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 /* 17 * Values for struct dma_map_ops.flags: 18 * 19 * DMA_F_PCI_P2PDMA_SUPPORTED: Indicates the dma_map_ops implementation can 20 * handle PCI P2PDMA pages in the map_sg/unmap_sg operation. 21 */ 22 #define DMA_F_PCI_P2PDMA_SUPPORTED (1 << 0) 23 24 struct dma_map_ops { 25 unsigned int flags; 26 27 void *(*alloc)(struct device *dev, size_t size, 28 dma_addr_t *dma_handle, gfp_t gfp, 29 unsigned long attrs); 30 void (*free)(struct device *dev, size_t size, void *vaddr, 31 dma_addr_t dma_handle, unsigned long attrs); 32 struct page *(*alloc_pages)(struct device *dev, size_t size, 33 dma_addr_t *dma_handle, enum dma_data_direction dir, 34 gfp_t gfp); 35 void (*free_pages)(struct device *dev, size_t size, struct page *vaddr, 36 dma_addr_t dma_handle, enum dma_data_direction dir); 37 struct sg_table *(*alloc_noncontiguous)(struct device *dev, size_t size, 38 enum dma_data_direction dir, gfp_t gfp, 39 unsigned long attrs); 40 void (*free_noncontiguous)(struct device *dev, size_t size, 41 struct sg_table *sgt, enum dma_data_direction dir); 42 int (*mmap)(struct device *, struct vm_area_struct *, 43 void *, dma_addr_t, size_t, unsigned long attrs); 44 45 int (*get_sgtable)(struct device *dev, struct sg_table *sgt, 46 void *cpu_addr, dma_addr_t dma_addr, size_t size, 47 unsigned long attrs); 48 49 dma_addr_t (*map_page)(struct device *dev, struct page *page, 50 unsigned long offset, size_t size, 51 enum dma_data_direction dir, unsigned long attrs); 52 void (*unmap_page)(struct device *dev, dma_addr_t dma_handle, 53 size_t size, enum dma_data_direction dir, 54 unsigned long attrs); 55 /* 56 * map_sg should return a negative error code on error. See 57 * dma_map_sgtable() for a list of appropriate error codes 58 * and their meanings. 59 */ 60 int (*map_sg)(struct device *dev, struct scatterlist *sg, int nents, 61 enum dma_data_direction dir, unsigned long attrs); 62 void (*unmap_sg)(struct device *dev, struct scatterlist *sg, int nents, 63 enum dma_data_direction dir, unsigned long attrs); 64 dma_addr_t (*map_resource)(struct device *dev, phys_addr_t phys_addr, 65 size_t size, enum dma_data_direction dir, 66 unsigned long attrs); 67 void (*unmap_resource)(struct device *dev, dma_addr_t dma_handle, 68 size_t size, enum dma_data_direction dir, 69 unsigned long attrs); 70 void (*sync_single_for_cpu)(struct device *dev, dma_addr_t dma_handle, 71 size_t size, enum dma_data_direction dir); 72 void (*sync_single_for_device)(struct device *dev, 73 dma_addr_t dma_handle, size_t size, 74 enum dma_data_direction dir); 75 void (*sync_sg_for_cpu)(struct device *dev, struct scatterlist *sg, 76 int nents, enum dma_data_direction dir); 77 void (*sync_sg_for_device)(struct device *dev, struct scatterlist *sg, 78 int nents, enum dma_data_direction dir); 79 void (*cache_sync)(struct device *dev, void *vaddr, size_t size, 80 enum dma_data_direction direction); 81 int (*dma_supported)(struct device *dev, u64 mask); 82 u64 (*get_required_mask)(struct device *dev); 83 size_t (*max_mapping_size)(struct device *dev); 84 size_t (*opt_mapping_size)(void); 85 unsigned long (*get_merge_boundary)(struct device *dev); 86 }; 87 88 #ifdef CONFIG_DMA_OPS 89 #include <asm/dma-mapping.h> 90 91 static inline const struct dma_map_ops *get_dma_ops(struct device *dev) 92 { 93 if (dev->dma_ops) 94 return dev->dma_ops; 95 return get_arch_dma_ops(); 96 } 97 98 static inline void set_dma_ops(struct device *dev, 99 const struct dma_map_ops *dma_ops) 100 { 101 dev->dma_ops = dma_ops; 102 } 103 #else /* CONFIG_DMA_OPS */ 104 static inline const struct dma_map_ops *get_dma_ops(struct device *dev) 105 { 106 return NULL; 107 } 108 static inline void set_dma_ops(struct device *dev, 109 const struct dma_map_ops *dma_ops) 110 { 111 } 112 #endif /* CONFIG_DMA_OPS */ 113 114 #ifdef CONFIG_DMA_CMA 115 extern struct cma *dma_contiguous_default_area; 116 117 static inline struct cma *dev_get_cma_area(struct device *dev) 118 { 119 if (dev && dev->cma_area) 120 return dev->cma_area; 121 return dma_contiguous_default_area; 122 } 123 124 void dma_contiguous_reserve(phys_addr_t addr_limit); 125 int __init dma_contiguous_reserve_area(phys_addr_t size, phys_addr_t base, 126 phys_addr_t limit, struct cma **res_cma, bool fixed); 127 128 struct page *dma_alloc_from_contiguous(struct device *dev, size_t count, 129 unsigned int order, bool no_warn); 130 bool dma_release_from_contiguous(struct device *dev, struct page *pages, 131 int count); 132 struct page *dma_alloc_contiguous(struct device *dev, size_t size, gfp_t gfp); 133 void dma_free_contiguous(struct device *dev, struct page *page, size_t size); 134 135 void dma_contiguous_early_fixup(phys_addr_t base, unsigned long size); 136 #else /* CONFIG_DMA_CMA */ 137 static inline struct cma *dev_get_cma_area(struct device *dev) 138 { 139 return NULL; 140 } 141 static inline void dma_contiguous_reserve(phys_addr_t limit) 142 { 143 } 144 static inline int dma_contiguous_reserve_area(phys_addr_t size, 145 phys_addr_t base, phys_addr_t limit, struct cma **res_cma, 146 bool fixed) 147 { 148 return -ENOSYS; 149 } 150 static inline struct page *dma_alloc_from_contiguous(struct device *dev, 151 size_t count, unsigned int order, bool no_warn) 152 { 153 return NULL; 154 } 155 static inline bool dma_release_from_contiguous(struct device *dev, 156 struct page *pages, int count) 157 { 158 return false; 159 } 160 /* Use fallback alloc() and free() when CONFIG_DMA_CMA=n */ 161 static inline struct page *dma_alloc_contiguous(struct device *dev, size_t size, 162 gfp_t gfp) 163 { 164 return NULL; 165 } 166 static inline void dma_free_contiguous(struct device *dev, struct page *page, 167 size_t size) 168 { 169 __free_pages(page, get_order(size)); 170 } 171 #endif /* CONFIG_DMA_CMA*/ 172 173 #ifdef CONFIG_DMA_DECLARE_COHERENT 174 int dma_declare_coherent_memory(struct device *dev, phys_addr_t phys_addr, 175 dma_addr_t device_addr, size_t size); 176 void dma_release_coherent_memory(struct device *dev); 177 int dma_alloc_from_dev_coherent(struct device *dev, ssize_t size, 178 dma_addr_t *dma_handle, void **ret); 179 int dma_release_from_dev_coherent(struct device *dev, int order, void *vaddr); 180 int dma_mmap_from_dev_coherent(struct device *dev, struct vm_area_struct *vma, 181 void *cpu_addr, size_t size, int *ret); 182 #else 183 static inline int dma_declare_coherent_memory(struct device *dev, 184 phys_addr_t phys_addr, dma_addr_t device_addr, size_t size) 185 { 186 return -ENOSYS; 187 } 188 189 #define dma_alloc_from_dev_coherent(dev, size, handle, ret) (0) 190 #define dma_release_from_dev_coherent(dev, order, vaddr) (0) 191 #define dma_mmap_from_dev_coherent(dev, vma, vaddr, order, ret) (0) 192 static inline void dma_release_coherent_memory(struct device *dev) { } 193 #endif /* CONFIG_DMA_DECLARE_COHERENT */ 194 195 #ifdef CONFIG_DMA_GLOBAL_POOL 196 void *dma_alloc_from_global_coherent(struct device *dev, ssize_t size, 197 dma_addr_t *dma_handle); 198 int dma_release_from_global_coherent(int order, void *vaddr); 199 int dma_mmap_from_global_coherent(struct vm_area_struct *vma, void *cpu_addr, 200 size_t size, int *ret); 201 int dma_init_global_coherent(phys_addr_t phys_addr, size_t size); 202 #else 203 static inline void *dma_alloc_from_global_coherent(struct device *dev, 204 ssize_t size, dma_addr_t *dma_handle) 205 { 206 return NULL; 207 } 208 static inline int dma_release_from_global_coherent(int order, void *vaddr) 209 { 210 return 0; 211 } 212 static inline int dma_mmap_from_global_coherent(struct vm_area_struct *vma, 213 void *cpu_addr, size_t size, int *ret) 214 { 215 return 0; 216 } 217 #endif /* CONFIG_DMA_GLOBAL_POOL */ 218 219 /* 220 * This is the actual return value from the ->alloc_noncontiguous method. 221 * The users of the DMA API should only care about the sg_table, but to make 222 * the DMA-API internal vmaping and freeing easier we stash away the page 223 * array as well (except for the fallback case). This can go away any time, 224 * e.g. when a vmap-variant that takes a scatterlist comes along. 225 */ 226 struct dma_sgt_handle { 227 struct sg_table sgt; 228 struct page **pages; 229 }; 230 #define sgt_handle(sgt) \ 231 container_of((sgt), struct dma_sgt_handle, sgt) 232 233 int dma_common_get_sgtable(struct device *dev, struct sg_table *sgt, 234 void *cpu_addr, dma_addr_t dma_addr, size_t size, 235 unsigned long attrs); 236 int dma_common_mmap(struct device *dev, struct vm_area_struct *vma, 237 void *cpu_addr, dma_addr_t dma_addr, size_t size, 238 unsigned long attrs); 239 struct page *dma_common_alloc_pages(struct device *dev, size_t size, 240 dma_addr_t *dma_handle, enum dma_data_direction dir, gfp_t gfp); 241 void dma_common_free_pages(struct device *dev, size_t size, struct page *vaddr, 242 dma_addr_t dma_handle, enum dma_data_direction dir); 243 244 struct page **dma_common_find_pages(void *cpu_addr); 245 void *dma_common_contiguous_remap(struct page *page, size_t size, pgprot_t prot, 246 const void *caller); 247 void *dma_common_pages_remap(struct page **pages, size_t size, pgprot_t prot, 248 const void *caller); 249 void dma_common_free_remap(void *cpu_addr, size_t size); 250 251 struct page *dma_alloc_from_pool(struct device *dev, size_t size, 252 void **cpu_addr, gfp_t flags, 253 bool (*phys_addr_ok)(struct device *, phys_addr_t, size_t)); 254 bool dma_free_from_pool(struct device *dev, void *start, size_t size); 255 256 int dma_direct_set_offset(struct device *dev, phys_addr_t cpu_start, 257 dma_addr_t dma_start, u64 size); 258 259 #if defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_DEVICE) || \ 260 defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU) || \ 261 defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU_ALL) 262 extern bool dma_default_coherent; 263 static inline bool dev_is_dma_coherent(struct device *dev) 264 { 265 return dev->dma_coherent; 266 } 267 #else 268 #define dma_default_coherent true 269 270 static inline bool dev_is_dma_coherent(struct device *dev) 271 { 272 return true; 273 } 274 #endif /* CONFIG_ARCH_HAS_DMA_COHERENCE_H */ 275 276 /* 277 * Check whether potential kmalloc() buffers are safe for non-coherent DMA. 278 */ 279 static inline bool dma_kmalloc_safe(struct device *dev, 280 enum dma_data_direction dir) 281 { 282 /* 283 * If DMA bouncing of kmalloc() buffers is disabled, the kmalloc() 284 * caches have already been aligned to a DMA-safe size. 285 */ 286 if (!IS_ENABLED(CONFIG_DMA_BOUNCE_UNALIGNED_KMALLOC)) 287 return true; 288 289 /* 290 * kmalloc() buffers are DMA-safe irrespective of size if the device 291 * is coherent or the direction is DMA_TO_DEVICE (non-desctructive 292 * cache maintenance and benign cache line evictions). 293 */ 294 if (dev_is_dma_coherent(dev) || dir == DMA_TO_DEVICE) 295 return true; 296 297 return false; 298 } 299 300 /* 301 * Check whether the given size, assuming it is for a kmalloc()'ed buffer, is 302 * sufficiently aligned for non-coherent DMA. 303 */ 304 static inline bool dma_kmalloc_size_aligned(size_t size) 305 { 306 /* 307 * Larger kmalloc() sizes are guaranteed to be aligned to 308 * ARCH_DMA_MINALIGN. 309 */ 310 if (size >= 2 * ARCH_DMA_MINALIGN || 311 IS_ALIGNED(kmalloc_size_roundup(size), dma_get_cache_alignment())) 312 return true; 313 314 return false; 315 } 316 317 /* 318 * Check whether the given object size may have originated from a kmalloc() 319 * buffer with a slab alignment below the DMA-safe alignment and needs 320 * bouncing for non-coherent DMA. The pointer alignment is not considered and 321 * in-structure DMA-safe offsets are the responsibility of the caller. Such 322 * code should use the static ARCH_DMA_MINALIGN for compiler annotations. 323 * 324 * The heuristics can have false positives, bouncing unnecessarily, though the 325 * buffers would be small. False negatives are theoretically possible if, for 326 * example, multiple small kmalloc() buffers are coalesced into a larger 327 * buffer that passes the alignment check. There are no such known constructs 328 * in the kernel. 329 */ 330 static inline bool dma_kmalloc_needs_bounce(struct device *dev, size_t size, 331 enum dma_data_direction dir) 332 { 333 return !dma_kmalloc_safe(dev, dir) && !dma_kmalloc_size_aligned(size); 334 } 335 336 void *arch_dma_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle, 337 gfp_t gfp, unsigned long attrs); 338 void arch_dma_free(struct device *dev, size_t size, void *cpu_addr, 339 dma_addr_t dma_addr, unsigned long attrs); 340 341 #ifdef CONFIG_ARCH_HAS_DMA_SET_MASK 342 void arch_dma_set_mask(struct device *dev, u64 mask); 343 #else 344 #define arch_dma_set_mask(dev, mask) do { } while (0) 345 #endif 346 347 #ifdef CONFIG_MMU 348 /* 349 * Page protection so that devices that can't snoop CPU caches can use the 350 * memory coherently. We default to pgprot_noncached which is usually used 351 * for ioremap as a safe bet, but architectures can override this with less 352 * strict semantics if possible. 353 */ 354 #ifndef pgprot_dmacoherent 355 #define pgprot_dmacoherent(prot) pgprot_noncached(prot) 356 #endif 357 358 pgprot_t dma_pgprot(struct device *dev, pgprot_t prot, unsigned long attrs); 359 #else 360 static inline pgprot_t dma_pgprot(struct device *dev, pgprot_t prot, 361 unsigned long attrs) 362 { 363 return prot; /* no protection bits supported without page tables */ 364 } 365 #endif /* CONFIG_MMU */ 366 367 #ifdef CONFIG_ARCH_HAS_SYNC_DMA_FOR_DEVICE 368 void arch_sync_dma_for_device(phys_addr_t paddr, size_t size, 369 enum dma_data_direction dir); 370 #else 371 static inline void arch_sync_dma_for_device(phys_addr_t paddr, size_t size, 372 enum dma_data_direction dir) 373 { 374 } 375 #endif /* ARCH_HAS_SYNC_DMA_FOR_DEVICE */ 376 377 #ifdef CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU 378 void arch_sync_dma_for_cpu(phys_addr_t paddr, size_t size, 379 enum dma_data_direction dir); 380 #else 381 static inline void arch_sync_dma_for_cpu(phys_addr_t paddr, size_t size, 382 enum dma_data_direction dir) 383 { 384 } 385 #endif /* ARCH_HAS_SYNC_DMA_FOR_CPU */ 386 387 #ifdef CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU_ALL 388 void arch_sync_dma_for_cpu_all(void); 389 #else 390 static inline void arch_sync_dma_for_cpu_all(void) 391 { 392 } 393 #endif /* CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU_ALL */ 394 395 #ifdef CONFIG_ARCH_HAS_DMA_PREP_COHERENT 396 void arch_dma_prep_coherent(struct page *page, size_t size); 397 #else 398 static inline void arch_dma_prep_coherent(struct page *page, size_t size) 399 { 400 } 401 #endif /* CONFIG_ARCH_HAS_DMA_PREP_COHERENT */ 402 403 #ifdef CONFIG_ARCH_HAS_DMA_MARK_CLEAN 404 void arch_dma_mark_clean(phys_addr_t paddr, size_t size); 405 #else 406 static inline void arch_dma_mark_clean(phys_addr_t paddr, size_t size) 407 { 408 } 409 #endif /* ARCH_HAS_DMA_MARK_CLEAN */ 410 411 void *arch_dma_set_uncached(void *addr, size_t size); 412 void arch_dma_clear_uncached(void *addr, size_t size); 413 414 #ifdef CONFIG_ARCH_HAS_DMA_MAP_DIRECT 415 bool arch_dma_map_page_direct(struct device *dev, phys_addr_t addr); 416 bool arch_dma_unmap_page_direct(struct device *dev, dma_addr_t dma_handle); 417 bool arch_dma_map_sg_direct(struct device *dev, struct scatterlist *sg, 418 int nents); 419 bool arch_dma_unmap_sg_direct(struct device *dev, struct scatterlist *sg, 420 int nents); 421 #else 422 #define arch_dma_map_page_direct(d, a) (false) 423 #define arch_dma_unmap_page_direct(d, a) (false) 424 #define arch_dma_map_sg_direct(d, s, n) (false) 425 #define arch_dma_unmap_sg_direct(d, s, n) (false) 426 #endif 427 428 #ifdef CONFIG_ARCH_HAS_SETUP_DMA_OPS 429 void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size, 430 bool coherent); 431 #else 432 static inline void arch_setup_dma_ops(struct device *dev, u64 dma_base, 433 u64 size, bool coherent) 434 { 435 } 436 #endif /* CONFIG_ARCH_HAS_SETUP_DMA_OPS */ 437 438 #ifdef CONFIG_ARCH_HAS_TEARDOWN_DMA_OPS 439 void arch_teardown_dma_ops(struct device *dev); 440 #else 441 static inline void arch_teardown_dma_ops(struct device *dev) 442 { 443 } 444 #endif /* CONFIG_ARCH_HAS_TEARDOWN_DMA_OPS */ 445 446 #ifdef CONFIG_DMA_API_DEBUG 447 void dma_debug_add_bus(const struct bus_type *bus); 448 void debug_dma_dump_mappings(struct device *dev); 449 #else 450 static inline void dma_debug_add_bus(const struct bus_type *bus) 451 { 452 } 453 static inline void debug_dma_dump_mappings(struct device *dev) 454 { 455 } 456 #endif /* CONFIG_DMA_API_DEBUG */ 457 458 extern const struct dma_map_ops dma_dummy_ops; 459 460 enum pci_p2pdma_map_type { 461 /* 462 * PCI_P2PDMA_MAP_UNKNOWN: Used internally for indicating the mapping 463 * type hasn't been calculated yet. Functions that return this enum 464 * never return this value. 465 */ 466 PCI_P2PDMA_MAP_UNKNOWN = 0, 467 468 /* 469 * PCI_P2PDMA_MAP_NOT_SUPPORTED: Indicates the transaction will 470 * traverse the host bridge and the host bridge is not in the 471 * allowlist. DMA Mapping routines should return an error when 472 * this is returned. 473 */ 474 PCI_P2PDMA_MAP_NOT_SUPPORTED, 475 476 /* 477 * PCI_P2PDMA_BUS_ADDR: Indicates that two devices can talk to 478 * each other directly through a PCI switch and the transaction will 479 * not traverse the host bridge. Such a mapping should program 480 * the DMA engine with PCI bus addresses. 481 */ 482 PCI_P2PDMA_MAP_BUS_ADDR, 483 484 /* 485 * PCI_P2PDMA_MAP_THRU_HOST_BRIDGE: Indicates two devices can talk 486 * to each other, but the transaction traverses a host bridge on the 487 * allowlist. In this case, a normal mapping either with CPU physical 488 * addresses (in the case of dma-direct) or IOVA addresses (in the 489 * case of IOMMUs) should be used to program the DMA engine. 490 */ 491 PCI_P2PDMA_MAP_THRU_HOST_BRIDGE, 492 }; 493 494 struct pci_p2pdma_map_state { 495 struct dev_pagemap *pgmap; 496 int map; 497 u64 bus_off; 498 }; 499 500 #ifdef CONFIG_PCI_P2PDMA 501 enum pci_p2pdma_map_type 502 pci_p2pdma_map_segment(struct pci_p2pdma_map_state *state, struct device *dev, 503 struct scatterlist *sg); 504 #else /* CONFIG_PCI_P2PDMA */ 505 static inline enum pci_p2pdma_map_type 506 pci_p2pdma_map_segment(struct pci_p2pdma_map_state *state, struct device *dev, 507 struct scatterlist *sg) 508 { 509 return PCI_P2PDMA_MAP_NOT_SUPPORTED; 510 } 511 #endif /* CONFIG_PCI_P2PDMA */ 512 513 #endif /* _LINUX_DMA_MAP_OPS_H */ 514