Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755983Ab0GCVsB (ORCPT ); Sat, 3 Jul 2010 17:48:01 -0400 Received: from moutng.kundenserver.de ([212.227.126.187]:52889 "EHLO moutng.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752443Ab0GCVre (ORCPT ); Sat, 3 Jul 2010 17:47:34 -0400 From: Arnd Bergmann To: Jens Axboe Cc: Christoph Hellwig , linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, John Kacur , Frederic Weisbecker , linux-scsi@vger.kernel.org, Arnd Bergmann , "James E.J. Bottomley" Subject: [PATCH 6/6] scsi/sd: remove big kernel lock Date: Sat, 3 Jul 2010 23:47:20 +0200 Message-Id: <1278193640-24223-7-git-send-email-arnd@arndb.de> X-Mailer: git-send-email 1.7.1 In-Reply-To: <1278193640-24223-1-git-send-email-arnd@arndb.de> References: <1278193640-24223-1-git-send-email-arnd@arndb.de> X-Provags-ID: V01U2FsdGVkX1+u7mdORczmcLni0FAIuT+4HFbAsp9rlVhIgyD hCmcYK6iEXsEyuJQe6BUoJecqpGqWnkqbAq3ZIleVnffvQfOYa zL7iIv83kHLHdYU69+HAQ== Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2628 Lines: 94 Every user of the BKL in the sd driver is the result of the pushdown from the block layer into the open/close/ioctl functions. None of them seem to rely on the BKL, since they do not touch global data without holding another lock, and the open/close functions are still protected from concurrent execution using the bdev->bd_mutex. Signed-off-by: Arnd Bergmann Cc: linux-scsi@vger.kernel.org Cc: "James E.J. Bottomley" --- drivers/scsi/sd.c | 19 +------------------ 1 files changed, 1 insertions(+), 18 deletions(-) diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c index 92702b3..2733068 100644 --- a/drivers/scsi/sd.c +++ b/drivers/scsi/sd.c @@ -758,7 +758,6 @@ static int sd_open(struct block_device *bdev, fmode_t mode) SCSI_LOG_HLQUEUE(3, sd_printk(KERN_INFO, sdkp, "sd_open\n")); - lock_kernel(); sdev = sdkp->device; /* @@ -802,12 +801,10 @@ static int sd_open(struct block_device *bdev, fmode_t mode) scsi_set_medium_removal(sdev, SCSI_REMOVAL_PREVENT); } - unlock_kernel(); return 0; error_out: scsi_disk_put(sdkp); - unlock_kernel(); return retval; } @@ -829,7 +826,6 @@ static int sd_release(struct gendisk *disk, fmode_t mode) SCSI_LOG_HLQUEUE(3, sd_printk(KERN_INFO, sdkp, "sd_release\n")); - lock_kernel(); if (!--sdkp->openers && sdev->removable) { if (scsi_block_when_processing_errors(sdev)) scsi_set_medium_removal(sdev, SCSI_REMOVAL_ALLOW); @@ -840,7 +836,6 @@ static int sd_release(struct gendisk *disk, fmode_t mode) * XXX is followed by a "rmmod sd_mod"? */ scsi_disk_put(sdkp); - unlock_kernel(); return 0; } @@ -921,18 +916,6 @@ static int sd_ioctl(struct block_device *bdev, fmode_t mode, return scsi_ioctl(sdp, cmd, p); } -static int sd_unlocked_ioctl(struct block_device *bdev, fmode_t mode, - unsigned int cmd, unsigned long arg) -{ - int ret; - - lock_kernel(); - ret = sd_ioctl(bdev, mode, cmd, arg); - unlock_kernel(); - - return ret; -} - static void set_media_not_present(struct scsi_disk *sdkp) { sdkp->media_present = 0; @@ -1113,7 +1096,7 @@ static const struct block_device_operations sd_fops = { .owner = THIS_MODULE, .open = sd_open, .release = sd_release, - .ioctl = sd_unlocked_ioctl, + .ioctl = sd_ioctl, .getgeo = sd_getgeo, #ifdef CONFIG_COMPAT .compat_ioctl = sd_compat_ioctl, -- 1.7.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/