dcache: d_obtain_alias callers don't all want DISCONNECTED
There are a few d_obtain_alias callers that are using it to get the
root of a filesystem which may already have an alias somewhere else.
This is not the same as the filehandle-lookup case, and none of them
actually need DCACHE_DISCONNECTED set.
It isn't really a serious problem, but it would really be clearer if we
reserved DCACHE_DISCONNECTED for those cases where it's actually needed.
In the btrfs case this was causing a spurious printk from
nfsd/nfsfh.c:fh_verify when it found an unexpected DCACHE_DISCONNECTED
dentry. Josef worked around this by unsetting DCACHE_DISCONNECTED
manually in 3a0dfa6a12e "Btrfs: unset DCACHE_DISCONNECTED when mounting
default subvol", and this replaces that workaround.
Cc: Josef Bacik <jbacik@fb.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 8e16bca..67b48b9 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -851,7 +851,6 @@
struct btrfs_path *path;
struct btrfs_key location;
struct inode *inode;
- struct dentry *dentry;
u64 dir_id;
int new = 0;
@@ -922,13 +921,7 @@
return dget(sb->s_root);
}
- dentry = d_obtain_alias(inode);
- if (!IS_ERR(dentry)) {
- spin_lock(&dentry->d_lock);
- dentry->d_flags &= ~DCACHE_DISCONNECTED;
- spin_unlock(&dentry->d_lock);
- }
- return dentry;
+ return d_obtain_root(inode);
}
static int btrfs_fill_super(struct super_block *sb,