[PATCH] s390: common i/o layer

From: Cornelia Huck <cohuck@de.ibm.com>
From: Steffen Thoss <thoss@de.ibm.com>

common i/o layer changes:
 - Delay re-registration of a subchannel with a different subchannel id
   until the ccw device removal triggered from the subchannels remove
   function has completed.
 - Fix check when to call unreg_rereg.
 - Fix get_disc_cdev_by_devno.
 - Activate the time delay disablement facility. This saves a few cycles
   in millicode processing.
 - Don't ifdef reset of busy start time.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

drivers/s390/cio/device.c

 /*
  *  drivers/s390/cio/device.c
  *  bus driver for ccw devices
- *   $Revision: 1.128 $
+ *   $Revision: 1.129 $
  *
  *    Copyright (C) 2002 IBM Deutschland Entwicklung GmbH,
  *			 IBM Corporation
@@ -525,8 +525,7 @@ get_disc_ccwdev_by_devno(unsigned int devno, struct ccw_device *sibling)
 		cdev = to_ccwdev(dev);
 		if ((cdev->private->state == DEV_STATE_DISCONNECTED) &&
 		    (cdev->private->devno == devno) &&
-		    (!strncmp(cdev->dev.bus_id, sibling->dev.bus_id,
-			      BUS_ID_SIZE))) {
+		    (cdev != sibling)) {
 			cdev->private->state = DEV_STATE_NOT_OPER;
 			break;
 		}
@@ -539,6 +538,24 @@ get_disc_ccwdev_by_devno(unsigned int devno, struct ccw_device *sibling)
 	return cdev;
 }
 
+static void
+ccw_device_add_changed(void *data)
+{
+
+	struct ccw_device *cdev;
+
+	cdev = (struct ccw_device *)data;
+	if (device_add(&cdev->dev)) {
+		put_device(&cdev->dev);
+		return;
+	}
+	set_bit(1, &cdev->private->registered);
+	if (device_add_files(&cdev->dev)) {
+		if (test_and_clear_bit(1, &cdev->private->registered))
+			device_unregister(&cdev->dev);
+	}
+}
+
 extern int css_get_ssd_info(struct subchannel *sch);
 
 void
@@ -593,15 +610,9 @@ ccw_device_do_unreg_rereg(void *data)
 	if (need_rename)
 		snprintf (cdev->dev.bus_id, BUS_ID_SIZE, "0.0.%04x",
 			  sch->schib.pmcw.dev);
-	if (device_add(&cdev->dev)) {
-		put_device(&cdev->dev);
-		return;
-	}
-	set_bit(1, &cdev->private->registered);
-	if (device_add_files(&cdev->dev)) {
-		if (test_and_clear_bit(1, &cdev->private->registered))
-			device_unregister(&cdev->dev);
-	}
+	PREPARE_WORK(&cdev->private->kick_work,
+		     ccw_device_add_changed, (void *)cdev);
+	queue_work(ccw_device_work, &cdev->private->kick_work);
 }
 
 static void

drivers/s390/cio/device_fsm.c

@@ -154,7 +154,7 @@ ccw_device_cancel_halt_clear(struct ccw_device *cdev)
 	panic("Can't stop i/o on subchannel.\n");
 }
 
-static void
+static int
 ccw_device_handle_oper(struct ccw_device *cdev)
 {
 	struct subchannel *sch;
@@ -174,9 +174,10 @@ ccw_device_handle_oper(struct ccw_device *cdev)
 		PREPARE_WORK(&cdev->private->kick_work,
 			     ccw_device_do_unreg_rereg, (void *)cdev);
 		queue_work(ccw_device_work, &cdev->private->kick_work);
-		return;
+		return 0;
 	}
 	cdev->private->flags.donotify = 1;
+	return 1;
 }
 
 /*
@@ -206,7 +207,7 @@ static void
 ccw_device_recog_done(struct ccw_device *cdev, int state)
 {
 	struct subchannel *sch;
-	int notify, old_lpm;
+	int notify, old_lpm, same_dev;
 
 	sch = to_subchannel(cdev->dev.parent);
 
@@ -236,6 +237,7 @@ ccw_device_recog_done(struct ccw_device *cdev, int state)
 		/* Boxed devices don't need extra treatment. */
 	}
 	notify = 0;
+	same_dev = 0; /* Keep the compiler quiet... */
 	switch (state) {
 	case DEV_STATE_NOT_OPER:
 		CIO_DEBUG(KERN_WARNING, 2,
@@ -244,7 +246,7 @@ ccw_device_recog_done(struct ccw_device *cdev, int state)
 		break;
 	case DEV_STATE_OFFLINE:
 		if (cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID) {
-			ccw_device_handle_oper(cdev);
+			same_dev = ccw_device_handle_oper(cdev);
 			notify = 1;
 		}
 		/* fill out sense information */
@@ -255,10 +257,12 @@ ccw_device_recog_done(struct ccw_device *cdev, int state)
 			.dev_model = cdev->private->senseid.dev_model,
 		};
 		if (notify) {
-			/* Get device online again. */
 			cdev->private->state = DEV_STATE_OFFLINE;
+			if (same_dev) {
+				/* Get device online again. */
 				ccw_device_online(cdev);
 				wake_up(&cdev->private->wait_q);
+			}
 			return;
 		}
 		/* Issue device info message. */

drivers/s390/cio/qdio.c

@@ -56,7 +56,7 @@
 #include "ioasm.h"
 #include "chsc.h"
 
-#define VERSION_QDIO_C "$Revision: 1.89 $"
+#define VERSION_QDIO_C "$Revision: 1.93 $"
 
 /****************** MODULE PARAMETER VARIABLES ********************/
 MODULE_AUTHOR("Utz Bacher <utz.bacher@de.ibm.com>");
@@ -605,8 +605,8 @@ qdio_kick_outbound_q(struct qdio_q *q)
 			sprintf(dbf_text,"%4x%2x%2x",q->irq,q->q_no,
 				atomic_read(&q->busy_siga_counter));
 			QDIO_DBF_TEXT3(0,trace,dbf_text);
-			q->timing.busy_start=0;
 #endif /* CONFIG_QDIO_DEBUG */
+			q->timing.busy_start=0;
 			break;
 		case (2|QDIO_SIGA_ERROR_B_BIT_SET):
 			/* cc=2 and busy bit: */
@@ -2088,7 +2088,10 @@ tiqdio_set_subchannel_ind(struct qdio_irq *irq_ptr, int reset_to_zero)
 		u32 kc:4;
 		u32 reserved4:21;
 		u32 isc:3;
-		u32 reserved5[2];
+		u32 word_with_d_bit;
+		/* set to 0x10000000 to enable
+		 * time delay disablement facility */
+		u32 reserved5;
 		u32 subsystem_id;
 		u32 reserved6[1004];
 		struct chsc_header response;
@@ -2126,6 +2129,12 @@ tiqdio_set_subchannel_ind(struct qdio_irq *irq_ptr, int reset_to_zero)
 	scssc_area->kc = QDIO_STORAGE_KEY;
 	scssc_area->isc = TIQDIO_THININT_ISC;
 	scssc_area->subsystem_id = (1<<16) + irq_ptr->irq;
+	/* enables the time delay disablement facility. Don't care
+	 * whether it is really there (i.e. we haven't checked for
+	 * it) */
+	scssc_area->word_with_d_bit = 0x10000000;
+
+
 
 	result = chsc(scssc_area);
 	if (result) {
@@ -2620,6 +2629,7 @@ qdio_allocate(struct qdio_initialize *init_data)
 
 	init_MUTEX(&irq_ptr->setting_up_sema);
 
+	/* QDR must be in DMA area since CCW data address is only 32 bit */
 	irq_ptr->qdr=kmalloc(sizeof(struct qdr), GFP_KERNEL | GFP_DMA);
   	if (!(irq_ptr->qdr)) {
    		kfree(irq_ptr);