scsi: virtio_scsi: unify scsi_host_template

Now that virtio_scsi uses blk-mq exclusively, we can remove the
scsi_host_template and associated plumbing for the legacy I/O path.

[mkp: commit desc]

Cc: Omar Sandoval <osandov@fb.com>,
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>,
Cc: James Bottomley <james.bottomley@hansenpartnership.com>,
Cc: Christoph Hellwig <hch@lst.de>,
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Mike Snitzer <snitzer@redhat.com>
Cc: Laurence Oberman <loberman@redhat.com>
Cc: Hannes Reinecke <hare@suse.de>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Suggested-by: Christoph Hellwig <hch@lst.de>,
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/scsi/virtio_scsi.c b/drivers/scsi/virtio_scsi.c
index 54e3a0f6844c4c81692fe9aaa568efe1f2215866..45d04631888a4f67d0884971226074c6628a063d 100644 (file)
--- a/drivers/scsi/virtio_scsi.c
+++ b/drivers/scsi/virtio_scsi.c
@@ -522,11 +522,20 @@ static void virtio_scsi_init_hdr_pi(struct virtio_device *vdev,
 }
 #endif
 
-static int virtscsi_queuecommand(struct virtio_scsi *vscsi,
-                                struct virtio_scsi_vq *req_vq,
+static struct virtio_scsi_vq *virtscsi_pick_vq_mq(struct virtio_scsi *vscsi,
+                                                 struct scsi_cmnd *sc)
+{
+       u32 tag = blk_mq_unique_tag(sc->request);
+       u16 hwq = blk_mq_unique_tag_to_hwq(tag);
+
+       return &vscsi->req_vqs[hwq];
+}
+
+static int virtscsi_queuecommand(struct Scsi_Host *shost,
                                 struct scsi_cmnd *sc)
 {
-       struct Scsi_Host *shost = virtio_scsi_host(vscsi->vdev);
+       struct virtio_scsi *vscsi = shost_priv(shost);
+       struct virtio_scsi_vq *req_vq = virtscsi_pick_vq_mq(vscsi, sc);
        struct virtio_scsi_cmd *cmd = scsi_cmd_priv(sc);
        unsigned long flags;
        int req_size;
@@ -569,32 +578,6 @@ static int virtscsi_queuecommand(struct virtio_scsi *vscsi,
        return 0;
 }
 
-static int virtscsi_queuecommand_single(struct Scsi_Host *sh,
-                                       struct scsi_cmnd *sc)
-{
-       struct virtio_scsi *vscsi = shost_priv(sh);
-
-       return virtscsi_queuecommand(vscsi, &vscsi->req_vqs[0], sc);
-}
-
-static struct virtio_scsi_vq *virtscsi_pick_vq_mq(struct virtio_scsi *vscsi,
-                                                 struct scsi_cmnd *sc)
-{
-       u32 tag = blk_mq_unique_tag(sc->request);
-       u16 hwq = blk_mq_unique_tag_to_hwq(tag);
-
-       return &vscsi->req_vqs[hwq];
-}
-
-static int virtscsi_queuecommand_multi(struct Scsi_Host *sh,
-                                      struct scsi_cmnd *sc)
-{
-       struct virtio_scsi *vscsi = shost_priv(sh);
-       struct virtio_scsi_vq *req_vq = virtscsi_pick_vq_mq(vscsi, sc);
-
-       return virtscsi_queuecommand(vscsi, req_vq, sc);
-}
-
 static int virtscsi_tmf(struct virtio_scsi *vscsi, struct virtio_scsi_cmd *cmd)
 {
        DECLARE_COMPLETION_ONSTACK(comp);
@@ -750,34 +733,13 @@ static enum blk_eh_timer_return virtscsi_eh_timed_out(struct scsi_cmnd *scmnd)
        return BLK_EH_RESET_TIMER;
 }
 
-static struct scsi_host_template virtscsi_host_template_single = {
-       .module = THIS_MODULE,
-       .name = "Virtio SCSI HBA",
-       .proc_name = "virtio_scsi",
-       .this_id = -1,
-       .cmd_size = sizeof(struct virtio_scsi_cmd),
-       .queuecommand = virtscsi_queuecommand_single,
-       .change_queue_depth = virtscsi_change_queue_depth,
-       .eh_abort_handler = virtscsi_abort,
-       .eh_device_reset_handler = virtscsi_device_reset,
-       .eh_timed_out = virtscsi_eh_timed_out,
-       .slave_alloc = virtscsi_device_alloc,
-
-       .dma_boundary = UINT_MAX,
-       .use_clustering = ENABLE_CLUSTERING,
-       .target_alloc = virtscsi_target_alloc,
-       .target_destroy = virtscsi_target_destroy,
-       .track_queue_depth = 1,
-       .force_blk_mq = 1,
-};
-
-static struct scsi_host_template virtscsi_host_template_multi = {
+static struct scsi_host_template virtscsi_host_template = {
        .module = THIS_MODULE,
        .name = "Virtio SCSI HBA",
        .proc_name = "virtio_scsi",
        .this_id = -1,
        .cmd_size = sizeof(struct virtio_scsi_cmd),
-       .queuecommand = virtscsi_queuecommand_multi,
+       .queuecommand = virtscsi_queuecommand,
        .change_queue_depth = virtscsi_change_queue_depth,
        .eh_abort_handler = virtscsi_abort,
        .eh_device_reset_handler = virtscsi_device_reset,
@@ -883,7 +845,6 @@ static int virtscsi_probe(struct virtio_device *vdev)
        u32 sg_elems, num_targets;
        u32 cmd_per_lun;
        u32 num_queues;
-       struct scsi_host_template *hostt;
 
        if (!vdev->config->get) {
                dev_err(&vdev->dev, "%s failure: config access disabled\n",
@@ -896,12 +857,7 @@ static int virtscsi_probe(struct virtio_device *vdev)
 
        num_targets = virtscsi_config_get(vdev, max_target) + 1;
 
-       if (num_queues == 1)
-               hostt = &virtscsi_host_template_single;
-       else
-               hostt = &virtscsi_host_template_multi;
-
-       shost = scsi_host_alloc(hostt,
+       shost = scsi_host_alloc(&virtscsi_host_template,
                sizeof(*vscsi) + sizeof(vscsi->req_vqs[0]) * num_queues);
        if (!shost)
                return -ENOMEM;