Btrfs: cleanup d_obtain_alias useage

d_obtain_alias is intended as a tailcall that can pass in errors encoded
in the inode pointer if needed, so use it that way instead of
duplicating the error handling.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Chris Mason <chris.mason@oracle.com>

diff --git a/fs/btrfs/export.c b/fs/btrfs/export.c
index 292b0b2..2b357a6 100644 (file)
--- a/fs/btrfs/export.c
+++ b/fs/btrfs/export.c
@@ -68,7 +68,6 @@ static struct dentry *btrfs_get_dentry(struct super_block *sb, u64 objectid,
 {
        struct btrfs_root *root;
        struct inode *inode;
-       struct dentry *result;
        struct btrfs_key key;
 
        key.objectid = root_objectid;
@@ -92,11 +91,7 @@ static struct dentry *btrfs_get_dentry(struct super_block *sb, u64 objectid,
                return ERR_PTR(-ESTALE);
        }
 
-       result = d_obtain_alias(inode);
-       if (!result)
-               return ERR_PTR(-ENOMEM);
-
-       return result;
+       return d_obtain_alias(inode);
 }
 
 static struct dentry *btrfs_fh_to_parent(struct super_block *sb, struct fid *fh,
@@ -148,8 +143,6 @@ static struct dentry *btrfs_fh_to_dentry(struct super_block *sb, struct fid *fh,
 static struct dentry *btrfs_get_parent(struct dentry *child)
 {
        struct inode *dir = child->d_inode;
-       struct inode *inode;
-       struct dentry *parent;
        struct btrfs_root *root = BTRFS_I(dir)->root;
        struct btrfs_key key;
        struct btrfs_path *path;
@@ -203,13 +196,7 @@ static struct dentry *btrfs_get_parent(struct dentry *child)
        btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
        key.offset = 0;
 
-       inode = btrfs_iget(root->fs_info->sb, &key, root, NULL);
-
-       parent = d_obtain_alias(inode);
-       if (!parent)
-               parent = ERR_PTR(-ENOMEM);
-
-       return parent;
+       return d_obtain_alias(btrfs_iget(root->fs_info->sb, &key, root, NULL));
 }
 
 const struct export_operations btrfs_export_ops = {