Always lookup priv_root on reiserfs mount and keep it
... even if it's a negative dentry. That way we can set ->d_op on
root before anyone could race with us. Simplify d_compare(), while
we are at it.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/reiserfs/xattr.c b/fs/reiserfs/xattr.c
index 31a3dbb..2891f78 100644
--- a/fs/reiserfs/xattr.c
+++ b/fs/reiserfs/xattr.c
@@ -903,16 +903,19 @@
WARN_ON_ONCE(!mutex_is_locked(&inode->i_mutex));
err = xattr_mkdir(inode, dentry, 0700);
- if (err) {
- dput(dentry);
- dentry = NULL;
+ if (err || !dentry->d_inode) {
+ reiserfs_warning(dentry->d_sb, "jdm-20006",
+ "xattrs/ACLs enabled and couldn't "
+ "find/create .reiserfs_priv. "
+ "Failing mount.");
+ return -EOPNOTSUPP;
}
- if (dentry && dentry->d_inode)
- reiserfs_info(dentry->d_sb, "Created %s - reserved for xattr "
- "storage.\n", PRIVROOT_NAME);
+ dentry->d_inode->i_flags |= S_PRIVATE;
+ reiserfs_info(dentry->d_sb, "Created %s - reserved for xattr "
+ "storage.\n", PRIVROOT_NAME);
- return err;
+ return 0;
}
static int xattr_mount_check(struct super_block *s)
@@ -944,11 +947,9 @@
xattr_lookup_poison(struct dentry *dentry, struct qstr *q1, struct qstr *name)
{
struct dentry *priv_root = REISERFS_SB(dentry->d_sb)->priv_root;
- if (name->len == priv_root->d_name.len &&
- name->hash == priv_root->d_name.hash &&
- !memcmp(name->name, priv_root->d_name.name, name->len)) {
+ if (container_of(q1, struct dentry, d_name) == priv_root)
return -ENOENT;
- } else if (q1->len == name->len &&
+ if (q1->len == name->len &&
!memcmp(q1->name, name->name, name->len))
return 0;
return 1;
@@ -958,6 +959,27 @@
.d_compare = xattr_lookup_poison,
};
+int reiserfs_lookup_privroot(struct super_block *s)
+{
+ struct dentry *dentry;
+ int err = 0;
+
+ /* If we don't have the privroot located yet - go find it */
+ mutex_lock(&s->s_root->d_inode->i_mutex);
+ dentry = lookup_one_len(PRIVROOT_NAME, s->s_root,
+ strlen(PRIVROOT_NAME));
+ if (!IS_ERR(dentry)) {
+ REISERFS_SB(s)->priv_root = dentry;
+ s->s_root->d_op = &xattr_lookup_poison_ops;
+ if (dentry->d_inode)
+ dentry->d_inode->i_flags |= S_PRIVATE;
+ } else
+ err = PTR_ERR(dentry);
+ mutex_unlock(&s->s_root->d_inode->i_mutex);
+
+ return err;
+}
+
/* We need to take a copy of the mount flags since things like
* MS_RDONLY don't get set until *after* we're called.
* mount_flags != mount_options */
@@ -969,48 +991,12 @@
err = xattr_mount_check(s);
if (err)
goto error;
-#endif
- /* If we don't have the privroot located yet - go find it */
- if (!REISERFS_SB(s)->priv_root) {
- struct dentry *dentry;
- mutex_lock_nested(&s->s_root->d_inode->i_mutex, I_MUTEX_CHILD);
- dentry = lookup_one_len(PRIVROOT_NAME, s->s_root,
- strlen(PRIVROOT_NAME));
- if (!IS_ERR(dentry)) {
-#ifdef CONFIG_REISERFS_FS_XATTR
- if (!(mount_flags & MS_RDONLY) && !dentry->d_inode)
- err = create_privroot(dentry);
-#endif
- if (!dentry->d_inode) {
- dput(dentry);
- dentry = NULL;
- }
- } else
- err = PTR_ERR(dentry);
+ if (!REISERFS_SB(s)->priv_root->d_inode && !(mount_flags & MS_RDONLY)) {
+ mutex_lock(&s->s_root->d_inode->i_mutex);
+ err = create_privroot(REISERFS_SB(s)->priv_root);
mutex_unlock(&s->s_root->d_inode->i_mutex);
-
- if (!err && dentry) {
- s->s_root->d_op = &xattr_lookup_poison_ops;
- dentry->d_inode->i_flags |= S_PRIVATE;
- REISERFS_SB(s)->priv_root = dentry;
-#ifdef CONFIG_REISERFS_FS_XATTR
- /* xattrs are unavailable */
- } else if (!(mount_flags & MS_RDONLY)) {
- /* If we're read-only it just means that the dir
- * hasn't been created. Not an error -- just no
- * xattrs on the fs. We'll check again if we
- * go read-write */
- reiserfs_warning(s, "jdm-20006",
- "xattrs/ACLs enabled and couldn't "
- "find/create .reiserfs_priv. "
- "Failing mount.");
- err = -EOPNOTSUPP;
-#endif
- }
}
-
-#ifdef CONFIG_REISERFS_FS_XATTR
if (!err)
s->s_xattr = reiserfs_xattr_handlers;