[Qemu-devel] [PATCH 2/3] virtio-scsi: Deduplicate cmd queue handling code of dataplane

[Fam Zheng <famz@redhat.com>]

The common logic of cmd handling will grow, now there is repeat,
converge them to one place.

Signed-off-by: Fam Zheng <famz@redhat.com>
---
 hw/scsi/virtio-scsi-dataplane.c | 15 +++------------
 hw/scsi/virtio-scsi.c           | 27 ++++++++++++++++++---------
 include/hw/virtio/virtio-scsi.h |  8 ++++++--
 3 files changed, 27 insertions(+), 23 deletions(-)

diff --git a/hw/scsi/virtio-scsi-dataplane.c b/hw/scsi/virtio-scsi-dataplane.c
index 03a1e8c..4a9b9bd 100644
--- a/hw/scsi/virtio-scsi-dataplane.c
+++ b/hw/scsi/virtio-scsi-dataplane.c
@@ -137,20 +137,11 @@ static void virtio_scsi_iothread_handle_cmd(EventNotifier *notifier)
 {
     VirtIOSCSIVring *vring = container_of(notifier,
                                           VirtIOSCSIVring, host_notifier);
-    VirtIOSCSI *s = (VirtIOSCSI *)vring->parent;
-    VirtIOSCSIReq *req, *next;
-    QTAILQ_HEAD(, VirtIOSCSIReq) reqs = QTAILQ_HEAD_INITIALIZER(reqs);
 
     event_notifier_test_and_clear(notifier);
-    while ((req = virtio_scsi_pop_req_vring(s, vring))) {
-        if (virtio_scsi_handle_cmd_req_prepare(s, req)) {
-            QTAILQ_INSERT_TAIL(&reqs, req, next);
-        }
-    }
-
-    QTAILQ_FOREACH_SAFE(req, &reqs, next, next) {
-        virtio_scsi_handle_cmd_req_submit(s, req);
-    }
+    virtio_scsi_handle_cmd_do(vring->parent,
+                              (VirtIOSCSIPopFunc)virtio_scsi_pop_req_vring,
+                              vring);
 }
 
 /* assumes s->ctx held */
diff --git a/hw/scsi/virtio-scsi.c b/hw/scsi/virtio-scsi.c
index 9e2c718..ae8b79a 100644
--- a/hw/scsi/virtio-scsi.c
+++ b/hw/scsi/virtio-scsi.c
@@ -517,7 +517,8 @@ static void virtio_scsi_fail_cmd_req(VirtIOSCSIReq *req)
     virtio_scsi_complete_cmd_req(req);
 }
 
-bool virtio_scsi_handle_cmd_req_prepare(VirtIOSCSI *s, VirtIOSCSIReq *req)
+static bool virtio_scsi_handle_cmd_req_prepare(VirtIOSCSI *s,
+                                               VirtIOSCSIReq *req)
 {
     VirtIOSCSICommon *vs = &s->parent_obj;
     SCSIDevice *d;
@@ -561,7 +562,7 @@ bool virtio_scsi_handle_cmd_req_prepare(VirtIOSCSI *s, VirtIOSCSIReq *req)
     return true;
 }
 
-void virtio_scsi_handle_cmd_req_submit(VirtIOSCSI *s, VirtIOSCSIReq *req)
+static void virtio_scsi_handle_cmd_req_submit(VirtIOSCSI *s, VirtIOSCSIReq *req)
 {
     SCSIRequest *sreq = req->sreq;
     if (scsi_req_enqueue(sreq)) {
@@ -571,18 +572,15 @@ void virtio_scsi_handle_cmd_req_submit(VirtIOSCSI *s, VirtIOSCSIReq *req)
     scsi_req_unref(sreq);
 }
 
-static void virtio_scsi_handle_cmd(VirtIODevice *vdev, VirtQueue *vq)
+void virtio_scsi_handle_cmd_do(VirtIOSCSI *s,
+                               VirtIOSCSIPopFunc pop_req,
+                               void *opaque)
 {
     /* use non-QOM casts in the data path */
-    VirtIOSCSI *s = (VirtIOSCSI *)vdev;
     VirtIOSCSIReq *req, *next;
     QTAILQ_HEAD(, VirtIOSCSIReq) reqs = QTAILQ_HEAD_INITIALIZER(reqs);
 
-    if (s->ctx && !s->dataplane_disabled) {
-        virtio_scsi_dataplane_start(s);
-        return;
-    }
-    while ((req = virtio_scsi_pop_req(s, vq))) {
+    while ((req = pop_req(s, opaque))) {
         if (virtio_scsi_handle_cmd_req_prepare(s, req)) {
             QTAILQ_INSERT_TAIL(&reqs, req, next);
         }
@@ -593,6 +591,17 @@ static void virtio_scsi_handle_cmd(VirtIODevice *vdev, VirtQueue *vq)
     }
 }
 
+static void virtio_scsi_handle_cmd(VirtIODevice *vdev, VirtQueue *vq)
+{
+    VirtIOSCSI *s = (VirtIOSCSI *)vdev;
+
+    if (s->ctx && !s->dataplane_disabled) {
+        virtio_scsi_dataplane_start(s);
+        return;
+    }
+    virtio_scsi_handle_cmd_do(s, (VirtIOSCSIPopFunc)virtio_scsi_pop_req, vq);
+}
+
 static void virtio_scsi_get_config(VirtIODevice *vdev,
                                    uint8_t *config)
 {
diff --git a/include/hw/virtio/virtio-scsi.h b/include/hw/virtio/virtio-scsi.h
index bf17cc9..cba82ea 100644
--- a/include/hw/virtio/virtio-scsi.h
+++ b/include/hw/virtio/virtio-scsi.h
@@ -268,8 +268,12 @@ void virtio_scsi_common_realize(DeviceState *dev, Error **errp,
 
 void virtio_scsi_common_unrealize(DeviceState *dev, Error **errp);
 void virtio_scsi_handle_ctrl_req(VirtIOSCSI *s, VirtIOSCSIReq *req);
-bool virtio_scsi_handle_cmd_req_prepare(VirtIOSCSI *s, VirtIOSCSIReq *req);
-void virtio_scsi_handle_cmd_req_submit(VirtIOSCSI *s, VirtIOSCSIReq *req);
+
+typedef VirtIOSCSIReq *(*VirtIOSCSIPopFunc)(VirtIOSCSI *, void *);
+void virtio_scsi_handle_cmd_do(VirtIOSCSI *s,
+                               VirtIOSCSIPopFunc pop_req,
+                               void *opaque);
+
 VirtIOSCSIReq *virtio_scsi_init_req(VirtIOSCSI *s, VirtQueue *vq);
 void virtio_scsi_free_req(VirtIOSCSIReq *req);
 void virtio_scsi_push_event(VirtIOSCSI *s, SCSIDevice *dev,
-- 
1.9.3