Btrfs: Add support for multiple devices per filesystem

Signed-off-by: Chris Mason <chris.mason@oracle.com>

1 files changed, 37 insertions, 1 deletions

diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index ef8809c1e69c..70b6ddfe15a1 100644
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -70,6 +70,14 @@ void btrfs_release_path(struct btrfs_root *root, struct btrfs_path *p)
         memset(p, 0, sizeof(*p));
 }
 
+static void add_root_to_dirty_list(struct btrfs_root *root)
+{
+        if (root->track_dirty && list_empty(&root->dirty_list)) {
+                list_add(&root->dirty_list,
+                         &root->fs_info->dirty_cowonly_roots);
+        }
+}
+
 int btrfs_copy_root(struct btrfs_trans_handle *trans,
                       struct btrfs_root *root,
                       struct extent_buffer *buf,
@@ -196,6 +204,7 @@ int __btrfs_cow_block(struct btrfs_trans_handle *trans,
                                           root_gen, 0, 0, 1);
                 }
                 free_extent_buffer(buf);
+                add_root_to_dirty_list(root);
         } else {
                 root_gen = btrfs_header_generation(parent);
                 btrfs_set_node_blockptr(parent, parent_slot,
@@ -241,7 +250,7 @@ int btrfs_cow_block(struct btrfs_trans_handle *trans,
                 return 0;
         }
 
-        search_start = buf->start & ~((u64)BTRFS_BLOCK_GROUP_SIZE - 1);
+        search_start = buf->start & ~((u64)(1024 * 1024 * 1024) - 1);
         ret = __btrfs_cow_block(trans, root, buf, parent,
                                  parent_slot, cow_ret, search_start, 0);
         return ret;
@@ -724,6 +733,7 @@ static int balance_level(struct btrfs_trans_handle *trans,
                 BUG_ON(ret);
 
                 root->node = child;
+                add_root_to_dirty_list(root);
                 path->nodes[level] = NULL;
                 clean_tree_block(trans, root, mid);
                 wait_on_tree_block_writeback(root, mid);
@@ -1369,6 +1379,7 @@ static int noinline insert_new_root(struct btrfs_trans_handle *trans,
         /* the super has an extra ref to root->node */
         free_extent_buffer(root->node);
         root->node = c;
+        add_root_to_dirty_list(root);
         extent_buffer_get(c);
         path->nodes[level] = c;
         path->slots[level] = 0;
@@ -2777,3 +2788,28 @@ int btrfs_next_leaf(struct btrfs_root *root, struct btrfs_path *path)
         }
         return 0;
 }
+
+int btrfs_previous_item(struct btrfs_root *root,
+                        struct btrfs_path *path, u64 min_objectid,
+                        int type)
+{
+        struct btrfs_key found_key;
+        struct extent_buffer *leaf;
+        int ret;
+
+        while(1) {
+                if (path->slots[0] == 0) {
+                        ret = btrfs_prev_leaf(root, path);
+                        if (ret != 0)
+                                return ret;
+                } else {
+                        path->slots[0]--;
+                }
+                leaf = path->nodes[0];
+                btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
+                if (found_key.type == type)
+                        return 0;
+        }
+        return 1;
+}
+