blk-cgroup: pass a gendisk to blkcg_init_queue and blkcg_exit_queue

Pass the gendisk to blkcg_init_disk and blkcg_exit_disk as part of moving
the blk-cgroup infrastructure to be gendisk based.  Also remove the
rather pointless kerneldoc comments for these internal functions with a
single caller each.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Andreas Herrmann <aherrmann@suse.de>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20220921180501.1539876-7-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

block/blk-cgroup.c

@@ -1230,18 +1230,9 @@ static int blkcg_css_online(struct cgroup_subsys_state *css)
 	return 0;
 }
 
-/**
- * blkcg_init_queue - initialize blkcg part of request queue
- * @q: request_queue to initialize
- *
- * Called from blk_alloc_queue(). Responsible for initializing blkcg
- * part of new request_queue @q.
- *
- * RETURNS:
- * 0 on success, -errno on failure.
- */
-int blkcg_init_queue(struct request_queue *q)
+int blkcg_init_disk(struct gendisk *disk)
 {
+	struct request_queue *q = disk->queue;
 	struct blkcg_gq *new_blkg, *blkg;
 	bool preloaded;
 	int ret;
@@ -1294,16 +1285,10 @@ int blkcg_init_queue(struct request_queue *q)
 	return PTR_ERR(blkg);
 }
 
-/**
- * blkcg_exit_queue - exit and release blkcg part of request_queue
- * @q: request_queue being released
- *
- * Called from blk_exit_queue().  Responsible for exiting blkcg part.
- */
-void blkcg_exit_queue(struct request_queue *q)
+void blkcg_exit_disk(struct gendisk *disk)
 {
-	blkg_destroy_all(q);
-	blk_throtl_exit(q);
+	blkg_destroy_all(disk->queue);
+	blk_throtl_exit(disk->queue);
 }
 
 static void blkcg_bind(struct cgroup_subsys_state *root_css)

block/blk-cgroup.h

@@ -178,8 +178,8 @@ struct blkcg_policy {
 extern struct blkcg blkcg_root;
 extern bool blkcg_debug_stats;
 
-int blkcg_init_queue(struct request_queue *q);
-void blkcg_exit_queue(struct request_queue *q);
+int blkcg_init_disk(struct gendisk *disk);
+void blkcg_exit_disk(struct gendisk *disk);
 
 /* Blkio controller policy registration */
 int blkcg_policy_register(struct blkcg_policy *pol);
@@ -481,8 +481,8 @@ struct blkcg {
 };
 
 static inline struct blkcg_gq *blkg_lookup(struct blkcg *blkcg, void *key) { return NULL; }
-static inline int blkcg_init_queue(struct request_queue *q) { return 0; }
-static inline void blkcg_exit_queue(struct request_queue *q) { }
+static inline int blkcg_init_disk(struct gendisk *disk) { return 0; }
+static inline void blkcg_exit_disk(struct gendisk *disk) { }
 static inline int blkcg_policy_register(struct blkcg_policy *pol) { return 0; }
 static inline void blkcg_policy_unregister(struct blkcg_policy *pol) { }
 static inline int blkcg_activate_policy(struct request_queue *q,

block/genhd.c

@@ -1150,7 +1150,8 @@ static void disk_release(struct device *dev)
 	    !test_bit(GD_ADDED, &disk->state))
 		blk_mq_exit_queue(disk->queue);
 
-	blkcg_exit_queue(disk->queue);
+	blkcg_exit_disk(disk);
+
 	bioset_exit(&disk->bio_split);
 
 	disk_release_events(disk);
@@ -1363,7 +1364,7 @@ struct gendisk *__alloc_disk_node(struct request_queue *q, int node_id,
 	if (xa_insert(&disk->part_tbl, 0, disk->part0, GFP_KERNEL))
 		goto out_destroy_part_tbl;
 
-	if (blkcg_init_queue(q))
+	if (blkcg_init_disk(disk))
 		goto out_erase_part0;
 
 	rand_initialize_disk(disk);