ion: system_heap: only use low gfp flags for order-0 pages

By trying a little harder to get high-order pages (by virtue of the
liberal gfp flags used for high-order allocations) we can actually
optimize performance since high-order pages seem to help a lot. Only use
the low-order flags as a last resort, when trying to allocate an order-0
page.

Change-Id: If8d8f4b1b4503b0c7546cf5a4bcdcaecd2bb5905
Signed-off-by: Mitchel Humpherys <mitchelh@codeaurora.org>
gpu: ion: system_heap: add support for 2MB allocations

Enable 2MB (order 9) allocations from the system heap. This improves the
performance of some heavyweight use cases. The benefit is especially
large for use cases where the buffer is mapped into an IOMMU since we
can leverage the 2MB IOMMU page table mappings.

Change-Id: I869733089b9ccba8090bbca80aac7b5f248b335e
Signed-off-by: Mitchel Humpherys <mitchelh@codeaurora.org>
Revert "3.4.83rc"

This reverts commit 8cf3412d65300a35cc82953d60c30c2fce27a1d7.
3.4.83rc2
network patches