@@ -123,6 +123,7 @@ static void vring_init(struct vring *vr, unsigned int num, void *p,
/* We're running with interrupts off anyways, so don't bother */
vr->used->flags = VRING_USED_F_NO_NOTIFY;
vr->used->idx = 0;
+ vr->used_idx = 0;
debug_print_addr("init vr", vr);
}
@@ -150,8 +151,6 @@ static void vring_send_buf(struct vring *vr, void *p, int len, int flags)
if (!(flags & VRING_DESC_F_NEXT)) {
vr->avail->idx++;
}
-
- vr->used->idx = vr->next_idx;
}
static u64 get_clock(void)
@@ -180,7 +179,8 @@ static int vring_wait_reply(struct vring *vr, int timeout)
struct subchannel_id schid = vr->schid;
int r = 0;
- while (vr->used->idx == vr->next_idx) {
+ /* Wait until the used index has moved. */
+ while (vr->used->idx == vr->used_idx) {
vring_notify(schid);
if (timeout && (get_second() >= target_second)) {
r = 1;
@@ -189,6 +189,7 @@ static int vring_wait_reply(struct vring *vr, int timeout)
yield();
}
+ vr->used_idx = vr->used->idx;
vr->next_idx = 0;
vr->desc[0].len = 0;
vr->desc[0].flags = 0;
@@ -115,6 +115,7 @@ struct vring_used {
struct vring {
unsigned int num;
int next_idx;
+ int used_idx;
struct vring_desc *desc;
struct vring_avail *avail;
struct vring_used *used;