@@ -1023,7 +1023,6 @@ static int update_cowonly_root(struct btrfs_trans_handle *trans,
u64 old_root_bytenr;
u64 old_root_used;
struct btrfs_root *tree_root = root->fs_info->tree_root;
- bool extent_root = (root->objectid == BTRFS_EXTENT_TREE_OBJECTID);
old_root_used = btrfs_root_used(&root->root_item);
btrfs_write_dirty_block_groups(trans, root);
@@ -1031,9 +1030,7 @@ static int update_cowonly_root(struct btrfs_trans_handle *trans,
while (1) {
old_root_bytenr = btrfs_root_bytenr(&root->root_item);
if (old_root_bytenr == root->node->start &&
- old_root_used == btrfs_root_used(&root->root_item) &&
- (!extent_root ||
- list_empty(&trans->transaction->dirty_bgs)))
+ old_root_used == btrfs_root_used(&root->root_item))
break;
btrfs_set_root_node(&root->root_item, root->node);
@@ -1044,17 +1041,6 @@ static int update_cowonly_root(struct btrfs_trans_handle *trans,
return ret;
old_root_used = btrfs_root_used(&root->root_item);
- if (extent_root) {
- ret = btrfs_write_dirty_block_groups(trans, root);
- if (ret)
- return ret;
- }
- ret = btrfs_run_delayed_refs(trans, root, (unsigned long)-1);
- if (ret)
- return ret;
- ret = btrfs_run_delayed_refs(trans, root, (unsigned long)-1);
- if (ret)
- return ret;
}
return 0;
@@ -1115,6 +1101,14 @@ static noinline int commit_cowonly_roots(struct btrfs_trans_handle *trans,
ret = update_cowonly_root(trans, root);
if (ret)
return ret;
+ if (list_empty(&fs_info->dirty_cowonly_roots)) {
+ ret = btrfs_write_dirty_block_groups(trans, root);
+ if (ret)
+ return ret;
+ }
+ ret = btrfs_run_delayed_refs(trans, root, (unsigned long)-1);
+ if (ret)
+ return ret;
}
list_add_tail(&fs_info->extent_root->dirty_list,
Dave could hit this assert consistently running btrfs/078. This is because when we update the block groups we could truncate the free space, which would try to delete the csums for that range and dirty the csum root. For this to happen we have to have already written out the csum root so it's kind of hard to hit this case. This patch fixes this by changing the logic to only write the dirty block groups if the dirty_cowonly_roots list is empty. This will get us the same effect as before since we add the extent root last, and will cover the case that we dirty some other root again but not the extent root. Thanks, Reported-by: David Sterba <dsterba@suse.cz> Signed-off-by: Josef Bacik <jbacik@fb.com> --- V1->V2: moved the logic to the loop in commit_cowonly_roots so we can be sure that we're always running delayed refs and always writing the drity block groups. fs/btrfs/transaction.c | 24 +++++++++--------------- 1 file changed, 9 insertions(+), 15 deletions(-)