[PATCH] s390: dasd set online failure

dasd driver changes:
 - The feature check in dasd_generic_online returns an error if
   the devmap entry for the device is not yet available. Check
   for the feature after the device has been created.
 - Do symmetric registration/deregistration of cdev->handler.

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>

1 files changed, 9 insertions, 7 deletions

diff --git a/drivers/s390/block/dasd.c b/drivers/s390/block/dasd.c
index 02cfe244e069..ceeb3cf64a16 100644
--- a/drivers/s390/block/dasd.c
+++ b/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: 1.161 $
+ * $Revision: 1.164 $
  */
 
 #include <linux/config.h>
@@ -1766,10 +1766,10 @@ dasd_generic_probe (struct ccw_device *cdev,
                 printk(KERN_WARNING
                        "dasd_generic_probe: could not add sysfs entries "
                        "for %s\n", cdev->dev.bus_id);
+        } else {
+                cdev->handler = &dasd_int_handler;
         }
 
-        cdev->handler = &dasd_int_handler;
-
         return ret;
 }
 
@@ -1780,6 +1780,8 @@ dasd_generic_remove (struct ccw_device *cdev)
 {
         struct dasd_device *device;
 
+        cdev->handler = NULL;
+
         dasd_remove_sysfs_files(cdev);
         device = dasd_device_from_cdev(cdev);
         if (IS_ERR(device))
@@ -1810,14 +1812,14 @@ dasd_generic_set_online (struct ccw_device *cdev,
         struct dasd_device *device;
         int feature_diag, rc;
 
-        feature_diag = dasd_get_feature(cdev, DASD_FEATURE_USEDIAG);
-        if (feature_diag < 0)
-                return feature_diag;
-
         device = dasd_create_device(cdev);
         if (IS_ERR(device))
                 return PTR_ERR(device);
 
+        feature_diag = dasd_get_feature(cdev, DASD_FEATURE_USEDIAG);
+        if (feature_diag < 0)
+                return feature_diag;
+
         if (feature_diag) {
                 if (!dasd_diag_discipline_pointer) {
                         printk (KERN_WARNING