Currently, there are two users on CMA functionality, one is the DMA subsystem and the other is the kvm on powerpc. They have their own code to manage CMA reserved area even if they looks really similar. >From my guess, it is caused by some needs on bitmap management. Kvm side wants to maintain bitmap not for 1 page, but for more size. Eventually it use bitmap where one bit represents 64 pages. When I implement CMA related patches, I should change those two places to apply my change and it seem to be painful to me. I want to change this situation and reduce future code management overhead through this patch. This change could also help developer who want to use CMA in their new feature development, since they can use CMA easily without copying & pasting this reserved area management code. v2: Although this patchset looks very different with v1, the end result, that is, mm/cma.c is same with v1's one. So I carry Ack to patch 6-7. Patch 1-5 prepare some features to cover ppc kvm's requirements. Patch 6-7 generalize CMA reserved area management code and change users to use it. Patch 8-10 clean-up minor things. Joonsoo Kim (10): DMA, CMA: clean-up log message DMA, CMA: fix possible memory leak DMA, CMA: separate core cma management codes from DMA APIs DMA, CMA: support alignment constraint on cma region DMA, CMA: support arbitrary bitmap granularity CMA: generalize CMA reserved area management functionality PPC, KVM, CMA: use general CMA reserved area management framework mm, cma: clean-up cma allocation error path mm, cma: move output param to the end of param list mm, cma: use spinlock instead of mutex arch/powerpc/kvm/book3s_hv_builtin.c | 17 +- arch/powerpc/kvm/book3s_hv_cma.c | 240 ------------------------ arch/powerpc/kvm/book3s_hv_cma.h | 27 --- drivers/base/Kconfig | 10 - drivers/base/dma-contiguous.c | 248 ++----------------------- include/linux/cma.h | 12 ++ include/linux/dma-contiguous.h | 3 +- mm/Kconfig | 11 ++ mm/Makefile | 1 + mm/cma.c | 333 ++++++++++++++++++++++++++++++++++ 10 files changed, 382 insertions(+), 520 deletions(-) delete mode 100644 arch/powerpc/kvm/book3s_hv_cma.c delete mode 100644 arch/powerpc/kvm/book3s_hv_cma.h create mode 100644 include/linux/cma.h create mode 100644 mm/cma.c -- 1.7.9.5 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>