saner FASYNC handling on file close

As it is, all instances of ->release() for files that have ->fasync()
need to remember to evict file from fasync lists; forgetting that
creates a hole and we actually have a bunch that *does* forget.

So let's keep our lives simple - let __fput() check FASYNC in
file->f_flags and call ->fasync() there if it's been set.  And lose that
crap in ->release() instances - leaving it there is still valid, but we
don't have to bother anymore.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/file_table.c b/fs/file_table.c
index efc06fa..5ad0eca 100644
--- a/fs/file_table.c
+++ b/fs/file_table.c
@@ -269,6 +269,10 @@
 	eventpoll_release(file);
 	locks_remove_flock(file);
 
+	if (unlikely(file->f_flags & FASYNC)) {
+		if (file->f_op && file->f_op->fasync)
+			file->f_op->fasync(-1, file, 0);
+	}
 	if (file->f_op && file->f_op->release)
 		file->f_op->release(inode, file);
 	security_file_free(file);