From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933871AbXGKXn3 (ORCPT ); Wed, 11 Jul 2007 19:43:29 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S935119AbXGKXec (ORCPT ); Wed, 11 Jul 2007 19:34:32 -0400 Received: from ns1.suse.de ([195.135.220.2]:33818 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934994AbXGKXea (ORCPT ); Wed, 11 Jul 2007 19:34:30 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Tejun Heo , Greg Kroah-Hartman Subject: [PATCH 23/61] sysfs: allocate inode number using ida Date: Wed, 11 Jul 2007 16:31:42 -0700 Message-Id: <11841968471598-git-send-email-gregkh@suse.de> X-Mailer: git-send-email 1.5.2.2 In-Reply-To: <11841968431153-git-send-email-gregkh@suse.de> References: <20070711233021.GA5253@kroah.com> <11841967403365-git-send-email-gregkh@suse.de> <11841967493890-git-send-email-gregkh@suse.de> <1184196753488-git-send-email-gregkh@suse.de> <1184196759393-git-send-email-gregkh@suse.de> <11841967633087-git-send-email-gregkh@suse.de> <11841967674155-git-send-email-gregkh@suse.de> <11841967711788-git-send-email-gregkh@suse.de> <11841967793134-git-send-email-gregkh@suse.de> <1184196783245-git-send-email-gregkh@suse.de> <1184196787247-git-send-email-gregkh@suse.de> <11841967992975-git-send-email-gregkh@suse.de> <11841968032469-git-send-email-gregkh@suse.de> <11841968071826-git-send-email-gregkh@suse.de> <11841968111201-git-send-email-gregkh@suse.de> <11841968151257-git-send-email-gregkh@suse.de> <1184196818497-git-send-email-gregkh@suse.de> <11841968231043-git-send-email-gregkh@suse.de> <11841968271925-git-send-email-gregkh@suse.de> <11841968303508-git-send-email-gregkh@suse.de> <11841968352439-git-send-email-gregkh@suse.de> <11841968392043-git-send-email-gregkh@suse.de> <11841968431153-git-send-email-gregkh@suse.de> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org From: Tejun Heo sysfs used simple incrementing allocator which is not guaranteed to be unique. This patch makes sysfs use ida to give each sd a unique and packed inode number. Signed-off-by: Tejun Heo Signed-off-by: Greg Kroah-Hartman --- fs/sysfs/dir.c | 45 ++++++++++++++++++++++++++++++++++++--------- 1 files changed, 36 insertions(+), 9 deletions(-) diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c index 2544aae..f09626c 100644 --- a/fs/sysfs/dir.c +++ b/fs/sysfs/dir.c @@ -9,12 +9,42 @@ #include #include #include +#include #include #include "sysfs.h" DECLARE_RWSEM(sysfs_rename_sem); spinlock_t sysfs_lock = SPIN_LOCK_UNLOCKED; +static spinlock_t sysfs_ino_lock = SPIN_LOCK_UNLOCKED; +static DEFINE_IDA(sysfs_ino_ida); + +int sysfs_alloc_ino(ino_t *pino) +{ + int ino, rc; + + retry: + spin_lock(&sysfs_ino_lock); + rc = ida_get_new_above(&sysfs_ino_ida, 2, &ino); + spin_unlock(&sysfs_ino_lock); + + if (rc == -EAGAIN) { + if (ida_pre_get(&sysfs_ino_ida, GFP_KERNEL)) + goto retry; + rc = -ENOMEM; + } + + *pino = ino; + return rc; +} + +static void sysfs_free_ino(ino_t ino) +{ + spin_lock(&sysfs_ino_lock); + ida_remove(&sysfs_ino_ida, ino); + spin_unlock(&sysfs_ino_lock); +} + void release_sysfs_dirent(struct sysfs_dirent * sd) { if (sd->s_type & SYSFS_KOBJ_LINK) { @@ -24,6 +54,7 @@ void release_sysfs_dirent(struct sysfs_dirent * sd) kfree(sl); } kfree(sd->s_iattr); + sysfs_free_ino(sd->s_ino); kmem_cache_free(sysfs_dir_cachep, sd); } @@ -54,14 +85,6 @@ static struct dentry_operations sysfs_dentry_ops = { .d_iput = sysfs_d_iput, }; -static unsigned int sysfs_inode_counter; -ino_t sysfs_get_inum(void) -{ - if (unlikely(sysfs_inode_counter < 3)) - sysfs_inode_counter = 3; - return sysfs_inode_counter++; -} - /* * Allocates a new sysfs_dirent and links it to the parent sysfs_dirent */ @@ -73,7 +96,11 @@ static struct sysfs_dirent * __sysfs_new_dirent(void * element) if (!sd) return NULL; - sd->s_ino = sysfs_get_inum(); + if (sysfs_alloc_ino(&sd->s_ino)) { + kmem_cache_free(sysfs_dir_cachep, sd); + return NULL; + } + atomic_set(&sd->s_count, 1); atomic_set(&sd->s_event, 1); INIT_LIST_HEAD(&sd->s_children); -- 1.5.2.2