Btrfs: Add btree locking to the tree defragmentation code

[linux-2.6-block.git] / fs / btrfs / ctree.c

diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index 40f0e0cb804bd07f84f40d51d33dcfa7377f687f..7f4cc2b88d097a7315ba876afb2ab791b70e4330 100644 (file)
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -354,7 +354,6 @@ int btrfs_realloc_node(struct btrfs_trans_handle *trans,
                       struct btrfs_key *progress)
 {
        struct extent_buffer *cur;
-       struct extent_buffer *tmp;
        u64 blocknr;
        u64 gen;
        u64 search_start = *last_ret;
@@ -370,9 +369,6 @@ int btrfs_realloc_node(struct btrfs_trans_handle *trans,
        int progress_passed = 0;
        struct btrfs_disk_key disk_key;
 
-       /* FIXME this code needs locking */
-       return 0;
-
        parent_level = btrfs_header_level(parent);
        if (cache_only && parent_level != 1)
                return 0;
@@ -454,20 +450,23 @@ int btrfs_realloc_node(struct btrfs_trans_handle *trans,
                if (search_start == 0)
                        search_start = last_block;
 
+               btrfs_tree_lock(cur);
                err = __btrfs_cow_block(trans, root, cur, parent, i,
-                                       &tmp, search_start,
+                                       &cur, search_start,
                                        min(16 * blocksize,
                                            (end_slot - i) * blocksize));
                if (err) {
+                       btrfs_tree_unlock(cur);
                        free_extent_buffer(cur);
                        break;
                }
-               search_start = tmp->start;
-               last_block = tmp->start;
+               search_start = cur->start;
+               last_block = cur->start;
                *last_ret = search_start;
                if (parent_level == 1)
-                       btrfs_clear_buffer_defrag(tmp);
-               free_extent_buffer(tmp);
+                       btrfs_clear_buffer_defrag(cur);
+               btrfs_tree_unlock(cur);
+               free_extent_buffer(cur);
        }
        if (parent->map_token) {
                unmap_extent_buffer(parent, parent->map_token,
@@ -2970,6 +2969,35 @@ int btrfs_prev_leaf(struct btrfs_root *root, struct btrfs_path *path)
        return 1;
 }
 
+int btrfs_find_next_key(struct btrfs_root *root, struct btrfs_path *path,
+                       struct btrfs_key *key, int lowest_level)
+{
+       int level = lowest_level;
+       int slot;
+       struct extent_buffer *c;
+
+       while(level < BTRFS_MAX_LEVEL) {
+               if (!path->nodes[level])
+                       return 1;
+
+               slot = path->slots[level] + 1;
+               c = path->nodes[level];
+               if (slot >= btrfs_header_nritems(c)) {
+                       level++;
+                       if (level == BTRFS_MAX_LEVEL) {
+                               return 1;
+                       }
+                       continue;
+               }
+               if (level == 0)
+                       btrfs_item_key_to_cpu(c, key, slot);
+               else
+                       btrfs_node_key_to_cpu(c, key, slot);
+               return 0;
+       }
+       return 1;
+}
+
 /*
  * search the tree again to find a leaf with greater keys
  * returns 0 if it found something or 1 if there are no greater leaves.