linux-fsdevel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: bfields@fieldses.org (J. Bruce Fields)
To: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
	linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH 07/15] reconnect_one(): use lookup_one_len_unlocked()
Date: Mon, 18 Apr 2016 15:23:51 -0400	[thread overview]
Message-ID: <20160418192351.GC3193@fieldses.org> (raw)
In-Reply-To: <1460768127-31822-7-git-send-email-viro@ZenIV.linux.org.uk>

On Sat, Apr 16, 2016 at 01:55:19AM +0100, Al Viro wrote:
> From: Al Viro <viro@zeniv.linux.org.uk>
> 
> ... and explain the non-obvious logics in case when lookup yields
> a different dentry.

ACK to this independent of the rest of the series, my only minor gripe
is that the point made in this new comment is also made at
out_reconnected: and at the head of reconnect_one().  And would also
apply at the other "goto out_reconnected".  My preference is to leave
things as they are, but if you found it easy to overlook maybe just
something like:

 -		goto out_reconnected;
 +		goto out_reconnected; /* see comment there*/

would be helpful.  And/or improving the final comment.

--b.

> 
> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
> ---
>  fs/exportfs/expfs.c | 10 +++++++---
>  1 file changed, 7 insertions(+), 3 deletions(-)
> 
> diff --git a/fs/exportfs/expfs.c b/fs/exportfs/expfs.c
> index c46f1a1..402c5ca 100644
> --- a/fs/exportfs/expfs.c
> +++ b/fs/exportfs/expfs.c
> @@ -143,14 +143,18 @@ static struct dentry *reconnect_one(struct vfsmount *mnt,
>  	if (err)
>  		goto out_err;
>  	dprintk("%s: found name: %s\n", __func__, nbuf);
> -	inode_lock(parent->d_inode);
> -	tmp = lookup_one_len(nbuf, parent, strlen(nbuf));
> -	inode_unlock(parent->d_inode);
> +	tmp = lookup_one_len_unlocked(nbuf, parent, strlen(nbuf));
>  	if (IS_ERR(tmp)) {
>  		dprintk("%s: lookup failed: %d\n", __func__, PTR_ERR(tmp));
>  		goto out_err;
>  	}
>  	if (tmp != dentry) {
> +		/*
> +		 * Somebody has renamed it since exportfs_get_name();
> +		 * great, since it could've only been renamed if it
> +		 * got looked up and thus connected, and it would
> +		 * remain connected afterwards.  We are done.
> +		 */
>  		dput(tmp);
>  		goto out_reconnected;
>  	}
> -- 
> 2.8.0.rc3
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html

  reply	other threads:[~2016-04-18 19:23 UTC|newest]

Thread overview: 24+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-04-16  0:52 [PATCHSET][RFC][CFT] parallel lookups Al Viro
2016-04-16  0:55 ` [PATCH 01/15] security_d_instantiate(): move to the point prior to attaching dentry to inode Al Viro
2016-04-16  0:55 ` [PATCH 02/15] kernfs: use lookup_one_len_unlocked() Al Viro
2016-04-16  0:55 ` [PATCH 03/15] configfs_detach_prep(): make sure that wait_mutex won't go away Al Viro
2016-04-16  0:55 ` [PATCH 04/15] ocfs2: don't open-code inode_lock/inode_unlock Al Viro
2016-04-16  0:55 ` [PATCH 05/15] orangefs: " Al Viro
2016-04-16  0:55 ` [PATCH 06/15] reiserfs: open-code reiserfs_mutex_lock_safe() in reiserfs_unpack() Al Viro
2016-04-16  0:55 ` [PATCH 07/15] reconnect_one(): use lookup_one_len_unlocked() Al Viro
2016-04-18 19:23   ` J. Bruce Fields [this message]
2016-04-16  0:55 ` [PATCH 08/15] ovl_lookup_real(): " Al Viro
2016-04-16  0:55 ` [PATCH 09/15] lookup_slow(): bugger off on IS_DEADDIR() from the very beginning Al Viro
2016-04-16  0:55 ` [PATCH 10/15] __d_add(): don't drop/regain ->d_lock Al Viro
2016-04-24 18:09   ` Jeff Layton
2016-04-24 19:21     ` Al Viro
2016-04-16  0:55 ` [PATCH 11/15] beginning of transition to parallel lookups - marking in-lookup dentries Al Viro
2016-04-16  0:55 ` [PATCH 12/15] parallel lookups machinery, part 2 Al Viro
2016-04-16  0:55 ` [PATCH 13/15] parallel lookups machinery, part 3 Al Viro
2016-04-18 20:45   ` J. Bruce Fields
2016-04-16  0:55 ` [PATCH 14/15] parallel lookups machinery, part 4 (and last) Al Viro
2016-04-16  0:55 ` [PATCH 15/15] parallel lookups: actual switch to rwsem Al Viro
2016-04-16  3:02   ` Andreas Dilger
2016-04-16  3:31     ` Al Viro
2016-04-16  3:02 ` [PATCHSET][RFC][CFT] parallel lookups Andreas Dilger
2016-04-16  3:27   ` Al Viro

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20160418192351.GC3193@fieldses.org \
    --to=bfields@fieldses.org \
    --cc=linux-fsdevel@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=torvalds@linux-foundation.org \
    --cc=viro@ZenIV.linux.org.uk \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).