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 (*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 extern struct cma *dma_contiguous_default_area; 95 96 static inline struct cma *dev_get_cma_area(struct device *dev) 97 { 98 if (dev && dev->cma_area) 99 return dev->cma_area; 100 return dma_contiguous_default_area; 101 } 102 103 void dma_contiguous_reserve(phys_addr_t addr_limit); 104 int __init dma_contiguous_reserve_area(phys_addr_t size, phys_addr_t base, 105 phys_addr_t limit, struct cma **res_cma, bool fixed); 106 107 struct page *dma_alloc_from_contiguous(struct device *dev, size_t count, 108 unsigned int order, bool no_warn); 109 bool dma_release_from_contiguous(struct device *dev, struct page *pages, 110 int count); 111 struct page *dma_alloc_contiguous(struct device *dev, size_t size, gfp_t gfp); 112 void dma_free_contiguous(struct device *dev, struct page *page, size_t size); 113 114 void dma_contiguous_early_fixup(phys_addr_t base, unsigned long size); 115 #else /* CONFIG_DMA_CMA */ 116 static inline struct cma *dev_get_cma_area(struct device *dev) 117 { 118 return NULL; 119 } 120 static inline void dma_contiguous_reserve(phys_addr_t limit) 121 { 122 } 123 static inline int dma_contiguous_reserve_area(phys_addr_t size, 124 phys_addr_t base, phys_addr_t limit, struct cma **res_cma, 125 bool fixed) 126 { 127 return -ENOSYS; 128 } 129 static inline struct page *dma_alloc_from_contiguous(struct device *dev, 130 size_t count, unsigned int order, bool no_warn) 131 { 132 return NULL; 133 } 134 static inline bool dma_release_from_contiguous(struct device *dev, 135 struct page *pages, int count) 136 { 137 return false; 138 } 139 /* Use fallback alloc() and free() when CONFIG_DMA_CMA=n */ 140 static inline struct page *dma_alloc_contiguous(struct device *dev, size_t size, 141 gfp_t gfp) 142 { 143 return NULL; 144 } 145 static inline void dma_free_contiguous(struct device *dev, struct page *page, 146 size_t size) 147 { 148 __free_pages(page, get_order(size)); 149 } 150 static inline void dma_contiguous_early_fixup(phys_addr_t base, unsigned long size) 151 { 152 } 153 #endif /* CONFIG_DMA_CMA*/ 154 155 #ifdef CONFIG_DMA_DECLARE_COHERENT 156 int dma_declare_coherent_memory(struct device *dev, phys_addr_t phys_addr, 157 dma_addr_t device_addr, size_t size); 158 void dma_release_coherent_memory(struct device *dev); 159 int dma_alloc_from_dev_coherent(struct device *dev, ssize_t size, 160 dma_addr_t *dma_handle, void **ret); 161 int dma_release_from_dev_coherent(struct device *dev, int order, void *vaddr); 162 int dma_mmap_from_dev_coherent(struct device *dev, struct vm_area_struct *vma, 163 void *cpu_addr, size_t size, int *ret); 164 #else 165 static inline int dma_declare_coherent_memory(struct device *dev, 166 phys_addr_t phys_addr, dma_addr_t device_addr, size_t size) 167 { 168 return -ENOSYS; 169 } 170 171 #define dma_alloc_from_dev_coherent(dev, size, handle, ret) (0) 172 #define dma_release_from_dev_coherent(dev, order, vaddr) (0) 173 #define dma_mmap_from_dev_coherent(dev, vma, vaddr, order, ret) (0) 174 static inline void dma_release_coherent_memory(struct device *dev) { } 175 #endif /* CONFIG_DMA_DECLARE_COHERENT */ 176 177 #ifdef CONFIG_DMA_GLOBAL_POOL 178 void *dma_alloc_from_global_coherent(struct device *dev, ssize_t size, 179 dma_addr_t *dma_handle); 180 int dma_release_from_global_coherent(int order, void *vaddr); 181 int dma_mmap_from_global_coherent(struct vm_area_struct *vma, void *cpu_addr, 182 size_t size, int *ret); 183 int dma_init_global_coherent(phys_addr_t phys_addr, size_t size); 184 #else 185 static inline void *dma_alloc_from_global_coherent(struct device *dev, 186 ssize_t size, dma_addr_t *dma_handle) 187 { 188 return NULL; 189 } 190 static inline int dma_release_from_global_coherent(int order, void *vaddr) 191 { 192 return 0; 193 } 194 static inline int dma_mmap_from_global_coherent(struct vm_area_struct *vma, 195 void *cpu_addr, size_t size, int *ret) 196 { 197 return 0; 198 } 199 #endif /* CONFIG_DMA_GLOBAL_POOL */ 200 201 int dma_common_get_sgtable(struct device *dev, struct sg_table *sgt, 202 void *cpu_addr, dma_addr_t dma_addr, size_t size, 203 unsigned long attrs); 204 int dma_common_mmap(struct device *dev, struct vm_area_struct *vma, 205 void *cpu_addr, dma_addr_t dma_addr, size_t size, 206 unsigned long attrs); 207 struct page *dma_common_alloc_pages(struct device *dev, size_t size, 208 dma_addr_t *dma_handle, enum dma_data_direction dir, gfp_t gfp); 209 void dma_common_free_pages(struct device *dev, size_t size, struct page *vaddr, 210 dma_addr_t dma_handle, enum dma_data_direction dir); 211 212 struct page **dma_common_find_pages(void *cpu_addr); 213 void *dma_common_contiguous_remap(struct page *page, size_t size, pgprot_t prot, 214 const void *caller); 215 void *dma_common_pages_remap(struct page **pages, size_t size, pgprot_t prot, 216 const void *caller); 217 void dma_common_free_remap(void *cpu_addr, size_t size); 218 219 struct page *dma_alloc_from_pool(struct device *dev, size_t size, 220 void **cpu_addr, gfp_t flags, 221 bool (*phys_addr_ok)(struct device *, phys_addr_t, size_t)); 222 bool dma_free_from_pool(struct device *dev, void *start, size_t size); 223 224 int dma_direct_set_offset(struct device *dev, phys_addr_t cpu_start, 225 dma_addr_t dma_start, u64 size); 226 227 #if defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_DEVICE) || \ 228 defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU) || \ 229 defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU_ALL) 230 extern bool dma_default_coherent; 231 static inline bool dev_is_dma_coherent(struct device *dev) 232 { 233 return dev->dma_coherent; 234 } 235 #else 236 #define dma_default_coherent true 237 238 static inline bool dev_is_dma_coherent(struct device *dev) 239 { 240 return true; 241 } 242 #endif 243 244 static inline void dma_reset_need_sync(struct device *dev) 245 { 246 #ifdef CONFIG_DMA_NEED_SYNC 247 /* Reset it only once so that the function can be called on hotpath */ 248 if (unlikely(dev->dma_skip_sync)) 249 dev->dma_skip_sync = false; 250 #endif 251 } 252 253 /* 254 * Check whether potential kmalloc() buffers are safe for non-coherent DMA. 255 */ 256 static inline bool dma_kmalloc_safe(struct device *dev, 257 enum dma_data_direction dir) 258 { 259 /* 260 * If DMA bouncing of kmalloc() buffers is disabled, the kmalloc() 261 * caches have already been aligned to a DMA-safe size. 262 */ 263 if (!IS_ENABLED(CONFIG_DMA_BOUNCE_UNALIGNED_KMALLOC)) 264 return true; 265 266 /* 267 * kmalloc() buffers are DMA-safe irrespective of size if the device 268 * is coherent or the direction is DMA_TO_DEVICE (non-desctructive 269 * cache maintenance and benign cache line evictions). 270 */ 271 if (dev_is_dma_coherent(dev) || dir == DMA_TO_DEVICE) 272 return true; 273 274 return false; 275 } 276 277 /* 278 * Check whether the given size, assuming it is for a kmalloc()'ed buffer, is 279 * sufficiently aligned for non-coherent DMA. 280 */ 281 static inline bool dma_kmalloc_size_aligned(size_t size) 282 { 283 /* 284 * Larger kmalloc() sizes are guaranteed to be aligned to 285 * ARCH_DMA_MINALIGN. 286 */ 287 if (size >= 2 * ARCH_DMA_MINALIGN || 288 IS_ALIGNED(kmalloc_size_roundup(size), dma_get_cache_alignment())) 289 return true; 290 291 return false; 292 } 293 294 /* 295 * Check whether the given object size may have originated from a kmalloc() 296 * buffer with a slab alignment below the DMA-safe alignment and needs 297 * bouncing for non-coherent DMA. The pointer alignment is not considered and 298 * in-structure DMA-safe offsets are the responsibility of the caller. Such 299 * code should use the static ARCH_DMA_MINALIGN for compiler annotations. 300 * 301 * The heuristics can have false positives, bouncing unnecessarily, though the 302 * buffers would be small. False negatives are theoretically possible if, for 303 * example, multiple small kmalloc() buffers are coalesced into a larger 304 * buffer that passes the alignment check. There are no such known constructs 305 * in the kernel. 306 */ 307 static inline bool dma_kmalloc_needs_bounce(struct device *dev, size_t size, 308 enum dma_data_direction dir) 309 { 310 return !dma_kmalloc_safe(dev, dir) && !dma_kmalloc_size_aligned(size); 311 } 312 313 void *arch_dma_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle, 314 gfp_t gfp, unsigned long attrs); 315 void arch_dma_free(struct device *dev, size_t size, void *cpu_addr, 316 dma_addr_t dma_addr, unsigned long attrs); 317 318 #ifdef CONFIG_ARCH_HAS_DMA_SET_MASK 319 void arch_dma_set_mask(struct device *dev, u64 mask); 320 #else 321 #define arch_dma_set_mask(dev, mask) do { } while (0) 322 #endif 323 324 #ifdef CONFIG_MMU 325 /* 326 * Page protection so that devices that can't snoop CPU caches can use the 327 * memory coherently. We default to pgprot_noncached which is usually used 328 * for ioremap as a safe bet, but architectures can override this with less 329 * strict semantics if possible. 330 */ 331 #ifndef pgprot_dmacoherent 332 #define pgprot_dmacoherent(prot) pgprot_noncached(prot) 333 #endif 334 335 pgprot_t dma_pgprot(struct device *dev, pgprot_t prot, unsigned long attrs); 336 #else 337 static inline pgprot_t dma_pgprot(struct device *dev, pgprot_t prot, 338 unsigned long attrs) 339 { 340 return prot; /* no protection bits supported without page tables */ 341 } 342 #endif /* CONFIG_MMU */ 343 344 #ifdef CONFIG_ARCH_HAS_SYNC_DMA_FOR_DEVICE 345 void arch_sync_dma_for_device(phys_addr_t paddr, size_t size, 346 enum dma_data_direction dir); 347 #else 348 static inline void arch_sync_dma_for_device(phys_addr_t paddr, size_t size, 349 enum dma_data_direction dir) 350 { 351 } 352 #endif /* ARCH_HAS_SYNC_DMA_FOR_DEVICE */ 353 354 #ifdef CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU 355 void arch_sync_dma_for_cpu(phys_addr_t paddr, size_t size, 356 enum dma_data_direction dir); 357 #else 358 static inline void arch_sync_dma_for_cpu(phys_addr_t paddr, size_t size, 359 enum dma_data_direction dir) 360 { 361 } 362 #endif /* ARCH_HAS_SYNC_DMA_FOR_CPU */ 363 364 #ifdef CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU_ALL 365 void arch_sync_dma_for_cpu_all(void); 366 #else 367 static inline void arch_sync_dma_for_cpu_all(void) 368 { 369 } 370 #endif /* CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU_ALL */ 371 372 #ifdef CONFIG_ARCH_HAS_DMA_PREP_COHERENT 373 void arch_dma_prep_coherent(struct page *page, size_t size); 374 #else 375 static inline void arch_dma_prep_coherent(struct page *page, size_t size) 376 { 377 } 378 #endif /* CONFIG_ARCH_HAS_DMA_PREP_COHERENT */ 379 380 void *arch_dma_set_uncached(void *addr, size_t size); 381 void arch_dma_clear_uncached(void *addr, size_t size); 382 383 #ifdef CONFIG_ARCH_HAS_DMA_MAP_DIRECT 384 bool arch_dma_map_phys_direct(struct device *dev, phys_addr_t addr); 385 bool arch_dma_unmap_phys_direct(struct device *dev, dma_addr_t dma_handle); 386 bool arch_dma_map_sg_direct(struct device *dev, struct scatterlist *sg, 387 int nents); 388 bool arch_dma_unmap_sg_direct(struct device *dev, struct scatterlist *sg, 389 int nents); 390 bool arch_dma_alloc_direct(struct device *dev); 391 bool arch_dma_free_direct(struct device *dev, dma_addr_t dma_handle); 392 #else 393 #define arch_dma_map_phys_direct(d, a) (false) 394 #define arch_dma_unmap_phys_direct(d, a) (false) 395 #define arch_dma_map_sg_direct(d, s, n) (false) 396 #define arch_dma_unmap_sg_direct(d, s, n) (false) 397 #define arch_dma_alloc_direct(d) (false) 398 #define arch_dma_free_direct(d, a) (false) 399 #endif 400 401 #ifdef CONFIG_ARCH_HAS_SETUP_DMA_OPS 402 void arch_setup_dma_ops(struct device *dev, bool coherent); 403 #else 404 static inline void arch_setup_dma_ops(struct device *dev, bool coherent) 405 { 406 } 407 #endif /* CONFIG_ARCH_HAS_SETUP_DMA_OPS */ 408 409 #ifdef CONFIG_ARCH_HAS_TEARDOWN_DMA_OPS 410 void arch_teardown_dma_ops(struct device *dev); 411 #else 412 static inline void arch_teardown_dma_ops(struct device *dev) 413 { 414 } 415 #endif /* CONFIG_ARCH_HAS_TEARDOWN_DMA_OPS */ 416 417 #ifdef CONFIG_DMA_API_DEBUG 418 void dma_debug_add_bus(const struct bus_type *bus); 419 void debug_dma_dump_mappings(struct device *dev); 420 #else 421 static inline void dma_debug_add_bus(const struct bus_type *bus) 422 { 423 } 424 static inline void debug_dma_dump_mappings(struct device *dev) 425 { 426 } 427 #endif /* CONFIG_DMA_API_DEBUG */ 428 429 extern const struct dma_map_ops dma_dummy_ops; 430 #endif /* _LINUX_DMA_MAP_OPS_H */ 431