[PATCH] Intermezzo should call vfs_permission

[Matthew Wilcox <willy@debian.org>]

This patch fixes some extremely naughty behaviour by intermezzo where it
overrides a member of an inode's i_op -- which is probably shared between
all inodes of that filesystem type!  It turns out that the intended
behaviour is accomplished equally well by just calling vfs_permission().

Index: fs/intermezzo/dir.c
===================================================================
RCS file: /var/cvs/linux-2.6/fs/intermezzo/dir.c,v
retrieving revision 1.12
diff -u -p -r1.12 dir.c
--- a/fs/intermezzo/dir.c	8 Oct 2003 20:52:46 -0000	1.12
+++ b/fs/intermezzo/dir.c	31 Oct 2003 03:10:01 -0000
@@ -835,10 +835,9 @@ int presto_permission(struct inode *inod
 {
         unsigned short mode = inode->i_mode;
         struct presto_cache *cache;
-        int rc;
 
         ENTRY;
-        if ( presto_can_ilookup() && !(mask & S_IWOTH)) {
+        if (presto_can_ilookup() && !(mask & S_IWOTH)) {
                 CDEBUG(D_CACHE, "ilookup on %ld OK\n", inode->i_ino);
                 EXIT;
                 return 0;
@@ -861,18 +860,8 @@ int presto_permission(struct inode *inod
                 }
         }
 
-        /* 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, nd);
-        inode->i_op->permission = &presto_permission;
-
         EXIT;
-        return rc;
+        return vfs_permission(inode, mask);
 }
 
 

-- 
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