block: move blk_queue_registered() check into elv_iosched_store()

Move blk_queue_registered() check into elv_iosched_store() and prepare
for using elevator_change() for covering any kind of elevator change in
adding/deleting disk and updating nr_hw_queue.

Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Nilay Shroff <nilay@linux.ibm.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20250505141805.2751237-13-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/block/elevator.c b/block/elevator.c
index 766deaf342146231da1f94d66306922066bdfe42..4e58379c4d880f6c5869f397235cbcbdae8f99fe 100644 (file)
--- a/block/elevator.c
+++ b/block/elevator.c
@@ -676,10 +676,6 @@ out_unfreeze:
  */
 static int elevator_change(struct request_queue *q, const char *elevator_name)
 {
-       /* Make sure queue is not in the middle of being removed */
-       if (!blk_queue_registered(q))
-               return -ENOENT;
-
        if (q->elevator && elevator_match(q->elevator->type, elevator_name))
                return 0;
 
@@ -708,6 +704,10 @@ ssize_t elv_iosched_store(struct gendisk *disk, const char *buf,
        struct request_queue *q = disk->queue;
        struct blk_mq_tag_set *set = q->tag_set;
 
+       /* Make sure queue is not in the middle of being removed */
+       if (!blk_queue_registered(q))
+               return -ENOENT;
+
        /*
         * If the attribute needs to load a module, do it before freezing the
         * queue to ensure that the module file can be read when the request