- b = read_tree_block(root, bytenr,
- btrfs_level_size(root, level - 1));
- if (ptr_gen != btrfs_header_generation(b)) {
- printk("block %llu bad gen wanted %llu "
- "found %llu\n",
- (unsigned long long)b->start,
- (unsigned long long)ptr_gen,
- (unsigned long long)btrfs_header_generation(b));
+
+ blocknr = btrfs_node_blockptr(b, slot);
+ gen = btrfs_node_ptr_generation(b, slot);
+ blocksize = btrfs_level_size(root, level - 1);
+
+ tmp = btrfs_find_tree_block(root, blocknr, blocksize);
+ if (tmp && btrfs_buffer_uptodate(tmp, gen)) {
+ b = tmp;
+ } else {
+ /*
+ * reduce lock contention at high levels
+ * of the btree by dropping locks before
+ * we read.
+ */
+ if (level > 1) {
+ btrfs_release_path(NULL, p);
+ if (tmp)
+ free_extent_buffer(tmp);
+ tmp = read_tree_block(root, blocknr,
+ blocksize, gen);
+ if (tmp)
+ free_extent_buffer(tmp);
+ goto again;
+ } else {
+ if (tmp)
+ free_extent_buffer(tmp);
+ b = read_node_slot(root, b, slot);
+ }