ceph: factor out ceph_lookup_inode()

This function will be used by __fh_to_dentry and by the quotas code, to
find quota realm inodes that are not visible in the mountpoint.

Signed-off-by: Luis Henriques <lhenriques@suse.com>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

2 files changed, 13 insertions, 2 deletions

diff --git a/fs/ceph/export.c b/fs/ceph/export.c
index 3c59ad180ef0..d64e7472fa41 100644
--- a/fs/ceph/export.c
+++ b/fs/ceph/export.c
@@ -59,7 +59,7 @@ static int ceph_encode_fh(struct inode *inode, u32 *rawfh, int *max_len,
         return type;
 }
 
-static struct dentry *__fh_to_dentry(struct super_block *sb, u64 ino)
+struct inode *ceph_lookup_inode(struct super_block *sb, u64 ino)
 {
         struct ceph_mds_client *mdsc = ceph_sb_to_client(sb)->mdsc;
         struct inode *inode;
@@ -91,13 +91,23 @@ static struct dentry *__fh_to_dentry(struct super_block *sb, u64 ino)
                         ihold(inode);
                 ceph_mdsc_put_request(req);
                 if (!inode)
-                        return ERR_PTR(-ESTALE);
+                        return err < 0 ? ERR_PTR(err) : ERR_PTR(-ESTALE);
                 if (inode->i_nlink == 0) {
                         iput(inode);
                         return ERR_PTR(-ESTALE);
                 }
         }
 
+        return inode;
+}
+
+static struct dentry *__fh_to_dentry(struct super_block *sb, u64 ino)
+{
+        struct inode *inode = ceph_lookup_inode(sb, ino);
+
+        if (IS_ERR(inode))
+                return ERR_CAST(inode);
+
         return d_obtain_alias(inode);
 }
 
diff --git a/fs/ceph/super.h b/fs/ceph/super.h
index 16c03188578e..976f200164f9 100644
--- a/fs/ceph/super.h
+++ b/fs/ceph/super.h
@@ -1082,6 +1082,7 @@ extern long ceph_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
 
 /* export.c */
 extern const struct export_operations ceph_export_ops;
+struct inode *ceph_lookup_inode(struct super_block *sb, u64 ino);
 
 /* locks.c */
 extern __init void ceph_flock_init(void);