[Intel-gfx] use exact allocation for dma coherent memory

[Christoph Hellwig]

On Fri, Jun 14, 2019 at 03:47:10PM +0200, Christoph Hellwig wrote:
> Switching to a slightly cleaned up alloc_pages_exact is pretty easy,
> but it turns out that because we didn't filter valid gfp_t flags
> on the DMA allocator, a bunch of drivers were passing __GFP_COMP
> to it, which is rather bogus in too many ways to explain.  Arm has
> been filtering it for a while, but this series instead tries to fix
> the drivers and warn when __GFP_COMP is passed, which makes it much
> larger than just adding the functionality.

Dear driver maintainers,

can you look over the patches touching your drivers, please?  I'd
like to get as much as possible of the driver patches into this
merge window, so that it can you through your maintainer trees.