char/xillybus/xillyusb.c

106 	struct xillyfifo fifo;
223 static int fifo_write(struct xillyfifo *fifo,
230 	unsigned int writepos = fifo->writepos;
231 	unsigned int writebuf = fifo->writebuf;
235 	nmax = fifo->size - READ_ONCE(fifo->fill);
238 		unsigned int nrail = fifo->bufsize - writepos;
242 			spin_lock_irqsave(&fifo->lock, flags);
243 			fifo->fill += done;
244 			spin_unlock_irqrestore(&fifo->lock, flags);
246 			fifo->writepos = writepos;
247 			fifo->writebuf = writebuf;
255 		rc = (*copier)(fifo->mem[writebuf] + writepos, data + done, n);
266 		if (writepos == fifo->bufsize) {
270 			if (writebuf == fifo->bufnum)
276 static int fifo_read(struct xillyfifo *fifo,
283 	unsigned int readpos = fifo->readpos;
284 	unsigned int readbuf = fifo->readbuf;
289 	 * The spinlock here is necessary, because otherwise fifo->fill
292 	 * visible on this thread at the time the updated fifo->fill was.
296 	spin_lock_irqsave(&fifo->lock, flags);
297 	fill = fifo->fill;
298 	spin_unlock_irqrestore(&fifo->lock, flags);
301 		unsigned int nrail = fifo->bufsize - readpos;
305 			spin_lock_irqsave(&fifo->lock, flags);
306 			fifo->fill -= done;
307 			spin_unlock_irqrestore(&fifo->lock, flags);
309 			fifo->readpos = readpos;
310 			fifo->readbuf = readbuf;
318 		rc = (*copier)(data + done, fifo->mem[readbuf] + readpos, n);
329 		if (readpos == fifo->bufsize) {
333 			if (readbuf == fifo->bufnum)
368 static int fifo_init(struct xillyfifo *fifo,
383 		fifo->bufsize = 1 << log2_fifo_buf_size;
388 		fifo->bufsize = 1 << log2_size;
391 	fifo->bufnum = 1 << log2_bufnum;
392 	fifo->size = fifo->bufnum * fifo->bufsize;
393 	fifo->buf_order = buf_order;
395 	fifo->mem = kmalloc_array(fifo->bufnum, sizeof(void *), GFP_KERNEL);
397 	if (!fifo->mem)
400 	for (i = 0; i < fifo->bufnum; i++) {
401 		fifo->mem[i] = (void *)
404 		if (!fifo->mem[i])
408 	fifo->fill = 0;
409 	fifo->readpos = 0;
410 	fifo->readbuf = 0;
411 	fifo->writepos = 0;
412 	fifo->writebuf = 0;
413 	spin_lock_init(&fifo->lock);
414 	init_waitqueue_head(&fifo->waitq);
419 		free_pages((unsigned long)fifo->mem[i], buf_order);
421 	kfree(fifo->mem);
422 	fifo->mem = NULL;
432 static void fifo_mem_release(struct xillyfifo *fifo)
436 	if (!fifo->mem)
439 	for (i = 0; i < fifo->bufnum; i++)
440 		free_pages((unsigned long)fifo->mem[i], fifo->buf_order);
442 	kfree(fifo->mem);
462  * Note that endpoint_dealloc() also frees fifo memory (if allocated), even
470 	fifo_mem_release(&ep->fifo);
601 			wake_up_interruptible(&chan->out_ep->fifo.waitq);
610 	wake_up_interruptible(&xdev->msg_ep->fifo.waitq);
640 				  struct xillyfifo *fifo)
643 	chan->in_fifo = fifo;
768 	struct xillyfifo *fifo = &ep->fifo;
783 	fill = READ_ONCE(fifo->fill) & ep->fill_mask;
826 		count = fifo_read(&ep->fifo, xb->buf, max_read, xilly_memcpy);
873 		wake_up_interruptible(&fifo->waitq);
946 	struct xillyfifo *fifo;
1005 		fifo = chan->in_fifo;
1007 		if (unlikely(!fifo))
1010 		if (bytes != fifo_write(fifo, p, bytes, xilly_memcpy)) {
1015 		wake_up_interruptible(&fifo->waitq);
1075 	struct xillyfifo *fifo = &ep->fifo;
1094 	while (wait_event_interruptible(fifo->waitq,
1095 					fifo->fill <= (fifo->size - 8) ||
1104 	fifo_write(fifo, (void *)msg, 8, xilly_memcpy);
1311 		rc = fifo_init(&out_ep->fifo, chan->out_log2_fifo_size);
1439 	struct xillyfifo *fifo = chan->in_fifo;
1462 		rc = fifo_read(fifo, (__force void *)userbuf + bytes_done,
1481 		fifo_checkpoint_bytes = chan->in_consumed_bytes + fifo->size;
1514 		    (leap > (fifo->size >> 3) ||
1539 			if (READ_ONCE(fifo->fill))
1571 			 * fifo->waitq is awaken.
1576 				(fifo->waitq,
1577 				 fifo->fill || !chan->read_data_ok,
1587 				(fifo->waitq,
1588 				 fifo->fill || !chan->read_data_ok);
1598 	    !READ_ONCE(fifo->fill))
1650 	struct xillyfifo *fifo = &chan->out_ep->fifo;
1667 		rc = fifo_write(fifo, (__force void *)userbuf, count,
1679 		    (fifo->waitq,
1680 		     fifo->fill != fifo->size || xdev->error)) {
1858 		poll_wait(filp, &chan->out_ep->fifo.waitq, wait);
1887 	    (READ_ONCE(chan->out_ep->fifo.fill) != chan->out_ep->fifo.size))
1914 	if (fifo_init(&xdev->msg_ep->fifo, 13)) /* 8 kiB */
2185 	struct xillyfifo *fifo = &msg_ep->fifo;
2206 	rc = wait_event_interruptible_timeout(fifo->waitq,