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-rw-r--r--hw/net/vhost_net.c52
-rw-r--r--hw/net/virtio-net.c68
-rw-r--r--hw/pci-bridge/dec.c6
-rw-r--r--hw/pci-bridge/i82801b11.c5
-rw-r--r--hw/pci-bridge/ioh3420.c6
-rw-r--r--hw/pci-bridge/pci_bridge_dev.c8
-rw-r--r--hw/pci-bridge/xio3130_downstream.c6
-rw-r--r--hw/pci-bridge/xio3130_upstream.c6
-rw-r--r--hw/pci-host/apb.c7
-rw-r--r--hw/pci/msix.c4
-rw-r--r--hw/pci/pci_bridge.c3
-rw-r--r--hw/virtio/vhost.c36
-rw-r--r--hw/virtio/virtio-pci.c14
-rw-r--r--hw/virtio/virtio.c1
14 files changed, 137 insertions, 85 deletions
diff --git a/hw/net/vhost_net.c b/hw/net/vhost_net.c
index 3940a04b65..6e1032fc18 100644
--- a/hw/net/vhost_net.c
+++ b/hw/net/vhost_net.c
@@ -36,7 +36,6 @@
 #include "standard-headers/linux/virtio_ring.h"
 #include "hw/virtio/vhost.h"
 #include "hw/virtio/virtio-bus.h"
-#include "hw/virtio/virtio-access.h"
 
 struct vhost_net {
     struct vhost_dev dev;
@@ -197,27 +196,6 @@ static void vhost_net_set_vq_index(struct vhost_net *net, int vq_index)
     net->dev.vq_index = vq_index;
 }
 
-static int vhost_net_set_vnet_endian(VirtIODevice *dev, NetClientState *peer,
-                                     bool set)
-{
-    int r = 0;
-
-    if (virtio_vdev_has_feature(dev, VIRTIO_F_VERSION_1) ||
-        (virtio_legacy_is_cross_endian(dev) && !virtio_is_big_endian(dev))) {
-        r = qemu_set_vnet_le(peer, set);
-        if (r) {
-            error_report("backend does not support LE vnet headers");
-        }
-    } else if (virtio_legacy_is_cross_endian(dev)) {
-        r = qemu_set_vnet_be(peer, set);
-        if (r) {
-            error_report("backend does not support BE vnet headers");
-        }
-    }
-
-    return r;
-}
-
 static int vhost_net_start_one(struct vhost_net *net,
                                VirtIODevice *dev)
 {
@@ -298,25 +276,32 @@ int vhost_net_start(VirtIODevice *dev, NetClientState *ncs,
     BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(dev)));
     VirtioBusState *vbus = VIRTIO_BUS(qbus);
     VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(vbus);
-    int r, e, i, j;
+    int r, e, i;
 
     if (!k->set_guest_notifiers) {
         error_report("binding does not support guest notifiers");
         return -ENOSYS;
     }
 
-    for (j = 0; j < total_queues; j++) {
-        r = vhost_net_set_vnet_endian(dev, ncs[j].peer, true);
-        if (r < 0) {
-            goto err_endian;
+    for (i = 0; i < total_queues; i++) {
+        struct vhost_net *net;
+
+        net = get_vhost_net(ncs[i].peer);
+        vhost_net_set_vq_index(net, i * 2);
+
+        /* Suppress the masking guest notifiers on vhost user
+         * because vhost user doesn't interrupt masking/unmasking
+         * properly.
+         */
+        if (net->nc->info->type == NET_CLIENT_OPTIONS_KIND_VHOST_USER) {
+                dev->use_guest_notifier_mask = false;
         }
-        vhost_net_set_vq_index(get_vhost_net(ncs[j].peer), j * 2);
-    }
+     }
 
     r = k->set_guest_notifiers(qbus->parent, total_queues * 2, true);
     if (r < 0) {
         error_report("Error binding guest notifier: %d", -r);
-        goto err_endian;
+        goto err;
     }
 
     for (i = 0; i < total_queues; i++) {
@@ -338,10 +323,7 @@ err_start:
         fprintf(stderr, "vhost guest notifier cleanup failed: %d\n", e);
         fflush(stderr);
     }
-err_endian:
-    while (--j >= 0) {
-        vhost_net_set_vnet_endian(dev, ncs[j].peer, false);
-    }
+err:
     return r;
 }
 
@@ -363,8 +345,6 @@ void vhost_net_stop(VirtIODevice *dev, NetClientState *ncs,
         fflush(stderr);
     }
     assert(r >= 0);
-
-    assert(vhost_net_set_vnet_endian(dev, ncs[0].peer, false) >= 0);
 }
 
 void vhost_net_cleanup(struct vhost_net *net)
diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c
index de696e8dd0..5798f87d8e 100644
--- a/hw/net/virtio-net.c
+++ b/hw/net/virtio-net.c
@@ -129,6 +129,13 @@ static void virtio_net_vhost_status(VirtIONet *n, uint8_t status)
     if (!n->vhost_started) {
         int r, i;
 
+        if (n->needs_vnet_hdr_swap) {
+            error_report("backend does not support %s vnet headers; "
+                         "falling back on userspace virtio",
+                         virtio_is_big_endian(vdev) ? "BE" : "LE");
+            return;
+        }
+
         /* Any packets outstanding? Purge them to avoid touching rings
          * when vhost is running.
          */
@@ -153,6 +160,59 @@ static void virtio_net_vhost_status(VirtIONet *n, uint8_t status)
     }
 }
 
+static int virtio_net_set_vnet_endian_one(VirtIODevice *vdev,
+                                          NetClientState *peer,
+                                          bool enable)
+{
+    if (virtio_is_big_endian(vdev)) {
+        return qemu_set_vnet_be(peer, enable);
+    } else {
+        return qemu_set_vnet_le(peer, enable);
+    }
+}
+
+static bool virtio_net_set_vnet_endian(VirtIODevice *vdev, NetClientState *ncs,
+                                       int queues, bool enable)
+{
+    int i;
+
+    for (i = 0; i < queues; i++) {
+        if (virtio_net_set_vnet_endian_one(vdev, ncs[i].peer, enable) < 0 &&
+            enable) {
+            while (--i >= 0) {
+                virtio_net_set_vnet_endian_one(vdev, ncs[i].peer, false);
+            }
+
+            return true;
+        }
+    }
+
+    return false;
+}
+
+static void virtio_net_vnet_endian_status(VirtIONet *n, uint8_t status)
+{
+    VirtIODevice *vdev = VIRTIO_DEVICE(n);
+    int queues = n->multiqueue ? n->max_queues : 1;
+
+    if (virtio_net_started(n, status)) {
+        /* Before using the device, we tell the network backend about the
+         * endianness to use when parsing vnet headers. If the backend
+         * can't do it, we fallback onto fixing the headers in the core
+         * virtio-net code.
+         */
+        n->needs_vnet_hdr_swap = virtio_net_set_vnet_endian(vdev, n->nic->ncs,
+                                                            queues, true);
+    } else if (virtio_net_started(n, vdev->status)) {
+        /* After using the device, we need to reset the network backend to
+         * the default (guest native endianness), otherwise the guest may
+         * lose network connectivity if it is rebooted into a different
+         * endianness.
+         */
+        virtio_net_set_vnet_endian(vdev, n->nic->ncs, queues, false);
+    }
+}
+
 static void virtio_net_set_status(struct VirtIODevice *vdev, uint8_t status)
 {
     VirtIONet *n = VIRTIO_NET(vdev);
@@ -160,6 +220,7 @@ static void virtio_net_set_status(struct VirtIODevice *vdev, uint8_t status)
     int i;
     uint8_t queue_status;
 
+    virtio_net_vnet_endian_status(n, status);
     virtio_net_vhost_status(n, status);
 
     for (i = 0; i < n->max_queues; i++) {
@@ -963,7 +1024,10 @@ static void receive_header(VirtIONet *n, const struct iovec *iov, int iov_cnt,
         void *wbuf = (void *)buf;
         work_around_broken_dhclient(wbuf, wbuf + n->host_hdr_len,
                                     size - n->host_hdr_len);
-        virtio_net_hdr_swap(VIRTIO_DEVICE(n), wbuf);
+
+        if (n->needs_vnet_hdr_swap) {
+            virtio_net_hdr_swap(VIRTIO_DEVICE(n), wbuf);
+        }
         iov_from_buf(iov, iov_cnt, 0, buf, sizeof(struct virtio_net_hdr));
     } else {
         struct virtio_net_hdr hdr = {
@@ -1184,7 +1248,7 @@ static int32_t virtio_net_flush_tx(VirtIONetQueue *q)
                 error_report("virtio-net header incorrect");
                 exit(1);
             }
-            if (virtio_needs_swap(vdev)) {
+            if (n->needs_vnet_hdr_swap) {
                 virtio_net_hdr_swap(vdev, (void *) &mhdr);
                 sg2[0].iov_base = &mhdr;
                 sg2[0].iov_len = n->guest_hdr_len;
diff --git a/hw/pci-bridge/dec.c b/hw/pci-bridge/dec.c
index 40ff0d0632..840c96198a 100644
--- a/hw/pci-bridge/dec.c
+++ b/hw/pci-bridge/dec.c
@@ -52,9 +52,9 @@ static int dec_map_irq(PCIDevice *pci_dev, int irq_num)
     return irq_num;
 }
 
-static int dec_pci_bridge_initfn(PCIDevice *pci_dev)
+static void dec_pci_bridge_realize(PCIDevice *pci_dev, Error **errp)
 {
-    return pci_bridge_initfn(pci_dev, TYPE_PCI_BUS);
+    pci_bridge_initfn(pci_dev, TYPE_PCI_BUS);
 }
 
 static void dec_21154_pci_bridge_class_init(ObjectClass *klass, void *data)
@@ -62,7 +62,7 @@ static void dec_21154_pci_bridge_class_init(ObjectClass *klass, void *data)
     DeviceClass *dc = DEVICE_CLASS(klass);
     PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);
 
-    k->init = dec_pci_bridge_initfn;
+    k->realize = dec_pci_bridge_realize;
     k->exit = pci_bridge_exitfn;
     k->vendor_id = PCI_VENDOR_ID_DEC;
     k->device_id = PCI_DEVICE_ID_DEC_21154;
diff --git a/hw/pci-bridge/i82801b11.c b/hw/pci-bridge/i82801b11.c
index b143f8cb79..5c40708ba8 100644
--- a/hw/pci-bridge/i82801b11.c
+++ b/hw/pci-bridge/i82801b11.c
@@ -62,10 +62,7 @@ static int i82801b11_bridge_initfn(PCIDevice *d)
 {
     int rc;
 
-    rc = pci_bridge_initfn(d, TYPE_PCI_BUS);
-    if (rc < 0) {
-        return rc;
-    }
+    pci_bridge_initfn(d, TYPE_PCI_BUS);
 
     rc = pci_bridge_ssvid_init(d, I82801ba_SSVID_OFFSET,
                                I82801ba_SSVID_SVID, I82801ba_SSVID_SSID);
diff --git a/hw/pci-bridge/ioh3420.c b/hw/pci-bridge/ioh3420.c
index 8ac4240bb1..9e048ebe35 100644
--- a/hw/pci-bridge/ioh3420.c
+++ b/hw/pci-bridge/ioh3420.c
@@ -98,11 +98,7 @@ static int ioh3420_initfn(PCIDevice *d)
     PCIESlot *s = PCIE_SLOT(d);
     int rc;
 
-    rc = pci_bridge_initfn(d, TYPE_PCIE_BUS);
-    if (rc < 0) {
-        return rc;
-    }
-
+    pci_bridge_initfn(d, TYPE_PCIE_BUS);
     pcie_port_init_reg(d);
 
     rc = pci_bridge_ssvid_init(d, IOH_EP_SSVID_OFFSET,
diff --git a/hw/pci-bridge/pci_bridge_dev.c b/hw/pci-bridge/pci_bridge_dev.c
index c9a7e2b2a3..100bb5ebf6 100644
--- a/hw/pci-bridge/pci_bridge_dev.c
+++ b/hw/pci-bridge/pci_bridge_dev.c
@@ -53,10 +53,8 @@ static int pci_bridge_dev_initfn(PCIDevice *dev)
     PCIBridgeDev *bridge_dev = PCI_BRIDGE_DEV(dev);
     int err;
 
-    err = pci_bridge_initfn(dev, TYPE_PCI_BUS);
-    if (err) {
-        goto bridge_error;
-    }
+    pci_bridge_initfn(dev, TYPE_PCI_BUS);
+
     if (bridge_dev->flags & (1 << PCI_BRIDGE_DEV_F_SHPC_REQ)) {
         dev->config[PCI_INTERRUPT_PIN] = 0x1;
         memory_region_init(&bridge_dev->bar, OBJECT(dev), "shpc-bar",
@@ -95,7 +93,7 @@ slotid_error:
     }
 shpc_error:
     pci_bridge_exitfn(dev);
-bridge_error:
+
     return err;
 }
 
diff --git a/hw/pci-bridge/xio3130_downstream.c b/hw/pci-bridge/xio3130_downstream.c
index 9eb3d8895f..c32f2712c8 100644
--- a/hw/pci-bridge/xio3130_downstream.c
+++ b/hw/pci-bridge/xio3130_downstream.c
@@ -61,11 +61,7 @@ static int xio3130_downstream_initfn(PCIDevice *d)
     PCIESlot *s = PCIE_SLOT(d);
     int rc;
 
-    rc = pci_bridge_initfn(d, TYPE_PCIE_BUS);
-    if (rc < 0) {
-        return rc;
-    }
-
+    pci_bridge_initfn(d, TYPE_PCIE_BUS);
     pcie_port_init_reg(d);
 
     rc = msi_init(d, XIO3130_MSI_OFFSET, XIO3130_MSI_NR_VECTOR,
diff --git a/hw/pci-bridge/xio3130_upstream.c b/hw/pci-bridge/xio3130_upstream.c
index 7d255a6d52..19798c09a8 100644
--- a/hw/pci-bridge/xio3130_upstream.c
+++ b/hw/pci-bridge/xio3130_upstream.c
@@ -57,11 +57,7 @@ static int xio3130_upstream_initfn(PCIDevice *d)
     PCIEPort *p = PCIE_PORT(d);
     int rc;
 
-    rc = pci_bridge_initfn(d, TYPE_PCIE_BUS);
-    if (rc < 0) {
-        return rc;
-    }
-
+    pci_bridge_initfn(d, TYPE_PCIE_BUS);
     pcie_port_init_reg(d);
 
     rc = msi_init(d, XIO3130_MSI_OFFSET, XIO3130_MSI_NR_VECTOR,
diff --git a/hw/pci-host/apb.c b/hw/pci-host/apb.c
index 75dee50bc3..aaef7bb3a1 100644
--- a/hw/pci-host/apb.c
+++ b/hw/pci-host/apb.c
@@ -635,12 +635,7 @@ static void pci_apb_set_irq(void *opaque, int irq_num, int level)
 
 static int apb_pci_bridge_initfn(PCIDevice *dev)
 {
-    int rc;
-
-    rc = pci_bridge_initfn(dev, TYPE_PCI_BUS);
-    if (rc < 0) {
-        return rc;
-    }
+    pci_bridge_initfn(dev, TYPE_PCI_BUS);
 
     /*
      * command register:
diff --git a/hw/pci/msix.c b/hw/pci/msix.c
index eb4ef113d1..537fdba747 100644
--- a/hw/pci/msix.c
+++ b/hw/pci/msix.c
@@ -80,10 +80,10 @@ static void msix_clr_pending(PCIDevice *dev, int vector)
 static bool msix_vector_masked(PCIDevice *dev, unsigned int vector, bool fmask)
 {
     unsigned offset = vector * PCI_MSIX_ENTRY_SIZE;
-    uint32_t *data = (uint32_t *)&dev->msix_table[offset + PCI_MSIX_ENTRY_DATA];
+    uint8_t *data = &dev->msix_table[offset + PCI_MSIX_ENTRY_DATA];
     /* MSIs on Xen can be remapped into pirqs. In those cases, masking
      * and unmasking go through the PV evtchn path. */
-    if (xen_is_pirq_msi(*data)) {
+    if (xen_enabled() && xen_is_pirq_msi(pci_get_long(data))) {
         return false;
     }
     return fmask || dev->msix_table[offset + PCI_MSIX_ENTRY_VECTOR_CTRL] &
diff --git a/hw/pci/pci_bridge.c b/hw/pci/pci_bridge.c
index 7eab9d57c5..3cf30bd334 100644
--- a/hw/pci/pci_bridge.c
+++ b/hw/pci/pci_bridge.c
@@ -333,7 +333,7 @@ void pci_bridge_reset(DeviceState *qdev)
 }
 
 /* default qdev initialization function for PCI-to-PCI bridge */
-int pci_bridge_initfn(PCIDevice *dev, const char *typename)
+void pci_bridge_initfn(PCIDevice *dev, const char *typename)
 {
     PCIBus *parent = dev->bus;
     PCIBridge *br = PCI_BRIDGE(dev);
@@ -379,7 +379,6 @@ int pci_bridge_initfn(PCIDevice *dev, const char *typename)
     br->windows = pci_bridge_region_init(br);
     QLIST_INIT(&sec_bus->child);
     QLIST_INSERT_HEAD(&parent->child, sec_bus, sibling);
-    return 0;
 }
 
 /* default qdev clean up function for PCI-to-PCI bridge */
diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c
index 7dff75547d..72d0c9e9ae 100644
--- a/hw/virtio/vhost.c
+++ b/hw/virtio/vhost.c
@@ -749,6 +749,27 @@ static void vhost_log_stop(MemoryListener *listener,
     /* FIXME: implement */
 }
 
+/* The vhost driver natively knows how to handle the vrings of non
+ * cross-endian legacy devices and modern devices. Only legacy devices
+ * exposed to a bi-endian guest may require the vhost driver to use a
+ * specific endianness.
+ */
+static inline bool vhost_needs_vring_endian(VirtIODevice *vdev)
+{
+    if (virtio_vdev_has_feature(vdev, VIRTIO_F_VERSION_1)) {
+        return false;
+    }
+#ifdef TARGET_IS_BIENDIAN
+#ifdef HOST_WORDS_BIGENDIAN
+    return vdev->device_endian == VIRTIO_DEVICE_ENDIAN_LITTLE;
+#else
+    return vdev->device_endian == VIRTIO_DEVICE_ENDIAN_BIG;
+#endif
+#else
+    return false;
+#endif
+}
+
 static int vhost_virtqueue_set_vring_endian_legacy(struct vhost_dev *dev,
                                                    bool is_big_endian,
                                                    int vhost_vq_index)
@@ -799,8 +820,7 @@ static int vhost_virtqueue_start(struct vhost_dev *dev,
         return -errno;
     }
 
-    if (!virtio_vdev_has_feature(vdev, VIRTIO_F_VERSION_1) &&
-        virtio_legacy_is_cross_endian(vdev)) {
+    if (vhost_needs_vring_endian(vdev)) {
         r = vhost_virtqueue_set_vring_endian_legacy(dev,
                                                     virtio_is_big_endian(vdev),
                                                     vhost_vq_index);
@@ -855,6 +875,14 @@ static int vhost_virtqueue_start(struct vhost_dev *dev,
     /* Clear and discard previous events if any. */
     event_notifier_test_and_clear(&vq->masked_notifier);
 
+    /* Init vring in unmasked state, unless guest_notifier_mask
+     * will do it later.
+     */
+    if (!vdev->use_guest_notifier_mask) {
+        /* TODO: check and handle errors. */
+        vhost_virtqueue_mask(dev, vdev, idx, false);
+    }
+
     return 0;
 
 fail_kick:
@@ -896,8 +924,7 @@ static void vhost_virtqueue_stop(struct vhost_dev *dev,
     /* In the cross-endian case, we need to reset the vring endianness to
      * native as legacy devices expect so by default.
      */
-    if (!virtio_vdev_has_feature(vdev, VIRTIO_F_VERSION_1) &&
-        virtio_legacy_is_cross_endian(vdev)) {
+    if (vhost_needs_vring_endian(vdev)) {
         r = vhost_virtqueue_set_vring_endian_legacy(dev,
                                                     !virtio_is_big_endian(vdev),
                                                     vhost_vq_index);
@@ -1148,6 +1175,7 @@ void vhost_virtqueue_mask(struct vhost_dev *hdev, VirtIODevice *vdev, int n,
     struct vhost_vring_file file;
 
     if (mask) {
+        assert(vdev->use_guest_notifier_mask);
         file.fd = event_notifier_get_fd(&hdev->vqs[index].masked_notifier);
     } else {
         file.fd = event_notifier_get_fd(virtio_queue_get_guest_notifier(vvq));
diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c
index 5494ff4a49..440776c06c 100644
--- a/hw/virtio/virtio-pci.c
+++ b/hw/virtio/virtio-pci.c
@@ -806,7 +806,7 @@ static int kvm_virtio_pci_vector_use(VirtIOPCIProxy *proxy, int nvqs)
         /* If guest supports masking, set up irqfd now.
          * Otherwise, delay until unmasked in the frontend.
          */
-        if (k->guest_notifier_mask) {
+        if (vdev->use_guest_notifier_mask && k->guest_notifier_mask) {
             ret = kvm_virtio_pci_irqfd_use(proxy, queue_no, vector);
             if (ret < 0) {
                 kvm_virtio_pci_vq_vector_release(proxy, vector);
@@ -822,7 +822,7 @@ undo:
         if (vector >= msix_nr_vectors_allocated(dev)) {
             continue;
         }
-        if (k->guest_notifier_mask) {
+        if (vdev->use_guest_notifier_mask && k->guest_notifier_mask) {
             kvm_virtio_pci_irqfd_release(proxy, queue_no, vector);
         }
         kvm_virtio_pci_vq_vector_release(proxy, vector);
@@ -849,7 +849,7 @@ static void kvm_virtio_pci_vector_release(VirtIOPCIProxy *proxy, int nvqs)
         /* If guest supports masking, clean up irqfd now.
          * Otherwise, it was cleaned when masked in the frontend.
          */
-        if (k->guest_notifier_mask) {
+        if (vdev->use_guest_notifier_mask && k->guest_notifier_mask) {
             kvm_virtio_pci_irqfd_release(proxy, queue_no, vector);
         }
         kvm_virtio_pci_vq_vector_release(proxy, vector);
@@ -882,7 +882,7 @@ static int virtio_pci_vq_vector_unmask(VirtIOPCIProxy *proxy,
     /* If guest supports masking, irqfd is already setup, unmask it.
      * Otherwise, set it up now.
      */
-    if (k->guest_notifier_mask) {
+    if (vdev->use_guest_notifier_mask && k->guest_notifier_mask) {
         k->guest_notifier_mask(vdev, queue_no, false);
         /* Test after unmasking to avoid losing events. */
         if (k->guest_notifier_pending &&
@@ -905,7 +905,7 @@ static void virtio_pci_vq_vector_mask(VirtIOPCIProxy *proxy,
     /* If guest supports masking, keep irqfd but mask it.
      * Otherwise, clean it up now.
      */ 
-    if (k->guest_notifier_mask) {
+    if (vdev->use_guest_notifier_mask && k->guest_notifier_mask) {
         k->guest_notifier_mask(vdev, queue_no, true);
     } else {
         kvm_virtio_pci_irqfd_release(proxy, queue_no, vector);
@@ -1022,7 +1022,9 @@ static int virtio_pci_set_guest_notifier(DeviceState *d, int n, bool assign,
         event_notifier_cleanup(notifier);
     }
 
-    if (!msix_enabled(&proxy->pci_dev) && vdc->guest_notifier_mask) {
+    if (!msix_enabled(&proxy->pci_dev) &&
+        vdev->use_guest_notifier_mask &&
+        vdc->guest_notifier_mask) {
         vdc->guest_notifier_mask(vdev, n, !assign);
     }
 
diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c
index 90f25451d0..e365960bd7 100644
--- a/hw/virtio/virtio.c
+++ b/hw/virtio/virtio.c
@@ -1677,6 +1677,7 @@ void virtio_init(VirtIODevice *vdev, const char *name,
     vdev->vmstate = qemu_add_vm_change_state_handler(virtio_vmstate_change,
                                                      vdev);
     vdev->device_endian = virtio_default_endian();
+    vdev->use_guest_notifier_mask = true;
 }
 
 hwaddr virtio_queue_get_desc_addr(VirtIODevice *vdev, int n)