Btrfs: snapshot progress

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

diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index cd40a08dd8a666af9b0a77bb7e2cf17e16101544..efc604eea0b00883e015511ac9e7b737ec2d92e8 100644 (file)
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -77,6 +77,12 @@ static int lookup_block_ref(struct btrfs_trans_handle *trans, struct btrfs_root
        return 0;
 }
 
+int btrfs_inc_root_ref(struct btrfs_trans_handle *trans,
+                      struct btrfs_root *root)
+{
+       return inc_block_ref(trans, root, root->node->b_blocknr, 1);
+}
+
 int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
                  struct buffer_head *buf)
 {
@@ -224,6 +230,7 @@ static int __free_extent(struct btrfs_trans_handle *trans, struct btrfs_root
        path = btrfs_alloc_path();
        BUG_ON(!path);
        btrfs_init_path(path);
+
        ret = btrfs_search_slot(trans, extent_root, &key, path, -1, 1);
        if (ret) {
                printk("failed to find %Lu\n", key.objectid);
@@ -339,15 +346,30 @@ static int find_free_extent(struct btrfs_trans_handle *trans, struct btrfs_root
        int total_needed = num_blocks;
        int level;
 
+       path = btrfs_alloc_path();
+       ins->flags = 0;
+       btrfs_set_key_type(ins, BTRFS_EXTENT_ITEM_KEY);
+
        level = btrfs_header_level(btrfs_buffer_header(root->node));
        total_needed += (level + 1) * 3;
+       if (root->fs_info->last_insert.objectid == 0 && search_end == (u64)-1) {
+               struct btrfs_disk_key *last_key;
+               btrfs_init_path(path);
+               ins->objectid = (u64)-1;
+               ins->offset = (u64)-1;
+               ret = btrfs_search_slot(trans, root, ins, path, 0, 0);
+               if (ret < 0)
+                       goto error;
+               BUG_ON(ret == 0);
+               if (path->slots[0] > 0)
+                       path->slots[0]--;
+               l = btrfs_buffer_leaf(path->nodes[0]);
+               last_key = &l->items[path->slots[0]].key;
+               search_start = btrfs_disk_key_objectid(last_key);
+       }
        if (root->fs_info->last_insert.objectid > search_start)
                search_start = root->fs_info->last_insert.objectid;
 
-       ins->flags = 0;
-       btrfs_set_key_type(ins, BTRFS_EXTENT_ITEM_KEY);
-       path = btrfs_alloc_path();
-
 check_failed:
        btrfs_init_path(path);
        ins->objectid = search_start;