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

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, 10 insertions, 18 deletions

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 55a6a0b416d7..b9f7f5258343 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -4221,10 +4221,8 @@ static int btrfs_real_readdir(struct file *filp, void *dirent,
         struct btrfs_key found_key;
         struct btrfs_path *path;
         int ret;
-        u32 nritems;
         struct extent_buffer *leaf;
         int slot;
-        int advance;
         unsigned char d_type;
         int over = 0;
         u32 di_cur;
@@ -4267,27 +4265,19 @@ static int btrfs_real_readdir(struct file *filp, void *dirent,
         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];
-                if (advance || slot >= nritems) {
-                        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 {
-                                slot++;
-                                path->slots[0]++;
-                        }
+                if (slot >= btrfs_header_nritems(leaf)) {
+                        ret = btrfs_next_leaf(root, path);
+                        if (ret < 0)
+                                goto err;
+                        else if (ret > 0)
+                                break;
+                        continue;
                 }
 
-                advance = 1;
                 item = btrfs_item_nr(leaf, slot);
                 btrfs_item_key_to_cpu(leaf, &found_key, slot);
 
@@ -4296,7 +4286,7 @@ static int btrfs_real_readdir(struct file *filp, void *dirent,
                 if (btrfs_key_type(&found_key) != key_type)
                         break;
                 if (found_key.offset < filp->f_pos)
-                        continue;
+                        goto next;
 
                 filp->f_pos = found_key.offset;
 
@@ -4349,6 +4339,8 @@ skip:
                         di_cur += di_len;
                         di = (struct btrfs_dir_item *)((char *)di + di_len);
                 }
+next:
+                path->slots[0]++;
         }
 
         /* Reached end of directory/root. Bump pos past the last item. */