On 12/10/19 4:19 PM, Nikolay Borisov wrote:
On 10.12.19 г. 22:05 ч., Josef Bacik wrote:
On 12/6/19 10:03 AM, Nikolay Borisov wrote:
On 6.12.19 г. 16:37 ч., Josef Bacik wrote:
If we fsync on a subvolume and create a log root for that volume, and
then later delete that subvolume we'll never clean up its log root. Fix
this by making switch_commit_roots free the log for any dropped roots we
encounter.
Signed-off-by: Josef Bacik <josef@xxxxxxxxxxxxxx>
---
fs/btrfs/transaction.c | 22 ++++++++++++----------
1 file changed, 12 insertions(+), 10 deletions(-)
diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index cfc08ef9b876..55d8fd68775a 100644
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -147,13 +147,14 @@ void btrfs_put_transaction(struct
btrfs_transaction *transaction)
}
}
-static noinline void switch_commit_roots(struct btrfs_transaction
*trans)
+static noinline void switch_commit_roots(struct btrfs_trans_handle
*trans)
{
+ struct btrfs_transaction *cur_trans = trans->transaction;
struct btrfs_fs_info *fs_info = trans->fs_info;
struct btrfs_root *root, *tmp;
down_write(&fs_info->commit_root_sem);
- list_for_each_entry_safe(root, tmp, &trans->switch_commits,
+ list_for_each_entry_safe(root, tmp, &cur_trans->switch_commits,
dirty_list) {
list_del_init(&root->dirty_list);
free_extent_buffer(root->commit_root);
@@ -165,16 +166,17 @@ static noinline void switch_commit_roots(struct
btrfs_transaction *trans)
}
/* We can free old roots now. */
- spin_lock(&trans->dropped_roots_lock);
- while (!list_empty(&trans->dropped_roots)) {
- root = list_first_entry(&trans->dropped_roots,
+ spin_lock(&cur_trans->dropped_roots_lock);
+ while (!list_empty(&cur_trans->dropped_roots)) {
+ root = list_first_entry(&cur_trans->dropped_roots,
struct btrfs_root, root_list);
list_del_init(&root->root_list);
- spin_unlock(&trans->dropped_roots_lock);
+ spin_unlock(&cur_trans->dropped_roots_lock);
+ btrfs_free_log(trans, root);
THis patch should really have been this line and converting
switch_commit_roots to taking a trans handle another patch. Otherwise
this is lost in the mechanical refactoring.
We need the trans handle to even call btrfs_free_log, we're just fixing
it so the trans handle can be passed in, making its separate is just
superfluous. Thanks,
Actually no because callees handle the case when trans is not passed
(i.e. walk_log_tree and walk_(up|down)_log_tree. If passing valid
trances changes the call logic then this needs to be explained in the
changelog. And there is currently one caller calling that function
without a trans - btrfs_drop_and_free_fs_root in BTRFS_FS_STATE_ERROR case.
Yeah, it's clear that NULL is used only in the error case. I'm not going to
explain the entirety of how the log tree works in a basic fix for not freeing up
a tree log when we should be doing it. Thanks,
Josef
