linux/include/linux/dma-mapping.h
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   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);
 108int dma_map_sg_attrs(struct device *dev, struct scatterlist *sg, int nents,
 109                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);
 113dma_addr_t dma_map_resource(struct device *dev, phys_addr_t phys_addr,
 114                size_t size, enum dma_data_direction dir, unsigned long attrs);
 115void dma_unmap_resource(struct device *dev, dma_addr_t addr, size_t size,
 116                enum dma_data_direction dir, unsigned long attrs);
 117void dma_sync_single_for_cpu(struct device *dev, dma_addr_t addr, size_t size,
 118                enum dma_data_direction dir);
 119void dma_sync_single_for_device(struct device *dev, dma_addr_t addr,
 120                size_t size, enum dma_data_direction dir);
 121void dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg,
 122                    int nelems, enum dma_data_direction dir);
 123void dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg,
 124                       int nelems, enum dma_data_direction dir);
 125void *dma_alloc_attrs(struct device *dev, size_t size, dma_addr_t *dma_handle,
 126                gfp_t flag, unsigned long attrs);
 127void dma_free_attrs(struct device *dev, size_t size, void *cpu_addr,
 128                dma_addr_t dma_handle, unsigned long attrs);
 129void *dmam_alloc_attrs(struct device *dev, size_t size, dma_addr_t *dma_handle,
 130                gfp_t gfp, unsigned long attrs);
 131void dmam_free_coherent(struct device *dev, size_t size, void *vaddr,
 132                dma_addr_t dma_handle);
 133int dma_get_sgtable_attrs(struct device *dev, struct sg_table *sgt,
 134                void *cpu_addr, dma_addr_t dma_addr, size_t size,
 135                unsigned long attrs);
 136int dma_mmap_attrs(struct device *dev, struct vm_area_struct *vma,
 137                void *cpu_addr, dma_addr_t dma_addr, size_t size,
 138                unsigned long attrs);
 139bool dma_can_mmap(struct device *dev);
 140int dma_supported(struct device *dev, u64 mask);
 141int dma_set_mask(struct device *dev, u64 mask);
 142int dma_set_coherent_mask(struct device *dev, u64 mask);
 143u64 dma_get_required_mask(struct device *dev);
 144size_t dma_max_mapping_size(struct device *dev);
 145bool dma_need_sync(struct device *dev, dma_addr_t dma_addr);
 146unsigned long dma_get_merge_boundary(struct device *dev);
 147struct sg_table *dma_alloc_noncontiguous(struct device *dev, size_t size,
 148                enum dma_data_direction dir, gfp_t gfp, unsigned long attrs);
 149void dma_free_noncontiguous(struct device *dev, size_t size,
 150                struct sg_table *sgt, enum dma_data_direction dir);
 151void *dma_vmap_noncontiguous(struct device *dev, size_t size,
 152                struct sg_table *sgt);
 153void dma_vunmap_noncontiguous(struct device *dev, void *vaddr);
 154int dma_mmap_noncontiguous(struct device *dev, struct vm_area_struct *vma,
 155                size_t size, struct sg_table *sgt);
 156#else /* CONFIG_HAS_DMA */
 157static inline dma_addr_t dma_map_page_attrs(struct device *dev,
 158                struct page *page, size_t offset, size_t size,
 159                enum dma_data_direction dir, unsigned long attrs)
 160{
 161        return DMA_MAPPING_ERROR;
 162}
 163static inline void dma_unmap_page_attrs(struct device *dev, dma_addr_t addr,
 164                size_t size, enum dma_data_direction dir, unsigned long attrs)
 165{
 166}
 167static inline int dma_map_sg_attrs(struct device *dev, struct scatterlist *sg,
 168                int nents, enum dma_data_direction dir, unsigned long attrs)
 169{
 170        return 0;
 171}
 172static inline void dma_unmap_sg_attrs(struct device *dev,
 173                struct scatterlist *sg, int nents, enum dma_data_direction dir,
 174                unsigned long attrs)
 175{
 176}
 177static inline dma_addr_t dma_map_resource(struct device *dev,
 178                phys_addr_t phys_addr, size_t size, enum dma_data_direction dir,
 179                unsigned long attrs)
 180{
 181        return DMA_MAPPING_ERROR;
 182}
 183static inline void dma_unmap_resource(struct device *dev, dma_addr_t addr,
 184                size_t size, enum dma_data_direction dir, unsigned long attrs)
 185{
 186}
 187static inline void dma_sync_single_for_cpu(struct device *dev, dma_addr_t addr,
 188                size_t size, enum dma_data_direction dir)
 189{
 190}
 191static inline void dma_sync_single_for_device(struct device *dev,
 192                dma_addr_t addr, size_t size, enum dma_data_direction dir)
 193{
 194}
 195static inline void dma_sync_sg_for_cpu(struct device *dev,
 196                struct scatterlist *sg, int nelems, enum dma_data_direction dir)
 197{
 198}
 199static inline void dma_sync_sg_for_device(struct device *dev,
 200                struct scatterlist *sg, int nelems, enum dma_data_direction dir)
 201{
 202}
 203static inline int dma_mapping_error(struct device *dev, dma_addr_t dma_addr)
 204{
 205        return -ENOMEM;
 206}
 207static inline void *dma_alloc_attrs(struct device *dev, size_t size,
 208                dma_addr_t *dma_handle, gfp_t flag, unsigned long attrs)
 209{
 210        return NULL;
 211}
 212static void dma_free_attrs(struct device *dev, size_t size, void *cpu_addr,
 213                dma_addr_t dma_handle, unsigned long attrs)
 214{
 215}
 216static inline void *dmam_alloc_attrs(struct device *dev, size_t size,
 217                dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs)
 218{
 219        return NULL;
 220}
 221static inline void dmam_free_coherent(struct device *dev, size_t size,
 222                void *vaddr, dma_addr_t dma_handle)
 223{
 224}
 225static inline int dma_get_sgtable_attrs(struct device *dev,
 226                struct sg_table *sgt, void *cpu_addr, dma_addr_t dma_addr,
 227                size_t size, unsigned long attrs)
 228{
 229        return -ENXIO;
 230}
 231static inline int dma_mmap_attrs(struct device *dev, struct vm_area_struct *vma,
 232                void *cpu_addr, dma_addr_t dma_addr, size_t size,
 233                unsigned long attrs)
 234{
 235        return -ENXIO;
 236}
 237static inline bool dma_can_mmap(struct device *dev)
 238{
 239        return false;
 240}
 241static inline int dma_supported(struct device *dev, u64 mask)
 242{
 243        return 0;
 244}
 245static inline int dma_set_mask(struct device *dev, u64 mask)
 246{
 247        return -EIO;
 248}
 249static inline int dma_set_coherent_mask(struct device *dev, u64 mask)
 250{
 251        return -EIO;
 252}
 253static inline u64 dma_get_required_mask(struct device *dev)
 254{
 255        return 0;
 256}
 257static inline size_t dma_max_mapping_size(struct device *dev)
 258{
 259        return 0;
 260}
 261static inline bool dma_need_sync(struct device *dev, dma_addr_t dma_addr)
 262{
 263        return false;
 264}
 265static inline unsigned long dma_get_merge_boundary(struct device *dev)
 266{
 267        return 0;
 268}
 269static inline struct sg_table *dma_alloc_noncontiguous(struct device *dev,
 270                size_t size, enum dma_data_direction dir, gfp_t gfp,
 271                unsigned long attrs)
 272{
 273        return NULL;
 274}
 275static inline void dma_free_noncontiguous(struct device *dev, size_t size,
 276                struct sg_table *sgt, enum dma_data_direction dir)
 277{
 278}
 279static inline void *dma_vmap_noncontiguous(struct device *dev, size_t size,
 280                struct sg_table *sgt)
 281{
 282        return NULL;
 283}
 284static inline void dma_vunmap_noncontiguous(struct device *dev, void *vaddr)
 285{
 286}
 287static inline int dma_mmap_noncontiguous(struct device *dev,
 288                struct vm_area_struct *vma, size_t size, struct sg_table *sgt)
 289{
 290        return -EINVAL;
 291}
 292#endif /* CONFIG_HAS_DMA */
 293
 294struct page *dma_alloc_pages(struct device *dev, size_t size,
 295                dma_addr_t *dma_handle, enum dma_data_direction dir, gfp_t gfp);
 296void dma_free_pages(struct device *dev, size_t size, struct page *page,
 297                dma_addr_t dma_handle, enum dma_data_direction dir);
 298int dma_mmap_pages(struct device *dev, struct vm_area_struct *vma,
 299                size_t size, struct page *page);
 300
 301static inline void *dma_alloc_noncoherent(struct device *dev, size_t size,
 302                dma_addr_t *dma_handle, enum dma_data_direction dir, gfp_t gfp)
 303{
 304        struct page *page = dma_alloc_pages(dev, size, dma_handle, dir, gfp);
 305        return page ? page_address(page) : NULL;
 306}
 307
 308static inline void dma_free_noncoherent(struct device *dev, size_t size,
 309                void *vaddr, dma_addr_t dma_handle, enum dma_data_direction dir)
 310{
 311        dma_free_pages(dev, size, virt_to_page(vaddr), dma_handle, dir);
 312}
 313
 314static inline dma_addr_t dma_map_single_attrs(struct device *dev, void *ptr,
 315                size_t size, enum dma_data_direction dir, unsigned long attrs)
 316{
 317        /* DMA must never operate on areas that might be remapped. */
 318        if (dev_WARN_ONCE(dev, is_vmalloc_addr(ptr),
 319                          "rejecting DMA map of vmalloc memory\n"))
 320                return DMA_MAPPING_ERROR;
 321        debug_dma_map_single(dev, ptr, size);
 322        return dma_map_page_attrs(dev, virt_to_page(ptr), offset_in_page(ptr),
 323                        size, dir, attrs);
 324}
 325
 326static inline void dma_unmap_single_attrs(struct device *dev, dma_addr_t addr,
 327                size_t size, enum dma_data_direction dir, unsigned long attrs)
 328{
 329        return dma_unmap_page_attrs(dev, addr, size, dir, attrs);
 330}
 331
 332static inline void dma_sync_single_range_for_cpu(struct device *dev,
 333                dma_addr_t addr, unsigned long offset, size_t size,
 334                enum dma_data_direction dir)
 335{
 336        return dma_sync_single_for_cpu(dev, addr + offset, size, dir);
 337}
 338
 339static inline void dma_sync_single_range_for_device(struct device *dev,
 340                dma_addr_t addr, unsigned long offset, size_t size,
 341                enum dma_data_direction dir)
 342{
 343        return dma_sync_single_for_device(dev, addr + offset, size, dir);
 344}
 345
 346/**
 347 * dma_map_sgtable - Map the given buffer for DMA
 348 * @dev:        The device for which to perform the DMA operation
 349 * @sgt:        The sg_table object describing the buffer
 350 * @dir:        DMA direction
 351 * @attrs:      Optional DMA attributes for the map operation
 352 *
 353 * Maps a buffer described by a scatterlist stored in the given sg_table
 354 * object for the @dir DMA operation by the @dev device. After success the
 355 * ownership for the buffer is transferred to the DMA domain.  One has to
 356 * call dma_sync_sgtable_for_cpu() or dma_unmap_sgtable() to move the
 357 * ownership of the buffer back to the CPU domain before touching the
 358 * buffer by the CPU.
 359 *
 360 * Returns 0 on success or -EINVAL on error during mapping the buffer.
 361 */
 362static inline int dma_map_sgtable(struct device *dev, struct sg_table *sgt,
 363                enum dma_data_direction dir, unsigned long attrs)
 364{
 365        int nents;
 366
 367        nents = dma_map_sg_attrs(dev, sgt->sgl, sgt->orig_nents, dir, attrs);
 368        if (nents <= 0)
 369                return -EINVAL;
 370        sgt->nents = nents;
 371        return 0;
 372}
 373
 374/**
 375 * dma_unmap_sgtable - Unmap the given buffer for DMA
 376 * @dev:        The device for which to perform the DMA operation
 377 * @sgt:        The sg_table object describing the buffer
 378 * @dir:        DMA direction
 379 * @attrs:      Optional DMA attributes for the unmap operation
 380 *
 381 * Unmaps a buffer described by a scatterlist stored in the given sg_table
 382 * object for the @dir DMA operation by the @dev device. After this function
 383 * the ownership of the buffer is transferred back to the CPU domain.
 384 */
 385static inline void dma_unmap_sgtable(struct device *dev, struct sg_table *sgt,
 386                enum dma_data_direction dir, unsigned long attrs)
 387{
 388        dma_unmap_sg_attrs(dev, sgt->sgl, sgt->orig_nents, dir, attrs);
 389}
 390
 391/**
 392 * dma_sync_sgtable_for_cpu - Synchronize the given buffer for CPU access
 393 * @dev:        The device for which to perform the DMA operation
 394 * @sgt:        The sg_table object describing the buffer
 395 * @dir:        DMA direction
 396 *
 397 * Performs the needed cache synchronization and moves the ownership of the
 398 * buffer back to the CPU domain, so it is safe to perform any access to it
 399 * by the CPU. Before doing any further DMA operations, one has to transfer
 400 * the ownership of the buffer back to the DMA domain by calling the
 401 * dma_sync_sgtable_for_device().
 402 */
 403static inline void dma_sync_sgtable_for_cpu(struct device *dev,
 404                struct sg_table *sgt, enum dma_data_direction dir)
 405{
 406        dma_sync_sg_for_cpu(dev, sgt->sgl, sgt->orig_nents, dir);
 407}
 408
 409/**
 410 * dma_sync_sgtable_for_device - Synchronize the given buffer for DMA
 411 * @dev:        The device for which to perform the DMA operation
 412 * @sgt:        The sg_table object describing the buffer
 413 * @dir:        DMA direction
 414 *
 415 * Performs the needed cache synchronization and moves the ownership of the
 416 * buffer back to the DMA domain, so it is safe to perform the DMA operation.
 417 * Once finished, one has to call dma_sync_sgtable_for_cpu() or
 418 * dma_unmap_sgtable().
 419 */
 420static inline void dma_sync_sgtable_for_device(struct device *dev,
 421                struct sg_table *sgt, enum dma_data_direction dir)
 422{
 423        dma_sync_sg_for_device(dev, sgt->sgl, sgt->orig_nents, dir);
 424}
 425
 426#define dma_map_single(d, a, s, r) dma_map_single_attrs(d, a, s, r, 0)
 427#define dma_unmap_single(d, a, s, r) dma_unmap_single_attrs(d, a, s, r, 0)
 428#define dma_map_sg(d, s, n, r) dma_map_sg_attrs(d, s, n, r, 0)
 429#define dma_unmap_sg(d, s, n, r) dma_unmap_sg_attrs(d, s, n, r, 0)
 430#define dma_map_page(d, p, o, s, r) dma_map_page_attrs(d, p, o, s, r, 0)
 431#define dma_unmap_page(d, a, s, r) dma_unmap_page_attrs(d, a, s, r, 0)
 432#define dma_get_sgtable(d, t, v, h, s) dma_get_sgtable_attrs(d, t, v, h, s, 0)
 433#define dma_mmap_coherent(d, v, c, h, s) dma_mmap_attrs(d, v, c, h, s, 0)
 434
 435static inline void *dma_alloc_coherent(struct device *dev, size_t size,
 436                dma_addr_t *dma_handle, gfp_t gfp)
 437{
 438        return dma_alloc_attrs(dev, size, dma_handle, gfp,
 439                        (gfp & __GFP_NOWARN) ? DMA_ATTR_NO_WARN : 0);
 440}
 441
 442static inline void dma_free_coherent(struct device *dev, size_t size,
 443                void *cpu_addr, dma_addr_t dma_handle)
 444{
 445        return dma_free_attrs(dev, size, cpu_addr, dma_handle, 0);
 446}
 447
 448
 449static inline u64 dma_get_mask(struct device *dev)
 450{
 451        if (dev->dma_mask && *dev->dma_mask)
 452                return *dev->dma_mask;
 453        return DMA_BIT_MASK(32);
 454}
 455
 456/*
 457 * Set both the DMA mask and the coherent DMA mask to the same thing.
 458 * Note that we don't check the return value from dma_set_coherent_mask()
 459 * as the DMA API guarantees that the coherent DMA mask can be set to
 460 * the same or smaller than the streaming DMA mask.
 461 */
 462static inline int dma_set_mask_and_coherent(struct device *dev, u64 mask)
 463{
 464        int rc = dma_set_mask(dev, mask);
 465        if (rc == 0)
 466                dma_set_coherent_mask(dev, mask);
 467        return rc;
 468}
 469
 470/*
 471 * Similar to the above, except it deals with the case where the device
 472 * does not have dev->dma_mask appropriately setup.
 473 */
 474static inline int dma_coerce_mask_and_coherent(struct device *dev, u64 mask)
 475{
 476        dev->dma_mask = &dev->coherent_dma_mask;
 477        return dma_set_mask_and_coherent(dev, mask);
 478}
 479
 480/**
 481 * dma_addressing_limited - return if the device is addressing limited
 482 * @dev:        device to check
 483 *
 484 * Return %true if the devices DMA mask is too small to address all memory in
 485 * the system, else %false.  Lack of addressing bits is the prime reason for
 486 * bounce buffering, but might not be the only one.
 487 */
 488static inline bool dma_addressing_limited(struct device *dev)
 489{
 490        return min_not_zero(dma_get_mask(dev), dev->bus_dma_limit) <
 491                            dma_get_required_mask(dev);
 492}
 493
 494static inline unsigned int dma_get_max_seg_size(struct device *dev)
 495{
 496        if (dev->dma_parms && dev->dma_parms->max_segment_size)
 497                return dev->dma_parms->max_segment_size;
 498        return SZ_64K;
 499}
 500
 501static inline int dma_set_max_seg_size(struct device *dev, unsigned int size)
 502{
 503        if (dev->dma_parms) {
 504                dev->dma_parms->max_segment_size = size;
 505                return 0;
 506        }
 507        return -EIO;
 508}
 509
 510static inline unsigned long dma_get_seg_boundary(struct device *dev)
 511{
 512        if (dev->dma_parms && dev->dma_parms->segment_boundary_mask)
 513                return dev->dma_parms->segment_boundary_mask;
 514        return ULONG_MAX;
 515}
 516
 517/**
 518 * dma_get_seg_boundary_nr_pages - return the segment boundary in "page" units
 519 * @dev: device to guery the boundary for
 520 * @page_shift: ilog() of the IOMMU page size
 521 *
 522 * Return the segment boundary in IOMMU page units (which may be different from
 523 * the CPU page size) for the passed in device.
 524 *
 525 * If @dev is NULL a boundary of U32_MAX is assumed, this case is just for
 526 * non-DMA API callers.
 527 */
 528static inline unsigned long dma_get_seg_boundary_nr_pages(struct device *dev,
 529                unsigned int page_shift)
 530{
 531        if (!dev)
 532                return (U32_MAX >> page_shift) + 1;
 533        return (dma_get_seg_boundary(dev) >> page_shift) + 1;
 534}
 535
 536static inline int dma_set_seg_boundary(struct device *dev, unsigned long mask)
 537{
 538        if (dev->dma_parms) {
 539                dev->dma_parms->segment_boundary_mask = mask;
 540                return 0;
 541        }
 542        return -EIO;
 543}
 544
 545static inline unsigned int dma_get_min_align_mask(struct device *dev)
 546{
 547        if (dev->dma_parms)
 548                return dev->dma_parms->min_align_mask;
 549        return 0;
 550}
 551
 552static inline int dma_set_min_align_mask(struct device *dev,
 553                unsigned int min_align_mask)
 554{
 555        if (WARN_ON_ONCE(!dev->dma_parms))
 556                return -EIO;
 557        dev->dma_parms->min_align_mask = min_align_mask;
 558        return 0;
 559}
 560
 561static inline int dma_get_cache_alignment(void)
 562{
 563#ifdef ARCH_DMA_MINALIGN
 564        return ARCH_DMA_MINALIGN;
 565#endif
 566        return 1;
 567}
 568
 569static inline void *dmam_alloc_coherent(struct device *dev, size_t size,
 570                dma_addr_t *dma_handle, gfp_t gfp)
 571{
 572        return dmam_alloc_attrs(dev, size, dma_handle, gfp,
 573                        (gfp & __GFP_NOWARN) ? DMA_ATTR_NO_WARN : 0);
 574}
 575
 576static inline void *dma_alloc_wc(struct device *dev, size_t size,
 577                                 dma_addr_t *dma_addr, gfp_t gfp)
 578{
 579        unsigned long attrs = DMA_ATTR_WRITE_COMBINE;
 580
 581        if (gfp & __GFP_NOWARN)
 582                attrs |= DMA_ATTR_NO_WARN;
 583
 584        return dma_alloc_attrs(dev, size, dma_addr, gfp, attrs);
 585}
 586
 587static inline void dma_free_wc(struct device *dev, size_t size,
 588                               void *cpu_addr, dma_addr_t dma_addr)
 589{
 590        return dma_free_attrs(dev, size, cpu_addr, dma_addr,
 591                              DMA_ATTR_WRITE_COMBINE);
 592}
 593
 594static inline int dma_mmap_wc(struct device *dev,
 595                              struct vm_area_struct *vma,
 596                              void *cpu_addr, dma_addr_t dma_addr,
 597                              size_t size)
 598{
 599        return dma_mmap_attrs(dev, vma, cpu_addr, dma_addr, size,
 600                              DMA_ATTR_WRITE_COMBINE);
 601}
 602
 603#ifdef CONFIG_NEED_DMA_MAP_STATE
 604#define DEFINE_DMA_UNMAP_ADDR(ADDR_NAME)        dma_addr_t ADDR_NAME
 605#define DEFINE_DMA_UNMAP_LEN(LEN_NAME)          __u32 LEN_NAME
 606#define dma_unmap_addr(PTR, ADDR_NAME)           ((PTR)->ADDR_NAME)
 607#define dma_unmap_addr_set(PTR, ADDR_NAME, VAL)  (((PTR)->ADDR_NAME) = (VAL))
 608#define dma_unmap_len(PTR, LEN_NAME)             ((PTR)->LEN_NAME)
 609#define dma_unmap_len_set(PTR, LEN_NAME, VAL)    (((PTR)->LEN_NAME) = (VAL))
 610#else
 611#define DEFINE_DMA_UNMAP_ADDR(ADDR_NAME)
 612#define DEFINE_DMA_UNMAP_LEN(LEN_NAME)
 613#define dma_unmap_addr(PTR, ADDR_NAME)           (0)
 614#define dma_unmap_addr_set(PTR, ADDR_NAME, VAL)  do { } while (0)
 615#define dma_unmap_len(PTR, LEN_NAME)             (0)
 616#define dma_unmap_len_set(PTR, LEN_NAME, VAL)    do { } while (0)
 617#endif
 618
 619#endif /* _LINUX_DMA_MAPPING_H */
 620