diff options
Diffstat (limited to 'drivers/base/dma-contiguous.c')
| -rw-r--r-- | drivers/base/dma-contiguous.c | 390 |
1 files changed, 0 insertions, 390 deletions
diff --git a/drivers/base/dma-contiguous.c b/drivers/base/dma-contiguous.c deleted file mode 100644 index 0ca54421ce97..000000000000 --- a/drivers/base/dma-contiguous.c +++ /dev/null @@ -1,390 +0,0 @@ -/* - * Contiguous Memory Allocator for DMA mapping framework - * Copyright (c) 2010-2011 by Samsung Electronics. - * Written by: - * Marek Szyprowski <m.szyprowski@samsung.com> - * Michal Nazarewicz <mina86@mina86.com> - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License as - * published by the Free Software Foundation; either version 2 of the - * License or (at your optional) any later version of the license. - */ - -#define pr_fmt(fmt) "cma: " fmt - -#ifdef CONFIG_CMA_DEBUG -#ifndef DEBUG -# define DEBUG -#endif -#endif - -#include <asm/page.h> -#include <asm/dma-contiguous.h> - -#include <linux/memblock.h> -#include <linux/err.h> -#include <linux/mm.h> -#include <linux/mutex.h> -#include <linux/page-isolation.h> -#include <linux/sizes.h> -#include <linux/slab.h> -#include <linux/swap.h> -#include <linux/mm_types.h> -#include <linux/dma-contiguous.h> - -struct cma { - unsigned long base_pfn; - unsigned long count; - unsigned long *bitmap; -}; - -struct cma *dma_contiguous_default_area; - -#ifdef CONFIG_CMA_SIZE_MBYTES -#define CMA_SIZE_MBYTES CONFIG_CMA_SIZE_MBYTES -#else -#define CMA_SIZE_MBYTES 0 -#endif - -/* - * Default global CMA area size can be defined in kernel's .config. - * This is usefull mainly for distro maintainers to create a kernel - * that works correctly for most supported systems. - * The size can be set in bytes or as a percentage of the total memory - * in the system. - * - * Users, who want to set the size of global CMA area for their system - * should use cma= kernel parameter. - */ -static const phys_addr_t size_bytes = CMA_SIZE_MBYTES * SZ_1M; -static phys_addr_t size_cmdline = -1; - -static int __init early_cma(char *p) -{ - pr_debug("%s(%s)\n", __func__, p); - size_cmdline = memparse(p, &p); - return 0; -} -early_param("cma", early_cma); - -#ifdef CONFIG_CMA_SIZE_PERCENTAGE - -static phys_addr_t __init __maybe_unused cma_early_percent_memory(void) -{ - struct memblock_region *reg; - unsigned long total_pages = 0; - - /* - * We cannot use memblock_phys_mem_size() here, because - * memblock_analyze() has not been called yet. - */ - for_each_memblock(memory, reg) - total_pages += memblock_region_memory_end_pfn(reg) - - memblock_region_memory_base_pfn(reg); - - return (total_pages * CONFIG_CMA_SIZE_PERCENTAGE / 100) << PAGE_SHIFT; -} - -#else - -static inline __maybe_unused phys_addr_t cma_early_percent_memory(void) -{ - return 0; -} - -#endif - -/** - * dma_contiguous_reserve() - reserve area 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 - * called by arch specific code once the early allocator (memblock or bootmem) - * has been activated and all other subsystems have already allocated/reserved - * memory. - */ -void __init dma_contiguous_reserve(phys_addr_t limit) -{ - phys_addr_t selected_size = 0; - - pr_debug("%s(limit %08lx)\n", __func__, (unsigned long)limit); - - if (size_cmdline != -1) { - selected_size = size_cmdline; - } else { -#ifdef CONFIG_CMA_SIZE_SEL_MBYTES - selected_size = size_bytes; -#elif defined(CONFIG_CMA_SIZE_SEL_PERCENTAGE) - selected_size = cma_early_percent_memory(); -#elif defined(CONFIG_CMA_SIZE_SEL_MIN) - selected_size = min(size_bytes, cma_early_percent_memory()); -#elif defined(CONFIG_CMA_SIZE_SEL_MAX) - selected_size = max(size_bytes, cma_early_percent_memory()); -#endif - } - - if (selected_size) { - 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); - } -}; - -static DEFINE_MUTEX(cma_mutex); - -static __init int cma_activate_area(unsigned long base_pfn, unsigned long count) -{ - unsigned long pfn = base_pfn; - unsigned i = count >> pageblock_order; - struct zone *zone; - - WARN_ON_ONCE(!pfn_valid(pfn)); - zone = page_zone(pfn_to_page(pfn)); - - do { - unsigned j; - base_pfn = pfn; - for (j = pageblock_nr_pages; j; --j, pfn++) { - WARN_ON_ONCE(!pfn_valid(pfn)); - if (page_zone(pfn_to_page(pfn)) != zone) - return -EINVAL; - } - 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); -} - -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 int __init cma_init_reserved_areas(void) -{ - struct cma_reserved *r = cma_reserved; - unsigned i = cma_reserved_count; - - pr_debug("%s()\n", __func__); - - 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); - } - 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). - * @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. - */ -int __init dma_declare_contiguous(struct device *dev, phys_addr_t size, - phys_addr_t base, phys_addr_t limit) -{ - struct cma_reserved *r = &cma_reserved[cma_reserved_count]; - phys_addr_t alignment; - - 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)) { - pr_err("Not enough slots for CMA reserved regions!\n"); - return -ENOSPC; - } - - if (!size) - return -EINVAL; - - /* Sanitise input arguments */ - alignment = PAGE_SIZE << max(MAX_ORDER - 1, pageblock_order); - base = ALIGN(base, alignment); - size = ALIGN(size, alignment); - limit &= ~(alignment - 1); - - /* Reserve memory */ - if (base) { - if (memblock_is_region_reserved(base, size) || - memblock_reserve(base, size) < 0) { - base = -EBUSY; - goto err; - } - } else { - /* - * Use __memblock_alloc_base() since - * memblock_alloc_base() panic()s. - */ - phys_addr_t addr = __memblock_alloc_base(size, alignment, limit); - if (!addr) { - base = -ENOMEM; - goto err; - } else { - base = addr; - } - } - - /* - * 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++; - pr_info("CMA: reserved %ld MiB at %08lx\n", (unsigned long)size / SZ_1M, - (unsigned long)base); - - /* Architecture specific contiguous memory fixup. */ - dma_contiguous_early_fixup(base, size); - return 0; -err: - pr_err("CMA: failed to reserve %ld MiB\n", (unsigned long)size / SZ_1M); - return base; -} - -/** - * dma_alloc_from_contiguous() - allocate pages from contiguous area - * @dev: Pointer to device for which the allocation is performed. - * @count: Requested number of pages. - * @align: Requested alignment of pages (in PAGE_SIZE order). - * - * This function allocates memory buffer for specified device. It uses - * device specific contiguous memory area if available or the default - * global one. Requires architecture specific get_dev_cma_area() helper - * function. - */ -struct page *dma_alloc_from_contiguous(struct device *dev, int count, - unsigned int align) -{ - unsigned long mask, pfn, pageno, start = 0; - struct cma *cma = dev_get_cma_area(dev); - struct page *page = NULL; - int ret; - - if (!cma || !cma->count) - return NULL; - - if (align > CONFIG_CMA_ALIGNMENT) - align = CONFIG_CMA_ALIGNMENT; - - pr_debug("%s(cma %p, count %d, align %d)\n", __func__, (void *)cma, - count, align); - - if (!count) - return NULL; - - mask = (1 << align) - 1; - - mutex_lock(&cma_mutex); - - for (;;) { - pageno = bitmap_find_next_zero_area(cma->bitmap, cma->count, - start, count, mask); - if (pageno >= cma->count) - break; - - pfn = cma->base_pfn + pageno; - ret = alloc_contig_range(pfn, pfn + count, MIGRATE_CMA); - if (ret == 0) { - bitmap_set(cma->bitmap, pageno, count); - page = pfn_to_page(pfn); - break; - } else if (ret != -EBUSY) { - break; - } - pr_debug("%s(): memory range at %p is busy, retrying\n", - __func__, pfn_to_page(pfn)); - /* try again with a bit different memory target */ - start = pageno + mask + 1; - } - - mutex_unlock(&cma_mutex); - pr_debug("%s(): returned %p\n", __func__, page); - return page; -} - -/** - * dma_release_from_contiguous() - release allocated pages - * @dev: Pointer to device for which the pages were allocated. - * @pages: Allocated pages. - * @count: Number of allocated pages. - * - * This function releases memory allocated by dma_alloc_from_contiguous(). - * It returns false when provided pages do not belong to contiguous area and - * true otherwise. - */ -bool dma_release_from_contiguous(struct device *dev, struct page *pages, - int count) -{ - struct cma *cma = dev_get_cma_area(dev); - unsigned long pfn; - - if (!cma || !pages) - return false; - - pr_debug("%s(page %p)\n", __func__, (void *)pages); - - pfn = page_to_pfn(pages); - - if (pfn < cma->base_pfn || pfn >= cma->base_pfn + cma->count) - return false; - - VM_BUG_ON(pfn + count > cma->base_pfn + cma->count); - - mutex_lock(&cma_mutex); - bitmap_clear(cma->bitmap, pfn - cma->base_pfn, count); - free_contig_range(pfn, count); - mutex_unlock(&cma_mutex); - - return true; -} |