tap: support enabling or disabling a queue

This patch introduce a new bit - enabled in TAPState which tracks whether a
specific queue/fd is enabled. The tap/fd is enabled during initialization and
could be enabled/disabled by tap_enalbe() and tap_disable() which calls platform
specific helpers to do the real work. Polling of a tap fd can only done when
the tap was enabled.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
This commit is contained in:
Jason Wang 2013-01-30 19:12:32 +08:00 committed by Anthony Liguori
parent 94fdc6d030
commit 16dbaf905b
3 changed files with 52 additions and 3 deletions

View File

@ -35,6 +35,8 @@ int tap_has_vnet_hdr_len(NetClientState *nc, int len);
void tap_using_vnet_hdr(NetClientState *nc, bool using_vnet_hdr);
void tap_set_offload(NetClientState *nc, int csum, int tso4, int tso6, int ecn, int ufo);
void tap_set_vnet_hdr_len(NetClientState *nc, int len);
int tap_enable(NetClientState *nc);
int tap_disable(NetClientState *nc);
int tap_get_fd(NetClientState *nc);

View File

@ -764,3 +764,13 @@ void tap_set_vnet_hdr_len(NetClientState *nc, int len)
{
abort();
}
int tap_enable(NetClientState *nc)
{
abort();
}
int tap_disable(NetClientState *nc)
{
abort();
}

View File

@ -59,6 +59,7 @@ typedef struct TAPState {
bool write_poll;
bool using_vnet_hdr;
bool has_ufo;
bool enabled;
VHostNetState *vhost_net;
unsigned host_vnet_hdr_len;
} TAPState;
@ -72,9 +73,9 @@ static void tap_writable(void *opaque);
static void tap_update_fd_handler(TAPState *s)
{
qemu_set_fd_handler2(s->fd,
s->read_poll ? tap_can_send : NULL,
s->read_poll ? tap_send : NULL,
s->write_poll ? tap_writable : NULL,
s->read_poll && s->enabled ? tap_can_send : NULL,
s->read_poll && s->enabled ? tap_send : NULL,
s->write_poll && s->enabled ? tap_writable : NULL,
s);
}
@ -337,6 +338,7 @@ static TAPState *net_tap_fd_init(NetClientState *peer,
s->host_vnet_hdr_len = vnet_hdr ? sizeof(struct virtio_net_hdr) : 0;
s->using_vnet_hdr = false;
s->has_ufo = tap_probe_has_ufo(s->fd);
s->enabled = true;
tap_set_offload(&s->nc, 0, 0, 0, 0, 0);
/*
* Make sure host header length is set correctly in tap:
@ -735,3 +737,38 @@ VHostNetState *tap_get_vhost_net(NetClientState *nc)
assert(nc->info->type == NET_CLIENT_OPTIONS_KIND_TAP);
return s->vhost_net;
}
int tap_enable(NetClientState *nc)
{
TAPState *s = DO_UPCAST(TAPState, nc, nc);
int ret;
if (s->enabled) {
return 0;
} else {
ret = tap_fd_enable(s->fd);
if (ret == 0) {
s->enabled = true;
tap_update_fd_handler(s);
}
return ret;
}
}
int tap_disable(NetClientState *nc)
{
TAPState *s = DO_UPCAST(TAPState, nc, nc);
int ret;
if (s->enabled == 0) {
return 0;
} else {
ret = tap_fd_disable(s->fd);
if (ret == 0) {
qemu_purge_queued_packets(nc);
s->enabled = false;
tap_update_fd_handler(s);
}
return ret;
}
}