diff options
Diffstat (limited to 'mm')
| -rw-r--r-- | mm/cma.c | 62 |
1 files changed, 51 insertions, 11 deletions
@@ -143,6 +143,54 @@ 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), @@ -165,7 +213,6 @@ 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; phys_addr_t memblock_end = memblock_end_of_DRAM(); phys_addr_t highmem_start = __pa(high_memory); int ret = 0; @@ -237,16 +284,9 @@ int __init cma_declare_contiguous(phys_addr_t base, } } - /* - * 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++; + ret = cma_init_reserved_mem(base, size, order_per_bit, res_cma); + if (ret) + goto err; pr_info("Reserved %ld MiB at %08lx\n", (unsigned long)size / SZ_1M, (unsigned long)base); |