diff options
| -rw-r--r-- | drivers/block/virtio_blk.c | 114 |
1 files changed, 98 insertions, 16 deletions
diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c index ad5f9ce8f3f9..6fc7850c2b0a 100644 --- a/drivers/block/virtio_blk.c +++ b/drivers/block/virtio_blk.c @@ -101,8 +101,7 @@ static inline blk_status_t virtblk_result(struct virtblk_req *vbr) } } -static int virtblk_add_req(struct virtqueue *vq, struct virtblk_req *vbr, - struct scatterlist *data_sg, bool have_data) +static int virtblk_add_req(struct virtqueue *vq, struct virtblk_req *vbr) { struct scatterlist hdr, status, *sgs[3]; unsigned int num_out = 0, num_in = 0; @@ -110,11 +109,11 @@ static int virtblk_add_req(struct virtqueue *vq, struct virtblk_req *vbr, sg_init_one(&hdr, &vbr->out_hdr, sizeof(vbr->out_hdr)); sgs[num_out++] = &hdr; - if (have_data) { + if (vbr->sg_table.nents) { if (vbr->out_hdr.type & cpu_to_virtio32(vq->vdev, VIRTIO_BLK_T_OUT)) - sgs[num_out++] = data_sg; + sgs[num_out++] = vbr->sg_table.sgl; else - sgs[num_out + num_in++] = data_sg; + sgs[num_out + num_in++] = vbr->sg_table.sgl; } sg_init_one(&status, &vbr->status, sizeof(vbr->status)); @@ -304,6 +303,28 @@ static void virtio_commit_rqs(struct blk_mq_hw_ctx *hctx) virtqueue_notify(vq->vq); } +static blk_status_t virtblk_prep_rq(struct blk_mq_hw_ctx *hctx, + struct virtio_blk *vblk, + struct request *req, + struct virtblk_req *vbr) +{ + blk_status_t status; + + status = virtblk_setup_cmd(vblk->vdev, req, vbr); + if (unlikely(status)) + return status; + + blk_mq_start_request(req); + + vbr->sg_table.nents = virtblk_map_data(hctx, req, vbr); + if (unlikely(vbr->sg_table.nents < 0)) { + virtblk_cleanup_cmd(req); + return BLK_STS_RESOURCE; + } + + return BLK_STS_OK; +} + static blk_status_t virtio_queue_rq(struct blk_mq_hw_ctx *hctx, const struct blk_mq_queue_data *bd) { @@ -311,26 +332,17 @@ static blk_status_t virtio_queue_rq(struct blk_mq_hw_ctx *hctx, struct request *req = bd->rq; struct virtblk_req *vbr = blk_mq_rq_to_pdu(req); unsigned long flags; - int num; int qid = hctx->queue_num; bool notify = false; blk_status_t status; int err; - status = virtblk_setup_cmd(vblk->vdev, req, vbr); + status = virtblk_prep_rq(hctx, vblk, req, vbr); if (unlikely(status)) return status; - blk_mq_start_request(req); - - num = virtblk_map_data(hctx, req, vbr); - if (unlikely(num < 0)) { - virtblk_cleanup_cmd(req); - return BLK_STS_RESOURCE; - } - spin_lock_irqsave(&vblk->vqs[qid].lock, flags); - err = virtblk_add_req(vblk->vqs[qid].vq, vbr, vbr->sg_table.sgl, num); + err = virtblk_add_req(vblk->vqs[qid].vq, vbr); if (err) { virtqueue_kick(vblk->vqs[qid].vq); /* Don't stop the queue if -ENOMEM: we may have failed to @@ -360,6 +372,75 @@ static blk_status_t virtio_queue_rq(struct blk_mq_hw_ctx *hctx, return BLK_STS_OK; } +static bool virtblk_prep_rq_batch(struct request *req) +{ + struct virtio_blk *vblk = req->mq_hctx->queue->queuedata; + struct virtblk_req *vbr = blk_mq_rq_to_pdu(req); + + req->mq_hctx->tags->rqs[req->tag] = req; + + return virtblk_prep_rq(req->mq_hctx, vblk, req, vbr) == BLK_STS_OK; +} + +static bool virtblk_add_req_batch(struct virtio_blk_vq *vq, + struct request **rqlist, + struct request **requeue_list) +{ + unsigned long flags; + int err; + bool kick; + + spin_lock_irqsave(&vq->lock, flags); + + while (!rq_list_empty(*rqlist)) { + struct request *req = rq_list_pop(rqlist); + struct virtblk_req *vbr = blk_mq_rq_to_pdu(req); + + err = virtblk_add_req(vq->vq, vbr); + if (err) { + virtblk_unmap_data(req, vbr); + virtblk_cleanup_cmd(req); + rq_list_add(requeue_list, req); + } + } + + kick = virtqueue_kick_prepare(vq->vq); + spin_unlock_irqrestore(&vq->lock, flags); + + return kick; +} + +static void virtio_queue_rqs(struct request **rqlist) +{ + struct request *req, *next, *prev = NULL; + struct request *requeue_list = NULL; + + rq_list_for_each_safe(rqlist, req, next) { + struct virtio_blk_vq *vq = req->mq_hctx->driver_data; + bool kick; + + if (!virtblk_prep_rq_batch(req)) { + rq_list_move(rqlist, &requeue_list, req, prev); + req = prev; + if (!req) + continue; + } + + if (!next || req->mq_hctx != next->mq_hctx) { + req->rq_next = NULL; + kick = virtblk_add_req_batch(vq, rqlist, &requeue_list); + if (kick) + virtqueue_notify(vq->vq); + + *rqlist = next; + prev = NULL; + } else + prev = req; + } + + *rqlist = requeue_list; +} + /* return id (s/n) string for *disk to *id_str */ static int virtblk_get_id(struct gendisk *disk, char *id_str) @@ -794,6 +875,7 @@ static int virtblk_init_hctx(struct blk_mq_hw_ctx *hctx, void *data, static const struct blk_mq_ops virtio_mq_ops = { .queue_rq = virtio_queue_rq, + .queue_rqs = virtio_queue_rqs, .commit_rqs = virtio_commit_rqs, .init_hctx = virtblk_init_hctx, .complete = virtblk_request_done, |