mm/cma: Move dma contiguous changes into a seperate config

We want to use CMA for allocating hash page table and real mode area for
PPC64. Hence move DMA contiguous related changes into a seperate config
so that ppc64 can enable CMA without requiring DMA contiguous.

Acked-by: Michal Nazarewicz <mina86@mina86.com>
Acked-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
[removed defconfig changes]
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>

1 files changed, 24 insertions, 0 deletions

diff --git a/mm/Kconfig b/mm/Kconfig
index e742d06285b7..26a5f815cfc3 100644
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -477,3 +477,27 @@ config FRONTSWAP
           and swap data is stored as normal on the matching swap device.
 
           If unsure, say Y to enable frontswap.
+
+config CMA
+        bool "Contiguous Memory Allocator"
+        depends on HAVE_MEMBLOCK
+        select MIGRATION
+        select MEMORY_ISOLATION
+        help
+          This enables the Contiguous Memory Allocator which allows other
+          subsystems to allocate big physically-contiguous blocks of memory.
+          CMA reserves a region of memory and allows only movable pages to
+          be allocated from it. This way, the kernel can use the memory for
+          pagecache and when a subsystem requests for contiguous area, the
+          allocated pages are migrated away to serve the contiguous request.
+
+          If unsure, say "n".
+
+config CMA_DEBUG
+        bool "CMA debug messages (DEVELOPMENT)"
+        depends on DEBUG_KERNEL && CMA
+        help
+          Turns on debug messages in CMA.  This produces KERN_DEBUG
+          messages for every CMA call as well as various messages while
+          processing calls such as dma_alloc_from_contiguous().
+          This option does not affect warning and error messages.