block: simplify blk_init_allocated_queue

Return an errno value instead of the passed in queue so that the callers
don't have to keep track of two queues, and move the assignment of the
request_fn and lock to the caller as passing them as argument doesn't
simplify anything.  While we're at it also remove two pointless NULL
assignments, given that the request structure is zeroed on allocation.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

diff --git a/block/blk-core.c b/block/blk-core.c
index 4cad535592c353f9a76b1c5dde2f978ad1818ed7..09819d24d385be9ffbc19a23de47883c7055e84d 100644 (file)
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -823,15 +823,19 @@ EXPORT_SYMBOL(blk_init_queue);
 struct request_queue *
 blk_init_queue_node(request_fn_proc *rfn, spinlock_t *lock, int node_id)
 {
-       struct request_queue *uninit_q, *q;
+       struct request_queue *q;
 
-       uninit_q = blk_alloc_queue_node(GFP_KERNEL, node_id);
-       if (!uninit_q)
+       q = blk_alloc_queue_node(GFP_KERNEL, node_id);
+       if (!q)
                return NULL;
 
-       q = blk_init_allocated_queue(uninit_q, rfn, lock);
-       if (!q)
-               blk_cleanup_queue(uninit_q);
+       q->request_fn = rfn;
+       if (lock)
+               q->queue_lock = lock;
+       if (blk_init_allocated_queue(q) < 0) {
+               blk_cleanup_queue(q);
+               return NULL;
+       }
 
        return q;
 }
@@ -839,30 +843,19 @@ EXPORT_SYMBOL(blk_init_queue_node);
 
 static blk_qc_t blk_queue_bio(struct request_queue *q, struct bio *bio);
 
-struct request_queue *
-blk_init_allocated_queue(struct request_queue *q, request_fn_proc *rfn,
-                        spinlock_t *lock)
-{
-       if (!q)
-               return NULL;
 
+int blk_init_allocated_queue(struct request_queue *q)
+{
        q->fq = blk_alloc_flush_queue(q, NUMA_NO_NODE, 0);
        if (!q->fq)
-               return NULL;
+               return -ENOMEM;
 
        if (blk_init_rl(&q->root_rl, q, GFP_KERNEL))
                goto fail;
 
        INIT_WORK(&q->timeout_work, blk_timeout_work);
-       q->request_fn           = rfn;
-       q->prep_rq_fn           = NULL;
-       q->unprep_rq_fn         = NULL;
        q->queue_flags          |= QUEUE_FLAG_DEFAULT;
 
-       /* Override internal queue lock with supplied lock pointer */
-       if (lock)
-               q->queue_lock           = lock;
-
        /*
         * This also sets hw/phys segments, boundary and size
         */
@@ -880,13 +873,12 @@ blk_init_allocated_queue(struct request_queue *q, request_fn_proc *rfn,
        }
 
        mutex_unlock(&q->sysfs_lock);
-
-       return q;
+       return 0;
 
 fail:
        blk_free_flush_queue(q->fq);
        wbt_exit(q);
-       return NULL;
+       return -ENOMEM;
 }
 EXPORT_SYMBOL(blk_init_allocated_queue);
 

diff --git a/drivers/md/dm-rq.c b/drivers/md/dm-rq.c
index 9d7275fb541ad422b171cbe0ee43335e3e1efc27..93f6e9f1ebe28e849a94faf4ef89c0fc2a076592 100644 (file)
--- a/drivers/md/dm-rq.c
+++ b/drivers/md/dm-rq.c
@@ -823,7 +823,8 @@ static void dm_old_request_fn(struct request_queue *q)
 int dm_old_init_request_queue(struct mapped_device *md)
 {
        /* Fully initialize the queue */
-       if (!blk_init_allocated_queue(md->queue, dm_old_request_fn, NULL))
+       md->queue->request_fn = dm_old_request_fn;
+       if (blk_init_allocated_queue(md->queue) < 0)
                return -EINVAL;
 
        /* disable dm_old_request_fn's merge heuristic by default */

diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 05675b1dfd204ca6d475774b9ee13dbed30cb739..6b1efc5760ea52bbdcddd1badf6e2740566891f1 100644 (file)
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -1137,8 +1137,7 @@ extern void blk_unprep_request(struct request *);
 extern struct request_queue *blk_init_queue_node(request_fn_proc *rfn,
                                        spinlock_t *lock, int node_id);
 extern struct request_queue *blk_init_queue(request_fn_proc *, spinlock_t *);
-extern struct request_queue *blk_init_allocated_queue(struct request_queue *,
-                                                     request_fn_proc *, spinlock_t *);
+extern int blk_init_allocated_queue(struct request_queue *);
 extern void blk_cleanup_queue(struct request_queue *);
 extern void blk_queue_make_request(struct request_queue *, make_request_fn *);
 extern void blk_queue_bounce_limit(struct request_queue *, u64);