1 // SPDX-License-Identifier: GPL-2.0-only
4 * Copyright (C) 2011 Novell Inc.
8 #include <linux/namei.h>
9 #include <linux/xattr.h>
10 #include <linux/security.h>
11 #include <linux/cred.h>
12 #include <linux/module.h>
13 #include <linux/posix_acl.h>
14 #include <linux/posix_acl_xattr.h>
15 #include <linux/atomic.h>
16 #include <linux/ratelimit.h>
17 #include "overlayfs.h"
19 static unsigned short ovl_redirect_max = 256;
20 module_param_named(redirect_max, ovl_redirect_max, ushort, 0644);
21 MODULE_PARM_DESC(redirect_max,
22 "Maximum length of absolute redirect xattr value");
24 static int ovl_set_redirect(struct dentry *dentry, bool samedir);
26 int ovl_cleanup(struct inode *wdir, struct dentry *wdentry)
31 if (d_is_dir(wdentry))
32 err = ovl_do_rmdir(wdir, wdentry);
34 err = ovl_do_unlink(wdir, wdentry);
38 pr_err("overlayfs: cleanup of '%pd2' failed (%i)\n",
45 static struct dentry *ovl_lookup_temp(struct dentry *workdir)
49 static atomic_t temp_id = ATOMIC_INIT(0);
51 /* counter is allowed to wrap, since temp dentries are ephemeral */
52 snprintf(name, sizeof(name), "#%x", atomic_inc_return(&temp_id));
54 temp = lookup_one_len(name, workdir, strlen(name));
55 if (!IS_ERR(temp) && temp->d_inode) {
56 pr_err("overlayfs: workdir/%s already exists\n", name);
64 /* caller holds i_mutex on workdir */
65 static struct dentry *ovl_whiteout(struct dentry *workdir)
68 struct dentry *whiteout;
69 struct inode *wdir = workdir->d_inode;
71 whiteout = ovl_lookup_temp(workdir);
75 err = ovl_do_whiteout(wdir, whiteout);
78 whiteout = ERR_PTR(err);
84 /* Caller must hold i_mutex on both workdir and dir */
85 int ovl_cleanup_and_whiteout(struct dentry *workdir, struct inode *dir,
86 struct dentry *dentry)
88 struct inode *wdir = workdir->d_inode;
89 struct dentry *whiteout;
93 whiteout = ovl_whiteout(workdir);
94 err = PTR_ERR(whiteout);
99 flags = RENAME_EXCHANGE;
101 err = ovl_do_rename(wdir, whiteout, dir, dentry, flags);
105 ovl_cleanup(wdir, dentry);
112 ovl_cleanup(wdir, whiteout);
116 int ovl_mkdir_real(struct inode *dir, struct dentry **newdentry, umode_t mode)
119 struct dentry *d, *dentry = *newdentry;
121 err = ovl_do_mkdir(dir, dentry, mode);
125 if (likely(!d_unhashed(dentry)))
129 * vfs_mkdir() may succeed and leave the dentry passed
130 * to it unhashed and negative. If that happens, try to
131 * lookup a new hashed and positive dentry.
133 d = lookup_one_len(dentry->d_name.name, dentry->d_parent,
136 pr_warn("overlayfs: failed lookup after mkdir (%pd2, err=%i).\n",
146 struct dentry *ovl_create_real(struct inode *dir, struct dentry *newdentry,
147 struct ovl_cattr *attr)
151 if (IS_ERR(newdentry))
155 if (newdentry->d_inode)
158 if (attr->hardlink) {
159 err = ovl_do_link(attr->hardlink, dir, newdentry);
161 switch (attr->mode & S_IFMT) {
163 err = ovl_do_create(dir, newdentry, attr->mode);
167 /* mkdir is special... */
168 err = ovl_mkdir_real(dir, &newdentry, attr->mode);
175 err = ovl_do_mknod(dir, newdentry, attr->mode,
180 err = ovl_do_symlink(dir, newdentry, attr->link);
187 if (!err && WARN_ON(!newdentry->d_inode)) {
189 * Not quite sure if non-instantiated dentry is legal or not.
190 * VFS doesn't seem to care so check and warn here.
202 struct dentry *ovl_create_temp(struct dentry *workdir, struct ovl_cattr *attr)
204 return ovl_create_real(d_inode(workdir), ovl_lookup_temp(workdir),
208 static int ovl_set_opaque_xerr(struct dentry *dentry, struct dentry *upper,
213 err = ovl_check_setxattr(dentry, upper, OVL_XATTR_OPAQUE, "y", 1, xerr);
215 ovl_dentry_set_opaque(dentry);
220 static int ovl_set_opaque(struct dentry *dentry, struct dentry *upperdentry)
223 * Fail with -EIO when trying to create opaque dir and upper doesn't
224 * support xattrs. ovl_rename() calls ovl_set_opaque_xerr(-EXDEV) to
225 * return a specific error for noxattr case.
227 return ovl_set_opaque_xerr(dentry, upperdentry, -EIO);
231 * Common operations required to be done after creation of file on upper.
232 * If @hardlink is false, then @inode is a pre-allocated inode, we may or
233 * may not use to instantiate the new dentry.
235 static int ovl_instantiate(struct dentry *dentry, struct inode *inode,
236 struct dentry *newdentry, bool hardlink)
238 struct ovl_inode_params oip = {
239 .upperdentry = newdentry,
243 ovl_dir_modified(dentry->d_parent, false);
244 ovl_dentry_set_upper_alias(dentry);
247 * ovl_obtain_alias() can be called after ovl_create_real()
248 * and before we get here, so we may get an inode from cache
249 * with the same real upperdentry that is not the inode we
250 * pre-allocated. In this case we will use the cached inode
251 * to instantiate the new dentry.
253 * XXX: if we ever use ovl_obtain_alias() to decode directory
254 * file handles, need to use ovl_get_inode_locked() and
255 * d_instantiate_new() here to prevent from creating two
256 * hashed directory inode aliases.
258 inode = ovl_get_inode(dentry->d_sb, &oip);
260 return PTR_ERR(inode);
262 WARN_ON(ovl_inode_real(inode) != d_inode(newdentry));
267 d_instantiate(dentry, inode);
268 if (inode != oip.newinode) {
269 pr_warn_ratelimited("overlayfs: newly created inode found in cache (%pd2)\n",
273 /* Force lookup of new upper hardlink to find its lower */
280 static bool ovl_type_merge(struct dentry *dentry)
282 return OVL_TYPE_MERGE(ovl_path_type(dentry));
285 static bool ovl_type_origin(struct dentry *dentry)
287 return OVL_TYPE_ORIGIN(ovl_path_type(dentry));
290 static int ovl_create_upper(struct dentry *dentry, struct inode *inode,
291 struct ovl_cattr *attr)
293 struct dentry *upperdir = ovl_dentry_upper(dentry->d_parent);
294 struct inode *udir = upperdir->d_inode;
295 struct dentry *newdentry;
298 if (!attr->hardlink && !IS_POSIXACL(udir))
299 attr->mode &= ~current_umask();
301 inode_lock_nested(udir, I_MUTEX_PARENT);
302 newdentry = ovl_create_real(udir,
303 lookup_one_len(dentry->d_name.name,
307 err = PTR_ERR(newdentry);
308 if (IS_ERR(newdentry))
311 if (ovl_type_merge(dentry->d_parent) && d_is_dir(newdentry)) {
312 /* Setting opaque here is just an optimization, allow to fail */
313 ovl_set_opaque(dentry, newdentry);
316 err = ovl_instantiate(dentry, inode, newdentry, !!attr->hardlink);
324 ovl_cleanup(udir, newdentry);
329 static struct dentry *ovl_clear_empty(struct dentry *dentry,
330 struct list_head *list)
332 struct dentry *workdir = ovl_workdir(dentry);
333 struct inode *wdir = workdir->d_inode;
334 struct dentry *upperdir = ovl_dentry_upper(dentry->d_parent);
335 struct inode *udir = upperdir->d_inode;
336 struct path upperpath;
337 struct dentry *upper;
338 struct dentry *opaquedir;
342 if (WARN_ON(!workdir))
343 return ERR_PTR(-EROFS);
345 err = ovl_lock_rename_workdir(workdir, upperdir);
349 ovl_path_upper(dentry, &upperpath);
350 err = vfs_getattr(&upperpath, &stat,
351 STATX_BASIC_STATS, AT_STATX_SYNC_AS_STAT);
356 if (!S_ISDIR(stat.mode))
358 upper = upperpath.dentry;
359 if (upper->d_parent->d_inode != udir)
362 opaquedir = ovl_create_temp(workdir, OVL_CATTR(stat.mode));
363 err = PTR_ERR(opaquedir);
364 if (IS_ERR(opaquedir))
367 err = ovl_copy_xattr(upper, opaquedir);
371 err = ovl_set_opaque(dentry, opaquedir);
375 inode_lock(opaquedir->d_inode);
376 err = ovl_set_attr(opaquedir, &stat);
377 inode_unlock(opaquedir->d_inode);
381 err = ovl_do_rename(wdir, opaquedir, udir, upper, RENAME_EXCHANGE);
385 ovl_cleanup_whiteouts(upper, list);
386 ovl_cleanup(wdir, upper);
387 unlock_rename(workdir, upperdir);
389 /* dentry's upper doesn't match now, get rid of it */
395 ovl_cleanup(wdir, opaquedir);
398 unlock_rename(workdir, upperdir);
403 static int ovl_set_upper_acl(struct dentry *upperdentry, const char *name,
404 const struct posix_acl *acl)
410 if (!IS_ENABLED(CONFIG_FS_POSIX_ACL) || !acl)
413 size = posix_acl_xattr_size(acl->a_count);
414 buffer = kmalloc(size, GFP_KERNEL);
418 err = posix_acl_to_xattr(&init_user_ns, acl, buffer, size);
422 err = vfs_setxattr(upperdentry, name, buffer, size, XATTR_CREATE);
428 static int ovl_create_over_whiteout(struct dentry *dentry, struct inode *inode,
429 struct ovl_cattr *cattr)
431 struct dentry *workdir = ovl_workdir(dentry);
432 struct inode *wdir = workdir->d_inode;
433 struct dentry *upperdir = ovl_dentry_upper(dentry->d_parent);
434 struct inode *udir = upperdir->d_inode;
435 struct dentry *upper;
436 struct dentry *newdentry;
438 struct posix_acl *acl, *default_acl;
439 bool hardlink = !!cattr->hardlink;
441 if (WARN_ON(!workdir))
445 err = posix_acl_create(dentry->d_parent->d_inode,
446 &cattr->mode, &default_acl, &acl);
451 err = ovl_lock_rename_workdir(workdir, upperdir);
455 upper = lookup_one_len(dentry->d_name.name, upperdir,
457 err = PTR_ERR(upper);
462 if (d_is_negative(upper) || !IS_WHITEOUT(d_inode(upper)))
465 newdentry = ovl_create_temp(workdir, cattr);
466 err = PTR_ERR(newdentry);
467 if (IS_ERR(newdentry))
471 * mode could have been mutilated due to umask (e.g. sgid directory)
474 !S_ISLNK(cattr->mode) &&
475 newdentry->d_inode->i_mode != cattr->mode) {
476 struct iattr attr = {
477 .ia_valid = ATTR_MODE,
478 .ia_mode = cattr->mode,
480 inode_lock(newdentry->d_inode);
481 err = notify_change(newdentry, &attr, NULL);
482 inode_unlock(newdentry->d_inode);
487 err = ovl_set_upper_acl(newdentry, XATTR_NAME_POSIX_ACL_ACCESS,
492 err = ovl_set_upper_acl(newdentry, XATTR_NAME_POSIX_ACL_DEFAULT,
498 if (!hardlink && S_ISDIR(cattr->mode)) {
499 err = ovl_set_opaque(dentry, newdentry);
503 err = ovl_do_rename(wdir, newdentry, udir, upper,
508 ovl_cleanup(wdir, upper);
510 err = ovl_do_rename(wdir, newdentry, udir, upper, 0);
514 err = ovl_instantiate(dentry, inode, newdentry, hardlink);
516 ovl_cleanup(udir, newdentry);
522 unlock_rename(workdir, upperdir);
525 posix_acl_release(acl);
526 posix_acl_release(default_acl);
531 ovl_cleanup(wdir, newdentry);
536 static int ovl_create_or_link(struct dentry *dentry, struct inode *inode,
537 struct ovl_cattr *attr, bool origin)
540 const struct cred *old_cred;
541 struct cred *override_cred;
542 struct dentry *parent = dentry->d_parent;
544 err = ovl_copy_up(parent);
548 old_cred = ovl_override_creds(dentry->d_sb);
551 * When linking a file with copy up origin into a new parent, mark the
552 * new parent dir "impure".
555 err = ovl_set_impure(parent, ovl_dentry_upper(parent));
557 goto out_revert_creds;
560 if (!attr->hardlink) {
562 override_cred = prepare_creds();
564 goto out_revert_creds;
566 * In the creation cases(create, mkdir, mknod, symlink),
567 * ovl should transfer current's fs{u,g}id to underlying
568 * fs. Because underlying fs want to initialize its new
569 * inode owner using current's fs{u,g}id. And in this
570 * case, the @inode is a new inode that is initialized
571 * in inode_init_owner() to current's fs{u,g}id. So use
572 * the inode's i_{u,g}id to override the cred's fs{u,g}id.
574 * But in the other hardlink case, ovl_link() does not
575 * create a new inode, so just use the ovl mounter's
578 override_cred->fsuid = inode->i_uid;
579 override_cred->fsgid = inode->i_gid;
580 err = security_dentry_create_files_as(dentry,
581 attr->mode, &dentry->d_name, old_cred,
584 put_cred(override_cred);
585 goto out_revert_creds;
587 put_cred(override_creds(override_cred));
588 put_cred(override_cred);
591 if (!ovl_dentry_is_whiteout(dentry))
592 err = ovl_create_upper(dentry, inode, attr);
594 err = ovl_create_over_whiteout(dentry, inode, attr);
597 revert_creds(old_cred);
601 static int ovl_create_object(struct dentry *dentry, int mode, dev_t rdev,
606 struct ovl_cattr attr = {
611 err = ovl_want_write(dentry);
615 /* Preallocate inode to be used by ovl_get_inode() */
617 inode = ovl_new_inode(dentry->d_sb, mode, rdev);
621 spin_lock(&inode->i_lock);
622 inode->i_state |= I_CREATING;
623 spin_unlock(&inode->i_lock);
625 inode_init_owner(inode, dentry->d_parent->d_inode, mode);
626 attr.mode = inode->i_mode;
628 err = ovl_create_or_link(dentry, inode, &attr, false);
629 /* Did we end up using the preallocated inode? */
630 if (inode != d_inode(dentry))
634 ovl_drop_write(dentry);
639 static int ovl_create(struct inode *dir, struct dentry *dentry, umode_t mode,
642 return ovl_create_object(dentry, (mode & 07777) | S_IFREG, 0, NULL);
645 static int ovl_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
647 return ovl_create_object(dentry, (mode & 07777) | S_IFDIR, 0, NULL);
650 static int ovl_mknod(struct inode *dir, struct dentry *dentry, umode_t mode,
653 /* Don't allow creation of "whiteout" on overlay */
654 if (S_ISCHR(mode) && rdev == WHITEOUT_DEV)
657 return ovl_create_object(dentry, mode, rdev, NULL);
660 static int ovl_symlink(struct inode *dir, struct dentry *dentry,
663 return ovl_create_object(dentry, S_IFLNK, 0, link);
666 static int ovl_set_link_redirect(struct dentry *dentry)
668 const struct cred *old_cred;
671 old_cred = ovl_override_creds(dentry->d_sb);
672 err = ovl_set_redirect(dentry, false);
673 revert_creds(old_cred);
678 static int ovl_link(struct dentry *old, struct inode *newdir,
684 err = ovl_want_write(old);
688 err = ovl_copy_up(old);
692 err = ovl_copy_up(new->d_parent);
696 if (ovl_is_metacopy_dentry(old)) {
697 err = ovl_set_link_redirect(old);
702 err = ovl_nlink_start(old);
706 inode = d_inode(old);
709 err = ovl_create_or_link(new, inode,
710 &(struct ovl_cattr) {.hardlink = ovl_dentry_upper(old)},
711 ovl_type_origin(old));
722 static bool ovl_matches_upper(struct dentry *dentry, struct dentry *upper)
724 return d_inode(ovl_dentry_upper(dentry)) == d_inode(upper);
727 static int ovl_remove_and_whiteout(struct dentry *dentry,
728 struct list_head *list)
730 struct dentry *workdir = ovl_workdir(dentry);
731 struct dentry *upperdir = ovl_dentry_upper(dentry->d_parent);
732 struct dentry *upper;
733 struct dentry *opaquedir = NULL;
736 if (WARN_ON(!workdir))
739 if (!list_empty(list)) {
740 opaquedir = ovl_clear_empty(dentry, list);
741 err = PTR_ERR(opaquedir);
742 if (IS_ERR(opaquedir))
746 err = ovl_lock_rename_workdir(workdir, upperdir);
750 upper = lookup_one_len(dentry->d_name.name, upperdir,
752 err = PTR_ERR(upper);
757 if ((opaquedir && upper != opaquedir) ||
758 (!opaquedir && ovl_dentry_upper(dentry) &&
759 !ovl_matches_upper(dentry, upper))) {
763 err = ovl_cleanup_and_whiteout(workdir, d_inode(upperdir), upper);
767 ovl_dir_modified(dentry->d_parent, true);
773 unlock_rename(workdir, upperdir);
780 static int ovl_remove_upper(struct dentry *dentry, bool is_dir,
781 struct list_head *list)
783 struct dentry *upperdir = ovl_dentry_upper(dentry->d_parent);
784 struct inode *dir = upperdir->d_inode;
785 struct dentry *upper;
786 struct dentry *opaquedir = NULL;
789 if (!list_empty(list)) {
790 opaquedir = ovl_clear_empty(dentry, list);
791 err = PTR_ERR(opaquedir);
792 if (IS_ERR(opaquedir))
796 inode_lock_nested(dir, I_MUTEX_PARENT);
797 upper = lookup_one_len(dentry->d_name.name, upperdir,
799 err = PTR_ERR(upper);
804 if ((opaquedir && upper != opaquedir) ||
805 (!opaquedir && !ovl_matches_upper(dentry, upper)))
809 err = vfs_rmdir(dir, upper);
811 err = vfs_unlink(dir, upper, NULL);
812 ovl_dir_modified(dentry->d_parent, ovl_type_origin(dentry));
815 * Keeping this dentry hashed would mean having to release
816 * upperpath/lowerpath, which could only be done if we are the
817 * sole user of this dentry. Too tricky... Just unhash for
831 static bool ovl_pure_upper(struct dentry *dentry)
833 return !ovl_dentry_lower(dentry) &&
834 !ovl_test_flag(OVL_WHITEOUTS, d_inode(dentry));
837 static int ovl_do_remove(struct dentry *dentry, bool is_dir)
840 const struct cred *old_cred;
841 struct dentry *upperdentry;
842 bool lower_positive = ovl_lower_positive(dentry);
845 /* No need to clean pure upper removed by vfs_rmdir() */
846 if (is_dir && (lower_positive || !ovl_pure_upper(dentry))) {
847 err = ovl_check_empty_dir(dentry, &list);
852 err = ovl_want_write(dentry);
856 err = ovl_copy_up(dentry->d_parent);
860 err = ovl_nlink_start(dentry);
864 old_cred = ovl_override_creds(dentry->d_sb);
866 err = ovl_remove_upper(dentry, is_dir, &list);
868 err = ovl_remove_and_whiteout(dentry, &list);
869 revert_creds(old_cred);
872 clear_nlink(dentry->d_inode);
874 drop_nlink(dentry->d_inode);
876 ovl_nlink_end(dentry);
881 * Note: we fail to update ctime if there was no copy-up, only a
884 upperdentry = ovl_dentry_upper(dentry);
886 ovl_copyattr(d_inode(upperdentry), d_inode(dentry));
889 ovl_drop_write(dentry);
891 ovl_cache_free(&list);
895 static int ovl_unlink(struct inode *dir, struct dentry *dentry)
897 return ovl_do_remove(dentry, false);
900 static int ovl_rmdir(struct inode *dir, struct dentry *dentry)
902 return ovl_do_remove(dentry, true);
905 static bool ovl_type_merge_or_lower(struct dentry *dentry)
907 enum ovl_path_type type = ovl_path_type(dentry);
909 return OVL_TYPE_MERGE(type) || !OVL_TYPE_UPPER(type);
912 static bool ovl_can_move(struct dentry *dentry)
914 return ovl_redirect_dir(dentry->d_sb) ||
915 !d_is_dir(dentry) || !ovl_type_merge_or_lower(dentry);
918 static char *ovl_get_redirect(struct dentry *dentry, bool abs_redirect)
921 struct dentry *d, *tmp;
922 int buflen = ovl_redirect_max + 1;
925 ret = kstrndup(dentry->d_name.name, dentry->d_name.len,
930 buf = ret = kmalloc(buflen, GFP_KERNEL);
936 for (d = dget(dentry); !IS_ROOT(d);) {
940 spin_lock(&d->d_lock);
941 name = ovl_dentry_get_redirect(d);
943 thislen = strlen(name);
945 name = d->d_name.name;
946 thislen = d->d_name.len;
949 /* If path is too long, fall back to userspace move */
950 if (thislen + (name[0] != '/') > buflen) {
951 ret = ERR_PTR(-EXDEV);
952 spin_unlock(&d->d_lock);
957 memcpy(&buf[buflen], name, thislen);
958 spin_unlock(&d->d_lock);
959 tmp = dget_parent(d);
964 /* Absolute redirect: finished */
965 if (buf[buflen] == '/')
970 ret = kstrdup(&buf[buflen], GFP_KERNEL);
975 return ret ? ret : ERR_PTR(-ENOMEM);
978 static bool ovl_need_absolute_redirect(struct dentry *dentry, bool samedir)
980 struct dentry *lowerdentry;
985 if (d_is_dir(dentry))
989 * For non-dir hardlinked files, we need absolute redirects
990 * in general as two upper hardlinks could be in different
991 * dirs. We could put a relative redirect now and convert
992 * it to absolute redirect later. But when nlink > 1 and
993 * indexing is on, that means relative redirect needs to be
994 * converted to absolute during copy up of another lower
997 * So without optimizing too much, just check if lower is
998 * a hard link or not. If lower is hard link, put absolute
1001 lowerdentry = ovl_dentry_lower(dentry);
1002 return (d_inode(lowerdentry)->i_nlink > 1);
1005 static int ovl_set_redirect(struct dentry *dentry, bool samedir)
1008 const char *redirect = ovl_dentry_get_redirect(dentry);
1009 bool absolute_redirect = ovl_need_absolute_redirect(dentry, samedir);
1011 if (redirect && (!absolute_redirect || redirect[0] == '/'))
1014 redirect = ovl_get_redirect(dentry, absolute_redirect);
1015 if (IS_ERR(redirect))
1016 return PTR_ERR(redirect);
1018 err = ovl_check_setxattr(dentry, ovl_dentry_upper(dentry),
1020 redirect, strlen(redirect), -EXDEV);
1022 spin_lock(&dentry->d_lock);
1023 ovl_dentry_set_redirect(dentry, redirect);
1024 spin_unlock(&dentry->d_lock);
1027 pr_warn_ratelimited("overlayfs: failed to set redirect (%i)\n",
1029 /* Fall back to userspace copy-up */
1035 static int ovl_rename(struct inode *olddir, struct dentry *old,
1036 struct inode *newdir, struct dentry *new,
1040 struct dentry *old_upperdir;
1041 struct dentry *new_upperdir;
1042 struct dentry *olddentry;
1043 struct dentry *newdentry;
1044 struct dentry *trap;
1047 bool cleanup_whiteout = false;
1048 bool update_nlink = false;
1049 bool overwrite = !(flags & RENAME_EXCHANGE);
1050 bool is_dir = d_is_dir(old);
1051 bool new_is_dir = d_is_dir(new);
1052 bool samedir = olddir == newdir;
1053 struct dentry *opaquedir = NULL;
1054 const struct cred *old_cred = NULL;
1058 if (flags & ~(RENAME_EXCHANGE | RENAME_NOREPLACE))
1061 flags &= ~RENAME_NOREPLACE;
1063 /* Don't copy up directory trees */
1065 if (!ovl_can_move(old))
1067 if (!overwrite && !ovl_can_move(new))
1070 if (overwrite && new_is_dir && !ovl_pure_upper(new)) {
1071 err = ovl_check_empty_dir(new, &list);
1077 if (ovl_lower_positive(old)) {
1078 if (!ovl_dentry_is_whiteout(new)) {
1079 /* Whiteout source */
1080 flags |= RENAME_WHITEOUT;
1082 /* Switch whiteouts */
1083 flags |= RENAME_EXCHANGE;
1085 } else if (is_dir && ovl_dentry_is_whiteout(new)) {
1086 flags |= RENAME_EXCHANGE;
1087 cleanup_whiteout = true;
1091 err = ovl_want_write(old);
1095 err = ovl_copy_up(old);
1097 goto out_drop_write;
1099 err = ovl_copy_up(new->d_parent);
1101 goto out_drop_write;
1103 err = ovl_copy_up(new);
1105 goto out_drop_write;
1106 } else if (d_inode(new)) {
1107 err = ovl_nlink_start(new);
1109 goto out_drop_write;
1111 update_nlink = true;
1114 old_cred = ovl_override_creds(old->d_sb);
1116 if (!list_empty(&list)) {
1117 opaquedir = ovl_clear_empty(new, &list);
1118 err = PTR_ERR(opaquedir);
1119 if (IS_ERR(opaquedir)) {
1121 goto out_revert_creds;
1125 old_upperdir = ovl_dentry_upper(old->d_parent);
1126 new_upperdir = ovl_dentry_upper(new->d_parent);
1130 * When moving a merge dir or non-dir with copy up origin into
1131 * a new parent, we are marking the new parent dir "impure".
1132 * When ovl_iterate() iterates an "impure" upper dir, it will
1133 * lookup the origin inodes of the entries to fill d_ino.
1135 if (ovl_type_origin(old)) {
1136 err = ovl_set_impure(new->d_parent, new_upperdir);
1138 goto out_revert_creds;
1140 if (!overwrite && ovl_type_origin(new)) {
1141 err = ovl_set_impure(old->d_parent, old_upperdir);
1143 goto out_revert_creds;
1147 trap = lock_rename(new_upperdir, old_upperdir);
1149 olddentry = lookup_one_len(old->d_name.name, old_upperdir,
1151 err = PTR_ERR(olddentry);
1152 if (IS_ERR(olddentry))
1156 if (!ovl_matches_upper(old, olddentry))
1159 newdentry = lookup_one_len(new->d_name.name, new_upperdir,
1161 err = PTR_ERR(newdentry);
1162 if (IS_ERR(newdentry))
1165 old_opaque = ovl_dentry_is_opaque(old);
1166 new_opaque = ovl_dentry_is_opaque(new);
1169 if (d_inode(new) && ovl_dentry_upper(new)) {
1171 if (newdentry != opaquedir)
1174 if (!ovl_matches_upper(new, newdentry))
1178 if (!d_is_negative(newdentry)) {
1179 if (!new_opaque || !ovl_is_whiteout(newdentry))
1182 if (flags & RENAME_EXCHANGE)
1187 if (olddentry == trap)
1189 if (newdentry == trap)
1192 if (olddentry->d_inode == newdentry->d_inode)
1196 if (ovl_type_merge_or_lower(old))
1197 err = ovl_set_redirect(old, samedir);
1198 else if (is_dir && !old_opaque && ovl_type_merge(new->d_parent))
1199 err = ovl_set_opaque_xerr(old, olddentry, -EXDEV);
1203 if (!overwrite && ovl_type_merge_or_lower(new))
1204 err = ovl_set_redirect(new, samedir);
1205 else if (!overwrite && new_is_dir && !new_opaque &&
1206 ovl_type_merge(old->d_parent))
1207 err = ovl_set_opaque_xerr(new, newdentry, -EXDEV);
1211 err = ovl_do_rename(old_upperdir->d_inode, olddentry,
1212 new_upperdir->d_inode, newdentry, flags);
1216 if (cleanup_whiteout)
1217 ovl_cleanup(old_upperdir->d_inode, newdentry);
1219 if (overwrite && d_inode(new)) {
1221 clear_nlink(d_inode(new));
1223 drop_nlink(d_inode(new));
1226 ovl_dir_modified(old->d_parent, ovl_type_origin(old) ||
1227 (!overwrite && ovl_type_origin(new)));
1228 ovl_dir_modified(new->d_parent, ovl_type_origin(old) ||
1229 (d_inode(new) && ovl_type_origin(new)));
1232 ovl_copyattr(d_inode(olddentry), d_inode(old));
1233 if (d_inode(new) && ovl_dentry_upper(new))
1234 ovl_copyattr(d_inode(newdentry), d_inode(new));
1241 unlock_rename(new_upperdir, old_upperdir);
1243 revert_creds(old_cred);
1247 ovl_drop_write(old);
1250 ovl_cache_free(&list);
1254 const struct inode_operations ovl_dir_inode_operations = {
1255 .lookup = ovl_lookup,
1257 .symlink = ovl_symlink,
1258 .unlink = ovl_unlink,
1260 .rename = ovl_rename,
1262 .setattr = ovl_setattr,
1263 .create = ovl_create,
1265 .permission = ovl_permission,
1266 .getattr = ovl_getattr,
1267 .listxattr = ovl_listxattr,
1268 .get_acl = ovl_get_acl,
1269 .update_time = ovl_update_time,