Btrfs: Check if btrfs_next_leaf() returns error in btrfs_listxattr()

btrfs_next_leaf() can return -errno, and we should propagate
it to userspace.

This also simplifies how we walk the btree path.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>

1 files changed, 12 insertions, 21 deletions

diff --git a/fs/btrfs/xattr.c b/fs/btrfs/xattr.c
index e5d22f280956..07b9bc350d5d 100644
--- a/fs/btrfs/xattr.c
+++ b/fs/btrfs/xattr.c
@@ -180,11 +180,10 @@ ssize_t btrfs_listxattr(struct dentry *dentry, char *buffer, size_t size)
         struct btrfs_path *path;
         struct extent_buffer *leaf;
         struct btrfs_dir_item *di;
-        int ret = 0, slot, advance;
+        int ret = 0, slot;
         size_t total_size = 0, size_left = size;
         unsigned long name_ptr;
         size_t name_len;
-        u32 nritems;
 
         /*
          * ok we want all objects associated with this id.
@@ -204,34 +203,24 @@ 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;
-        advance = 0;
+
         while (1) {
                 leaf = path->nodes[0];
-                nritems = btrfs_header_nritems(leaf);
                 slot = path->slots[0];
 
                 /* this is where we start walking through the path */
-                if (advance || slot >= nritems) {
+                if (slot >= btrfs_header_nritems(leaf)) {
                         /*
                          * if we've reached the last slot in this leaf we need
                          * to go to the next leaf and reset everything
                          */
-                        if (slot >= nritems-1) {
-                                ret = btrfs_next_leaf(root, path);
-                                if (ret)
-                                        break;
-                                leaf = path->nodes[0];
-                                nritems = btrfs_header_nritems(leaf);
-                                slot = path->slots[0];
-                        } else {
-                                /*
-                                 * just walking through the slots on this leaf
-                                 */
-                                slot++;
-                                path->slots[0]++;
-                        }
+                        ret = btrfs_next_leaf(root, path);
+                        if (ret < 0)
+                                goto err;
+                        else if (ret > 0)
+                                break;
+                        continue;
                 }
-                advance = 1;
 
                 btrfs_item_key_to_cpu(leaf, &found_key, slot);
 
@@ -250,7 +239,7 @@ ssize_t btrfs_listxattr(struct dentry *dentry, char *buffer, size_t size)
 
                 /* we are just looking for how big our buffer needs to be */
                 if (!size)
-                        continue;
+                        goto next;
 
                 if (!buffer || (name_len + 1) > size_left) {
                         ret = -ERANGE;
@@ -263,6 +252,8 @@ ssize_t btrfs_listxattr(struct dentry *dentry, char *buffer, size_t size)
 
                 size_left -= name_len + 1;
                 buffer += name_len + 1;
+next:
+                path->slots[0]++;
         }
         ret = total_size;