From: Dmitry Fleytman <dfley...@redhat.com>
Virtio-net driver currently negotiates network offloads
on startup via features mechanism and have no ability to
disable and re-enable offloads later.
This patch introduced a new control command that allows
to configure device network offloads state dynamically.
The patch also introduces a new feature flag
VIRTIO_NET_F_CTRL_GUEST_OFFLOADS.
Signed-off-by: Dmitry Fleytman <dfley...@redhat.com>
---
hw/pc.h | 4 +++
hw/virtio-net.c | 97 ++++++++++++++++++++++++++++++++++++++++++++++++---------
hw/virtio-net.h | 13 ++++++++
3 files changed, 99 insertions(+), 15 deletions(-)
diff --git a/hw/pc.h b/hw/pc.h
index 8e1dd4c..7ca4698 100644
--- a/hw/pc.h
+++ b/hw/pc.h
@@ -221,6 +221,10 @@ int e820_add_entry(uint64_t, uint64_t, uint32_t);
.property = "vectors",\
/* DEV_NVECTORS_UNSPECIFIED as a uint32_t string */\
.value = stringify(0xFFFFFFFF),\
+ },{ \
+ .driver = "virtio-net-pci", \
+ .property = "ctrl_guest_offloads", \
+ .value = "off", \
},{\
.driver = "e1000",\
.property = "romfile",\
diff --git a/hw/virtio-net.c b/hw/virtio-net.c
index 5917740..a92d061 100644
--- a/hw/virtio-net.c
+++ b/hw/virtio-net.c
@@ -360,6 +360,33 @@ static uint32_t virtio_net_bad_features(VirtIODevice *vdev)
return features;
}
+static void virtio_net_apply_guest_offloads(VirtIONet *n)
+{
+ tap_set_offload(qemu_get_subqueue(n->nic, 0)->peer,
+ !!(n->curr_guest_offloads & (1ULL << VIRTIO_NET_F_GUEST_CSUM)),
+ !!(n->curr_guest_offloads & (1ULL << VIRTIO_NET_F_GUEST_TSO4)),
+ !!(n->curr_guest_offloads & (1ULL << VIRTIO_NET_F_GUEST_TSO6)),
+ !!(n->curr_guest_offloads & (1ULL << VIRTIO_NET_F_GUEST_ECN)),
+ !!(n->curr_guest_offloads & (1ULL << VIRTIO_NET_F_GUEST_UFO)));
+}
+
+static uint64_t virtio_net_guest_offloads_by_features(uint32_t features)
+{
+ static const uint64_t guest_offloads_mask =
+ (1ULL << VIRTIO_NET_F_GUEST_CSUM) |
+ (1ULL << VIRTIO_NET_F_GUEST_TSO4) |
+ (1ULL << VIRTIO_NET_F_GUEST_TSO6) |
+ (1ULL << VIRTIO_NET_F_GUEST_ECN) |
+ (1ULL << VIRTIO_NET_F_GUEST_UFO);
+
+ return guest_offloads_mask & features;
+}
+
+static inline uint64_t virtio_net_supported_guest_offloads(VirtIONet *n)
+{
+ return virtio_net_guest_offloads_by_features(n->vdev.guest_features);
+}
+
static void virtio_net_set_features(VirtIODevice *vdev, uint32_t features)
{
VirtIONet *n = to_virtio_net(vdev);
@@ -371,12 +398,9 @@ static void virtio_net_set_features(VirtIODevice *vdev,
uint32_t features)
virtio_net_set_mrg_rx_bufs(n, !!(features & (1 <<
VIRTIO_NET_F_MRG_RXBUF)));
if (n->has_vnet_hdr) {
- tap_set_offload(qemu_get_subqueue(n->nic, 0)->peer,
- (features >> VIRTIO_NET_F_GUEST_CSUM) & 1,
- (features >> VIRTIO_NET_F_GUEST_TSO4) & 1,
- (features >> VIRTIO_NET_F_GUEST_TSO6) & 1,
- (features >> VIRTIO_NET_F_GUEST_ECN) & 1,
- (features >> VIRTIO_NET_F_GUEST_UFO) & 1);
+ n->curr_guest_offloads =
+ virtio_net_guest_offloads_by_features(features);
+ virtio_net_apply_guest_offloads(n);
}
for (i = 0; i < n->max_queues; i++) {
@@ -422,6 +446,42 @@ static int virtio_net_handle_rx_mode(VirtIONet *n, uint8_t
cmd,
return VIRTIO_NET_OK;
}
+static int virtio_net_handle_offloads(VirtIONet *n, uint8_t cmd,
+ struct iovec *iov, unsigned int iov_cnt)
+{
+ uint64_t offloads;
+ size_t s;
+
+ if (!((1 << VIRTIO_NET_F_CTRL_GUEST_OFFLOADS) & n->vdev.guest_features)) {
+ return VIRTIO_NET_ERR;
+ }
+
+ s = iov_to_buf(iov, iov_cnt, 0, &offloads, sizeof(offloads));
+ if (s != sizeof(offloads)) {
+ return VIRTIO_NET_ERR;
+ }
+
+ if (cmd == VIRTIO_NET_CTRL_GUEST_OFFLOADS_SET) {
+ uint64_t supported_offloads;
+
+ if (!n->has_vnet_hdr) {
+ return VIRTIO_NET_ERR;
+ }
+
+ supported_offloads = virtio_net_supported_guest_offloads(n);
+ if (offloads & ~supported_offloads) {
+ return VIRTIO_NET_ERR;
+ }
+
+ n->curr_guest_offloads = offloads;
+ virtio_net_apply_guest_offloads(n);
+
+ return VIRTIO_NET_OK;
+ } else {
+ return VIRTIO_NET_ERR;
+ }
+}
+
static int virtio_net_handle_mac(VirtIONet *n, uint8_t cmd,
struct iovec *iov, unsigned int iov_cnt)
{
@@ -591,6 +651,8 @@ static void virtio_net_handle_ctrl(VirtIODevice *vdev,
VirtQueue *vq)
status = virtio_net_handle_vlan_table(n, ctrl.cmd, iov, iov_cnt);
} else if (ctrl.class == VIRTIO_NET_CTRL_MQ) {
status = virtio_net_handle_mq(n, ctrl.cmd, iov, iov_cnt);
+ } else if (ctrl.class == VIRTIO_NET_CTRL_GUEST_OFFLOADS) {
+ status = virtio_net_handle_offloads(n, ctrl.cmd, iov, iov_cnt);
}
s = iov_from_buf(elem.in_sg, elem.in_num, 0, &status, sizeof(status));
@@ -1100,6 +1162,10 @@ static void virtio_net_save(QEMUFile *f, void *opaque)
qemu_put_be32(f, n->vqs[i].tx_waiting);
}
}
+
+ if ((1 << VIRTIO_NET_F_CTRL_GUEST_OFFLOADS) & n->vdev.guest_features) {
+ qemu_put_be64(f, n->curr_guest_offloads);
+ }
}
static int virtio_net_load(QEMUFile *f, void *opaque, int version_id)
@@ -1156,15 +1222,6 @@ static int virtio_net_load(QEMUFile *f, void *opaque,
int version_id)
error_report("virtio-net: saved image requires vnet_hdr=on");
return -1;
}
-
- if (n->has_vnet_hdr) {
- tap_set_offload(qemu_get_queue(n->nic)->peer,
- (n->vdev.guest_features >> VIRTIO_NET_F_GUEST_CSUM) & 1,
- (n->vdev.guest_features >> VIRTIO_NET_F_GUEST_TSO4) & 1,
- (n->vdev.guest_features >> VIRTIO_NET_F_GUEST_TSO6) & 1,
- (n->vdev.guest_features >> VIRTIO_NET_F_GUEST_ECN) & 1,
- (n->vdev.guest_features >> VIRTIO_NET_F_GUEST_UFO) & 1);
- }
}
if (version_id >= 9) {
@@ -1198,6 +1255,16 @@ static int virtio_net_load(QEMUFile *f, void *opaque,
int version_id)
}
}
+ if ((1 << VIRTIO_NET_F_CTRL_GUEST_OFFLOADS) & n->vdev.guest_features) {
+ n->curr_guest_offloads = qemu_get_be64(f);
+ } else {
+ n->curr_guest_offloads = virtio_net_supported_guest_offloads(n);
+ }
+
+ if (peer_has_vnet_hdr(n)) {
+ virtio_net_apply_guest_offloads(n);
+ }
+
virtio_net_set_queues(n);
/* Find the first multicast entry in the saved MAC filter */
diff --git a/hw/virtio-net.h b/hw/virtio-net.h
index 4d1a8cd..70e362d 100644
--- a/hw/virtio-net.h
+++ b/hw/virtio-net.h
@@ -27,6 +27,8 @@
/* The feature bitmap for virtio net */
#define VIRTIO_NET_F_CSUM 0 /* Host handles pkts w/ partial csum */
#define VIRTIO_NET_F_GUEST_CSUM 1 /* Guest handles pkts w/ partial csum
*/
+#define VIRTIO_NET_F_CTRL_GUEST_OFFLOADS 2 /* Control channel offload
+ * configuration support */
#define VIRTIO_NET_F_MAC 5 /* Host has given MAC address. */
#define VIRTIO_NET_F_GSO 6 /* Host handles pkts w/ any GSO type */
#define VIRTIO_NET_F_GUEST_TSO4 7 /* Guest can handle TSOv4 in. */
@@ -182,6 +184,7 @@ typedef struct VirtIONet {
uint16_t max_queues;
uint16_t curr_queues;
size_t config_size;
+ uint64_t curr_guest_offloads;
} VirtIONet;
#define VIRTIO_NET_CTRL_MAC 1
@@ -221,6 +224,15 @@ struct virtio_net_ctrl_mq {
#define VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MIN 1
#define VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MAX 0x8000
+/*
+ * Control network offloads
+ *
+ * Dynamic offloads are available with the
+ * VIRTIO_NET_F_CTRL_GUEST_OFFLOADS feature bit.
+ */
+#define VIRTIO_NET_CTRL_GUEST_OFFLOADS 5
+ #define VIRTIO_NET_CTRL_GUEST_OFFLOADS_SET 0
+
#define DEFINE_VIRTIO_NET_FEATURES(_state, _field) \
DEFINE_VIRTIO_COMMON_FEATURES(_state, _field), \
DEFINE_PROP_BIT("csum", _state, _field, VIRTIO_NET_F_CSUM, true), \
@@ -241,6 +253,7 @@ struct virtio_net_ctrl_mq {
DEFINE_PROP_BIT("ctrl_vlan", _state, _field, VIRTIO_NET_F_CTRL_VLAN,
true), \
DEFINE_PROP_BIT("ctrl_rx_extra", _state, _field,
VIRTIO_NET_F_CTRL_RX_EXTRA, true), \
DEFINE_PROP_BIT("ctrl_mac_addr", _state, _field,
VIRTIO_NET_F_CTRL_MAC_ADDR, true), \
+ DEFINE_PROP_BIT("ctrl_guest_offloads", _state, _field,
VIRTIO_NET_F_CTRL_GUEST_OFFLOADS, true), \
DEFINE_PROP_BIT("mq", _state, _field, VIRTIO_NET_F_MQ, false)
#endif
--
1.8.1.4
