From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760114AbYESNSH (ORCPT ); Mon, 19 May 2008 09:18:07 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1759341AbYESNQ6 (ORCPT ); Mon, 19 May 2008 09:16:58 -0400 Received: from earthlight.etchedpixels.co.uk ([81.2.110.250]:57954 "EHLO lxorguk.ukuu.org.uk" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1759242AbYESNQ5 (ORCPT ); Mon, 19 May 2008 09:16:57 -0400 From: Alan Cox Subject: [PATCH 04/57] AR7 watchdog To: akpm@osdl.org, linux-kernel@vger.kernel.org, wim@iguana.be Date: Mon, 19 May 2008 14:05:07 +0100 Message-ID: <20080519130507.31722.61761.stgit@core> In-Reply-To: <20080519124659.31722.51847.stgit@core> References: <20080519124659.31722.51847.stgit@core> User-Agent: StGIT/0.14.1 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Alan Cox Fix locking Use unlocked_ioctl Remove semaphores --- drivers/watchdog/ar7_wdt.c | 29 +++++++++++++++++------------ 1 files changed, 17 insertions(+), 12 deletions(-) diff --git a/drivers/watchdog/ar7_wdt.c b/drivers/watchdog/ar7_wdt.c index 2eb48c0..673f8c0 100644 --- a/drivers/watchdog/ar7_wdt.c +++ b/drivers/watchdog/ar7_wdt.c @@ -69,7 +69,8 @@ struct ar7_wdt { u32 prescale; }; -static struct semaphore open_semaphore; +static unsigned long wdt_is_open; +static spinlock_t wdt_lock; static unsigned expect_close; /* XXX currently fixed, allows max margin ~68.72 secs */ @@ -154,8 +155,10 @@ static void ar7_wdt_update_margin(int new_margin) u32 change; change = new_margin * (ar7_vbus_freq() / prescale_value); - if (change < 1) change = 1; - if (change > 0xffff) change = 0xffff; + if (change < 1) + change = 1; + if (change > 0xffff) + change = 0xffff; ar7_wdt_change(change); margin = change * prescale_value / ar7_vbus_freq(); printk(KERN_INFO DRVNAME @@ -179,7 +182,7 @@ static void ar7_wdt_disable_wdt(void) static int ar7_wdt_open(struct inode *inode, struct file *file) { /* only allow one at a time */ - if (down_trylock(&open_semaphore)) + if (test_and_set_bit(0, &wdt_is_open)) return -EBUSY; ar7_wdt_enable_wdt(); expect_close = 0; @@ -195,9 +198,7 @@ static int ar7_wdt_release(struct inode *inode, struct file *file) "will not disable the watchdog timer\n"); else if (!nowayout) ar7_wdt_disable_wdt(); - - up(&open_semaphore); - + clear_bit(0, &wdt_is_open); return 0; } @@ -222,7 +223,9 @@ static ssize_t ar7_wdt_write(struct file *file, const char *data, if (len) { size_t i; + spin_lock(&wdt_lock); ar7_wdt_kick(1); + spin_unlock(&wdt_lock); expect_close = 0; for (i = 0; i < len; ++i) { @@ -237,8 +240,8 @@ static ssize_t ar7_wdt_write(struct file *file, const char *data, return len; } -static int ar7_wdt_ioctl(struct inode *inode, struct file *file, - unsigned int cmd, unsigned long arg) +static long ar7_wdt_ioctl(struct file *file, + unsigned int cmd, unsigned long arg) { static struct watchdog_info ident = { .identity = LONGNAME, @@ -269,8 +272,10 @@ static int ar7_wdt_ioctl(struct inode *inode, struct file *file, if (new_margin < 1) return -EINVAL; + spin_lock(&wdt_lock); ar7_wdt_update_margin(new_margin); ar7_wdt_kick(1); + spin_unlock(&wdt_lock); case WDIOC_GETTIMEOUT: if (put_user(margin, (int *)arg)) @@ -282,7 +287,7 @@ static int ar7_wdt_ioctl(struct inode *inode, struct file *file, static const struct file_operations ar7_wdt_fops = { .owner = THIS_MODULE, .write = ar7_wdt_write, - .ioctl = ar7_wdt_ioctl, + .unlocked_ioctl = ar7_wdt_ioctl, .open = ar7_wdt_open, .release = ar7_wdt_release, }; @@ -297,6 +302,8 @@ static int __init ar7_wdt_init(void) { int rc; + spin_lock_init(&wdt_lock); + ar7_wdt_get_regs(); if (!request_mem_region(ar7_regs_wdt, sizeof(struct ar7_wdt), @@ -312,8 +319,6 @@ static int __init ar7_wdt_init(void) ar7_wdt_prescale(prescale_value); ar7_wdt_update_margin(margin); - sema_init(&open_semaphore, 1); - rc = register_reboot_notifier(&ar7_wdt_notifier); if (rc) { printk(KERN_ERR DRVNAME