include/linux/dma-mapping.h

   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
  79 void debug_dma_mapping_error(struct device *dev, dma_addr_t dma_addr);
  80 void debug_dma_map_single(struct device *dev, const void *addr,
  81                 unsigned long len);
  82 #else
  83 static inline void debug_dma_mapping_error(struct device *dev,
  84                 dma_addr_t dma_addr)
  85 {
  86 }
  87 static 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
  94 static 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 (dma_addr == DMA_MAPPING_ERROR)
  99                 return -ENOMEM;
 100         return 0;
 101 }
 102
 103 dma_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);
 106 void dma_unmap_page_attrs(struct device *dev, dma_addr_t addr, size_t size,
 107                 enum dma_data_direction dir, unsigned long attrs);
 108 int dma_map_sg_attrs(struct device *dev, struct scatterlist *sg, int nents,
 109                 enum dma_data_direction dir, unsigned long attrs);
 110 void dma_unmap_sg_attrs(struct device *dev, struct scatterlist *sg,
 111                                       int nents, enum dma_data_direction dir,
 112                                       unsigned long attrs);
 113 dma_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);
 115 void dma_unmap_resource(struct device *dev, dma_addr_t addr, size_t size,
 116                 enum dma_data_direction dir, unsigned long attrs);
 117 void dma_sync_single_for_cpu(struct device *dev, dma_addr_t addr, size_t size,
 118                 enum dma_data_direction dir);
 119 void dma_sync_single_for_device(struct device *dev, dma_addr_t addr,
 120                 size_t size, enum dma_data_direction dir);
 121 void dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg,
 122                     int nelems, enum dma_data_direction dir);
 123 void dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg,
 124                        int nelems, enum dma_data_direction dir);
 125 void *dma_alloc_attrs(struct device *dev, size_t size, dma_addr_t *dma_handle,
 126                 gfp_t flag, unsigned long attrs);
 127 void dma_free_attrs(struct device *dev, size_t size, void *cpu_addr,
 128                 dma_addr_t dma_handle, unsigned long attrs);
 129 void *dmam_alloc_attrs(struct device *dev, size_t size, dma_addr_t *dma_handle,
 130                 gfp_t gfp, unsigned long attrs);
 131 void dmam_free_coherent(struct device *dev, size_t size, void *vaddr,
 132                 dma_addr_t dma_handle);
 133 int 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);
 136 int 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);
 139 bool dma_can_mmap(struct device *dev);
 140 int dma_supported(struct device *dev, u64 mask);
 141 int dma_set_mask(struct device *dev, u64 mask);
 142 int dma_set_coherent_mask(struct device *dev, u64 mask);
 143 u64 dma_get_required_mask(struct device *dev);
 144 size_t dma_max_mapping_size(struct device *dev);
 145 bool dma_need_sync(struct device *dev, dma_addr_t dma_addr);
 146 unsigned long dma_get_merge_boundary(struct device *dev);
 147 #else /* CONFIG_HAS_DMA */
 148 static inline dma_addr_t dma_map_page_attrs(struct device *dev,
 149                 struct page *page, size_t offset, size_t size,
 150                 enum dma_data_direction dir, unsigned long attrs)
 151 {
 152         return DMA_MAPPING_ERROR;
 153 }
 154 static inline void dma_unmap_page_attrs(struct device *dev, dma_addr_t addr,
 155                 size_t size, enum dma_data_direction dir, unsigned long attrs)
 156 {
 157 }
 158 static inline int dma_map_sg_attrs(struct device *dev, struct scatterlist *sg,
 159                 int nents, enum dma_data_direction dir, unsigned long attrs)
 160 {
 161         return 0;
 162 }
 163 static inline void dma_unmap_sg_attrs(struct device *dev,
 164                 struct scatterlist *sg, int nents, enum dma_data_direction dir,
 165                 unsigned long attrs)
 166 {
 167 }
 168 static inline dma_addr_t dma_map_resource(struct device *dev,
 169                 phys_addr_t phys_addr, size_t size, enum dma_data_direction dir,
 170                 unsigned long attrs)
 171 {
 172         return DMA_MAPPING_ERROR;
 173 }
 174 static inline void dma_unmap_resource(struct device *dev, dma_addr_t addr,
 175                 size_t size, enum dma_data_direction dir, unsigned long attrs)
 176 {
 177 }
 178 static inline void dma_sync_single_for_cpu(struct device *dev, dma_addr_t addr,
 179                 size_t size, enum dma_data_direction dir)
 180 {
 181 }
 182 static inline void dma_sync_single_for_device(struct device *dev,
 183                 dma_addr_t addr, size_t size, enum dma_data_direction dir)
 184 {
 185 }
 186 static inline void dma_sync_sg_for_cpu(struct device *dev,
 187                 struct scatterlist *sg, int nelems, enum dma_data_direction dir)
 188 {
 189 }
 190 static inline void dma_sync_sg_for_device(struct device *dev,
 191                 struct scatterlist *sg, int nelems, enum dma_data_direction dir)
 192 {
 193 }
 194 static inline int dma_mapping_error(struct device *dev, dma_addr_t dma_addr)
 195 {
 196         return -ENOMEM;
 197 }
 198 static inline void *dma_alloc_attrs(struct device *dev, size_t size,
 199                 dma_addr_t *dma_handle, gfp_t flag, unsigned long attrs)
 200 {
 201         return NULL;
 202 }
 203 static void dma_free_attrs(struct device *dev, size_t size, void *cpu_addr,
 204                 dma_addr_t dma_handle, unsigned long attrs)
 205 {
 206 }
 207 static inline void *dmam_alloc_attrs(struct device *dev, size_t size,
 208                 dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs)
 209 {
 210         return NULL;
 211 }
 212 static inline void dmam_free_coherent(struct device *dev, size_t size,
 213                 void *vaddr, dma_addr_t dma_handle)
 214 {
 215 }
 216 static inline int dma_get_sgtable_attrs(struct device *dev,
 217                 struct sg_table *sgt, void *cpu_addr, dma_addr_t dma_addr,
 218                 size_t size, unsigned long attrs)
 219 {
 220         return -ENXIO;
 221 }
 222 static inline int dma_mmap_attrs(struct device *dev, struct vm_area_struct *vma,
 223                 void *cpu_addr, dma_addr_t dma_addr, size_t size,
 224                 unsigned long attrs)
 225 {
 226         return -ENXIO;
 227 }
 228 static inline bool dma_can_mmap(struct device *dev)
 229 {
 230         return false;
 231 }
 232 static inline int dma_supported(struct device *dev, u64 mask)
 233 {
 234         return 0;
 235 }
 236 static inline int dma_set_mask(struct device *dev, u64 mask)
 237 {
 238         return -EIO;
 239 }
 240 static inline int dma_set_coherent_mask(struct device *dev, u64 mask)
 241 {
 242         return -EIO;
 243 }
 244 static inline u64 dma_get_required_mask(struct device *dev)
 245 {
 246         return 0;
 247 }
 248 static inline size_t dma_max_mapping_size(struct device *dev)
 249 {
 250         return 0;
 251 }
 252 static inline bool dma_need_sync(struct device *dev, dma_addr_t dma_addr)
 253 {
 254         return false;
 255 }
 256 static inline unsigned long dma_get_merge_boundary(struct device *dev)
 257 {
 258         return 0;
 259 }
 260 #endif /* CONFIG_HAS_DMA */
 261
 262 struct page *dma_alloc_pages(struct device *dev, size_t size,
 263                 dma_addr_t *dma_handle, enum dma_data_direction dir, gfp_t gfp);
 264 void dma_free_pages(struct device *dev, size_t size, struct page *page,
 265                 dma_addr_t dma_handle, enum dma_data_direction dir);
 266 void *dma_alloc_noncoherent(struct device *dev, size_t size,
 267                 dma_addr_t *dma_handle, enum dma_data_direction dir, gfp_t gfp);
 268 void dma_free_noncoherent(struct device *dev, size_t size, void *vaddr,
 269                 dma_addr_t dma_handle, enum dma_data_direction dir);
 270
 271 static inline dma_addr_t dma_map_single_attrs(struct device *dev, void *ptr,
 272                 size_t size, enum dma_data_direction dir, unsigned long attrs)
 273 {
 274         /* DMA must never operate on areas that might be remapped. */
 275         if (dev_WARN_ONCE(dev, is_vmalloc_addr(ptr),
 276                           "rejecting DMA map of vmalloc memory\n"))
 277                 return DMA_MAPPING_ERROR;
 278         debug_dma_map_single(dev, ptr, size);
 279         return dma_map_page_attrs(dev, virt_to_page(ptr), offset_in_page(ptr),
 280                         size, dir, attrs);
 281 }
 282
 283 static inline void dma_unmap_single_attrs(struct device *dev, dma_addr_t addr,
 284                 size_t size, enum dma_data_direction dir, unsigned long attrs)
 285 {
 286         return dma_unmap_page_attrs(dev, addr, size, dir, attrs);
 287 }
 288
 289 static inline void dma_sync_single_range_for_cpu(struct device *dev,
 290                 dma_addr_t addr, unsigned long offset, size_t size,
 291                 enum dma_data_direction dir)
 292 {
 293         return dma_sync_single_for_cpu(dev, addr + offset, size, dir);
 294 }
 295
 296 static inline void dma_sync_single_range_for_device(struct device *dev,
 297                 dma_addr_t addr, unsigned long offset, size_t size,
 298                 enum dma_data_direction dir)
 299 {
 300         return dma_sync_single_for_device(dev, addr + offset, size, dir);
 301 }
 302
 303 /**
 304  * dma_map_sgtable - Map the given buffer for DMA
 305  * @dev:        The device for which to perform the DMA operation
 306  * @sgt:        The sg_table object describing the buffer
 307  * @dir:        DMA direction
 308  * @attrs:      Optional DMA attributes for the map operation
 309  *
 310  * Maps a buffer described by a scatterlist stored in the given sg_table
 311  * object for the @dir DMA operation by the @dev device. After success the
 312  * ownership for the buffer is transferred to the DMA domain.  One has to
 313  * call dma_sync_sgtable_for_cpu() or dma_unmap_sgtable() to move the
 314  * ownership of the buffer back to the CPU domain before touching the
 315  * buffer by the CPU.
 316  *
 317  * Returns 0 on success or -EINVAL on error during mapping the buffer.
 318  */
 319 static inline int dma_map_sgtable(struct device *dev, struct sg_table *sgt,
 320                 enum dma_data_direction dir, unsigned long attrs)
 321 {
 322         int nents;
 323
 324         nents = dma_map_sg_attrs(dev, sgt->sgl, sgt->orig_nents, dir, attrs);
 325         if (nents <= 0)
 326                 return -EINVAL;
 327         sgt->nents = nents;
 328         return 0;
 329 }
 330
 331 /**
 332  * dma_unmap_sgtable - Unmap the given buffer for DMA
 333  * @dev:        The device for which to perform the DMA operation
 334  * @sgt:        The sg_table object describing the buffer
 335  * @dir:        DMA direction
 336  * @attrs:      Optional DMA attributes for the unmap operation
 337  *
 338  * Unmaps a buffer described by a scatterlist stored in the given sg_table
 339  * object for the @dir DMA operation by the @dev device. After this function
 340  * the ownership of the buffer is transferred back to the CPU domain.
 341  */
 342 static inline void dma_unmap_sgtable(struct device *dev, struct sg_table *sgt,
 343                 enum dma_data_direction dir, unsigned long attrs)
 344 {
 345         dma_unmap_sg_attrs(dev, sgt->sgl, sgt->orig_nents, dir, attrs);
 346 }
 347
 348 /**
 349  * dma_sync_sgtable_for_cpu - Synchronize the given buffer for CPU access
 350  * @dev:        The device for which to perform the DMA operation
 351  * @sgt:        The sg_table object describing the buffer
 352  * @dir:        DMA direction
 353  *
 354  * Performs the needed cache synchronization and moves the ownership of the
 355  * buffer back to the CPU domain, so it is safe to perform any access to it
 356  * by the CPU. Before doing any further DMA operations, one has to transfer
 357  * the ownership of the buffer back to the DMA domain by calling the
 358  * dma_sync_sgtable_for_device().
 359  */
 360 static inline void dma_sync_sgtable_for_cpu(struct device *dev,
 361                 struct sg_table *sgt, enum dma_data_direction dir)
 362 {
 363         dma_sync_sg_for_cpu(dev, sgt->sgl, sgt->orig_nents, dir);
 364 }
 365
 366 /**
 367  * dma_sync_sgtable_for_device - Synchronize the given buffer for DMA
 368  * @dev:        The device for which to perform the DMA operation
 369  * @sgt:        The sg_table object describing the buffer
 370  * @dir:        DMA direction
 371  *
 372  * Performs the needed cache synchronization and moves the ownership of the
 373  * buffer back to the DMA domain, so it is safe to perform the DMA operation.
 374  * Once finished, one has to call dma_sync_sgtable_for_cpu() or
 375  * dma_unmap_sgtable().
 376  */
 377 static inline void dma_sync_sgtable_for_device(struct device *dev,
 378                 struct sg_table *sgt, enum dma_data_direction dir)
 379 {
 380         dma_sync_sg_for_device(dev, sgt->sgl, sgt->orig_nents, dir);
 381 }
 382
 383 #define dma_map_single(d, a, s, r) dma_map_single_attrs(d, a, s, r, 0)
 384 #define dma_unmap_single(d, a, s, r) dma_unmap_single_attrs(d, a, s, r, 0)
 385 #define dma_map_sg(d, s, n, r) dma_map_sg_attrs(d, s, n, r, 0)
 386 #define dma_unmap_sg(d, s, n, r) dma_unmap_sg_attrs(d, s, n, r, 0)
 387 #define dma_map_page(d, p, o, s, r) dma_map_page_attrs(d, p, o, s, r, 0)
 388 #define dma_unmap_page(d, a, s, r) dma_unmap_page_attrs(d, a, s, r, 0)
 389 #define dma_get_sgtable(d, t, v, h, s) dma_get_sgtable_attrs(d, t, v, h, s, 0)
 390 #define dma_mmap_coherent(d, v, c, h, s) dma_mmap_attrs(d, v, c, h, s, 0)
 391
 392 static inline void *dma_alloc_coherent(struct device *dev, size_t size,
 393                 dma_addr_t *dma_handle, gfp_t gfp)
 394 {
 395
 396         return dma_alloc_attrs(dev, size, dma_handle, gfp,
 397                         (gfp & __GFP_NOWARN) ? DMA_ATTR_NO_WARN : 0);
 398 }
 399
 400 static inline void dma_free_coherent(struct device *dev, size_t size,
 401                 void *cpu_addr, dma_addr_t dma_handle)
 402 {
 403         return dma_free_attrs(dev, size, cpu_addr, dma_handle, 0);
 404 }
 405
 406
 407 static inline u64 dma_get_mask(struct device *dev)
 408 {
 409         if (dev->dma_mask && *dev->dma_mask)
 410                 return *dev->dma_mask;
 411         return DMA_BIT_MASK(32);
 412 }
 413
 414 /*
 415  * Set both the DMA mask and the coherent DMA mask to the same thing.
 416  * Note that we don't check the return value from dma_set_coherent_mask()
 417  * as the DMA API guarantees that the coherent DMA mask can be set to
 418  * the same or smaller than the streaming DMA mask.
 419  */
 420 static inline int dma_set_mask_and_coherent(struct device *dev, u64 mask)
 421 {
 422         int rc = dma_set_mask(dev, mask);
 423         if (rc == 0)
 424                 dma_set_coherent_mask(dev, mask);
 425         return rc;
 426 }
 427
 428 /*
 429  * Similar to the above, except it deals with the case where the device
 430  * does not have dev->dma_mask appropriately setup.
 431  */
 432 static inline int dma_coerce_mask_and_coherent(struct device *dev, u64 mask)
 433 {
 434         dev->dma_mask = &dev->coherent_dma_mask;
 435         return dma_set_mask_and_coherent(dev, mask);
 436 }
 437
 438 /**
 439  * dma_addressing_limited - return if the device is addressing limited
 440  * @dev:        device to check
 441  *
 442  * Return %true if the devices DMA mask is too small to address all memory in
 443  * the system, else %false.  Lack of addressing bits is the prime reason for
 444  * bounce buffering, but might not be the only one.
 445  */
 446 static inline bool dma_addressing_limited(struct device *dev)
 447 {
 448         return min_not_zero(dma_get_mask(dev), dev->bus_dma_limit) <
 449                             dma_get_required_mask(dev);
 450 }
 451
 452 static inline unsigned int dma_get_max_seg_size(struct device *dev)
 453 {
 454         if (dev->dma_parms && dev->dma_parms->max_segment_size)
 455                 return dev->dma_parms->max_segment_size;
 456         return SZ_64K;
 457 }
 458
 459 static inline int dma_set_max_seg_size(struct device *dev, unsigned int size)
 460 {
 461         if (dev->dma_parms) {
 462                 dev->dma_parms->max_segment_size = size;
 463                 return 0;
 464         }
 465         return -EIO;
 466 }
 467
 468 static inline unsigned long dma_get_seg_boundary(struct device *dev)
 469 {
 470         if (dev->dma_parms && dev->dma_parms->segment_boundary_mask)
 471                 return dev->dma_parms->segment_boundary_mask;
 472         return ULONG_MAX;
 473 }
 474
 475 /**
 476  * dma_get_seg_boundary_nr_pages - return the segment boundary in "page" units
 477  * @dev: device to guery the boundary for
 478  * @page_shift: ilog() of the IOMMU page size
 479  *
 480  * Return the segment boundary in IOMMU page units (which may be different from
 481  * the CPU page size) for the passed in device.
 482  *
 483  * If @dev is NULL a boundary of U32_MAX is assumed, this case is just for
 484  * non-DMA API callers.
 485  */
 486 static inline unsigned long dma_get_seg_boundary_nr_pages(struct device *dev,
 487                 unsigned int page_shift)
 488 {
 489         if (!dev)
 490                 return (U32_MAX >> page_shift) + 1;
 491         return (dma_get_seg_boundary(dev) >> page_shift) + 1;
 492 }
 493
 494 static inline int dma_set_seg_boundary(struct device *dev, unsigned long mask)
 495 {
 496         if (dev->dma_parms) {
 497                 dev->dma_parms->segment_boundary_mask = mask;
 498                 return 0;
 499         }
 500         return -EIO;
 501 }
 502
 503 static inline int dma_get_cache_alignment(void)
 504 {
 505 #ifdef ARCH_DMA_MINALIGN
 506         return ARCH_DMA_MINALIGN;
 507 #endif
 508         return 1;
 509 }
 510
 511 static inline void *dmam_alloc_coherent(struct device *dev, size_t size,
 512                 dma_addr_t *dma_handle, gfp_t gfp)
 513 {
 514         return dmam_alloc_attrs(dev, size, dma_handle, gfp,
 515                         (gfp & __GFP_NOWARN) ? DMA_ATTR_NO_WARN : 0);
 516 }
 517
 518 static inline void *dma_alloc_wc(struct device *dev, size_t size,
 519                                  dma_addr_t *dma_addr, gfp_t gfp)
 520 {
 521         unsigned long attrs = DMA_ATTR_WRITE_COMBINE;
 522
 523         if (gfp & __GFP_NOWARN)
 524                 attrs |= DMA_ATTR_NO_WARN;
 525
 526         return dma_alloc_attrs(dev, size, dma_addr, gfp, attrs);
 527 }
 528
 529 static inline void dma_free_wc(struct device *dev, size_t size,
 530                                void *cpu_addr, dma_addr_t dma_addr)
 531 {
 532         return dma_free_attrs(dev, size, cpu_addr, dma_addr,
 533                               DMA_ATTR_WRITE_COMBINE);
 534 }
 535
 536 static inline int dma_mmap_wc(struct device *dev,
 537                               struct vm_area_struct *vma,
 538                               void *cpu_addr, dma_addr_t dma_addr,
 539                               size_t size)
 540 {
 541         return dma_mmap_attrs(dev, vma, cpu_addr, dma_addr, size,
 542                               DMA_ATTR_WRITE_COMBINE);
 543 }
 544
 545 #ifdef CONFIG_NEED_DMA_MAP_STATE
 546 #define DEFINE_DMA_UNMAP_ADDR(ADDR_NAME)        dma_addr_t ADDR_NAME
 547 #define DEFINE_DMA_UNMAP_LEN(LEN_NAME)          __u32 LEN_NAME
 548 #define dma_unmap_addr(PTR, ADDR_NAME)           ((PTR)->ADDR_NAME)
 549 #define dma_unmap_addr_set(PTR, ADDR_NAME, VAL)  (((PTR)->ADDR_NAME) = (VAL))
 550 #define dma_unmap_len(PTR, LEN_NAME)             ((PTR)->LEN_NAME)
 551 #define dma_unmap_len_set(PTR, LEN_NAME, VAL)    (((PTR)->LEN_NAME) = (VAL))
 552 #else
 553 #define DEFINE_DMA_UNMAP_ADDR(ADDR_NAME)
 554 #define DEFINE_DMA_UNMAP_LEN(LEN_NAME)
 555 #define dma_unmap_addr(PTR, ADDR_NAME)           (0)
 556 #define dma_unmap_addr_set(PTR, ADDR_NAME, VAL)  do { } while (0)
 557 #define dma_unmap_len(PTR, LEN_NAME)             (0)
 558 #define dma_unmap_len_set(PTR, LEN_NAME, VAL)    do { } while (0)
 559 #endif
 560
 561 #endif /* _LINUX_DMA_MAPPING_H */