aboutsummaryrefslogtreecommitdiff
path: root/docs
diff options
context:
space:
mode:
authorThibaut Collet <thibaut.collet@6wind.com>2015-10-09 17:17:32 +0200
committerMichael S. Tsirkin <mst@redhat.com>2015-10-22 14:34:49 +0300
commit3e866365e1eb6bcfa2d01c21debb05b9e47a47f7 (patch)
treee729ff5a9a19d482984eb8e930c065ffa0d7b634 /docs
parentf6f56291de879827766d17b172465d4377ad2c11 (diff)
vhost user: add rarp sending after live migration for legacy guest
A new vhost user message is added to allow QEMU to ask to vhost user backend to broadcast a fake RARP after live migration for guest without GUEST_ANNOUNCE capability. This new message is sent only if the backend supports the new VHOST_USER_PROTOCOL_F_RARP protocol feature. The payload of this new message is the MAC address of the guest (not known by the backend). The MAC address is copied in the first 6 bytes of a u64 to avoid to create a new payload message type. This new message has no equivalent ioctl so a new callback is added in the userOps structure to send the request. Upon reception of this new message the vhost user backend must generate and broadcast a fake RARP request to notify the migration is terminated. Signed-off-by: Thibaut Collet <thibaut.collet@6wind.com> [Rebased and fixed checkpatch errors - Marc-André] Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Tested-by: Thibaut Collet <thibaut.collet@6wind.com>
Diffstat (limited to 'docs')
-rw-r--r--docs/specs/vhost-user.txt15
1 files changed, 15 insertions, 0 deletions
diff --git a/docs/specs/vhost-user.txt b/docs/specs/vhost-user.txt
index e0292a0e65..e0d71e27e6 100644
--- a/docs/specs/vhost-user.txt
+++ b/docs/specs/vhost-user.txt
@@ -194,6 +194,7 @@ Protocol features
#define VHOST_USER_PROTOCOL_F_MQ 0
#define VHOST_USER_PROTOCOL_F_LOG_SHMFD 1
+#define VHOST_USER_PROTOCOL_F_RARP 2
Message types
-------------
@@ -381,3 +382,17 @@ Message types
Master payload: vring state description
Signal slave to enable or disable corresponding vring.
+
+ * VHOST_USER_SEND_RARP
+
+ Id: 19
+ Equivalent ioctl: N/A
+ Master payload: u64
+
+ Ask vhost user backend to broadcast a fake RARP to notify the migration
+ is terminated for guest that does not support GUEST_ANNOUNCE.
+ Only legal if feature bit VHOST_USER_F_PROTOCOL_FEATURES is present in
+ VHOST_USER_GET_FEATURES and protocol feature bit VHOST_USER_PROTOCOL_F_RARP
+ is present in VHOST_USER_GET_PROTOCOL_FEATURES.
+ The first 6 bytes of the payload contain the mac address of the guest to
+ allow the vhost user backend to construct and broadcast the fake RARP.