Dear Kernel Developers,

I have seen that drivers/char/misc.c already used the deprecated 
register_chrdev call and this limited the number of minors to 256.

I recetly asked for a misc minor number attribution for View-OS/kmview
and Torben Mathiasen told me about this issue.

I propose this patch that eliminate both problems. With this patch 
misc allocates the entire major 10 and avoids the deprecated call.

These are just my 2 (euro) cents, I hope it can be useful.

        renzo
-- 
============================================================================
Renzo Davoli                            | Dept. of Computer Science
(NIC rd235, HAM IZ4DJE)                 | University of Bologna 
Tel. +39 051 2094501                    | Mura Anteo Zamboni, 7
Fax. +39 051 2094510                    | I-40127 Bologna  ITALY
Key fingerprint = A019 17E2 5562 06F6 77BB  2E93 1A01 F646 30EA B487
============================================================================
--- drivers/char/misc.orig.c    2007-08-05 16:56:59.000000000 +0200
+++ drivers/char/misc.c 2007-09-06 11:07:51.000000000 +0200
@@ -56,6 +56,8 @@
 static LIST_HEAD(misc_list);
 static DEFINE_MUTEX(misc_mtx);
 
+static struct cdev misc_cdev;
+
 /*
  * Assigned numbers, used for dynamic minors
  */
@@ -273,6 +275,31 @@
 EXPORT_SYMBOL(misc_register);
 EXPORT_SYMBOL(misc_deregister);
 
+static int misc_register_chrdev(void)
+{
+       dev_t from=MKDEV(MISC_MAJOR,0);
+       int rv;
+       int err = -ENOMEM;
+       char *s;
+
+       if ((rv=register_chrdev_region(from,MINORMASK,"misc")) != 0)
+               return rv;
+
+       cdev_init(&misc_cdev, &misc_fops);
+       misc_cdev.owner=misc_fops.owner;
+       kobject_set_name(&misc_cdev.kobj, "%s", "misc");
+       for (s = strchr(kobject_name(&misc_cdev.kobj),'/'); s; s = strchr(s, 
'/'))
+                   *s = '!';
+       err = cdev_add(&misc_cdev, from, MINORMASK);
+       if (err)
+               goto out;
+       return 0;
+out:
+       kobject_put(&misc_cdev.kobj);
+       unregister_chrdev_region(from,MINORMASK);
+  return err;
+}
+
 static int __init misc_init(void)
 {
 #ifdef CONFIG_PROC_FS
@@ -286,7 +313,7 @@
        if (IS_ERR(misc_class))
                return PTR_ERR(misc_class);
 
-       if (register_chrdev(MISC_MAJOR,"misc",&misc_fops)) {
+       if (misc_register_chrdev()) {
                printk("unable to get major %d for misc devices\n",
                       MISC_MAJOR);
                class_destroy(misc_class);

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