From mboxrd@z Thu Jan 1 00:00:00 1970 From: m.szyprowski@samsung.com (Marek Szyprowski) Date: Tue, 03 Jul 2012 09:20:29 +0200 Subject: [PATCH v4] mm: cma: add a simple kernel module as the helper to test CMA In-Reply-To: <1331120259-30780-1-git-send-email-Barry.Song@csr.com> References: <1331120259-30780-1-git-send-email-Barry.Song@csr.com> Message-ID: <03e601cd58ec$5b8177b0$12846710$%szyprowski@samsung.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Hello, On Wednesday, March 07, 2012 12:38 PM Barry Song wrote: > From: Barry Song > > Any write request to /dev/cma_test will let the module to allocate memory from > CMA, for example: > > 1st time > $ echo 1024 > /dev/cma_test > will require cma_test to request 1MB(1024KB) > 2nd time > $ echo 2048 > /dev/cma_test > will require cma_test to request 2MB(2048KB) > > Any read request to /dev/cma_test will let the module to free the 1st valid > memory from CMA, for example: > > 1st time > $ cat /dev/cma_test > will require cma_test to free the 1MB allocated in the first write request > 2nd time > $ cat /dev/cma_test > will require cma_test to free the 2MB allocated in the second write request > > Signed-off-by: Barry Song > --- > tools/cma/Makefile | 13 +++++ > tools/cma/cma_test.c | 140 ++++++++++++++++++++++++++++++++++++++++++++++++++ I'm sorry for such a long delay in processing this patch, but I wanted first to be sure that the core CMA code gets into mainline, then I got busy with other dma-mapping related stuff. IMHO the right place for such code is in drivers/misc instead of tools/cma. This patch contains a kernel module source code so it should be put with other kernel modules. tools/ directory is aimed to contain user space code useful for developing and testing Linux kernel. Make sure that you also add Greg Kroah-Hartman on CC:, he maintains misc drivers. > (snipped) Best regards -- Marek Szyprowski Samsung Poland R&D Center