From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Joonsoo Kim" Subject: RE: [PATCH 4/4] drivers: dma-contiguous: add initialization from device tree Date: Fri, 4 Jul 2014 14:52:44 +0900 Message-ID: <00b501cf974c$2db1a800$8914f800$@lge.com> References: <1404298132-6050-1-git-send-email-m.szyprowski@samsung.com> <1404298132-6050-5-git-send-email-m.szyprowski@samsung.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1404298132-6050-5-git-send-email-m.szyprowski@samsung.com> Content-Language: ko List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=m.gmane.org@lists.infradead.org To: 'Marek Szyprowski' , linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linaro-mm-sig@lists.linaro.org, devicetree@vger.kernel.org, linux-doc@vger.kernel.org Cc: 'Mark Rutland' , 'Jon Medhurst' , 'Benjamin Herrenschmidt' , 'Tomasz Figa' , 'Will Deacon' , 'Tomasz Figa' , 'Paul Mackerras' , 'Arnd Bergmann' , 'Josh Cartwright' , 'Catalin Marinas' , 'Grant Likely' , 'Laura Abbott' , 'Ian Campbell' , 'Pawel Moll' , 'Stephen Warren' , 'Sascha Hauer' , 'Michal Nazarewicz' , 'Marc' , 'Nishanth Peethambaran' , 'Rob Herring' , "'Aneesh Kumar K.V.'" , 'Kumar Gala' List-Id: devicetree@vger.kernel.org > -----Original Message----- > From: Marek Szyprowski [mailto:m.szyprowski@samsung.com] > Sent: Wednesday, July 02, 2014 7:49 PM > To: linux-kernel@vger.kernel.org; linux-arm-kernel@lists.infradead.org; > linaro-mm-sig@lists.linaro.org; devicetree@vger.kernel.org; linux- > doc@vger.kernel.org > Cc: Marek Szyprowski; Benjamin Herrenschmidt; Arnd Bergmann; Michal > Nazarewicz; Grant Likely; Tomasz Figa; Sascha Hauer; Laura Abbott; Rob > Herring; Olof Johansson; Pawel Moll; Mark Rutland; Stephen Warren; Ian > Campbell; Tomasz Figa; Kumar Gala; Nishanth Peethambaran; Marc; Josh > Cartwright; Catalin Marinas; Will Deacon; Paul Mackerras; Jon Medhurst; > Joonsoo Kim; Aneesh Kumar K.V.; Andrew Morton > Subject: [PATCH 4/4] drivers: dma-contiguous: add initialization from > device tree > > Add a code to create CMA region from reserved memory and add support for > handling 'shared-dma-pool' reserved-memory device tree nodes. > > Signed-off-by: Marek Szyprowski > --- > drivers/base/dma-contiguous.c | 67 > +++++++++++++++++++++++++++++++++++++++++ > include/linux/cma.h | 3 ++ > mm/cma.c | 69 ++++++++++++++++++++++++++++++++----------- > 3 files changed, 122 insertions(+), 17 deletions(-) > > diff --git a/drivers/base/dma-contiguous.c b/drivers/base/dma-contiguous.c > index 6606abdf880c..b77ea8bac176 100644 > --- a/drivers/base/dma-contiguous.c > +++ b/drivers/base/dma-contiguous.c > @@ -211,3 +211,70 @@ bool dma_release_from_contiguous(struct device *dev, > struct page *pages, > { > return cma_release(dev_get_cma_area(dev), pages, count); > } > + > +/* > + * Support for reserved memory regions defined in device tree > + */ > +#ifdef CONFIG_OF_RESERVED_MEM > +#include > +#include > +#include > + > +#undef pr_fmt > +#define pr_fmt(fmt) fmt > + > +static void rmem_cma_device_init(struct reserved_mem *rmem, struct device > *dev) > +{ > + struct cma *cma = rmem->priv; > + dev_set_cma_area(dev, cma); > +} > + > +static void rmem_cma_device_release(struct reserved_mem *rmem, > + struct device *dev) > +{ > + dev_set_cma_area(dev, NULL); > +} > + > +static const struct reserved_mem_ops rmem_cma_ops = { > + .device_init = rmem_cma_device_init, > + .device_release = rmem_cma_device_release, > +}; > + > +static int __init rmem_cma_setup(struct reserved_mem *rmem) > +{ > + phys_addr_t align = PAGE_SIZE << max(MAX_ORDER - 1, > pageblock_order); > + phys_addr_t mask = align - 1; > + unsigned long node = rmem->fdt_node; > + struct cma *cma; > + int err; > + > + if (!of_get_flat_dt_prop(node, "reusable", NULL) || > + of_get_flat_dt_prop(node, "no-map", NULL)) > + return -EINVAL; > + > + if ((rmem->base & mask) || (rmem->size & mask)) { > + pr_err("Reserved memory: incorrect alignment of CMA > region\n"); > + return -EINVAL; > + } > + > + err = cma_init_reserved_mem(rmem->base, rmem->size, 0, &cma); > + if (err) { > + pr_err("Reserved memory: unable to setup CMA region\n"); > + return err; > + } > + /* Architecture specific contiguous memory fixup. */ > + dma_contiguous_early_fixup(rmem->base, rmem->size); > + > + if (of_get_flat_dt_prop(node, "linux,cma-default", NULL)) > + dma_contiguous_set_default(cma); > + > + rmem->ops = &rmem_cma_ops; > + rmem->priv = cma; > + > + pr_info("Reserved memory: created CMA memory pool at %pa, size %ld > MiB\n", > + &rmem->base, (unsigned long)rmem->size / SZ_1M); > + > + return 0; > +} > +RESERVEDMEM_OF_DECLARE(cma, "shared-dma-pool", rmem_cma_setup); > +#endif > diff --git a/include/linux/cma.h b/include/linux/cma.h > index 32cab7a425f9..9a18a2b1934c 100644 > --- a/include/linux/cma.h > +++ b/include/linux/cma.h > @@ -16,6 +16,9 @@ extern int __init cma_declare_contiguous(phys_addr_t > size, > phys_addr_t base, phys_addr_t limit, > phys_addr_t alignment, unsigned int order_per_bit, > bool fixed, struct cma **res_cma); > +extern int cma_init_reserved_mem(phys_addr_t size, > + phys_addr_t base, int order_per_bit, > + struct cma **res_cma); > extern struct page *cma_alloc(struct cma *cma, int count, unsigned int > align); > extern bool cma_release(struct cma *cma, struct page *pages, int count); > #endif > diff --git a/mm/cma.c b/mm/cma.c > index 4b251b037e1b..c3d84016d432 100644 > --- a/mm/cma.c > +++ b/mm/cma.c > @@ -140,6 +140,54 @@ static int __init cma_init_reserved_areas(void) > core_initcall(cma_init_reserved_areas); > > /** > + * cma_init_reserved_mem() - create custom contiguous area from reserved > memory > + * @base: Base address of the reserved area > + * @size: Size of the reserved area (in bytes), > + * @order_per_bit: Order of pages represented by one bit on bitmap. > + * @res_cma: Pointer to store the created cma region. > + * > + * This function creates custom contiguous area from already reserved > memory. > + */ > +int __init cma_init_reserved_mem(phys_addr_t base, phys_addr_t size, > + int order_per_bit, struct cma **res_cma) > +{ > + struct cma *cma; > + phys_addr_t alignment; > + > + /* Sanity checks */ > + if (cma_area_count == ARRAY_SIZE(cma_areas)) { > + pr_err("Not enough slots for CMA reserved regions!\n"); > + return -ENOSPC; > + } > + > + if (!size || !memblock_is_region_reserved(base, size)) > + return -EINVAL; > + > + /* ensure minimal alignment requied by mm core */ > + alignment = PAGE_SIZE << max(MAX_ORDER - 1, pageblock_order); > + > + /* alignment should be aligned with order_per_bit */ > + if (!IS_ALIGNED(alignment >> PAGE_SHIFT, 1 << order_per_bit)) > + return -EINVAL; > + > + if (ALIGN(base, alignment) != base || ALIGN(size, alignment) != > size) > + return -EINVAL; > + > + /* > + * Each reserved area must be initialised later, when more kernel > + * subsystems (like slab allocator) are available. > + */ > + cma = &cma_areas[cma_area_count]; > + cma->base_pfn = PFN_DOWN(base); > + cma->count = size >> PAGE_SHIFT; > + cma->order_per_bit = order_per_bit; > + *res_cma = cma; > + cma_area_count++; > + > + return 0; > +} > + > +/** > * cma_declare_contiguous() - reserve custom contiguous area > * @base: Base address of the reserved area optional, use 0 for any > * @size: Size of the reserved area (in bytes), > @@ -162,18 +210,12 @@ int __init cma_declare_contiguous(phys_addr_t base, > phys_addr_t alignment, unsigned int order_per_bit, > bool fixed, struct cma **res_cma) > { > - struct cma *cma; > - int ret = 0; > + int ret; > > pr_debug("%s(size %lx, base %08lx, limit %08lx alignment %08lx)\n", > __func__, (unsigned long)size, (unsigned long)base, > (unsigned long)limit, (unsigned long)alignment); > > - if (cma_area_count == ARRAY_SIZE(cma_areas)) { > - pr_err("Not enough slots for CMA reserved regions!\n"); > - return -ENOSPC; > - } > - Hello, Marek. After this change, if we have not enough cma_areas, memory will leak. I think that we need separate function to check constraint and this function should be called before reserving memory in cma_declare_contiguous(). BTW, this mail doesn't appear in LKML. What happens? :) Thanks.