diff options
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/dma/Kconfig | 6 | ||||
| -rw-r--r-- | kernel/dma/Makefile | 1 | ||||
| -rw-r--r-- | kernel/dma/contiguous.c | 4 | ||||
| -rw-r--r-- | kernel/dma/debug.c | 2 | ||||
| -rw-r--r-- | kernel/dma/direct.c | 56 | ||||
| -rw-r--r-- | kernel/dma/pool.c | 264 | ||||
| -rw-r--r-- | kernel/dma/remap.c | 121 |
7 files changed, 318 insertions, 136 deletions
diff --git a/kernel/dma/Kconfig b/kernel/dma/Kconfig index 4c103a24e380..d006668c0027 100644 --- a/kernel/dma/Kconfig +++ b/kernel/dma/Kconfig @@ -79,10 +79,14 @@ config DMA_REMAP select DMA_NONCOHERENT_MMAP bool -config DMA_DIRECT_REMAP +config DMA_COHERENT_POOL bool select DMA_REMAP +config DMA_DIRECT_REMAP + bool + select DMA_COHERENT_POOL + config DMA_CMA bool "DMA Contiguous Memory Allocator" depends on HAVE_DMA_CONTIGUOUS && CMA diff --git a/kernel/dma/Makefile b/kernel/dma/Makefile index d237cf3dc181..370f63344e9c 100644 --- a/kernel/dma/Makefile +++ b/kernel/dma/Makefile @@ -6,4 +6,5 @@ obj-$(CONFIG_DMA_DECLARE_COHERENT) += coherent.o obj-$(CONFIG_DMA_VIRT_OPS) += virt.o obj-$(CONFIG_DMA_API_DEBUG) += debug.o obj-$(CONFIG_SWIOTLB) += swiotlb.o +obj-$(CONFIG_DMA_COHERENT_POOL) += pool.o obj-$(CONFIG_DMA_REMAP) += remap.o diff --git a/kernel/dma/contiguous.c b/kernel/dma/contiguous.c index 8bc6f2d670f9..15bc5026c485 100644 --- a/kernel/dma/contiguous.c +++ b/kernel/dma/contiguous.c @@ -222,8 +222,8 @@ bool dma_release_from_contiguous(struct device *dev, struct page *pages, * @gfp: Allocation flags. * * This function allocates contiguous memory buffer for specified device. It - * first tries to use device specific contiguous memory area if available or - * the default global one, then tries a fallback allocation of normal pages. + * tries to use device specific contiguous memory area if available, or the + * default global one. * * Note that it byapss one-page size of allocations from the global area as * the addresses within one page are always contiguous, so there is no need diff --git a/kernel/dma/debug.c b/kernel/dma/debug.c index 9e1777c81f55..36c962a86bf2 100644 --- a/kernel/dma/debug.c +++ b/kernel/dma/debug.c @@ -656,7 +656,7 @@ static struct dma_debug_entry *__dma_entry_alloc(void) return entry; } -void __dma_entry_alloc_check_leak(void) +static void __dma_entry_alloc_check_leak(void) { u32 tmp = nr_total_entries % nr_prealloc_entries; diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c index 8f4bbdaf965e..0a4881e59aa7 100644 --- a/kernel/dma/direct.c +++ b/kernel/dma/direct.c @@ -45,8 +45,8 @@ u64 dma_direct_get_required_mask(struct device *dev) return (1ULL << (fls64(max_dma) - 1)) * 2 - 1; } -static gfp_t __dma_direct_optimal_gfp_mask(struct device *dev, u64 dma_mask, - u64 *phys_limit) +gfp_t dma_direct_optimal_gfp_mask(struct device *dev, u64 dma_mask, + u64 *phys_limit) { u64 dma_limit = min_not_zero(dma_mask, dev->bus_dma_limit); @@ -76,6 +76,39 @@ static bool dma_coherent_ok(struct device *dev, phys_addr_t phys, size_t size) min_not_zero(dev->coherent_dma_mask, dev->bus_dma_limit); } +/* + * Decrypting memory is allowed to block, so if this device requires + * unencrypted memory it must come from atomic pools. + */ +static inline bool dma_should_alloc_from_pool(struct device *dev, gfp_t gfp, + unsigned long attrs) +{ + if (!IS_ENABLED(CONFIG_DMA_COHERENT_POOL)) + return false; + if (gfpflags_allow_blocking(gfp)) + return false; + if (force_dma_unencrypted(dev)) + return true; + if (!IS_ENABLED(CONFIG_DMA_DIRECT_REMAP)) + return false; + if (dma_alloc_need_uncached(dev, attrs)) + return true; + return false; +} + +static inline bool dma_should_free_from_pool(struct device *dev, + unsigned long attrs) +{ + if (IS_ENABLED(CONFIG_DMA_COHERENT_POOL)) + return true; + if ((attrs & DMA_ATTR_NO_KERNEL_MAPPING) && + !force_dma_unencrypted(dev)) + return false; + if (IS_ENABLED(CONFIG_DMA_DIRECT_REMAP)) + return true; + return false; +} + struct page *__dma_direct_alloc_pages(struct device *dev, size_t size, gfp_t gfp, unsigned long attrs) { @@ -89,8 +122,8 @@ struct page *__dma_direct_alloc_pages(struct device *dev, size_t size, /* we always manually zero the memory once we are done: */ gfp &= ~__GFP_ZERO; - gfp |= __dma_direct_optimal_gfp_mask(dev, dev->coherent_dma_mask, - &phys_limit); + gfp |= dma_direct_optimal_gfp_mask(dev, dev->coherent_dma_mask, + &phys_limit); page = dma_alloc_contiguous(dev, alloc_size, gfp); if (page && !dma_coherent_ok(dev, page_to_phys(page), size)) { dma_free_contiguous(dev, page, alloc_size); @@ -125,10 +158,8 @@ void *dma_direct_alloc_pages(struct device *dev, size_t size, struct page *page; void *ret; - if (IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) && - dma_alloc_need_uncached(dev, attrs) && - !gfpflags_allow_blocking(gfp)) { - ret = dma_alloc_from_pool(PAGE_ALIGN(size), &page, gfp); + if (dma_should_alloc_from_pool(dev, gfp, attrs)) { + ret = dma_alloc_from_pool(dev, PAGE_ALIGN(size), &page, gfp); if (!ret) return NULL; goto done; @@ -204,6 +235,11 @@ void dma_direct_free_pages(struct device *dev, size_t size, void *cpu_addr, { unsigned int page_order = get_order(size); + /* If cpu_addr is not from an atomic pool, dma_free_from_pool() fails */ + if (dma_should_free_from_pool(dev, attrs) && + dma_free_from_pool(dev, cpu_addr, PAGE_ALIGN(size))) + return; + if ((attrs & DMA_ATTR_NO_KERNEL_MAPPING) && !force_dma_unencrypted(dev)) { /* cpu_addr is a struct page cookie, not a kernel address */ @@ -211,10 +247,6 @@ void dma_direct_free_pages(struct device *dev, size_t size, void *cpu_addr, return; } - if (IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) && - dma_free_from_pool(cpu_addr, PAGE_ALIGN(size))) - return; - if (force_dma_unencrypted(dev)) set_memory_encrypted((unsigned long)cpu_addr, 1 << page_order); diff --git a/kernel/dma/pool.c b/kernel/dma/pool.c new file mode 100644 index 000000000000..35bb51c31fff --- /dev/null +++ b/kernel/dma/pool.c @@ -0,0 +1,264 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2012 ARM Ltd. + * Copyright (C) 2020 Google LLC + */ +#include <linux/debugfs.h> +#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/set_memory.h> +#include <linux/slab.h> +#include <linux/workqueue.h> + +static struct gen_pool *atomic_pool_dma __ro_after_init; +static unsigned long pool_size_dma; +static struct gen_pool *atomic_pool_dma32 __ro_after_init; +static unsigned long pool_size_dma32; +static struct gen_pool *atomic_pool_kernel __ro_after_init; +static unsigned long pool_size_kernel; + +/* Size can be defined by the coherent_pool command line */ +static size_t atomic_pool_size; + +/* Dynamic background expansion when the atomic pool is near capacity */ +static struct work_struct atomic_pool_work; + +static int __init early_coherent_pool(char *p) +{ + atomic_pool_size = memparse(p, &p); + return 0; +} +early_param("coherent_pool", early_coherent_pool); + +static void __init dma_atomic_pool_debugfs_init(void) +{ + struct dentry *root; + + root = debugfs_create_dir("dma_pools", NULL); + if (IS_ERR_OR_NULL(root)) + return; + + debugfs_create_ulong("pool_size_dma", 0400, root, &pool_size_dma); + debugfs_create_ulong("pool_size_dma32", 0400, root, &pool_size_dma32); + debugfs_create_ulong("pool_size_kernel", 0400, root, &pool_size_kernel); +} + +static void dma_atomic_pool_size_add(gfp_t gfp, size_t size) +{ + if (gfp & __GFP_DMA) + pool_size_dma += size; + else if (gfp & __GFP_DMA32) + pool_size_dma32 += size; + else + pool_size_kernel += size; +} + +static int atomic_pool_expand(struct gen_pool *pool, size_t pool_size, + gfp_t gfp) +{ + unsigned int order; + struct page *page; + void *addr; + int ret = -ENOMEM; + + /* Cannot allocate larger than MAX_ORDER-1 */ + order = min(get_order(pool_size), MAX_ORDER-1); + + do { + pool_size = 1 << (PAGE_SHIFT + order); + + if (dev_get_cma_area(NULL)) + page = dma_alloc_from_contiguous(NULL, 1 << order, + order, false); + else + page = alloc_pages(gfp, order); + } while (!page && order-- > 0); + if (!page) + goto out; + + arch_dma_prep_coherent(page, pool_size); + +#ifdef CONFIG_DMA_DIRECT_REMAP + addr = dma_common_contiguous_remap(page, pool_size, + pgprot_dmacoherent(PAGE_KERNEL), + __builtin_return_address(0)); + if (!addr) + goto free_page; +#else + addr = page_to_virt(page); +#endif + /* + * Memory in the atomic DMA pools must be unencrypted, the pools do not + * shrink so no re-encryption occurs in dma_direct_free_pages(). + */ + ret = set_memory_decrypted((unsigned long)page_to_virt(page), + 1 << order); + if (ret) + goto remove_mapping; + ret = gen_pool_add_virt(pool, (unsigned long)addr, page_to_phys(page), + pool_size, NUMA_NO_NODE); + if (ret) + goto encrypt_mapping; + + dma_atomic_pool_size_add(gfp, pool_size); + return 0; + +encrypt_mapping: + ret = set_memory_encrypted((unsigned long)page_to_virt(page), + 1 << order); + if (WARN_ON_ONCE(ret)) { + /* Decrypt succeeded but encrypt failed, purposely leak */ + goto out; + } +remove_mapping: +#ifdef CONFIG_DMA_DIRECT_REMAP + dma_common_free_remap(addr, pool_size); +#endif +free_page: __maybe_unused + if (!dma_release_from_contiguous(NULL, page, 1 << order)) + __free_pages(page, order); +out: + return ret; +} + +static void atomic_pool_resize(struct gen_pool *pool, gfp_t gfp) +{ + if (pool && gen_pool_avail(pool) < atomic_pool_size) + atomic_pool_expand(pool, gen_pool_size(pool), gfp); +} + +static void atomic_pool_work_fn(struct work_struct *work) +{ + if (IS_ENABLED(CONFIG_ZONE_DMA)) + atomic_pool_resize(atomic_pool_dma, + GFP_KERNEL | GFP_DMA); + if (IS_ENABLED(CONFIG_ZONE_DMA32)) + atomic_pool_resize(atomic_pool_dma32, + GFP_KERNEL | GFP_DMA32); + atomic_pool_resize(atomic_pool_kernel, GFP_KERNEL); +} + +static __init struct gen_pool *__dma_atomic_pool_init(size_t pool_size, + gfp_t gfp) +{ + struct gen_pool *pool; + int ret; + + pool = gen_pool_create(PAGE_SHIFT, NUMA_NO_NODE); + if (!pool) + return NULL; + + gen_pool_set_algo(pool, gen_pool_first_fit_order_align, NULL); + + ret = atomic_pool_expand(pool, pool_size, gfp); + if (ret) { + gen_pool_destroy(pool); + pr_err("DMA: failed to allocate %zu KiB %pGg pool for atomic allocation\n", + pool_size >> 10, &gfp); + return NULL; + } + + pr_info("DMA: preallocated %zu KiB %pGg pool for atomic allocations\n", + gen_pool_size(pool) >> 10, &gfp); + return pool; +} + +static int __init dma_atomic_pool_init(void) +{ + int ret = 0; + + /* + * If coherent_pool was not used on the command line, default the pool + * sizes to 128KB per 1GB of memory, min 128KB, max MAX_ORDER-1. + */ + if (!atomic_pool_size) { + atomic_pool_size = max(totalram_pages() >> PAGE_SHIFT, 1UL) * + SZ_128K; + atomic_pool_size = min_t(size_t, atomic_pool_size, + 1 << (PAGE_SHIFT + MAX_ORDER-1)); + } + INIT_WORK(&atomic_pool_work, atomic_pool_work_fn); + + atomic_pool_kernel = __dma_atomic_pool_init(atomic_pool_size, + GFP_KERNEL); + if (!atomic_pool_kernel) + ret = -ENOMEM; + if (IS_ENABLED(CONFIG_ZONE_DMA)) { + atomic_pool_dma = __dma_atomic_pool_init(atomic_pool_size, + GFP_KERNEL | GFP_DMA); + if (!atomic_pool_dma) + ret = -ENOMEM; + } + if (IS_ENABLED(CONFIG_ZONE_DMA32)) { + atomic_pool_dma32 = __dma_atomic_pool_init(atomic_pool_size, + GFP_KERNEL | GFP_DMA32); + if (!atomic_pool_dma32) + ret = -ENOMEM; + } + + dma_atomic_pool_debugfs_init(); + return ret; +} +postcore_initcall(dma_atomic_pool_init); + +static inline struct gen_pool *dev_to_pool(struct device *dev) +{ + u64 phys_mask; + gfp_t gfp; + + gfp = dma_direct_optimal_gfp_mask(dev, dev->coherent_dma_mask, + &phys_mask); + if (IS_ENABLED(CONFIG_ZONE_DMA) && gfp == GFP_DMA) + return atomic_pool_dma; + if (IS_ENABLED(CONFIG_ZONE_DMA32) && gfp == GFP_DMA32) + return atomic_pool_dma32; + return atomic_pool_kernel; +} + +static bool dma_in_atomic_pool(struct device *dev, void *start, size_t size) +{ + struct gen_pool *pool = dev_to_pool(dev); + + if (unlikely(!pool)) + return false; + return gen_pool_has_addr(pool, (unsigned long)start, size); +} + +void *dma_alloc_from_pool(struct device *dev, size_t size, + struct page **ret_page, gfp_t flags) +{ + struct gen_pool *pool = dev_to_pool(dev); + unsigned long val; + void *ptr = NULL; + + if (!pool) { + WARN(1, "%pGg atomic pool not initialised!\n", &flags); + return NULL; + } + + val = gen_pool_alloc(pool, size); + if (val) { + phys_addr_t phys = gen_pool_virt_to_phys(pool, val); + + *ret_page = pfn_to_page(__phys_to_pfn(phys)); + ptr = (void *)val; + memset(ptr, 0, size); + } + if (gen_pool_avail(pool) < atomic_pool_size) + schedule_work(&atomic_pool_work); + + return ptr; +} + +bool dma_free_from_pool(struct device *dev, void *start, size_t size) +{ + struct gen_pool *pool = dev_to_pool(dev); + + if (!dma_in_atomic_pool(dev, start, size)) + return false; + gen_pool_free(pool, (unsigned long)start, size); + return true; +} diff --git a/kernel/dma/remap.c b/kernel/dma/remap.c index 914ff5a58dd5..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> @@ -73,117 +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 */ |