fanotify: reorganize loop in fanotify_read()
authorJan Kara <jack@suse.cz>
Thu, 3 Apr 2014 21:46:35 +0000 (14:46 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Thu, 3 Apr 2014 23:20:51 +0000 (16:20 -0700)
Swap the error / "read ok" branches in the main loop of fanotify_read().
We will grow the "read ok" part in the next patch and this makes the
indentation easier.  Also it is more common to have error conditions
inside an 'if' instead of the fast path.

Signed-off-by: Jan Kara <jack@suse.cz>
Cc: Eric Paris <eparis@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
fs/notify/fanotify/fanotify_user.c

index 2a57278afb80d1df0d235b9f8a55ffccee9542e2..f1097f56137e0ad4536e4b80e7a892c8e064e8b0 100644 (file)
@@ -275,35 +275,37 @@ static ssize_t fanotify_read(struct file *file, char __user *buf,
                kevent = get_one_event(group, count);
                mutex_unlock(&group->notification_mutex);
 
-               if (kevent) {
+               if (IS_ERR(kevent)) {
                        ret = PTR_ERR(kevent);
-                       if (IS_ERR(kevent))
+                       break;
+               }
+
+               if (!kevent) {
+                       ret = -EAGAIN;
+                       if (file->f_flags & O_NONBLOCK)
                                break;
-                       ret = copy_event_to_user(group, kevent, buf);
-                       /*
-                        * Permission events get queued to wait for response.
-                        * Other events can be destroyed now.
-                        */
-                       if (!(kevent->mask & FAN_ALL_PERM_EVENTS))
-                               fsnotify_destroy_event(group, kevent);
-                       if (ret < 0)
+
+                       ret = -ERESTARTSYS;
+                       if (signal_pending(current))
+                               break;
+
+                       if (start != buf)
                                break;
-                       buf += ret;
-                       count -= ret;
+                       schedule();
                        continue;
                }
 
-               ret = -EAGAIN;
-               if (file->f_flags & O_NONBLOCK)
-                       break;
-               ret = -ERESTARTSYS;
-               if (signal_pending(current))
-                       break;
-
-               if (start != buf)
+               ret = copy_event_to_user(group, kevent, buf);
+               /*
+                * Permission events get queued to wait for response.  Other
+                * events can be destroyed now.
+                */
+               if (!(kevent->mask & FAN_ALL_PERM_EVENTS))
+                       fsnotify_destroy_event(group, kevent);
+               if (ret < 0)
                        break;
-
-               schedule();
+               buf += ret;
+               count -= ret;
        }
 
        finish_wait(&group->notification_waitq, &wait);