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authorLinus Torvalds <torvalds@linux-foundation.org>2014-04-04 14:03:05 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2014-04-04 14:03:05 -0700
commit7df934526c0b3775613502dcd19ab6d2da8cce1e (patch)
tree01e6a4ea20c676228f4acefc6ae776d2e52072db /fs
parent3c83e61e67256e0bb08c46cc2db43b58fd617251 (diff)
parentbd42998a6bcb9b1708dac9ca9876e3d304c16f3d (diff)
Merge branch 'cross-rename' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs
Pull renameat2 system call from Miklos Szeredi: "This adds a new syscall, renameat2(), which is the same as renameat() but with a flags argument. The purpose of extending rename is to add cross-rename, a symmetric variant of rename, which exchanges the two files. This allows interesting things, which were not possible before, for example atomically replacing a directory tree with a symlink, etc... This also allows overlayfs and friends to operate on whiteouts atomically. Andy Lutomirski also suggested a "noreplace" flag, which disables the overwriting behavior of rename. These two flags, RENAME_EXCHANGE and RENAME_NOREPLACE are only implemented for ext4 as an example and for testing" * 'cross-rename' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs: ext4: add cross rename support ext4: rename: split out helper functions ext4: rename: move EMLINK check up ext4: rename: create ext4_renament structure for local vars vfs: add cross-rename vfs: lock_two_nondirectories: allow directory args security: add flags to rename hooks vfs: add RENAME_NOREPLACE flag vfs: add renameat2 syscall vfs: rename: use common code for dir and non-dir vfs: rename: move d_move() up vfs: add d_is_dir()
Diffstat (limited to 'fs')
-rw-r--r--fs/cachefiles/namei.c4
-rw-r--r--fs/dcache.c50
-rw-r--r--fs/ecryptfs/inode.c2
-rw-r--r--fs/ext4/namei.c480
-rw-r--r--fs/inode.c25
-rw-r--r--fs/namei.c315
-rw-r--r--fs/nfsd/vfs.c2
7 files changed, 577 insertions, 301 deletions
diff --git a/fs/cachefiles/namei.c b/fs/cachefiles/namei.c
index ca65f39dc8dc..6494d9f673aa 100644
--- a/fs/cachefiles/namei.c
+++ b/fs/cachefiles/namei.c
@@ -391,12 +391,12 @@ try_again:
path.dentry = dir;
path_to_graveyard.mnt = cache->mnt;
path_to_graveyard.dentry = cache->graveyard;
- ret = security_path_rename(&path, rep, &path_to_graveyard, grave);
+ ret = security_path_rename(&path, rep, &path_to_graveyard, grave, 0);
if (ret < 0) {
cachefiles_io_error(cache, "Rename security error %d", ret);
} else {
ret = vfs_rename(dir->d_inode, rep,
- cache->graveyard->d_inode, grave, NULL);
+ cache->graveyard->d_inode, grave, NULL, 0);
if (ret != 0 && ret != -ENOMEM)
cachefiles_io_error(cache,
"Rename failed with error %d", ret);
diff --git a/fs/dcache.c b/fs/dcache.c
index ca02c13a84aa..66cba5a8a346 100644
--- a/fs/dcache.c
+++ b/fs/dcache.c
@@ -2483,12 +2483,14 @@ static void switch_names(struct dentry *dentry, struct dentry *target)
dentry->d_name.name = dentry->d_iname;
} else {
/*
- * Both are internal. Just copy target to dentry
+ * Both are internal.
*/
- memcpy(dentry->d_iname, target->d_name.name,
- target->d_name.len + 1);
- dentry->d_name.len = target->d_name.len;
- return;
+ unsigned int i;
+ BUILD_BUG_ON(!IS_ALIGNED(DNAME_INLINE_LEN, sizeof(long)));
+ for (i = 0; i < DNAME_INLINE_LEN / sizeof(long); i++) {
+ swap(((long *) &dentry->d_iname)[i],
+ ((long *) &target->d_iname)[i]);
+ }
}
}
swap(dentry->d_name.len, target->d_name.len);
@@ -2545,13 +2547,15 @@ static void dentry_unlock_parents_for_move(struct dentry *dentry,
* __d_move - move a dentry
* @dentry: entry to move
* @target: new dentry
+ * @exchange: exchange the two dentries
*
* Update the dcache to reflect the move of a file name. Negative
* dcache entries should not be moved in this way. Caller must hold
* rename_lock, the i_mutex of the source and target directories,
* and the sb->s_vfs_rename_mutex if they differ. See lock_rename().
*/
-static void __d_move(struct dentry * dentry, struct dentry * target)
+static void __d_move(struct dentry *dentry, struct dentry *target,
+ bool exchange)
{
if (!dentry->d_inode)
printk(KERN_WARNING "VFS: moving negative dcache entry\n");
@@ -2573,8 +2577,15 @@ static void __d_move(struct dentry * dentry, struct dentry * target)
__d_drop(dentry);
__d_rehash(dentry, d_hash(target->d_parent, target->d_name.hash));
- /* Unhash the target: dput() will then get rid of it */
+ /*
+ * Unhash the target (d_delete() is not usable here). If exchanging
+ * the two dentries, then rehash onto the other's hash queue.
+ */
__d_drop(target);
+ if (exchange) {
+ __d_rehash(target,
+ d_hash(dentry->d_parent, dentry->d_name.hash));
+ }
list_del(&dentry->d_u.d_child);
list_del(&target->d_u.d_child);
@@ -2601,6 +2612,8 @@ static void __d_move(struct dentry * dentry, struct dentry * target)
write_seqcount_end(&dentry->d_seq);
dentry_unlock_parents_for_move(dentry, target);
+ if (exchange)
+ fsnotify_d_move(target);
spin_unlock(&target->d_lock);
fsnotify_d_move(dentry);
spin_unlock(&dentry->d_lock);
@@ -2618,11 +2631,30 @@ static void __d_move(struct dentry * dentry, struct dentry * target)
void d_move(struct dentry *dentry, struct dentry *target)
{
write_seqlock(&rename_lock);
- __d_move(dentry, target);
+ __d_move(dentry, target, false);
write_sequnlock(&rename_lock);
}
EXPORT_SYMBOL(d_move);
+/*
+ * d_exchange - exchange two dentries
+ * @dentry1: first dentry
+ * @dentry2: second dentry
+ */
+void d_exchange(struct dentry *dentry1, struct dentry *dentry2)
+{
+ write_seqlock(&rename_lock);
+
+ WARN_ON(!dentry1->d_inode);
+ WARN_ON(!dentry2->d_inode);
+ WARN_ON(IS_ROOT(dentry1));
+ WARN_ON(IS_ROOT(dentry2));
+
+ __d_move(dentry1, dentry2, true);
+
+ write_sequnlock(&rename_lock);
+}
+
/**
* d_ancestor - search for an ancestor
* @p1: ancestor dentry
@@ -2670,7 +2702,7 @@ static struct dentry *__d_unalias(struct inode *inode,
m2 = &alias->d_parent->d_inode->i_mutex;
out_unalias:
if (likely(!d_mountpoint(alias))) {
- __d_move(alias, dentry);
+ __d_move(alias, dentry, false);
ret = alias;
}
out_err:
diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c
index b167ca48b8ee..d4a9431ec73c 100644
--- a/fs/ecryptfs/inode.c
+++ b/fs/ecryptfs/inode.c
@@ -641,7 +641,7 @@ ecryptfs_rename(struct inode *old_dir, struct dentry *old_dentry,
}
rc = vfs_rename(lower_old_dir_dentry->d_inode, lower_old_dentry,
lower_new_dir_dentry->d_inode, lower_new_dentry,
- NULL);
+ NULL, 0);
if (rc)
goto out_lock;
if (target_inode)
diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
index d050e043e884..1cb84f78909e 100644
--- a/fs/ext4/namei.c
+++ b/fs/ext4/namei.c
@@ -3000,6 +3000,154 @@ static struct buffer_head *ext4_get_first_dir_block(handle_t *handle,
return ext4_get_first_inline_block(inode, parent_de, retval);
}
+struct ext4_renament {
+ struct inode *dir;
+ struct dentry *dentry;
+ struct inode *inode;
+ bool is_dir;
+ int dir_nlink_delta;
+
+ /* entry for "dentry" */
+ struct buffer_head *bh;
+ struct ext4_dir_entry_2 *de;
+ int inlined;
+
+ /* entry for ".." in inode if it's a directory */
+ struct buffer_head *dir_bh;
+ struct ext4_dir_entry_2 *parent_de;
+ int dir_inlined;
+};
+
+static int ext4_rename_dir_prepare(handle_t *handle, struct ext4_renament *ent)
+{
+ int retval;
+
+ ent->dir_bh = ext4_get_first_dir_block(handle, ent->inode,
+ &retval, &ent->parent_de,
+ &ent->dir_inlined);
+ if (!ent->dir_bh)
+ return retval;
+ if (le32_to_cpu(ent->parent_de->inode) != ent->dir->i_ino)
+ return -EIO;
+ BUFFER_TRACE(ent->dir_bh, "get_write_access");
+ return ext4_journal_get_write_access(handle, ent->dir_bh);
+}
+
+static int ext4_rename_dir_finish(handle_t *handle, struct ext4_renament *ent,
+ unsigned dir_ino)
+{
+ int retval;
+
+ ent->parent_de->inode = cpu_to_le32(dir_ino);
+ BUFFER_TRACE(ent->dir_bh, "call ext4_handle_dirty_metadata");
+ if (!ent->dir_inlined) {
+ if (is_dx(ent->inode)) {
+ retval = ext4_handle_dirty_dx_node(handle,
+ ent->inode,
+ ent->dir_bh);
+ } else {
+ retval = ext4_handle_dirty_dirent_node(handle,
+ ent->inode,
+ ent->dir_bh);
+ }
+ } else {
+ retval = ext4_mark_inode_dirty(handle, ent->inode);
+ }
+ if (retval) {
+ ext4_std_error(ent->dir->i_sb, retval);
+ return retval;
+ }
+ return 0;
+}
+
+static int ext4_setent(handle_t *handle, struct ext4_renament *ent,
+ unsigned ino, unsigned file_type)
+{
+ int retval;
+
+ BUFFER_TRACE(ent->bh, "get write access");
+ retval = ext4_journal_get_write_access(handle, ent->bh);
+ if (retval)
+ return retval;
+ ent->de->inode = cpu_to_le32(ino);
+ if (EXT4_HAS_INCOMPAT_FEATURE(ent->dir->i_sb,
+ EXT4_FEATURE_INCOMPAT_FILETYPE))
+ ent->de->file_type = file_type;
+ ent->dir->i_version++;
+ ent->dir->i_ctime = ent->dir->i_mtime =
+ ext4_current_time(ent->dir);
+ ext4_mark_inode_dirty(handle, ent->dir);
+ BUFFER_TRACE(ent->bh, "call ext4_handle_dirty_metadata");
+ if (!ent->inlined) {
+ retval = ext4_handle_dirty_dirent_node(handle,
+ ent->dir, ent->bh);
+ if (unlikely(retval)) {
+ ext4_std_error(ent->dir->i_sb, retval);
+ return retval;
+ }
+ }
+ brelse(ent->bh);
+ ent->bh = NULL;
+
+ return 0;
+}
+
+static int ext4_find_delete_entry(handle_t *handle, struct inode *dir,
+ const struct qstr *d_name)
+{
+ int retval = -ENOENT;
+ struct buffer_head *bh;
+ struct ext4_dir_entry_2 *de;
+
+ bh = ext4_find_entry(dir, d_name, &de, NULL);
+ if (bh) {
+ retval = ext4_delete_entry(handle, dir, de, bh);
+ brelse(bh);
+ }
+ return retval;
+}
+
+static void ext4_rename_delete(handle_t *handle, struct ext4_renament *ent)
+{
+ int retval;
+ /*
+ * ent->de could have moved from under us during htree split, so make
+ * sure that we are deleting the right entry. We might also be pointing
+ * to a stale entry in the unused part of ent->bh so just checking inum
+ * and the name isn't enough.
+ */
+ if (le32_to_cpu(ent->de->inode) != ent->inode->i_ino ||
+ ent->de->name_len != ent->dentry->d_name.len ||
+ strncmp(ent->de->name, ent->dentry->d_name.name,
+ ent->de->name_len)) {
+ retval = ext4_find_delete_entry(handle, ent->dir,
+ &ent->dentry->d_name);
+ } else {
+ retval = ext4_delete_entry(handle, ent->dir, ent->de, ent->bh);
+ if (retval == -ENOENT) {
+ retval = ext4_find_delete_entry(handle, ent->dir,
+ &ent->dentry->d_name);
+ }
+ }
+
+ if (retval) {
+ ext4_warning(ent->dir->i_sb,
+ "Deleting old file (%lu), %d, error=%d",
+ ent->dir->i_ino, ent->dir->i_nlink, retval);
+ }
+}
+
+static void ext4_update_dir_count(handle_t *handle, struct ext4_renament *ent)
+{
+ if (ent->dir_nlink_delta) {
+ if (ent->dir_nlink_delta == -1)
+ ext4_dec_count(handle, ent->dir);
+ else
+ ext4_inc_count(handle, ent->dir);
+ ext4_mark_inode_dirty(handle, ent->dir);
+ }
+}
+
/*
* Anybody can rename anything with this: the permission checks are left to the
* higher-level routines.
@@ -3012,198 +3160,267 @@ static int ext4_rename(struct inode *old_dir, struct dentry *old_dentry,
struct inode *new_dir, struct dentry *new_dentry)
{
handle_t *handle = NULL;
- struct inode *old_inode, *new_inode;
- struct buffer_head *old_bh, *new_bh, *dir_bh;
- struct ext4_dir_entry_2 *old_de, *new_de;
+ struct ext4_renament old = {
+ .dir = old_dir,
+ .dentry = old_dentry,
+ .inode = old_dentry->d_inode,
+ };
+ struct ext4_renament new = {
+ .dir = new_dir,
+ .dentry = new_dentry,
+ .inode = new_dentry->d_inode,
+ };
int retval;
- int inlined = 0, new_inlined = 0;
- struct ext4_dir_entry_2 *parent_de;
- dquot_initialize(old_dir);
- dquot_initialize(new_dir);
-
- old_bh = new_bh = dir_bh = NULL;
+ dquot_initialize(old.dir);
+ dquot_initialize(new.dir);
/* Initialize quotas before so that eventual writes go
* in separate transaction */
- if (new_dentry->d_inode)
- dquot_initialize(new_dentry->d_inode);
+ if (new.inode)
+ dquot_initialize(new.inode);
- old_bh = ext4_find_entry(old_dir, &old_dentry->d_name, &old_de, NULL);
+ old.bh = ext4_find_entry(old.dir, &old.dentry->d_name, &old.de, NULL);
/*
* Check for inode number is _not_ due to possible IO errors.
* We might rmdir the source, keep it as pwd of some process
* and merrily kill the link to whatever was created under the
* same name. Goodbye sticky bit ;-<
*/
- old_inode = old_dentry->d_inode;
retval = -ENOENT;
- if (!old_bh || le32_to_cpu(old_de->inode) != old_inode->i_ino)
+ if (!old.bh || le32_to_cpu(old.de->inode) != old.inode->i_ino)
goto end_rename;
- new_inode = new_dentry->d_inode;
- new_bh = ext4_find_entry(new_dir, &new_dentry->d_name,
- &new_de, &new_inlined);
- if (new_bh) {
- if (!new_inode) {
- brelse(new_bh);
- new_bh = NULL;
+ new.bh = ext4_find_entry(new.dir, &new.dentry->d_name,
+ &new.de, &new.inlined);
+ if (new.bh) {
+ if (!new.inode) {
+ brelse(new.bh);
+ new.bh = NULL;
}
}
- if (new_inode && !test_opt(new_dir->i_sb, NO_AUTO_DA_ALLOC))
- ext4_alloc_da_blocks(old_inode);
+ if (new.inode && !test_opt(new.dir->i_sb, NO_AUTO_DA_ALLOC))
+ ext4_alloc_da_blocks(old.inode);
- handle = ext4_journal_start(old_dir, EXT4_HT_DIR,
- (2 * EXT4_DATA_TRANS_BLOCKS(old_dir->i_sb) +
+ handle = ext4_journal_start(old.dir, EXT4_HT_DIR,
+ (2 * EXT4_DATA_TRANS_BLOCKS(old.dir->i_sb) +
EXT4_INDEX_EXTRA_TRANS_BLOCKS + 2));
if (IS_ERR(handle))
return PTR_ERR(handle);
- if (IS_DIRSYNC(old_dir) || IS_DIRSYNC(new_dir))
+ if (IS_DIRSYNC(old.dir) || IS_DIRSYNC(new.dir))
ext4_handle_sync(handle);
- if (S_ISDIR(old_inode->i_mode)) {
- if (new_inode) {
+ if (S_ISDIR(old.inode->i_mode)) {
+ if (new.inode) {
retval = -ENOTEMPTY;
- if (!empty_dir(new_inode))
+ if (!empty_dir(new.inode))
+ goto end_rename;
+ } else {
+ retval = -EMLINK;
+ if (new.dir != old.dir && EXT4_DIR_LINK_MAX(new.dir))
goto end_rename;
}
- retval = -EIO;
- dir_bh = ext4_get_first_dir_block(handle, old_inode,
- &retval, &parent_de,
- &inlined);
- if (!dir_bh)
- goto end_rename;
- if (le32_to_cpu(parent_de->inode) != old_dir->i_ino)
- goto end_rename;
- retval = -EMLINK;
- if (!new_inode && new_dir != old_dir &&
- EXT4_DIR_LINK_MAX(new_dir))
- goto end_rename;
- BUFFER_TRACE(dir_bh, "get_write_access");
- retval = ext4_journal_get_write_access(handle, dir_bh);
+ retval = ext4_rename_dir_prepare(handle, &old);
if (retval)
goto end_rename;
}
- if (!new_bh) {
- retval = ext4_add_entry(handle, new_dentry, old_inode);
+ if (!new.bh) {
+ retval = ext4_add_entry(handle, new.dentry, old.inode);
if (retval)
goto end_rename;
} else {
- BUFFER_TRACE(new_bh, "get write access");
- retval = ext4_journal_get_write_access(handle, new_bh);
+ retval = ext4_setent(handle, &new,
+ old.inode->i_ino, old.de->file_type);
if (retval)
goto end_rename;
- new_de->inode = cpu_to_le32(old_inode->i_ino);
- if (EXT4_HAS_INCOMPAT_FEATURE(new_dir->i_sb,
- EXT4_FEATURE_INCOMPAT_FILETYPE))
- new_de->file_type = old_de->file_type;
- new_dir->i_version++;
- new_dir->i_ctime = new_dir->i_mtime =
- ext4_current_time(new_dir);
- ext4_mark_inode_dirty(handle, new_dir);
- BUFFER_TRACE(new_bh, "call ext4_handle_dirty_metadata");
- if (!new_inlined) {
- retval = ext4_handle_dirty_dirent_node(handle,
- new_dir, new_bh);
- if (unlikely(retval)) {
- ext4_std_error(new_dir->i_sb, retval);
- goto end_rename;
- }
- }
- brelse(new_bh);
- new_bh = NULL;
}
/*
* Like most other Unix systems, set the ctime for inodes on a
* rename.
*/
- old_inode->i_ctime = ext4_current_time(old_inode);
- ext4_mark_inode_dirty(handle, old_inode);
+ old.inode->i_ctime = ext4_current_time(old.inode);
+ ext4_mark_inode_dirty(handle, old.inode);
/*
* ok, that's it
*/
- if (le32_to_cpu(old_de->inode) != old_inode->i_ino ||
- old_de->name_len != old_dentry->d_name.len ||
- strncmp(old_de->name, old_dentry->d_name.name, old_de->name_len) ||
- (retval = ext4_delete_entry(handle, old_dir,
- old_de, old_bh)) == -ENOENT) {
- /* old_de could have moved from under us during htree split, so
- * make sure that we are deleting the right entry. We might
- * also be pointing to a stale entry in the unused part of
- * old_bh so just checking inum and the name isn't enough. */
- struct buffer_head *old_bh2;
- struct ext4_dir_entry_2 *old_de2;
-
- old_bh2 = ext4_find_entry(old_dir, &old_dentry->d_name,
- &old_de2, NULL);
- if (old_bh2) {
- retval = ext4_delete_entry(handle, old_dir,
- old_de2, old_bh2);
- brelse(old_bh2);
- }
+ ext4_rename_delete(handle, &old);
+
+ if (new.inode) {
+ ext4_dec_count(handle, new.inode);
+ new.inode->i_ctime = ext4_current_time(new.inode);
}
- if (retval) {
- ext4_warning(old_dir->i_sb,
- "Deleting old file (%lu), %d, error=%d",
- old_dir->i_ino, old_dir->i_nlink, retval);
- }
-
- if (new_inode) {
- ext4_dec_count(handle, new_inode);
- new_inode->i_ctime = ext4_current_time(new_inode);
- }
- old_dir->i_ctime = old_dir->i_mtime = ext4_current_time(old_dir);
- ext4_update_dx_flag(old_dir);
- if (dir_bh) {
- parent_de->inode = cpu_to_le32(new_dir->i_ino);
- BUFFER_TRACE(dir_bh, "call ext4_handle_dirty_metadata");
- if (!inlined) {
- if (is_dx(old_inode)) {
- retval = ext4_handle_dirty_dx_node(handle,
- old_inode,
- dir_bh);
- } else {
- retval = ext4_handle_dirty_dirent_node(handle,
- old_inode, dir_bh);
- }
- } else {
- retval = ext4_mark_inode_dirty(handle, old_inode);
- }
- if (retval) {
- ext4_std_error(old_dir->i_sb, retval);
+ old.dir->i_ctime = old.dir->i_mtime = ext4_current_time(old.dir);
+ ext4_update_dx_flag(old.dir);
+ if (old.dir_bh) {
+ retval = ext4_rename_dir_finish(handle, &old, new.dir->i_ino);
+ if (retval)
goto end_rename;
- }
- ext4_dec_count(handle, old_dir);
- if (new_inode) {
+
+ ext4_dec_count(handle, old.dir);
+ if (new.inode) {
/* checked empty_dir above, can't have another parent,
* ext4_dec_count() won't work for many-linked dirs */
- clear_nlink(new_inode);
+ clear_nlink(new.inode);
} else {
- ext4_inc_count(handle, new_dir);
- ext4_update_dx_flag(new_dir);
- ext4_mark_inode_dirty(handle, new_dir);
+ ext4_inc_count(handle, new.dir);
+ ext4_update_dx_flag(new.dir);
+ ext4_mark_inode_dirty(handle, new.dir);
}
}
- ext4_mark_inode_dirty(handle, old_dir);
- if (new_inode) {
- ext4_mark_inode_dirty(handle, new_inode);
- if (!new_inode->i_nlink)
- ext4_orphan_add(handle, new_inode);
+ ext4_mark_inode_dirty(handle, old.dir);
+ if (new.inode) {
+ ext4_mark_inode_dirty(handle, new.inode);
+ if (!new.inode->i_nlink)
+ ext4_orphan_add(handle, new.inode);
}
retval = 0;
end_rename:
- brelse(dir_bh);
- brelse(old_bh);
- brelse(new_bh);
+ brelse(old.dir_bh);
+ brelse(old.bh);
+ brelse(new.bh);
if (handle)
ext4_journal_stop(handle);
return retval;
}
+static int ext4_cross_rename(struct inode *old_dir, struct dentry *old_dentry,
+ struct inode *new_dir, struct dentry *new_dentry)
+{
+ handle_t *handle = NULL;
+ struct ext4_renament old = {
+ .dir = old_dir,
+ .dentry = old_dentry,
+ .inode = old_dentry->d_inode,
+ };
+ struct ext4_renament new = {
+ .dir = new_dir,
+ .dentry = new_dentry,
+ .inode = new_dentry->d_inode,
+ };
+ u8 new_file_type;
+ int retval;
+
+ dquot_initialize(old.dir);
+ dquot_initialize(new.dir);
+
+ old.bh = ext4_find_entry(old.dir, &old.dentry->d_name,
+ &old.de, &old.inlined);
+ /*
+ * Check for inode number is _not_ due to possible IO errors.
+ * We might rmdir the source, keep it as pwd of some process
+ * and merrily kill the link to whatever was created under the
+ * same name. Goodbye sticky bit ;-<
+ */
+ retval = -ENOENT;
+ if (!old.bh || le32_to_cpu(old.de->inode) != old.inode->i_ino)
+ goto end_rename;
+
+ new.bh = ext4_find_entry(new.dir, &new.dentry->d_name,
+ &new.de, &new.inlined);
+
+ /* RENAME_EXCHANGE case: old *and* new must both exist */
+ if (!new.bh || le32_to_cpu(new.de->inode) != new.inode->i_ino)
+ goto end_rename;
+
+ handle = ext4_journal_start(old.dir, EXT4_HT_DIR,
+ (2 * EXT4_DATA_TRANS_BLOCKS(old.dir->i_sb) +
+ 2 * EXT4_INDEX_EXTRA_TRANS_BLOCKS + 2));
+ if (IS_ERR(handle))
+ return PTR_ERR(handle);
+
+ if (IS_DIRSYNC(old.dir) || IS_DIRSYNC(new.dir))
+ ext4_handle_sync(handle);
+
+ if (S_ISDIR(old.inode->i_mode)) {
+ old.is_dir = true;
+ retval = ext4_rename_dir_prepare(handle, &old);
+ if (retval)
+ goto end_rename;
+ }
+ if (S_ISDIR(new.inode->i_mode)) {
+ new.is_dir = true;
+ retval = ext4_rename_dir_prepare(handle, &new);
+ if (retval)
+ goto end_rename;
+ }
+
+ /*
+ * Other than the special case of overwriting a directory, parents'
+ * nlink only needs to be modified if this is a cross directory rename.
+ */
+ if (old.dir != new.dir && old.is_dir != new.is_dir) {
+ old.dir_nlink_delta = old.is_dir ? -1 : 1;
+ new.dir_nlink_delta = -old.dir_nlink_delta;
+ retval = -EMLINK;
+ if ((old.dir_nlink_delta > 0 && EXT4_DIR_LINK_MAX(old.dir)) ||
+ (new.dir_nlink_delta > 0 && EXT4_DIR_LINK_MAX(new.dir)))
+ goto end_rename;
+ }
+
+ new_file_type = new.de->file_type;
+ retval = ext4_setent(handle, &new, old.inode->i_ino, old.de->file_type);
+ if (retval)
+ goto end_rename;
+
+ retval = ext4_setent(handle, &old, new.inode->i_ino, new_file_type);
+ if (retval)
+ goto end_rename;
+
+ /*
+ * Like most other Unix systems, set the ctime for inodes on a
+ * rename.
+ */
+ old.inode->i_ctime = ext4_current_time(old.inode);
+ new.inode->i_ctime = ext4_current_time(new.inode);
+ ext4_mark_inode_dirty(handle, old.inode);
+ ext4_mark_inode_dirty(handle, new.inode);
+
+ if (old.dir_bh) {
+ retval = ext4_rename_dir_finish(handle, &old, new.dir->i_ino);
+ if (retval)
+ goto end_rename;
+ }
+ if (new.dir_bh) {
+ retval = ext4_rename_dir_finish(handle, &new, old.dir->i_ino);
+ if (retval)
+ goto end_rename;
+ }
+ ext4_update_dir_count(handle, &old);
+ ext4_update_dir_count(handle, &new);
+ retval = 0;
+
+end_rename:
+ brelse(old.dir_bh);
+ brelse(new.dir_bh);
+ brelse(old.bh);
+ brelse(new.bh);
+ if (handle)
+ ext4_journal_stop(handle);
+ return retval;
+}
+
+static int ext4_rename2(struct inode *old_dir, struct dentry *old_dentry,
+ struct inode *new_dir, struct dentry *new_dentry,
+ unsigned int flags)
+{
+ if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE))
+ return -EINVAL;
+
+ if (flags & RENAME_EXCHANGE) {
+ return ext4_cross_rename(old_dir, old_dentry,
+ new_dir, new_dentry);
+ }
+ /*
+ * Existence checking was done by the VFS, otherwise "RENAME_NOREPLACE"
+ * is equivalent to regular rename.
+ */
+ return ext4_rename(old_dir, old_dentry, new_dir, new_dentry);
+}
+
/*
* directories can handle most operations...
*/
@@ -3218,6 +3435,7 @@ const struct inode_operations ext4_dir_inode_operations = {
.mknod = ext4_mknod,
.tmpfile = ext4_tmpfile,
.rename = ext4_rename,
+ .rename2 = ext4_rename2,
.setattr = ext4_setattr,
.setxattr = generic_setxattr,
.getxattr = generic_getxattr,
diff --git a/fs/inode.c b/fs/inode.c
index e6905152c39f..fb59ba7967f1 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -944,24 +944,22 @@ EXPORT_SYMBOL(unlock_new_inode);
/**
* lock_two_nondirectories - take two i_mutexes on non-directory objects
+ *
+ * Lock any non-NULL argument that is not a directory.
+ * Zero, one or two objects may be locked by this function.
+ *
* @inode1: first inode to lock
* @inode2: second inode to lock
*/
void lock_two_nondirectories(struct inode *inode1, struct inode *inode2)
{
- WARN_ON_ONCE(S_ISDIR(inode1->i_mode));
- if (inode1 == inode2 || !inode2) {
- mutex_lock(&inode1->i_mutex);
- return;
- }
- WARN_ON_ONCE(S_ISDIR(inode2->i_mode));
- if (inode1 < inode2) {
+ if (inode1 > inode2)
+ swap(inode1, inode2);
+
+ if (inode1 && !S_ISDIR(inode1->i_mode))
mutex_lock(&inode1->i_mutex);
+ if (inode2 && !S_ISDIR(inode2->i_mode) && inode2 != inode1)
mutex_lock_nested(&inode2->i_mutex, I_MUTEX_NONDIR2);
- } else {
- mutex_lock(&inode2->i_mutex);
- mutex_lock_nested(&inode1->i_mutex, I_MUTEX_NONDIR2);
- }
}
EXPORT_SYMBOL(lock_two_nondirectories);
@@ -972,8 +970,9 @@ EXPORT_SYMBOL(lock_two_nondirectories);
*/
void unlock_two_nondirectories(struct inode *inode1, struct inode *inode2)
{
- mutex_unlock(&inode1->i_mutex);
- if (inode2 && inode2 != inode1)
+ if (inode1 && !S_ISDIR(inode1->i_mode))
+ mutex_unlock(&inode1->i_mutex);
+ if (inode2 && !S_ISDIR(inode2->i_mode) && inode2 != inode1)
mutex_unlock(&inode2->i_mutex);
}
EXPORT_SYMBOL(unlock_two_nondirectories);
diff --git a/fs/namei.c b/fs/namei.c
index 4b491b431990..c1178880f23c 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -1796,7 +1796,7 @@ static int link_path_walk(const char *name, struct nameidata *nd)
if (err)
return err;
}
- if (!d_is_directory(nd->path.dentry)) {
+ if (!d_can_lookup(nd->path.dentry)) {
err = -ENOTDIR;
break;
}
@@ -1817,7 +1817,7 @@ static int path_init(int dfd, const char *name, unsigned int flags,
struct dentry *root = nd->root.dentry;
struct inode *inode = root->d_inode;
if (*name) {
- if (!d_is_directory(root))
+ if (!d_can_lookup(root))
return -ENOTDIR;
retval = inode_permission(inode, MAY_EXEC);
if (retval)
@@ -1873,7 +1873,7 @@ static int path_init(int dfd, const char *name, unsigned int flags,
dentry = f.file->f_path.dentry;
if (*name) {
- if (!d_is_directory(dentry)) {
+ if (!d_can_lookup(dentry)) {
fdput(f);
return -ENOTDIR;
}
@@ -1955,7 +1955,7 @@ static int path_lookupat(int dfd, const char *name,
err = complete_walk(nd);
if (!err && nd->flags & LOOKUP_DIRECTORY) {
- if (!d_is_directory(nd->path.dentry)) {
+ if (!d_can_lookup(nd->path.dentry)) {
path_put(&nd->path);
err = -ENOTDIR;
}
@@ -2414,11 +2414,11 @@ static int may_delete(struct inode *dir, struct dentry *victim, bool isdir)
IS_IMMUTABLE(inode) || IS_SWAPFILE(inode))
return -EPERM;
if (isdir) {
- if (!d_is_directory(victim) && !d_is_autodir(victim))
+ if (!d_is_dir(victim))
return -ENOTDIR;
if (IS_ROOT(victim))
return -EBUSY;
- } else if (d_is_directory(victim) || d_is_autodir(victim))
+ } else if (d_is_dir(victim))
return -EISDIR;
if (IS_DEADDIR(dir))
return -ENOENT;
@@ -3016,11 +3016,10 @@ finish_open:
}
audit_inode(name, nd->path.dentry, 0);
error = -EISDIR;
- if ((open_flag & O_CREAT) &&
- (d_is_directory(nd->path.dentry) || d_is_autodir(nd->path.dentry)))
+ if ((open_flag & O_CREAT) && d_is_dir(nd->path.dentry))
goto out;
error = -ENOTDIR;
- if ((nd->flags & LOOKUP_DIRECTORY) && !d_is_directory(nd->path.dentry))
+ if ((nd->flags & LOOKUP_DIRECTORY) && !d_can_lookup(nd->path.dentry))
goto out;
if (!S_ISREG(nd->inode->i_mode))
will_truncate = false;
@@ -3744,7 +3743,7 @@ exit1:
slashes:
if (d_is_negative(dentry))
error = -ENOENT;
- else if (d_is_directory(dentry) || d_is_autodir(dentry))
+ else if (d_is_dir(dentry))
error = -EISDIR;
else
error = -ENOTDIR;
@@ -3974,7 +3973,28 @@ SYSCALL_DEFINE2(link, const char __user *, oldname, const char __user *, newname
return sys_linkat(AT_FDCWD, oldname, AT_FDCWD, newname, 0);
}
-/*
+/**
+ * vfs_rename - rename a filesystem object
+ * @old_dir: parent of source
+ * @old_dentry: source
+ * @new_dir: parent of destination
+ * @new_dentry: destination
+ * @delegated_inode: returns an inode needing a delegation break
+ * @flags: rename flags
+ *
+ * The caller must hold multiple mutexes--see lock_rename()).
+ *
+ * If vfs_rename discovers a delegation in need of breaking at either
+ * the source or destination, it will return -EWOULDBLOCK and return a
+ * reference to the inode in delegated_inode. The caller should then
+ * break the delegation and retry. Because breaking a delegation may
+ * take a long time, the caller should drop all locks before doing
+ * so.
+ *
+ * Alternatively, a caller may pass NULL for delegated_inode. This may
+ * be appropriate for callers that expect the underlying filesystem not
+ * to be NFS exported.
+ *
* The worst of all namespace operations - renaming directory. "Perverted"
* doesn't even start to describe it. Somebody in UCB had a heck of a trip...
* Problems:
@@ -4002,163 +4022,139 @@ SYSCALL_DEFINE2(link, const char __user *, oldname, const char __user *, newname
* ->i_mutex on parents, which works but leads to some truly excessive
* locking].
*/
-static int vfs_rename_dir(struct inode *old_dir, struct dentry *old_dentry,
- struct inode *new_dir, struct dentry *new_dentry)
+int vfs_rename(struct inode *old_dir, struct dentry *old_dentry,
+ struct inode *new_dir, struct dentry *new_dentry,
+ struct inode **delegated_inode, unsigned int flags)
{
- int error = 0;
+ int error;
+ bool is_dir = d_is_dir(old_dentry);
+ const unsigned char *old_name;
+ struct inode *source = old_dentry->d_inode;
struct inode *target = new_dentry->d_inode;
+ bool new_is_dir = false;
unsigned max_links = new_dir->i_sb->s_max_links;
+ if (source == target)
+ return 0;
+
+ error = may_delete(old_dir, old_dentry, is_dir);
+ if (error)
+ return error;
+
+ if (!target) {
+ error = may_create(new_dir, new_dentry);
+ } else {
+ new_is_dir = d_is_dir(new_dentry);
+
+ if (!(flags & RENAME_EXCHANGE))
+ error = may_delete(new_dir, new_dentry, is_dir);
+ else
+ error = may_delete(new_dir, new_dentry, new_is_dir);
+ }
+ if (error)
+ return error;
+
+ if (!old_dir->i_op->rename)
+ return -EPERM;
+
+ if (flags && !old_dir->i_op->rename2)
+ return -EINVAL;
+
/*
* If we are going to change the parent - check write permissions,
* we'll need to flip '..'.
*/
if (new_dir != old_dir) {
- error = inode_permission(old_dentry->d_inode, MAY_WRITE);
- if (error)
- return error;
+ if (is_dir) {
+ error = inode_permission(source, MAY_WRITE);
+ if (error)
+ return error;
+ }
+ if ((flags & RENAME_EXCHANGE) && new_is_dir) {
+ error = inode_permission(target, MAY_WRITE);
+ if (error)
+ return error;
+ }
}
- error = security_inode_rename(old_dir, old_dentry, new_dir, new_dentry);
+ error = security_inode_rename(old_dir, old_dentry, new_dir, new_dentry,
+ flags);
if (error)
return error;
+ old_name = fsnotify_oldname_init(old_dentry->d_name.name);
dget(new_dentry);
- if (target)
+ if (!is_dir || (flags & RENAME_EXCHANGE))
+ lock_two_nondirectories(source, target);
+ else if (target)
mutex_lock(&target->i_mutex);
error = -EBUSY;
if (d_mountpoint(old_dentry) || d_mountpoint(new_dentry))
goto out;
- error = -EMLINK;
- if (max_links && !target && new_dir != old_dir &&
- new_dir->i_nlink >= max_links)
- goto out;
-
- if (target)
+ if (max_links && new_dir != old_dir) {
+ error = -EMLINK;
+ if (is_dir && !new_is_dir && new_dir->i_nlink >= max_links)
+ goto out;
+ if ((flags & RENAME_EXCHANGE) && !is_dir && new_is_dir &&
+ old_dir->i_nlink >= max_links)
+ goto out;
+ }
+ if (is_dir && !(flags & RENAME_EXCHANGE) && target)
shrink_dcache_parent(new_dentry);
- error = old_dir->i_op->rename(old_dir, old_dentry, new_dir, new_dentry);
- if (error)
- goto out;
-
- if (target) {
- target->i_flags |= S_DEAD;
- dont_mount(new_dentry);
+ if (!is_dir) {
+ error = try_break_deleg(source, delegated_inode);
+ if (error)
+ goto out;
}
-out:
- if (target)
- mutex_unlock(&target->i_mutex);
- dput(new_dentry);
- if (!error)
- if (!(old_dir->i_sb->s_type->fs_flags & FS_RENAME_DOES_D_MOVE))
- d_move(old_dentry,new_dentry);
- return error;
-}
-
-static int vfs_rename_other(struct inode *old_dir, struct dentry *old_dentry,
- struct inode *new_dir, struct dentry *new_dentry,
- struct inode **delegated_inode)
-{
- struct inode *target = new_dentry->d_inode;
- struct inode *source = old_dentry->d_inode;
- int error;
-
- error = security_inode_rename(old_dir, old_dentry, new_dir, new_dentry);
- if (error)
- return error;
-
- dget(new_dentry);
- lock_two_nondirectories(source, target);
-
- error = -EBUSY;
- if (d_mountpoint(old_dentry)||d_mountpoint(new_dentry))
- goto out;
-
- error = try_break_deleg(source, delegated_inode);
- if (error)
- goto out;
- if (target) {
+ if (target && !new_is_dir) {
error = try_break_deleg(target, delegated_inode);
if (error)
goto out;
}
- error = old_dir->i_op->rename(old_dir, old_dentry, new_dir, new_dentry);
+ if (!flags) {
+ error = old_dir->i_op->rename(old_dir, old_dentry,
+ new_dir, new_dentry);
+ } else {
+ error = old_dir->i_op->rename2(old_dir, old_dentry,
+ new_dir, new_dentry, flags);
+ }
if (error)
goto out;
- if (target)
+ if (!(flags & RENAME_EXCHANGE) && target) {
+ if (is_dir)
+ target->i_flags |= S_DEAD;
dont_mount(new_dentry);
- if (!(old_dir->i_sb->s_type->fs_flags & FS_RENAME_DOES_D_MOVE))
- d_move(old_dentry, new_dentry);
+ }
+ if (!(old_dir->i_sb->s_type->fs_flags & FS_RENAME_DOES_D_MOVE)) {
+ if (!(flags & RENAME_EXCHANGE))
+ d_move(old_dentry, new_dentry);
+ else
+ d_exchange(old_dentry, new_dentry);
+ }
out:
- unlock_two_nondirectories(source, target);
+ if (!is_dir || (flags & RENAME_EXCHANGE))
+ unlock_two_nondirectories(source, target);
+ else if (target)
+ mutex_unlock(&target->i_mutex);
dput(new_dentry);
- return error;
-}
-
-/**
- * vfs_rename - rename a filesystem object
- * @old_dir: parent of source
- * @old_dentry: source
- * @new_dir: parent of destination
- * @new_dentry: destination
- * @delegated_inode: returns an inode needing a delegation break
- *
- * The caller must hold multiple mutexes--see lock_rename()).
- *
- * If vfs_rename discovers a delegation in need of breaking at either
- * the source or destination, it will return -EWOULDBLOCK and return a
- * reference to the inode in delegated_inode. The caller should then
- * break the delegation and retry. Because breaking a delegation may
- * take a long time, the caller should drop all locks before doing
- * so.
- *
- * Alternatively, a caller may pass NULL for delegated_inode. This may
- * be appropriate for callers that expect the underlying filesystem not
- * to be NFS exported.
- */
-int vfs_rename(struct inode *old_dir, struct dentry *old_dentry,
- struct inode *new_dir, struct dentry *new_dentry,
- struct inode **delegated_inode)
-{
- int error;
- int is_dir = d_is_directory(old_dentry) || d_is_autodir(old_dentry);
- const unsigned char *old_name;
-
- if (old_dentry->d_inode == new_dentry->d_inode)
- return 0;
-
- error = may_delete(old_dir, old_dentry, is_dir);
- if (error)
- return error;
-
- if (!new_dentry->d_inode)
- error = may_create(new_dir, new_dentry);
- else
- error = may_delete(new_dir, new_dentry, is_dir);
- if (error)
- return error;
-
- if (!old_dir->i_op->rename)
- return -EPERM;
-
- old_name = fsnotify_oldname_init(old_dentry->d_name.name);
-
- if (is_dir)
- error = vfs_rename_dir(old_dir,old_dentry,new_dir,new_dentry);
- else
- error = vfs_rename_other(old_dir,old_dentry,new_dir,new_dentry,delegated_inode);
- if (!error)
+ if (!error) {
fsnotify_move(old_dir, new_dir, old_name, is_dir,
- new_dentry->d_inode, old_dentry);
+ !(flags & RENAME_EXCHANGE) ? target : NULL, old_dentry);
+ if (flags & RENAME_EXCHANGE) {
+ fsnotify_move(new_dir, old_dir, old_dentry->d_name.name,
+ new_is_dir, NULL, new_dentry);
+ }
+ }
fsnotify_oldname_free(old_name);
return error;
}
-SYSCALL_DEFINE4(renameat, int, olddfd, const char __user *, oldname,
- int, newdfd, const char __user *, newname)
+SYSCALL_DEFINE5(renameat2, int, olddfd, const char __user *, oldname,
+ int, newdfd, const char __user *, newname, unsigned int, flags)
{
struct dentry *old_dir, *new_dir;
struct dentry *old_dentry, *new_dentry;
@@ -4170,6 +4166,13 @@ SYSCALL_DEFINE4(renameat, int, olddfd, const char __user *, oldname,
unsigned int lookup_flags = 0;
bool should_retry = false;
int error;
+
+ if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE))
+ return -EINVAL;
+
+ if ((flags & RENAME_NOREPLACE) && (flags & RENAME_EXCHANGE))
+ return -EINVAL;
+
retry:
from = user_path_parent(olddfd, oldname, &oldnd, lookup_flags);
if (IS_ERR(from)) {
@@ -4193,6 +4196,8 @@ retry:
goto exit2;
new_dir = newnd.path.dentry;
+ if (flags & RENAME_NOREPLACE)
+ error = -EEXIST;
if (newnd.last_type != LAST_NORM)
goto exit2;
@@ -4202,7 +4207,8 @@ retry:
oldnd.flags &= ~LOOKUP_PARENT;
newnd.flags &= ~LOOKUP_PARENT;
- newnd.flags |= LOOKUP_RENAME_TARGET;
+ if (!(flags & RENAME_EXCHANGE))
+ newnd.flags |= LOOKUP_RENAME_TARGET;
retry_deleg:
trap = lock_rename(new_dir, old_dir);
@@ -4215,34 +4221,49 @@ retry_deleg:
error = -ENOENT;
if (d_is_negative(old_dentry))
goto exit4;
+ new_dentry = lookup_hash(&newnd);
+ error = PTR_ERR(new_dentry);
+ if (IS_ERR(new_dentry))
+ goto exit4;
+ error = -EEXIST;
+ if ((flags & RENAME_NOREPLACE) && d_is_positive(new_dentry))
+ goto exit5;
+ if (flags & RENAME_EXCHANGE) {
+ error = -ENOENT;
+ if (d_is_negative(new_dentry))
+ goto exit5;
+
+ if (!d_is_dir(new_dentry)) {
+ error = -ENOTDIR;
+ if (newnd.last.name[newnd.last.len])
+ goto exit5;
+ }
+ }
/* unless the source is a directory trailing slashes give -ENOTDIR */
- if (!d_is_directory(old_dentry) && !d_is_autodir(old_dentry)) {
+ if (!d_is_dir(old_dentry)) {
error = -ENOTDIR;
if (oldnd.last.name[oldnd.last.len])
- goto exit4;
- if (newnd.last.name[newnd.last.len])
- goto exit4;
+ goto exit5;
+ if (!(flags & RENAME_EXCHANGE) && newnd.last.name[newnd.last.len])
+ goto exit5;
}
/* source should not be ancestor of target */
error = -EINVAL;
if (old_dentry == trap)
- goto exit4;
- new_dentry = lookup_hash(&newnd);
- error = PTR_ERR(new_dentry);
- if (IS_ERR(new_dentry))
- goto exit4;
+ goto exit5;
/* target should not be an ancestor of source */
- error = -ENOTEMPTY;
+ if (!(flags & RENAME_EXCHANGE))
+ error = -ENOTEMPTY;
if (new_dentry == trap)
goto exit5;
error = security_path_rename(&oldnd.path, old_dentry,
- &newnd.path, new_dentry);
+ &newnd.path, new_dentry, flags);
if (error)
goto exit5;
error = vfs_rename(old_dir->d_inode, old_dentry,
- new_dir->d_inode, new_dentry,
- &delegated_inode);
+ new_dir->d_inode, new_dentry,
+ &delegated_inode, flags);
exit5:
dput(new_dentry);
exit4:
@@ -4272,9 +4293,15 @@ exit:
return error;
}
+SYSCALL_DEFINE4(renameat, int, olddfd, const char __user *, oldname,
+ int, newdfd, const char __user *, newname)
+{
+ return sys_renameat2(olddfd, oldname, newdfd, newname, 0);
+}
+
SYSCALL_DEFINE2(rename, const char __user *, oldname, const char __user *, newname)
{
- return sys_renameat(AT_FDCWD, oldname, AT_FDCWD, newname);
+ return sys_renameat2(AT_FDCWD, oldname, AT_FDCWD, newname, 0);
}
int vfs_readlink(struct dentry *dentry, char __user *buffer, int buflen, const char *link)
diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
index 6d7be3f80356..915808b36df7 100644
--- a/fs/nfsd/vfs.c
+++ b/fs/nfsd/vfs.c
@@ -1694,7 +1694,7 @@ nfsd_rename(struct svc_rqst *rqstp, struct svc_fh *ffhp, char *fname, int flen,
if (ffhp->fh_export->ex_path.dentry != tfhp->fh_export->ex_path.dentry)
goto out_dput_new;
- host_err = vfs_rename(fdir, odentry, tdir, ndentry, NULL);
+ host_err = vfs_rename(fdir, odentry, tdir, ndentry, NULL, 0);
if (!host_err) {
host_err = commit_metadata(tfhp);
if (!host_err)

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