From: Yu Kuai <yukuai3@xxxxxxxxxx>
open_table_device() and close_table_device() is protected by
table_devices_lock, hence use it to protect add_disk() and
del_gendisk().
Prepare to track per-add_disk holder relations in dm.
Signed-off-by: Yu Kuai <yukuai3@xxxxxxxxxx>
---
drivers/md/dm.c | 16 ++++++++++++++++
1 file changed, 16 insertions(+)
diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 2917700b1e15..3728b56b364b 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -1952,7 +1952,14 @@ static void cleanup_mapped_device(struct mapped_device *md)
spin_unlock(&_minor_lock);
if (dm_get_md_type(md) != DM_TYPE_NONE) {
dm_sysfs_exit(md);
+
+ /*
+ * Hold lock to make sure del_gendisk() won't concurrent
+ * with open/close_table_device().
+ */
+ mutex_lock(&md->table_devices_lock);
del_gendisk(md->disk);
+ mutex_unlock(&md->table_devices_lock);
}
dm_queue_destroy_crypto_profile(md->queue);
put_disk(md->disk);
@@ -2312,15 +2319,24 @@ int dm_setup_md_queue(struct mapped_device *md, struct dm_table *t)
if (r)
return r;
+ /*
+ * Hold lock to make sure add_disk() and del_gendisk() won't concurrent
+ * with open_table_device() and close_table_device().
+ */
+ mutex_lock(&md->table_devices_lock);
r = add_disk(md->disk);
+ mutex_unlock(&md->table_devices_lock);
if (r)
return r;
r = dm_sysfs_init(md);
if (r) {
+ mutex_lock(&md->table_devices_lock);
del_gendisk(md->disk);
+ mutex_unlock(&md->table_devices_lock);
return r;
}
+
md->type = type;
return 0;
}
--
2.31.1
