Re: [PATCH V5 5/5] scsi: virtio_scsi: unify scsi_host_template

2018-03-14 Thread Christoph Hellwig
Looks good,

Reviewed-by: Christoph Hellwig 


[PATCH V5 5/5] scsi: virtio_scsi: unify scsi_host_template

2018-03-13 Thread Ming Lei
Now we switch to use_blk_mq always, and both single queue and multi
queue cases can be handled in one .queuecommand callback, not necessary
to use two scsi_host_template.

Suggested-by: Christoph Hellwig ,
Cc: Omar Sandoval ,
Cc: "Martin K. Petersen" ,
Cc: James Bottomley ,
Cc: Christoph Hellwig ,
Cc: Paolo Bonzini 
Cc: Mike Snitzer 
Cc: Laurence Oberman 
Cc: Hannes Reinecke 
Signed-off-by: Ming Lei 
---
 drivers/scsi/virtio_scsi.c | 74 ++
 1 file changed, 15 insertions(+), 59 deletions(-)

diff --git a/drivers/scsi/virtio_scsi.c b/drivers/scsi/virtio_scsi.c
index 54e3a0f6844c..45d04631888a 100644
--- 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) + sizeo