diff options
authorAleksa Sarai <asarai@suse.de>2017-07-04 21:49:06 +1000
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2017-09-13 14:09:46 -0700
commit693b7f62a439ec11a671eee76cad2e7078dad913 (patch)
parentf4596ead66a74ca566d1aa17dfa7e42bba97b5f5 (diff)
btrfs: resume qgroup rescan on rw remount
commit 6c6b5a39c4bf3dbd8cf629c9f5450e983c19dbb9 upstream. Several distributions mount the "proper root" as ro during initrd and then remount it as rw before pivot_root(2). Thus, if a rescan had been aborted by a previous shutdown, the rescan would never be resumed. This issue would manifest itself as several btrfs ioctl(2)s causing the entire machine to hang when btrfs_qgroup_wait_for_completion was hit (due to the fs_info->qgroup_rescan_running flag being set but the rescan itself not being resumed). Notably, Docker's btrfs storage driver makes regular use of BTRFS_QUOTA_CTL_DISABLE and BTRFS_IOC_QUOTA_RESCAN_WAIT (causing this problem to be manifested on boot for some machines). Cc: Jeff Mahoney <jeffm@suse.com> Fixes: b382a324b60f ("Btrfs: fix qgroup rescan resume on mount") Signed-off-by: Aleksa Sarai <asarai@suse.de> Reviewed-by: Nikolay Borisov <nborisov@suse.com> Tested-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
1 files changed, 2 insertions, 0 deletions
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 5d34a062ca4f..3bd2233737ac 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -1727,6 +1727,8 @@ static int btrfs_remount(struct super_block *sb, int *flags, char *data)
goto restore;
+ btrfs_qgroup_rescan_resume(fs_info);
if (!fs_info->uuid_root) {
btrfs_info(fs_info, "creating UUID tree");
ret = btrfs_create_uuid_tree(fs_info);