From patchwork Tue Jun 9 09:40:12 2009 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: gregkh@suse.de X-Patchwork-Id: 28295 Return-Path: X-Original-To: patchwork-incoming@bilbo.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from ozlabs.org (ozlabs.org [203.10.76.45]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "mx.ozlabs.org", Issuer "CA Cert Signing Authority" (verified OK)) by bilbo.ozlabs.org (Postfix) with ESMTPS id 225FEB70C3 for ; Tue, 9 Jun 2009 20:25:53 +1000 (EST) Received: by ozlabs.org (Postfix) id 1541EDDD0B; Tue, 9 Jun 2009 20:25:53 +1000 (EST) Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.176.167]) by ozlabs.org (Postfix) with ESMTP id 96B5EDDD04 for ; Tue, 9 Jun 2009 20:25:52 +1000 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757719AbZFIKW1 (ORCPT ); Tue, 9 Jun 2009 06:22:27 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1758066AbZFIKW0 (ORCPT ); Tue, 9 Jun 2009 06:22:26 -0400 Received: from kroah.org ([198.145.64.141]:32894 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757622AbZFIKWX (ORCPT ); Tue, 9 Jun 2009 06:22:23 -0400 Received: from localhost (59-124-51-242.HINET-IP.hinet.net [59.124.51.242]) (using TLSv1 with cipher DHE-RSA-AES128-SHA (128/128 bits)) (No client certificate requested) by coco.kroah.org (Postfix) with ESMTPSA id 3CC4249134; Tue, 9 Jun 2009 03:22:25 -0700 (PDT) X-Mailbox-Line: From greg@blue.kroah.org Tue Jun 9 02:41:12 2009 Message-Id: <20090609094112.103140898@blue.kroah.org> User-Agent: quilt/0.48-1 Date: Tue, 09 Jun 2009 02:40:12 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: Justin Forbes , Zwane Mwaikambo , Theodore Ts'o , Randy Dunlap , Dave Jones , Chuck Wolber , Chris Wedgwood , Michael Krufky , Chuck Ebbert , Domenico Andreoli , Willy Tarreau , Rodrigo Rubira Branco , Jake Edge , Eugene Teo , torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, linux-ext4@vger.kernel.org, "Aneesh Kumar K.V" , Greg Kroah-Hartman Subject: [patch 84/87] ext4: Fix sub-block zeroing for writes into preallocated extents References: <20090609093848.204935043@blue.kroah.org> Content-Disposition: inline; filename=ext4-fix-sub-block-zeroing-for-writes-into-preallocated-extents.patch Lines: 50 In-Reply-To: <20090609094451.GA26439@kroah.com> Sender: linux-ext4-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-ext4@vger.kernel.org 2.6.29-stable review patch. If anyone has any objections, please let us know. ------------------ From: Aneesh Kumar K.V (cherry picked from commit 9c1ee184a30394e54165fa4c15923cabd952c106) We need to mark the buffer_head mapping preallocated space as new during write_begin. Otherwise we don't zero out the page cache content properly for a partial write. This will cause file corruption with preallocation. Now that we mark the buffer_head new we also need to have a valid buffer_head blocknr so that unmap_underlying_metadata() unmaps the correct block. Signed-off-by: Aneesh Kumar K.V Signed-off-by: "Theodore Ts'o" Signed-off-by: Greg Kroah-Hartman --- fs/ext4/extents.c | 2 ++ fs/ext4/inode.c | 7 +++++++ 2 files changed, 9 insertions(+) -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html --- a/fs/ext4/extents.c +++ b/fs/ext4/extents.c @@ -2776,6 +2776,8 @@ int ext4_ext_get_blocks(handle_t *handle if (allocated > max_blocks) allocated = max_blocks; set_buffer_unwritten(bh_result); + bh_result->b_bdev = inode->i_sb->s_bdev; + bh_result->b_blocknr = newblock; goto out2; } --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -2246,6 +2246,13 @@ static int ext4_da_get_block_prep(struct set_buffer_delay(bh_result); } else if (ret > 0) { bh_result->b_size = (ret << inode->i_blkbits); + /* + * With sub-block writes into unwritten extents + * we also need to mark the buffer as new so that + * the unwritten parts of the buffer gets correctly zeroed. + */ + if (buffer_unwritten(bh_result)) + set_buffer_new(bh_result); ret = 0; }