md: md_stop_writes requires mddev_lock.

As md_stop_writes manipulates the sync_thread and calls md_update_sb,
it need to be called with mddev_lock held.

In all internal cases it is, but the symbol is exported for dm-raid to
call and in that case the lock won't be help.
Do make an exported version which takes the lock, and an internal
version which does not.

Signed-off-by: NeilBrown <neilb@suse.de>
This commit is contained in:
NeilBrown 2011-01-14 09:14:33 +11:00
parent 43c73ca43b
commit defad61a5b

View file

@ -4704,7 +4704,7 @@ static void md_clean(mddev_t *mddev)
mddev->plug = NULL;
}
void md_stop_writes(mddev_t *mddev)
static void __md_stop_writes(mddev_t *mddev)
{
if (mddev->sync_thread) {
set_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
@ -4724,6 +4724,13 @@ void md_stop_writes(mddev_t *mddev)
md_update_sb(mddev, 1);
}
}
void md_stop_writes(mddev_t *mddev)
{
mddev_lock(mddev);
__md_stop_writes(mddev);
mddev_unlock(mddev);
}
EXPORT_SYMBOL_GPL(md_stop_writes);
void md_stop(mddev_t *mddev)
@ -4748,7 +4755,7 @@ static int md_set_readonly(mddev_t *mddev, int is_open)
goto out;
}
if (mddev->pers) {
md_stop_writes(mddev);
__md_stop_writes(mddev);
err = -ENXIO;
if (mddev->ro==1)
@ -4785,7 +4792,7 @@ static int do_md_stop(mddev_t * mddev, int mode, int is_open)
if (mddev->ro)
set_disk_ro(disk, 0);
md_stop_writes(mddev);
__md_stop_writes(mddev);
md_stop(mddev);
mddev->queue->merge_bvec_fn = NULL;
mddev->queue->unplug_fn = NULL;