From a2547380393ac82c659b40182b0da8d05a8365f3 Mon Sep 17 00:00:00 2001 From: Marek Szyprowski Date: Mon, 29 Jul 2013 14:31:45 +0200 Subject: [PATCH] drivers: dma-contiguous: clean source code and prepare for device tree This patch cleans the initialization of dma contiguous framework. The all-in-one dma_declare_contiguous() function is now separated into dma_contiguous_reserve_area() which only steals the the memory from memblock allocator and dma_contiguous_add_device() function, which assigns given device to the specified reserved memory area. This improves the flexibility in defining contiguous memory areas and assigning device to them, because now it is possible to assign more than one device to the given contiguous memory area. Such split in initialization procedure is also required for upcoming device tree support. Signed-off-by: Marek Szyprowski Acked-by: Kyungmin Park Acked-by: Michal Nazarewicz Acked-by: Tomasz Figa --- arch/arm/include/asm/dma-contiguous.h | 1 - arch/x86/include/asm/dma-contiguous.h | 1 - drivers/base/dma-contiguous.c | 119 ++++++++++---------------- include/asm-generic/dma-contiguous.h | 28 ------ include/linux/device.h | 2 +- include/linux/dma-contiguous.h | 62 +++++++++++++- 6 files changed, 105 insertions(+), 108 deletions(-) delete mode 100644 include/asm-generic/dma-contiguous.h diff --git a/arch/arm/include/asm/dma-contiguous.h b/arch/arm/include/asm/dma-contiguous.h index e072bb2ba1b1..4f8e9e5514b1 100644 --- a/arch/arm/include/asm/dma-contiguous.h +++ b/arch/arm/include/asm/dma-contiguous.h @@ -5,7 +5,6 @@ #ifdef CONFIG_DMA_CMA #include -#include void dma_contiguous_early_fixup(phys_addr_t base, unsigned long size); diff --git a/arch/x86/include/asm/dma-contiguous.h b/arch/x86/include/asm/dma-contiguous.h index c09241659971..b4b38bacb404 100644 --- a/arch/x86/include/asm/dma-contiguous.h +++ b/arch/x86/include/asm/dma-contiguous.h @@ -4,7 +4,6 @@ #ifdef __KERNEL__ #include -#include static inline void dma_contiguous_early_fixup(phys_addr_t base, unsigned long size) { } diff --git a/drivers/base/dma-contiguous.c b/drivers/base/dma-contiguous.c index 0ca54421ce97..99802d6f3c60 100644 --- a/drivers/base/dma-contiguous.c +++ b/drivers/base/dma-contiguous.c @@ -96,7 +96,7 @@ static inline __maybe_unused phys_addr_t cma_early_percent_memory(void) #endif /** - * dma_contiguous_reserve() - reserve area for contiguous memory handling + * dma_contiguous_reserve() - reserve area(s) for contiguous memory handling * @limit: End address of the reserved memory (optional, 0 for any). * * This function reserves memory from early allocator. It should be @@ -124,22 +124,29 @@ void __init dma_contiguous_reserve(phys_addr_t limit) #endif } - if (selected_size) { + if (selected_size && !dma_contiguous_default_area) { pr_debug("%s: reserving %ld MiB for global area\n", __func__, (unsigned long)selected_size / SZ_1M); - dma_declare_contiguous(NULL, selected_size, 0, limit); + dma_contiguous_reserve_area(selected_size, 0, limit, + &dma_contiguous_default_area); } }; static DEFINE_MUTEX(cma_mutex); -static __init int cma_activate_area(unsigned long base_pfn, unsigned long count) +static int __init cma_activate_area(struct cma *cma) { - unsigned long pfn = base_pfn; - unsigned i = count >> pageblock_order; + int bitmap_size = BITS_TO_LONGS(cma->count) * sizeof(long); + unsigned long base_pfn = cma->base_pfn, pfn = base_pfn; + unsigned i = cma->count >> pageblock_order; struct zone *zone; + cma->bitmap = kzalloc(bitmap_size, GFP_KERNEL); + + if (!cma->bitmap) + return -ENOMEM; + WARN_ON_ONCE(!pfn_valid(pfn)); zone = page_zone(pfn_to_page(pfn)); @@ -153,92 +160,53 @@ static __init int cma_activate_area(unsigned long base_pfn, unsigned long count) } init_cma_reserved_pageblock(pfn_to_page(base_pfn)); } while (--i); - return 0; -} - -static __init struct cma *cma_create_area(unsigned long base_pfn, - unsigned long count) -{ - int bitmap_size = BITS_TO_LONGS(count) * sizeof(long); - struct cma *cma; - int ret = -ENOMEM; - - pr_debug("%s(base %08lx, count %lx)\n", __func__, base_pfn, count); - - cma = kmalloc(sizeof *cma, GFP_KERNEL); - if (!cma) - return ERR_PTR(-ENOMEM); - - cma->base_pfn = base_pfn; - cma->count = count; - cma->bitmap = kzalloc(bitmap_size, GFP_KERNEL); - if (!cma->bitmap) - goto no_mem; - - ret = cma_activate_area(base_pfn, count); - if (ret) - goto error; - - pr_debug("%s: returned %p\n", __func__, (void *)cma); - return cma; - -error: - kfree(cma->bitmap); -no_mem: - kfree(cma); - return ERR_PTR(ret); + return 0; } -static struct cma_reserved { - phys_addr_t start; - unsigned long size; - struct device *dev; -} cma_reserved[MAX_CMA_AREAS] __initdata; -static unsigned cma_reserved_count __initdata; +static struct cma cma_areas[MAX_CMA_AREAS]; +static unsigned cma_area_count; static int __init cma_init_reserved_areas(void) { - struct cma_reserved *r = cma_reserved; - unsigned i = cma_reserved_count; - - pr_debug("%s()\n", __func__); + int i; - for (; i; --i, ++r) { - struct cma *cma; - cma = cma_create_area(PFN_DOWN(r->start), - r->size >> PAGE_SHIFT); - if (!IS_ERR(cma)) - dev_set_cma_area(r->dev, cma); + for (i = 0; i < cma_area_count; i++) { + int ret = cma_activate_area(&cma_areas[i]); + if (ret) + return ret; } + return 0; } core_initcall(cma_init_reserved_areas); /** - * dma_declare_contiguous() - reserve area for contiguous memory handling - * for particular device - * @dev: Pointer to device structure. - * @size: Size of the reserved memory. - * @base: Start address of the reserved memory (optional, 0 for any). + * dma_contiguous_reserve_area() - reserve custom contiguous area + * @size: Size of the reserved area (in bytes), + * @base: Base address of the reserved area optional, use 0 for any * @limit: End address of the reserved memory (optional, 0 for any). + * @res_cma: Pointer to store the created cma region. * - * This function reserves memory for specified device. It should be - * called by board specific code when early allocator (memblock or bootmem) - * is still activate. + * This function reserves memory from early allocator. It should be + * called by arch specific code once the early allocator (memblock or bootmem) + * has been activated and all other subsystems have already allocated/reserved + * memory. This function allows to create custom reserved areas for specific + * devices. */ -int __init dma_declare_contiguous(struct device *dev, phys_addr_t size, - phys_addr_t base, phys_addr_t limit) +int __init dma_contiguous_reserve_area(phys_addr_t size, phys_addr_t base, + phys_addr_t limit, struct cma **res_cma) { - struct cma_reserved *r = &cma_reserved[cma_reserved_count]; + struct cma *cma = &cma_areas[cma_area_count]; phys_addr_t alignment; + int ret = 0; pr_debug("%s(size %lx, base %08lx, limit %08lx)\n", __func__, (unsigned long)size, (unsigned long)base, (unsigned long)limit); /* Sanity checks */ - if (cma_reserved_count == ARRAY_SIZE(cma_reserved)) { + if (cma_area_count == ARRAY_SIZE(cma_areas)) { pr_err("Not enough slots for CMA reserved regions!\n"); return -ENOSPC; } @@ -256,7 +224,7 @@ int __init dma_declare_contiguous(struct device *dev, phys_addr_t size, if (base) { if (memblock_is_region_reserved(base, size) || memblock_reserve(base, size) < 0) { - base = -EBUSY; + ret = -EBUSY; goto err; } } else { @@ -266,7 +234,7 @@ int __init dma_declare_contiguous(struct device *dev, phys_addr_t size, */ phys_addr_t addr = __memblock_alloc_base(size, alignment, limit); if (!addr) { - base = -ENOMEM; + ret = -ENOMEM; goto err; } else { base = addr; @@ -277,10 +245,11 @@ int __init dma_declare_contiguous(struct device *dev, phys_addr_t size, * Each reserved area must be initialised later, when more kernel * subsystems (like slab allocator) are available. */ - r->start = base; - r->size = size; - r->dev = dev; - cma_reserved_count++; + cma->base_pfn = PFN_DOWN(base); + cma->count = size >> PAGE_SHIFT; + *res_cma = cma; + cma_area_count++; + pr_info("CMA: reserved %ld MiB at %08lx\n", (unsigned long)size / SZ_1M, (unsigned long)base); @@ -289,7 +258,7 @@ int __init dma_declare_contiguous(struct device *dev, phys_addr_t size, return 0; err: pr_err("CMA: failed to reserve %ld MiB\n", (unsigned long)size / SZ_1M); - return base; + return ret; } /** diff --git a/include/asm-generic/dma-contiguous.h b/include/asm-generic/dma-contiguous.h deleted file mode 100644 index 294b1e755ab2..000000000000 --- a/include/asm-generic/dma-contiguous.h +++ /dev/null @@ -1,28 +0,0 @@ -#ifndef ASM_DMA_CONTIGUOUS_H -#define ASM_DMA_CONTIGUOUS_H - -#ifdef __KERNEL__ -#ifdef CONFIG_CMA - -#include -#include - -static inline struct cma *dev_get_cma_area(struct device *dev) -{ - if (dev && dev->cma_area) - return dev->cma_area; - return dma_contiguous_default_area; -} - -static inline void dev_set_cma_area(struct device *dev, struct cma *cma) -{ - if (dev) - dev->cma_area = cma; - if (!dev && !dma_contiguous_default_area) - dma_contiguous_default_area = cma; -} - -#endif -#endif - -#endif diff --git a/include/linux/device.h b/include/linux/device.h index bcf8c0d4cd98..9200cfd75f15 100644 --- a/include/linux/device.h +++ b/include/linux/device.h @@ -711,7 +711,7 @@ struct device { struct dma_coherent_mem *dma_mem; /* internal for coherent mem override */ -#ifdef CONFIG_CMA +#ifdef CONFIG_DMA_CMA struct cma *cma_area; /* contiguous memory area for dma allocations */ #endif diff --git a/include/linux/dma-contiguous.h b/include/linux/dma-contiguous.h index 00141d3325fe..3b28f937d959 100644 --- a/include/linux/dma-contiguous.h +++ b/include/linux/dma-contiguous.h @@ -67,9 +67,53 @@ struct device; extern struct cma *dma_contiguous_default_area; +static inline struct cma *dev_get_cma_area(struct device *dev) +{ + if (dev && dev->cma_area) + return dev->cma_area; + return dma_contiguous_default_area; +} + +static inline void dev_set_cma_area(struct device *dev, struct cma *cma) +{ + if (dev) + dev->cma_area = cma; +} + +static inline void dma_contiguous_set_default(struct cma *cma) +{ + dma_contiguous_default_area = cma; +} + void dma_contiguous_reserve(phys_addr_t addr_limit); -int dma_declare_contiguous(struct device *dev, phys_addr_t size, - phys_addr_t base, phys_addr_t limit); + +int __init dma_contiguous_reserve_area(phys_addr_t size, phys_addr_t base, + phys_addr_t limit, struct cma **res_cma); + +/** + * dma_declare_contiguous() - reserve area for contiguous memory handling + * for particular device + * @dev: Pointer to device structure. + * @size: Size of the reserved memory. + * @base: Start address of the reserved memory (optional, 0 for any). + * @limit: End address of the reserved memory (optional, 0 for any). + * + * This function reserves memory for specified device. It should be + * called by board specific code when early allocator (memblock or bootmem) + * is still activate. + */ + +static inline int dma_declare_contiguous(struct device *dev, phys_addr_t size, + phys_addr_t base, phys_addr_t limit) +{ + struct cma *cma; + int ret; + ret = dma_contiguous_reserve_area(size, base, limit, &cma); + if (ret == 0) + dev_set_cma_area(dev, cma); + + return ret; +} struct page *dma_alloc_from_contiguous(struct device *dev, int count, unsigned int order); @@ -80,8 +124,22 @@ bool dma_release_from_contiguous(struct device *dev, struct page *pages, #define MAX_CMA_AREAS (0) +static inline struct cma *dev_get_cma_area(struct device *dev) +{ + return NULL; +} + +static inline void dev_set_cma_area(struct device *dev, struct cma *cma) { } + +static inline void dma_contiguous_set_default(struct cma *cma) { } + static inline void dma_contiguous_reserve(phys_addr_t limit) { } +static inline int dma_contiguous_reserve_area(phys_addr_t size, phys_addr_t base, + phys_addr_t limit, struct cma **res_cma) { + return -ENOSYS; +} + static inline int dma_declare_contiguous(struct device *dev, phys_addr_t size, phys_addr_t base, phys_addr_t limit) -- 2.30.2