linux/include/linux/dma-mapping.h
<<
>>
Prefs
   1/* SPDX-License-Identifier: GPL-2.0 */
   2#ifndef _LINUX_DMA_MAPPING_H
   3#define _LINUX_DMA_MAPPING_H
   4
   5#include <linux/sizes.h>
   6#include <linux/string.h>
   7#include <linux/device.h>
   8#include <linux/err.h>
   9#include <linux/dma-direction.h>
  10#include <linux/scatterlist.h>
  11#include <linux/bug.h>
  12#include <linux/mem_encrypt.h>
  13
  14/**
  15 * List of possible attributes associated with a DMA mapping. The semantics
  16 * of each attribute should be defined in Documentation/core-api/dma-attributes.rst.
  17 */
  18
  19/*
  20 * DMA_ATTR_WEAK_ORDERING: Specifies that reads and writes to the mapping
  21 * may be weakly ordered, that is that reads and writes may pass each other.
  22 */
  23#define DMA_ATTR_WEAK_ORDERING          (1UL << 1)
  24/*
  25 * DMA_ATTR_WRITE_COMBINE: Specifies that writes to the mapping may be
  26 * buffered to improve performance.
  27 */
  28#define DMA_ATTR_WRITE_COMBINE          (1UL << 2)
  29/*
  30 * DMA_ATTR_NO_KERNEL_MAPPING: Lets the platform to avoid creating a kernel
  31 * virtual mapping for the allocated buffer.
  32 */
  33#define DMA_ATTR_NO_KERNEL_MAPPING      (1UL << 4)
  34/*
  35 * DMA_ATTR_SKIP_CPU_SYNC: Allows platform code to skip synchronization of
  36 * the CPU cache for the given buffer assuming that it has been already
  37 * transferred to 'device' domain.
  38 */
  39#define DMA_ATTR_SKIP_CPU_SYNC          (1UL << 5)
  40/*
  41 * DMA_ATTR_FORCE_CONTIGUOUS: Forces contiguous allocation of the buffer
  42 * in physical memory.
  43 */
  44#define DMA_ATTR_FORCE_CONTIGUOUS       (1UL << 6)
  45/*
  46 * DMA_ATTR_ALLOC_SINGLE_PAGES: This is a hint to the DMA-mapping subsystem
  47 * that it's probably not worth the time to try to allocate memory to in a way
  48 * that gives better TLB efficiency.
  49 */
  50#define DMA_ATTR_ALLOC_SINGLE_PAGES     (1UL << 7)
  51/*
  52 * DMA_ATTR_NO_WARN: This tells the DMA-mapping subsystem to suppress
  53 * allocation failure reports (similarly to __GFP_NOWARN).
  54 */
  55#define DMA_ATTR_NO_WARN        (1UL << 8)
  56
  57/*
  58 * DMA_ATTR_PRIVILEGED: used to indicate that the buffer is fully
  59 * accessible at an elevated privilege level (and ideally inaccessible or
  60 * at least read-only at lesser-privileged levels).
  61 */
  62#define DMA_ATTR_PRIVILEGED             (1UL << 9)
  63
  64/*
  65 * A dma_addr_t can hold any valid DMA or bus address for the platform.  It can
  66 * be given to a device to use as a DMA source or target.  It is specific to a
  67 * given device and there may be a translation between the CPU physical address
  68 * space and the bus address space.
  69 *
  70 * DMA_MAPPING_ERROR is the magic error code if a mapping failed.  It should not
  71 * be used directly in drivers, but checked for using dma_mapping_error()
  72 * instead.
  73 */
  74#define DMA_MAPPING_ERROR               (~(dma_addr_t)0)
  75
  76#define DMA_BIT_MASK(n) (((n) == 64) ? ~0ULL : ((1ULL<<(n))-1))
  77
  78#ifdef CONFIG_DMA_API_DEBUG
  79void debug_dma_mapping_error(struct device *dev, dma_addr_t dma_addr);
  80void debug_dma_map_single(struct device *dev, const void *addr,
  81                unsigned long len);
  82#else
  83static inline void debug_dma_mapping_error(struct device *dev,
  84                dma_addr_t dma_addr)
  85{
  86}
  87static inline void debug_dma_map_single(struct device *dev, const void *addr,
  88                unsigned long len)
  89{
  90}
  91#endif /* CONFIG_DMA_API_DEBUG */
  92
  93#ifdef CONFIG_HAS_DMA
  94static inline int dma_mapping_error(struct device *dev, dma_addr_t dma_addr)
  95{
  96        debug_dma_mapping_error(dev, dma_addr);
  97
  98        if (unlikely(dma_addr == DMA_MAPPING_ERROR))
  99                return -ENOMEM;
 100        return 0;
 101}
 102
 103dma_addr_t dma_map_page_attrs(struct device *dev, struct page *page,
 104                size_t offset, size_t size, enum dma_data_direction dir,
 105                unsigned long attrs);
 106void dma_unmap_page_attrs(struct device *dev, dma_addr_t addr, size_t size,
 107                enum dma_data_direction dir, unsigned long attrs);
 108unsigned int dma_map_sg_attrs(struct device *dev, struct scatterlist *sg,
 109                int nents, enum dma_data_direction dir, unsigned long attrs);
 110void dma_unmap_sg_attrs(struct device *dev, struct scatterlist *sg,
 111                                      int nents, enum dma_data_direction dir,
 112                                      unsigned long attrs);
 113int dma_map_sgtable(struct device *dev, struct sg_table *sgt,
 114                enum dma_data_direction dir, unsigned long attrs);
 115dma_addr_t dma_map_resource(struct device *dev, phys_addr_t phys_addr,
 116                size_t size, enum dma_data_direction dir, unsigned long attrs);
 117void dma_unmap_resource(struct device *dev, dma_addr_t addr, size_t size,
 118                enum dma_data_direction dir, unsigned long attrs);
 119void dma_sync_single_for_cpu(struct device *dev, dma_addr_t addr, size_t size,
 120                enum dma_data_direction dir);
 121void dma_sync_single_for_device(struct device *dev, dma_addr_t addr,
 122                size_t size, enum dma_data_direction dir);
 123void dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg,
 124                    int nelems, enum dma_data_direction dir);
 125void dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg,
 126                       int nelems, enum dma_data_direction dir);
 127void *dma_alloc_attrs(struct device *dev, size_t size, dma_addr_t *dma_handle,
 128                gfp_t flag, unsigned long attrs);
 129void dma_free_attrs(struct device *dev, size_t size, void *cpu_addr,
 130                dma_addr_t dma_handle, unsigned long attrs);
 131void *dmam_alloc_attrs(struct device *dev, size_t size, dma_addr_t *dma_handle,
 132                gfp_t gfp, unsigned long attrs);
 133void dmam_free_coherent(struct device *dev, size_t size, void *vaddr,
 134                dma_addr_t dma_handle);
 135int dma_get_sgtable_attrs(struct device *dev, struct sg_table *sgt,
 136                void *cpu_addr, dma_addr_t dma_addr, size_t size,
 137                unsigned long attrs);
 138int dma_mmap_attrs(struct device *dev, struct vm_area_struct *vma,
 139                void *cpu_addr, dma_addr_t dma_addr, size_t size,
 140                unsigned long attrs);
 141bool dma_can_mmap(struct device *dev);
 142int dma_supported(struct device *dev, u64 mask);
 143int dma_set_mask(struct device *dev, u64 mask);
 144int dma_set_coherent_mask(struct device *dev, u64 mask);
 145u64 dma_get_required_mask(struct device *dev);
 146size_t dma_max_mapping_size(struct device *dev);
 147bool dma_need_sync(struct device *dev, dma_addr_t dma_addr);
 148unsigned long dma_get_merge_boundary(struct device *dev);
 149struct sg_table *dma_alloc_noncontiguous(struct device *dev, size_t size,
 150                enum dma_data_direction dir, gfp_t gfp, unsigned long attrs);
 151void dma_free_noncontiguous(struct device *dev, size_t size,
 152                struct sg_table *sgt, enum dma_data_direction dir);
 153void *dma_vmap_noncontiguous(struct device *dev, size_t size,
 154                struct sg_table *sgt);
 155void dma_vunmap_noncontiguous(struct device *dev, void *vaddr);
 156int dma_mmap_noncontiguous(struct device *dev, struct vm_area_struct *vma,
 157                size_t size, struct sg_table *sgt);
 158#else /* CONFIG_HAS_DMA */
 159static inline dma_addr_t dma_map_page_attrs(struct device *dev,
 160                struct page *page, size_t offset, size_t size,
 161                enum dma_data_direction dir, unsigned long attrs)
 162{
 163        return DMA_MAPPING_ERROR;
 164}
 165static inline void dma_unmap_page_attrs(struct device *dev, dma_addr_t addr,
 166                size_t size, enum dma_data_direction dir, unsigned long attrs)
 167{
 168}
 169static inline unsigned int dma_map_sg_attrs(struct device *dev,
 170                struct scatterlist *sg, int nents, enum dma_data_direction dir,
 171                unsigned long attrs)
 172{
 173        return 0;
 174}
 175static inline void dma_unmap_sg_attrs(struct device *dev,
 176                struct scatterlist *sg, int nents, enum dma_data_direction dir,
 177                unsigned long attrs)
 178{
 179}
 180static inline int dma_map_sgtable(struct device *dev, struct sg_table *sgt,
 181                enum dma_data_direction dir, unsigned long attrs)
 182{
 183        return -EOPNOTSUPP;
 184}
 185static inline dma_addr_t dma_map_resource(struct device *dev,
 186                phys_addr_t phys_addr, size_t size, enum dma_data_direction dir,
 187                unsigned long attrs)
 188{
 189        return DMA_MAPPING_ERROR;
 190}
 191static inline void dma_unmap_resource(struct device *dev, dma_addr_t addr,
 192                size_t size, enum dma_data_direction dir, unsigned long attrs)
 193{
 194}
 195static inline void dma_sync_single_for_cpu(struct device *dev, dma_addr_t addr,
 196                size_t size, enum dma_data_direction dir)
 197{
 198}
 199static inline void dma_sync_single_for_device(struct device *dev,
 200                dma_addr_t addr, size_t size, enum dma_data_direction dir)
 201{
 202}
 203static inline void dma_sync_sg_for_cpu(struct device *dev,
 204                struct scatterlist *sg, int nelems, enum dma_data_direction dir)
 205{
 206}
 207static inline void dma_sync_sg_for_device(struct device *dev,
 208                struct scatterlist *sg, int nelems, enum dma_data_direction dir)
 209{
 210}
 211static inline int dma_mapping_error(struct device *dev, dma_addr_t dma_addr)
 212{
 213        return -ENOMEM;
 214}
 215static inline void *dma_alloc_attrs(struct device *dev, size_t size,
 216                dma_addr_t *dma_handle, gfp_t flag, unsigned long attrs)
 217{
 218        return NULL;
 219}
 220static void dma_free_attrs(struct device *dev, size_t size, void *cpu_addr,
 221                dma_addr_t dma_handle, unsigned long attrs)
 222{
 223}
 224static inline void *dmam_alloc_attrs(struct device *dev, size_t size,
 225                dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs)
 226{
 227        return NULL;
 228}
 229static inline void dmam_free_coherent(struct device *dev, size_t size,
 230                void *vaddr, dma_addr_t dma_handle)
 231{
 232}
 233static inline int dma_get_sgtable_attrs(struct device *dev,
 234                struct sg_table *sgt, void *cpu_addr, dma_addr_t dma_addr,
 235                size_t size, unsigned long attrs)
 236{
 237        return -ENXIO;
 238}
 239static inline int dma_mmap_attrs(struct device *dev, struct vm_area_struct *vma,
 240                void *cpu_addr, dma_addr_t dma_addr, size_t size,
 241                unsigned long attrs)
 242{
 243        return -ENXIO;
 244}
 245static inline bool dma_can_mmap(struct device *dev)
 246{
 247        return false;
 248}
 249static inline int dma_supported(struct device *dev, u64 mask)
 250{
 251        return 0;
 252}
 253static inline int dma_set_mask(struct device *dev, u64 mask)
 254{
 255        return -EIO;
 256}
 257static inline int dma_set_coherent_mask(struct device *dev, u64 mask)
 258{
 259        return -EIO;
 260}
 261static inline u64 dma_get_required_mask(struct device *dev)
 262{
 263        return 0;
 264}
 265static inline size_t dma_max_mapping_size(struct device *dev)
 266{
 267        return 0;
 268}
 269static inline bool dma_need_sync(struct device *dev, dma_addr_t dma_addr)
 270{
 271        return false;
 272}
 273static inline unsigned long dma_get_merge_boundary(struct device *dev)
 274{
 275        return 0;
 276}
 277static inline struct sg_table *dma_alloc_noncontiguous(struct device *dev,
 278                size_t size, enum dma_data_direction dir, gfp_t gfp,
 279                unsigned long attrs)
 280{
 281        return NULL;
 282}
 283static inline void dma_free_noncontiguous(struct device *dev, size_t size,
 284                struct sg_table *sgt, enum dma_data_direction dir)
 285{
 286}
 287static inline void *dma_vmap_noncontiguous(struct device *dev, size_t size,
 288                struct sg_table *sgt)
 289{
 290        return NULL;
 291}
 292static inline void dma_vunmap_noncontiguous(struct device *dev, void *vaddr)
 293{
 294}
 295static inline int dma_mmap_noncontiguous(struct device *dev,
 296                struct vm_area_struct *vma, size_t size, struct sg_table *sgt)
 297{
 298        return -EINVAL;
 299}
 300#endif /* CONFIG_HAS_DMA */
 301
 302struct page *dma_alloc_pages(struct device *dev, size_t size,
 303                dma_addr_t *dma_handle, enum dma_data_direction dir, gfp_t gfp);
 304void dma_free_pages(struct device *dev, size_t size, struct page *page,
 305                dma_addr_t dma_handle, enum dma_data_direction dir);
 306int dma_mmap_pages(struct device *dev, struct vm_area_struct *vma,
 307                size_t size, struct page *page);
 308
 309static inline void *dma_alloc_noncoherent(struct device *dev, size_t size,
 310                dma_addr_t *dma_handle, enum dma_data_direction dir, gfp_t gfp)
 311{
 312        struct page *page = dma_alloc_pages(dev, size, dma_handle, dir, gfp);
 313        return page ? page_address(page) : NULL;
 314}
 315
 316static inline void dma_free_noncoherent(struct device *dev, size_t size,
 317                void *vaddr, dma_addr_t dma_handle, enum dma_data_direction dir)
 318{
 319        dma_free_pages(dev, size, virt_to_page(vaddr), dma_handle, dir);
 320}
 321
 322static inline dma_addr_t dma_map_single_attrs(struct device *dev, void *ptr,
 323                size_t size, enum dma_data_direction dir, unsigned long attrs)
 324{
 325        /* DMA must never operate on areas that might be remapped. */
 326        if (dev_WARN_ONCE(dev, is_vmalloc_addr(ptr),
 327                          "rejecting DMA map of vmalloc memory\n"))
 328                return DMA_MAPPING_ERROR;
 329        debug_dma_map_single(dev, ptr, size);
 330        return dma_map_page_attrs(dev, virt_to_page(ptr), offset_in_page(ptr),
 331                        size, dir, attrs);
 332}
 333
 334static inline void dma_unmap_single_attrs(struct device *dev, dma_addr_t addr,
 335                size_t size, enum dma_data_direction dir, unsigned long attrs)
 336{
 337        return dma_unmap_page_attrs(dev, addr, size, dir, attrs);
 338}
 339
 340static inline void dma_sync_single_range_for_cpu(struct device *dev,
 341                dma_addr_t addr, unsigned long offset, size_t size,
 342                enum dma_data_direction dir)
 343{
 344        return dma_sync_single_for_cpu(dev, addr + offset, size, dir);
 345}
 346
 347static inline void dma_sync_single_range_for_device(struct device *dev,
 348                dma_addr_t addr, unsigned long offset, size_t size,
 349                enum dma_data_direction dir)
 350{
 351        return dma_sync_single_for_device(dev, addr + offset, size, dir);
 352}
 353
 354/**
 355 * dma_unmap_sgtable - Unmap the given buffer for DMA
 356 * @dev:        The device for which to perform the DMA operation
 357 * @sgt:        The sg_table object describing the buffer
 358 * @dir:        DMA direction
 359 * @attrs:      Optional DMA attributes for the unmap operation
 360 *
 361 * Unmaps a buffer described by a scatterlist stored in the given sg_table
 362 * object for the @dir DMA operation by the @dev device. After this function
 363 * the ownership of the buffer is transferred back to the CPU domain.
 364 */
 365static inline void dma_unmap_sgtable(struct device *dev, struct sg_table *sgt,
 366                enum dma_data_direction dir, unsigned long attrs)
 367{
 368        dma_unmap_sg_attrs(dev, sgt->sgl, sgt->orig_nents, dir, attrs);
 369}
 370
 371/**
 372 * dma_sync_sgtable_for_cpu - Synchronize the given buffer for CPU access
 373 * @dev:        The device for which to perform the DMA operation
 374 * @sgt:        The sg_table object describing the buffer
 375 * @dir:        DMA direction
 376 *
 377 * Performs the needed cache synchronization and moves the ownership of the
 378 * buffer back to the CPU domain, so it is safe to perform any access to it
 379 * by the CPU. Before doing any further DMA operations, one has to transfer
 380 * the ownership of the buffer back to the DMA domain by calling the
 381 * dma_sync_sgtable_for_device().
 382 */
 383static inline void dma_sync_sgtable_for_cpu(struct device *dev,
 384                struct sg_table *sgt, enum dma_data_direction dir)
 385{
 386        dma_sync_sg_for_cpu(dev, sgt->sgl, sgt->orig_nents, dir);
 387}
 388
 389/**
 390 * dma_sync_sgtable_for_device - Synchronize the given buffer for DMA
 391 * @dev:        The device for which to perform the DMA operation
 392 * @sgt:        The sg_table object describing the buffer
 393 * @dir:        DMA direction
 394 *
 395 * Performs the needed cache synchronization and moves the ownership of the
 396 * buffer back to the DMA domain, so it is safe to perform the DMA operation.
 397 * Once finished, one has to call dma_sync_sgtable_for_cpu() or
 398 * dma_unmap_sgtable().
 399 */
 400static inline void dma_sync_sgtable_for_device(struct device *dev,
 401                struct sg_table *sgt, enum dma_data_direction dir)
 402{
 403        dma_sync_sg_for_device(dev, sgt->sgl, sgt->orig_nents, dir);
 404}
 405
 406#define dma_map_single(d, a, s, r) dma_map_single_attrs(d, a, s, r, 0)
 407#define dma_unmap_single(d, a, s, r) dma_unmap_single_attrs(d, a, s, r, 0)
 408#define dma_map_sg(d, s, n, r) dma_map_sg_attrs(d, s, n, r, 0)
 409#define dma_unmap_sg(d, s, n, r) dma_unmap_sg_attrs(d, s, n, r, 0)
 410#define dma_map_page(d, p, o, s, r) dma_map_page_attrs(d, p, o, s, r, 0)
 411#define dma_unmap_page(d, a, s, r) dma_unmap_page_attrs(d, a, s, r, 0)
 412#define dma_get_sgtable(d, t, v, h, s) dma_get_sgtable_attrs(d, t, v, h, s, 0)
 413#define dma_mmap_coherent(d, v, c, h, s) dma_mmap_attrs(d, v, c, h, s, 0)
 414
 415static inline void *dma_alloc_coherent(struct device *dev, size_t size,
 416                dma_addr_t *dma_handle, gfp_t gfp)
 417{
 418        return dma_alloc_attrs(dev, size, dma_handle, gfp,
 419                        (gfp & __GFP_NOWARN) ? DMA_ATTR_NO_WARN : 0);
 420}
 421
 422static inline void dma_free_coherent(struct device *dev, size_t size,
 423                void *cpu_addr, dma_addr_t dma_handle)
 424{
 425        return dma_free_attrs(dev, size, cpu_addr, dma_handle, 0);
 426}
 427
 428
 429static inline u64 dma_get_mask(struct device *dev)
 430{
 431        if (dev->dma_mask && *dev->dma_mask)
 432                return *dev->dma_mask;
 433        return DMA_BIT_MASK(32);
 434}
 435
 436/*
 437 * Set both the DMA mask and the coherent DMA mask to the same thing.
 438 * Note that we don't check the return value from dma_set_coherent_mask()
 439 * as the DMA API guarantees that the coherent DMA mask can be set to
 440 * the same or smaller than the streaming DMA mask.
 441 */
 442static inline int dma_set_mask_and_coherent(struct device *dev, u64 mask)
 443{
 444        int rc = dma_set_mask(dev, mask);
 445        if (rc == 0)
 446                dma_set_coherent_mask(dev, mask);
 447        return rc;
 448}
 449
 450/*
 451 * Similar to the above, except it deals with the case where the device
 452 * does not have dev->dma_mask appropriately setup.
 453 */
 454static inline int dma_coerce_mask_and_coherent(struct device *dev, u64 mask)
 455{
 456        dev->dma_mask = &dev->coherent_dma_mask;
 457        return dma_set_mask_and_coherent(dev, mask);
 458}
 459
 460/**
 461 * dma_addressing_limited - return if the device is addressing limited
 462 * @dev:        device to check
 463 *
 464 * Return %true if the devices DMA mask is too small to address all memory in
 465 * the system, else %false.  Lack of addressing bits is the prime reason for
 466 * bounce buffering, but might not be the only one.
 467 */
 468static inline bool dma_addressing_limited(struct device *dev)
 469{
 470        return min_not_zero(dma_get_mask(dev), dev->bus_dma_limit) <
 471                            dma_get_required_mask(dev);
 472}
 473
 474static inline unsigned int dma_get_max_seg_size(struct device *dev)
 475{
 476        if (dev->dma_parms && dev->dma_parms->max_segment_size)
 477                return dev->dma_parms->max_segment_size;
 478        return SZ_64K;
 479}
 480
 481static inline int dma_set_max_seg_size(struct device *dev, unsigned int size)
 482{
 483        if (dev->dma_parms) {
 484                dev->dma_parms->max_segment_size = size;
 485                return 0;
 486        }
 487        return -EIO;
 488}
 489
 490static inline unsigned long dma_get_seg_boundary(struct device *dev)
 491{
 492        if (dev->dma_parms && dev->dma_parms->segment_boundary_mask)
 493                return dev->dma_parms->segment_boundary_mask;
 494        return ULONG_MAX;
 495}
 496
 497/**
 498 * dma_get_seg_boundary_nr_pages - return the segment boundary in "page" units
 499 * @dev: device to guery the boundary for
 500 * @page_shift: ilog() of the IOMMU page size
 501 *
 502 * Return the segment boundary in IOMMU page units (which may be different from
 503 * the CPU page size) for the passed in device.
 504 *
 505 * If @dev is NULL a boundary of U32_MAX is assumed, this case is just for
 506 * non-DMA API callers.
 507 */
 508static inline unsigned long dma_get_seg_boundary_nr_pages(struct device *dev,
 509                unsigned int page_shift)
 510{
 511        if (!dev)
 512                return (U32_MAX >> page_shift) + 1;
 513        return (dma_get_seg_boundary(dev) >> page_shift) + 1;
 514}
 515
 516static inline int dma_set_seg_boundary(struct device *dev, unsigned long mask)
 517{
 518        if (dev->dma_parms) {
 519                dev->dma_parms->segment_boundary_mask = mask;
 520                return 0;
 521        }
 522        return -EIO;
 523}
 524
 525static inline unsigned int dma_get_min_align_mask(struct device *dev)
 526{
 527        if (dev->dma_parms)
 528                return dev->dma_parms->min_align_mask;
 529        return 0;
 530}
 531
 532static inline int dma_set_min_align_mask(struct device *dev,
 533                unsigned int min_align_mask)
 534{
 535        if (WARN_ON_ONCE(!dev->dma_parms))
 536                return -EIO;
 537        dev->dma_parms->min_align_mask = min_align_mask;
 538        return 0;
 539}
 540
 541static inline int dma_get_cache_alignment(void)
 542{
 543#ifdef ARCH_DMA_MINALIGN
 544        return ARCH_DMA_MINALIGN;
 545#endif
 546        return 1;
 547}
 548
 549static inline void *dmam_alloc_coherent(struct device *dev, size_t size,
 550                dma_addr_t *dma_handle, gfp_t gfp)
 551{
 552        return dmam_alloc_attrs(dev, size, dma_handle, gfp,
 553                        (gfp & __GFP_NOWARN) ? DMA_ATTR_NO_WARN : 0);
 554}
 555
 556static inline void *dma_alloc_wc(struct device *dev, size_t size,
 557                                 dma_addr_t *dma_addr, gfp_t gfp)
 558{
 559        unsigned long attrs = DMA_ATTR_WRITE_COMBINE;
 560
 561        if (gfp & __GFP_NOWARN)
 562                attrs |= DMA_ATTR_NO_WARN;
 563
 564        return dma_alloc_attrs(dev, size, dma_addr, gfp, attrs);
 565}
 566
 567static inline void dma_free_wc(struct device *dev, size_t size,
 568                               void *cpu_addr, dma_addr_t dma_addr)
 569{
 570        return dma_free_attrs(dev, size, cpu_addr, dma_addr,
 571                              DMA_ATTR_WRITE_COMBINE);
 572}
 573
 574static inline int dma_mmap_wc(struct device *dev,
 575                              struct vm_area_struct *vma,
 576                              void *cpu_addr, dma_addr_t dma_addr,
 577                              size_t size)
 578{
 579        return dma_mmap_attrs(dev, vma, cpu_addr, dma_addr, size,
 580                              DMA_ATTR_WRITE_COMBINE);
 581}
 582
 583#ifdef CONFIG_NEED_DMA_MAP_STATE
 584#define DEFINE_DMA_UNMAP_ADDR(ADDR_NAME)        dma_addr_t ADDR_NAME
 585#define DEFINE_DMA_UNMAP_LEN(LEN_NAME)          __u32 LEN_NAME
 586#define dma_unmap_addr(PTR, ADDR_NAME)           ((PTR)->ADDR_NAME)
 587#define dma_unmap_addr_set(PTR, ADDR_NAME, VAL)  (((PTR)->ADDR_NAME) = (VAL))
 588#define dma_unmap_len(PTR, LEN_NAME)             ((PTR)->LEN_NAME)
 589#define dma_unmap_len_set(PTR, LEN_NAME, VAL)    (((PTR)->LEN_NAME) = (VAL))
 590#else
 591#define DEFINE_DMA_UNMAP_ADDR(ADDR_NAME)
 592#define DEFINE_DMA_UNMAP_LEN(LEN_NAME)
 593#define dma_unmap_addr(PTR, ADDR_NAME)           (0)
 594#define dma_unmap_addr_set(PTR, ADDR_NAME, VAL)  do { } while (0)
 595#define dma_unmap_len(PTR, LEN_NAME)             (0)
 596#define dma_unmap_len_set(PTR, LEN_NAME, VAL)    do { } while (0)
 597#endif
 598
 599#endif /* _LINUX_DMA_MAPPING_H */
 600