io-mapping: ensure io_mapping_map_atomic _is_ atomic
authorDaniel Vetter <daniel.vetter@ffwll.ch>
Wed, 28 Sep 2011 09:57:23 +0000 (11:57 +0200)
committerKeith Packard <keithp@keithp.com>
Thu, 20 Oct 2011 22:26:17 +0000 (15:26 -0700)
commit24dd85ff723f142093f44244764b9b5c152235b8
tree142aaa2cf68b307e584ed1ba9f40a951ae46828c
parent8ffc02468145ac92b1b88896e0f18bd7bcd52591
io-mapping: ensure io_mapping_map_atomic _is_ atomic

For the !HAVE_ATOMIC_IOMAP case the stub functions did not call
pagefault_disable/_enable. The i915 driver relies on the map
actually being atomic, otherwise it can deadlock with it's own
pagefault handler in the gtt pwrite fastpath.

This is exercised by gem_mmap_gtt from the intel-gpu-toosl gem
testsuite.

v2: Chris Wilson noted the lack of an include.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=38115
Cc: stable@kernel.org
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Keith Packard <keithp@keithp.com>
include/linux/io-mapping.h