TOMOYO: Return appropriate value to poll().

"struct file_operations"->poll() expects "unsigned int" return value.
All files in /sys/kernel/security/tomoyo/ directory other than
/sys/kernel/security/tomoyo/query and /sys/kernel/security/tomoyo/audit should
return POLLIN | POLLRDNORM | POLLOUT | POLLWRNORM rather than -ENOSYS.
Also, /sys/kernel/security/tomoyo/query and /sys/kernel/security/tomoyo/audit
should return POLLOUT | POLLWRNORM rather than 0 when there is no data to read.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <james.l.morris@oracle.com>
diff --git a/security/tomoyo/securityfs_if.c b/security/tomoyo/securityfs_if.c
index 482b2a5..8592f2fc 100644
--- a/security/tomoyo/securityfs_if.c
+++ b/security/tomoyo/securityfs_if.c
@@ -157,9 +157,10 @@
  * tomoyo_poll - poll() for /sys/kernel/security/tomoyo/ interface.
  *
  * @file: Pointer to "struct file".
- * @wait: Pointer to "poll_table".
+ * @wait: Pointer to "poll_table". Maybe NULL.
  *
- * Returns 0 on success, negative value otherwise.
+ * Returns POLLIN | POLLRDNORM | POLLOUT | POLLWRNORM if ready to read/write,
+ * POLLOUT | POLLWRNORM otherwise.
  */
 static unsigned int tomoyo_poll(struct file *file, poll_table *wait)
 {