From: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
To: Chung-Chiang Cheng <shepjeng@gmail.com>
Cc: Chung-Chiang Cheng <cccheng@synology.com>,
linux-fsdevel@vger.kernel.org, kernel@cccheng.net
Subject: Re: [PATCH 2/2] fat: introduce creation time
Date: Wed, 23 Mar 2022 19:57:16 +0900 [thread overview]
Message-ID: <87o81x0wdv.fsf@mail.parknet.co.jp> (raw)
In-Reply-To: <CAHuHWtk1-AdKoa-SBOb=sJAM=32reVzcUQYjrrxvOPYwFZJqXQ@mail.gmail.com> (Chung-Chiang Cheng's message of "Wed, 23 Mar 2022 18:27:43 +0800")
Chung-Chiang Cheng <shepjeng@gmail.com> writes:
> I got your point. Correctly speaking ctime is not really dropped but mixed
> with mtime after my patch. They share the same field on disk. Before that
> ctime is mixed with crtime.
>
> I choose this new behavior because ctime and mtime are similar concepts.
> ctime is the update time for file attributes, and mtime is the one for file
> contents. They are updated together most of the time with few exceptions
> (rename, rmdir, unlink) in the current FAT implementation.
No, a user can change the ctime to arbitrary time, and after the your
patch, the changed ctime only hold on a memory inode. So a user sees
ctime jump backward and forward when a memory inode is expired. (Of
course, this happens just by "cp -a" in real world use case.)
I'm pointing about this introduced new behavior by your patch.
Thanks.
--
OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
next prev parent reply other threads:[~2022-03-23 10:57 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-03-21 9:58 [PATCH 1/2] fat: split fat_truncate_time() into separate functions Chung-Chiang Cheng
2022-03-21 9:58 ` [PATCH 2/2] fat: introduce creation time Chung-Chiang Cheng
2022-03-22 7:33 ` OGAWA Hirofumi
2022-03-23 2:14 ` Chung-Chiang Cheng
2022-03-23 6:57 ` OGAWA Hirofumi
2022-03-23 10:27 ` Chung-Chiang Cheng
2022-03-23 10:57 ` OGAWA Hirofumi [this message]
2022-03-25 7:38 ` Chung-Chiang Cheng
2022-03-25 10:36 ` OGAWA Hirofumi
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