In case of live migration with legacy guest (without
VIRTIO_NET_F_GUEST_ANNOUNCE)
a message is added between QEMU and the vhost client/backend.
This message provides the RARP content, prepared by QEMU, to the vhost
client/backend.
The vhost client/backend is responsible to send the RARP.
Signed-off-by: Thibaut Collet <thibaut.col...@6wind.com>
---
docs/specs/vhost-user.txt | 16 ++++++++++++++++
hw/net/vhost_net.c | 8 ++++++++
hw/virtio/vhost-user.c | 11 ++++++++++-
linux-headers/linux/vhost.h | 9 +++++++++
4 files changed, 43 insertions(+), 1 deletion(-)
diff --git a/docs/specs/vhost-user.txt b/docs/specs/vhost-user.txt
index 2c8e934..ef5d475 100644
--- a/docs/specs/vhost-user.txt
+++ b/docs/specs/vhost-user.txt
@@ -97,6 +97,7 @@ typedef struct VhostUserMsg {
uint64_t u64;
struct vhost_vring_state state;
struct vhost_vring_addr addr;
+ struct vhost_inject_rarp rarp;
VhostUserMemory memory;
};
} QEMU_PACKED VhostUserMsg;
@@ -132,6 +133,12 @@ Multi queue support
The protocol supports multiple queues by setting all index fields in the sent
messages to a properly calculated value.
+Live migration support
+----------------------
+The protocol supports live migration. GARP from the migrated guest is done
+through the VIRTIO_NET_F_GUEST_ANNOUNCE mechanism for guest that supports it or
+through RARP.
+
Message types
-------------
@@ -269,3 +276,12 @@ Message types
Bits (0-7) of the payload contain the vring index. Bit 8 is the
invalid FD flag. This flag is set when there is no file descriptor
in the ancillary data.
+
+ * VHOST_USER_NET_INJECT_RARP
+
+ Id: 15
+ Master payload: rarp content
+
+ Provide the RARP message to send to the guest after a live migration.
This
+ message is sent only for guest that does not support
+ VIRTIO_NET_F_GUEST_ANNOUNCE.
diff --git a/hw/net/vhost_net.c b/hw/net/vhost_net.c
index 4a42325..f66d48d 100644
--- a/hw/net/vhost_net.c
+++ b/hw/net/vhost_net.c
@@ -369,10 +369,18 @@ void vhost_net_stop(VirtIODevice *dev, NetClientState
*ncs,
void vhost_net_inject_rarp(struct vhost_net *net, const uint8_t *buf, size_t
size)
{
+ struct vhost_inject_rarp inject_rarp;
+ memcpy(&inject_rarp.rarp, buf, size);
+
if ((net->dev.acked_features & (1 << VIRTIO_NET_F_GUEST_ANNOUNCE)) == 0) {
+ const VhostOps *vhost_ops = net->dev.vhost_ops;
+ int r;
+
fprintf(stderr,
"Warning: Guest with no VIRTIO_NET_F_GUEST_ANNOUNCE support.
RARP must be sent by vhost-user backend\n");
fflush(stderr);
+ r = vhost_ops->vhost_call(&net->dev, VHOST_NET_INJECT_RARP,
&inject_rarp);
+ assert(r >= 0);
}
}
diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c
index d6f2163..2e752ab 100644
--- a/hw/virtio/vhost-user.c
+++ b/hw/virtio/vhost-user.c
@@ -41,6 +41,7 @@ typedef enum VhostUserRequest {
VHOST_USER_SET_VRING_KICK = 12,
VHOST_USER_SET_VRING_CALL = 13,
VHOST_USER_SET_VRING_ERR = 14,
+ VHOST_USER_NET_INJECT_RARP = 15,
VHOST_USER_MAX
} VhostUserRequest;
@@ -70,6 +71,7 @@ typedef struct VhostUserMsg {
uint64_t u64;
struct vhost_vring_state state;
struct vhost_vring_addr addr;
+ struct vhost_inject_rarp rarp;
VhostUserMemory memory;
};
} QEMU_PACKED VhostUserMsg;
@@ -104,7 +106,8 @@ static unsigned long int
ioctl_to_vhost_user_request[VHOST_USER_MAX] = {
VHOST_GET_VRING_BASE, /* VHOST_USER_GET_VRING_BASE */
VHOST_SET_VRING_KICK, /* VHOST_USER_SET_VRING_KICK */
VHOST_SET_VRING_CALL, /* VHOST_USER_SET_VRING_CALL */
- VHOST_SET_VRING_ERR /* VHOST_USER_SET_VRING_ERR */
+ VHOST_SET_VRING_ERR, /* VHOST_USER_SET_VRING_ERR */
+ VHOST_NET_INJECT_RARP /* VHOST_USER_NET_INJECT_RARP */
};
static VhostUserRequest vhost_user_request_translate(unsigned long int request)
@@ -287,6 +290,12 @@ static int vhost_user_call(struct vhost_dev *dev, unsigned
long int request,
msg.u64 |= VHOST_USER_VRING_NOFD_MASK;
}
break;
+
+ case VHOST_NET_INJECT_RARP:
+ memcpy(&msg.rarp, arg, sizeof(struct vhost_inject_rarp));
+ msg.size = sizeof(struct vhost_inject_rarp);
+ break;
+
default:
error_report("vhost-user trying to send unhandled ioctl");
return -1;
diff --git a/linux-headers/linux/vhost.h b/linux-headers/linux/vhost.h
index c656f61..1920134 100644
--- a/linux-headers/linux/vhost.h
+++ b/linux-headers/linux/vhost.h
@@ -63,6 +63,10 @@ struct vhost_memory {
struct vhost_memory_region regions[0];
};
+struct vhost_inject_rarp {
+ __u8 rarp[60];
+};
+
/* ioctls */
#define VHOST_VIRTIO 0xAF
@@ -121,6 +125,11 @@ struct vhost_memory {
* device. This can be used to stop the ring (e.g. for migration). */
#define VHOST_NET_SET_BACKEND _IOW(VHOST_VIRTIO, 0x30, struct vhost_vring_file)
+/* Inject a RARP in case of live migration for guest that does not support
+ * VIRTIO_NET_F_GUEST_ANNOUNCE */
+#define VHOST_NET_INJECT_RARP _IOW(VHOST_VIRTIO, 0x31, struct
vhost_inject_rarp)
+
+
/* Feature bits */
/* Log all write descriptors. Can be changed while device is active. */
#define VHOST_F_LOG_ALL 26
--
1.7.10.4
