From patchwork Wed Mar 7 08:20:18 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: robbieko X-Patchwork-Id: 10263597 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id A089660211 for ; Wed, 7 Mar 2018 08:22:13 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 8C430292F9 for ; Wed, 7 Mar 2018 08:22:13 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 80A9A29302; Wed, 7 Mar 2018 08:22:13 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=2.0 tests=BAYES_00,DKIM_SIGNED, RCVD_IN_DNSWL_HI,T_DKIM_INVALID autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id E72E5292F9 for ; Wed, 7 Mar 2018 08:22:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933493AbeCGIV7 (ORCPT ); Wed, 7 Mar 2018 03:21:59 -0500 Received: from synology.com ([59.124.61.242]:37483 "EHLO synology.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933209AbeCGIVG (ORCPT ); Wed, 7 Mar 2018 03:21:06 -0500 Received: from localhost.localdomain (unknown [10.13.20.241]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA256 (128/128 bits)) (No client certificate requested) by synology.com (Postfix) with ESMTPSA id ED9478093FFD; Wed, 7 Mar 2018 16:21:04 +0800 (CST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=synology.com; s=123; t=1520410865; bh=4w6GPzkiC6AKIUUo9rGVwzUPNll7lOCDt2/XfFLykqU=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=KU0HL/yItKNuvlg4PWvcabYQgXCY95vx2Ub6tuY2Aup0iJ8vUJoXiKLc+efTPU9Be QzziY3QbNHRnp2y/7Geql8vtBmEjok7sK/bc49YY/amO9O//dNUmv286MVrs82Ojgt A4Ygme2Nrl9XJLy9LvfCw0C3/DxYUY6JlmLawHDM= From: robbieko To: linux-btrfs@vger.kernel.org Cc: Robbie Ko Subject: [PATCH 1/2] Btrfs: fiemap: pass correct bytenr when fm_extent_count is zero Date: Wed, 7 Mar 2018 16:20:18 +0800 Message-Id: <1520410819-32405-2-git-send-email-robbieko@synology.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1520410819-32405-1-git-send-email-robbieko@synology.com> References: <1520410819-32405-1-git-send-email-robbieko@synology.com> X-Synology-MCP-Status: no X-Synology-Spam-Flag: no X-Synology-Spam-Status: score=0, required 5, WHITELIST_FROM_ADDRESS 0 X-Synology-Virus-Status: no Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Robbie Ko # mount /dev/vdb5 /mnt/btrfs # dd if=/dev/zero bs=16K count=4 oflag=dsync of=/mnt/btrfs/file # xfs_io -c "fiemap -v" /mnt/btrfs/file /mnt/btrfs/file: EXT: FILE-OFFSET BLOCK-RANGE TOTAL FLAGS 0: [0..127]: 25088..25215 128 0x1 Run fiemap with fm_extent_count set to 0, we'll get wrong value 4 instead of 1. [REASON] When fm_extent_count is 0, disko is not initialized correctly, The value is 0 in this case, not the right bytenr. [FIX] Use correct disko. Signed-off-by: Robbie Ko --- fs/btrfs/extent_io.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c index 012d638..066b6df 100644 --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -4567,7 +4567,7 @@ int extent_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo, offset_in_extent = em_start - em->start; em_end = extent_map_end(em); em_len = em_end - em_start; - disko = 0; + disko = em->block_start + offset_in_extent; flags = 0; /* @@ -4590,8 +4590,6 @@ int extent_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo, u64 bytenr = em->block_start - (em->start - em->orig_start); - disko = em->block_start + offset_in_extent; - /* * As btrfs supports shared space, this information * can be exported to userspace tools via