Commit 04310324 authored Jun 03, 2019 by Julian Wiedmann Committed by Heiko Carstens Jun 07, 2019

s390/qdio: handle PENDING state for QEBSM devices



When a CQ-enabled device uses QEBSM for SBAL state inspection,
get_buf_states() can return the PENDING state for an Output Queue.
get_outbound_buffer_frontier() isn't prepared for this, and any PENDING
buffer will permanently stall all further completion processing on this
Queue.

This isn't a concern for non-QEBSM devices, as get_buf_states() for such
devices will manually turn PENDING buffers into EMPTY ones.

Fixes: 104ea556 ("qdio: support asynchronous delivery of storage blocks")
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>

parent 6887560c

drivers/s390/cio/qdio_main.c

+1 −0

Original line number	Diff line number	Diff line
		@@ -736,6 +736,7 @@ static int get_outbound_buffer_frontier(struct qdio_q *q, unsigned int start)

		switch (state) {
		case SLSB_P_OUTPUT_EMPTY:
		case SLSB_P_OUTPUT_PENDING:
		/* the adapter got it */
		DBF_DEV_EVENT(DBF_INFO, q->irq_ptr,
		"out empty:%1d %02x", q->nr, count);