From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx2.suse.de ([195.135.220.15]:35493 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751422AbdHXLr7 (ORCPT ); Thu, 24 Aug 2017 07:47:59 -0400 From: Nikolay Borisov Subject: [PATCH 6/6] fiemap: Fix semantics of max_extents (-n arguments) Date: Thu, 24 Aug 2017 14:47:52 +0300 Message-Id: <1503575272-28263-7-git-send-email-nborisov@suse.com> In-Reply-To: <1503575272-28263-1-git-send-email-nborisov@suse.com> References: <1503575272-28263-1-git-send-email-nborisov@suse.com> Sender: linux-xfs-owner@vger.kernel.org List-ID: List-Id: xfs To: linux-xfs@vger.kernel.org Cc: sandeen@redhat.com, Nikolay Borisov Currently the semantics of the -n argument are a bit idiosyncratic. We want the argument to be the limit of extents that are going to be output by the tool. This is clearly broken now as evident from the following example on a fragmented file: xfs_io -c "fiemap -v -n 5" test-dir/fragmented-file test-dir/fragmented-file: EXT: FILE-OFFSET BLOCK-RANGE TOTAL FLAGS 0: [0..15]: hole 16 1: [16..23]: 897847296..897847303 8 0x0 2: [24..31]: hole 8 3: [32..39]: 897851392..897851399 8 0x0 So we want at most 5 extents printed, yet we get 4. So we always print n - 1 extents. With this modification the output looks like: xfs_io -c "fiemap -v -n 5" test-dir/fragmented-file test-dir/fragmented-file: EXT: FILE-OFFSET BLOCK-RANGE TOTAL FLAGS 0: [0..15]: hole 16 1: [16..23]: 897847296..897847303 8 0x0 2: [24..31]: hole 8 3: [32..39]: 897851392..897851399 8 0x0 4: [40..47]: hole 8 Signed-off-by: Nikolay Borisov --- io/fiemap.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/io/fiemap.c b/io/fiemap.c index 44a64870d711..7b275275465d 100644 --- a/io/fiemap.c +++ b/io/fiemap.c @@ -122,7 +122,7 @@ print_verbose( cur_extent++; } - if ((cur_extent + 1) == max_extents) + if (cur_extent == max_extents) return 1; snprintf(lbuf, sizeof(lbuf), "[%llu..%llu]:", lstart, @@ -157,7 +157,7 @@ print_plain( cur_extent++; } - if ((cur_extent + 1) == max_extents) + if (cur_extent == max_extents) return 1; printf("\t%d: [%llu..%llu]: %llu..%llu", cur_extent, @@ -264,7 +264,7 @@ fiemap_f( printf("%s:\n", file->name); - while (!last && ((cur_extent + 1) != max_extents)) { + while (!last && (cur_extent != max_extents)) { memset(fiemap, 0, map_size); fiemap->fm_flags = fiemap_flags; @@ -314,12 +314,12 @@ fiemap_f( break; } - if ((cur_extent + 1) == max_extents) + if (cur_extent == max_extents) break; } } - if ((cur_extent + 1) == max_extents) + if (cur_extent == max_extents) goto out; memset(&st, 0, sizeof(st)); -- 2.7.4