OpenE2K
/
linux
6
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

lguest: notify on empty 

This is the lguest implementation of the VIRTIO_F_NOTIFY_ON_EMPTY feature.
It is currently only published for network devices, but it is turned on for
everyone.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This commit is contained in:
Rusty Russell 2008-05-30 15:09:46 -05:00
parent b4f68be6c5
commit 2088761152
1 changed files with 10 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

12
Documentation/lguest/lguest.c
View File

@ -157,6 +157,9 @@ struct virtqueue
/* The routine to call when the Guest pings us. */
void (*handle_output)(int fd, struct virtqueue *me);
/* Outstanding buffers */
unsigned int inflight;
};
/* Remember the arguments to the program so we can "reboot" */
@ -702,6 +705,7 @@ static unsigned get_vq_desc(struct virtqueue *vq,
errx(1, "Looped descriptor");
} while ((i = next_desc(vq, i)) != vq->vring.num);
vq->inflight++;
return head;
}
@ -719,6 +723,7 @@ static void add_used(struct virtqueue *vq, unsigned int head, int len)
/* Make sure buffer is written before we update index. */
wmb();
vq->vring.used->idx++;
vq->inflight--;
}
/* This actually sends the interrupt for this virtqueue */
@ -726,8 +731,9 @@ static void trigger_irq(int fd, struct virtqueue *vq)
{
unsigned long buf[] = { LHREQ_IRQ, vq->config.irq };
/* If they don't want an interrupt, don't send one. */
if (vq->vring.avail->flags & VRING_AVAIL_F_NO_INTERRUPT)
/* If they don't want an interrupt, don't send one, unless empty. */
if ((vq->vring.avail->flags & VRING_AVAIL_F_NO_INTERRUPT)
&& vq->inflight)
return;
/* Send the Guest an interrupt tell them we used something up. */
@ -1107,6 +1113,7 @@ static void add_virtqueue(struct device *dev, unsigned int num_descs,
vq->next = NULL;
vq->last_avail_idx = 0;
vq->dev = dev;
vq->inflight = 0;
/* Initialize the configuration. */
vq->config.num = num_descs;
@ -1368,6 +1375,7 @@ static void setup_tun_net(const char *arg)
/* Tell Guest what MAC address to use. */
add_feature(dev, VIRTIO_NET_F_MAC);
add_feature(dev, VIRTIO_F_NOTIFY_ON_EMPTY);
set_config(dev, sizeof(conf), &conf);
/* We don't need the socket any more; setup is done. */