According to VirtIO standard, "The driver MUST follow
the VIRTIO_NET_CTRL_MAC_TABLE_SET command by a le32 number,
followed by that number of non-multicast MAC addresses,
followed by another le32 number, followed by that number
of multicast addresses."
Considering that these data is not stored in contiguous memory,
this patch refactors vhost_vdpa_net_load_cmd() to accept
scattered data, eliminating the need for an addtional data copy or
packing the data into s->cvq_cmd_out_buffer outside of
vhost_vdpa_net_load_cmd().
Signed-off-by: Hawkins Jiawei <yin31...@gmail.com>
---
v2:
- refactor vhost_vdpa_load_cmd() to accept iovec suggested by
Eugenio
net/vhost-vdpa.c | 42 ++++++++++++++++++++++++++++++++----------
1 file changed, 32 insertions(+), 10 deletions(-)
diff --git a/net/vhost-vdpa.c b/net/vhost-vdpa.c
index 6f6a5c6df6..0bd1c7817c 100644
--- a/net/vhost-vdpa.c
+++ b/net/vhost-vdpa.c
@@ -620,29 +620,43 @@ static ssize_t vhost_vdpa_net_cvq_add(VhostVDPAState *s,
size_t out_len,
}
static ssize_t vhost_vdpa_net_load_cmd(VhostVDPAState *s, uint8_t class,
- uint8_t cmd, const void *data,
- size_t data_size)
+ uint8_t cmd, const struct iovec *data,
+ size_t data_len)
{
const struct virtio_net_ctrl_hdr ctrl = {
.class = class,
.cmd = cmd,
};
+ void *cursor = s->cvq_cmd_out_buffer;
- assert(data_size < vhost_vdpa_net_cvq_cmd_page_len() - sizeof(ctrl));
+ /* pack the CVQ command header */
+ assert(sizeof(ctrl) < vhost_vdpa_net_cvq_cmd_page_len() -
+ (cursor - s->cvq_cmd_out_buffer));
+ memcpy(cursor, &ctrl, sizeof(ctrl));
+ cursor += sizeof(ctrl);
- memcpy(s->cvq_cmd_out_buffer, &ctrl, sizeof(ctrl));
- memcpy(s->cvq_cmd_out_buffer + sizeof(ctrl), data, data_size);
+ /* pack the CVQ command command-specific-data */
+ for (int i = 0; i < data_len; ++i) {
+ assert(data[i].iov_len < vhost_vdpa_net_cvq_cmd_page_len() -
+ (cursor - s->cvq_cmd_out_buffer));
+ memcpy(cursor, data[i].iov_base, data[i].iov_len);
+ cursor += data[i].iov_len;
+ }
- return vhost_vdpa_net_cvq_add(s, sizeof(ctrl) + data_size,
+ return vhost_vdpa_net_cvq_add(s, cursor - s->cvq_cmd_out_buffer,
sizeof(virtio_net_ctrl_ack));
}
static int vhost_vdpa_net_load_mac(VhostVDPAState *s, const VirtIONet *n)
{
if (virtio_vdev_has_feature(&n->parent_obj, VIRTIO_NET_F_CTRL_MAC_ADDR)) {
+ const struct iovec data = {
+ .iov_base = (void *)n->mac,
+ .iov_len = sizeof(n->mac),
+ };
ssize_t dev_written = vhost_vdpa_net_load_cmd(s, VIRTIO_NET_CTRL_MAC,
VIRTIO_NET_CTRL_MAC_ADDR_SET,
- n->mac, sizeof(n->mac));
+ &data, 1);
if (unlikely(dev_written < 0)) {
return dev_written;
}
@@ -665,9 +679,13 @@ static int vhost_vdpa_net_load_mq(VhostVDPAState *s,
}
mq.virtqueue_pairs = cpu_to_le16(n->curr_queue_pairs);
+ const struct iovec data = {
+ .iov_base = &mq,
+ .iov_len = sizeof(mq),
+ };
dev_written = vhost_vdpa_net_load_cmd(s, VIRTIO_NET_CTRL_MQ,
- VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET, &mq,
- sizeof(mq));
+ VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET,
+ &data, 1);
if (unlikely(dev_written < 0)) {
return dev_written;
}
@@ -706,9 +724,13 @@ static int vhost_vdpa_net_load_offloads(VhostVDPAState *s,
}
offloads = cpu_to_le64(n->curr_guest_offloads);
+ const struct iovec data = {
+ .iov_base = &offloads,
+ .iov_len = sizeof(offloads),
+ };
dev_written = vhost_vdpa_net_load_cmd(s, VIRTIO_NET_CTRL_GUEST_OFFLOADS,
VIRTIO_NET_CTRL_GUEST_OFFLOADS_SET,
- &offloads, sizeof(offloads));
+ &data, 1);
if (unlikely(dev_written < 0)) {
return dev_written;
}
--
2.25.1
