qemu-kvm/SOURCES/kvm-vdpa-Make-SVQ-vring-unmapping-return-void.patch

From 8e36feb4d3480b7c09d9dcbde18c9db1e8063f18 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Eugenio=20P=C3=A9rez?= <eperezma@redhat.com>
Date: Tue, 23 Aug 2022 20:20:06 +0200
Subject: [PATCH 08/23] vdpa: Make SVQ vring unmapping return void
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RH-Author: Eugenio Pérez <eperezma@redhat.com>
RH-MergeRequest: 116: vdpa: Restore device state on destination
RH-Bugzilla: 2114060
RH-Acked-by: Cindy Lu <lulu@redhat.com>
RH-Acked-by: Miroslav Rezanina <mrezanin@redhat.com>
RH-Commit: [7/21] 3366340dc7ae65f83894f5d0da0d1e0f64713751 (eperezmartin/qemu-kvm)
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=2114060
Upstream status: git@github.com:jasowang/qemu.git net-next

Nothing actually reads the return value, but an error in cleaning some
entries could cause device stop to abort, making a restart impossible.
Better ignore explicitely the return value.

Reported-by: Lei Yang <leiyang@redhat.com>
Fixes: 34e3c94eda ("vdpa: Add custom IOTLB translations to SVQ")
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
(cherry picked from commit bb5cf89ef2338ab6be946ede6821c3f61347eb1b)
---
 hw/virtio/vhost-vdpa.c | 32 ++++++++++----------------------
 1 file changed, 10 insertions(+), 22 deletions(-)

diff --git a/hw/virtio/vhost-vdpa.c b/hw/virtio/vhost-vdpa.c
index e5c264fb29..8eddf39f2a 100644
--- a/hw/virtio/vhost-vdpa.c
+++ b/hw/virtio/vhost-vdpa.c
@@ -882,7 +882,7 @@ static int vhost_vdpa_svq_set_fds(struct vhost_dev *dev,
 /**
  * Unmap a SVQ area in the device
  */
-static bool vhost_vdpa_svq_unmap_ring(struct vhost_vdpa *v,
+static void vhost_vdpa_svq_unmap_ring(struct vhost_vdpa *v,
                                       const DMAMap *needle)
 {
     const DMAMap *result = vhost_iova_tree_find_iova(v->iova_tree, needle);
@@ -891,38 +891,33 @@ static bool vhost_vdpa_svq_unmap_ring(struct vhost_vdpa *v,
 
     if (unlikely(!result)) {
         error_report("Unable to find SVQ address to unmap");
-        return false;
+        return;
     }
 
     size = ROUND_UP(result->size, qemu_real_host_page_size);
     r = vhost_vdpa_dma_unmap(v, result->iova, size);
     if (unlikely(r < 0)) {
         error_report("Unable to unmap SVQ vring: %s (%d)", g_strerror(-r), -r);
-        return false;
+        return;
     }
 
     vhost_iova_tree_remove(v->iova_tree, *result);
-    return r == 0;
 }
 
-static bool vhost_vdpa_svq_unmap_rings(struct vhost_dev *dev,
+static void vhost_vdpa_svq_unmap_rings(struct vhost_dev *dev,
                                        const VhostShadowVirtqueue *svq)
 {
     DMAMap needle = {};
     struct vhost_vdpa *v = dev->opaque;
     struct vhost_vring_addr svq_addr;
-    bool ok;
 
     vhost_svq_get_vring_addr(svq, &svq_addr);
 
     needle.translated_addr = svq_addr.desc_user_addr;
-    ok = vhost_vdpa_svq_unmap_ring(v, &needle);
-    if (unlikely(!ok)) {
-        return false;
-    }
+    vhost_vdpa_svq_unmap_ring(v, &needle);
 
     needle.translated_addr = svq_addr.used_user_addr;
-    return vhost_vdpa_svq_unmap_ring(v, &needle);
+    vhost_vdpa_svq_unmap_ring(v, &needle);
 }
 
 /**
@@ -1093,26 +1088,22 @@ err:
     return false;
 }
 
-static bool vhost_vdpa_svqs_stop(struct vhost_dev *dev)
+static void vhost_vdpa_svqs_stop(struct vhost_dev *dev)
 {
     struct vhost_vdpa *v = dev->opaque;
 
     if (!v->shadow_vqs) {
-        return true;
+        return;
     }
 
     for (unsigned i = 0; i < v->shadow_vqs->len; ++i) {
         VhostShadowVirtqueue *svq = g_ptr_array_index(v->shadow_vqs, i);
-        bool ok = vhost_vdpa_svq_unmap_rings(dev, svq);
-        if (unlikely(!ok)) {
-            return false;
-        }
+        vhost_vdpa_svq_unmap_rings(dev, svq);
     }
 
     if (v->migration_blocker) {
         migrate_del_blocker(v->migration_blocker);
     }
-    return true;
 }
 
 static int vhost_vdpa_dev_start(struct vhost_dev *dev, bool started)
@@ -1129,10 +1120,7 @@ static int vhost_vdpa_dev_start(struct vhost_dev *dev, bool started)
         }
         vhost_vdpa_set_vring_ready(dev);
     } else {
-        ok = vhost_vdpa_svqs_stop(dev);
-        if (unlikely(!ok)) {
-            return -1;
-        }
+        vhost_vdpa_svqs_stop(dev);
         vhost_vdpa_host_notifiers_uninit(dev, dev->nvqs);
     }
 
-- 
2.31.1