diff options
| author | Akinobu Mita <akinobu.mita@gmail.com> | 2014-06-04 16:06:50 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2014-06-04 16:53:57 -0700 |
| commit | 9c5a3621427da68afe6a078cadf807d2c8cc1d12 (patch) | |
| tree | b56df6020a1b966544dbb2b9f119bd883405e5a4 /arch/x86/Kconfig | |
| parent | d92ef66c4f8fdf7a24736b1ab6c48d32de9bfc07 (diff) | |
x86: enable DMA CMA with swiotlb
The DMA Contiguous Memory Allocator support on x86 is disabled when
swiotlb config option is enabled. So DMA CMA is always disabled on
x86_64 because swiotlb is always enabled. This attempts to support for
DMA CMA with enabling swiotlb config option.
The contiguous memory allocator on x86 is integrated in the function
dma_generic_alloc_coherent() which is .alloc callback in nommu_dma_ops
for dma_alloc_coherent().
x86_swiotlb_alloc_coherent() which is .alloc callback in swiotlb_dma_ops
tries to allocate with dma_generic_alloc_coherent() firstly and then
swiotlb_alloc_coherent() is called as a fallback.
The main part of supporting DMA CMA with swiotlb is that changing
x86_swiotlb_free_coherent() which is .free callback in swiotlb_dma_ops
for dma_free_coherent() so that it can distinguish memory allocated by
dma_generic_alloc_coherent() from one allocated by
swiotlb_alloc_coherent() and release it with dma_generic_free_coherent()
which can handle contiguous memory. This change requires making
is_swiotlb_buffer() global function.
This also needs to change .free callback in the dma_map_ops for amd_gart
and sta2x11, because these dma_ops are also using
dma_generic_alloc_coherent().
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Don Dutile <ddutile@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'arch/x86/Kconfig')
| -rw-r--r-- | arch/x86/Kconfig | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 896a411a4584..4a0137f6f032 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -41,7 +41,7 @@ config X86 select ARCH_WANT_OPTIONAL_GPIOLIB select ARCH_WANT_FRAME_POINTERS select HAVE_DMA_ATTRS - select HAVE_DMA_CONTIGUOUS if !SWIOTLB + select HAVE_DMA_CONTIGUOUS select HAVE_KRETPROBES select GENERIC_EARLY_IOREMAP select HAVE_OPTPROBES |