From 8333b0a8375d9d2f2fa2141c418a895fcf1a8c04 Mon Sep 17 00:00:00 2001 From: Josef Bacik Date: Wed, 17 Jul 2013 19:30:20 -0400 Subject: Btrfs: re-add root to dead root list if we stop dropping it commit d29a9f629e009c9b90e5859bce581070fd6247fc upstream. If we stop dropping a root for whatever reason we need to add it back to the dead root list so that we will re-start the dropping next transaction commit. The other case this happens is if we recover a drop because we will add a root without adding it to the fs radix tree, so we can leak it's root and commit root extent buffer, adding this to the dead root list makes this cleanup happen. Thanks, Reported-by: Alex Lyakas Signed-off-by: Josef Bacik [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings --- fs/btrfs/extent-tree.c | 11 +++++++++++ 1 file changed, 11 insertions(+) (limited to 'fs/btrfs') diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index 78179a3..49eefdb 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -6560,6 +6560,7 @@ void btrfs_drop_snapshot(struct btrfs_root *root, int err = 0; int ret; int level; + bool root_dropped = false; path = btrfs_alloc_path(); if (!path) { @@ -6709,11 +6710,21 @@ void btrfs_drop_snapshot(struct btrfs_root *root, free_extent_buffer(root->commit_root); kfree(root); } + root_dropped = true; out_free: btrfs_end_transaction_throttle(trans, tree_root); kfree(wc); btrfs_free_path(path); out: + /* + * So if we need to stop dropping the snapshot for whatever reason we + * need to make sure to add it back to the dead root list so that we + * keep trying to do the work later. This also cleans up roots if we + * don't have it in the radix (like when we recover after a power fail + * or unmount) so we don't leak memory. + */ + if (root_dropped == false) + btrfs_add_dead_root(root); if (err) btrfs_std_error(root->fs_info, err); return; -- cgit v1.1