qemu-kvm/kvm-vdpa-request-iova_range-only-once.patch

From 760169d538a4e6ba61006f6796cd55af967a7f1e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Eugenio=20P=C3=A9rez?= <eperezma@redhat.com>
Date: Thu, 15 Dec 2022 12:31:38 +0100
Subject: [PATCH 06/14] vdpa: request iova_range only once
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

RH-Author: Eugenio Pérez <eperezma@redhat.com>
RH-MergeRequest: 136: vDPA ASID support in Qemu
RH-Bugzilla: 2104412
RH-Acked-by: Laurent Vivier <lvivier@redhat.com>
RH-Acked-by: Cindy Lu <lulu@redhat.com>
RH-Acked-by: Miroslav Rezanina <mrezanin@redhat.com>
RH-Commit: [6/13] 2a8ae2f46ae88f01c5535038f38cb7895098b610 (eperezmartin/qemu-kvm)

Currently iova range is requested once per queue pair in the case of
net. Reduce the number of ioctls asking it once at initialization and
reusing that value for each vhost_vdpa.

Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Message-Id: <20221215113144.322011-7-eperezma@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasonwang@redhat.com>
(cherry picked from commit a585fad26b2e6ccca156d9e65158ad1c5efd268d)
---
 hw/virtio/vhost-vdpa.c | 15 ---------------
 net/vhost-vdpa.c       | 27 ++++++++++++++-------------
 2 files changed, 14 insertions(+), 28 deletions(-)

diff --git a/hw/virtio/vhost-vdpa.c b/hw/virtio/vhost-vdpa.c
index e65603022f..9e7cbf1776 100644
--- a/hw/virtio/vhost-vdpa.c
+++ b/hw/virtio/vhost-vdpa.c
@@ -365,19 +365,6 @@ static int vhost_vdpa_add_status(struct vhost_dev *dev, uint8_t status)
     return 0;
 }
 
-static void vhost_vdpa_get_iova_range(struct vhost_vdpa *v)
-{
-    int ret = vhost_vdpa_call(v->dev, VHOST_VDPA_GET_IOVA_RANGE,
-                              &v->iova_range);
-    if (ret != 0) {
-        v->iova_range.first = 0;
-        v->iova_range.last = UINT64_MAX;
-    }
-
-    trace_vhost_vdpa_get_iova_range(v->dev, v->iova_range.first,
-                                    v->iova_range.last);
-}
-
 /*
  * The use of this function is for requests that only need to be
  * applied once. Typically such request occurs at the beginning
@@ -465,8 +452,6 @@ static int vhost_vdpa_init(struct vhost_dev *dev, void *opaque, Error **errp)
         goto err;
     }
 
-    vhost_vdpa_get_iova_range(v);
-
     if (!vhost_vdpa_first_dev(dev)) {
         return 0;
     }
diff --git a/net/vhost-vdpa.c b/net/vhost-vdpa.c
index 16a5ebe2dd..8d3ed095d0 100644
--- a/net/vhost-vdpa.c
+++ b/net/vhost-vdpa.c
@@ -549,14 +549,15 @@ static const VhostShadowVirtqueueOps vhost_vdpa_net_svq_ops = {
 };
 
 static NetClientState *net_vhost_vdpa_init(NetClientState *peer,
-                                           const char *device,
-                                           const char *name,
-                                           int vdpa_device_fd,
-                                           int queue_pair_index,
-                                           int nvqs,
-                                           bool is_datapath,
-                                           bool svq,
-                                           VhostIOVATree *iova_tree)
+                                       const char *device,
+                                       const char *name,
+                                       int vdpa_device_fd,
+                                       int queue_pair_index,
+                                       int nvqs,
+                                       bool is_datapath,
+                                       bool svq,
+                                       struct vhost_vdpa_iova_range iova_range,
+                                       VhostIOVATree *iova_tree)
 {
     NetClientState *nc = NULL;
     VhostVDPAState *s;
@@ -575,6 +576,7 @@ static NetClientState *net_vhost_vdpa_init(NetClientState *peer,
     s->vhost_vdpa.device_fd = vdpa_device_fd;
     s->vhost_vdpa.index = queue_pair_index;
     s->vhost_vdpa.shadow_vqs_enabled = svq;
+    s->vhost_vdpa.iova_range = iova_range;
     s->vhost_vdpa.iova_tree = iova_tree;
     if (!is_datapath) {
         s->cvq_cmd_out_buffer = qemu_memalign(qemu_real_host_page_size(),
@@ -654,6 +656,7 @@ int net_init_vhost_vdpa(const Netdev *netdev, const char *name,
     int vdpa_device_fd;
     g_autofree NetClientState **ncs = NULL;
     g_autoptr(VhostIOVATree) iova_tree = NULL;
+    struct vhost_vdpa_iova_range iova_range;
     NetClientState *nc;
     int queue_pairs, r, i = 0, has_cvq = 0;
 
@@ -697,14 +700,12 @@ int net_init_vhost_vdpa(const Netdev *netdev, const char *name,
         return queue_pairs;
     }
 
+    vhost_vdpa_get_iova_range(vdpa_device_fd, &iova_range);
     if (opts->x_svq) {
-        struct vhost_vdpa_iova_range iova_range;
-
         if (!vhost_vdpa_net_valid_svq_features(features, errp)) {
             goto err_svq;
         }
 
-        vhost_vdpa_get_iova_range(vdpa_device_fd, &iova_range);
         iova_tree = vhost_iova_tree_new(iova_range.first, iova_range.last);
     }
 
@@ -713,7 +714,7 @@ int net_init_vhost_vdpa(const Netdev *netdev, const char *name,
     for (i = 0; i < queue_pairs; i++) {
         ncs[i] = net_vhost_vdpa_init(peer, TYPE_VHOST_VDPA, name,
                                      vdpa_device_fd, i, 2, true, opts->x_svq,
-                                     iova_tree);
+                                     iova_range, iova_tree);
         if (!ncs[i])
             goto err;
     }
@@ -721,7 +722,7 @@ int net_init_vhost_vdpa(const Netdev *netdev, const char *name,
     if (has_cvq) {
         nc = net_vhost_vdpa_init(peer, TYPE_VHOST_VDPA, name,
                                  vdpa_device_fd, i, 1, false,
-                                 opts->x_svq, iova_tree);
+                                 opts->x_svq, iova_range, iova_tree);
         if (!nc)
             goto err;
     }
-- 
2.31.1