args = {177 .idmap = idmap,178 .pip = XFS_I(dir),179 .rdev = rdev,180 .mode = mode,181 };182 struct inode *inode;183 struct xfs_inode *ip = NULL;184 struct posix_acl *default_acl, *acl;185 struct xfs_name name;186 int error;187 188 /*189 * Irix uses Missed'em'V split, but doesn't want to see190 * the upper 5 bits of (14bit) major.191 */192 if (S_ISCHR(args.mode) || S_ISBLK(args.mode)) {193 if (unlikely(!sysv_valid_dev(args.rdev) ||194 MAJOR(args.rdev) & ~0x1ff))195 return -EINVAL;196 } else {197 args.rdev = 0;198 }199 200 error = posix_acl_create(dir, &args.mode, &default_acl, &acl);201 if (error)202 return error;203 204 /* Verify mode is valid also for tmpfile case */205 error = xfs_dentry_mode_to_name(&name, dentry, args.mode);206 if (unlikely(error))207 goto out_free_acl;208 209 if (!tmpfile) {210 if (xfs_create_need_xattr(dir, default_acl, acl))211 args.flags |= XFS_ICREATE_INIT_XATTRS;212 213 error = xfs_create(&args, &name, &ip);214 } else {215 args.flags |= XFS_ICREATE_TMPFILE;216 217 /*218 * If this temporary file will not be linkable, don't bother219 * creating an attr fork to receive a parent pointer.220 */221 if (tmpfile->f_flags & O_EXCL)222 args.flags |= XFS_ICREATE_UNLINKABLE;223 224 error = xfs_create_tmpfile(&args, &ip);225 }226 if (unlikely(error))227 goto out_free_acl;228 229 inode = VFS_I(ip);230 231 error = xfs_inode_init_security(inode, dir, &dentry->d_name);232 if (unlikely(error))233 goto out_cleanup_inode;234 235 if (default_acl) {236 error = __xfs_set_acl(inode, default_acl, ACL_TYPE_DEFAULT);237 if (error)238 goto out_cleanup_inode;239 }240 if (acl) {241 error = __xfs_set_acl(inode, acl, ACL_TYPE_ACCESS);242 if (error)243 goto out_cleanup_inode;244 }245 246 xfs_setup_iops(ip);247 248 if (tmpfile) {249 /*250 * The VFS requires that any inode fed to d_tmpfile must have251 * nlink == 1 so that it can decrement the nlink in d_tmpfile.252 * However, we created the temp file with nlink == 0 because253 * we're not allowed to put an inode with nlink > 0 on the254 * unlinked list. Therefore we have to set nlink to 1 so that255 * d_tmpfile can immediately set it back to zero.256 */257 set_nlink(inode, 1);258 d_tmpfile(tmpfile, inode);259 } else260 d_instantiate(dentry, inode);261 262 xfs_finish_inode_setup(ip);263 264 out_free_acl:265 posix_acl_release(default_acl);266 posix_acl_release(acl);267 return error;268 269 out_cleanup_inode:270 xfs_finish_inode_setup(ip);271 if (!tmpfile)272 xfs_cleanup_inode(dir, inode, dentry);273 xfs_irele(ip);274 goto out_free_acl;275}276 277STATIC int278xfs_vn_mknod(279 struct mnt_idmap *idmap,280 struct inode *dir,281 struct dentry *dentry,282 umode_t mode,283 dev_t rdev)284{285 return xfs_generic_create(idmap, dir, dentry, mode, rdev, NULL);286}287 288STATIC int289xfs_vn_create(290 struct mnt_idmap *idmap,291 struct inode *dir,292 struct dentry *dentry,293 umode_t mode,294 bool flags)295{296 return xfs_generic_create(idmap, dir, dentry, mode, 0, NULL);297}298 299STATIC int300xfs_vn_mkdir(301 struct mnt_idmap *idmap,302 struct inode *dir,303 struct dentry *dentry,304 umode_t mode)305{306 return xfs_generic_create(idmap, dir, dentry, mode | S_IFDIR, 0, NULL);307}308 309STATIC struct dentry *310xfs_vn_lookup(311 struct inode *dir,312 struct dentry *dentry,313 unsigned int flags)314{315 struct inode *inode;316 struct xfs_inode *cip;317 struct xfs_name name;318 int error;319 320 if (dentry->d_name.len >= MAXNAMELEN)321 return ERR_PTR(-ENAMETOOLONG);322 323 xfs_dentry_to_name(&name, dentry);324 error = xfs_lookup(XFS_I(dir), &name, &cip, NULL);325 if (likely(!error))326 inode = VFS_I(cip);327 else if (likely(error == -ENOENT))328 inode = NULL;329 else330 inode = ERR_PTR(error);331 return d_splice_alias(inode, dentry);332}333 334STATIC struct dentry *335xfs_vn_ci_lookup(336 struct inode *dir,337 struct dentry *dentry,338 unsigned int flags)339{340 struct xfs_inode *ip;341 struct xfs_name xname;342 struct xfs_name ci_name;343 struct qstr dname;344 int error;345 346 if (dentry->d_name.len >= MAXNAMELEN)347 return ERR_PTR(-ENAMETOOLONG);348 349 xfs_dentry_to_name(&xname, dentry);350 error = xfs_lookup(XFS_I(dir), &xname, &ip, &ci_name);351 if (unlikely(error)) {352 if (unlikely(error != -ENOENT))353 return ERR_PTR(error);354 /*355 * call d_add(dentry, NULL) here when d_drop_negative_children356 * is called in xfs_vn_mknod (ie. allow negative dentries357 * with CI filesystems).358 */359 return NULL;360 }361 362 /* if exact match, just splice and exit */363 if (!ci_name.name)364 return d_splice_alias(VFS_I(ip), dentry);365 366 /* else case-insensitive match... */367 dname.name = ci_name.name;368 dname.len = ci_name.len;369 dentry = d_add_ci(dentry, VFS_I(ip), &dname);370 kfree(ci_name.name);371 return dentry;372}373 374STATIC int375xfs_vn_link(376 struct dentry *old_dentry,377 struct inode *dir,378 struct dentry *dentry)379{380 struct inode *inode = d_inode(old_dentry);381 struct xfs_name name;382 int error;383 384 error = xfs_dentry_mode_to_name(&name, dentry, inode->i_mode);385 if (unlikely(error))386 return error;387 388 if (IS_PRIVATE(inode))389 return -EPERM;390 391 error = xfs_link(XFS_I(dir), XFS_I(inode), &name);392 if (unlikely(error))393 return error;394 395 ihold(inode);396 d_instantiate(dentry, inode);397 return 0;398}399 400STATIC int401xfs_vn_unlink(402 struct inode *dir,403 struct dentry *dentry)404{405 struct xfs_name name;406 int error;407 408 xfs_dentry_to_name(&name, dentry);409 410 error = xfs_remove(XFS_I(dir), &name, XFS_I(d_inode(dentry)));411 if (error)412 return error;413 414 /*415 * With unlink, the VFS makes the dentry "negative": no inode,416 * but still hashed. This is incompatible with case-insensitive417 * mode, so invalidate (unhash) the dentry in CI-mode.418 */419 if (xfs_has_asciici(XFS_M(dir->i_sb)))420 d_invalidate(dentry);421 return 0;422}423 424STATIC int425xfs_vn_symlink(426 struct mnt_idmap *idmap,427 struct inode *dir,428 struct dentry *dentry,429 const char *symname)430{431 struct inode *inode;432 struct xfs_inode *cip = NULL;433 struct xfs_name name;434 int error;435 umode_t mode;436 437 mode = S_IFLNK |438 (irix_symlink_mode ? 0777 & ~current_umask() : S_IRWXUGO);439 error = xfs_dentry_mode_to_name(&name, dentry, mode);440 if (unlikely(error))441 goto out;442 443 error = xfs_symlink(idmap, XFS_I(dir), &name, symname, mode, &cip);444 if (unlikely(error))445 goto out;446 447 inode = VFS_I(cip);448 449 error = xfs_inode_init_security(inode, dir, &dentry->d_name);450 if (unlikely(error))451 goto out_cleanup_inode;452 453 xfs_setup_iops(cip);454 455 d_instantiate(dentry, inode);456 xfs_finish_inode_setup(cip);457 return 0;458 459 out_cleanup_inode:460 xfs_finish_inode_setup(cip);461 xfs_cleanup_inode(dir, inode, dentry);462 xfs_irele(cip);463 out:464 return error;465}466 467STATIC int468xfs_vn_rename(469 struct mnt_idmap *idmap,470 struct inode *odir,471 struct dentry *odentry,472 struct inode *ndir,473 struct dentry *ndentry,474 unsigned int flags)475{476 struct inode *new_inode = d_inode(ndentry);477 int omode = 0;478 int error;479 struct xfs_name oname;480 struct xfs_name nname;481 482 if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE | RENAME_WHITEOUT))483 return -EINVAL;484 485 /* if we are exchanging files, we need to set i_mode of both files */486 if (flags & RENAME_EXCHANGE)487 omode = d_inode(ndentry)->i_mode;488 489 error = xfs_dentry_mode_to_name(&oname, odentry, omode);490 if (omode && unlikely(error))491 return error;492 493 error = xfs_dentry_mode_to_name(&nname, ndentry,494 d_inode(odentry)->i_mode);495 if (unlikely(error))496 return error;497 498 return xfs_rename(idmap, XFS_I(odir), &oname,499 XFS_I(d_inode(odentry)), XFS_I(ndir), &nname,500 new_inode ? XFS_I(new_inode) : NULL, flags);501}502 503/*504 * careful here - this function can get called recursively, so505 * we need to be very careful about how much stack we use.506 * uio is kmalloced for this reason...507 */508STATIC const char *509xfs_vn_get_link(510 struct dentry *dentry,511 struct inode *inode,512 struct delayed_call *done)513{514 char *link;515 int error = -ENOMEM;516 517 if (!dentry)518 return ERR_PTR(-ECHILD);519 520 link = kmalloc(XFS_SYMLINK_MAXLEN+1, GFP_KERNEL);521 if (!link)522 goto out_err;523 524 error = xfs_readlink(XFS_I(d_inode(dentry)), link);525 if (unlikely(error))526 goto out_kfree;527 528 set_delayed_call(done, kfree_link, link);529 return link;530 531 out_kfree:532 kfree(link);533 out_err:534 return ERR_PTR(error);535}536 537static uint32_t538xfs_stat_blksize(539 struct xfs_inode *ip)540{541 struct xfs_mount *mp = ip->i_mount;542 543 /*544 * If the file blocks are being allocated from a realtime volume, then545 * always return the realtime extent size.546 */547 if (XFS_IS_REALTIME_INODE(ip))548 return XFS_FSB_TO_B(mp, xfs_get_extsz_hint(ip) ? : 1);549 550 /*551 * Allow large block sizes to be reported to userspace programs if the552 * "largeio" mount option is used.553 *554 * If compatibility mode is specified, simply return the basic unit of555 * caching so that we don't get inefficient read/modify/write I/O from556 * user apps. Otherwise....557 *558 * If the underlying volume is a stripe, then return the stripe width in559 * bytes as the recommended I/O size. It is not a stripe and we've set a560 * default buffered I/O size, return that, otherwise return the compat561 * default.562 */563 if (xfs_has_large_iosize(mp)) {564 if (mp->m_swidth)565 return XFS_FSB_TO_B(mp, mp->m_swidth);566 if (xfs_has_allocsize(mp))567 return 1U << mp->m_allocsize_log;568 }569 570 return max_t(uint32_t, PAGE_SIZE, mp->m_sb.sb_blocksize);571}572 573STATIC int574xfs_vn_getattr(575 struct mnt_idmap *idmap,576 const struct path *path,577 struct kstat *stat,578 u32 request_mask,579 unsigned int query_flags)580{581 struct inode *inode = d_inode(path->dentry);582 struct xfs_inode *ip = XFS_I(inode);583 struct xfs_mount *mp = ip->i_mount;584 vfsuid_t vfsuid = i_uid_into_vfsuid(idmap, inode);585 vfsgid_t vfsgid = i_gid_into_vfsgid(idmap, inode);586 587 trace_xfs_getattr(ip);588 589 if (xfs_is_shutdown(mp))590 return -EIO;591 592 stat->size = XFS_ISIZE(ip);593 stat->dev = inode->i_sb->s_dev;594 stat->mode = inode->i_mode;595 stat->nlink = inode->i_nlink;596 stat->uid = vfsuid_into_kuid(vfsuid);597 stat->gid = vfsgid_into_kgid(vfsgid);598 stat->ino = ip->i_ino;599 stat->atime = inode_get_atime(inode);600 stat->mtime = inode_get_mtime(inode);601 stat->ctime = inode_get_ctime(inode);602 stat->blocks = XFS_FSB_TO_BB(mp, ip->i_nblocks + ip->i_delayed_blks);603 604 if (xfs_has_v3inodes(mp)) {605 if (request_mask & STATX_BTIME) {606 stat->result_mask |= STATX_BTIME;607 stat->btime = ip->i_crtime;608 }609 }610 611 if ((request_mask & STATX_CHANGE_COOKIE) && IS_I_VERSION(inode)) {612 stat->change_cookie = inode_query_iversion(inode);613 stat->result_mask |= STATX_CHANGE_COOKIE;614 }615 616 /*617 * Note: If you add another clause to set an attribute flag, please618 * update attributes_mask below.619 */620 if (ip->i_diflags & XFS_DIFLAG_IMMUTABLE)621 stat->attributes |= STATX_ATTR_IMMUTABLE;622 if (ip->i_diflags & XFS_DIFLAG_APPEND)623 stat->attributes |= STATX_ATTR_APPEND;624 if (ip->i_diflags & XFS_DIFLAG_NODUMP)625 stat->attributes |= STATX_ATTR_NODUMP;626 627 stat->attributes_mask |= (STATX_ATTR_IMMUTABLE |628 STATX_ATTR_APPEND |629 STATX_ATTR_NODUMP);630 631 switch (inode->i_mode & S_IFMT) {632 case S_IFBLK:633 case S_IFCHR:634 stat->blksize = BLKDEV_IOSIZE;635 stat->rdev = inode->i_rdev;636 break;637 case S_IFREG:638 if (request_mask & STATX_DIOALIGN) {639 struct xfs_buftarg *target = xfs_inode_buftarg(ip);640 struct block_device *bdev = target->bt_bdev;641 642 stat->result_mask |= STATX_DIOALIGN;643 stat->dio_mem_align = bdev_dma_alignment(bdev) + 1;644 stat->dio_offset_align = bdev_logical_block_size(bdev);645 }646 fallthrough;647 default:648 stat->blksize = xfs_stat_blksize(ip);649 stat->rdev = 0;650 break;651 }652 653 return 0;654}655 656static int657xfs_vn_change_ok(658 struct mnt_idmap *idmap,659 struct dentry *dentry,660 struct iattr *iattr)661{662 struct xfs_mount *mp = XFS_I(d_inode(dentry))->i_mount;663 664 if (xfs_is_readonly(mp))665 return -EROFS;666 667 if (xfs_is_shutdown(mp))668 return -EIO;669 670 return setattr_prepare(idmap, dentry, iattr);671}672 673/*674 * Set non-size attributes of an inode.675 *676 * Caution: The caller of this function is responsible for calling677 * setattr_prepare() or otherwise verifying the change is fine.678 */679static int680xfs_setattr_nonsize(681 struct mnt_idmap *idmap,682 struct dentry *dentry,683 struct xfs_inode *ip,684 struct iattr *iattr)685{686 xfs_mount_t *mp = ip->i_mount;687 struct inode *inode = VFS_I(ip);688 int mask = iattr->ia_valid;689 xfs_trans_t *tp;690 int error;691 kuid_t uid = GLOBAL_ROOT_UID;692 kgid_t gid = GLOBAL_ROOT_GID;693 struct xfs_dquot *udqp = NULL, *gdqp = NULL;694 struct xfs_dquot *old_udqp = NULL, *old_gdqp = NULL;695 696 ASSERT((mask & ATTR_SIZE) == 0);697 698 /*699 * If disk quotas is on, we make sure that the dquots do exist on disk,700 * before we start any other transactions. Trying to do this later701 * is messy. We don't care to take a readlock to look at the ids702 * in inode here, because we can't hold it across the trans_reserve.703 * If the IDs do change before we take the ilock, we're covered704 * because the i_*dquot fields will get updated anyway.705 */706 if (XFS_IS_QUOTA_ON(mp) && (mask & (ATTR_UID|ATTR_GID))) {707 uint qflags = 0;708 709 if ((mask & ATTR_UID) && XFS_IS_UQUOTA_ON(mp)) {710 uid = from_vfsuid(idmap, i_user_ns(inode),711 iattr->ia_vfsuid);712 qflags |= XFS_QMOPT_UQUOTA;713 } else {714 uid = inode->i_uid;715 }716 if ((mask & ATTR_GID) && XFS_IS_GQUOTA_ON(mp)) {717 gid = from_vfsgid(idmap, i_user_ns(inode),718 iattr->ia_vfsgid);719 qflags |= XFS_QMOPT_GQUOTA;720 } else {721 gid = inode->i_gid;722 }723 724 /*725 * We take a reference when we initialize udqp and gdqp,726 * so it is important that we never blindly double trip on727 * the same variable. See xfs_create() for an example.728 */729 ASSERT(udqp == NULL);730 ASSERT(gdqp == NULL);731 error = xfs_qm_vop_dqalloc(ip, uid, gid, ip->i_projid,732 qflags, &udqp, &gdqp, NULL);733 if (error)734 return error;735 }736 737 error = xfs_trans_alloc_ichange(ip, udqp, gdqp, NULL,738 has_capability_noaudit(current, CAP_FOWNER), &tp);739 if (error)740 goto out_dqrele;741 742 /*743 * Register quota modifications in the transaction. Must be the owner744 * or privileged. These IDs could have changed since we last looked at745 * them. But, we're assured that if the ownership did change while we746 * didn't have the inode locked, inode's dquot(s) would have changed747 * also.748 */749 if (XFS_IS_UQUOTA_ON(mp) &&750 i_uid_needs_update(idmap, iattr, inode)) {751 ASSERT(udqp);752 old_udqp = xfs_qm_vop_chown(tp, ip, &ip->i_udquot, udqp);753 }754 if (XFS_IS_GQUOTA_ON(mp) &&755 i_gid_needs_update(idmap, iattr, inode)) {756 ASSERT(xfs_has_pquotino(mp) || !XFS_IS_PQUOTA_ON(mp));757 ASSERT(gdqp);758 old_gdqp = xfs_qm_vop_chown(tp, ip, &ip->i_gdquot, gdqp);759 }760 761 setattr_copy(idmap, inode, iattr);762 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);763 764 XFS_STATS_INC(mp, xs_ig_attrchg);765 766 if (xfs_has_wsync(mp))767 xfs_trans_set_sync(tp);768 error = xfs_trans_commit(tp);769 770 /*771 * Release any dquot(s) the inode had kept before chown.772 */773 xfs_qm_dqrele(old_udqp);774 xfs_qm_dqrele(old_gdqp);775 xfs_qm_dqrele(udqp);776 xfs_qm_dqrele(gdqp);777 778 if (error)779 return error;780 781 /*782 * XXX(hch): Updating the ACL entries is not atomic vs the i_mode783 * update. We could avoid this with linked transactions784 * and passing down the transaction pointer all the way785 * to attr_set. No previous user of the generic786 * Posix ACL code seems to care about this issue either.787 */788 if (mask & ATTR_MODE) {789 error = posix_acl_chmod(idmap, dentry, inode->i_mode);790 if (error)791 return error;792 }793 794 return 0;795 796out_dqrele:797 xfs_qm_dqrele(udqp);798 xfs_qm_dqrele(gdqp);799 return error;800}801 802/*803 * Truncate file. Must have write permission and not be a directory.804 *805 * Caution: The caller of this function is responsible for calling806 * setattr_prepare() or otherwise verifying the change is fine.807 */808STATIC int809xfs_setattr_size(810 struct mnt_idmap *idmap,811 struct dentry *dentry,812 struct xfs_inode *ip,813 struct iattr *iattr)814{815 struct xfs_mount *mp = ip->i_mount;816 struct inode *inode = VFS_I(ip);817 xfs_off_t oldsize, newsize;818 struct xfs_trans *tp;819 int error;820 uint lock_flags = 0;821 uint resblks = 0;822 bool did_zeroing = false;823 824 xfs_assert_ilocked(ip, XFS_IOLOCK_EXCL | XFS_MMAPLOCK_EXCL);825 ASSERT(S_ISREG(inode->i_mode));826 ASSERT((iattr->ia_valid & (ATTR_UID|ATTR_GID|ATTR_ATIME|ATTR_ATIME_SET|827 ATTR_MTIME_SET|ATTR_TIMES_SET)) == 0);828 829 oldsize = inode->i_size;830 newsize = iattr->ia_size;831 832 /*833 * Short circuit the truncate case for zero length files.834 */835 if (newsize == 0 && oldsize == 0 && ip->i_df.if_nextents == 0) {836 if (!(iattr->ia_valid & (ATTR_CTIME|ATTR_MTIME)))837 return 0;838 839 /*840 * Use the regular setattr path to update the timestamps.841 */842 iattr->ia_valid &= ~ATTR_SIZE;843 return xfs_setattr_nonsize(idmap, dentry, ip, iattr);844 }845 846 /*847 * Make sure that the dquots are attached to the inode.848 */849 error = xfs_qm_dqattach(ip);850 if (error)851 return error;852 853 /*854 * Wait for all direct I/O to complete.855 */856 inode_dio_wait(inode);857 858 /*859 * File data changes must be complete before we start the transaction to860 * modify the inode. This needs to be done before joining the inode to861 * the transaction because the inode cannot be unlocked once it is a862 * part of the transaction.863 *864 * Start with zeroing any data beyond EOF that we may expose on file865 * extension, or zeroing out the rest of the block on a downward866 * truncate.867 */868 if (newsize > oldsize) {869 trace_xfs_zero_eof(ip, oldsize, newsize - oldsize);870 error = xfs_zero_range(ip, oldsize, newsize - oldsize,871 &did_zeroing);872 } else {873 error = xfs_truncate_page(ip, newsize, &did_zeroing);874 }875 876 if (error)877 return error;878 879 /*880 * We've already locked out new page faults, so now we can safely remove881 * pages from the page cache knowing they won't get refaulted until we882 * drop the XFS_MMAP_EXCL lock after the extent manipulations are883 * complete. The truncate_setsize() call also cleans partial EOF page884 * PTEs on extending truncates and hence ensures sub-page block size885 * filesystems are correctly handled, too.886 *887 * We have to do all the page cache truncate work outside the888 * transaction context as the "lock" order is page lock->log space889 * reservation as defined by extent allocation in the writeback path.890 * Hence a truncate can fail with ENOMEM from xfs_trans_alloc(), but891 * having already truncated the in-memory version of the file (i.e. made892 * user visible changes). There's not much we can do about this, except893 * to hope that the caller sees ENOMEM and retries the truncate894 * operation.895 *896 * And we update in-core i_size and truncate page cache beyond newsize897 * before writeback the [i_disk_size, newsize] range, so we're898 * guaranteed not to write stale data past the new EOF on truncate down.899 */900 truncate_setsize(inode, newsize);901 902 /*903 * We are going to log the inode size change in this transaction so904 * any previous writes that are beyond the on disk EOF and the new905 * EOF that have not been written out need to be written here. If we906 * do not write the data out, we expose ourselves to the null files907 * problem. Note that this includes any block zeroing we did above;908 * otherwise those blocks may not be zeroed after a crash.909 */910 if (did_zeroing ||911 (newsize > ip->i_disk_size && oldsize != ip->i_disk_size)) {912 error = filemap_write_and_wait_range(VFS_I(ip)->i_mapping,913 ip->i_disk_size, newsize - 1);914 if (error)915 return error;916 }917 918 /*919 * For realtime inode with more than one block rtextsize, we need the920 * block reservation for bmap btree block allocations/splits that can921 * happen since it could split the tail written extent and convert the922 * right beyond EOF one to unwritten.923 */924 if (xfs_inode_has_bigrtalloc(ip))925 resblks = XFS_DIOSTRAT_SPACE_RES(mp, 0);926 927 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_itruncate, resblks,928 0, 0, &tp);929 if (error)930 return error;931 932 lock_flags |= XFS_ILOCK_EXCL;933 xfs_ilock(ip, XFS_ILOCK_EXCL);934 xfs_trans_ijoin(tp, ip, 0);935 936 /*937 * Only change the c/mtime if we are changing the size or we are938 * explicitly asked to change it. This handles the semantic difference939 * between truncate() and ftruncate() as implemented in the VFS.940 *941 * The regular truncate() case without ATTR_CTIME and ATTR_MTIME is a942 * special case where we need to update the times despite not having943 * these flags set. For all other operations the VFS set these flags944 * explicitly if it wants a timestamp update.945 */946 if (newsize != oldsize &&947 !(iattr->ia_valid & (ATTR_CTIME | ATTR_MTIME))) {948 iattr->ia_ctime = iattr->ia_mtime =949 current_time(inode);950 iattr->ia_valid |= ATTR_CTIME | ATTR_MTIME;951 }952 953 /*954 * The first thing we do is set the size to new_size permanently on955 * disk. This way we don't have to worry about anyone ever being able956 * to look at the data being freed even in the face of a crash.957 * What we're getting around here is the case where we free a block, it958 * is allocated to another file, it is written to, and then we crash.959 * If the new data gets written to the file but the log buffers960 * containing the free and reallocation don't, then we'd end up with961 * garbage in the blocks being freed. As long as we make the new size962 * permanent before actually freeing any blocks it doesn't matter if963 * they get written to.964 */965 ip->i_disk_size = newsize;966 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);967 968 if (newsize <= oldsize) {969 error = xfs_itruncate_extents(&tp, ip, XFS_DATA_FORK, newsize);970 if (error)971 goto out_trans_cancel;972 973 /*974 * Truncated "down", so we're removing references to old data975 * here - if we delay flushing for a long time, we expose976 * ourselves unduly to the notorious NULL files problem. So,977 * we mark this inode and flush it when the file is closed,978 * and do not wait the usual (long) time for writeout.979 */980 xfs_iflags_set(ip, XFS_ITRUNCATED);981 982 /* A truncate down always removes post-EOF blocks. */983 xfs_inode_clear_eofblocks_tag(ip);984 }985 986 ASSERT(!(iattr->ia_valid & (ATTR_UID | ATTR_GID)));987 setattr_copy(idmap, inode, iattr);988 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);989 990 XFS_STATS_INC(mp, xs_ig_attrchg);991 992 if (xfs_has_wsync(mp))993 xfs_trans_set_sync(tp);994 995 error = xfs_trans_commit(tp);996out_unlock:997 if (lock_flags)998 xfs_iunlock(ip, lock_flags);999 return error;1000 1001out_trans_cancel:1002 xfs_trans_cancel(tp);1003 goto out_unlock;1004}1005 1006int1007xfs_vn_setattr_size(1008 struct mnt_idmap *idmap,1009 struct dentry *dentry,1010 struct iattr *iattr)1011{1012 struct xfs_inode *ip = XFS_I(d_inode(dentry));1013 int error;1014 1015 trace_xfs_setattr(ip);1016 1017 error = xfs_vn_change_ok(idmap, dentry, iattr);1018 if (error)1019 return error;1020 return xfs_setattr_size(idmap, dentry, ip, iattr);1021}1022 1023STATIC int1024xfs_vn_setattr(1025 struct mnt_idmap *idmap,1026 struct dentry *dentry,1027 struct iattr *iattr)1028{1029 struct inode *inode = d_inode(dentry);1030 struct xfs_inode *ip = XFS_I(inode);1031 int error;1032 1033 if (iattr->ia_valid & ATTR_SIZE) {1034 uint iolock;1035 1036 xfs_ilock(ip, XFS_MMAPLOCK_EXCL);1037 iolock = XFS_IOLOCK_EXCL | XFS_MMAPLOCK_EXCL;1038 1039 error = xfs_break_layouts(inode, &iolock, BREAK_UNMAP);1040 if (error) {1041 xfs_iunlock(ip, XFS_MMAPLOCK_EXCL);1042 return error;1043 }1044 1045 error = xfs_vn_setattr_size(idmap, dentry, iattr);1046 xfs_iunlock(ip, XFS_MMAPLOCK_EXCL);1047 } else {1048 trace_xfs_setattr(ip);1049 1050 error = xfs_vn_change_ok(idmap, dentry, iattr);1051 if (!error)1052 error = xfs_setattr_nonsize(idmap, dentry, ip, iattr);1053 }1054 1055 return error;1056}1057 1058STATIC int1059xfs_vn_update_time(1060 struct inode *inode,1061 int flags)1062{1063 struct xfs_inode *ip = XFS_I(inode);1064 struct xfs_mount *mp = ip->i_mount;1065 int log_flags = XFS_ILOG_TIMESTAMP;1066 struct xfs_trans *tp;1067 int error;1068 struct timespec64 now;1069 1070 trace_xfs_update_time(ip);1071 1072 if (inode->i_sb->s_flags & SB_LAZYTIME) {1073 if (!((flags & S_VERSION) &&1074 inode_maybe_inc_iversion(inode, false))) {1075 generic_update_time(inode, flags);1076 return 0;1077 }1078 1079 /* Capture the iversion update that just occurred */1080 log_flags |= XFS_ILOG_CORE;1081 }1082 1083 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_fsyncts, 0, 0, 0, &tp);1084 if (error)1085 return error;1086 1087 xfs_ilock(ip, XFS_ILOCK_EXCL);1088 if (flags & (S_CTIME|S_MTIME))1089 now = inode_set_ctime_current(inode);1090 else1091 now = current_time(inode);1092 1093 if (flags & S_MTIME)1094 inode_set_mtime_to_ts(inode, now);1095 if (flags & S_ATIME)1096 inode_set_atime_to_ts(inode, now);1097 1098 xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);1099 xfs_trans_log_inode(tp, ip, log_flags);1100 return xfs_trans_commit(tp);1101}1102 1103STATIC int1104xfs_vn_fiemap(1105 struct inode *inode,1106 struct fiemap_extent_info *fieinfo,1107 u64 start,1108 u64 length)1109{1110 int error;1111 1112 xfs_ilock(XFS_I(inode), XFS_IOLOCK_SHARED);1113 if (fieinfo->fi_flags & FIEMAP_FLAG_XATTR) {1114 fieinfo->fi_flags &= ~FIEMAP_FLAG_XATTR;1115 error = iomap_fiemap(inode, fieinfo, start, length,1116 &xfs_xattr_iomap_ops);1117 } else {1118 error = iomap_fiemap(inode, fieinfo, start, length,1119 &xfs_read_iomap_ops);1120 }1121 xfs_iunlock(XFS_I(inode), XFS_IOLOCK_SHARED);1122 1123 return error;1124}1125 1126STATIC int1127xfs_vn_tmpfile(1128 struct mnt_idmap *idmap,1129 struct inode *dir,1130 struct file *file,1131 umode_t mode)1132{1133 int err = xfs_generic_create(idmap, dir, file->f_path.dentry, mode, 0, file);1134 1135 return finish_open_simple(file, err);1136}1137 1138static const struct inode_operations xfs_inode_operations = {1139 .get_inode_acl = xfs_get_acl,1140 .set_acl = xfs_set_acl,1141 .getattr = xfs_vn_getattr,1142 .setattr = xfs_vn_setattr,1143 .listxattr = xfs_vn_listxattr,1144 .fiemap = xfs_vn_fiemap,1145 .update_time = xfs_vn_update_time,1146 .fileattr_get = xfs_fileattr_get,1147 .fileattr_set = xfs_fileattr_set,1148};1149 1150static const struct inode_operations xfs_dir_inode_operations = {1151 .create = xfs_vn_create,1152 .lookup = xfs_vn_lookup,1153 .link = xfs_vn_link,1154 .unlink = xfs_vn_unlink,1155 .symlink = xfs_vn_symlink,1156 .mkdir = xfs_vn_mkdir,1157 /*1158 * Yes, XFS uses the same method for rmdir and unlink.1159 *1160 * There are some subtile differences deeper in the code,1161 * but we use S_ISDIR to check for those.1162 */1163 .rmdir = xfs_vn_unlink,1164 .mknod = xfs_vn_mknod,1165 .rename = xfs_vn_rename,1166 .get_inode_acl = xfs_get_acl,1167 .set_acl = xfs_set_acl,1168 .getattr = xfs_vn_getattr,1169 .setattr = xfs_vn_setattr,1170 .listxattr = xfs_vn_listxattr,1171 .update_time = xfs_vn_update_time,1172 .tmpfile = xfs_vn_tmpfile,1173 .fileattr_get = xfs_fileattr_get,1174 .fileattr_set = xfs_fileattr_set,1175};1176 1177static const struct inode_operations xfs_dir_ci_inode_operations = {1178 .create = xfs_vn_create,1179 .lookup = xfs_vn_ci_lookup,1180 .link = xfs_vn_link,1181 .unlink = xfs_vn_unlink,1182 .symlink = xfs_vn_symlink,1183 .mkdir = xfs_vn_mkdir,1184 /*1185 * Yes, XFS uses the same method for rmdir and unlink.1186 *1187 * There are some subtile differences deeper in the code,1188 * but we use S_ISDIR to check for those.1189 */1190 .rmdir = xfs_vn_unlink,1191 .mknod = xfs_vn_mknod,1192 .rename = xfs_vn_rename,1193 .get_inode_acl = xfs_get_acl,1194 .set_acl = xfs_set_acl,1195 .getattr = xfs_vn_getattr,1196 .setattr = xfs_vn_setattr,1197 .listxattr = xfs_vn_listxattr,1198 .update_time = xfs_vn_update_time,1199 .tmpfile = xfs_vn_tmpfile,1200 .fileattr_get = xfs_fileattr_get,1201 .fileattr_set = xfs_fileattr_set,1202};1203 1204static const struct inode_operations xfs_symlink_inode_operations = {1205 .get_link = xfs_vn_get_link,1206 .getattr = xfs_vn_getattr,1207 .setattr = xfs_vn_setattr,1208 .listxattr = xfs_vn_listxattr,1209 .update_time = xfs_vn_update_time,1210};1211 1212/* Figure out if this file actually supports DAX. */1213static bool1214xfs_inode_supports_dax(1215 struct xfs_inode *ip)1216{1217 struct xfs_mount *mp = ip->i_mount;1218 1219 /* Only supported on regular files. */1220 if (!S_ISREG(VFS_I(ip)->i_mode))1221 return false;1222 1223 /* Block size must match page size */1224 if (mp->m_sb.sb_blocksize != PAGE_SIZE)1225 return false;1226 1227 /* Device has to support DAX too. */1228 return xfs_inode_buftarg(ip)->bt_daxdev != NULL;1229}1230 1231static bool1232xfs_inode_should_enable_dax(1233 struct xfs_inode *ip)1234{1235 if (!IS_ENABLED(CONFIG_FS_DAX))1236 return false;1237 if (xfs_has_dax_never(ip->i_mount))1238 return false;1239 if (!xfs_inode_supports_dax(ip))1240 return false;1241 if (xfs_has_dax_always(ip->i_mount))1242 return true;1243 if (ip->i_diflags2 & XFS_DIFLAG2_DAX)1244 return true;1245 return false;1246}1247 1248void1249xfs_diflags_to_iflags(1250 struct xfs_inode *ip,1251 bool init)1252{1253 struct inode *inode = VFS_I(ip);1254 unsigned int xflags = xfs_ip2xflags(ip);1255 unsigned int flags = 0;1256 1257 ASSERT(!(IS_DAX(inode) && init));1258 1259 if (xflags & FS_XFLAG_IMMUTABLE)1260 flags |= S_IMMUTABLE;1261 if (xflags & FS_XFLAG_APPEND)1262 flags |= S_APPEND;1263 if (xflags & FS_XFLAG_SYNC)1264 flags |= S_SYNC;1265 if (xflags & FS_XFLAG_NOATIME)1266 flags |= S_NOATIME;1267 if (init && xfs_inode_should_enable_dax(ip))1268 flags |= S_DAX;1269 1270 /*1271 * S_DAX can only be set during inode initialization and is never set by1272 * the VFS, so we cannot mask off S_DAX in i_flags.1273 */1274 inode->i_flags &= ~(S_IMMUTABLE | S_APPEND | S_SYNC | S_NOATIME);1275 inode->i_flags |= flags;1276}1277 1278/*1279 * Initialize the Linux inode.1280 *1281 * When reading existing inodes from disk this is called directly from xfs_iget,1282 * when creating a new inode it is called from xfs_init_new_inode after setting1283 * up the inode. These callers have different criteria for clearing XFS_INEW, so1284 * leave it up to the caller to deal with unlocking the inode appropriately.1285 */1286void1287xfs_setup_inode(1288 struct xfs_inode *ip)1289{1290 struct inode *inode = &ip->i_vnode;1291 gfp_t gfp_mask;1292 1293 inode->i_ino = ip->i_ino;1294 inode->i_state |= I_NEW;1295 1296 inode_sb_list_add(inode);1297 /* make the inode look hashed for the writeback code */1298 inode_fake_hash(inode);1299 1300 i_size_write(inode, ip->i_disk_size);1301 xfs_diflags_to_iflags(ip, true);1302 1303 if (S_ISDIR(inode->i_mode)) {1304 /*1305 * We set the i_rwsem class here to avoid potential races with1306 * lockdep_annotate_inode_mutex_key() reinitialising the lock1307 * after a filehandle lookup has already found the inode in1308 * cache before it has been unlocked via unlock_new_inode().1309 */1310 lockdep_set_class(&inode->i_rwsem,1311 &inode->i_sb->s_type->i_mutex_dir_key);1312 lockdep_set_class(&ip->i_lock, &xfs_dir_ilock_class);1313 } else {1314 lockdep_set_class(&ip->i_lock, &xfs_nondir_ilock_class);1315 }1316 1317 /*1318 * Ensure all page cache allocations are done from GFP_NOFS context to1319 * prevent direct reclaim recursion back into the filesystem and blowing1320 * stacks or deadlocking.1321 */1322 gfp_mask = mapping_gfp_mask(inode->i_mapping);1323 mapping_set_gfp_mask(inode->i_mapping, (gfp_mask & ~(__GFP_FS)));1324 1325 /*1326 * For real-time inodes update the stable write flags to that of the RT1327 * device instead of the data device.1328 */1329 if (S_ISREG(inode->i_mode) && XFS_IS_REALTIME_INODE(ip))1330 xfs_update_stable_writes(ip);1331 1332 /*1333 * If there is no attribute fork no ACL can exist on this inode,1334 * and it can't have any file capabilities attached to it either.1335 */1336 if (!xfs_inode_has_attr_fork(ip)) {1337 inode_has_no_xattr(inode);1338 cache_no_acl(inode);1339 }1340}1341 1342void1343xfs_setup_iops(1344 struct xfs_inode *ip)1345{1346 struct inode *inode = &ip->i_vnode;1347 1348 switch (inode->i_mode & S_IFMT) {1349 case S_IFREG:1350 inode->i_op = &xfs_inode_operations;1351 inode->i_fop = &xfs_file_operations;1352 if (IS_DAX(inode))1353 inode->i_mapping->a_ops = &xfs_dax_aops;1354 else1355 inode->i_mapping->a_ops = &xfs_address_space_operations;1356 break;1357 case S_IFDIR:1358 if (xfs_has_asciici(XFS_M(inode->i_sb)))1359 inode->i_op = &xfs_dir_ci_inode_operations;1360 else1361 inode->i_op = &xfs_dir_inode_operations;1362 inode->i_fop = &xfs_dir_file_operations;1363 break;1364 case S_IFLNK:1365 inode->i_op = &xfs_symlink_inode_operations;1366 break;1367 default:1368 inode->i_op = &xfs_inode_operations;1369 init_special_inode(inode, inode->i_mode, inode->i_rdev);1370 break;1371 }1372}1373