From patchwork Thu Apr 11 14:53:42 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Al Viro X-Patchwork-Id: 13626124 Received: from zeniv.linux.org.uk (zeniv.linux.org.uk [62.89.141.173]) (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 035B8171A2; Thu, 11 Apr 2024 14:53:58 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=62.89.141.173 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712847240; cv=none; b=TGNxN3j083tObFC5C6kWoJPEQ4bhISASDlKu3OOpeSSwoFXVQpfWKmXgVkFVWbazZTfm1UdmpTvznDOckXwHRbF75MNIU0ghg6Z68BeocTMvB7GVcY32drDwEmIj8c3UeGz8akDVYMSTCzegJmMSw/kZyynAYL81ia5fINl+ELs= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712847240; c=relaxed/simple; bh=ap3oFZBBuXW17h6a4e4Umhs2ROBQwDIde/NaY9FQPrw=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=Y7BHfif+HWzO+Htganzr/nCq4/xX1+KVZUSPjdlNpKUzSNd3uk1Ne24z+WoKuAaJbhrC7dTCF8ju4SNI9dEBV3+6B46lRhnewU2dByju3HLoD4h7xuPFPkYisBBuSNPK/qPoQv+gasKSAXMVKZDEqCNdbfHGuV/4d81oWZ4TtmQ= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=zeniv.linux.org.uk; spf=none smtp.mailfrom=ftp.linux.org.uk; dkim=pass (2048-bit key) header.d=linux.org.uk header.i=@linux.org.uk header.b=Vuvi3kUW; arc=none smtp.client-ip=62.89.141.173 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=zeniv.linux.org.uk Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=ftp.linux.org.uk Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linux.org.uk header.i=@linux.org.uk header.b="Vuvi3kUW" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=linux.org.uk; s=zeniv-20220401; h=Sender:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description; bh=yZdLjG/il+GlaYVgNdZTGvNnsUIUXz0bS4lPZX5rpxg=; b=Vuvi3kUW5dqJ3/fl3YxgenW8Pl VMyctbFk1qGFIIm5Xcz5EXUaRHxLJAH3pe/b15XV0fLOwFX4/wRHpegN0TiRSfoStSM5/yivPvZZ9 TGGkY6gLnYsJadF5Q1BB1VFVVa1E6PyfQWBruQuMLXKF+Ivfxuq+Rs6dzteeJBim4KyWSilwVwf1w cxUKfaBL3VX3/u3bp40g9hqCZeTCWZpO3tSvGw22+5RIi2jtD/u5JGoO4M+MCT060R8u5Va203vkD c4q8cRkxxwp2zgMpW57GpL+eQ6TZd5K6ffDwHD0bW0Goc4Ho9TyGIIKgwa+yxjLREo1qphPUtBafG IqzmPhjg==; Received: from viro by zeniv.linux.org.uk with local (Exim 4.96 #2 (Red Hat Linux)) id 1ruvoB-00AYko-1B; Thu, 11 Apr 2024 14:53:47 +0000 From: Al Viro To: Christian Brauner Cc: Jan Kara , Yu Kuai , hch@lst.de, axboe@kernel.dk, linux-fsdevel@vger.kernel.org, linux-block@vger.kernel.org, yi.zhang@huawei.com, yangerkun@huawei.com, "yukuai (C)" Subject: [PATCH 07/11] ext4: remove block_device_ejected() Date: Thu, 11 Apr 2024 15:53:42 +0100 Message-Id: <20240411145346.2516848-7-viro@zeniv.linux.org.uk> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20240411145346.2516848-1-viro@zeniv.linux.org.uk> References: <20240411144930.GI2118490@ZenIV> <20240411145346.2516848-1-viro@zeniv.linux.org.uk> Precedence: bulk X-Mailing-List: linux-block@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Sender: Al Viro 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 Signed-off-by: Al Viro --- fs/ext4/super.c | 18 ------------------ 1 file changed, 18 deletions(-) diff --git a/fs/ext4/super.c b/fs/ext4/super.c index 0be1c3a7ffa0..6e2bd802b50c 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; @@ -6168,8 +6152,6 @@ static int ext4_commit_super(struct super_block *sb) if (!sbh) return -EINVAL; - if (block_device_ejected(sb)) - return -ENODEV; ext4_update_super(sb);