From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933807AbZHEJB6 (ORCPT ); Wed, 5 Aug 2009 05:01:58 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932781AbZHEJB6 (ORCPT ); Wed, 5 Aug 2009 05:01:58 -0400 Received: from cantor.suse.de ([195.135.220.2]:56141 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932688AbZHEJB5 (ORCPT ); Wed, 5 Aug 2009 05:01:57 -0400 Message-ID: <4A794A7F.4090907@suse.de> Date: Wed, 05 Aug 2009 18:01:51 +0900 From: Tejun Heo User-Agent: Thunderbird 2.0.0.22 (X11/20090605) MIME-Version: 1.0 To: Takashi Iwai Cc: Greg KH , Al Viro , Linux Kernel , cguthrie@mandriva.org Subject: [PATCH 1/2 UPDATED] chrdev: implement __[un]register_chrdev() References: <4A79283E.7030202@kernel.org> <4A793099.1040704@kernel.org> <4A79350A.3020904@kernel.org> In-Reply-To: <4A79350A.3020904@kernel.org> X-Enigmail-Version: 0.95.7 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org [un]register_chrdev() assume minor range 0-255. This patch adds __ prefixed versions which take @minorbase and @count explicitly. The original ones become inline wrappers around __ ones. Signed-off-by: Tejun Heo Cc: Al Viro Cc: Greg Kroah-Hartman --- fs/char_dev.c | 39 ++++++++++++++++++++++++++------------- include/linux/fs.h | 19 ++++++++++++++++--- 2 files changed, 42 insertions(+), 16 deletions(-) Index: work/fs/char_dev.c =================================================================== --- work.orig/fs/char_dev.c +++ work/fs/char_dev.c @@ -237,8 +237,10 @@ int alloc_chrdev_region(dev_t *dev, unsi } /** - * register_chrdev() - Register a major number for character devices. + * __register_chrdev() - create and register a cdev occupying a range of minors * @major: major device number or 0 for dynamic allocation + * @baseminor: first of the requested range of minor numbers + * @count: the number of minor numbers required * @name: name of this range of devices * @fops: file operations associated with this devices * @@ -254,19 +256,17 @@ int alloc_chrdev_region(dev_t *dev, unsi * /dev. It only helps to keep track of the different owners of devices. If * your module name has only one type of devices it's ok to use e.g. the name * of the module here. - * - * This function registers a range of 256 minor numbers. The first minor number - * is 0. */ -int register_chrdev(unsigned int major, const char *name, - const struct file_operations *fops) +int __register_chrdev(unsigned int major, unsigned int baseminor, + unsigned int count, const char *name, + const struct file_operations *fops) { struct char_device_struct *cd; struct cdev *cdev; char *s; int err = -ENOMEM; - cd = __register_chrdev_region(major, 0, 256, name); + cd = __register_chrdev_region(major, baseminor, count, name); if (IS_ERR(cd)) return PTR_ERR(cd); @@ -280,7 +280,7 @@ int register_chrdev(unsigned int major, for (s = strchr(kobject_name(&cdev->kobj),'/'); s; s = strchr(s, '/')) *s = '!'; - err = cdev_add(cdev, MKDEV(cd->major, 0), 256); + err = cdev_add(cdev, MKDEV(cd->major, baseminor), count); if (err) goto out; @@ -290,7 +290,7 @@ int register_chrdev(unsigned int major, out: kobject_put(&cdev->kobj); out2: - kfree(__unregister_chrdev_region(cd->major, 0, 256)); + kfree(__unregister_chrdev_region(cd->major, baseminor, count)); return err; } @@ -316,10 +316,23 @@ void unregister_chrdev_region(dev_t from } } -void unregister_chrdev(unsigned int major, const char *name) +/** + * __unregister_chrdev - unregister and destroy a cdev + * @major: major device number + * @baseminor: first of the range of minor numbers + * @count: the number of minor numbers this cdev is occupying + * @name: name of this range of devices + * + * Unregister and destroy the cdev occupying the region described by + * @major, @baseminor and @count. This function undoes what + * __register_chrdev() did. + */ +void __unregister_chrdev(unsigned int major, unsigned int baseminor, + unsigned int count, const char *name) { struct char_device_struct *cd; - cd = __unregister_chrdev_region(major, 0, 256); + + cd = __unregister_chrdev_region(major, baseminor, count); if (cd && cd->cdev) cdev_del(cd->cdev); kfree(cd); @@ -568,6 +581,6 @@ EXPORT_SYMBOL(cdev_alloc); EXPORT_SYMBOL(cdev_del); EXPORT_SYMBOL(cdev_add); EXPORT_SYMBOL(cdev_index); -EXPORT_SYMBOL(register_chrdev); -EXPORT_SYMBOL(unregister_chrdev); +EXPORT_SYMBOL(__register_chrdev); +EXPORT_SYMBOL(__unregister_chrdev); EXPORT_SYMBOL(directly_mappable_cdev_bdi); Index: work/include/linux/fs.h =================================================================== --- work.orig/include/linux/fs.h +++ work/include/linux/fs.h @@ -1998,12 +1998,25 @@ extern void bd_release_from_disk(struct #define CHRDEV_MAJOR_HASH_SIZE 255 extern int alloc_chrdev_region(dev_t *, unsigned, unsigned, const char *); extern int register_chrdev_region(dev_t, unsigned, const char *); -extern int register_chrdev(unsigned int, const char *, - const struct file_operations *); -extern void unregister_chrdev(unsigned int, const char *); +extern int __register_chrdev(unsigned int major, unsigned int baseminor, + unsigned int count, const char *name, + const struct file_operations *fops); +extern void __unregister_chrdev(unsigned int major, unsigned int baseminor, + unsigned int count, const char *name); extern void unregister_chrdev_region(dev_t, unsigned); extern void chrdev_show(struct seq_file *,off_t); +static inline int register_chrdev(unsigned int major, const char *name, + const struct file_operations *fops) +{ + return __register_chrdev(major, 0, 256, name, fops); +} + +static inline void unregister_chrdev(unsigned int major, const char *name) +{ + __unregister_chrdev(major, 0, 256, name); +} + /* fs/block_dev.c */ #define BDEVNAME_SIZE 32 /* Largest string for a blockdev identifier */ #define BDEVT_SIZE 10 /* Largest string for MAJ:MIN for blkdev */