Btrfs: Add support for multiple devices per filesystem

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

1 files changed, 34 insertions, 16 deletions

diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index e9a0983897f3..5e9f69244f9f 100644
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -198,29 +198,42 @@ int btrfs_write_and_wait_transaction(struct btrfs_trans_handle *trans,
         return werr;
 }
 
-int btrfs_commit_tree_roots(struct btrfs_trans_handle *trans,
-                            struct btrfs_root *root)
+static int update_cowonly_root(struct btrfs_trans_handle *trans,
+                               struct btrfs_root *root)
 {
         int ret;
-        u64 old_extent_block;
-        struct btrfs_fs_info *fs_info = root->fs_info;
-        struct btrfs_root *tree_root = fs_info->tree_root;
-        struct btrfs_root *extent_root = fs_info->extent_root;
+        u64 old_root_bytenr;
+        struct btrfs_root *tree_root = root->fs_info->tree_root;
 
-        btrfs_write_dirty_block_groups(trans, extent_root);
+        btrfs_write_dirty_block_groups(trans, root);
         while(1) {
-                old_extent_block = btrfs_root_bytenr(&extent_root->root_item);
-                if (old_extent_block == extent_root->node->start)
+                old_root_bytenr = btrfs_root_bytenr(&root->root_item);
+                if (old_root_bytenr == root->node->start)
                         break;
-                btrfs_set_root_bytenr(&extent_root->root_item,
-                                      extent_root->node->start);
-                btrfs_set_root_level(&extent_root->root_item,
-                                     btrfs_header_level(extent_root->node));
+                btrfs_set_root_bytenr(&root->root_item,
+                                       root->node->start);
+                btrfs_set_root_level(&root->root_item,
+                                     btrfs_header_level(root->node));
                 ret = btrfs_update_root(trans, tree_root,
-                                        &extent_root->root_key,
-                                        &extent_root->root_item);
+                                        &root->root_key,
+                                        &root->root_item);
                 BUG_ON(ret);
-                btrfs_write_dirty_block_groups(trans, extent_root);
+                btrfs_write_dirty_block_groups(trans, root);
+        }
+        return 0;
+}
+
+int btrfs_commit_tree_roots(struct btrfs_trans_handle *trans,
+                            struct btrfs_root *root)
+{
+        struct btrfs_fs_info *fs_info = root->fs_info;
+        struct list_head *next;
+
+        while(!list_empty(&fs_info->dirty_cowonly_roots)) {
+                next = fs_info->dirty_cowonly_roots.next;
+                list_del_init(next);
+                root = list_entry(next, struct btrfs_root, dirty_list);
+                update_cowonly_root(trans, root);
         }
         return 0;
 }
@@ -616,6 +629,7 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
         unsigned long timeout = 1;
         struct btrfs_transaction *cur_trans;
         struct btrfs_transaction *prev_trans = NULL;
+        struct btrfs_root *chunk_root = root->fs_info->chunk_root;
         struct list_head dirty_fs_roots;
         struct extent_io_tree *pinned_copy;
         DEFINE_WAIT(wait);
@@ -714,6 +728,10 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
         btrfs_set_super_root_level(&root->fs_info->super_copy,
                            btrfs_header_level(root->fs_info->tree_root->node));
 
+        btrfs_set_super_chunk_root(&root->fs_info->super_copy,
+                                   chunk_root->node->start);
+        btrfs_set_super_chunk_root_level(&root->fs_info->super_copy,
+                                         btrfs_header_level(chunk_root->node));
         write_extent_buffer(root->fs_info->sb_buffer,
                             &root->fs_info->super_copy, 0,
                             sizeof(root->fs_info->super_copy));