[S390] qdio: prevent handling of buffers if count is zero

Exit do_QDIO early if the buffer count is zero to prevent side effects
in the following functions.

Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This commit is contained in:
Jan Glauber 2011-03-23 10:16:01 +01:00 committed by Martin Schwidefsky
parent 4cc69531f9
commit 9a26513eb6

View File

@ -1508,7 +1508,8 @@ int do_QDIO(struct ccw_device *cdev, unsigned int callflags,
if (irq_ptr->state != QDIO_IRQ_STATE_ACTIVE)
return -EBUSY;
if (!count)
return 0;
if (callflags & QDIO_FLAG_SYNC_INPUT)
return handle_inbound(irq_ptr->input_qs[q_nr],
callflags, bufnr, count);