From patchwork Thu Feb 22 12:45:48 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yu Kuai X-Patchwork-Id: 13567245 Received: from dggsgout12.his.huawei.com (dggsgout12.his.huawei.com [45.249.212.56]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 774A612FF60; Thu, 22 Feb 2024 12:51:40 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.249.212.56 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1708606303; cv=none; b=S+R+v41T+LnOFpgOQdmEGyhohw8cTLjakmY3HVnJsIvFC/JeXPn7/Vjr7+GRJ5CKej8VW6zYgZn1PQ530iqIY6j/6jfaxjWyv46u/I6PXddGTpS+cNBph2Y8lb9X8vi0B2lFOLJI2ayl8sqdLDml928OZT6tf3Bm01n6QXf/TCk= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1708606303; c=relaxed/simple; bh=/CDu+7gVV8uktwKlCCSmA+xIKRNTNm0Kl1wXR19U5pw=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=GdrbYMIfbubrFBXO/Pf/U0DzxXCTtWEF6sMYKoic8i+o4bQxNKZ83pJRlGttEXHTq+v2oufHMVgUqgcRA9yqu7WAiadQoAO9HrAACOO2UZxMFPoWzFA8WbRDohsVKgo/Z+DMxk3aBFJTIjTXTYLcgZlpKzZ/6BewiQ8uvE1rA9o= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=huaweicloud.com; spf=pass smtp.mailfrom=huaweicloud.com; arc=none smtp.client-ip=45.249.212.56 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=huaweicloud.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huaweicloud.com Received: from mail.maildlp.com (unknown [172.19.163.235]) by dggsgout12.his.huawei.com (SkyGuard) with ESMTP id 4TgY1J5j5Vz4f3kFP; Thu, 22 Feb 2024 20:51:32 +0800 (CST) Received: from mail02.huawei.com (unknown [10.116.40.112]) by mail.maildlp.com (Postfix) with ESMTP id CCCE71A0232; Thu, 22 Feb 2024 20:51:37 +0800 (CST) Received: from huaweicloud.com (unknown [10.175.104.67]) by APP1 (Coremail) with SMTP id cCh0CgBHGBFSQ9dlQ382Ew--.47909S16; Thu, 22 Feb 2024 20:51:37 +0800 (CST) From: Yu Kuai To: jack@suse.cz, hch@lst.de, brauner@kernel.org, axboe@kernel.dk Cc: linux-fsdevel@vger.kernel.org, linux-block@vger.kernel.org, yukuai3@huawei.com, yukuai1@huaweicloud.com, yi.zhang@huawei.com, yangerkun@huawei.com Subject: [RFC v4 linux-next 12/19] ext4: remove block_device_ejected() Date: Thu, 22 Feb 2024 20:45:48 +0800 Message-Id: <20240222124555.2049140-13-yukuai1@huaweicloud.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20240222124555.2049140-1-yukuai1@huaweicloud.com> References: <20240222124555.2049140-1-yukuai1@huaweicloud.com> Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-CM-TRANSID: cCh0CgBHGBFSQ9dlQ382Ew--.47909S16 X-Coremail-Antispam: 1UD129KBjvJXoW7Kr4UGw1xJF1fWr48KFy3urg_yoW8tF1Up3 y3uw1xJrW8urn29ayxJr4xW340qa92kay0gFyxur1Fgrn3Jry0vF4ktr4Iya40vrZ3uw4F qF1UCrWxCr18CrDanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUPI14x267AKxVWrJVCq3wAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2048vs2IY020E87I2jVAFwI0_JF0E3s1l82xGYI kIc2x26xkF7I0E14v26ryj6s0DM28lY4IEw2IIxxk0rwA2F7IY1VAKz4vEj48ve4kI8wA2 z4x0Y4vE2Ix0cI8IcVAFwI0_Xr0_Ar1l84ACjcxK6xIIjxv20xvEc7CjxVAFwI0_Gr1j6F 4UJwA2z4x0Y4vEx4A2jsIE14v26rxl6s0DM28EF7xvwVC2z280aVCY1x0267AKxVW0oVCq 3wAS0I0E0xvYzxvE52x082IY62kv0487Mc02F40EFcxC0VAKzVAqx4xG6I80ewAv7VC0I7 IYx2IY67AKxVWUJVWUGwAv7VC2z280aVAFwI0_Jr0_Gr1lOx8S6xCaFVCjc4AY6r1j6r4U M4x0Y48IcxkI7VAKI48JM4x0x7Aq67IIx4CEVc8vx2IErcIFxwACI402YVCY1x02628vn2 kIc2xKxwCF04k20xvY0x0EwIxGrwCFx2IqxVCFs4IE7xkEbVWUJVW8JwC20s026c02F40E 14v26r1j6r18MI8I3I0E7480Y4vE14v26r106r1rMI8E67AF67kF1VAFwI0_Jw0_GFylIx kGc2Ij64vIr41lIxAIcVC0I7IYx2IY67AKxVW8JVW5JwCI42IY6xIIjxv20xvEc7CjxVAF wI0_Gr1j6F4UJwCI42IY6xAIw20EY4v20xvaj40_Jr0_JF4lIxAIcVC2z280aVAFwI0_Gr 0_Cr1lIxAIcVC2z280aVCY1x0267AKxVW8Jr0_Cr1UYxBIdaVFxhVjvjDU0xZFpf9x0JUQ SdkUUUUU= X-CM-SenderInfo: 51xn3trlr6x35dzhxuhorxvhhfrp/ From: Yu Kuai block_device_ejected() is added by commit bdfe0cbd746a ("Revert "ext4: remove block_device_ejected"") in 2015. At that time 'bdi->wb' is destroyed synchronized from del_gendisk(), hence if ext4 is still mounted, and then mark_buffer_dirty() will reference destroyed 'wb'. However, such problem doesn't exist anymore: - commit d03f6cdc1fc4 ("block: Dynamically allocate and refcount backing_dev_info") switch bdi to use refcounting; - commit 13eec2363ef0 ("fs: Get proper reference for s_bdi"), will grab additional reference of bdi while mounting, so that 'bdi->wb' will not be destroyed until generic_shutdown_super(). Hence remove this dead function block_device_ejected(). Signed-off-by: Yu Kuai Reviewed-by: Jan Kara Reviewed-by: Christoph Hellwig --- fs/ext4/super.c | 18 ------------------ 1 file changed, 18 deletions(-) diff --git a/fs/ext4/super.c b/fs/ext4/super.c index e487623f9456..2d82b9d4b079 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -492,22 +492,6 @@ static void ext4_maybe_update_superblock(struct super_block *sb) schedule_work(&EXT4_SB(sb)->s_sb_upd_work); } -/* - * The del_gendisk() function uninitializes the disk-specific data - * structures, including the bdi structure, without telling anyone - * else. Once this happens, any attempt to call mark_buffer_dirty() - * (for example, by ext4_commit_super), will cause a kernel OOPS. - * This is a kludge to prevent these oops until we can put in a proper - * hook in del_gendisk() to inform the VFS and file system layers. - */ -static int block_device_ejected(struct super_block *sb) -{ - struct inode *bd_inode = sb->s_bdev->bd_inode; - struct backing_dev_info *bdi = inode_to_bdi(bd_inode); - - return bdi->dev == NULL; -} - static void ext4_journal_commit_callback(journal_t *journal, transaction_t *txn) { struct super_block *sb = journal->j_private; @@ -6176,8 +6160,6 @@ static int ext4_commit_super(struct super_block *sb) if (!sbh) return -EINVAL; - if (block_device_ejected(sb)) - return -ENODEV; ext4_update_super(sb);