Since nfsv4 actually keeps around the file descriptors it gets from open
(instead of just using them for a single read or write operation), we need to
make sure that we can do RDWR opens and not just RDONLY/WRONLY.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu> Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>