On Tue, Jul 20, 2010 at 05:51:25PM +0200, Michal Nazarewicz wrote: > The Contiguous Memory Allocator framework is a set of APIs for > allocating physically contiguous chunks of memory. > > Various chips require contiguous blocks of memory to operate. Those > chips include devices such as cameras, hardware video decoders and > encoders, etc. > > The code is highly modular and customisable to suit the needs of > various users. Set of regions reserved for CMA can be configured on > run-time and it is easy to add custom allocator algorithms if one > has such need. > > Signed-off-by: Michal Nazarewicz <m.nazarewicz@xxxxxxxxxxx> > Signed-off-by: Kyungmin Park <kyungmin.park@xxxxxxxxxxx> > Reviewed-by: Pawel Osciak <p.osciak@xxxxxxxxxxx> > --- > Documentation/cma.txt | 435 +++++++++++++++++++ > Documentation/kernel-parameters.txt | 7 + > include/linux/cma-int.h | 183 ++++++++ > include/linux/cma.h | 92 ++++ > mm/Kconfig | 41 ++ > mm/Makefile | 3 + > mm/cma-allocators.h | 42 ++ > mm/cma-best-fit.c | 360 ++++++++++++++++ > mm/cma.c | 778 +++++++++++++++++++++++++++++++++++ > 9 files changed, 1941 insertions(+), 0 deletions(-) > create mode 100644 Documentation/cma.txt > create mode 100644 include/linux/cma-int.h > create mode 100644 include/linux/cma.h > create mode 100644 mm/cma-allocators.h > create mode 100644 mm/cma-best-fit.c > create mode 100644 mm/cma.c > > diff --git a/Documentation/cma.txt b/Documentation/cma.txt > new file mode 100644 > index 0000000..7edc20a > --- /dev/null > +++ b/Documentation/cma.txt > @@ -0,0 +1,435 @@ > + -*- org -*- > + > +* Contiguous Memory Allocator > + > + The Contiguous Memory Allocator (CMA) is a framework, which allows > + setting up a machine-specific configuration for physically-contiguous > + memory management. Memory for devices is then allocated according > + to that configuration. > + > + The main role of the framework is not to allocate memory, but to > + parse and manage memory configurations, as well as to act as an > + in-between between device drivers and pluggable allocators. It is > + thus not tied to any memory allocation method or strategy. > + This topic seems very hot lately. I recently sent out a few RFCs that implement something called a Virtual Contiguous Memory Manager that does what this patch does, and works for IOMMU and works for CPU mappings. It also does multihomed memory targeting (use physical set 1 memory for A allocations and use physical memory set 2 for B allocations). Check out: mm: iommu: An API to unify IOMMU, CPU and device memory management mm: iommu: A physical allocator for the VCMM mm: iommu: The Virtual Contiguous Memory Manager It unifies IOMMU and physical mappings by creating a one-to-one software IOMMU for all devices that map memory physically. It looks like you've got some good ideas though. Perhaps we can leverage each other's work. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxxx For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>