From: Ian Abbott <abbotti@mev.co.uk>
Date: Fri, 8 Nov 2013 15:03:25 +0000 (+0000)
Subject: staging: comedi: use attach_lock semaphore during attach and detach
X-Git-Tag: v3.14-rc1~150^2~775^2~100
X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=bf11c134246e8f3cfa2582a3d2af84ed7dfd59b6;p=pandora-kernel.git

staging: comedi: use attach_lock semaphore during attach and detach

Acquire the `attach_lock` semaphore in the `struct comedi_device` while
modifying the `attached` flag.  This is a "write" acquire.  Note that
the main mutex in the `struct comedi_device` is also held at this time.
Tasks wishing to check the device is attached will need to either
acquire the main mutex, or "read" acquire the `attach_lock` semaphore,
or both in that order.

Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

Reading git-diff-tree failed