[patch] unexport __mntput()

[patch] unexport __mntput()

[Coywolf Qi Hunt]

Hello,

Unexport __mntput() was talked about two months ago. http://lkml.org/lkml/2005/6/9/69
Modules should not call __mntput() directly. If autofs or nfsd does that, it's
 being wrong.

		Coywolf


Signed-off-by: Coywolf Qi Hunt <coywolf@sosdg.org>
--- 2.6.13-rc6/fs/namespace.c~unexport-__mntput	2005-08-12 08:21:22.000000000 -0500
+++ 2.6.13-rc6/fs/namespace.c	2005-08-14 20:32:01.000000000 -0500
@@ -180,8 +180,6 @@
 	deactivate_super(sb);
 }
 
-EXPORT_SYMBOL(__mntput);
-
 /* iterator */
 static void *m_start(struct seq_file *m, loff_t *pos)
 {

Re: [patch] unexport __mntput()

[Mike Waychison]

Coywolf Qi Hunt wrote:
> Hello,
> 
> Unexport __mntput() was talked about two months ago. http://lkml.org/lkml/2005/6/9/69
> Modules should not call __mntput() directly. If autofs or nfsd does that, it's
>  being wrong.

I think you missed the point in the last discussion.  __mntput is called 
from mntput(), which autofs and nfsd call.  Their use is correct given 
what they do:

Autofs 3 and 4 use it for walking the vfsmount tree and determining 
if/when a mountpoint is ready to expire.

Nfsd uses it to serve up nfs exports that don't cross mountpoints (or 
do, if "crossmnt" is specified in /etc/exports.

Thanks,

Mike Waychison

> 
> 		Coywolf
> 
> 
> Signed-off-by: Coywolf Qi Hunt <coywolf@sosdg.org>
> --- 2.6.13-rc6/fs/namespace.c~unexport-__mntput	2005-08-12 08:21:22.000000000 -0500
> +++ 2.6.13-rc6/fs/namespace.c	2005-08-14 20:32:01.000000000 -0500
> @@ -180,8 +180,6 @@
>  	deactivate_super(sb);
>  }
>  
> -EXPORT_SYMBOL(__mntput);
> -
>  /* iterator */
>  static void *m_start(struct seq_file *m, loff_t *pos)
>  {

Re: [patch] unexport __mntput()

[Coywolf Qi Hunt]

On 8/15/05, Mike Waychison <mikew@google.com> wrote:
> Coywolf Qi Hunt wrote:
> > Hello,
> >
> > Unexport __mntput() was talked about two months ago. http://lkml.org/lkml/2005/6/9/69
> > Modules should not call __mntput() directly. If autofs or nfsd does that, it's
> >  being wrong.
> 
> I think you missed the point in the last discussion.  __mntput is called

Yes, indeed.

> from mntput(), which autofs and nfsd call.  Their use is correct given
> what they do:
> 
> Autofs 3 and 4 use it for walking the vfsmount tree and determining
> if/when a mountpoint is ready to expire.
> 
> Nfsd uses it to serve up nfs exports that don't cross mountpoints (or
> do, if "crossmnt" is specified in /etc/exports.

And more than above, there's more stuff depend on it, af_unix, ipc
message queues, etc.

Thanks for your help.
-- 
Coywolf Qi Hunt
http://ahbl.org/~coywolf/

Re: [patch] unexport __mntput()

[Jan Engelhardt]

> Nfsd uses it to serve up nfs exports that don't cross mountpoints (or do, if
> "crossmnt" is specified in /etc/exports.

Is not this called nohide?



Jan Engelhardt
-- 

Re: [patch] unexport __mntput()

[Mike Waychison]

Jan Engelhardt wrote:
>>Nfsd uses it to serve up nfs exports that don't cross mountpoints (or do, if
>>"crossmnt" is specified in /etc/exports.
> 
> 
> Is not this called nohide?
> 
> 

On the command line it's a synonym, but the nfs-utils uses 
NFSEXP_CROSSMOUNT to tell the kernel.

Mike Waychison