void blkfront_sync(struct blkfront_dev *dev)
{
unsigned long flags;
DEFINE_WAIT(w);
if (dev->info.mode == O_RDWR) {
if (dev->info.barrier == 1)
blkfront_push_operation(dev, BLKIF_OP_WRITE_BARRIER, 0);
if (dev->info.flush == 1)
blkfront_push_operation(dev, BLKIF_OP_FLUSH_DISKCACHE, 0);
}
/* Note: This won't finish if another thread enqueues requests. */
local_irq_save(flags);
while (1) {
blkfront_aio_poll(dev);
if (RING_FREE_REQUESTS(&dev->ring) == RING_SIZE(&dev->ring))
break;
minios_add_waiter(w, blkfront_queue);
local_irq_restore(flags);
minios_schedule();
local_irq_save(flags);
}
minios_remove_waiter(w, blkfront_queue);
local_irq_restore(flags);
}
static struct xenbus_event *await_event(struct xenbus_event_queue *queue)
{
struct xenbus_event *event;
DEFINE_WAIT(w);
spin_lock(&xenbus_req_lock);
while (!(event = remove_event(queue))) {
minios_add_waiter(w, queue->waitq);
spin_unlock(&xenbus_req_lock);
minios_wait(w);
spin_lock(&xenbus_req_lock);
}
minios_remove_waiter(w, queue->waitq);
spin_unlock(&xenbus_req_lock);
return event;
}
static void blkfront_wait_slot(struct blkfront_dev *dev)
{
/* Wait for a slot */
if (RING_FULL(&dev->ring)) {
unsigned long flags;
DEFINE_WAIT(w);
local_irq_save(flags);
while (1) {
blkfront_aio_poll(dev);
if (!RING_FULL(&dev->ring))
break;
/* Really no slot, go to sleep. */
minios_add_waiter(w, blkfront_queue);
local_irq_restore(flags);
minios_schedule();
local_irq_save(flags);
}
minios_remove_waiter(w, blkfront_queue);
local_irq_restore(flags);
}
}
void blkfront_io(struct blkfront_aiocb *aiocbp, int write)
{
unsigned long flags;
DEFINE_WAIT(w);
ASSERT(!aiocbp->aio_cb);
aiocbp->aio_cb = blkfront_aio_cb;
blkfront_aio(aiocbp, write);
aiocbp->data = NULL;
local_irq_save(flags);
while (1) {
blkfront_aio_poll(aiocbp->aio_dev);
if (aiocbp->data)
break;
minios_add_waiter(w, blkfront_queue);
local_irq_restore(flags);
minios_schedule();
local_irq_save(flags);
}
minios_remove_waiter(w, blkfront_queue);
local_irq_restore(flags);
}
