Commit e9193da0 authored by Jens Axboe's avatar Jens Axboe
Browse files

Merge branch 'stable/for-jens-4.13' of... 

Merge branch 'stable/for-jens-4.13' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen into for-linus

Pull xen-blkfront fixes from Konrad for 4.13.
parents 7a362ea9 bd912ef3

drivers/block/xen-blkfront.c

+12 −9
Original line number Diff line number Diff line
@@ -708,6 +708,7 @@ static int blkif_queue_rw_req(struct request *req, struct blkfront_ring_info *ri 
	 * existing persistent grants, or if we have to get new grants,

	 * as there are not sufficiently many free.

	 */

	bool new_persistent_gnts = false;

	struct scatterlist *sg;

	int num_sg, max_grefs, num_grant;
@@ -719,19 +720,21 @@ static int blkif_queue_rw_req(struct request *req, struct blkfront_ring_info *ri 
		 */

		max_grefs += INDIRECT_GREFS(max_grefs);



	/*

	 * We have to reserve 'max_grefs' grants because persistent

	 * grants are shared by all rings.

	 */

	if (max_grefs > 0)

		if (gnttab_alloc_grant_references(max_grefs, &setup.gref_head) < 0) {

	/* Check if we have enough persistent grants to allocate a requests */

	if (rinfo->persistent_gnts_c < max_grefs) {

		new_persistent_gnts = true;



		if (gnttab_alloc_grant_references(

		    max_grefs - rinfo->persistent_gnts_c,

		    &setup.gref_head) < 0) {

			gnttab_request_free_callback(

				&rinfo->callback,

				blkif_restart_queue_callback,

				rinfo,

				max_grefs);

				max_grefs - rinfo->persistent_gnts_c);

			return 1;

		}

	}



	/* Fill out a communications ring structure. */

	id = blkif_ring_get_request(rinfo, req, &ring_req);
@@ -832,7 +835,7 @@ static int blkif_queue_rw_req(struct request *req, struct blkfront_ring_info *ri 
	if (unlikely(require_extra_req))

		rinfo->shadow[extra_id].req = *extra_ring_req;



	if (max_grefs > 0)

	if (new_persistent_gnts)

		gnttab_free_grant_references(setup.gref_head);



	return 0;
@@ -906,8 +909,8 @@ static blk_status_t blkif_queue_rq(struct blk_mq_hw_ctx *hctx, 
	return BLK_STS_IOERR;



out_busy:

	spin_unlock_irqrestore(&rinfo->ring_lock, flags);

	blk_mq_stop_hw_queue(hctx);

	spin_unlock_irqrestore(&rinfo->ring_lock, flags);

	return BLK_STS_RESOURCE;

}