>
> "Gonglei (Arei)" <arei.gong...@huawei.com> wrote:
> >> Hi,
> >>
> >> > Anything bigger than 16bytes, no? And that is the whole point that we
> >> > are talking about? Or the 16bytes that we are using can be at any place
> >> > on the buffer?
> >>
> >> Yes. It's a ring buffer, with rptr pointing to the first used element
> >> and wptr pointing to the first free element.
> >>
> >> So, what we need is a function to move the content we are interested
> >> (between rptr and wptr) in to the head of the ring buffer, set rptr to
> >> 0, set wptr to count. We obviously need to do that in post_load(), but
> >> as I've noticed meanwhile also in pre_save, otherwise old qemu will get
> >> things wrong in case the buffer is wrapped (rptr > wptr).
> >>
> > Hi, Gerd. Maybe we just need to do in post_load(). Such as the follow code:
> >
> > static int ps2_kbd_post_load(void* opaque, int version_id)
> > {
> > PS2KbdState *s = (PS2KbdState*)opaque;
>
> cast not needed.
This is the original code, I don't change it. Maybe I should post the diff
file, Sorry.
>
> > PS2State *ps2 = &s->common;
> > PS2Queue *q = &ps2->queue;
> > int size;
> > int i;
> >
> > if (version_id == 2)
> > s->scancode_set=2;
> > /* the new version id for this patch */
> > if (version_id == 4) {
> > return 0;
> > }
> > /* set the useful data buffer queue size, < PS2_QUEUE_SIZE */
> > size = MIN(q->count, PS2_QUEUE_SIZE);
> > printf(" ==kbd: rptr: %d, wptr: %d, count: %d, size: %d\n", q->rptr,
> q->wptr, q->count, size);
> > for (i = 0; i < size; i++) {
> > /* move the queue elements to the start of data array */
> > q->data[i] = q->data[q->rptr];
>
> It is me, or this don't work if the destination and source regions
> overlap? Yes, it depens on how it overlaps.
Good catch, Juan, Thanks. It should use a temp data array to save the q->data[]
value,
Such as below:
int size;
int i;
int tmp_data[PS2_QUEUE_SIZE];
/* set the useful data buffer queue size, < PS2_QUEUE_SIZE */
size = MIN(q->count, PS2_QUEUE_SIZE);
printf(" ==kbd: rptr: %d, wptr: %d, count: %d, size: %d\n", q->rptr,
q->wptr, q->count, size);
for (i = 0; i < size; i++) {
/* move the queue elements to the tmp data array */
tmp_data[i] = q->data[q->rptr];
if (++q->rptr == 256) {
q->rptr = 0;
}
}
for (i = 0; i < size; i++) {
/* move the queue elements to the start of data array */
q->data[i] = tmp_data[i];
}
/* reset rptr/wptr/count */
q->rptr = 0;
q->wptr = size;
q->count = size;
s->update_irq(s->update_arg, q->count != 0);
return 0;
}
Best regards,
-Gonglei
