1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * This header is for implementations of dma_map_ops and related code. 4 * It should not be included in drivers just using the DMA API. 5 */ 6 #ifndef _LINUX_DMA_MAP_OPS_H 7 #define _LINUX_DMA_MAP_OPS_H 8 9 #include <linux/dma-mapping.h> 10 #include <linux/pgtable.h> 11 #include <linux/slab.h> 12 13 struct cma; 14 struct iommu_ops; 15 16 struct dma_map_ops { 17 void *(*alloc)(struct device *dev, size_t size, 18 dma_addr_t *dma_handle, gfp_t gfp, 19 unsigned long attrs); 20 void (*free)(struct device *dev, size_t size, void *vaddr, 21 dma_addr_t dma_handle, unsigned long attrs); 22 struct page *(*alloc_pages_op)(struct device *dev, size_t size, 23 dma_addr_t *dma_handle, enum dma_data_direction dir, 24 gfp_t gfp); 25 void (*free_pages)(struct device *dev, size_t size, struct page *vaddr, 26 dma_addr_t dma_handle, enum dma_data_direction dir); 27 int (*mmap)(struct device *, struct vm_area_struct *, 28 void *, dma_addr_t, size_t, unsigned long attrs); 29 30 int (*get_sgtable)(struct device *dev, struct sg_table *sgt, 31 void *cpu_addr, dma_addr_t dma_addr, size_t size, 32 unsigned long attrs); 33 34 dma_addr_t (*map_phys)(struct device *dev, phys_addr_t phys, 35 size_t size, enum dma_data_direction dir, 36 unsigned long attrs); 37 void (*unmap_phys)(struct device *dev, dma_addr_t dma_handle, 38 size_t size, enum dma_data_direction dir, 39 unsigned long attrs); 40 /* 41 * map_sg should return a negative error code on error. See 42 * dma_map_sgtable() for a list of appropriate error codes 43 * and their meanings. 44 */ 45 int (*map_sg)(struct device *dev, struct scatterlist *sg, int nents, 46 enum dma_data_direction dir, unsigned long attrs); 47 void (*unmap_sg)(struct device *dev, struct scatterlist *sg, int nents, 48 enum dma_data_direction dir, unsigned long attrs); 49 void (*sync_single_for_cpu)(struct device *dev, dma_addr_t dma_handle, 50 size_t size, enum dma_data_direction dir); 51 void (*sync_single_for_device)(struct device *dev, 52 dma_addr_t dma_handle, size_t size, 53 enum dma_data_direction dir); 54 void (*sync_sg_for_cpu)(struct device *dev, struct scatterlist *sg, 55 int nents, enum dma_data_direction dir); 56 void (*sync_sg_for_device)(struct device *dev, struct scatterlist *sg, 57 int nents, enum dma_data_direction dir); 58 void (*cache_sync)(struct device *dev, void *vaddr, size_t size, 59 enum dma_data_direction direction); 60 int (*dma_supported)(struct device *dev, u64 mask); 61 u64 (*get_required_mask)(struct device *dev); 62 size_t (*max_mapping_size)(struct device *dev); 63 size_t (*max_opt_mapping_size)(void); 64 unsigned long (*get_merge_boundary)(struct device *dev); 65 }; 66 67 #ifdef CONFIG_ARCH_HAS_DMA_OPS 68 #include <asm/dma-mapping.h> 69 70 static inline const struct dma_map_ops *get_dma_ops(struct device *dev) 71 { 72 if (dev->dma_ops) 73 return dev->dma_ops; 74 return get_arch_dma_ops(); 75 } 76 77 static inline void set_dma_ops(struct device *dev, 78 const struct dma_map_ops *dma_ops) 79 { 80 dev->dma_ops = dma_ops; 81 } 82 #else /* CONFIG_ARCH_HAS_DMA_OPS */ 83 static inline const struct dma_map_ops *get_dma_ops(struct device *dev) 84 { 85 return NULL; 86 } 87 static inline void set_dma_ops(struct device *dev, 88 const struct dma_map_ops *dma_ops) 89 { 90 } 91 #endif /* CONFIG_ARCH_HAS_DMA_OPS */ 92 93 #ifdef CONFIG_DMA_CMA 94 struct cma *dev_get_cma_area(struct device *dev); 95 struct cma *dma_contiguous_get_area_by_idx(unsigned int idx); 96 97 void dma_contiguous_reserve(phys_addr_t addr_limit); 98 int __init dma_contiguous_reserve_area(phys_addr_t size, phys_addr_t base, 99 phys_addr_t limit, struct cma **res_cma, bool fixed); 100 101 struct page *dma_alloc_from_contiguous(struct device *dev, size_t count, 102 unsigned int order, bool no_warn); 103 bool dma_release_from_contiguous(struct device *dev, struct page *pages, 104 int count); 105 struct page *dma_alloc_contiguous(struct device *dev, size_t size, gfp_t gfp); 106 void dma_free_contiguous(struct device *dev, struct page *page, size_t size); 107 108 void dma_contiguous_early_fixup(phys_addr_t base, unsigned long size); 109 #else /* CONFIG_DMA_CMA */ 110 static inline struct cma *dev_get_cma_area(struct device *dev) 111 { 112 return NULL; 113 } 114 static inline struct cma *dma_contiguous_get_area_by_idx(unsigned int idx) 115 { 116 return NULL; 117 } 118 static inline void dma_contiguous_reserve(phys_addr_t limit) 119 { 120 } 121 static inline int dma_contiguous_reserve_area(phys_addr_t size, 122 phys_addr_t base, phys_addr_t limit, struct cma **res_cma, 123 bool fixed) 124 { 125 return -ENOSYS; 126 } 127 static inline struct page *dma_alloc_from_contiguous(struct device *dev, 128 size_t count, unsigned int order, bool no_warn) 129 { 130 return NULL; 131 } 132 static inline bool dma_release_from_contiguous(struct device *dev, 133 struct page *pages, int count) 134 { 135 return false; 136 } 137 /* Use fallback alloc() and free() when CONFIG_DMA_CMA=n */ 138 static inline struct page *dma_alloc_contiguous(struct device *dev, size_t size, 139 gfp_t gfp) 140 { 141 return NULL; 142 } 143 static inline void dma_free_contiguous(struct device *dev, struct page *page, 144 size_t size) 145 { 146 free_pages_exact(page_address(page), size); 147 } 148 #endif /* CONFIG_DMA_CMA*/ 149 150 #ifdef CONFIG_DMA_DECLARE_COHERENT 151 int dma_declare_coherent_memory(struct device *dev, phys_addr_t phys_addr, 152 dma_addr_t device_addr, size_t size); 153 void dma_release_coherent_memory(struct device *dev); 154 int dma_alloc_from_dev_coherent(struct device *dev, ssize_t size, 155 dma_addr_t *dma_handle, void **ret); 156 int dma_release_from_dev_coherent(struct device *dev, int order, void *vaddr); 157 int dma_mmap_from_dev_coherent(struct device *dev, struct vm_area_struct *vma, 158 void *cpu_addr, size_t size, int *ret); 159 #else 160 static inline int dma_declare_coherent_memory(struct device *dev, 161 phys_addr_t phys_addr, dma_addr_t device_addr, size_t size) 162 { 163 return -ENOSYS; 164 } 165 166 #define dma_alloc_from_dev_coherent(dev, size, handle, ret) (0) 167 #define dma_release_from_dev_coherent(dev, order, vaddr) (0) 168 #define dma_mmap_from_dev_coherent(dev, vma, vaddr, order, ret) (0) 169 static inline void dma_release_coherent_memory(struct device *dev) { } 170 #endif /* CONFIG_DMA_DECLARE_COHERENT */ 171 172 #ifdef CONFIG_DMA_GLOBAL_POOL 173 void *dma_alloc_from_global_coherent(struct device *dev, ssize_t size, 174 dma_addr_t *dma_handle); 175 int dma_release_from_global_coherent(int order, void *vaddr); 176 int dma_mmap_from_global_coherent(struct vm_area_struct *vma, void *cpu_addr, 177 size_t size, int *ret); 178 int dma_init_global_coherent(phys_addr_t phys_addr, size_t size); 179 #else 180 static inline void *dma_alloc_from_global_coherent(struct device *dev, 181 ssize_t size, dma_addr_t *dma_handle) 182 { 183 return NULL; 184 } 185 static inline int dma_release_from_global_coherent(int order, void *vaddr) 186 { 187 return 0; 188 } 189 static inline int dma_mmap_from_global_coherent(struct vm_area_struct *vma, 190 void *cpu_addr, size_t size, int *ret) 191 { 192 return 0; 193 } 194 #endif /* CONFIG_DMA_GLOBAL_POOL */ 195 196 int dma_common_get_sgtable(struct device *dev, struct sg_table *sgt, 197 void *cpu_addr, dma_addr_t dma_addr, size_t size, 198 unsigned long attrs); 199 int dma_common_mmap(struct device *dev, struct vm_area_struct *vma, 200 void *cpu_addr, dma_addr_t dma_addr, size_t size, 201 unsigned long attrs); 202 struct page *dma_common_alloc_pages(struct device *dev, size_t size, 203 dma_addr_t *dma_handle, enum dma_data_direction dir, gfp_t gfp); 204 void dma_common_free_pages(struct device *dev, size_t size, struct page *vaddr, 205 dma_addr_t dma_handle, enum dma_data_direction dir); 206 207 struct page **dma_common_find_pages(void *cpu_addr); 208 void *dma_common_contiguous_remap(struct page *page, size_t size, pgprot_t prot, 209 const void *caller); 210 void *dma_common_pages_remap(struct page **pages, size_t size, pgprot_t prot, 211 const void *caller); 212 void dma_common_free_remap(void *cpu_addr, size_t size); 213 214 struct page *dma_alloc_from_pool(struct device *dev, size_t size, 215 void **cpu_addr, gfp_t flags, unsigned long attrs, 216 bool (*phys_addr_ok)(struct device *, phys_addr_t, size_t)); 217 bool dma_free_from_pool(struct device *dev, void *start, size_t size); 218 bool dma_free_from_pool_page(struct device *dev, struct page *page, size_t size); 219 220 int dma_direct_set_offset(struct device *dev, phys_addr_t cpu_start, 221 dma_addr_t dma_start, u64 size); 222 223 #if defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_DEVICE) || \ 224 defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU) || \ 225 defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU_ALL) 226 extern bool dma_default_coherent; 227 static inline bool dev_is_dma_coherent(struct device *dev) 228 { 229 return dev_dma_coherent(dev); 230 } 231 #else 232 #define dma_default_coherent true 233 234 static inline bool dev_is_dma_coherent(struct device *dev) 235 { 236 return true; 237 } 238 #endif 239 240 static inline void dma_reset_need_sync(struct device *dev) 241 { 242 #ifdef CONFIG_DMA_NEED_SYNC 243 /* Reset it only once so that the function can be called on hotpath */ 244 if (unlikely(dev_dma_skip_sync(dev))) 245 dev_clear_dma_skip_sync(dev); 246 #endif 247 } 248 249 /* 250 * Check whether potential kmalloc() buffers are safe for non-coherent DMA. 251 */ 252 static inline bool dma_kmalloc_safe(struct device *dev, 253 enum dma_data_direction dir) 254 { 255 /* 256 * If DMA bouncing of kmalloc() buffers is disabled, the kmalloc() 257 * caches have already been aligned to a DMA-safe size. 258 */ 259 if (!IS_ENABLED(CONFIG_DMA_BOUNCE_UNALIGNED_KMALLOC)) 260 return true; 261 262 /* 263 * kmalloc() buffers are DMA-safe irrespective of size if the device 264 * is coherent or the direction is DMA_TO_DEVICE (non-desctructive 265 * cache maintenance and benign cache line evictions). 266 */ 267 if (dev_is_dma_coherent(dev) || dir == DMA_TO_DEVICE) 268 return true; 269 270 return false; 271 } 272 273 /* 274 * Check whether the given size, assuming it is for a kmalloc()'ed buffer, is 275 * sufficiently aligned for non-coherent DMA. 276 */ 277 static inline bool dma_kmalloc_size_aligned(size_t size) 278 { 279 /* 280 * Larger kmalloc() sizes are guaranteed to be aligned to 281 * ARCH_DMA_MINALIGN. 282 */ 283 if (size >= 2 * ARCH_DMA_MINALIGN || 284 IS_ALIGNED(kmalloc_size_roundup(size), dma_get_cache_alignment())) 285 return true; 286 287 return false; 288 } 289 290 /* 291 * Check whether the given object size may have originated from a kmalloc() 292 * buffer with a slab alignment below the DMA-safe alignment and needs 293 * bouncing for non-coherent DMA. The pointer alignment is not considered and 294 * in-structure DMA-safe offsets are the responsibility of the caller. Such 295 * code should use the static ARCH_DMA_MINALIGN for compiler annotations. 296 * 297 * The heuristics can have false positives, bouncing unnecessarily, though the 298 * buffers would be small. False negatives are theoretically possible if, for 299 * example, multiple small kmalloc() buffers are coalesced into a larger 300 * buffer that passes the alignment check. There are no such known constructs 301 * in the kernel. 302 */ 303 static inline bool dma_kmalloc_needs_bounce(struct device *dev, size_t size, 304 enum dma_data_direction dir) 305 { 306 return !dma_kmalloc_safe(dev, dir) && !dma_kmalloc_size_aligned(size); 307 } 308 309 void *arch_dma_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle, 310 gfp_t gfp, unsigned long attrs); 311 void arch_dma_free(struct device *dev, size_t size, void *cpu_addr, 312 dma_addr_t dma_addr, unsigned long attrs); 313 314 #ifdef CONFIG_ARCH_HAS_DMA_SET_MASK 315 void arch_dma_set_mask(struct device *dev, u64 mask); 316 #else 317 #define arch_dma_set_mask(dev, mask) do { } while (0) 318 #endif 319 320 #ifdef CONFIG_MMU 321 /* 322 * Page protection so that devices that can't snoop CPU caches can use the 323 * memory coherently. We default to pgprot_noncached which is usually used 324 * for ioremap as a safe bet, but architectures can override this with less 325 * strict semantics if possible. 326 */ 327 #ifndef pgprot_dmacoherent 328 #define pgprot_dmacoherent(prot) pgprot_noncached(prot) 329 #endif 330 331 pgprot_t dma_pgprot(struct device *dev, pgprot_t prot, unsigned long attrs); 332 #else 333 static inline pgprot_t dma_pgprot(struct device *dev, pgprot_t prot, 334 unsigned long attrs) 335 { 336 return prot; /* no protection bits supported without page tables */ 337 } 338 #endif /* CONFIG_MMU */ 339 340 #ifdef CONFIG_ARCH_HAS_SYNC_DMA_FOR_DEVICE 341 void arch_sync_dma_for_device(phys_addr_t paddr, size_t size, 342 enum dma_data_direction dir); 343 #else 344 static inline void arch_sync_dma_for_device(phys_addr_t paddr, size_t size, 345 enum dma_data_direction dir) 346 { 347 } 348 #endif /* ARCH_HAS_SYNC_DMA_FOR_DEVICE */ 349 350 #ifdef CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU 351 void arch_sync_dma_for_cpu(phys_addr_t paddr, size_t size, 352 enum dma_data_direction dir); 353 #else 354 static inline void arch_sync_dma_for_cpu(phys_addr_t paddr, size_t size, 355 enum dma_data_direction dir) 356 { 357 } 358 #endif /* ARCH_HAS_SYNC_DMA_FOR_CPU */ 359 360 #ifndef CONFIG_ARCH_HAS_BATCHED_DMA_SYNC 361 static inline void arch_sync_dma_flush(void) 362 { 363 } 364 #endif 365 366 #ifdef CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU_ALL 367 void arch_sync_dma_for_cpu_all(void); 368 #else 369 static inline void arch_sync_dma_for_cpu_all(void) 370 { 371 } 372 #endif /* CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU_ALL */ 373 374 #ifdef CONFIG_ARCH_HAS_DMA_PREP_COHERENT 375 void arch_dma_prep_coherent(struct page *page, size_t size); 376 #else 377 static inline void arch_dma_prep_coherent(struct page *page, size_t size) 378 { 379 } 380 #endif /* CONFIG_ARCH_HAS_DMA_PREP_COHERENT */ 381 382 void *arch_dma_set_uncached(void *addr, size_t size); 383 void arch_dma_clear_uncached(void *addr, size_t size); 384 385 #ifdef CONFIG_ARCH_HAS_DMA_MAP_DIRECT 386 bool arch_dma_map_phys_direct(struct device *dev, phys_addr_t addr); 387 bool arch_dma_unmap_phys_direct(struct device *dev, dma_addr_t dma_handle); 388 bool arch_dma_map_sg_direct(struct device *dev, struct scatterlist *sg, 389 int nents); 390 bool arch_dma_unmap_sg_direct(struct device *dev, struct scatterlist *sg, 391 int nents); 392 bool arch_dma_alloc_direct(struct device *dev); 393 bool arch_dma_free_direct(struct device *dev, dma_addr_t dma_handle); 394 #else 395 #define arch_dma_map_phys_direct(d, a) (false) 396 #define arch_dma_unmap_phys_direct(d, a) (false) 397 #define arch_dma_map_sg_direct(d, s, n) (false) 398 #define arch_dma_unmap_sg_direct(d, s, n) (false) 399 #define arch_dma_alloc_direct(d) (false) 400 #define arch_dma_free_direct(d, a) (false) 401 #endif 402 403 #ifdef CONFIG_ARCH_HAS_SETUP_DMA_OPS 404 void arch_setup_dma_ops(struct device *dev, bool coherent); 405 #else 406 static inline void arch_setup_dma_ops(struct device *dev, bool coherent) 407 { 408 } 409 #endif /* CONFIG_ARCH_HAS_SETUP_DMA_OPS */ 410 411 #ifdef CONFIG_ARCH_HAS_TEARDOWN_DMA_OPS 412 void arch_teardown_dma_ops(struct device *dev); 413 #else 414 static inline void arch_teardown_dma_ops(struct device *dev) 415 { 416 } 417 #endif /* CONFIG_ARCH_HAS_TEARDOWN_DMA_OPS */ 418 419 #ifdef CONFIG_DMA_API_DEBUG 420 void dma_debug_add_bus(const struct bus_type *bus); 421 void debug_dma_dump_mappings(struct device *dev); 422 #else 423 static inline void dma_debug_add_bus(const struct bus_type *bus) 424 { 425 } 426 static inline void debug_dma_dump_mappings(struct device *dev) 427 { 428 } 429 #endif /* CONFIG_DMA_API_DEBUG */ 430 431 extern const struct dma_map_ops dma_dummy_ops; 432 #endif /* _LINUX_DMA_MAP_OPS_H */ 433