On Thu, Mar 28, 2013 at 12:00:59PM +0200, Dmitry Fleytman wrote:
> From: Dmitry Fleytman <dfleytma@xxxxxxxxxx>
>
> Virtio-net driver currently negotiates network offloads
> on startup via features mechanism and have no ability to
> change offloads state 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_OFFLD.
>
> Signed-off-by: Dmitry Fleytman <dfleytma@xxxxxxxxxx>
> ---
> hw/virtio-net.c | 111 ++++++++++++++++++++++++++++++++++++++++++++++++--------
> hw/virtio-net.h | 19 ++++++++++
> 2 files changed, 115 insertions(+), 15 deletions(-)
>
> diff --git a/hw/virtio-net.c b/hw/virtio-net.c
> index 5917740..a016823 100644
> --- a/hw/virtio-net.c
> +++ b/hw/virtio-net.c
> @@ -360,6 +360,48 @@ static uint32_t virtio_net_bad_features(VirtIODevice *vdev)
> return features;
> }
>
> +static void virtio_net_apply_offloads(VirtIONet *n)
> +{
> + tap_set_offload(qemu_get_subqueue(n->nic, 0)->peer,
> + !!(n->curr_offloads & VIRTIO_NET_OFFLOAD_GUEST_CSUM),
> + !!(n->curr_offloads & VIRTIO_NET_OFFLOAD_GUEST_TSO4),
> + !!(n->curr_offloads & VIRTIO_NET_OFFLOAD_GUEST_TSO6),
> + !!(n->curr_offloads & VIRTIO_NET_OFFLOAD_GUEST_ECN),
> + !!(n->curr_offloads & VIRTIO_NET_OFFLOAD_GUEST_UFO));
> +}
> +
> +static uint32_t virtio_net_offloads_by_features(uint32_t features)
> +{
> + uint32_t offloads = 0;
> +
> + if ((1 << VIRTIO_NET_F_GUEST_CSUM) & features) {
> + offloads |= VIRTIO_NET_OFFLOAD_GUEST_CSUM;
> + }
> +
> + if ((1 << VIRTIO_NET_F_GUEST_TSO4) & features) {
> + offloads |= VIRTIO_NET_OFFLOAD_GUEST_TSO4;
> + }
> +
> + if ((1 << VIRTIO_NET_F_GUEST_TSO6) & features) {
> + offloads |= VIRTIO_NET_OFFLOAD_GUEST_TSO6;
> + }
> +
> + if ((1 << VIRTIO_NET_F_GUEST_ECN) & features) {
> + offloads |= VIRTIO_NET_OFFLOAD_GUEST_ECN;
> + }
> +
> + if ((1 << VIRTIO_NET_F_GUEST_UFO) & features) {
> + offloads |= VIRTIO_NET_OFFLOAD_GUEST_UFO;
> + }
> +
> + return offloads;
> +}
> +
> +static inline uint32_t virtio_net_supported_offloads(VirtIONet *n)
> +{
> + return virtio_net_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 +413,8 @@ 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_offloads = virtio_net_offloads_by_features(features);
> + virtio_net_apply_offloads(n);
> }
>
> for (i = 0; i < n->max_queues; i++) {
> @@ -422,6 +460,42 @@ 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)
> +{
> + uint32_t offloads;
> + size_t s;
> +
> + if (!((1 << VIRTIO_NET_F_CTRL_GUEST_OFFLD) & 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) {
> + uint32_t supported_offloads;
> +
> + if (!n->has_vnet_hdr) {
> + return VIRTIO_NET_ERR;
> + }
> +
> + supported_offloads = virtio_net_supported_offloads(n);
> + if (offloads & ~supported_offloads) {
> + return VIRTIO_NET_ERR;
> + }
> +
> + n->curr_offloads = offloads;
> + virtio_net_apply_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 +665,8 @@ 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 +1176,10 @@ 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_OFFLD) & n->vdev.guest_features) {
> + qemu_put_be32(f, n->curr_offloads);
> + }
> }
>
> static int virtio_net_load(QEMUFile *f, void *opaque, int version_id)
> @@ -1156,15 +1236,6 @@ 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 +1269,16 @@ static int virtio_net_load(QEMUFile *f, void *opaque, int version_id)
> }
> }
>
> + if ((1 << VIRTIO_NET_F_CTRL_GUEST_OFFLD) & n->vdev.guest_features) {
> + n->curr_offloads = qemu_get_be32(f);
> + } else {
> + n->curr_offloads = virtio_net_supported_offloads(n);
> + }
> +
> + if (peer_has_vnet_hdr(n)) {
> + virtio_net_apply_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..002d526 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_OFFLD 2 /* Control channel offload
It's very long anyway, so let's make it the full
VIRTIO_NET_F_CTRL_GUEST_OFFLOADS to match the command name.
> + * 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;
> + uint32_t curr_offloads;
> } VirtIONet;
>
> #define VIRTIO_NET_CTRL_MAC 1
> @@ -221,6 +224,21 @@ 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_OFFLD feature bit.
> + */
> +#define VIRTIO_NET_CTRL_GUEST_OFFLOADS 5
> + #define VIRTIO_NET_CTRL_GUEST_OFFLOADS_SET 0
> +
> +#define VIRTIO_NET_OFFLOAD_GUEST_CSUM 1
> +#define VIRTIO_NET_OFFLOAD_GUEST_TSO4 2
> +#define VIRTIO_NET_OFFLOAD_GUEST_TSO6 4
> +#define VIRTIO_NET_OFFLOAD_GUEST_ECN 8
> +#define VIRTIO_NET_OFFLOAD_GUEST_UFO 16
> +
> #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 +259,7 @@ 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_gst_offld", _state, _field, VIRTIO_NET_F_CTRL_GUEST_OFFLD, true), \
> DEFINE_PROP_BIT("mq", _state, _field, VIRTIO_NET_F_MQ, false)
>
> #endif
Looks good. Better to replace ctrl_gst_offld by ctrl_guest_offloads.
Also need to patch hw/pc.h with compat macros so that
the feature is disabled for old machine types.
> --
> 1.8.1.4
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