[PATCH] reiserfs: eliminate private use of struct file in xattr

After several posts and bug reports regarding interaction with the NULL
nameidata, here's a patch to clean up the mess with struct file in the
reiserfs xattr code.

As observed in several of the posts, there's really no need for struct file
to exist in the xattr code.  It was really only passed around due to the
f_op->readdir() and a_ops->{prepare,commit}_write prototypes requiring it.

reiserfs_prepare_write() and reiserfs_commit_write() don't actually use the
struct file passed to it, and the xattr code uses a private version of
reiserfs_readdir() to enumerate the xattr directories.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>