qdio: support forced signal adapter indications

This patch ensures that signal adapter commands are issued if they are
indicated to be required.

Signed-off-by: Einar Lueck <[email protected]>
Signed-off-by: Jan Glauber <[email protected]>
Signed-off-by: Frank Blaschka <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

Author: [email protected]

arch/s390/include/asm/qdio.h

@@ -279,6 +279,16 @@ struct qdio_outbuf_state {
 
 #define CHSC_AC1_INITIATE_INPUTQ	0x80
 
+
+/* qdio adapter-characteristics-1 flag */
+#define AC1_SIGA_INPUT_NEEDED		0x40	/* process input queues */
+#define AC1_SIGA_OUTPUT_NEEDED		0x20	/* process output queues */
+#define AC1_SIGA_SYNC_NEEDED		0x10	/* ask hypervisor to sync */
+#define AC1_AUTOMATIC_SYNC_ON_THININT	0x08	/* set by hypervisor */
+#define AC1_AUTOMATIC_SYNC_ON_OUT_PCI	0x04	/* set by hypervisor */
+#define AC1_SC_QEBSM_AVAILABLE		0x02	/* available for subchannel */
+#define AC1_SC_QEBSM_ENABLED		0x01	/* enabled for subchannel */
+
 #define CHSC_AC2_DATA_DIV_AVAILABLE	0x0010
 #define CHSC_AC2_DATA_DIV_ENABLED	0x0002
 

drivers/s390/cio/qdio.h

@@ -87,15 +87,6 @@ enum qdio_irq_states {
 #define CHSC_FLAG_QDIO_CAPABILITY	0x80
 #define CHSC_FLAG_VALIDITY		0x40
 
-/* qdio adapter-characteristics-1 flag */
-#define AC1_SIGA_INPUT_NEEDED		0x40	/* process input queues */
-#define AC1_SIGA_OUTPUT_NEEDED		0x20	/* process output queues */
-#define AC1_SIGA_SYNC_NEEDED		0x10	/* ask hypervisor to sync */
-#define AC1_AUTOMATIC_SYNC_ON_THININT	0x08	/* set by hypervisor */
-#define AC1_AUTOMATIC_SYNC_ON_OUT_PCI	0x04	/* set by hypervisor */
-#define AC1_SC_QEBSM_AVAILABLE		0x02	/* available for subchannel */
-#define AC1_SC_QEBSM_ENABLED		0x01	/* enabled for subchannel */
-
 /* SIGA flags */
 #define QDIO_SIGA_WRITE		0x00
 #define QDIO_SIGA_READ		0x01

drivers/s390/cio/qdio_main.c

@@ -1592,12 +1592,9 @@ static int handle_inbound(struct qdio_q *q, unsigned int callflags,
 	used = atomic_add_return(count, &q->nr_buf_used) - count;
 	BUG_ON(used + count > QDIO_MAX_BUFFERS_PER_Q);
 
-	/* no need to signal as long as the adapter had free buffers */
-	if (used)
-		return 0;
-
 	if (need_siga_in(q))
 		return qdio_siga_input(q);
+
 	return 0;
 }