From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 79BA7C43387 for ; Tue, 8 Jan 2019 14:53:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4A4E420657 for ; Tue, 8 Jan 2019 14:53:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728185AbfAHOxt (ORCPT ); Tue, 8 Jan 2019 09:53:49 -0500 Received: from mx2.suse.de ([195.135.220.15]:54852 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727662AbfAHOxt (ORCPT ); Tue, 8 Jan 2019 09:53:49 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay1.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 2162DAE76 for ; Tue, 8 Jan 2019 14:53:48 +0000 (UTC) From: Nikolay Borisov To: dsterba@suse.cz Cc: linux-btrfs@vger.kernel.org, Nikolay Borisov Subject: [PATCH v2] btrfs: Remove impossible condition from mergable_maps Date: Tue, 8 Jan 2019 16:53:46 +0200 Message-Id: <20190108145346.24724-1-nborisov@suse.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20190107191019.GD23615@twin.jikos.cz> References: <20190107191019.GD23615@twin.jikos.cz> Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org We can never have extents marked as EXTENT_MAP_DELALLOC since this value is only ever used by btrfs_get_extent_fiemap. In this case the extent map is created by btrfs_get_extent_fiemap and is never really published, this flag is used to return the corresponding userspace one. Considering this, it's pointless having a check for EXTENT_MAP_DELALLOC in mergable_maps. Just remove it. Signed-off-by: Nikolay Borisov --- V2: * Add assert in mergable_maps to ensure EXTENT_MAP_DELALLOC is not set * Clarifty that EXTENT_MAP_DELALLOC is only used during fiemap in a comment fs/btrfs/extent_map.c | 4 ++-- fs/btrfs/extent_map.h | 2 +- 2 files changed, 3 insertions(+), 3 deletions(-) diff --git a/fs/btrfs/extent_map.c b/fs/btrfs/extent_map.c index a042a193c120..c65f208acfb3 100644 --- a/fs/btrfs/extent_map.c +++ b/fs/btrfs/extent_map.c @@ -210,6 +210,8 @@ static int mergable_maps(struct extent_map *prev, struct extent_map *next) if (!list_empty(&prev->list) || !list_empty(&next->list)) return 0; + ASSERT(next->block_start != EXTENT_MAP_DELALLOC && + prev->block_start != EXTENT_MAP_DELALLOC); if (extent_map_end(prev) == next->start && prev->flags == next->flags && prev->bdev == next->bdev && @@ -217,8 +219,6 @@ static int mergable_maps(struct extent_map *prev, struct extent_map *next) prev->block_start == EXTENT_MAP_HOLE) || (next->block_start == EXTENT_MAP_INLINE && prev->block_start == EXTENT_MAP_INLINE) || - (next->block_start == EXTENT_MAP_DELALLOC && - prev->block_start == EXTENT_MAP_DELALLOC) || (next->block_start < EXTENT_MAP_LAST_BYTE - 1 && next->block_start == extent_map_block_end(prev)))) { return 1; diff --git a/fs/btrfs/extent_map.h b/fs/btrfs/extent_map.h index ef05a0121652..9ef8766f478a 100644 --- a/fs/btrfs/extent_map.h +++ b/fs/btrfs/extent_map.h @@ -9,7 +9,7 @@ #define EXTENT_MAP_LAST_BYTE ((u64)-4) #define EXTENT_MAP_HOLE ((u64)-3) #define EXTENT_MAP_INLINE ((u64)-2) -#define EXTENT_MAP_DELALLOC ((u64)-1) +#define EXTENT_MAP_DELALLOC ((u64)-1) /* used only during fiemap calls */ /* bits for the extent_map::flags field */ enum { -- 2.17.1