lsi: extract lsi_find_by_tag

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
This commit is contained in:
Paolo Bonzini 2011-04-18 12:01:45 +02:00
parent ad2d30f79d
commit 11257187e1

View File

@ -652,38 +652,51 @@ static void lsi_reselect(LSIState *s, lsi_request *p)
}
}
static lsi_request *lsi_find_by_tag(LSIState *s, uint32_t tag)
{
lsi_request *p;
QTAILQ_FOREACH(p, &s->queue, next) {
if (p->tag == tag) {
return p;
}
}
return NULL;
}
/* Record that data is available for a queued command. Returns zero if
the device was reselected, nonzero if the IO is deferred. */
static int lsi_queue_tag(LSIState *s, uint32_t tag, uint32_t arg)
{
lsi_request *p;
QTAILQ_FOREACH(p, &s->queue, next) {
if (p->tag == tag) {
if (p->pending) {
BADF("Multiple IO pending for tag %d\n", tag);
}
p->pending = arg;
/* Reselect if waiting for it, or if reselection triggers an IRQ
and the bus is free.
Since no interrupt stacking is implemented in the emulation, it
is also required that there are no pending interrupts waiting
for service from the device driver. */
if (s->waiting == 1 ||
(lsi_irq_on_rsl(s) && !(s->scntl1 & LSI_SCNTL1_CON) &&
!(s->istat0 & (LSI_ISTAT0_SIP | LSI_ISTAT0_DIP)))) {
/* Reselect device. */
lsi_reselect(s, p);
return 0;
} else {
DPRINTF("Queueing IO tag=0x%x\n", tag);
p->pending = arg;
return 1;
}
}
p = lsi_find_by_tag(s, tag);
if (!p) {
BADF("IO with unknown tag %d\n", tag);
return 1;
}
if (p->pending) {
BADF("Multiple IO pending for tag %d\n", tag);
}
p->pending = arg;
/* Reselect if waiting for it, or if reselection triggers an IRQ
and the bus is free.
Since no interrupt stacking is implemented in the emulation, it
is also required that there are no pending interrupts waiting
for service from the device driver. */
if (s->waiting == 1 ||
(lsi_irq_on_rsl(s) && !(s->scntl1 & LSI_SCNTL1_CON) &&
!(s->istat0 & (LSI_ISTAT0_SIP | LSI_ISTAT0_DIP)))) {
/* Reselect device. */
lsi_reselect(s, p);
return 0;
} else {
DPRINTF("Queueing IO tag=0x%x\n", tag);
p->pending = arg;
return 1;
}
BADF("IO with unknown tag %d\n", tag);
return 1;
}
/* Callback to indicate that the SCSI layer has completed a transfer. */