1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * arch-independent dma-mapping routines 4 * 5 * Copyright (c) 2006 SUSE Linux Products GmbH 6 * Copyright (c) 2006 Tejun Heo <teheo@suse.de> 7 */ 8 #include <linux/memblock.h> /* for max_pfn */ 9 #include <linux/acpi.h> 10 #include <linux/dma-map-ops.h> 11 #include <linux/export.h> 12 #include <linux/gfp.h> 13 #include <linux/kmsan.h> 14 #include <linux/of_device.h> 15 #include <linux/slab.h> 16 #include <linux/vmalloc.h> 17 #include "debug.h" 18 #include "direct.h" 19 20 bool dma_default_coherent; 21 22 /* 23 * Managed DMA API 24 */ 25 struct dma_devres { 26 size_t size; 27 void *vaddr; 28 dma_addr_t dma_handle; 29 unsigned long attrs; 30 }; 31 32 static void dmam_release(struct device *dev, void *res) 33 { 34 struct dma_devres *this = res; 35 36 dma_free_attrs(dev, this->size, this->vaddr, this->dma_handle, 37 this->attrs); 38 } 39 40 static int dmam_match(struct device *dev, void *res, void *match_data) 41 { 42 struct dma_devres *this = res, *match = match_data; 43 44 if (this->vaddr == match->vaddr) { 45 WARN_ON(this->size != match->size || 46 this->dma_handle != match->dma_handle); 47 return 1; 48 } 49 return 0; 50 } 51 52 /** 53 * dmam_free_coherent - Managed dma_free_coherent() 54 * @dev: Device to free coherent memory for 55 * @size: Size of allocation 56 * @vaddr: Virtual address of the memory to free 57 * @dma_handle: DMA handle of the memory to free 58 * 59 * Managed dma_free_coherent(). 60 */ 61 void dmam_free_coherent(struct device *dev, size_t size, void *vaddr, 62 dma_addr_t dma_handle) 63 { 64 struct dma_devres match_data = { size, vaddr, dma_handle }; 65 66 dma_free_coherent(dev, size, vaddr, dma_handle); 67 WARN_ON(devres_destroy(dev, dmam_release, dmam_match, &match_data)); 68 } 69 EXPORT_SYMBOL(dmam_free_coherent); 70 71 /** 72 * dmam_alloc_attrs - Managed dma_alloc_attrs() 73 * @dev: Device to allocate non_coherent memory for 74 * @size: Size of allocation 75 * @dma_handle: Out argument for allocated DMA handle 76 * @gfp: Allocation flags 77 * @attrs: Flags in the DMA_ATTR_* namespace. 78 * 79 * Managed dma_alloc_attrs(). Memory allocated using this function will be 80 * automatically released on driver detach. 81 * 82 * RETURNS: 83 * Pointer to allocated memory on success, NULL on failure. 84 */ 85 void *dmam_alloc_attrs(struct device *dev, size_t size, dma_addr_t *dma_handle, 86 gfp_t gfp, unsigned long attrs) 87 { 88 struct dma_devres *dr; 89 void *vaddr; 90 91 dr = devres_alloc(dmam_release, sizeof(*dr), gfp); 92 if (!dr) 93 return NULL; 94 95 vaddr = dma_alloc_attrs(dev, size, dma_handle, gfp, attrs); 96 if (!vaddr) { 97 devres_free(dr); 98 return NULL; 99 } 100 101 dr->vaddr = vaddr; 102 dr->dma_handle = *dma_handle; 103 dr->size = size; 104 dr->attrs = attrs; 105 106 devres_add(dev, dr); 107 108 return vaddr; 109 } 110 EXPORT_SYMBOL(dmam_alloc_attrs); 111 112 static bool dma_go_direct(struct device *dev, dma_addr_t mask, 113 const struct dma_map_ops *ops) 114 { 115 if (likely(!ops)) 116 return true; 117 #ifdef CONFIG_DMA_OPS_BYPASS 118 if (dev->dma_ops_bypass) 119 return min_not_zero(mask, dev->bus_dma_limit) >= 120 dma_direct_get_required_mask(dev); 121 #endif 122 return false; 123 } 124 125 126 /* 127 * Check if the devices uses a direct mapping for streaming DMA operations. 128 * This allows IOMMU drivers to set a bypass mode if the DMA mask is large 129 * enough. 130 */ 131 static inline bool dma_alloc_direct(struct device *dev, 132 const struct dma_map_ops *ops) 133 { 134 return dma_go_direct(dev, dev->coherent_dma_mask, ops); 135 } 136 137 static inline bool dma_map_direct(struct device *dev, 138 const struct dma_map_ops *ops) 139 { 140 return dma_go_direct(dev, *dev->dma_mask, ops); 141 } 142 143 dma_addr_t dma_map_page_attrs(struct device *dev, struct page *page, 144 size_t offset, size_t size, enum dma_data_direction dir, 145 unsigned long attrs) 146 { 147 const struct dma_map_ops *ops = get_dma_ops(dev); 148 dma_addr_t addr; 149 150 BUG_ON(!valid_dma_direction(dir)); 151 152 if (WARN_ON_ONCE(!dev->dma_mask)) 153 return DMA_MAPPING_ERROR; 154 155 if (dma_map_direct(dev, ops) || 156 arch_dma_map_page_direct(dev, page_to_phys(page) + offset + size)) 157 addr = dma_direct_map_page(dev, page, offset, size, dir, attrs); 158 else 159 addr = ops->map_page(dev, page, offset, size, dir, attrs); 160 kmsan_handle_dma(page, offset, size, dir); 161 debug_dma_map_page(dev, page, offset, size, dir, addr, attrs); 162 163 return addr; 164 } 165 EXPORT_SYMBOL(dma_map_page_attrs); 166 167 void dma_unmap_page_attrs(struct device *dev, dma_addr_t addr, size_t size, 168 enum dma_data_direction dir, unsigned long attrs) 169 { 170 const struct dma_map_ops *ops = get_dma_ops(dev); 171 172 BUG_ON(!valid_dma_direction(dir)); 173 if (dma_map_direct(dev, ops) || 174 arch_dma_unmap_page_direct(dev, addr + size)) 175 dma_direct_unmap_page(dev, addr, size, dir, attrs); 176 else if (ops->unmap_page) 177 ops->unmap_page(dev, addr, size, dir, attrs); 178 debug_dma_unmap_page(dev, addr, size, dir); 179 } 180 EXPORT_SYMBOL(dma_unmap_page_attrs); 181 182 static int __dma_map_sg_attrs(struct device *dev, struct scatterlist *sg, 183 int nents, enum dma_data_direction dir, unsigned long attrs) 184 { 185 const struct dma_map_ops *ops = get_dma_ops(dev); 186 int ents; 187 188 BUG_ON(!valid_dma_direction(dir)); 189 190 if (WARN_ON_ONCE(!dev->dma_mask)) 191 return 0; 192 193 if (dma_map_direct(dev, ops) || 194 arch_dma_map_sg_direct(dev, sg, nents)) 195 ents = dma_direct_map_sg(dev, sg, nents, dir, attrs); 196 else 197 ents = ops->map_sg(dev, sg, nents, dir, attrs); 198 199 if (ents > 0) { 200 kmsan_handle_dma_sg(sg, nents, dir); 201 debug_dma_map_sg(dev, sg, nents, ents, dir, attrs); 202 } else if (WARN_ON_ONCE(ents != -EINVAL && ents != -ENOMEM && 203 ents != -EIO && ents != -EREMOTEIO)) { 204 return -EIO; 205 } 206 207 return ents; 208 } 209 210 /** 211 * dma_map_sg_attrs - Map the given buffer for DMA 212 * @dev: The device for which to perform the DMA operation 213 * @sg: The sg_table object describing the buffer 214 * @nents: Number of entries to map 215 * @dir: DMA direction 216 * @attrs: Optional DMA attributes for the map operation 217 * 218 * Maps a buffer described by a scatterlist passed in the sg argument with 219 * nents segments for the @dir DMA operation by the @dev device. 220 * 221 * Returns the number of mapped entries (which can be less than nents) 222 * on success. Zero is returned for any error. 223 * 224 * dma_unmap_sg_attrs() should be used to unmap the buffer with the 225 * original sg and original nents (not the value returned by this funciton). 226 */ 227 unsigned int dma_map_sg_attrs(struct device *dev, struct scatterlist *sg, 228 int nents, enum dma_data_direction dir, unsigned long attrs) 229 { 230 int ret; 231 232 ret = __dma_map_sg_attrs(dev, sg, nents, dir, attrs); 233 if (ret < 0) 234 return 0; 235 return ret; 236 } 237 EXPORT_SYMBOL(dma_map_sg_attrs); 238 239 /** 240 * dma_map_sgtable - Map the given buffer for DMA 241 * @dev: The device for which to perform the DMA operation 242 * @sgt: The sg_table object describing the buffer 243 * @dir: DMA direction 244 * @attrs: Optional DMA attributes for the map operation 245 * 246 * Maps a buffer described by a scatterlist stored in the given sg_table 247 * object for the @dir DMA operation by the @dev device. After success, the 248 * ownership for the buffer is transferred to the DMA domain. One has to 249 * call dma_sync_sgtable_for_cpu() or dma_unmap_sgtable() to move the 250 * ownership of the buffer back to the CPU domain before touching the 251 * buffer by the CPU. 252 * 253 * Returns 0 on success or a negative error code on error. The following 254 * error codes are supported with the given meaning: 255 * 256 * -EINVAL An invalid argument, unaligned access or other error 257 * in usage. Will not succeed if retried. 258 * -ENOMEM Insufficient resources (like memory or IOVA space) to 259 * complete the mapping. Should succeed if retried later. 260 * -EIO Legacy error code with an unknown meaning. eg. this is 261 * returned if a lower level call returned 262 * DMA_MAPPING_ERROR. 263 * -EREMOTEIO The DMA device cannot access P2PDMA memory specified 264 * in the sg_table. This will not succeed if retried. 265 */ 266 int dma_map_sgtable(struct device *dev, struct sg_table *sgt, 267 enum dma_data_direction dir, unsigned long attrs) 268 { 269 int nents; 270 271 nents = __dma_map_sg_attrs(dev, sgt->sgl, sgt->orig_nents, dir, attrs); 272 if (nents < 0) 273 return nents; 274 sgt->nents = nents; 275 return 0; 276 } 277 EXPORT_SYMBOL_GPL(dma_map_sgtable); 278 279 void dma_unmap_sg_attrs(struct device *dev, struct scatterlist *sg, 280 int nents, enum dma_data_direction dir, 281 unsigned long attrs) 282 { 283 const struct dma_map_ops *ops = get_dma_ops(dev); 284 285 BUG_ON(!valid_dma_direction(dir)); 286 debug_dma_unmap_sg(dev, sg, nents, dir); 287 if (dma_map_direct(dev, ops) || 288 arch_dma_unmap_sg_direct(dev, sg, nents)) 289 dma_direct_unmap_sg(dev, sg, nents, dir, attrs); 290 else if (ops->unmap_sg) 291 ops->unmap_sg(dev, sg, nents, dir, attrs); 292 } 293 EXPORT_SYMBOL(dma_unmap_sg_attrs); 294 295 dma_addr_t dma_map_resource(struct device *dev, phys_addr_t phys_addr, 296 size_t size, enum dma_data_direction dir, unsigned long attrs) 297 { 298 const struct dma_map_ops *ops = get_dma_ops(dev); 299 dma_addr_t addr = DMA_MAPPING_ERROR; 300 301 BUG_ON(!valid_dma_direction(dir)); 302 303 if (WARN_ON_ONCE(!dev->dma_mask)) 304 return DMA_MAPPING_ERROR; 305 306 if (dma_map_direct(dev, ops)) 307 addr = dma_direct_map_resource(dev, phys_addr, size, dir, attrs); 308 else if (ops->map_resource) 309 addr = ops->map_resource(dev, phys_addr, size, dir, attrs); 310 311 debug_dma_map_resource(dev, phys_addr, size, dir, addr, attrs); 312 return addr; 313 } 314 EXPORT_SYMBOL(dma_map_resource); 315 316 void dma_unmap_resource(struct device *dev, dma_addr_t addr, size_t size, 317 enum dma_data_direction dir, unsigned long attrs) 318 { 319 const struct dma_map_ops *ops = get_dma_ops(dev); 320 321 BUG_ON(!valid_dma_direction(dir)); 322 if (!dma_map_direct(dev, ops) && ops->unmap_resource) 323 ops->unmap_resource(dev, addr, size, dir, attrs); 324 debug_dma_unmap_resource(dev, addr, size, dir); 325 } 326 EXPORT_SYMBOL(dma_unmap_resource); 327 328 void dma_sync_single_for_cpu(struct device *dev, dma_addr_t addr, size_t size, 329 enum dma_data_direction dir) 330 { 331 const struct dma_map_ops *ops = get_dma_ops(dev); 332 333 BUG_ON(!valid_dma_direction(dir)); 334 if (dma_map_direct(dev, ops)) 335 dma_direct_sync_single_for_cpu(dev, addr, size, dir); 336 else if (ops->sync_single_for_cpu) 337 ops->sync_single_for_cpu(dev, addr, size, dir); 338 debug_dma_sync_single_for_cpu(dev, addr, size, dir); 339 } 340 EXPORT_SYMBOL(dma_sync_single_for_cpu); 341 342 void dma_sync_single_for_device(struct device *dev, dma_addr_t addr, 343 size_t size, enum dma_data_direction dir) 344 { 345 const struct dma_map_ops *ops = get_dma_ops(dev); 346 347 BUG_ON(!valid_dma_direction(dir)); 348 if (dma_map_direct(dev, ops)) 349 dma_direct_sync_single_for_device(dev, addr, size, dir); 350 else if (ops->sync_single_for_device) 351 ops->sync_single_for_device(dev, addr, size, dir); 352 debug_dma_sync_single_for_device(dev, addr, size, dir); 353 } 354 EXPORT_SYMBOL(dma_sync_single_for_device); 355 356 void dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg, 357 int nelems, enum dma_data_direction dir) 358 { 359 const struct dma_map_ops *ops = get_dma_ops(dev); 360 361 BUG_ON(!valid_dma_direction(dir)); 362 if (dma_map_direct(dev, ops)) 363 dma_direct_sync_sg_for_cpu(dev, sg, nelems, dir); 364 else if (ops->sync_sg_for_cpu) 365 ops->sync_sg_for_cpu(dev, sg, nelems, dir); 366 debug_dma_sync_sg_for_cpu(dev, sg, nelems, dir); 367 } 368 EXPORT_SYMBOL(dma_sync_sg_for_cpu); 369 370 void dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg, 371 int nelems, enum dma_data_direction dir) 372 { 373 const struct dma_map_ops *ops = get_dma_ops(dev); 374 375 BUG_ON(!valid_dma_direction(dir)); 376 if (dma_map_direct(dev, ops)) 377 dma_direct_sync_sg_for_device(dev, sg, nelems, dir); 378 else if (ops->sync_sg_for_device) 379 ops->sync_sg_for_device(dev, sg, nelems, dir); 380 debug_dma_sync_sg_for_device(dev, sg, nelems, dir); 381 } 382 EXPORT_SYMBOL(dma_sync_sg_for_device); 383 384 /* 385 * The whole dma_get_sgtable() idea is fundamentally unsafe - it seems 386 * that the intention is to allow exporting memory allocated via the 387 * coherent DMA APIs through the dma_buf API, which only accepts a 388 * scattertable. This presents a couple of problems: 389 * 1. Not all memory allocated via the coherent DMA APIs is backed by 390 * a struct page 391 * 2. Passing coherent DMA memory into the streaming APIs is not allowed 392 * as we will try to flush the memory through a different alias to that 393 * actually being used (and the flushes are redundant.) 394 */ 395 int dma_get_sgtable_attrs(struct device *dev, struct sg_table *sgt, 396 void *cpu_addr, dma_addr_t dma_addr, size_t size, 397 unsigned long attrs) 398 { 399 const struct dma_map_ops *ops = get_dma_ops(dev); 400 401 if (dma_alloc_direct(dev, ops)) 402 return dma_direct_get_sgtable(dev, sgt, cpu_addr, dma_addr, 403 size, attrs); 404 if (!ops->get_sgtable) 405 return -ENXIO; 406 return ops->get_sgtable(dev, sgt, cpu_addr, dma_addr, size, attrs); 407 } 408 EXPORT_SYMBOL(dma_get_sgtable_attrs); 409 410 #ifdef CONFIG_MMU 411 /* 412 * Return the page attributes used for mapping dma_alloc_* memory, either in 413 * kernel space if remapping is needed, or to userspace through dma_mmap_*. 414 */ 415 pgprot_t dma_pgprot(struct device *dev, pgprot_t prot, unsigned long attrs) 416 { 417 if (dev_is_dma_coherent(dev)) 418 return prot; 419 #ifdef CONFIG_ARCH_HAS_DMA_WRITE_COMBINE 420 if (attrs & DMA_ATTR_WRITE_COMBINE) 421 return pgprot_writecombine(prot); 422 #endif 423 return pgprot_dmacoherent(prot); 424 } 425 #endif /* CONFIG_MMU */ 426 427 /** 428 * dma_can_mmap - check if a given device supports dma_mmap_* 429 * @dev: device to check 430 * 431 * Returns %true if @dev supports dma_mmap_coherent() and dma_mmap_attrs() to 432 * map DMA allocations to userspace. 433 */ 434 bool dma_can_mmap(struct device *dev) 435 { 436 const struct dma_map_ops *ops = get_dma_ops(dev); 437 438 if (dma_alloc_direct(dev, ops)) 439 return dma_direct_can_mmap(dev); 440 return ops->mmap != NULL; 441 } 442 EXPORT_SYMBOL_GPL(dma_can_mmap); 443 444 /** 445 * dma_mmap_attrs - map a coherent DMA allocation into user space 446 * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices 447 * @vma: vm_area_struct describing requested user mapping 448 * @cpu_addr: kernel CPU-view address returned from dma_alloc_attrs 449 * @dma_addr: device-view address returned from dma_alloc_attrs 450 * @size: size of memory originally requested in dma_alloc_attrs 451 * @attrs: attributes of mapping properties requested in dma_alloc_attrs 452 * 453 * Map a coherent DMA buffer previously allocated by dma_alloc_attrs into user 454 * space. The coherent DMA buffer must not be freed by the driver until the 455 * user space mapping has been released. 456 */ 457 int dma_mmap_attrs(struct device *dev, struct vm_area_struct *vma, 458 void *cpu_addr, dma_addr_t dma_addr, size_t size, 459 unsigned long attrs) 460 { 461 const struct dma_map_ops *ops = get_dma_ops(dev); 462 463 if (dma_alloc_direct(dev, ops)) 464 return dma_direct_mmap(dev, vma, cpu_addr, dma_addr, size, 465 attrs); 466 if (!ops->mmap) 467 return -ENXIO; 468 return ops->mmap(dev, vma, cpu_addr, dma_addr, size, attrs); 469 } 470 EXPORT_SYMBOL(dma_mmap_attrs); 471 472 u64 dma_get_required_mask(struct device *dev) 473 { 474 const struct dma_map_ops *ops = get_dma_ops(dev); 475 476 if (dma_alloc_direct(dev, ops)) 477 return dma_direct_get_required_mask(dev); 478 if (ops->get_required_mask) 479 return ops->get_required_mask(dev); 480 481 /* 482 * We require every DMA ops implementation to at least support a 32-bit 483 * DMA mask (and use bounce buffering if that isn't supported in 484 * hardware). As the direct mapping code has its own routine to 485 * actually report an optimal mask we default to 32-bit here as that 486 * is the right thing for most IOMMUs, and at least not actively 487 * harmful in general. 488 */ 489 return DMA_BIT_MASK(32); 490 } 491 EXPORT_SYMBOL_GPL(dma_get_required_mask); 492 493 void *dma_alloc_attrs(struct device *dev, size_t size, dma_addr_t *dma_handle, 494 gfp_t flag, unsigned long attrs) 495 { 496 const struct dma_map_ops *ops = get_dma_ops(dev); 497 void *cpu_addr; 498 499 WARN_ON_ONCE(!dev->coherent_dma_mask); 500 501 if (dma_alloc_from_dev_coherent(dev, size, dma_handle, &cpu_addr)) 502 return cpu_addr; 503 504 /* let the implementation decide on the zone to allocate from: */ 505 flag &= ~(__GFP_DMA | __GFP_DMA32 | __GFP_HIGHMEM); 506 507 if (dma_alloc_direct(dev, ops)) 508 cpu_addr = dma_direct_alloc(dev, size, dma_handle, flag, attrs); 509 else if (ops->alloc) 510 cpu_addr = ops->alloc(dev, size, dma_handle, flag, attrs); 511 else 512 return NULL; 513 514 debug_dma_alloc_coherent(dev, size, *dma_handle, cpu_addr, attrs); 515 return cpu_addr; 516 } 517 EXPORT_SYMBOL(dma_alloc_attrs); 518 519 void dma_free_attrs(struct device *dev, size_t size, void *cpu_addr, 520 dma_addr_t dma_handle, unsigned long attrs) 521 { 522 const struct dma_map_ops *ops = get_dma_ops(dev); 523 524 if (dma_release_from_dev_coherent(dev, get_order(size), cpu_addr)) 525 return; 526 /* 527 * On non-coherent platforms which implement DMA-coherent buffers via 528 * non-cacheable remaps, ops->free() may call vunmap(). Thus getting 529 * this far in IRQ context is a) at risk of a BUG_ON() or trying to 530 * sleep on some machines, and b) an indication that the driver is 531 * probably misusing the coherent API anyway. 532 */ 533 WARN_ON(irqs_disabled()); 534 535 if (!cpu_addr) 536 return; 537 538 debug_dma_free_coherent(dev, size, cpu_addr, dma_handle); 539 if (dma_alloc_direct(dev, ops)) 540 dma_direct_free(dev, size, cpu_addr, dma_handle, attrs); 541 else if (ops->free) 542 ops->free(dev, size, cpu_addr, dma_handle, attrs); 543 } 544 EXPORT_SYMBOL(dma_free_attrs); 545 546 static struct page *__dma_alloc_pages(struct device *dev, size_t size, 547 dma_addr_t *dma_handle, enum dma_data_direction dir, gfp_t gfp) 548 { 549 const struct dma_map_ops *ops = get_dma_ops(dev); 550 551 if (WARN_ON_ONCE(!dev->coherent_dma_mask)) 552 return NULL; 553 if (WARN_ON_ONCE(gfp & (__GFP_DMA | __GFP_DMA32 | __GFP_HIGHMEM))) 554 return NULL; 555 556 size = PAGE_ALIGN(size); 557 if (dma_alloc_direct(dev, ops)) 558 return dma_direct_alloc_pages(dev, size, dma_handle, dir, gfp); 559 if (!ops->alloc_pages) 560 return NULL; 561 return ops->alloc_pages(dev, size, dma_handle, dir, gfp); 562 } 563 564 struct page *dma_alloc_pages(struct device *dev, size_t size, 565 dma_addr_t *dma_handle, enum dma_data_direction dir, gfp_t gfp) 566 { 567 struct page *page = __dma_alloc_pages(dev, size, dma_handle, dir, gfp); 568 569 if (page) 570 debug_dma_map_page(dev, page, 0, size, dir, *dma_handle, 0); 571 return page; 572 } 573 EXPORT_SYMBOL_GPL(dma_alloc_pages); 574 575 static void __dma_free_pages(struct device *dev, size_t size, struct page *page, 576 dma_addr_t dma_handle, enum dma_data_direction dir) 577 { 578 const struct dma_map_ops *ops = get_dma_ops(dev); 579 580 size = PAGE_ALIGN(size); 581 if (dma_alloc_direct(dev, ops)) 582 dma_direct_free_pages(dev, size, page, dma_handle, dir); 583 else if (ops->free_pages) 584 ops->free_pages(dev, size, page, dma_handle, dir); 585 } 586 587 void dma_free_pages(struct device *dev, size_t size, struct page *page, 588 dma_addr_t dma_handle, enum dma_data_direction dir) 589 { 590 debug_dma_unmap_page(dev, dma_handle, size, dir); 591 __dma_free_pages(dev, size, page, dma_handle, dir); 592 } 593 EXPORT_SYMBOL_GPL(dma_free_pages); 594 595 int dma_mmap_pages(struct device *dev, struct vm_area_struct *vma, 596 size_t size, struct page *page) 597 { 598 unsigned long count = PAGE_ALIGN(size) >> PAGE_SHIFT; 599 600 if (vma->vm_pgoff >= count || vma_pages(vma) > count - vma->vm_pgoff) 601 return -ENXIO; 602 return remap_pfn_range(vma, vma->vm_start, 603 page_to_pfn(page) + vma->vm_pgoff, 604 vma_pages(vma) << PAGE_SHIFT, vma->vm_page_prot); 605 } 606 EXPORT_SYMBOL_GPL(dma_mmap_pages); 607 608 static struct sg_table *alloc_single_sgt(struct device *dev, size_t size, 609 enum dma_data_direction dir, gfp_t gfp) 610 { 611 struct sg_table *sgt; 612 struct page *page; 613 614 sgt = kmalloc(sizeof(*sgt), gfp); 615 if (!sgt) 616 return NULL; 617 if (sg_alloc_table(sgt, 1, gfp)) 618 goto out_free_sgt; 619 page = __dma_alloc_pages(dev, size, &sgt->sgl->dma_address, dir, gfp); 620 if (!page) 621 goto out_free_table; 622 sg_set_page(sgt->sgl, page, PAGE_ALIGN(size), 0); 623 sg_dma_len(sgt->sgl) = sgt->sgl->length; 624 return sgt; 625 out_free_table: 626 sg_free_table(sgt); 627 out_free_sgt: 628 kfree(sgt); 629 return NULL; 630 } 631 632 struct sg_table *dma_alloc_noncontiguous(struct device *dev, size_t size, 633 enum dma_data_direction dir, gfp_t gfp, unsigned long attrs) 634 { 635 const struct dma_map_ops *ops = get_dma_ops(dev); 636 struct sg_table *sgt; 637 638 if (WARN_ON_ONCE(attrs & ~DMA_ATTR_ALLOC_SINGLE_PAGES)) 639 return NULL; 640 641 if (ops && ops->alloc_noncontiguous) 642 sgt = ops->alloc_noncontiguous(dev, size, dir, gfp, attrs); 643 else 644 sgt = alloc_single_sgt(dev, size, dir, gfp); 645 646 if (sgt) { 647 sgt->nents = 1; 648 debug_dma_map_sg(dev, sgt->sgl, sgt->orig_nents, 1, dir, attrs); 649 } 650 return sgt; 651 } 652 EXPORT_SYMBOL_GPL(dma_alloc_noncontiguous); 653 654 static void free_single_sgt(struct device *dev, size_t size, 655 struct sg_table *sgt, enum dma_data_direction dir) 656 { 657 __dma_free_pages(dev, size, sg_page(sgt->sgl), sgt->sgl->dma_address, 658 dir); 659 sg_free_table(sgt); 660 kfree(sgt); 661 } 662 663 void dma_free_noncontiguous(struct device *dev, size_t size, 664 struct sg_table *sgt, enum dma_data_direction dir) 665 { 666 const struct dma_map_ops *ops = get_dma_ops(dev); 667 668 debug_dma_unmap_sg(dev, sgt->sgl, sgt->orig_nents, dir); 669 if (ops && ops->free_noncontiguous) 670 ops->free_noncontiguous(dev, size, sgt, dir); 671 else 672 free_single_sgt(dev, size, sgt, dir); 673 } 674 EXPORT_SYMBOL_GPL(dma_free_noncontiguous); 675 676 void *dma_vmap_noncontiguous(struct device *dev, size_t size, 677 struct sg_table *sgt) 678 { 679 const struct dma_map_ops *ops = get_dma_ops(dev); 680 unsigned long count = PAGE_ALIGN(size) >> PAGE_SHIFT; 681 682 if (ops && ops->alloc_noncontiguous) 683 return vmap(sgt_handle(sgt)->pages, count, VM_MAP, PAGE_KERNEL); 684 return page_address(sg_page(sgt->sgl)); 685 } 686 EXPORT_SYMBOL_GPL(dma_vmap_noncontiguous); 687 688 void dma_vunmap_noncontiguous(struct device *dev, void *vaddr) 689 { 690 const struct dma_map_ops *ops = get_dma_ops(dev); 691 692 if (ops && ops->alloc_noncontiguous) 693 vunmap(vaddr); 694 } 695 EXPORT_SYMBOL_GPL(dma_vunmap_noncontiguous); 696 697 int dma_mmap_noncontiguous(struct device *dev, struct vm_area_struct *vma, 698 size_t size, struct sg_table *sgt) 699 { 700 const struct dma_map_ops *ops = get_dma_ops(dev); 701 702 if (ops && ops->alloc_noncontiguous) { 703 unsigned long count = PAGE_ALIGN(size) >> PAGE_SHIFT; 704 705 if (vma->vm_pgoff >= count || 706 vma_pages(vma) > count - vma->vm_pgoff) 707 return -ENXIO; 708 return vm_map_pages(vma, sgt_handle(sgt)->pages, count); 709 } 710 return dma_mmap_pages(dev, vma, size, sg_page(sgt->sgl)); 711 } 712 EXPORT_SYMBOL_GPL(dma_mmap_noncontiguous); 713 714 static int dma_supported(struct device *dev, u64 mask) 715 { 716 const struct dma_map_ops *ops = get_dma_ops(dev); 717 718 /* 719 * ->dma_supported sets the bypass flag, so we must always call 720 * into the method here unless the device is truly direct mapped. 721 */ 722 if (!ops) 723 return dma_direct_supported(dev, mask); 724 if (!ops->dma_supported) 725 return 1; 726 return ops->dma_supported(dev, mask); 727 } 728 729 bool dma_pci_p2pdma_supported(struct device *dev) 730 { 731 const struct dma_map_ops *ops = get_dma_ops(dev); 732 733 /* if ops is not set, dma direct will be used which supports P2PDMA */ 734 if (!ops) 735 return true; 736 737 /* 738 * Note: dma_ops_bypass is not checked here because P2PDMA should 739 * not be used with dma mapping ops that do not have support even 740 * if the specific device is bypassing them. 741 */ 742 743 return ops->flags & DMA_F_PCI_P2PDMA_SUPPORTED; 744 } 745 EXPORT_SYMBOL_GPL(dma_pci_p2pdma_supported); 746 747 #ifdef CONFIG_ARCH_HAS_DMA_SET_MASK 748 void arch_dma_set_mask(struct device *dev, u64 mask); 749 #else 750 #define arch_dma_set_mask(dev, mask) do { } while (0) 751 #endif 752 753 int dma_set_mask(struct device *dev, u64 mask) 754 { 755 /* 756 * Truncate the mask to the actually supported dma_addr_t width to 757 * avoid generating unsupportable addresses. 758 */ 759 mask = (dma_addr_t)mask; 760 761 if (!dev->dma_mask || !dma_supported(dev, mask)) 762 return -EIO; 763 764 arch_dma_set_mask(dev, mask); 765 *dev->dma_mask = mask; 766 return 0; 767 } 768 EXPORT_SYMBOL(dma_set_mask); 769 770 int dma_set_coherent_mask(struct device *dev, u64 mask) 771 { 772 /* 773 * Truncate the mask to the actually supported dma_addr_t width to 774 * avoid generating unsupportable addresses. 775 */ 776 mask = (dma_addr_t)mask; 777 778 if (!dma_supported(dev, mask)) 779 return -EIO; 780 781 dev->coherent_dma_mask = mask; 782 return 0; 783 } 784 EXPORT_SYMBOL(dma_set_coherent_mask); 785 786 size_t dma_max_mapping_size(struct device *dev) 787 { 788 const struct dma_map_ops *ops = get_dma_ops(dev); 789 size_t size = SIZE_MAX; 790 791 if (dma_map_direct(dev, ops)) 792 size = dma_direct_max_mapping_size(dev); 793 else if (ops && ops->max_mapping_size) 794 size = ops->max_mapping_size(dev); 795 796 return size; 797 } 798 EXPORT_SYMBOL_GPL(dma_max_mapping_size); 799 800 size_t dma_opt_mapping_size(struct device *dev) 801 { 802 const struct dma_map_ops *ops = get_dma_ops(dev); 803 size_t size = SIZE_MAX; 804 805 if (ops && ops->opt_mapping_size) 806 size = ops->opt_mapping_size(); 807 808 return min(dma_max_mapping_size(dev), size); 809 } 810 EXPORT_SYMBOL_GPL(dma_opt_mapping_size); 811 812 bool dma_need_sync(struct device *dev, dma_addr_t dma_addr) 813 { 814 const struct dma_map_ops *ops = get_dma_ops(dev); 815 816 if (dma_map_direct(dev, ops)) 817 return dma_direct_need_sync(dev, dma_addr); 818 return ops->sync_single_for_cpu || ops->sync_single_for_device; 819 } 820 EXPORT_SYMBOL_GPL(dma_need_sync); 821 822 unsigned long dma_get_merge_boundary(struct device *dev) 823 { 824 const struct dma_map_ops *ops = get_dma_ops(dev); 825 826 if (!ops || !ops->get_merge_boundary) 827 return 0; /* can't merge */ 828 829 return ops->get_merge_boundary(dev); 830 } 831 EXPORT_SYMBOL_GPL(dma_get_merge_boundary); 832