[PATCH] Push BKL into ->permission() calls

[PATCH] Push BKL into ->permission() calls

[Paul Menage]

This patch (against 2.5.22) removes the BKL from around the call 
to i_op->permission() in fs/namei.c, and pushes the BKL into those 
filesystems that have permission() methods that require it:

fs/nfs/dir.c:nfs_permission():  Take BKL if we need to do RPC

fs/coda/dir.c:coda_permission(): Take BKL if mask != 0

fs/coda/pioctl.c:coda_ioctl_permission(): BKL not needed

net/wanrouter/wanproc.c:router_proc_perms(): BKL not needed 

fs/intermezzo/dir.c:presto_permission(): Always take BKL (and avoid
abuse of inode method table) (but it still doesn't compile due to 
earlier breakage)

fs/proc/base.c:proc_permission(): BKL not needed

fs/smbfs/file.c:smb_file_permission(): BKL not needed

kernel/sysctl.c:proc_sys_permission(): BKL not needed

Out-of-tree filesystems that have their own permission() method will 
need updating if they're relying on the BKL.

All feedback welcome.

Paul

diff -X /mnt/elbrus/home/pmenage/dontdiff -Naur linux-2.5.22/Documentation/filesystems/Locking linux-2.5.22-permission/Documentation/filesystems/Locking
--- linux-2.5.22/Documentation/filesystems/Locking	Sat Jun  8 22:28:48 2002
+++ linux-2.5.22-permission/Documentation/filesystems/Locking	Mon Jun 17 16:34:09 2002
@@ -50,27 +50,27 @@
 	int (*removexattr) (struct dentry *, const char *);
 
 locking rules:
-	all may block
-		BKL	i_sem(inode)
-lookup:		no	yes
-create:		no	yes
-link:		no	yes (both)
-mknod:		no	yes
-symlink:	no	yes
-mkdir:		no	yes
-unlink:		no	yes (both)
-rmdir:		no	yes (both)	(see below)
-rename:		no	yes (all)	(see below)
-readlink:	no	no
-follow_link:	no	no
-truncate:	no	yes		(see below)
-setattr:	no	yes
-permission:	yes	no
-getattr:	no	no
-setxattr:	no	yes
-getxattr:	no	yes
-listxattr:	no	yes
-removexattr:	no	yes
+	all may block, none have BKL
+		i_sem(inode)
+lookup:		yes
+create:		yes
+link:		yes (both)
+mknod:		yes
+symlink:	yes
+mkdir:		yes
+unlink:		yes (both)
+rmdir:		yes (both)	(see below)
+rename:		yes (all)	(see below)
+readlink:	no
+follow_link:	no
+truncate:	yes		(see below)
+setattr:	yes
+permission:	no
+getattr:	no
+setxattr:	yes
+getxattr:	yes
+listxattr:	yes
+removexattr:	yes
 	Additionally, ->rmdir(), ->unlink() and ->rename() have ->i_sem on
 victim.
 	cross-directory ->rename() has (per-superblock) ->s_vfs_rename_sem.
diff -X /mnt/elbrus/home/pmenage/dontdiff -Naur linux-2.5.22/fs/coda/dir.c linux-2.5.22-permission/fs/coda/dir.c
--- linux-2.5.22/fs/coda/dir.c	Sat Jun  8 22:27:26 2002
+++ linux-2.5.22-permission/fs/coda/dir.c	Mon Jun 17 16:34:09 2002
@@ -147,21 +147,26 @@
 
 int coda_permission(struct inode *inode, int mask)
 {
-        int error;
+        int error = 0;
  
 	if (!mask)
 		return 0; 
 
+	lock_kernel();
+
 	coda_vfs_stat.permission++;
 
 	if (coda_cache_check(inode, mask))
-		return 0; 
+		goto out; 
 
         error = venus_access(inode->i_sb, coda_i2f(inode), mask);
     
 	if (!error)
 		coda_cache_enter(inode, mask);
 
+ out:
+	unlock_kernel();
+
         return error; 
 }
 
diff -X /mnt/elbrus/home/pmenage/dontdiff -Naur linux-2.5.22/fs/intermezzo/dir.c linux-2.5.22-permission/fs/intermezzo/dir.c
--- linux-2.5.22/fs/intermezzo/dir.c	Sat Jun  8 22:28:16 2002
+++ linux-2.5.22-permission/fs/intermezzo/dir.c	Mon Jun 17 16:34:09 2002
@@ -785,13 +785,15 @@
 {
         unsigned short mode = inode->i_mode;
         struct presto_cache *cache;
-        int rc;
+        int rc = 0;
 
+	lock_kernel();
         ENTRY;
+
         if ( presto_can_ilookup() && !(mask & S_IWOTH)) {
                 CDEBUG(D_CACHE, "ilookup on %ld OK\n", inode->i_ino);
-                EXIT;
-                return 0;
+		EXIT;
+		goto out;
         }
 
         cache = presto_get_cache(inode);
@@ -803,25 +805,22 @@
 
                 if ( S_ISREG(mode) && fiops && fiops->permission ) {
                         EXIT;
-                        return fiops->permission(inode, mask);
+                        rc = fiops->permission(inode, mask);
+			goto out;
                 }
                 if ( S_ISDIR(mode) && diops && diops->permission ) {
                         EXIT;
-                        return diops->permission(inode, mask);
+                        rc = diops->permission(inode, mask);
+			goto out;
                 }
         }
 
-        /* The cache filesystem doesn't have its own permission function,
-         * but we don't want to duplicate the VFS code here.  In order
-         * to avoid looping from permission calling this function again,
-         * we temporarily override the permission operation while we call
-         * the VFS permission function.
-         */
-        inode->i_op->permission = NULL;
-        rc = permission(inode, mask);
-        inode->i_op->permission = &presto_permission;
+        rc = vfs_permission(inode, mask);
 
         EXIT;
+
+ out:
+	unlock_kernel();
         return rc;
 }
 
diff -X /mnt/elbrus/home/pmenage/dontdiff -Naur linux-2.5.22/fs/namei.c linux-2.5.22-permission/fs/namei.c
--- linux-2.5.22/fs/namei.c	Sat Jun  8 22:28:50 2002
+++ linux-2.5.22-permission/fs/namei.c	Mon Jun 17 16:34:09 2002
@@ -204,13 +204,8 @@
 
 int permission(struct inode * inode,int mask)
 {
-	if (inode->i_op && inode->i_op->permission) {
-		int retval;
-		lock_kernel();
-		retval = inode->i_op->permission(inode, mask);
-		unlock_kernel();
-		return retval;
-	}
+	if (inode->i_op && inode->i_op->permission)
+		return inode->i_op->permission(inode, mask);
 	return vfs_permission(inode, mask);
 }
 
diff -X /mnt/elbrus/home/pmenage/dontdiff -Naur linux-2.5.22/fs/nfs/dir.c linux-2.5.22-permission/fs/nfs/dir.c
--- linux-2.5.22/fs/nfs/dir.c	Sat Jun  8 22:29:55 2002
+++ linux-2.5.22-permission/fs/nfs/dir.c	Mon Jun 17 16:34:09 2002
@@ -1123,6 +1123,8 @@
 	    && error != -EACCES)
 		goto out;
 
+	lock_kernel();
+
 	error = NFS_PROTO(inode)->access(inode, mask, 0);
 
 	if (error == -EACCES && NFS_CLIENT(inode)->cl_droppriv &&
@@ -1130,6 +1132,8 @@
 	    (current->fsuid != current->uid || current->fsgid != current->gid))
 		error = NFS_PROTO(inode)->access(inode, mask, 1);
 
+	unlock_kernel();
+
  out:
 	return error;
 }

Re: [PATCH] Push BKL into ->permission() calls

[Andreas Dilger]

On Jun 18, 2002  00:27 -0700, Paul Menage wrote:
> This patch (against 2.5.22) removes the BKL from around the call 
> to i_op->permission() in fs/namei.c, and pushes the BKL into those 
> filesystems that have permission() methods that require it:
>
> Out-of-tree filesystems that have their own permission() method will 
> need updating if they're relying on the BKL.

Please update Documentation/filesystems/porting with this info as part
of your patch.

Cheers, Andreas
--
Andreas Dilger
http://www-mddsp.enel.ucalgary.ca/People/adilger/
http://sourceforge.net/projects/ext2resize/

Re: [PATCH] Push BKL into ->permission() calls

[Paul Menage]

>On Jun 18, 2002  00:27 -0700, Paul Menage wrote:
>Please update Documentation/filesystems/porting with this info as part
>of your patch.
>

OK. Documentation/filesystems/porting is included this time.

==============================================================

This patch (against 2.5.22) removes the BKL from around the call 
to i_op->permission() in fs/namei.c, and pushes the BKL into those 
filesystems that have permission() methods that require it:

fs/nfs/dir.c:nfs_permission():  Take BKL if we need to do RPC

fs/coda/dir.c:coda_permission(): Take BKL if mask != 0

fs/coda/pioctl.c:coda_ioctl_permission(): BKL not needed

net/wanrouter/wanproc.c:router_proc_perms(): BKL not needed 

fs/intermezzo/dir.c:presto_permission(): Always take BKL (and avoid
abuse of inode method table) (but it still doesn't compile due to 
earlier breakage)

fs/proc/base.c:proc_permission(): BKL not needed

fs/smbfs/file.c:smb_file_permission(): BKL not needed

kernel/sysctl.c:proc_sys_permission(): BKL not needed

Out-of-tree filesystems that have their own permission() method will 
need updating if they're relying on the BKL.

All feedback welcome.

Paul

diff -X /mnt/elbrus/home/pmenage/dontdiff -Naur linux-2.5.22/Documentation/filesystems/Locking linux-2.5.22-permission/Documentation/filesystems/Locking
--- linux-2.5.22/Documentation/filesystems/Locking	Sat Jun  8 22:28:48 2002
+++ linux-2.5.22-permission/Documentation/filesystems/Locking	Mon Jun 17 16:34:09 2002
@@ -50,27 +50,27 @@
 	int (*removexattr) (struct dentry *, const char *);
 
 locking rules:
-	all may block
-		BKL	i_sem(inode)
-lookup:		no	yes
-create:		no	yes
-link:		no	yes (both)
-mknod:		no	yes
-symlink:	no	yes
-mkdir:		no	yes
-unlink:		no	yes (both)
-rmdir:		no	yes (both)	(see below)
-rename:		no	yes (all)	(see below)
-readlink:	no	no
-follow_link:	no	no
-truncate:	no	yes		(see below)
-setattr:	no	yes
-permission:	yes	no
-getattr:	no	no
-setxattr:	no	yes
-getxattr:	no	yes
-listxattr:	no	yes
-removexattr:	no	yes
+	all may block, none have BKL
+		i_sem(inode)
+lookup:		yes
+create:		yes
+link:		yes (both)
+mknod:		yes
+symlink:	yes
+mkdir:		yes
+unlink:		yes (both)
+rmdir:		yes (both)	(see below)
+rename:		yes (all)	(see below)
+readlink:	no
+follow_link:	no
+truncate:	yes		(see below)
+setattr:	yes
+permission:	no
+getattr:	no
+setxattr:	yes
+getxattr:	yes
+listxattr:	yes
+removexattr:	yes
 	Additionally, ->rmdir(), ->unlink() and ->rename() have ->i_sem on
 victim.
 	cross-directory ->rename() has (per-superblock) ->s_vfs_rename_sem.
diff -X /mnt/elbrus/home/pmenage/dontdiff -Naur linux-2.5.22/fs/coda/dir.c linux-2.5.22-permission/fs/coda/dir.c
--- linux-2.5.22/fs/coda/dir.c	Sat Jun  8 22:27:26 2002
+++ linux-2.5.22-permission/fs/coda/dir.c	Mon Jun 17 16:34:09 2002
@@ -147,21 +147,26 @@
 
 int coda_permission(struct inode *inode, int mask)
 {
-        int error;
+        int error = 0;
  
 	if (!mask)
 		return 0; 
 
+	lock_kernel();
+
 	coda_vfs_stat.permission++;
 
 	if (coda_cache_check(inode, mask))
-		return 0; 
+		goto out; 
 
         error = venus_access(inode->i_sb, coda_i2f(inode), mask);
     
 	if (!error)
 		coda_cache_enter(inode, mask);
 
+ out:
+	unlock_kernel();
+
         return error; 
 }
 
diff -X /mnt/elbrus/home/pmenage/dontdiff -Naur linux-2.5.22/fs/intermezzo/dir.c linux-2.5.22-permission/fs/intermezzo/dir.c
--- linux-2.5.22/fs/intermezzo/dir.c	Sat Jun  8 22:28:16 2002
+++ linux-2.5.22-permission/fs/intermezzo/dir.c	Mon Jun 17 16:34:09 2002
@@ -785,13 +785,15 @@
 {
         unsigned short mode = inode->i_mode;
         struct presto_cache *cache;
-        int rc;
+        int rc = 0;
 
+	lock_kernel();
         ENTRY;
+
         if ( presto_can_ilookup() && !(mask & S_IWOTH)) {
                 CDEBUG(D_CACHE, "ilookup on %ld OK\n", inode->i_ino);
-                EXIT;
-                return 0;
+		EXIT;
+		goto out;
         }
 
         cache = presto_get_cache(inode);
@@ -803,25 +805,22 @@
 
                 if ( S_ISREG(mode) && fiops && fiops->permission ) {
                         EXIT;
-                        return fiops->permission(inode, mask);
+                        rc = fiops->permission(inode, mask);
+			goto out;
                 }
                 if ( S_ISDIR(mode) && diops && diops->permission ) {
                         EXIT;
-                        return diops->permission(inode, mask);
+                        rc = diops->permission(inode, mask);
+			goto out;
                 }
         }
 
-        /* The cache filesystem doesn't have its own permission function,
-         * but we don't want to duplicate the VFS code here.  In order
-         * to avoid looping from permission calling this function again,
-         * we temporarily override the permission operation while we call
-         * the VFS permission function.
-         */
-        inode->i_op->permission = NULL;
-        rc = permission(inode, mask);
-        inode->i_op->permission = &presto_permission;
+        rc = vfs_permission(inode, mask);
 
         EXIT;
+
+ out:
+	unlock_kernel();
         return rc;
 }
 
diff -X /mnt/elbrus/home/pmenage/dontdiff -Naur linux-2.5.22/fs/namei.c linux-2.5.22-permission/fs/namei.c
--- linux-2.5.22/fs/namei.c	Sat Jun  8 22:28:50 2002
+++ linux-2.5.22-permission/fs/namei.c	Mon Jun 17 16:34:09 2002
@@ -204,13 +204,8 @@
 
 int permission(struct inode * inode,int mask)
 {
-	if (inode->i_op && inode->i_op->permission) {
-		int retval;
-		lock_kernel();
-		retval = inode->i_op->permission(inode, mask);
-		unlock_kernel();
-		return retval;
-	}
+	if (inode->i_op && inode->i_op->permission)
+		return inode->i_op->permission(inode, mask);
 	return vfs_permission(inode, mask);
 }
 
diff -X /mnt/elbrus/home/pmenage/dontdiff -Naur linux-2.5.22/fs/nfs/dir.c linux-2.5.22-permission/fs/nfs/dir.c
--- linux-2.5.22/fs/nfs/dir.c	Sat Jun  8 22:29:55 2002
+++ linux-2.5.22-permission/fs/nfs/dir.c	Mon Jun 17 16:34:09 2002
@@ -1123,6 +1123,8 @@
 	    && error != -EACCES)
 		goto out;
 
+	lock_kernel();
+
 	error = NFS_PROTO(inode)->access(inode, mask, 0);
 
 	if (error == -EACCES && NFS_CLIENT(inode)->cl_droppriv &&
@@ -1130,6 +1132,8 @@
 	    (current->fsuid != current->uid || current->fsgid != current->gid))
 		error = NFS_PROTO(inode)->access(inode, mask, 1);
 
+	unlock_kernel();
+
  out:
 	return error;
 }
--- linux-2.5.22/Documentation/filesystems/porting	Mon Jun 17 16:24:54 2002
+++ linux-2.5.22-permission/Documentation/filesystems/porting	Tue Jun 18 01:16:07 2002
@@ -81,9 +81,9 @@
 [mandatory]
 
 ->lookup(), ->truncate(), ->create(), ->unlink(), ->mknod(), ->mkdir(),
-->rmdir(), ->link(), ->lseek(), ->symlink(), ->rename() and ->readdir() 
-are called without BKL now.  Grab it on the entry, drop upon return - that 
-will guarantee the same locking you used to have.  If your method or its
+->rmdir(), ->link(), ->lseek(), ->symlink(), ->rename(), ->permission()
+and ->readdir() are called without BKL now.  Grab it on entry, drop upon return
+- that will guarantee the same locking you used to have.  If your method or its
 parts do not need BKL - better yet, now you can shift lock_kernel() and
 unlock_kernel() so that they would protect exactly what needs to be
 protected.

2.5.22 problems with compile.h

[Hans E. Kristiansen]

I really need some help with compiling version 2.5.22

>From a clean install, I can compile, but I get an error with compile.h (Do
not know how to make compile.h). If I compile again, I get a working kernel
(bzImage), "depmod -ae -F xx " works like a charm. But, when I reboot with
the new kernel, I can not load any modules. None, they all have symbol
problems.

I use grub for loading, and I have verified that I have the correct
System.map

My last kernel is 2.5.19, which works like a charm ( well... ).

To compile a kernel, I use "make dep clean bzImage modules modules_install",
except for the first compile after an upgrade where I run "make oldconfig"
first.

Thanks,
Hans E.

Re: 2.5.22 problems with compile.h

[Martin Diehl]

On Tue, 18 Jun 2002, Hans E. Kristiansen wrote:

> I really need some help with compiling version 2.5.22
> 
> >From a clean install, I can compile, but I get an error with compile.h (Do
> not know how to make compile.h). If I compile again, I get a working kernel

same here - see below.

> (bzImage), "depmod -ae -F xx " works like a charm. But, when I reboot with
> the new kernel, I can not load any modules. None, they all have symbol
> problems.

There are two patches from Kai Germaschewski in the "2.5.22 broke
modversions" thread which solved this issue for me.

> To compile a kernel, I use "make dep clean bzImage modules modules_install",

replacing this by separate "make dep; make clean; make bzImage; make
modules; make modules_install" invokations solved the compile.h problem
for me.

HTH
Martin

Re: 2.5.22 problems with compile.h

[Kai Germaschewski]

On Tue, 18 Jun 2002, Hans E. Kristiansen wrote:

> >From a clean install, I can compile, but I get an error with compile.h (Do
> not know how to make compile.h). If I compile again, I get a working kernel
> (bzImage), "depmod -ae -F xx " works like a charm. But, when I reboot with
> the new kernel, I can not load any modules. None, they all have symbol
> problems.

Seems that I screwed up that version a bit ;( 

For now, don't use something like "make dep clean bzImage", but rather
"make clean; make dep bzImage" - it'll work again in the next release,
though.

Modversions also have bugs, though I can't see how they lead to the effect 
you describe. Anyway, try changing CONFIG_MODVERSIONS to off for now,
again, it should work again in the next release.

Let me know of further problems ;)

--Kai

Re: 2.5.22 problems with compile.h

[Hans E. Kristiansen]

I applied your patch which was included in an earlier email on the advice
from Mr. Martin Deal, and it works! Can't ask for more. At last I can go
back to my userland programming.

Perhaps the real problem is that Linus released 2.5.22 on a Monday :)

TTFN,
Hans E.

----- Original Message -----
From: "Kai Germaschewski" <kai@tp1.ruhr-uni-bochum.de>
To: "Hans E. Kristiansen" <hans@tropic.net>
Cc: <linux-kernel@vger.kernel.org>
Sent: Tuesday, June 18, 2002 22:36
Subject: Re: 2.5.22 problems with compile.h


> On Tue, 18 Jun 2002, Hans E. Kristiansen wrote:
>
> > >From a clean install, I can compile, but I get an error with compile.h
(Do
> > not know how to make compile.h). If I compile again, I get a working
kernel
> > (bzImage), "depmod -ae -F xx " works like a charm. But, when I reboot
with

--- snip ----

[PATCH] Push BKL into ->permission() calls

[Paul Menage]

The patch below (against 2.5.21) removes the BKL from around the call 
to i_op->permission() in fs/namei.c, and pushes the BKL into those 
filesystems that have permission() methods that require it:

fs/nfs/dir.c:nfs_permission():  Take BKL if we need to do RPC

fs/coda/dir.c:coda_permission(): Take BKL if mask != 0

fs/coda/pioctl.c:coda_ioctl_permission(): BKL not needed

net/wanrouter/wanproc.c:router_proc_perms(): BKL not needed 

fs/intermezzo/dir.c:presto_permission(): Always take BKL (and avoid
abuse of inode method table)

fs/proc/base.c:proc_permission(): BKL not needed

fs/smbfs/file.c:smb_file_permission(): BKL not needed

kernel/sysctl.c:proc_sys_permission(): BKL not needed

Out-of-tree filesystems that have their own permission() method will 
need updating if they're relying on the BKL.

Al, please forward this patch to Linus if you're happy with it.

Paul

diff -aur -X /mnt/elbrus/home/pmenage/dontdiff linux-2.5.21/Documentation/filesystems/Locking linux-2.5.21-permission/Documentation/filesystems/Locking
--- linux-2.5.21/Documentation/filesystems/Locking	Sat Jun  8 22:28:48 2002
+++ linux-2.5.21-permission/Documentation/filesystems/Locking	Sun Jun  9 20:54:51 2002
@@ -50,27 +50,27 @@
 	int (*removexattr) (struct dentry *, const char *);
 
 locking rules:
-	all may block
-		BKL	i_sem(inode)
-lookup:		no	yes
-create:		no	yes
-link:		no	yes (both)
-mknod:		no	yes
-symlink:	no	yes
-mkdir:		no	yes
-unlink:		no	yes (both)
-rmdir:		no	yes (both)	(see below)
-rename:		no	yes (all)	(see below)
-readlink:	no	no
-follow_link:	no	no
-truncate:	no	yes		(see below)
-setattr:	no	yes
-permission:	yes	no
-getattr:	no	no
-setxattr:	no	yes
-getxattr:	no	yes
-listxattr:	no	yes
-removexattr:	no	yes
+	all may block, none have BKL
+		i_sem(inode)
+lookup:		yes
+create:		yes
+link:		yes (both)
+mknod:		yes
+symlink:	yes
+mkdir:		yes
+unlink:		yes (both)
+rmdir:		yes (both)	(see below)
+rename:		yes (all)	(see below)
+readlink:	no
+follow_link:	no
+truncate:	yes		(see below)
+setattr:	yes
+permission:	no
+getattr:	no
+setxattr:	yes
+getxattr:	yes
+listxattr:	yes
+removexattr:	yes
 	Additionally, ->rmdir(), ->unlink() and ->rename() have ->i_sem on
 victim.
 	cross-directory ->rename() has (per-superblock) ->s_vfs_rename_sem.
diff -aur -X /mnt/elbrus/home/pmenage/dontdiff linux-2.5.21/fs/coda/dir.c linux-2.5.21-permission/fs/coda/dir.c
--- linux-2.5.21/fs/coda/dir.c	Sat Jun  8 22:27:26 2002
+++ linux-2.5.21-permission/fs/coda/dir.c	Sun Jun  9 20:31:24 2002
@@ -147,21 +147,26 @@
 
 int coda_permission(struct inode *inode, int mask)
 {
-        int error;
+        int error = 0;
  
 	if (!mask)
 		return 0; 
 
+	lock_kernel();
+
 	coda_vfs_stat.permission++;
 
 	if (coda_cache_check(inode, mask))
-		return 0; 
+		goto out; 
 
         error = venus_access(inode->i_sb, coda_i2f(inode), mask);
     
 	if (!error)
 		coda_cache_enter(inode, mask);
 
+ out:
+	unlock_kernel();
+
         return error; 
 }
 
diff -aur -X /mnt/elbrus/home/pmenage/dontdiff linux-2.5.21/fs/intermezzo/dir.c linux-2.5.21-permission/fs/intermezzo/dir.c
--- linux-2.5.21/fs/intermezzo/dir.c	Sat Jun  8 22:28:16 2002
+++ linux-2.5.21-permission/fs/intermezzo/dir.c	Sun Jun  9 20:57:38 2002
@@ -785,13 +785,15 @@
 {
         unsigned short mode = inode->i_mode;
         struct presto_cache *cache;
-        int rc;
+        int rc = 0;
 
+	lock_kernel();
         ENTRY;
+
         if ( presto_can_ilookup() && !(mask & S_IWOTH)) {
                 CDEBUG(D_CACHE, "ilookup on %ld OK\n", inode->i_ino);
-                EXIT;
-                return 0;
+		EXIT;
+		goto out;
         }
 
         cache = presto_get_cache(inode);
@@ -803,25 +805,22 @@
 
                 if ( S_ISREG(mode) && fiops && fiops->permission ) {
                         EXIT;
-                        return fiops->permission(inode, mask);
+                        rc = fiops->permission(inode, mask);
+			goto out;
                 }
                 if ( S_ISDIR(mode) && diops && diops->permission ) {
                         EXIT;
-                        return diops->permission(inode, mask);
+                        rc = diops->permission(inode, mask);
+			goto out;
                 }
         }
 
-        /* The cache filesystem doesn't have its own permission function,
-         * but we don't want to duplicate the VFS code here.  In order
-         * to avoid looping from permission calling this function again,
-         * we temporarily override the permission operation while we call
-         * the VFS permission function.
-         */
-        inode->i_op->permission = NULL;
-        rc = permission(inode, mask);
-        inode->i_op->permission = &presto_permission;
+        rc = vfs_permission(inode, mask);
 
         EXIT;
+
+ out:
+	unlock_kernel();
         return rc;
 }
 
diff -aur -X /mnt/elbrus/home/pmenage/dontdiff linux-2.5.21/fs/namei.c linux-2.5.21-permission/fs/namei.c
--- linux-2.5.21/fs/namei.c	Sat Jun  8 22:28:50 2002
+++ linux-2.5.21-permission/fs/namei.c	Sun Jun  9 20:25:31 2002
@@ -204,13 +204,8 @@
 
 int permission(struct inode * inode,int mask)
 {
-	if (inode->i_op && inode->i_op->permission) {
-		int retval;
-		lock_kernel();
-		retval = inode->i_op->permission(inode, mask);
-		unlock_kernel();
-		return retval;
-	}
+	if (inode->i_op && inode->i_op->permission)
+		return inode->i_op->permission(inode, mask);
 	return vfs_permission(inode, mask);
 }
 
diff -aur -X /mnt/elbrus/home/pmenage/dontdiff linux-2.5.21/fs/nfs/dir.c linux-2.5.21-permission/fs/nfs/dir.c
--- linux-2.5.21/fs/nfs/dir.c	Sat Jun  8 22:29:55 2002
+++ linux-2.5.21-permission/fs/nfs/dir.c	Sun Jun  9 20:30:36 2002
@@ -1123,6 +1123,8 @@
 	    && error != -EACCES)
 		goto out;
 
+	lock_kernel();
+
 	error = NFS_PROTO(inode)->access(inode, mask, 0);
 
 	if (error == -EACCES && NFS_CLIENT(inode)->cl_droppriv &&
@@ -1130,6 +1132,8 @@
 	    (current->fsuid != current->uid || current->fsgid != current->gid))
 		error = NFS_PROTO(inode)->access(inode, mask, 1);
 
+	unlock_kernel();
+
  out:
 	return error;
 }