drm/i915: Selectively enable self-reclaim

drm/i915: Selectively enable self-reclaim

commit 4bdadb9785696439c6e2b3efe34aa76df1149c83 upstream.

Having missed the ENOMEM return via i915_gem_fault(), there are probably
other paths that I also missed. By not enabling NORETRY by default these
paths can run the shrinker and take memory from the system (but not from
our own inactive lists because our shrinker can not run whilst we hold
the struct mutex) and this may allow the system to survive a little longer
whilst our drivers consume all available memory.

References:
  OOM killer unexpectedly called with kernel 2.6.32
  http://bugzilla.kernel.org/show_bug.cgi?id=14933

v2: Pass gfp into page mapping.
v3: Use new read_cache_page_gfp() instead of open-coding.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Hugh Dickins <hugh.dickins@tiscali.co.uk>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: Eric Anholt <eric@anholt.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>