From b382a324b60f4923e9fc8e11f023e4f493c51318 Mon Sep 17 00:00:00 2001 From: Jan Schmidt Date: Tue, 28 May 2013 15:47:24 +0000 Subject: Btrfs: fix qgroup rescan resume on mount When called during mount, we cannot start the rescan worker thread until open_ctree is done. This commit restuctures the qgroup rescan internals to enable a clean deferral of the rescan resume operation. First of all, the struct qgroup_rescan is removed, saving us a malloc and some initialization synchronizations problems. Its only element (the worker struct) now lives within fs_info just as the rest of the rescan code. Then setting up a rescan worker is split into several reusable stages. Currently we have three different rescan startup scenarios: (A) rescan ioctl (B) rescan resume by mount (C) rescan by quota enable Each case needs its own combination of the four following steps: (1) set the progress [A, C: zero; B: state of umount] (2) commit the transaction [A] (3) set the counters [A, C: zero; B: state of umount] (4) start worker [A, B, C] qgroup_rescan_init does step (1). There's no extra function added to commit a transaction, we've got that already. qgroup_rescan_zero_tracking does step (3). Step (4) is nothing more than a call to the generic btrfs_queue_worker. We also get rid of a double check for the rescan progress during btrfs_qgroup_account_ref, which is no longer required due to having step 2 from the list above. As a side effect, this commit prepares to move the rescan start code from btrfs_run_qgroups (which is run during commit) to a less time critical section. Signed-off-by: Jan Schmidt Signed-off-by: Josef Bacik --- fs/btrfs/ctree.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'fs/btrfs/ctree.h') diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index a07b8c0a260d..80ab1a6f4fe3 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -1609,6 +1609,7 @@ struct btrfs_fs_info { struct btrfs_key qgroup_rescan_progress; struct btrfs_workers qgroup_rescan_workers; struct completion qgroup_rescan_completion; + struct btrfs_work qgroup_rescan_work; /* filesystem state */ unsigned long fs_state; @@ -3858,6 +3859,7 @@ int btrfs_quota_enable(struct btrfs_trans_handle *trans, int btrfs_quota_disable(struct btrfs_trans_handle *trans, struct btrfs_fs_info *fs_info); int btrfs_qgroup_rescan(struct btrfs_fs_info *fs_info); +void btrfs_qgroup_rescan_resume(struct btrfs_fs_info *fs_info); int btrfs_qgroup_wait_for_completion(struct btrfs_fs_info *fs_info); int btrfs_add_qgroup_relation(struct btrfs_trans_handle *trans, struct btrfs_fs_info *fs_info, u64 src, u64 dst); -- cgit v1.2.3