Re: [PATCH] ncpfs: fix rmdir returns Device or resource busy

[Dave Chiluk <chiluk@canonical.com>]

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Can't you just use the patch from my original e-mail?  Anyhow I attached
it an already signed-off patch.

Al Viro Can you integrate it now?

Dave.

On 06/07/2013 01:43 AM, Petr Vandrovec wrote:
> On Wed, Jun 5, 2013 at 1:20 PM, Dave Chiluk <chiluk@canonical.com> wrote:
>> Petr do you still have commit rights to ncpfs?  Can you please commit it
>> to upstream or do I have to get Al to do that?
> 
> Hi,
>   only thing I can do is to add
> 
> Signed-off-by: Petr Vandrovec <petr@vandrovec.name>
> 
> on your patch and forward it to Al.  Unfortunately patch below is
> already whitespace-damaged :-(  So you can either send it to me, and
> I'll resend it to Al, or you can do that directly...
> 
> Petr
> 
>> Dave.
>>
>>
>> On 05/31/2013 05:22 PM, Petr Vandrovec wrote:
>>> Looks OK to me.
>>>
>>> As I said elsewhere, I do not use ncpfs for years so I cannot provide
>>> any sensible maintainership for it anymore :-(
>>>
>>> Petr
>>>
>>> On May 31, 2013 2:40 PM, "Dave Chiluk" <chiluk@canonical.com
>>> <mailto:chiluk@canonical.com>> wrote:
>>>
>>>     Any thoughts on this?  NCPFS seems to be the forgotten, left-behind,
>>>     red-headed stepchild of the fs community.
>>>
>>>     Dave.
>>>
>>>     On 05/28/2013 05:50 PM, Dave Chiluk wrote:
>>>     > 1d2ef5901483004d74947bbf78d5146c24038fe7 caused a regression in
>>>     ncpfs such that
>>>     > directories could no longer be removed.  This was because
>>>     ncp_rmdir checked
>>>     > to see if a dentry could be unhashed before allowing it to be
>>>     removed. Since
>>>     > 1d2ef5901483004d74947bbf78d5146c24038fe7 introduced a change that
>>>     incremented
>>>     > dentry->d_count causing it to always be greater than 1 unhash
>>>     would always
>>>     > fail.  Thus causing the error path in ncp_rmdir to always be
>>>     taken.  Removing
>>>     > this error path is safe as unhashing is still accomplished by
>>>     calls to dput
>>>     > from vfs_rmdir.
>>>     > ---
>>>     >  fs/ncpfs/dir.c |    9 ---------
>>>     >  1 file changed, 9 deletions(-)
>>>     >
>>>     > diff --git a/fs/ncpfs/dir.c b/fs/ncpfs/dir.c
>>>     > index 8163260..6792ce1 100644
>>>     > --- a/fs/ncpfs/dir.c
>>>     > +++ b/fs/ncpfs/dir.c
>>>     > @@ -1029,15 +1029,6 @@ static int ncp_rmdir(struct inode *dir,
>>>     struct dentry *dentry)
>>>     >       DPRINTK("ncp_rmdir: removing %s/%s\n",
>>>     >               dentry->d_parent->d_name.name <http://d_name.name>,
>>>     dentry->d_name.name <http://d_name.name>);
>>>     >
>>>     > -     /*
>>>     > -      * fail with EBUSY if there are still references to this
>>>     > -      * directory.
>>>     > -      */
>>>     > -     dentry_unhash(dentry);
>>>     > -     error = -EBUSY;
>>>     > -     if (!d_unhashed(dentry))
>>>     > -             goto out;
>>>     > -
>>>     >       len = sizeof(__name);
>>>     >       error = ncp_io2vol(server, __name, &len, dentry->d_name.name
>>>     <http://d_name.name>,
>>>     >                          dentry->d_name.len, !ncp_preserve_case(dir));
>>>     >
>>>
>>
> 


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>From 6af7fb5452c6e6edd10316338982ff85ada2cfcf Mon Sep 17 00:00:00 2001
From: Dave Chiluk <chiluk@canonical.com>
Date: Tue, 28 May 2013 16:06:08 -0500
Subject: [PATCH] ncpfs: fix rmdir returns Device or resource busy

1d2ef5901483004d74947bbf78d5146c24038fe7 caused a regression in ncpfs such that
directories could no longer be removed.  This was because ncp_rmdir checked
to see if a dentry could be unhashed before allowing it to be removed. Since
1d2ef5901483004d74947bbf78d5146c24038fe7 introduced a change that incremented
dentry->d_count causing it to always be greater than 1 unhash would always
fail.  Thus causing the error path in ncp_rmdir to always be taken.  Removing
this error path is safe as unhashing is still accomplished by calls to dput
from vfs_rmdir.

Signed-off-by: Dave Chiluk <chiluk@canonical.com>
Signed-off-by: Petr Vandrovec <petr@vandrovec.name>
---
 fs/ncpfs/dir.c |    9 ---------
 1 file changed, 9 deletions(-)

diff --git a/fs/ncpfs/dir.c b/fs/ncpfs/dir.c
index 8163260..6792ce1 100644
--- a/fs/ncpfs/dir.c
+++ b/fs/ncpfs/dir.c
@@ -1029,15 +1029,6 @@ static int ncp_rmdir(struct inode *dir, struct dentry *dentry)
 	DPRINTK("ncp_rmdir: removing %s/%s\n",
 		dentry->d_parent->d_name.name, dentry->d_name.name);
 
-	/*
-	 * fail with EBUSY if there are still references to this
-	 * directory.
-	 */
-	dentry_unhash(dentry);
-	error = -EBUSY;
-	if (!d_unhashed(dentry))
-		goto out;
-
 	len = sizeof(__name);
 	error = ncp_io2vol(server, __name, &len, dentry->d_name.name,
 			   dentry->d_name.len, !ncp_preserve_case(dir));
-- 
1.7.9.5