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 (unlikely(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 unsigned int dma_map_sg_attrs(struct device *dev, struct scatterlist *sg,
 109                 int nents, 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 int dma_map_sgtable(struct device *dev, struct sg_table *sgt,
 114                 enum dma_data_direction dir, unsigned long attrs);
 115 dma_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);
 117 void dma_unmap_resource(struct device *dev, dma_addr_t addr, size_t size,
 118                 enum dma_data_direction dir, unsigned long attrs);
 119 void dma_sync_single_for_cpu(struct device *dev, dma_addr_t addr, size_t size,
 120                 enum dma_data_direction dir);
 121 void dma_sync_single_for_device(struct device *dev, dma_addr_t addr,
 122                 size_t size, enum dma_data_direction dir);
 123 void dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg,
 124                     int nelems, enum dma_data_direction dir);
 125 void dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg,
 126                        int nelems, enum dma_data_direction dir);
 127 void *dma_alloc_attrs(struct device *dev, size_t size, dma_addr_t *dma_handle,
 128                 gfp_t flag, unsigned long attrs);
 129 void dma_free_attrs(struct device *dev, size_t size, void *cpu_addr,
 130                 dma_addr_t dma_handle, unsigned long attrs);
 131 void *dmam_alloc_attrs(struct device *dev, size_t size, dma_addr_t *dma_handle,
 132                 gfp_t gfp, unsigned long attrs);
 133 void dmam_free_coherent(struct device *dev, size_t size, void *vaddr,
 134                 dma_addr_t dma_handle);
 135 int 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);
 138 int 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);
 141 bool dma_can_mmap(struct device *dev);
 142 int dma_supported(struct device *dev, u64 mask);
 143 int dma_set_mask(struct device *dev, u64 mask);
 144 int dma_set_coherent_mask(struct device *dev, u64 mask);
 145 u64 dma_get_required_mask(struct device *dev);
 146 size_t dma_max_mapping_size(struct device *dev);
 147 bool dma_need_sync(struct device *dev, dma_addr_t dma_addr);
 148 unsigned long dma_get_merge_boundary(struct device *dev);
 149 struct sg_table *dma_alloc_noncontiguous(struct device *dev, size_t size,
 150                 enum dma_data_direction dir, gfp_t gfp, unsigned long attrs);
 151 void dma_free_noncontiguous(struct device *dev, size_t size,
 152                 struct sg_table *sgt, enum dma_data_direction dir);
 153 void *dma_vmap_noncontiguous(struct device *dev, size_t size,
 154                 struct sg_table *sgt);
 155 void dma_vunmap_noncontiguous(struct device *dev, void *vaddr);
 156 int dma_mmap_noncontiguous(struct device *dev, struct vm_area_struct *vma,
 157                 size_t size, struct sg_table *sgt);
 158 #else /* CONFIG_HAS_DMA */
 159 static 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 }
 165 static 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 }
 169 static 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 }
 175 static 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 }
 180 static 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 }
 185 static 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 }
 191 static 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 }
 195 static 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 }
 199 static 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 }
 203 static inline void dma_sync_sg_for_cpu(struct device *dev,
 204                 struct scatterlist *sg, int nelems, enum dma_data_direction dir)
 205 {
 206 }
 207 static inline void dma_sync_sg_for_device(struct device *dev,
 208                 struct scatterlist *sg, int nelems, enum dma_data_direction dir)
 209 {
 210 }
 211 static inline int dma_mapping_error(struct device *dev, dma_addr_t dma_addr)
 212 {
 213         return -ENOMEM;
 214 }
 215 static 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 }
 220 static void dma_free_attrs(struct device *dev, size_t size, void *cpu_addr,
 221                 dma_addr_t dma_handle, unsigned long attrs)
 222 {
 223 }
 224 static 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 }
 229 static inline void dmam_free_coherent(struct device *dev, size_t size,
 230                 void *vaddr, dma_addr_t dma_handle)
 231 {
 232 }
 233 static 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 }
 239 static 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 }
 245 static inline bool dma_can_mmap(struct device *dev)
 246 {
 247         return false;
 248 }
 249 static inline int dma_supported(struct device *dev, u64 mask)
 250 {
 251         return 0;
 252 }
 253 static inline int dma_set_mask(struct device *dev, u64 mask)
 254 {
 255         return -EIO;
 256 }
 257 static inline int dma_set_coherent_mask(struct device *dev, u64 mask)
 258 {
 259         return -EIO;
 260 }
 261 static inline u64 dma_get_required_mask(struct device *dev)
 262 {
 263         return 0;
 264 }
 265 static inline size_t dma_max_mapping_size(struct device *dev)
 266 {
 267         return 0;
 268 }
 269 static inline bool dma_need_sync(struct device *dev, dma_addr_t dma_addr)
 270 {
 271         return false;
 272 }
 273 static inline unsigned long dma_get_merge_boundary(struct device *dev)
 274 {
 275         return 0;
 276 }
 277 static 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 }
 283 static inline void dma_free_noncontiguous(struct device *dev, size_t size,
 284                 struct sg_table *sgt, enum dma_data_direction dir)
 285 {
 286 }
 287 static inline void *dma_vmap_noncontiguous(struct device *dev, size_t size,
 288                 struct sg_table *sgt)
 289 {
 290         return NULL;
 291 }
 292 static inline void dma_vunmap_noncontiguous(struct device *dev, void *vaddr)
 293 {
 294 }
 295 static 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
 302 struct page *dma_alloc_pages(struct device *dev, size_t size,
 303                 dma_addr_t *dma_handle, enum dma_data_direction dir, gfp_t gfp);
 304 void dma_free_pages(struct device *dev, size_t size, struct page *page,
 305                 dma_addr_t dma_handle, enum dma_data_direction dir);
 306 int dma_mmap_pages(struct device *dev, struct vm_area_struct *vma,
 307                 size_t size, struct page *page);
 308
 309 static 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
 316 static 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
 322 static 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
 334 static 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
 340 static 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
 347 static 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  */
 365 static 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  */
 383 static 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  */
 400 static 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
 415 static 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
 422 static 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
 429 static 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  */
 442 static 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  */
 454 static 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  */
 468 static 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
 474 static 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
 481 static 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
 490 static 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  */
 508 static 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
 516 static 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
 525 static 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
 532 static 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
 541 static 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
 549 static 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
 556 static 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
 567 static 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
 574 static 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 */