[PATCH] s390 (3/7): dasd driver.

 - Remove dynamic allocation of major numbers. Just use static major 94.
 - Use bus_id instead of device number where possible.
 - Don't check open_count in dasd_generic_set_offline.

drivers/s390/block/dasd.c

@@ -7,7 +7,7 @@
  * Bugreports.to..: <Linux390@de.ibm.com>
  * (C) IBM Corporation, IBM Deutschland Entwicklung GmbH, 1999-2001
  *
- * $Revision: 1.110 $
+ * $Revision: 1.114 $
  */
 
 #include <linux/config.h>
@@ -1142,8 +1142,8 @@ __dasd_process_blk_queue(struct dasd_device * device)
 		req = elv_next_request(queue);
 		if (device->ro_flag && rq_data_dir(req) == WRITE) {
 			DBF_EVENT(DBF_ERR,
-				  "(%04x) Rejecting write request %p",
-				  _ccw_device_get_device_number(device->cdev),
+				  "(%s) Rejecting write request %p",
+				  device->cdev->dev.bus_id,
 				  req);
 			blkdev_dequeue_request(req);
 			dasd_end_request(req, 0);
@@ -1154,8 +1154,8 @@ __dasd_process_blk_queue(struct dasd_device * device)
 			if (PTR_ERR(cqr) == -ENOMEM)
 				break;	/* terminate request queue loop */
 			DBF_EVENT(DBF_ERR,
-				  "(%04x) CCW creation failed on request %p",
-				  _ccw_device_get_device_number(device->cdev),
+				  "(%s) CCW creation failed on request %p",
+				  device->cdev->dev.bus_id,
 				  req);
 			blkdev_dequeue_request(req);
 			dasd_end_request(req, 0);
@@ -1728,12 +1728,10 @@ int
 dasd_generic_probe (struct ccw_device *cdev,
 		    struct dasd_discipline *discipline)
 {
-	int devno;
 	int ret = 0;
 
-	devno = _ccw_device_get_device_number(cdev);
-	if (dasd_autodetect
-	    && (ret = dasd_add_range(devno, devno, DASD_FEATURE_DEFAULT))) {
+	if (dasd_autodetect &&
+	    (ret = dasd_add_busid(cdev->dev.bus_id, DASD_FEATURE_DEFAULT))) {
 		printk (KERN_WARNING
 			"dasd_generic_probe: cannot autodetect %s\n",
 			cdev->dev.bus_id);
@@ -1830,12 +1828,6 @@ dasd_generic_set_offline (struct ccw_device *cdev)
 	struct dasd_device *device;
 
 	device = cdev->dev.driver_data;
-	if (atomic_read(&device->open_count) > 0) {
-		printk (KERN_WARNING "Can't offline dasd device with open"
-			" count = %i.\n",
-			atomic_read(&device->open_count));
-		return -EBUSY;
-	}
 	dasd_set_target_state(device, DASD_STATE_NEW);
 	dasd_delete_device(device);
 	
@@ -1854,7 +1846,6 @@ dasd_generic_auto_online (struct ccw_driver *dasd_discipline_driver)
 	struct device_driver *drv;
 	struct device *d, *dev;
 	struct ccw_device *cdev;
-	int devno;
 
 	drv = get_driver(&dasd_discipline_driver->driver);
 	down_read(&drv->bus->subsys.rwsem);
@@ -1864,8 +1855,7 @@ dasd_generic_auto_online (struct ccw_driver *dasd_discipline_driver)
 		if (!dev)
 			continue;
 		cdev = to_ccwdev(dev);
-		devno = _ccw_device_get_device_number(cdev);
-		if (dasd_autodetect || dasd_devno_in_range(devno) == 0)
+		if (dasd_autodetect || dasd_busid_known(cdev->dev.bus_id) == 0)
 			ccw_device_set_online(cdev);
 		put_device(dev);
 	}
@@ -1934,31 +1924,6 @@ dasd_use_diag_store(struct device *dev, const char *buf, size_t count)
 static
 DEVICE_ATTR(use_diag, 0644, dasd_use_diag_show, dasd_use_diag_store);
 
-#if 0
-/* this file shows the same information as /proc/dasd/devices using
- * an inaccaptable interface */
-/* TODO: Split this up into smaller files! */
-static ssize_t
-dasd_devices_show(struct device *dev, char *buf)
-{
-	
-	struct dasd_device *device;
-	dasd_devmap_t *devmap;
-
-	devmap = NULL;
-	device = dev->driver_data;
-	if (device)
-		devmap = dasd_devmap_from_devno(device->devno);
-
-	if (!devmap)
-		return sprintf(buf, "unused\n");
-
-	return min ((size_t) dasd_devices_print(devmap, buf), PAGE_SIZE);
-}
-
-static DEVICE_ATTR(dasd, 0444, dasd_devices_show, 0);
-#endif
-
 static ssize_t
 dasd_discipline_show(struct device *dev, char *buf)
 {
@@ -1973,7 +1938,6 @@ dasd_discipline_show(struct device *dev, char *buf)
 static DEVICE_ATTR(discipline, 0444, dasd_discipline_show, NULL);
 
 static struct attribute * dasd_attrs[] = {
-	//&dev_attr_dasd.attr,
 	&dev_attr_readonly.attr,
 	&dev_attr_discipline.attr,
 	&dev_attr_use_diag.attr,

drivers/s390/block/dasd_genhd.c

@@ -7,9 +7,9 @@
  * Bugreports.to..: <Linux390@de.ibm.com>
  * (C) IBM Corporation, IBM Deutschland Entwicklung GmbH, 1999-2001
  *
- * Dealing with devices registered to multiple major numbers.
+ * gendisk related functions for the dasd driver.
  *
- * $Revision: 1.38 $
+ * $Revision: 1.41 $
  */
 
 #include <linux/config.h>
@@ -24,116 +24,26 @@
 
 #include "dasd_int.h"
 
-static spinlock_t dasd_major_lock = SPIN_LOCK_UNLOCKED;
-static struct list_head dasd_major_info = LIST_HEAD_INIT(dasd_major_info);
-
-struct major_info {
-	struct list_head list;
-	int major;
-};
-
-/*
- * Register major number for the dasd driver. Call with DASD_MAJOR to
- * setup the static dasd device major 94 or with 0 to allocated a major
- * dynamically.
- */
-static int
-dasd_register_major(int major)
-{
-	struct major_info *mi;
-	int new_major;
-
-	/* Allocate major info structure. */
-	mi = kmalloc(sizeof(struct major_info), GFP_KERNEL);
-
-	/* Check if one of the allocations failed. */
-	if (mi == NULL) {
-		MESSAGE(KERN_WARNING, "%s",
-			"Cannot get memory to allocate another "
-			"major number");
-		return -ENOMEM;
-	}
-
-	/* Register block device. */
-	new_major = register_blkdev(major, "dasd");
-	if (new_major < 0) {
-		kfree(mi);
-		return new_major;
-	}
-	if (major != 0)
-		new_major = major;
-
-	/* Initialize major info structure. */
-	mi->major = new_major;
-
-	/* Insert the new major info structure into dasd_major_info list. */
-	spin_lock(&dasd_major_lock);
-	list_add_tail(&mi->list, &dasd_major_info);
-	spin_unlock(&dasd_major_lock);
-
-	return 0;
-}
-
-static void
-dasd_unregister_major(struct major_info * mi)
-{
-	int rc;
-
-	if (mi == NULL)
-		return;
-
-	/* Delete the major info from dasd_major_info. */
-	spin_lock(&dasd_major_lock);
-	list_del(&mi->list);
-	spin_unlock(&dasd_major_lock);
-
-	rc = unregister_blkdev(mi->major, "dasd");
-	if (rc < 0)
-		MESSAGE(KERN_WARNING,
-			"Cannot unregister from major no %d, rc = %d",
-			mi->major, rc);
-
-	/* Free memory. */
-	kfree(mi);
-}
-
 /*
  * Allocate and register gendisk structure for device.
  */
 int
 dasd_gendisk_alloc(struct dasd_device *device)
 {
-	struct major_info *mi;
 	struct gendisk *gdp;
-	int index, len, rc;
-
-	/* Make sure the major for this device exists. */
-	mi = NULL;
-	while (1) {
-		spin_lock(&dasd_major_lock);
-		index = device->devindex;
-		list_for_each_entry(mi, &dasd_major_info, list) {
-			if (index < DASD_PER_MAJOR)
-				break;
-			index -= DASD_PER_MAJOR;
-		}
-		spin_unlock(&dasd_major_lock);
-		if (index < DASD_PER_MAJOR)
-			break;
-		rc = dasd_register_major(0);
-		if (rc) {
-			DBF_EXC(DBF_ALERT, "%s", "out of major numbers!");
-			return rc;
-		}
-	}
-	
+	int len;
+
+	/* Make sure the minor for this device exists. */
+	if (device->devindex >= DASD_PER_MAJOR)
+		return -EBUSY;
+
 	gdp = alloc_disk(1 << DASD_PARTN_BITS);
 	if (!gdp)
 		return -ENOMEM;
 
 	/* Initialize gendisk structure. */
-	gdp->major = mi->major;
-	gdp->first_minor = index << DASD_PARTN_BITS;
+	gdp->major = DASD_MAJOR;
+	gdp->first_minor = device->devindex << DASD_PARTN_BITS;
 	gdp->fops = &dasd_device_operations;
 	gdp->driverfs_dev = &device->cdev->dev;
 
@@ -153,8 +63,7 @@ dasd_gendisk_alloc(struct dasd_device *device)
 	}
 	len += sprintf(gdp->disk_name + len, "%c", 'a'+(device->devindex%26));
 
- 	sprintf(gdp->devfs_name, "dasd/%04x",
-		_ccw_device_get_device_number(device->cdev));
+ 	sprintf(gdp->devfs_name, "dasd/%s", device->cdev->dev.bus_id);
 
 	if (device->ro_flag)
 		set_disk_ro(gdp, 1);
@@ -173,6 +82,7 @@ void
 dasd_gendisk_free(struct dasd_device *device)
 {
 	del_gendisk(device->gdp);
+	device->gdp->queue = 0;
 	put_disk(device->gdp);
 	device->gdp = 0;
 }
@@ -221,7 +131,7 @@ dasd_gendisk_init(void)
 	int rc;
 
 	/* Register to static dasd major 94 */
-	rc = dasd_register_major(DASD_MAJOR);
+	rc = register_blkdev(DASD_MAJOR, "dasd");
 	if (rc != 0) {
 		MESSAGE(KERN_WARNING,
 			"Couldn't register successfully to "
@@ -234,10 +144,5 @@ dasd_gendisk_init(void)
 void
 dasd_gendisk_exit(void)
 {
-	struct list_head *l, *n;
-
-	spin_lock(&dasd_major_lock);
-	list_for_each_safe(l, n, &dasd_major_info)
-		dasd_unregister_major(list_entry(l, struct major_info, list));
-	spin_unlock(&dasd_major_lock);
+	unregister_blkdev(DASD_MAJOR, "dasd");
 }

drivers/s390/block/dasd_int.h

@@ -6,7 +6,7 @@
  * Bugreports.to..: <Linux390@de.ibm.com>
  * (C) IBM Corporation, IBM Deutschland Entwicklung GmbH, 1999,2000
  *
- * $Revision: 1.45 $
+ * $Revision: 1.48 $
  */
 
 #ifndef DASD_INT_H
@@ -15,7 +15,7 @@
 #ifdef __KERNEL__
 
 /* we keep old device allocation scheme; IOW, minors are still in 0..255 */
-#define DASD_PER_MAJOR ( 1U<<(8-DASD_PARTN_BITS))
+#define DASD_PER_MAJOR (1U << (MINORBITS - DASD_PARTN_BITS))
 #define DASD_PARTN_MASK ((1 << DASD_PARTN_BITS) - 1)
 
 /*
@@ -477,8 +477,8 @@ void dasd_delete_device(struct dasd_device *);
 struct dasd_device *dasd_device_from_devindex(int);
 
 int dasd_parse(void);
-int dasd_add_range(int, int, int);
-int dasd_devno_in_range(int);
+int dasd_add_busid(char *, int);
+int dasd_busid_known(char *);
 
 /* externals in dasd_gendisk.c */
 int  dasd_gendisk_init(void);

drivers/s390/block/dasd_proc.c

@@ -9,7 +9,7 @@
  *
  * /proc interface for the dasd driver.
  *
- * $Revision: 1.22 $
+ * $Revision: 1.23 $
  */
 
 #include <linux/config.h>
@@ -59,7 +59,7 @@ dasd_devices_show(struct seq_file *m, void *v)
 	if (IS_ERR(device))
 		return 0;
 	/* Print device number. */
-	seq_printf(m, "%04x", _ccw_device_get_device_number(device->cdev));
+	seq_printf(m, "%s", device->cdev->dev.bus_id);
 	/* Print discipline string. */
 	if (device != NULL && device->discipline != NULL)
 		seq_printf(m, "(%s)", device->discipline->name);