Signed-off-by: Eugenio Pérez <eperezma@xxxxxxxxxx>
---
hw/virtio/vhost-sw-lm-ring.h | 26 +++++++++
include/hw/virtio/vhost.h | 3 ++
hw/virtio/vhost-sw-lm-ring.c | 60 +++++++++++++++++++++
hw/virtio/vhost.c | 100 +++++++++++++++++++++++++++++++++--
hw/virtio/meson.build | 2 +-
5 files changed, 187 insertions(+), 4 deletions(-)
create mode 100644 hw/virtio/vhost-sw-lm-ring.h
create mode 100644 hw/virtio/vhost-sw-lm-ring.c
diff --git a/hw/virtio/vhost-sw-lm-ring.h b/hw/virtio/vhost-sw-lm-ring.h
new file mode 100644
index 0000000000..86dc081b93
--- /dev/null
+++ b/hw/virtio/vhost-sw-lm-ring.h
@@ -0,0 +1,26 @@
+/*
+ * vhost software live migration ring
+ *
+ * SPDX-FileCopyrightText: Red Hat, Inc. 2020
+ * SPDX-FileContributor: Author: Eugenio Pérez <eperezma@xxxxxxxxxx>
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#ifndef VHOST_SW_LM_RING_H
+#define VHOST_SW_LM_RING_H
+
+#include "qemu/osdep.h"
+
+#include "hw/virtio/virtio.h"
+#include "hw/virtio/vhost.h"
+
+typedef struct VhostShadowVirtqueue VhostShadowVirtqueue;
+
+bool vhost_vring_kick(VhostShadowVirtqueue *vq);
+
+VhostShadowVirtqueue *vhost_sw_lm_shadow_vq(struct vhost_dev *dev, int idx);
+
+void vhost_sw_lm_shadow_vq_free(VhostShadowVirtqueue *vq);
+
+#endif
diff --git a/include/hw/virtio/vhost.h b/include/hw/virtio/vhost.h
index b5b7496537..93cc3f1ae3 100644
--- a/include/hw/virtio/vhost.h
+++ b/include/hw/virtio/vhost.h
@@ -54,6 +54,8 @@ struct vhost_iommu {
QLIST_ENTRY(vhost_iommu) iommu_next;
};
+typedef struct VhostShadowVirtqueue VhostShadowVirtqueue;
+
typedef struct VhostDevConfigOps {
/* Vhost device config space changed callback
*/
@@ -83,6 +85,7 @@ struct vhost_dev {
bool started;
bool log_enabled;
uint64_t log_size;
+ VhostShadowVirtqueue *sw_lm_shadow_vq[2];
VirtIOHandleOutput sw_lm_vq_handler;
Error *migration_blocker;
const VhostOps *vhost_ops;
diff --git a/hw/virtio/vhost-sw-lm-ring.c b/hw/virtio/vhost-sw-lm-ring.c
new file mode 100644
index 0000000000..0192e77831
--- /dev/null
+++ b/hw/virtio/vhost-sw-lm-ring.c
@@ -0,0 +1,60 @@
+/*
+ * vhost software live migration ring
+ *
+ * SPDX-FileCopyrightText: Red Hat, Inc. 2020
+ * SPDX-FileContributor: Author: Eugenio Pérez <eperezma@xxxxxxxxxx>
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#include "hw/virtio/vhost-sw-lm-ring.h"
+#include "hw/virtio/vhost.h"
+
+#include "standard-headers/linux/vhost_types.h"
+#include "standard-headers/linux/virtio_ring.h"
+
+#include "qemu/event_notifier.h"
+
+typedef struct VhostShadowVirtqueue {
+ EventNotifier hdev_notifier;
+ VirtQueue *vq;
+} VhostShadowVirtqueue;
+
+static inline bool vhost_vring_should_kick(VhostShadowVirtqueue *vq)
+{
+ return virtio_queue_get_used_notify_split(vq->vq);
+}
+
+bool vhost_vring_kick(VhostShadowVirtqueue *vq)
+{
+ return vhost_vring_should_kick(vq) ? event_notifier_set(&vq->hdev_notifier)
+ : true;
+}
+
+VhostShadowVirtqueue *vhost_sw_lm_shadow_vq(struct vhost_dev *dev, int idx)
+{
+ struct vhost_vring_file file = {
+ .index = idx
+ };
+ VirtQueue *vq = virtio_get_queue(dev->vdev, idx);
+ VhostShadowVirtqueue *svq;
+ int r;
+
+ svq = g_new0(VhostShadowVirtqueue, 1);
+ svq->vq = vq;
+
+ r = event_notifier_init(&svq->hdev_notifier, 0);
+ assert(r == 0);
+
+ file.fd = event_notifier_get_fd(&svq->hdev_notifier);
+ r = dev->vhost_ops->vhost_set_vring_kick(dev, &file);
+ assert(r == 0);
+
+ return svq;
+}
+
+void vhost_sw_lm_shadow_vq_free(VhostShadowVirtqueue *vq)
+{
+ event_notifier_cleanup(&vq->hdev_notifier);
+ g_free(vq);
+}
diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c
index 9cbd52a7f1..a55b684b5f 100644
--- a/hw/virtio/vhost.c
+++ b/hw/virtio/vhost.c
@@ -13,6 +13,8 @@
* GNU GPL, version 2 or (at your option) any later version.
*/
+#include "hw/virtio/vhost-sw-lm-ring.h"
+
#include "qemu/osdep.h"
#include "qapi/error.h"
#include "hw/virtio/vhost.h"
@@ -61,6 +63,20 @@ bool vhost_has_free_slot(void)
return slots_limit > used_memslots;
}
+static struct vhost_dev *vhost_dev_from_virtio(const VirtIODevice *vdev)
+{
+ struct vhost_dev *hdev;
+
+ QLIST_FOREACH(hdev, &vhost_devices, entry) {
+ if (hdev->vdev == vdev) {
+ return hdev;
+ }
+ }
+
+ assert(hdev);
+ return NULL;
+}
+
static bool vhost_dev_can_log(const struct vhost_dev *hdev)
{
return hdev->features & (0x1ULL << VHOST_F_LOG_ALL);
@@ -148,6 +164,12 @@ static int vhost_sync_dirty_bitmap(struct vhost_dev *dev,
return 0;
}
+static void vhost_log_sync_nop(MemoryListener *listener,
+ MemoryRegionSection *section)
+{
+ return;
+}
+
static void vhost_log_sync(MemoryListener *listener,
MemoryRegionSection *section)
{
@@ -928,6 +950,71 @@ static void vhost_log_global_stop(MemoryListener *listener)
}
}
+static void handle_sw_lm_vq(VirtIODevice *vdev, VirtQueue *vq)
+{
+ struct vhost_dev *hdev = vhost_dev_from_virtio(vdev);
+ uint16_t idx = virtio_get_queue_index(vq);
+
+ VhostShadowVirtqueue *svq = hdev->sw_lm_shadow_vq[idx];
+
+ vhost_vring_kick(svq);
+}
+
+static int vhost_sw_live_migration_stop(struct vhost_dev *dev)
+{
+ int idx;
+
+ vhost_dev_enable_notifiers(dev, dev->vdev);
+ for (idx = 0; idx < dev->nvqs; ++idx) {
+ vhost_sw_lm_shadow_vq_free(dev->sw_lm_shadow_vq[idx]);
+ }
+
+ return 0;
+}
+
+static int vhost_sw_live_migration_start(struct vhost_dev *dev)
+{
+ int idx;
+
+ for (idx = 0; idx < dev->nvqs; ++idx) {
+ dev->sw_lm_shadow_vq[idx] = vhost_sw_lm_shadow_vq(dev, idx);
+ }
+
+ vhost_dev_disable_notifiers(dev, dev->vdev);
+
+ return 0;
+}
+
+static int vhost_sw_live_migration_enable(struct vhost_dev *dev,
+ bool enable_lm)
+{
+ if (enable_lm) {
+ return vhost_sw_live_migration_start(dev);
+ } else {
+ return vhost_sw_live_migration_stop(dev);
+ }
+}
+
+static void vhost_sw_lm_global_start(MemoryListener *listener)
+{
+ int r;
+
+ r = vhost_migration_log(listener, true, vhost_sw_live_migration_enable);
+ if (r < 0) {
+ abort();
+ }
+}
+
+static void vhost_sw_lm_global_stop(MemoryListener *listener)
+{
+ int r;
+
+ r = vhost_migration_log(listener, false, vhost_sw_live_migration_enable);
+ if (r < 0) {
+ abort();
+ }
+}
+
static void vhost_log_start(MemoryListener *listener,
MemoryRegionSection *section,
int old, int new)
@@ -1334,9 +1421,14 @@ int vhost_dev_init(struct vhost_dev *hdev, void *opaque,
.region_nop = vhost_region_addnop,
.log_start = vhost_log_start,
.log_stop = vhost_log_stop,
- .log_sync = vhost_log_sync,
- .log_global_start = vhost_log_global_start,
- .log_global_stop = vhost_log_global_stop,
+ .log_sync = !vhost_dev_can_log(hdev) ?
+ vhost_log_sync_nop :
+ vhost_log_sync,
+ .log_global_start = !vhost_dev_can_log(hdev) ?
+ vhost_sw_lm_global_start :
+ vhost_log_global_start,
+ .log_global_stop = !vhost_dev_can_log(hdev) ? vhost_sw_lm_global_stop :
+ vhost_log_global_stop,
.eventfd_add = vhost_eventfd_add,
.eventfd_del = vhost_eventfd_del,
.priority = 10
@@ -1364,6 +1456,8 @@ int vhost_dev_init(struct vhost_dev *hdev, void *opaque,
error_free(hdev->migration_blocker);
goto fail_busyloop;
}
+ } else {
+ hdev->sw_lm_vq_handler = handle_sw_lm_vq;
}
hdev->mem = g_malloc0(offsetof(struct vhost_memory, regions));
diff --git a/hw/virtio/meson.build b/hw/virtio/meson.build
index fbff9bc9d4..17419cb13e 100644
--- a/hw/virtio/meson.build
+++ b/hw/virtio/meson.build
@@ -11,7 +11,7 @@ softmmu_ss.add(when: 'CONFIG_ALL', if_true: files('vhost-stub.c'))
virtio_ss = ss.source_set()
virtio_ss.add(files('virtio.c'))
-virtio_ss.add(when: 'CONFIG_VHOST', if_true: files('vhost.c', 'vhost-backend.c'))
+virtio_ss.add(when: 'CONFIG_VHOST', if_true: files('vhost.c', 'vhost-backend.c', 'vhost-sw-lm-ring.c'))
virtio_ss.add(when: 'CONFIG_VHOST_USER', if_true: files('vhost-user.c'))
virtio_ss.add(when: 'CONFIG_VHOST_VDPA', if_true: files('vhost-vdpa.c'))
virtio_ss.add(when: 'CONFIG_VIRTIO_BALLOON', if_true: files('virtio-balloon.c'))
--
2.18.4
