Re: [RFC 04/10] Temporary struct vfs_lookup in file_permission

On Wednesday 08 August 2007 19:58, Josef Sipek wrote:
On Wed, Aug 08, 2007 at 07:16:26PM +0200, Andreas Gruenbacher wrote:
Create a temporary struct vfs_lookup in file_permission() instead of
passing a NULL value.

Signed-off-by: Andreas Gruenbacher <ag@xxxxxxxxxxx>

---
fs/namei.c | 11 ++++++-----
1 file changed, 6 insertions(+), 5 deletions(-)

--- a/fs/namei.c
+++ b/fs/namei.c
@@ -292,14 +292,15 @@ int vfs_permission(struct vfs_lookup *lo
*
* Used to check for read/write/execute permissions on an already opened
* file.
- *
- * Note:
- * Do not use this function in new code. All access checks should
- * be done using vfs_permission().

Should this comment be removed?

IMO yes. If vfs_permission() works for a piece of code it's the obvious
preference. If on the other hand you really need to check permissions on a
file, then why not use this function?

*/
int file_permission(struct file *file, int mask)
{
- return permission(file->f_path.dentry->d_inode, mask, NULL);
+ struct vfs_lookup lookup;
+
+ lookup.path = file->f_path;
+ lookup.flags = 0;

I tend to find this little bit cleaner:

struct vfs_lookup lookup = {
.path = file->f_path,
.flags = 0,
};

I didn't use initializers because they initialize the entire data structure.
In case of struct vfs_lookup, unless the LOOKUP_OPEN flag is set, then the
open_intent doesn't need initialization. We could use a DEFINE_... macro; not
sure this would improve anything though.

+
+ return permission(file->f_path.dentry->d_inode, mask, &lookup);
}

/*

Thanks,
Andreas
-
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