Btrfs: cleanup xattr code

Andrew's review of the xattr code revealed some minor issues that this patch
addresses.  Just an error return fix, got rid of a useless statement and
commented one of the trickier parts of __btrfs_getxattr.

Signed-off-by: Josef Bacik <jbacik@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>

1 files changed, 12 insertions, 2 deletions

diff --git a/fs/btrfs/xattr.c b/fs/btrfs/xattr.c
index 7f332e270894..b4fa5f4b6ad1 100644
--- a/fs/btrfs/xattr.c
+++ b/fs/btrfs/xattr.c
@@ -45,9 +45,12 @@ ssize_t __btrfs_getxattr(struct inode *inode, const char *name,
         /* lookup the xattr by name */
         di = btrfs_lookup_xattr(NULL, root, path, inode->i_ino, name,
                                 strlen(name), 0);
-        if (!di || IS_ERR(di)) {
+        if (!di) {
                 ret = -ENODATA;
                 goto out;
+        } else if (IS_ERR(di)) {
+                ret = PTR_ERR(di);
+                goto out;
         }
 
         leaf = path->nodes[0];
@@ -62,6 +65,14 @@ ssize_t __btrfs_getxattr(struct inode *inode, const char *name,
                 ret = -ERANGE;
                 goto out;
         }
+
+        /*
+         * The way things are packed into the leaf is like this
+         * |struct btrfs_dir_item|name|data|
+         * where name is the xattr name, so security.foo, and data is the
+         * content of the xattr.  data_ptr points to the location in memory
+         * where the data starts in the in memory leaf
+         */
         data_ptr = (unsigned long)((char *)(di + 1) +
                                    btrfs_dir_name_len(leaf, di));
         read_extent_buffer(leaf, buffer, data_ptr,
@@ -176,7 +187,6 @@ ssize_t btrfs_listxattr(struct dentry *dentry, char *buffer, size_t size)
         ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
         if (ret < 0)
                 goto err;
-        ret = 0;
         advance = 0;
         while (1) {
                 leaf = path->nodes[0];