[S390] qdio: improve inbound buffer acknowledgement

- Use automatic acknowledgement of incoming buffers in QEBSM mode
- Move ACK for non-QEBSM mode always to the newest buffer to prevent
  a race with qdio_stop_polling
- Remove the polling spinlock, the upper layer drivers return new buffers
  in the same code path and could not run in parallel
- Don't flood the error log in case of no-target-buffer-empty
- In handle_inbound we check if we would overwrite an ACK'ed buffer, if so
  advance the pointer to the oldest ACK'ed buffer so we don't overwrite an
  empty buffer in qdio_stop_polling

Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 0 insertions, 1 deletions

diff --git a/drivers/s390/cio/qdio_setup.c b/drivers/s390/cio/qdio_setup.c
index 7323799b2ce3..18d54fc21ce9 100644
--- a/drivers/s390/cio/qdio_setup.c
+++ b/drivers/s390/cio/qdio_setup.c
@@ -167,7 +167,6 @@ static void setup_queues(struct qdio_irq *irq_ptr,
                 setup_queues_misc(q, irq_ptr, qdio_init->input_handler, i);
 
                 q->is_input_q = 1;
-                spin_lock_init(&q->u.in.lock);
                 setup_storage_lists(q, irq_ptr, input_sbal_array, i);
                 input_sbal_array += QDIO_MAX_BUFFERS_PER_Q;