net: add offloading support to netmap backend

Whit this patch, the netmap backend supports TSO/UFO/CSUM
offloadings, and accepts the virtio-net header, similarly to what
happens with TAP. The offloading callbacks in the NetClientInfo
interface have been implemented.

Signed-off-by: Vincenzo Maffione <v.maffione@gmail.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This commit is contained in:
Vincenzo Maffione 2014-02-06 17:02:20 +01:00 committed by Stefan Hajnoczi
parent 3bac80d31a
commit f6c65bfb93

View File

@ -31,6 +31,7 @@
#include <net/netmap_user.h>
#include "net/net.h"
#include "net/tap.h"
#include "clients.h"
#include "sysemu/sysemu.h"
#include "qemu/error-report.h"
@ -54,6 +55,7 @@ typedef struct NetmapState {
bool read_poll;
bool write_poll;
struct iovec iov[IOV_MAX];
int vnet_hdr_len; /* Current virtio-net header length. */
} NetmapState;
#define D(format, ...) \
@ -274,7 +276,7 @@ static ssize_t netmap_receive_iov(NetClientState *nc,
return iov_size(iov, iovcnt);
}
i = ring->cur;
last = i = ring->cur;
avail = ring->avail;
if (avail < iovcnt) {
@ -394,6 +396,63 @@ static void netmap_cleanup(NetClientState *nc)
s->me.fd = -1;
}
/* Offloading manipulation support callbacks. */
static bool netmap_has_ufo(NetClientState *nc)
{
return true;
}
static bool netmap_has_vnet_hdr(NetClientState *nc)
{
return true;
}
static bool netmap_has_vnet_hdr_len(NetClientState *nc, int len)
{
return len == 0 || len == sizeof(struct virtio_net_hdr) ||
len == sizeof(struct virtio_net_hdr_mrg_rxbuf);
}
static void netmap_using_vnet_hdr(NetClientState *nc, bool enable)
{
}
static void netmap_set_vnet_hdr_len(NetClientState *nc, int len)
{
NetmapState *s = DO_UPCAST(NetmapState, nc, nc);
int err;
struct nmreq req;
/* Issue a NETMAP_BDG_VNET_HDR command to change the virtio-net header
* length for the netmap adapter associated to 'me->ifname'.
*/
memset(&req, 0, sizeof(req));
pstrcpy(req.nr_name, sizeof(req.nr_name), s->me.ifname);
req.nr_version = NETMAP_API;
req.nr_cmd = NETMAP_BDG_VNET_HDR;
req.nr_arg1 = len;
err = ioctl(s->me.fd, NIOCREGIF, &req);
if (err) {
error_report("Unable to execute NETMAP_BDG_VNET_HDR on %s: %s",
s->me.ifname, strerror(errno));
} else {
/* Keep track of the current length. */
s->vnet_hdr_len = len;
}
}
static void netmap_set_offload(NetClientState *nc, int csum, int tso4, int tso6,
int ecn, int ufo)
{
NetmapState *s = DO_UPCAST(NetmapState, nc, nc);
/* Setting a virtio-net header length greater than zero automatically
* enables the offloadings.
*/
if (!s->vnet_hdr_len) {
netmap_set_vnet_hdr_len(nc, sizeof(struct virtio_net_hdr));
}
}
/* NetClientInfo methods */
static NetClientInfo net_netmap_info = {
@ -403,6 +462,12 @@ static NetClientInfo net_netmap_info = {
.receive_iov = netmap_receive_iov,
.poll = netmap_poll,
.cleanup = netmap_cleanup,
.has_ufo = netmap_has_ufo,
.has_vnet_hdr = netmap_has_vnet_hdr,
.has_vnet_hdr_len = netmap_has_vnet_hdr_len,
.using_vnet_hdr = netmap_using_vnet_hdr,
.set_offload = netmap_set_offload,
.set_vnet_hdr_len = netmap_set_vnet_hdr_len,
};
/* The exported init function
@ -428,6 +493,7 @@ int net_init_netmap(const NetClientOptions *opts,
nc = qemu_new_net_client(&net_netmap_info, peer, "netmap", name);
s = DO_UPCAST(NetmapState, nc, nc);
s->me = me;
s->vnet_hdr_len = 0;
netmap_read_poll(s, true); /* Initially only poll for reads. */
return 0;