From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from fgwmail6.fujitsu.co.jp ([192.51.44.36]:55958 "EHLO fgwmail6.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751365AbaHKXza (ORCPT ); Mon, 11 Aug 2014 19:55:30 -0400 Received: from kw-mxauth.gw.nic.fujitsu.com (unknown [10.0.237.134]) by fgwmail6.fujitsu.co.jp (Postfix) with ESMTP id 466C13EE0AE for ; Tue, 12 Aug 2014 08:55:28 +0900 (JST) Received: from s1.gw.fujitsu.co.jp (s1.gw.fujitsu.co.jp [10.0.50.91]) by kw-mxauth.gw.nic.fujitsu.com (Postfix) with ESMTP id 5DDF4AC0538 for ; Tue, 12 Aug 2014 08:55:27 +0900 (JST) Received: from g01jpfmpwyt01.exch.g01.fujitsu.local (g01jpfmpwyt01.exch.g01.fujitsu.local [10.128.193.38]) by s1.gw.fujitsu.co.jp (Postfix) with ESMTP id 0AF37E08001 for ; Tue, 12 Aug 2014 08:55:27 +0900 (JST) Message-ID: <53E957E7.3030503@jp.fujitsu.com> Date: Tue, 12 Aug 2014 08:55:19 +0900 From: Satoru Takeuchi MIME-Version: 1.0 To: Eric Sandeen , "linux-btrfs@vger.kernel.org" Subject: Re: [PATCH 1/3] btrfs-progs: random fixes of btrfs-filesystem documentation References: <53E888C3.70807@jp.fujitsu.com> <53E8F7F0.3060300@redhat.com> <53E8F9E0.3050907@redhat.com> In-Reply-To: <53E8F9E0.3050907@redhat.com> Content-Type: text/plain; charset="ISO-2022-JP" Sender: linux-btrfs-owner@vger.kernel.org List-ID: Hi Eric, (2014/08/12 2:14), Eric Sandeen wrote: > On 8/11/14, 10:05 AM, Eric Sandeen wrote: >> On 8/11/14, 2:11 AM, Satoru Takeuchi wrote: >>> From: Satoru Takeuchi >>> >>> - Simplify and unify the description of both man and usage. >>> - Fix to show -m and -d is not exclusive >>> with "|||". >>> - Add the description about short options for "--mounted" and >>> "--all-devices", "-m" and "-d" respectively. >>> - Move the descriptions of options to "Options" section. >>> >>> Signed-off-by: Satoru Takeuchi >>> >>> --- >>> Documentation/btrfs-filesystem.txt | 22 ++++++++++++++-------- >>> cmds-filesystem.c | 15 ++++++++++----- >>> 2 files changed, 24 insertions(+), 13 deletions(-) >>> >>> diff --git a/Documentation/btrfs-filesystem.txt b/Documentation/btrfs-filesystem.txt >>> index c9c0b00..fe68496 100644 >>> --- a/Documentation/btrfs-filesystem.txt >>> +++ b/Documentation/btrfs-filesystem.txt >>> @@ -20,15 +20,21 @@ SUBCOMMAND >>> *df* [...]:: >>> Show space usage information for a mount point. >>> >>> -*show* [--mounted|--all-devices||||]:: >>> -Show the btrfs filesystem with some additional info. >>> +*show* [-d|-m] [|||]:: >>> +Show the structure of btrfs filesystem(s). >>> + >>> -If no option nor ||| is passed, btrfs shows >>> -information of all the btrfs filesystem both mounted and unmounted. >>> -If '--mounted' is passed, it would probe btrfs kernel to list mounted btrfs >>> -filesystem(s); >>> -If '--all-devices' is passed, all the devices under /dev are scanned; >>> -otherwise the devices list is extracted from the /proc/partitions file. >> >>> +If none of '|||' is passed, btrfs shows >>> +information of all the btrfs filesystems both mounted and unmounted. >> >> that doesn't seem quite correct; >> >> # btrfs filesystem show -m >> >> does not specify '|||' but it only shows >> mounted filesystems, not all filesystems. >> >> As I understand it, the -d and -m options control how the command >> finds devices; the '|||' argument is >> used as a filter for what is found. >> >>> ++ >>> +The show command finds btrfs filesystems by scanning all the devices >>> +in /proc/partitions by default. >> >> I think I would document it something like this: >> >> show [-m|-d] [|||] >> Show the structure of btrfs filesystem(s). >> >> By default, the show command scans all devices found in /proc/partitions. >> If [-d|--all-devices] is specified, all devices found under /dev are scanned. >> If [-m|--mounted] is specified, only mounted (btrfs?) devices are scanned. >> >> By default, the structure of all discovered filesystems is shown. >> If any one of [|||] is specified, only filesystems >> matching that identifier are shown. >> >> (What seems to be missing, though, is why would the user ever choose to use '-d?') > > Incidentally, there is some strange behavior here when looking for multiple filesystems which match. > > Make 2 filesystems w/ the same label: > > [root@bp-05 tmp]# btrfs filesystem label /dev/sdc1 testlabel2 > [root@bp-05 tmp]# btrfs filesystem label /dev/sdc5 testlabel2 > > Show matching filesytems: > > [root@bp-05 tmp]# btrfs filesystem show testlabel2 > Label: 'testlabel2' uuid: 8c6ec835-5628-439b-9749-d92f62573ce8 > Total devices 1 FS bytes used 112.00KiB > devid 1 size 30.00GiB used 2.04GiB path /dev/sdc5 > > Label: 'testlabel2' uuid: a43cd507-02a2-46d2-a754-322cb7bdc346 > Total devices 1 FS bytes used 384.00KiB > devid 1 size 30.00GiB used 2.04GiB path /dev/sdc1 > > Btrfs v3.14.2 > > That works fine, but if one is mounted: > > [root@bp-05 tmp]# mount /dev/sdc1 /mnt/test > > only the mounted filesystem is shown: > > [root@bp-05 tmp]# btrfs filesystem show testlabel2 > Label: 'testlabel2' uuid: a43cd507-02a2-46d2-a754-322cb7bdc346 > Total devices 1 FS bytes used 384.00KiB > devid 1 size 30.00GiB used 2.04GiB path /dev/sdc1 > > Btrfs v3.14.2 > > That's unexpected. > > Mount the other fs, and both are shown again: > > [root@bp-05 tmp]# mount /dev/sdc5 /mnt/scratch > [root@bp-05 tmp]# btrfs filesystem show testlabel2 > Label: 'testlabel2' uuid: a43cd507-02a2-46d2-a754-322cb7bdc346 > Total devices 1 FS bytes used 384.00KiB > devid 1 size 30.00GiB used 2.04GiB path /dev/sdc1 > > Label: 'testlabel2' uuid: 8c6ec835-5628-439b-9749-d92f62573ce8 > Total devices 1 FS bytes used 384.00KiB > devid 1 size 30.00GiB used 2.04GiB path /dev/sdc5 > > Btrfs v3.14.2 I'll dig into it. Thank you for let me know. Satoru > > > -Eric > -- > 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 >