From: "J. Bruce Fields" <bfields@fieldses.org>
To: "Darrick J. Wong" <darrick.wong@oracle.com>
Cc: William Koh <kkc6196@fb.com>, Andreas Dilger <adilger@dilger.ca>,
"Theodore Ts'o" <tytso@mit.edu>,
linux-ext4 <linux-ext4@vger.kernel.org>,
lkml <linux-kernel@vger.kernel.org>,
Kernel Team <Kernel-team@fb.com>,
linux-fsdevel <linux-fsdevel@vger.kernel.org>,
Trond Myklebust <trond.myklebust@primarydata.com>,
xfs <linux-xfs@vger.kernel.org>
Subject: Re: [PATCH] fs: ext4: inode->i_generation not assigned 0.
Date: Thu, 29 Jun 2017 14:30:53 -0400 [thread overview]
Message-ID: <20170629183053.GA4178@fieldses.org> (raw)
In-Reply-To: <20170629172528.GA5869@birch.djwong.org>
On Thu, Jun 29, 2017 at 10:25:28AM -0700, Darrick J. Wong wrote:
> Was there ever a version of NFS (or more generally callers of the
> exportfs code) that couldn't deal with i_generation in the file handle,
> and therefore we invented this generation hack to work around the loss
> of the generation information?
>
> There's a comment in xfs_fs_encode_fh about not supporting 64bit inodes
> with subtree_check (which seems to require one ino/gen pair for the file
> and a second pair for the file's parent) on NFSv2 because v2 doesn't
> provide enough space for all the file handle information, but that's the
> furthest I got with lazy-mining the git history. :)
There's a comment in fs/ext4/super.c:ext4_nfs_get_inode
* Currently we don't know the generation for parent directory, so
* a generation of 0 means "accept any"
But I don't see that used.
It was used once upon a time; I see it actually used in old 2.5 code in
nfsd_get_dentry. Hm.
--b.
next prev parent reply other threads:[~2017-06-29 18:31 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-06-28 22:06 [PATCH] fs: ext4: inode->i_generation not assigned 0 Kyungchan Koh
2017-06-29 0:48 ` Darrick J. Wong
2017-06-29 0:58 ` William Koh
2017-06-29 2:32 ` Andreas Dilger
2017-06-29 4:37 ` William Koh
2017-06-29 4:59 ` Darrick J. Wong
2017-06-29 14:28 ` William Koh
2017-06-29 14:35 ` J. Bruce Fields
2017-06-29 17:25 ` Darrick J. Wong
2017-06-29 18:30 ` J. Bruce Fields [this message]
2017-06-29 18:50 ` J. Bruce Fields
2017-07-04 4:04 ` Darrick J. Wong
2017-07-05 1:15 ` J. Bruce Fields
2017-07-05 19:19 ` Darrick J. Wong
2017-07-05 20:27 ` Theodore Ts'o
2017-07-07 10:51 ` Jeff Layton
2017-07-07 15:51 ` Theodore Ts'o
2017-07-07 16:13 ` Jeff Layton
2017-07-07 16:47 ` J. Bruce Fields
2017-07-05 20:49 ` J. Bruce Fields
2017-07-06 1:08 ` NeilBrown
2017-07-06 2:39 ` J. Bruce Fields
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