From: Thomas Hellstrom <thellstrom@vmware.com>
Date: Tue, 25 Feb 2014 18:57:44 +0000 (+0100)
Subject: drm: Protect the master management with a drm_device::master_mutex v3
X-Git-Tag: upstream/snapshot3+hdmi~1^2~19
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=be0e079c2abfc76e4a6da598ecccfbc6ed08eeeb;hp=be0e079c2abfc76e4a6da598ecccfbc6ed08eeeb;p=platform%2Fadaptation%2Frenesas_rcar%2Frenesas_kernel.git

drm: Protect the master management with a drm_device::master_mutex v3

The master management was previously protected by the drm_device::struct_mutex.
In order to avoid locking order violations in a reworked dropped master
security check in the vmwgfx driver, break it out into a separate master_mutex.
Locking order is master_mutex -> struct_mutex.

Also remove drm_master::blocked since it's not used.

v2: Add an inline comment about what drm_device::master_mutex is protecting.
v3: Remove unneeded struct_mutex locks. Fix error returns in
    drm_setmaster_ioctl().

Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Brian Paul <brianp@vmware.com>
Reviewed-by: David Herrmann <dh.herrmann@gmail.com>
Acked-by: Daniel Vetter <daniel@ffwll.ch>
(cherry picked from commit c996fd0b956450563454e7ccc97a82ca31f9d043)
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>

Conflicts:
	drivers/gpu/drm/drm_stub.c
---