diff options
Diffstat (limited to 'mm/cma.c')
-rw-r--r-- | mm/cma.c | 333 |
1 files changed, 0 insertions, 333 deletions
diff --git a/mm/cma.c b/mm/cma.c deleted file mode 100644 index 656004216953..000000000000 --- a/mm/cma.c +++ /dev/null @@ -1,333 +0,0 @@ -/* - * Contiguous Memory Allocator - * - * Copyright (c) 2010-2011 by Samsung Electronics. - * Copyright IBM Corporation, 2013 - * Copyright LG Electronics Inc., 2014 - * Written by: - * Marek Szyprowski <m.szyprowski@samsung.com> - * Michal Nazarewicz <mina86@mina86.com> - * Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> - * Joonsoo Kim <iamjoonsoo.kim@lge.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 <linux/memblock.h> -#include <linux/err.h> -#include <linux/mm.h> -#include <linux/mutex.h> -#include <linux/sizes.h> -#include <linux/slab.h> -#include <linux/log2.h> -#include <linux/cma.h> - -struct cma { - unsigned long base_pfn; - unsigned long count; - unsigned long *bitmap; - unsigned int order_per_bit; /* Order of pages represented by one bit */ - struct mutex lock; -}; - -static struct cma cma_areas[MAX_CMA_AREAS]; -static unsigned cma_area_count; -static DEFINE_MUTEX(cma_mutex); - -phys_addr_t cma_get_base(struct cma *cma) -{ - return PFN_PHYS(cma->base_pfn); -} - -unsigned long cma_get_size(struct cma *cma) -{ - return cma->count << PAGE_SHIFT; -} - -static unsigned long cma_bitmap_aligned_mask(struct cma *cma, int align_order) -{ - return (1UL << (align_order >> cma->order_per_bit)) - 1; -} - -static unsigned long cma_bitmap_maxno(struct cma *cma) -{ - return cma->count >> cma->order_per_bit; -} - -static unsigned long cma_bitmap_pages_to_bits(struct cma *cma, - unsigned long pages) -{ - return ALIGN(pages, 1UL << cma->order_per_bit) >> cma->order_per_bit; -} - -static void cma_clear_bitmap(struct cma *cma, unsigned long pfn, int count) -{ - unsigned long bitmap_no, bitmap_count; - - bitmap_no = (pfn - cma->base_pfn) >> cma->order_per_bit; - bitmap_count = cma_bitmap_pages_to_bits(cma, count); - - mutex_lock(&cma->lock); - bitmap_clear(cma->bitmap, bitmap_no, bitmap_count); - mutex_unlock(&cma->lock); -} - -static int __init cma_activate_area(struct cma *cma) -{ - int bitmap_size = BITS_TO_LONGS(cma_bitmap_maxno(cma)) * 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)); - - do { - unsigned j; - - base_pfn = pfn; - for (j = pageblock_nr_pages; j; --j, pfn++) { - WARN_ON_ONCE(!pfn_valid(pfn)); - /* - * alloc_contig_range requires the pfn range - * specified to be in the same zone. Make this - * simple by forcing the entire CMA resv range - * to be in the same zone. - */ - if (page_zone(pfn_to_page(pfn)) != zone) - goto err; - } - init_cma_reserved_pageblock(pfn_to_page(base_pfn)); - } while (--i); - - mutex_init(&cma->lock); - return 0; - -err: - kfree(cma->bitmap); - return -EINVAL; -} - -static int __init cma_init_reserved_areas(void) -{ - int i; - - 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); - -/** - * cma_declare_contiguous() - 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). - * @alignment: Alignment for the CMA area, should be power of 2 or zero - * @order_per_bit: Order of pages represented by one bit on bitmap. - * @res_cma: Pointer to store the created cma region. - * @fixed: hint about where to place the reserved area - * - * 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. - * - * If @fixed is true, reserve contiguous area at exactly @base. If false, - * reserve in range from @base to @limit. - */ -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, - struct cma **res_cma, bool fixed) -{ - struct cma *cma = &cma_areas[cma_area_count]; - int ret = 0; - - 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; - } - - if (!size) - return -EINVAL; - - if (alignment && !is_power_of_2(alignment)) - return -EINVAL; - - /* - * Sanitise input arguments. - * Pages both ends in CMA area could be merged into adjacent unmovable - * migratetype page by page allocator's buddy algorithm. In the case, - * you couldn't get a contiguous memory, which is not what we want. - */ - alignment = max(alignment, - (phys_addr_t)PAGE_SIZE << max(MAX_ORDER - 1, pageblock_order)); - base = ALIGN(base, alignment); - size = ALIGN(size, alignment); - limit &= ~(alignment - 1); - - /* size should be aligned with order_per_bit */ - if (!IS_ALIGNED(size >> PAGE_SHIFT, 1 << order_per_bit)) - return -EINVAL; - - /* Reserve memory */ - if (base && fixed) { - if (memblock_is_region_reserved(base, size) || - memblock_reserve(base, size) < 0) { - ret = -EBUSY; - goto err; - } - } else { - phys_addr_t addr = memblock_alloc_range(size, alignment, base, - limit); - if (!addr) { - ret = -ENOMEM; - goto err; - } else { - base = addr; - } - } - - /* - * Each reserved area must be initialised later, when more kernel - * subsystems (like slab allocator) are available. - */ - cma->base_pfn = PFN_DOWN(base); - cma->count = size >> PAGE_SHIFT; - cma->order_per_bit = order_per_bit; - *res_cma = cma; - cma_area_count++; - - pr_info("CMA: reserved %ld MiB at %08lx\n", (unsigned long)size / SZ_1M, - (unsigned long)base); - return 0; - -err: - pr_err("CMA: failed to reserve %ld MiB\n", (unsigned long)size / SZ_1M); - return ret; -} - -/** - * cma_alloc() - allocate pages from contiguous area - * @cma: Contiguous memory region for which the allocation is performed. - * @count: Requested number of pages. - * @align: Requested alignment of pages (in PAGE_SIZE order). - * - * This function allocates part of contiguous memory on specific - * contiguous memory area. - */ -struct page *cma_alloc(struct cma *cma, int count, unsigned int align) -{ - unsigned long mask, pfn, start = 0; - unsigned long bitmap_maxno, bitmap_no, bitmap_count; - struct page *page = NULL; - int ret; - - if (!cma || !cma->count) - return NULL; - - pr_debug("%s(cma %p, count %d, align %d)\n", __func__, (void *)cma, - count, align); - - if (!count) - return NULL; - - mask = cma_bitmap_aligned_mask(cma, align); - bitmap_maxno = cma_bitmap_maxno(cma); - bitmap_count = cma_bitmap_pages_to_bits(cma, count); - - for (;;) { - mutex_lock(&cma->lock); - bitmap_no = bitmap_find_next_zero_area(cma->bitmap, - bitmap_maxno, start, bitmap_count, mask); - if (bitmap_no >= bitmap_maxno) { - mutex_unlock(&cma->lock); - break; - } - bitmap_set(cma->bitmap, bitmap_no, bitmap_count); - /* - * It's safe to drop the lock here. We've marked this region for - * our exclusive use. If the migration fails we will take the - * lock again and unmark it. - */ - mutex_unlock(&cma->lock); - - pfn = cma->base_pfn + (bitmap_no << cma->order_per_bit); - mutex_lock(&cma_mutex); - ret = alloc_contig_range(pfn, pfn + count, MIGRATE_CMA); - mutex_unlock(&cma_mutex); - if (ret == 0) { - page = pfn_to_page(pfn); - break; - } else if (ret != -EBUSY) { - cma_clear_bitmap(cma, pfn, count); - break; - } - cma_clear_bitmap(cma, pfn, count); - 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 = bitmap_no + mask + 1; - } - - pr_debug("%s(): returned %p\n", __func__, page); - return page; -} - -/** - * cma_release() - release allocated pages - * @cma: Contiguous memory region for which the allocation is performed. - * @pages: Allocated pages. - * @count: Number of allocated pages. - * - * This function releases memory allocated by alloc_cma(). - * It returns false when provided pages do not belong to contiguous area and - * true otherwise. - */ -bool cma_release(struct cma *cma, struct page *pages, int count) -{ - 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); - - free_contig_range(pfn, count); - cma_clear_bitmap(cma, pfn, count); - - return true; -} |