usb: option: add Alcatel L800MA

[cascardo/linux.git] / drivers / block / virtio_blk.c

diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c
index b1cb3f4..6d8a87f 100644 (file)
--- a/drivers/block/virtio_blk.c
+++ b/drivers/block/virtio_blk.c
@@ -158,6 +158,7 @@ static int virtio_queue_rq(struct blk_mq_hw_ctx *hctx, struct request *req)
        unsigned long flags;
        unsigned int num;
        const bool last = (req->cmd_flags & REQ_END) != 0;
+       int err;
 
        BUG_ON(req->nr_phys_segments + 2 > vblk->sg_elems);
 
@@ -198,11 +199,16 @@ static int virtio_queue_rq(struct blk_mq_hw_ctx *hctx, struct request *req)
        }
 
        spin_lock_irqsave(&vblk->vq_lock, flags);
-       if (__virtblk_add_req(vblk->vq, vbr, vbr->sg, num) < 0) {
+       err = __virtblk_add_req(vblk->vq, vbr, vbr->sg, num);
+       if (err) {
                virtqueue_kick(vblk->vq);
                spin_unlock_irqrestore(&vblk->vq_lock, flags);
                blk_mq_stop_hw_queue(hctx);
-               return BLK_MQ_RQ_QUEUE_BUSY;
+               /* Out of mem doesn't actually happen, since we fall back
+                * to direct descriptors */
+               if (err == -ENOMEM || err == -ENOSPC)
+                       return BLK_MQ_RQ_QUEUE_BUSY;
+               return BLK_MQ_RQ_QUEUE_ERROR;
        }
 
        if (last)
@@ -485,18 +491,20 @@ static struct blk_mq_ops virtio_mq_ops = {
 static struct blk_mq_reg virtio_mq_reg = {
        .ops            = &virtio_mq_ops,
        .nr_hw_queues   = 1,
-       .queue_depth    = 64,
+       .queue_depth    = 0, /* Set in virtblk_probe */
        .numa_node      = NUMA_NO_NODE,
        .flags          = BLK_MQ_F_SHOULD_MERGE,
 };
+module_param_named(queue_depth, virtio_mq_reg.queue_depth, uint, 0444);
 
-static void virtblk_init_vbr(void *data, struct blk_mq_hw_ctx *hctx,
+static int virtblk_init_vbr(void *data, struct blk_mq_hw_ctx *hctx,
                             struct request *rq, unsigned int nr)
 {
        struct virtio_blk *vblk = data;
        struct virtblk_req *vbr = rq->special;
 
        sg_init_table(vbr->sg, vblk->sg_elems);
+       return 0;
 }
 
 static int virtblk_probe(struct virtio_device *vdev)
@@ -552,6 +560,13 @@ static int virtblk_probe(struct virtio_device *vdev)
                goto out_free_vq;
        }
 
+       /* Default queue sizing is to fill the ring. */
+       if (!virtio_mq_reg.queue_depth) {
+               virtio_mq_reg.queue_depth = vblk->vq->num_free;
+               /* ... but without indirect descs, we use 2 descs per req */
+               if (!virtio_has_feature(vdev, VIRTIO_RING_F_INDIRECT_DESC))
+                       virtio_mq_reg.queue_depth /= 2;
+       }
        virtio_mq_reg.cmd_size =
                sizeof(struct virtblk_req) +
                sizeof(struct scatterlist) * sg_elems;