From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Cyrus-Session-Id: sloti22d1t05-1098017-1521804170-2-14609813343482828071 X-Sieve: CMU Sieve 3.0 X-Spam-known-sender: no X-Spam-score: 0.0 X-Spam-hits: BAYES_00 -1.9, HEADER_FROM_DIFFERENT_DOMAINS 0.25, ME_NOAUTH 0.01, RCVD_IN_DNSWL_HI -5, T_RP_MATCHES_RCVD -0.01, LANGUAGES en, BAYES_USED global, SA_VERSION 3.4.0 X-Spam-source: IP='209.132.180.67', Host='vger.kernel.org', Country='CN', FromHeader='org', MailFrom='org' X-Spam-charsets: plain='UTF-8' X-Resolved-to: greg@kroah.com X-Delivered-to: greg@kroah.com X-Mail-from: stable-owner@vger.kernel.org ARC-Seal: i=1; a=rsa-sha256; cv=none; d=messagingengine.com; s=arctest; t=1521804169; b=jaZUulE+qgqYV/Oz47/akUmfF64jPxPo3VOcKJ417qsYmle dFgrSKW0AAsA/8jPz7Imzpyp5vtuzSbb+YSWLUZNYhFBFEEXv6XN/SsLcEs7Wf9f Rt6D6E3/fJW/YhXSMpgiCU1iLITCWVO5vHiJH4rR6PeSuaEcdtJv0L/JH5kzWs0U cHNn+C2DNXLlx3ADJYykn6MVqHbnr9cQ2bd9/OUuDOKG1zk57U7SVGt3zVVNmhrO swXA98xD3z23hlLKsx+G8vjmQDEMHvnAFzFobVZA3o76S/BSMLGtUGK+7UXssJqa t7C9jzFwt89C/Q567ZuT2V4E8y/eQ7RlXE8v6yQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=from:to:cc:subject:date:message-id :in-reply-to:references:mime-version:content-type:sender :list-id; s=arctest; t=1521804169; bh=kdI0BQu38fxa4oO9yGPTzr5eU0 7cla9PszG5pe2L6Fk=; b=Z+8E40ttaN8whduiNPEpeo2FDvENNGc/qcrrrwUVHH WcV6JtIKV2KJYqUMdpDXB9k++NDGd70knEtCuP+qWD4BumqaIGKZelQk4u6xsmN+ LckNMLwZz3Eflmx3AthytnTmKGP1sDWnv1pRpIHB3PIAwfw8yqzHjQply/vUnXwS 8EY7hEoi4UgyRMAv8Xx2czFJhSeoEcWYC2q089e/JNLhPM1AA1aXfKV3Ne3Nk4hs 4pHFM+9gi/uVbKOX5tfNHm78rhZup2XTvCwNrYX4QzL8lpna7y+ZC0HHci2HLigr tUbxrtt+kiIk5Whnc4/DP8/Uab0s0wQ9yPamrMd79yUA== ARC-Authentication-Results: i=1; mx2.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=linuxfoundation.org; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=linuxfoundation.org header.result=pass header_is_org_domain=yes; x-vs=clean score=-100 state=0 Authentication-Results: mx2.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=linuxfoundation.org; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=linuxfoundation.org header.result=pass header_is_org_domain=yes; x-vs=clean score=-100 state=0 X-ME-VSCategory: clean Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751730AbeCWLWd (ORCPT ); Fri, 23 Mar 2018 07:22:33 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:41576 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755474AbeCWKIK (ORCPT ); Fri, 23 Mar 2018 06:08:10 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Filipe Manana , Liu Bo , Sasha Levin Subject: [PATCH 4.9 077/177] Btrfs: send, fix file hole not being preserved due to inline extent Date: Fri, 23 Mar 2018 10:53:25 +0100 Message-Id: <20180323094208.708796451@linuxfoundation.org> X-Mailer: git-send-email 2.16.2 In-Reply-To: <20180323094205.090519271@linuxfoundation.org> References: <20180323094205.090519271@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org X-Mailing-List: stable@vger.kernel.org X-getmail-retrieved-from-mailbox: INBOX X-Mailing-List: linux-kernel@vger.kernel.org List-ID: 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Filipe Manana [ Upstream commit e1cbfd7bf6dabdac561c75d08357571f44040a45 ] Normally we don't have inline extents followed by regular extents, but there's currently at least one harmless case where this happens. For example, when the page size is 4Kb and compression is enabled: $ mkfs.btrfs -f /dev/sdb $ mount -o compress /dev/sdb /mnt $ xfs_io -f -c "pwrite -S 0xaa 0 4K" -c "fsync" /mnt/foobar $ xfs_io -c "pwrite -S 0xbb 8K 4K" -c "fsync" /mnt/foobar In this case we get a compressed inline extent, representing 4Kb of data, followed by a hole extent and then a regular data extent. The inline extent was not expanded/converted to a regular extent exactly because it represents 4Kb of data. This does not cause any apparent problem (such as the issue solved by commit e1699d2d7bf6 ("btrfs: add missing memset while reading compressed inline extents")) except trigger an unexpected case in the incremental send code path that makes us issue an operation to write a hole when it's not needed, resulting in more writes at the receiver and wasting space at the receiver. So teach the incremental send code to deal with this particular case. The issue can be currently triggered by running fstests btrfs/137 with compression enabled (MOUNT_OPTIONS="-o compress" ./check btrfs/137). Signed-off-by: Filipe Manana Reviewed-by: Liu Bo Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- fs/btrfs/send.c | 23 +++++++++++++++++++++-- 1 file changed, 21 insertions(+), 2 deletions(-) --- a/fs/btrfs/send.c +++ b/fs/btrfs/send.c @@ -5156,13 +5156,19 @@ static int is_extent_unchanged(struct se while (key.offset < ekey->offset + left_len) { ei = btrfs_item_ptr(eb, slot, struct btrfs_file_extent_item); right_type = btrfs_file_extent_type(eb, ei); - if (right_type != BTRFS_FILE_EXTENT_REG) { + if (right_type != BTRFS_FILE_EXTENT_REG && + right_type != BTRFS_FILE_EXTENT_INLINE) { ret = 0; goto out; } right_disknr = btrfs_file_extent_disk_bytenr(eb, ei); - right_len = btrfs_file_extent_num_bytes(eb, ei); + if (right_type == BTRFS_FILE_EXTENT_INLINE) { + right_len = btrfs_file_extent_inline_len(eb, slot, ei); + right_len = PAGE_ALIGN(right_len); + } else { + right_len = btrfs_file_extent_num_bytes(eb, ei); + } right_offset = btrfs_file_extent_offset(eb, ei); right_gen = btrfs_file_extent_generation(eb, ei); @@ -5176,6 +5182,19 @@ static int is_extent_unchanged(struct se goto out; } + /* + * We just wanted to see if when we have an inline extent, what + * follows it is a regular extent (wanted to check the above + * condition for inline extents too). This should normally not + * happen but it's possible for example when we have an inline + * compressed extent representing data with a size matching + * the page size (currently the same as sector size). + */ + if (right_type == BTRFS_FILE_EXTENT_INLINE) { + ret = 0; + goto out; + } + left_offset_fixed = left_offset; if (key.offset < ekey->offset) { /* Fix the right offset for 2a and 7. */