[PATCH 6/8] drivers: add Contiguous Memory Allocator

[Marek Szyprowski]

Hello,

On Tuesday, July 05, 2011 9:42 AM Marek Szyprowski wrote:

> The Contiguous Memory Allocator is a set of helper functions for DMA
> mapping framework that improves allocations of contiguous memory chunks.
> 
> CMA grabs memory on system boot, marks it with CMA_MIGRATE_TYPE and
> gives back to the system. Kernel is allowed to allocate movable pages
> within CMA's managed memory so that it can be used for example for page
> cache when DMA mapping do not use it. On dma_alloc_from_contiguous()
> request such pages are migrated out of CMA area to free required
> contiguous block and fulfill the request. This allows to allocate large
> contiguous chunks of memory at any time assuming that there is enough
> free memory available in the system.
> 
> This code is heavily based on earlier works by Michal Nazarewicz.
> 
> Signed-off-by: Marek Szyprowski <m.szyprowski at samsung.com>
> Signed-off-by: Kyungmin Park <kyungmin.park at samsung.com>
> CC: Michal Nazarewicz <mina86 at mina86.com>
> ---
>  drivers/base/Kconfig           |   77 +++++++++
>  drivers/base/Makefile          |    1 +
>  drivers/base/dma-contiguous.c  |  367
> ++++++++++++++++++++++++++++++++++++++++
>  include/linux/dma-contiguous.h |  104 +++++++++++
>  4 files changed, 549 insertions(+), 0 deletions(-)
>  create mode 100644 drivers/base/dma-contiguous.c
>  create mode 100644 include/linux/dma-contiguous.h
> 
> diff --git a/drivers/base/Kconfig b/drivers/base/Kconfig
> index d57e8d0..95ae1a7 100644
> --- a/drivers/base/Kconfig
> +++ b/drivers/base/Kconfig
> @@ -168,4 +168,81 @@ config SYS_HYPERVISOR
>  	bool
>  	default n
> 
> +config CMA
> +	bool "Contiguous Memory Allocator"
> +	depends HAVE_DMA_CONTIGUOUS && HAVE_MEMBLOCK

The above line should be obviously "depends on HAVE_DMA_CONTIGUOUS &&
HAVE_MEMBLOCK".
I'm sorry for posting broken version. 

(snipped)

Best regards
-- 
Marek Szyprowski
Samsung Poland R&D Center