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.col...@6wind.com> --- docs/specs/vhost-user.txt | 15 +++++++++++++++ hw/net/vhost_net.c | 16 ++++++++++++++++ hw/virtio/vhost-backend.c | 3 ++- hw/virtio/vhost-user.c | 32 ++++++++++++++++++++++++++++++-- include/hw/virtio/vhost-backend.h | 2 ++ include/net/vhost_net.h | 1 + net/vhost-user.c | 23 +++++++++++++++++++++-- 7 files changed, 87 insertions(+), 5 deletions(-) diff --git a/docs/specs/vhost-user.txt b/docs/specs/vhost-user.txt index c2d2e2a..8c05301 100644 --- a/docs/specs/vhost-user.txt +++ b/docs/specs/vhost-user.txt @@ -140,6 +140,7 @@ Protocol features ----------------- #define VHOST_USER_PROTOCOL_F_LOG_SHMFD 0 +#define VHOST_USER_PROTOCOL_F_RARP 1 Message types ------------- @@ -308,6 +309,20 @@ Message types invalid FD flag. This flag is set when there is no file descriptor in the ancillary data. + * VHOST_USER_SEND_RARP + + Id: 17 + 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. + Migration --------- diff --git a/hw/net/vhost_net.c b/hw/net/vhost_net.c index 9850520..cbcb6dd 100644 --- a/hw/net/vhost_net.c +++ b/hw/net/vhost_net.c @@ -383,6 +383,17 @@ void vhost_net_cleanup(struct vhost_net *net) g_free(net); } +int vhost_net_notify_migration_done(struct vhost_net *net, char* mac_addr) +{ + const VhostOps *vhost_ops = net->dev.vhost_ops; + int r = -1; + + if (vhost_ops->vhost_backend_migration_done) + r = vhost_ops->vhost_backend_migration_done(&net->dev, mac_addr); + + return r; +} + bool vhost_net_virtqueue_pending(VHostNetState *net, int idx) { return vhost_virtqueue_pending(&net->dev, idx); @@ -456,6 +467,11 @@ void vhost_net_virtqueue_mask(VHostNetState *net, VirtIODevice *dev, { } +int vhost_net_notify_migration_done(struct vhost_net *net) +{ + return -1; +} + VHostNetState *get_vhost_net(NetClientState *nc) { return 0; diff --git a/hw/virtio/vhost-backend.c b/hw/virtio/vhost-backend.c index 4d68a27..09a5d67 100644 --- a/hw/virtio/vhost-backend.c +++ b/hw/virtio/vhost-backend.c @@ -46,7 +46,8 @@ static const VhostOps kernel_ops = { .backend_type = VHOST_BACKEND_TYPE_KERNEL, .vhost_call = vhost_kernel_call, .vhost_backend_init = vhost_kernel_init, - .vhost_backend_cleanup = vhost_kernel_cleanup + .vhost_backend_cleanup = vhost_kernel_cleanup, + .vhost_backend_migration_done = NULL }; int vhost_set_backend_type(struct vhost_dev *dev, VhostBackendType backend_type) diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c index fe75618..aa65cd5 100644 --- a/hw/virtio/vhost-user.c +++ b/hw/virtio/vhost-user.c @@ -10,6 +10,7 @@ #include "hw/virtio/vhost.h" #include "hw/virtio/vhost-backend.h" +#include "hw/virtio/virtio-net.h" #include "sysemu/char.h" #include "sysemu/kvm.h" #include "qemu/error-report.h" @@ -27,8 +28,9 @@ #define VHOST_USER_F_PROTOCOL_FEATURES 30 -#define VHOST_USER_PROTOCOL_FEATURE_MASK 0x1ULL +#define VHOST_USER_PROTOCOL_FEATURE_MASK 0x3ULL #define VHOST_USER_PROTOCOL_F_LOG_SHMFD 0 +#define VHOST_USER_PROTOCOL_F_RARP 1 typedef enum VhostUserRequest { VHOST_USER_NONE = 0, @@ -48,6 +50,7 @@ typedef enum VhostUserRequest { VHOST_USER_SET_VRING_ERR = 14, VHOST_USER_GET_PROTOCOL_FEATURES = 15, VHOST_USER_SET_PROTOCOL_FEATURES = 16, + VHOST_USER_SEND_RARP = 17, VHOST_USER_MAX } VhostUserRequest; @@ -409,9 +412,34 @@ static int vhost_user_cleanup(struct vhost_dev *dev) return 0; } +static int vhost_user_migration_done(struct vhost_dev *dev, char* mac_addr) +{ + VhostUserMsg msg = { 0 }; + int err; + + assert(dev->vhost_ops->backend_type == VHOST_BACKEND_TYPE_USER); + + /* If guest supports GUEST_ANNOUNCE do nothing */ + if (__virtio_has_feature(dev->acked_features, VIRTIO_NET_F_GUEST_ANNOUNCE)) + return 0; + + /* if backend supports VHOST_USER_PROTOCOL_F_RARP ask it to send the RARP */ + if (__virtio_has_feature(dev->protocol_features, VHOST_USER_PROTOCOL_F_RARP)) { + msg.request = VHOST_USER_SEND_RARP; + msg.flags = VHOST_USER_VERSION; + memcpy((char*) &msg.u64, mac_addr, 6); + msg.size = sizeof(m.u64); + + err = vhost_user_write(dev, &msg, NULL, 0); + return err; + } + return -1; +} + const VhostOps user_ops = { .backend_type = VHOST_BACKEND_TYPE_USER, .vhost_call = vhost_user_call, .vhost_backend_init = vhost_user_init, - .vhost_backend_cleanup = vhost_user_cleanup + .vhost_backend_cleanup = vhost_user_cleanup, + .vhost_backend_migration_done = vhost_user_migration_done }; diff --git a/include/hw/virtio/vhost-backend.h b/include/hw/virtio/vhost-backend.h index e472f29..5c8a440 100644 --- a/include/hw/virtio/vhost-backend.h +++ b/include/hw/virtio/vhost-backend.h @@ -24,12 +24,14 @@ typedef int (*vhost_call)(struct vhost_dev *dev, unsigned long int request, void *arg); typedef int (*vhost_backend_init)(struct vhost_dev *dev, void *opaque); typedef int (*vhost_backend_cleanup)(struct vhost_dev *dev); +typedef int (*vhost_backend_migration_done)(struct vhost_dev *dev, char* mac_addr); typedef struct VhostOps { VhostBackendType backend_type; vhost_call vhost_call; vhost_backend_init vhost_backend_init; vhost_backend_cleanup vhost_backend_cleanup; + vhost_backend_migration_done vhost_backend_migration_done; } VhostOps; extern const VhostOps user_ops; diff --git a/include/net/vhost_net.h b/include/net/vhost_net.h index 840d4b1..8e5dfd4 100644 --- a/include/net/vhost_net.h +++ b/include/net/vhost_net.h @@ -26,5 +26,6 @@ void vhost_net_ack_features(VHostNetState *net, uint64_t features); bool vhost_net_virtqueue_pending(VHostNetState *net, int n); void vhost_net_virtqueue_mask(VHostNetState *net, VirtIODevice *dev, int idx, bool mask); +int vhost_net_notify_migration_done(VHostNetState *net, char* mac_addr); VHostNetState *get_vhost_net(NetClientState *nc); #endif diff --git a/net/vhost-user.c b/net/vhost-user.c index 1b1c626..2489eeb 100644 --- a/net/vhost-user.c +++ b/net/vhost-user.c @@ -68,9 +68,28 @@ static void vhost_user_stop(VhostUserState *s) static ssize_t vhost_user_receive(NetClientState *nc, const uint8_t *buf, size_t size) { - /* Discard the request that is received and managed by backend - * by an other way. + /* In case of RARP (message size is 60) notify backup to send a fake RARP. + This fake RARP will be sent by backend only for guest + without GUEST_ANNOUNCE capability. */ + if (size == 60) { + VhostUserState *s = DO_UPCAST(VhostUserState, nc, nc); + int r; + static int display_rarp_failure = 1; + char mac_addr[6]; + + /* extract guest mac address from the RARP message */ + memcpy(mac_addr, &buf[6], 6); + + r = vhost_net_notify_migration_done(s->vhost_net, mac_addr); + + if ((r != 0) && (display_rarp_failure)) { + fprintf(stderr, + "Vhost user backend fails to broadcast fake RARP\n"); + fflush(stderr); + display_rarp_failure = 0; + } + } return size; } -- 1.7.10.4