From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D5C9BC43381 for ; Mon, 4 Mar 2019 08:23:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A3F7D208E4 for ; Mon, 4 Mar 2019 08:23:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1551687789; bh=Im0ccbENMgSHBPMue2rd/5Y3/QnWDRL2qIYLBe9PlS0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=Zv9cx9JfL1M4oNwdFYGcuB5Y5og+NkRq4ZPjyXE3L5TpH/ab9MsZDwhnZRJuzbARP eK9mdXNf2UG8yfyjtBjlgTKOv1jzNjPfy+da2JQw0sHLZm/hbVZssS4Spt01eRQrTA 3LeIGRaU2aa4P7mH/iyl91eQZtRe7+2zy0ADp6AQ= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726465AbfCDIXI (ORCPT ); Mon, 4 Mar 2019 03:23:08 -0500 Received: from mail.kernel.org ([198.145.29.99]:38388 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726128AbfCDIXG (ORCPT ); Mon, 4 Mar 2019 03:23:06 -0500 Received: from localhost (5356596B.cm-6-7b.dynamic.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 30BDB20823; Mon, 4 Mar 2019 08:23:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1551687785; bh=Im0ccbENMgSHBPMue2rd/5Y3/QnWDRL2qIYLBe9PlS0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Xa8McjZRo9WlvHkt33H8zv0SRKe2U8tnN+he8ZmyfMyxJXhieJuIqNujirOcy1tys BzvQUsSLrNVkE9NAazKPDN48W77EMh2ezzoQG1fl4mWMNgM4U+J+gfRpiwtBFfOD1J TC8PuNStSOTq/vWrfXqGKFWBTU2cn8EO6FGOwWdE= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Thomas Lindroth , Jan Kara , Jens Axboe Subject: [PATCH 4.9 02/32] Revert "loop: Get rid of loop_index_mutex" Date: Mon, 4 Mar 2019 09:21:50 +0100 Message-Id: <20190304081602.478558699@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190304081602.307094059@linuxfoundation.org> References: <20190304081602.307094059@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Greg Kroah-Hartman This reverts commit 6a8f1d8d701462937ce01a3f2219af5435372af7 which is commit 0a42e99b58a208839626465af194cfe640ef9493 upstream. It does not work properly in the 4.9.y tree and causes more problems than it fixes, so revert it. Reported-by: Thomas Lindroth Reported-by: Jan Kara Cc: Jens Axboe Signed-off-by: Greg Kroah-Hartman --- drivers/block/loop.c | 39 +++++++++++++++++++-------------------- 1 file changed, 19 insertions(+), 20 deletions(-) --- a/drivers/block/loop.c +++ b/drivers/block/loop.c @@ -81,6 +81,7 @@ #include static DEFINE_IDR(loop_index_idr); +static DEFINE_MUTEX(loop_index_mutex); static DEFINE_MUTEX(loop_ctl_mutex); static int max_part; @@ -1559,11 +1560,9 @@ static int lo_compat_ioctl(struct block_ static int lo_open(struct block_device *bdev, fmode_t mode) { struct loop_device *lo; - int err; + int err = 0; - err = mutex_lock_killable(&loop_ctl_mutex); - if (err) - return err; + mutex_lock(&loop_index_mutex); lo = bdev->bd_disk->private_data; if (!lo) { err = -ENXIO; @@ -1572,7 +1571,7 @@ static int lo_open(struct block_device * atomic_inc(&lo->lo_refcnt); out: - mutex_unlock(&loop_ctl_mutex); + mutex_unlock(&loop_index_mutex); return err; } @@ -1581,11 +1580,12 @@ static void lo_release(struct gendisk *d struct loop_device *lo; int err; - mutex_lock(&loop_ctl_mutex); + mutex_lock(&loop_index_mutex); lo = disk->private_data; if (atomic_dec_return(&lo->lo_refcnt)) - goto out_unlock; + goto unlock_index; + mutex_lock(&loop_ctl_mutex); if (lo->lo_flags & LO_FLAGS_AUTOCLEAR) { /* * In autoclear mode, stop the loop thread @@ -1593,7 +1593,7 @@ static void lo_release(struct gendisk *d */ err = loop_clr_fd(lo); if (!err) - return; + goto unlock_index; } else { /* * Otherwise keep thread (if running) and config, @@ -1602,8 +1602,9 @@ static void lo_release(struct gendisk *d loop_flush(lo); } -out_unlock: mutex_unlock(&loop_ctl_mutex); +unlock_index: + mutex_unlock(&loop_index_mutex); } static const struct block_device_operations lo_fops = { @@ -1889,7 +1890,7 @@ static struct kobject *loop_probe(dev_t struct kobject *kobj; int err; - mutex_lock(&loop_ctl_mutex); + mutex_lock(&loop_index_mutex); err = loop_lookup(&lo, MINOR(dev) >> part_shift); if (err < 0) err = loop_add(&lo, MINOR(dev) >> part_shift); @@ -1897,7 +1898,7 @@ static struct kobject *loop_probe(dev_t kobj = NULL; else kobj = get_disk(lo->lo_disk); - mutex_unlock(&loop_ctl_mutex); + mutex_unlock(&loop_index_mutex); *part = 0; return kobj; @@ -1907,13 +1908,9 @@ static long loop_control_ioctl(struct fi unsigned long parm) { struct loop_device *lo; - int ret; - - ret = mutex_lock_killable(&loop_ctl_mutex); - if (ret) - return ret; + int ret = -ENOSYS; - ret = -ENOSYS; + mutex_lock(&loop_index_mutex); switch (cmd) { case LOOP_CTL_ADD: ret = loop_lookup(&lo, parm); @@ -1927,6 +1924,7 @@ static long loop_control_ioctl(struct fi ret = loop_lookup(&lo, parm); if (ret < 0) break; + mutex_lock(&loop_ctl_mutex); if (lo->lo_state != Lo_unbound) { ret = -EBUSY; mutex_unlock(&loop_ctl_mutex); @@ -1938,6 +1936,7 @@ static long loop_control_ioctl(struct fi break; } lo->lo_disk->private_data = NULL; + mutex_unlock(&loop_ctl_mutex); idr_remove(&loop_index_idr, lo->lo_number); loop_remove(lo); break; @@ -1947,7 +1946,7 @@ static long loop_control_ioctl(struct fi break; ret = loop_add(&lo, -1); } - mutex_unlock(&loop_ctl_mutex); + mutex_unlock(&loop_index_mutex); return ret; } @@ -2030,10 +2029,10 @@ static int __init loop_init(void) THIS_MODULE, loop_probe, NULL, NULL); /* pre-create number of devices given by config or max_loop */ - mutex_lock(&loop_ctl_mutex); + mutex_lock(&loop_index_mutex); for (i = 0; i < nr; i++) loop_add(&lo, i); - mutex_unlock(&loop_ctl_mutex); + mutex_unlock(&loop_index_mutex); printk(KERN_INFO "loop: module loaded\n"); return 0;