dm: allow targets to return output from messages they are sent
Could be useful for a target to return stats or other information.
If a target does DMEMIT() anything to @result from its .message method
then it must return 1 to the caller.
Signed-off-By: Mike Snitzer <snitzer@redhat.com>
diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c
index 8168f73..dd9b533 100644
--- a/drivers/md/dm-crypt.c
+++ b/drivers/md/dm-crypt.c
@@ -2942,7 +2942,8 @@ static void crypt_resume(struct dm_target *ti)
* key set <key>
* key wipe
*/
-static int crypt_message(struct dm_target *ti, unsigned argc, char **argv)
+static int crypt_message(struct dm_target *ti, unsigned argc, char **argv,
+ char *result, unsigned maxlen)
{
struct crypt_config *cc = ti->private;
int key_size, ret = -EINVAL;