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-rw-r--r--mm/cma.c333
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;
-}