s390/qdio: clean up AOB handling

I've stumbled over this too many times now... AOBs are only ever used on
Output Queues. So in qdio_kick_handler(), move the call to their handler
into the Output-only path, and get rid of the convoluted contains_aobs()
helper. No functional change.

While at it, also remove
1. the unused sbal_state->aob field. For processing an async completion,
   upper-layer drivers get their AOB pointer from the CQ buffer.
2. an unused EXPORT for qdio_allocate_aob(). External users would have
   no way of passing an allocated AOB back into qdio.ko anyways...
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

arch/s390/include/asm/qdio.h

@@ -252,13 +252,11 @@ struct slsb {
  *   (for communication with upper layer programs)
  *   (only required for use with completion queues)
  * @flags: flags indicating state of buffer
- * @aob: pointer to QAOB used for the particular SBAL
  * @user: pointer to upper layer program's state information related to SBAL
  *        (stored in user1 data of QAOB)
  */
 struct qdio_outbuf_state {
 	u8 flags;
-	struct qaob *aob;
 	void *user;
 };
 

drivers/s390/cio/qdio_main.c

@@ -595,19 +595,11 @@ static inline int qdio_inbound_q_done(struct qdio_q *q)
 		return 0;
 }
 
-static inline int contains_aobs(struct qdio_q *q)
-{
-	return !q->is_input_q && q->u.out.use_cq;
-}
-
 static inline void qdio_handle_aobs(struct qdio_q *q, int start, int count)
 {
 	unsigned char state = 0;
 	int j, b = start;
 
-	if (!contains_aobs(q))
-		return;
-
 	for (j = 0; j < count; ++j) {
 		get_buf_state(q, b, &state, 0);
 		if (state == SLSB_P_OUTPUT_PENDING) {
@@ -618,8 +610,6 @@ static inline void qdio_handle_aobs(struct qdio_q *q, int start, int count)
 			q->u.out.sbal_state[b].flags |=
 				QDIO_OUTBUF_STATE_FLAG_PENDING;
 			q->u.out.aobs[b] = NULL;
-		} else if (state == SLSB_P_OUTPUT_EMPTY) {
-			q->u.out.sbal_state[b].aob = NULL;
 		}
 		b = next_buf(b);
 	}
@@ -638,7 +628,6 @@ static inline unsigned long qdio_aob_for_buffer(struct qdio_output_q *q,
 		q->aobs[bufnr] = aob;
 	}
 	if (q->aobs[bufnr]) {
-		q->sbal_state[bufnr].aob = q->aobs[bufnr];
 		q->aobs[bufnr]->user1 = (u64) q->sbal_state[bufnr].user;
 		phys_aob = virt_to_phys(q->aobs[bufnr]);
 		WARN_ON_ONCE(phys_aob & 0xFF);
@@ -666,9 +655,9 @@ static void qdio_kick_handler(struct qdio_q *q)
 		qperf_inc(q, outbound_handler);
 		DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "koh: s:%02x c:%02x",
 			      start, count);
-	}
-
+		if (q->u.out.use_cq)
 			qdio_handle_aobs(q, start, count);
+	}
 
 	q->handler(q->irq_ptr->cdev, q->qdio_error, q->nr, start, count,
 		   q->irq_ptr->int_parm);

drivers/s390/cio/qdio_setup.c

@@ -27,7 +27,6 @@ struct qaob *qdio_allocate_aob(void)
 {
 	return kmem_cache_zalloc(qdio_aob_cache, GFP_ATOMIC);
 }
-EXPORT_SYMBOL_GPL(qdio_allocate_aob);
 
 void qdio_release_aob(struct qaob *aob)
 {