[Qemu-devel] [PATCH v2 8/9] vhost-user: send log shm fd along with log_base

["Marc-André Lureau" <marcandre.lureau@redhat.com>]

Send the shm for the dirty pages logging if the backend support
VHOST_USER_PROTOCOL_F_LOG_SHMFD.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
---
 hw/virtio/vhost-user.c | 16 ++++++++++++++--
 hw/virtio/vhost.c      |  5 +++--
 2 files changed, 17 insertions(+), 4 deletions(-)

diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c
index 21ecbcd..b2f46a9 100644
--- a/hw/virtio/vhost-user.c
+++ b/hw/virtio/vhost-user.c
@@ -26,7 +26,9 @@
 #define VHOST_MEMORY_MAX_NREGIONS    8
 
 #define VHOST_USER_F_PROTOCOL_FEATURES 30
-#define VHOST_USER_PROTOCOL_FEATURE_MASK 0x0ULL
+
+#define VHOST_USER_PROTOCOL_FEATURE_MASK 0x1ULL
+#define VHOST_USER_PROTOCOL_F_LOG_SHMFD 0
 
 typedef enum VhostUserRequest {
     VHOST_USER_NONE = 0,
@@ -215,8 +217,18 @@ static int vhost_user_call(struct vhost_dev *dev,
         need_reply = 1;
         break;
 
+    case VHOST_USER_SET_LOG_BASE: {
+        struct vhost_log *log = va_arg(ap, struct vhost_log *);
+
+        if (__virtio_has_feature(dev->protocol_features,
+                                 VHOST_USER_PROTOCOL_F_LOG_SHMFD) &&
+            log->fd != -1) {
+            fds[fd_num++] = log->fd;
+        }
+    }
+        /* fall through */
+
     case VHOST_USER_SET_FEATURES:
-    case VHOST_USER_SET_LOG_BASE:
         msg.u64 = *((__u64 *) arg);
         msg.size = sizeof(m.u64);
         break;
diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c
index 057d548..ed8b1a5 100644
--- a/hw/virtio/vhost.c
+++ b/hw/virtio/vhost.c
@@ -359,7 +359,7 @@ static inline void vhost_dev_log_resize(struct vhost_dev* dev, uint64_t size)
 
     /* inform backend of log switching, this must be done before
        releasing the current log, to ensure no logging is lost */
-    r = dev->vhost_ops->vhost_call(dev, VHOST_SET_LOG_BASE, &log_base);
+    r = dev->vhost_ops->vhost_call(dev, VHOST_SET_LOG_BASE, &log_base, log);
     assert(r >= 0);
     vhost_log_put(dev, true);
     dev->log = log;
@@ -1167,7 +1167,8 @@ int vhost_dev_start(struct vhost_dev *hdev, VirtIODevice *vdev)
         hdev->log = vhost_log_get(hdev->log_size, share);
         log_base = (uintptr_t)hdev->log->log;
         r = hdev->vhost_ops->vhost_call(hdev, VHOST_SET_LOG_BASE,
-                                        hdev->log_size ? &log_base : NULL);
+                                        hdev->log_size ? &log_base : NULL,
+                                        hdev->log);
         if (r < 0) {
             r = -errno;
             goto fail_log;
-- 
2.4.3