From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757216AbXIFKEl (ORCPT ); Thu, 6 Sep 2007 06:04:41 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755073AbXIFKEe (ORCPT ); Thu, 6 Sep 2007 06:04:34 -0400 Received: from leb.cs.unibo.it ([130.136.1.102]:52240 "EHLO leb.cs.unibo.it" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755561AbXIFKEd (ORCPT ); Thu, 6 Sep 2007 06:04:33 -0400 X-Greylist: delayed 1542 seconds by postgrey-1.27 at vger.kernel.org; Thu, 06 Sep 2007 06:04:32 EDT Date: Thu, 6 Sep 2007 12:04:31 +0200 To: linux-kernel@vger.kernel.org Cc: "Mathiasen, Torben" Subject: Re: [PATCH] drivers/char/misc.c: deprecated call register_chrdev, and 256 minor limit eliminated Message-ID: <20070906100431.GD8222@cs.unibo.it> References: <20070906093844.GC8222@cs.unibo.it> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20070906093844.GC8222@cs.unibo.it> User-Agent: Mutt/1.5.11 From: renzo@cs.unibo.it (Renzo Davoli) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Sep 06, 2007 at 11:38:44AM +0200, Renzo Davoli wrote: 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 Signed-off-by: Renzo Davoli -- ============================================================================ 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); -- ============================================================================ 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 ============================================================================