diff options
Diffstat (limited to 'kernel/dma/remap.c')
| -rw-r--r-- | kernel/dma/remap.c | 169 |
1 files changed, 13 insertions, 156 deletions
diff --git a/kernel/dma/remap.c b/kernel/dma/remap.c index d14cbc83986a..e739a6eea6e7 100644 --- a/kernel/dma/remap.c +++ b/kernel/dma/remap.c @@ -1,13 +1,8 @@ // SPDX-License-Identifier: GPL-2.0 /* - * Copyright (C) 2012 ARM Ltd. * Copyright (c) 2014 The Linux Foundation */ -#include <linux/dma-direct.h> -#include <linux/dma-noncoherent.h> -#include <linux/dma-contiguous.h> -#include <linux/init.h> -#include <linux/genalloc.h> +#include <linux/dma-mapping.h> #include <linux/slab.h> #include <linux/vmalloc.h> @@ -20,23 +15,6 @@ struct page **dma_common_find_pages(void *cpu_addr) return area->pages; } -static struct vm_struct *__dma_common_pages_remap(struct page **pages, - size_t size, pgprot_t prot, const void *caller) -{ - struct vm_struct *area; - - area = get_vm_area_caller(size, VM_DMA_COHERENT, caller); - if (!area) - return NULL; - - if (map_vm_area(area, prot, pages)) { - vunmap(area->addr); - return NULL; - } - - return area; -} - /* * Remaps an array of PAGE_SIZE pages into another vm_area. * Cannot be used in non-sleeping contexts @@ -44,15 +22,12 @@ static struct vm_struct *__dma_common_pages_remap(struct page **pages, void *dma_common_pages_remap(struct page **pages, size_t size, pgprot_t prot, const void *caller) { - struct vm_struct *area; - - area = __dma_common_pages_remap(pages, size, prot, caller); - if (!area) - return NULL; + void *vaddr; - area->pages = pages; - - return area->addr; + vaddr = vmap(pages, size >> PAGE_SHIFT, VM_DMA_COHERENT, prot); + if (vaddr) + find_vm_area(vaddr)->pages = pages; + return vaddr; } /* @@ -62,24 +37,20 @@ void *dma_common_pages_remap(struct page **pages, size_t size, void *dma_common_contiguous_remap(struct page *page, size_t size, pgprot_t prot, const void *caller) { - int i; + int count = size >> PAGE_SHIFT; struct page **pages; - struct vm_struct *area; + void *vaddr; + int i; - pages = kmalloc(sizeof(struct page *) << get_order(size), GFP_KERNEL); + pages = kmalloc_array(count, sizeof(struct page *), GFP_KERNEL); if (!pages) return NULL; - - for (i = 0; i < (size >> PAGE_SHIFT); i++) + for (i = 0; i < count; i++) pages[i] = nth_page(page, i); - - area = __dma_common_pages_remap(pages, size, prot, caller); - + vaddr = vmap(pages, count, VM_DMA_COHERENT, prot); kfree(pages); - if (!area) - return NULL; - return area->addr; + return vaddr; } /* @@ -97,117 +68,3 @@ void dma_common_free_remap(void *cpu_addr, size_t size) unmap_kernel_range((unsigned long)cpu_addr, PAGE_ALIGN(size)); vunmap(cpu_addr); } - -#ifdef CONFIG_DMA_DIRECT_REMAP -static struct gen_pool *atomic_pool __ro_after_init; - -#define DEFAULT_DMA_COHERENT_POOL_SIZE SZ_256K -static size_t atomic_pool_size __initdata = DEFAULT_DMA_COHERENT_POOL_SIZE; - -static int __init early_coherent_pool(char *p) -{ - atomic_pool_size = memparse(p, &p); - return 0; -} -early_param("coherent_pool", early_coherent_pool); - -static gfp_t dma_atomic_pool_gfp(void) -{ - if (IS_ENABLED(CONFIG_ZONE_DMA)) - return GFP_DMA; - if (IS_ENABLED(CONFIG_ZONE_DMA32)) - return GFP_DMA32; - return GFP_KERNEL; -} - -static int __init dma_atomic_pool_init(void) -{ - unsigned int pool_size_order = get_order(atomic_pool_size); - unsigned long nr_pages = atomic_pool_size >> PAGE_SHIFT; - struct page *page; - void *addr; - int ret; - - if (dev_get_cma_area(NULL)) - page = dma_alloc_from_contiguous(NULL, nr_pages, - pool_size_order, false); - else - page = alloc_pages(dma_atomic_pool_gfp(), pool_size_order); - if (!page) - goto out; - - arch_dma_prep_coherent(page, atomic_pool_size); - - atomic_pool = gen_pool_create(PAGE_SHIFT, -1); - if (!atomic_pool) - goto free_page; - - addr = dma_common_contiguous_remap(page, atomic_pool_size, - pgprot_dmacoherent(PAGE_KERNEL), - __builtin_return_address(0)); - if (!addr) - goto destroy_genpool; - - ret = gen_pool_add_virt(atomic_pool, (unsigned long)addr, - page_to_phys(page), atomic_pool_size, -1); - if (ret) - goto remove_mapping; - gen_pool_set_algo(atomic_pool, gen_pool_first_fit_order_align, NULL); - - pr_info("DMA: preallocated %zu KiB pool for atomic allocations\n", - atomic_pool_size / 1024); - return 0; - -remove_mapping: - dma_common_free_remap(addr, atomic_pool_size); -destroy_genpool: - gen_pool_destroy(atomic_pool); - atomic_pool = NULL; -free_page: - if (!dma_release_from_contiguous(NULL, page, nr_pages)) - __free_pages(page, pool_size_order); -out: - pr_err("DMA: failed to allocate %zu KiB pool for atomic coherent allocation\n", - atomic_pool_size / 1024); - return -ENOMEM; -} -postcore_initcall(dma_atomic_pool_init); - -bool dma_in_atomic_pool(void *start, size_t size) -{ - if (unlikely(!atomic_pool)) - return false; - - return gen_pool_has_addr(atomic_pool, (unsigned long)start, size); -} - -void *dma_alloc_from_pool(size_t size, struct page **ret_page, gfp_t flags) -{ - unsigned long val; - void *ptr = NULL; - - if (!atomic_pool) { - WARN(1, "coherent pool not initialised!\n"); - return NULL; - } - - val = gen_pool_alloc(atomic_pool, size); - if (val) { - phys_addr_t phys = gen_pool_virt_to_phys(atomic_pool, val); - - *ret_page = pfn_to_page(__phys_to_pfn(phys)); - ptr = (void *)val; - memset(ptr, 0, size); - } - - return ptr; -} - -bool dma_free_from_pool(void *start, size_t size) -{ - if (!dma_in_atomic_pool(start, size)) - return false; - gen_pool_free(atomic_pool, (unsigned long)start, size); - return true; -} -#endif /* CONFIG_DMA_DIRECT_REMAP */ |