block: misc updates to blk_get_queue()

* blk_get_queue() is peculiar in that it returns 0 on success and 1 on failure instead of 0 / -errno or boolean. Update it such that it returns %true on success and %false on failure. * Make sure the caller checks for the return value. * Separate out __blk_get_queue() which doesn't check whether @q is dead and put it in blk.h. This will be used later. This patch doesn't introduce any functional changes. Signed-off-by: Tejun Heo <[email protected]> Signed-off-by: Jens Axboe <[email protected]>
mgowda · Dec 13, 2011 · 09ac46c · 09ac46c
1 parent 6e736be
commit 09ac46c
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Showing 6 changed files with 13 additions and 10 deletions.
diff --git a/block/blk-core.c b/block/blk-core.c
@@ -626,14 +626,14 @@ blk_init_allocated_queue_node(struct request_queue *q, request_fn_proc *rfn,
 }
 EXPORT_SYMBOL(blk_init_allocated_queue_node);
 
-int blk_get_queue(struct request_queue *q)
+bool blk_get_queue(struct request_queue *q)
 {
 	if (likely(!blk_queue_dead(q))) {
-		kobject_get(&q->kobj);
-		return 0;
+		__blk_get_queue(q);
+		return true;
 	}
 
-	return 1;
+	return false;
 }
 EXPORT_SYMBOL(blk_get_queue);
 

diff --git a/block/blk.h b/block/blk.h
@@ -13,6 +13,11 @@ extern struct kmem_cache *blk_requestq_cachep;
 extern struct kobj_type blk_queue_ktype;
 extern struct ida blk_queue_ida;
 
+static inline void __blk_get_queue(struct request_queue *q)
+{
+	kobject_get(&q->kobj);
+}
+
 void init_request_from_bio(struct request *req, struct bio *bio);
 void blk_rq_bio_prep(struct request_queue *q, struct request *rq,
 			struct bio *bio);

diff --git a/block/bsg.c b/block/bsg.c
@@ -769,12 +769,10 @@ static struct bsg_device *bsg_add_device(struct inode *inode,
 					 struct file *file)
 {
 	struct bsg_device *bd;
-	int ret;
 #ifdef BSG_DEBUG
 	unsigned char buf[32];
 #endif
-	ret = blk_get_queue(rq);
-	if (ret)
+	if (!blk_get_queue(rq))
 		return ERR_PTR(-ENXIO);
 
 	bd = bsg_alloc_device();

diff --git a/block/genhd.c b/block/genhd.c
@@ -615,7 +615,7 @@ void add_disk(struct gendisk *disk)
 	 * Take an extra ref on queue which will be put on disk_release()
 	 * so that it sticks around as long as @disk is there.
 	 */
-	WARN_ON_ONCE(blk_get_queue(disk->queue));
+	WARN_ON_ONCE(!blk_get_queue(disk->queue));
 
 	retval = sysfs_create_link(&disk_to_dev(disk)->kobj, &bdi->dev->kobj,
 				   "bdi");

diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c
@@ -297,7 +297,7 @@ static struct scsi_device *scsi_alloc_sdev(struct scsi_target *starget,
 		kfree(sdev);
 		goto out;
 	}
-	blk_get_queue(sdev->request_queue);
+	WARN_ON_ONCE(!blk_get_queue(sdev->request_queue));
 	sdev->request_queue->queuedata = sdev;
 	scsi_adjust_queue_depth(sdev, 0, sdev->host->cmd_per_lun);
 

diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
@@ -865,7 +865,7 @@ extern int blk_rq_map_sg(struct request_queue *, struct request *, struct scatte
 extern void blk_dump_rq_flags(struct request *, char *);
 extern long nr_blockdev_pages(void);
 
-int blk_get_queue(struct request_queue *);
+bool __must_check blk_get_queue(struct request_queue *);
 struct request_queue *blk_alloc_queue(gfp_t);
 struct request_queue *blk_alloc_queue_node(gfp_t, int);
 extern void blk_put_queue(struct request_queue *);