Btrfs: Metadata ENOSPC handling for balance
This patch adds metadata ENOSPC handling for the balance code.
It is consisted by following major changes:
1. Avoid COW tree leave in the phrase of merging tree.
2. Handle interaction with snapshot creation.
3. make the backref cache can live across transactions.
Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index cfe7f58..c346d32 100644
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -853,6 +853,7 @@
goto fail;
}
+ btrfs_reloc_pre_snapshot(trans, pending, &to_reserve);
btrfs_orphan_pre_snapshot(trans, pending, &to_reserve);
if (to_reserve > 0) {
@@ -924,6 +925,7 @@
pending->snap = btrfs_read_fs_root_no_name(root->fs_info, &key);
BUG_ON(IS_ERR(pending->snap));
+ btrfs_reloc_post_snapshot(trans, pending);
btrfs_orphan_post_snapshot(trans, pending);
fail:
kfree(new_root_item);
@@ -1213,9 +1215,9 @@
if (btrfs_header_backref_rev(root->node) <
BTRFS_MIXED_BACKREF_REV)
- btrfs_drop_snapshot(root, 0);
+ btrfs_drop_snapshot(root, NULL, 0);
else
- btrfs_drop_snapshot(root, 1);
+ btrfs_drop_snapshot(root, NULL, 1);
}
return 0;
}