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 bool dma_pci_p2pdma_supported(struct device *dev);
 144 int dma_set_mask(struct device *dev, u64 mask);
 145 int dma_set_coherent_mask(struct device *dev, u64 mask);
 146 u64 dma_get_required_mask(struct device *dev);
 147 size_t dma_max_mapping_size(struct device *dev);
 148 size_t dma_opt_mapping_size(struct device *dev);
 149 bool dma_need_sync(struct device *dev, dma_addr_t dma_addr);
 150 unsigned long dma_get_merge_boundary(struct device *dev);
 151 struct sg_table *dma_alloc_noncontiguous(struct device *dev, size_t size,
 152                 enum dma_data_direction dir, gfp_t gfp, unsigned long attrs);
 153 void dma_free_noncontiguous(struct device *dev, size_t size,
 154                 struct sg_table *sgt, enum dma_data_direction dir);
 155 void *dma_vmap_noncontiguous(struct device *dev, size_t size,
 156                 struct sg_table *sgt);
 157 void dma_vunmap_noncontiguous(struct device *dev, void *vaddr);
 158 int dma_mmap_noncontiguous(struct device *dev, struct vm_area_struct *vma,
 159                 size_t size, struct sg_table *sgt);
 160 #else /* CONFIG_HAS_DMA */
 161 static inline dma_addr_t dma_map_page_attrs(struct device *dev,
 162                 struct page *page, size_t offset, size_t size,
 163                 enum dma_data_direction dir, unsigned long attrs)
 164 {
 165         return DMA_MAPPING_ERROR;
 166 }
 167 static inline void dma_unmap_page_attrs(struct device *dev, dma_addr_t addr,
 168                 size_t size, enum dma_data_direction dir, unsigned long attrs)
 169 {
 170 }
 171 static inline unsigned int dma_map_sg_attrs(struct device *dev,
 172                 struct scatterlist *sg, int nents, enum dma_data_direction dir,
 173                 unsigned long attrs)
 174 {
 175         return 0;
 176 }
 177 static inline void dma_unmap_sg_attrs(struct device *dev,
 178                 struct scatterlist *sg, int nents, enum dma_data_direction dir,
 179                 unsigned long attrs)
 180 {
 181 }
 182 static inline int dma_map_sgtable(struct device *dev, struct sg_table *sgt,
 183                 enum dma_data_direction dir, unsigned long attrs)
 184 {
 185         return -EOPNOTSUPP;
 186 }
 187 static inline dma_addr_t dma_map_resource(struct device *dev,
 188                 phys_addr_t phys_addr, size_t size, enum dma_data_direction dir,
 189                 unsigned long attrs)
 190 {
 191         return DMA_MAPPING_ERROR;
 192 }
 193 static inline void dma_unmap_resource(struct device *dev, dma_addr_t addr,
 194                 size_t size, enum dma_data_direction dir, unsigned long attrs)
 195 {
 196 }
 197 static inline void dma_sync_single_for_cpu(struct device *dev, dma_addr_t addr,
 198                 size_t size, enum dma_data_direction dir)
 199 {
 200 }
 201 static inline void dma_sync_single_for_device(struct device *dev,
 202                 dma_addr_t addr, size_t size, enum dma_data_direction dir)
 203 {
 204 }
 205 static inline void dma_sync_sg_for_cpu(struct device *dev,
 206                 struct scatterlist *sg, int nelems, enum dma_data_direction dir)
 207 {
 208 }
 209 static inline void dma_sync_sg_for_device(struct device *dev,
 210                 struct scatterlist *sg, int nelems, enum dma_data_direction dir)
 211 {
 212 }
 213 static inline int dma_mapping_error(struct device *dev, dma_addr_t dma_addr)
 214 {
 215         return -ENOMEM;
 216 }
 217 static inline void *dma_alloc_attrs(struct device *dev, size_t size,
 218                 dma_addr_t *dma_handle, gfp_t flag, unsigned long attrs)
 219 {
 220         return NULL;
 221 }
 222 static void dma_free_attrs(struct device *dev, size_t size, void *cpu_addr,
 223                 dma_addr_t dma_handle, unsigned long attrs)
 224 {
 225 }
 226 static inline void *dmam_alloc_attrs(struct device *dev, size_t size,
 227                 dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs)
 228 {
 229         return NULL;
 230 }
 231 static inline void dmam_free_coherent(struct device *dev, size_t size,
 232                 void *vaddr, dma_addr_t dma_handle)
 233 {
 234 }
 235 static inline int dma_get_sgtable_attrs(struct device *dev,
 236                 struct sg_table *sgt, void *cpu_addr, dma_addr_t dma_addr,
 237                 size_t size, unsigned long attrs)
 238 {
 239         return -ENXIO;
 240 }
 241 static inline int dma_mmap_attrs(struct device *dev, struct vm_area_struct *vma,
 242                 void *cpu_addr, dma_addr_t dma_addr, size_t size,
 243                 unsigned long attrs)
 244 {
 245         return -ENXIO;
 246 }
 247 static inline bool dma_can_mmap(struct device *dev)
 248 {
 249         return false;
 250 }
 251 static inline int dma_supported(struct device *dev, u64 mask)
 252 {
 253         return 0;
 254 }
 255 static inline bool dma_pci_p2pdma_supported(struct device *dev)
 256 {
 257         return false;
 258 }
 259 static inline int dma_set_mask(struct device *dev, u64 mask)
 260 {
 261         return -EIO;
 262 }
 263 static inline int dma_set_coherent_mask(struct device *dev, u64 mask)
 264 {
 265         return -EIO;
 266 }
 267 static inline u64 dma_get_required_mask(struct device *dev)
 268 {
 269         return 0;
 270 }
 271 static inline size_t dma_max_mapping_size(struct device *dev)
 272 {
 273         return 0;
 274 }
 275 static inline size_t dma_opt_mapping_size(struct device *dev)
 276 {
 277         return 0;
 278 }
 279 static inline bool dma_need_sync(struct device *dev, dma_addr_t dma_addr)
 280 {
 281         return false;
 282 }
 283 static inline unsigned long dma_get_merge_boundary(struct device *dev)
 284 {
 285         return 0;
 286 }
 287 static inline struct sg_table *dma_alloc_noncontiguous(struct device *dev,
 288                 size_t size, enum dma_data_direction dir, gfp_t gfp,
 289                 unsigned long attrs)
 290 {
 291         return NULL;
 292 }
 293 static inline void dma_free_noncontiguous(struct device *dev, size_t size,
 294                 struct sg_table *sgt, enum dma_data_direction dir)
 295 {
 296 }
 297 static inline void *dma_vmap_noncontiguous(struct device *dev, size_t size,
 298                 struct sg_table *sgt)
 299 {
 300         return NULL;
 301 }
 302 static inline void dma_vunmap_noncontiguous(struct device *dev, void *vaddr)
 303 {
 304 }
 305 static inline int dma_mmap_noncontiguous(struct device *dev,
 306                 struct vm_area_struct *vma, size_t size, struct sg_table *sgt)
 307 {
 308         return -EINVAL;
 309 }
 310 #endif /* CONFIG_HAS_DMA */
 311
 312 struct page *dma_alloc_pages(struct device *dev, size_t size,
 313                 dma_addr_t *dma_handle, enum dma_data_direction dir, gfp_t gfp);
 314 void dma_free_pages(struct device *dev, size_t size, struct page *page,
 315                 dma_addr_t dma_handle, enum dma_data_direction dir);
 316 int dma_mmap_pages(struct device *dev, struct vm_area_struct *vma,
 317                 size_t size, struct page *page);
 318
 319 static inline void *dma_alloc_noncoherent(struct device *dev, size_t size,
 320                 dma_addr_t *dma_handle, enum dma_data_direction dir, gfp_t gfp)
 321 {
 322         struct page *page = dma_alloc_pages(dev, size, dma_handle, dir, gfp);
 323         return page ? page_address(page) : NULL;
 324 }
 325
 326 static inline void dma_free_noncoherent(struct device *dev, size_t size,
 327                 void *vaddr, dma_addr_t dma_handle, enum dma_data_direction dir)
 328 {
 329         dma_free_pages(dev, size, virt_to_page(vaddr), dma_handle, dir);
 330 }
 331
 332 static inline dma_addr_t dma_map_single_attrs(struct device *dev, void *ptr,
 333                 size_t size, enum dma_data_direction dir, unsigned long attrs)
 334 {
 335         /* DMA must never operate on areas that might be remapped. */
 336         if (dev_WARN_ONCE(dev, is_vmalloc_addr(ptr),
 337                           "rejecting DMA map of vmalloc memory\n"))
 338                 return DMA_MAPPING_ERROR;
 339         debug_dma_map_single(dev, ptr, size);
 340         return dma_map_page_attrs(dev, virt_to_page(ptr), offset_in_page(ptr),
 341                         size, dir, attrs);
 342 }
 343
 344 static inline void dma_unmap_single_attrs(struct device *dev, dma_addr_t addr,
 345                 size_t size, enum dma_data_direction dir, unsigned long attrs)
 346 {
 347         return dma_unmap_page_attrs(dev, addr, size, dir, attrs);
 348 }
 349
 350 static inline void dma_sync_single_range_for_cpu(struct device *dev,
 351                 dma_addr_t addr, unsigned long offset, size_t size,
 352                 enum dma_data_direction dir)
 353 {
 354         return dma_sync_single_for_cpu(dev, addr + offset, size, dir);
 355 }
 356
 357 static inline void dma_sync_single_range_for_device(struct device *dev,
 358                 dma_addr_t addr, unsigned long offset, size_t size,
 359                 enum dma_data_direction dir)
 360 {
 361         return dma_sync_single_for_device(dev, addr + offset, size, dir);
 362 }
 363
 364 /**
 365  * dma_unmap_sgtable - Unmap the given buffer for DMA
 366  * @dev:        The device for which to perform the DMA operation
 367  * @sgt:        The sg_table object describing the buffer
 368  * @dir:        DMA direction
 369  * @attrs:      Optional DMA attributes for the unmap operation
 370  *
 371  * Unmaps a buffer described by a scatterlist stored in the given sg_table
 372  * object for the @dir DMA operation by the @dev device. After this function
 373  * the ownership of the buffer is transferred back to the CPU domain.
 374  */
 375 static inline void dma_unmap_sgtable(struct device *dev, struct sg_table *sgt,
 376                 enum dma_data_direction dir, unsigned long attrs)
 377 {
 378         dma_unmap_sg_attrs(dev, sgt->sgl, sgt->orig_nents, dir, attrs);
 379 }
 380
 381 /**
 382  * dma_sync_sgtable_for_cpu - Synchronize the given buffer for CPU access
 383  * @dev:        The device for which to perform the DMA operation
 384  * @sgt:        The sg_table object describing the buffer
 385  * @dir:        DMA direction
 386  *
 387  * Performs the needed cache synchronization and moves the ownership of the
 388  * buffer back to the CPU domain, so it is safe to perform any access to it
 389  * by the CPU. Before doing any further DMA operations, one has to transfer
 390  * the ownership of the buffer back to the DMA domain by calling the
 391  * dma_sync_sgtable_for_device().
 392  */
 393 static inline void dma_sync_sgtable_for_cpu(struct device *dev,
 394                 struct sg_table *sgt, enum dma_data_direction dir)
 395 {
 396         dma_sync_sg_for_cpu(dev, sgt->sgl, sgt->orig_nents, dir);
 397 }
 398
 399 /**
 400  * dma_sync_sgtable_for_device - Synchronize the given buffer for DMA
 401  * @dev:        The device for which to perform the DMA operation
 402  * @sgt:        The sg_table object describing the buffer
 403  * @dir:        DMA direction
 404  *
 405  * Performs the needed cache synchronization and moves the ownership of the
 406  * buffer back to the DMA domain, so it is safe to perform the DMA operation.
 407  * Once finished, one has to call dma_sync_sgtable_for_cpu() or
 408  * dma_unmap_sgtable().
 409  */
 410 static inline void dma_sync_sgtable_for_device(struct device *dev,
 411                 struct sg_table *sgt, enum dma_data_direction dir)
 412 {
 413         dma_sync_sg_for_device(dev, sgt->sgl, sgt->orig_nents, dir);
 414 }
 415
 416 #define dma_map_single(d, a, s, r) dma_map_single_attrs(d, a, s, r, 0)
 417 #define dma_unmap_single(d, a, s, r) dma_unmap_single_attrs(d, a, s, r, 0)
 418 #define dma_map_sg(d, s, n, r) dma_map_sg_attrs(d, s, n, r, 0)
 419 #define dma_unmap_sg(d, s, n, r) dma_unmap_sg_attrs(d, s, n, r, 0)
 420 #define dma_map_page(d, p, o, s, r) dma_map_page_attrs(d, p, o, s, r, 0)
 421 #define dma_unmap_page(d, a, s, r) dma_unmap_page_attrs(d, a, s, r, 0)
 422 #define dma_get_sgtable(d, t, v, h, s) dma_get_sgtable_attrs(d, t, v, h, s, 0)
 423 #define dma_mmap_coherent(d, v, c, h, s) dma_mmap_attrs(d, v, c, h, s, 0)
 424
 425 static inline void *dma_alloc_coherent(struct device *dev, size_t size,
 426                 dma_addr_t *dma_handle, gfp_t gfp)
 427 {
 428         return dma_alloc_attrs(dev, size, dma_handle, gfp,
 429                         (gfp & __GFP_NOWARN) ? DMA_ATTR_NO_WARN : 0);
 430 }
 431
 432 static inline void dma_free_coherent(struct device *dev, size_t size,
 433                 void *cpu_addr, dma_addr_t dma_handle)
 434 {
 435         return dma_free_attrs(dev, size, cpu_addr, dma_handle, 0);
 436 }
 437
 438
 439 static inline u64 dma_get_mask(struct device *dev)
 440 {
 441         if (dev->dma_mask && *dev->dma_mask)
 442                 return *dev->dma_mask;
 443         return DMA_BIT_MASK(32);
 444 }
 445
 446 /*
 447  * Set both the DMA mask and the coherent DMA mask to the same thing.
 448  * Note that we don't check the return value from dma_set_coherent_mask()
 449  * as the DMA API guarantees that the coherent DMA mask can be set to
 450  * the same or smaller than the streaming DMA mask.
 451  */
 452 static inline int dma_set_mask_and_coherent(struct device *dev, u64 mask)
 453 {
 454         int rc = dma_set_mask(dev, mask);
 455         if (rc == 0)
 456                 dma_set_coherent_mask(dev, mask);
 457         return rc;
 458 }
 459
 460 /*
 461  * Similar to the above, except it deals with the case where the device
 462  * does not have dev->dma_mask appropriately setup.
 463  */
 464 static inline int dma_coerce_mask_and_coherent(struct device *dev, u64 mask)
 465 {
 466         dev->dma_mask = &dev->coherent_dma_mask;
 467         return dma_set_mask_and_coherent(dev, mask);
 468 }
 469
 470 /**
 471  * dma_addressing_limited - return if the device is addressing limited
 472  * @dev:        device to check
 473  *
 474  * Return %true if the devices DMA mask is too small to address all memory in
 475  * the system, else %false.  Lack of addressing bits is the prime reason for
 476  * bounce buffering, but might not be the only one.
 477  */
 478 static inline bool dma_addressing_limited(struct device *dev)
 479 {
 480         return min_not_zero(dma_get_mask(dev), dev->bus_dma_limit) <
 481                             dma_get_required_mask(dev);
 482 }
 483
 484 static inline unsigned int dma_get_max_seg_size(struct device *dev)
 485 {
 486         if (dev->dma_parms && dev->dma_parms->max_segment_size)
 487                 return dev->dma_parms->max_segment_size;
 488         return SZ_64K;
 489 }
 490
 491 static inline int dma_set_max_seg_size(struct device *dev, unsigned int size)
 492 {
 493         if (dev->dma_parms) {
 494                 dev->dma_parms->max_segment_size = size;
 495                 return 0;
 496         }
 497         return -EIO;
 498 }
 499
 500 static inline unsigned long dma_get_seg_boundary(struct device *dev)
 501 {
 502         if (dev->dma_parms && dev->dma_parms->segment_boundary_mask)
 503                 return dev->dma_parms->segment_boundary_mask;
 504         return ULONG_MAX;
 505 }
 506
 507 /**
 508  * dma_get_seg_boundary_nr_pages - return the segment boundary in "page" units
 509  * @dev: device to guery the boundary for
 510  * @page_shift: ilog() of the IOMMU page size
 511  *
 512  * Return the segment boundary in IOMMU page units (which may be different from
 513  * the CPU page size) for the passed in device.
 514  *
 515  * If @dev is NULL a boundary of U32_MAX is assumed, this case is just for
 516  * non-DMA API callers.
 517  */
 518 static inline unsigned long dma_get_seg_boundary_nr_pages(struct device *dev,
 519                 unsigned int page_shift)
 520 {
 521         if (!dev)
 522                 return (U32_MAX >> page_shift) + 1;
 523         return (dma_get_seg_boundary(dev) >> page_shift) + 1;
 524 }
 525
 526 static inline int dma_set_seg_boundary(struct device *dev, unsigned long mask)
 527 {
 528         if (dev->dma_parms) {
 529                 dev->dma_parms->segment_boundary_mask = mask;
 530                 return 0;
 531         }
 532         return -EIO;
 533 }
 534
 535 static inline unsigned int dma_get_min_align_mask(struct device *dev)
 536 {
 537         if (dev->dma_parms)
 538                 return dev->dma_parms->min_align_mask;
 539         return 0;
 540 }
 541
 542 static inline int dma_set_min_align_mask(struct device *dev,
 543                 unsigned int min_align_mask)
 544 {
 545         if (WARN_ON_ONCE(!dev->dma_parms))
 546                 return -EIO;
 547         dev->dma_parms->min_align_mask = min_align_mask;
 548         return 0;
 549 }
 550
 551 static inline int dma_get_cache_alignment(void)
 552 {
 553 #ifdef ARCH_DMA_MINALIGN
 554         return ARCH_DMA_MINALIGN;
 555 #endif
 556         return 1;
 557 }
 558
 559 static inline void *dmam_alloc_coherent(struct device *dev, size_t size,
 560                 dma_addr_t *dma_handle, gfp_t gfp)
 561 {
 562         return dmam_alloc_attrs(dev, size, dma_handle, gfp,
 563                         (gfp & __GFP_NOWARN) ? DMA_ATTR_NO_WARN : 0);
 564 }
 565
 566 static inline void *dma_alloc_wc(struct device *dev, size_t size,
 567                                  dma_addr_t *dma_addr, gfp_t gfp)
 568 {
 569         unsigned long attrs = DMA_ATTR_WRITE_COMBINE;
 570
 571         if (gfp & __GFP_NOWARN)
 572                 attrs |= DMA_ATTR_NO_WARN;
 573
 574         return dma_alloc_attrs(dev, size, dma_addr, gfp, attrs);
 575 }
 576
 577 static inline void dma_free_wc(struct device *dev, size_t size,
 578                                void *cpu_addr, dma_addr_t dma_addr)
 579 {
 580         return dma_free_attrs(dev, size, cpu_addr, dma_addr,
 581                               DMA_ATTR_WRITE_COMBINE);
 582 }
 583
 584 static inline int dma_mmap_wc(struct device *dev,
 585                               struct vm_area_struct *vma,
 586                               void *cpu_addr, dma_addr_t dma_addr,
 587                               size_t size)
 588 {
 589         return dma_mmap_attrs(dev, vma, cpu_addr, dma_addr, size,
 590                               DMA_ATTR_WRITE_COMBINE);
 591 }
 592
 593 #ifdef CONFIG_NEED_DMA_MAP_STATE
 594 #define DEFINE_DMA_UNMAP_ADDR(ADDR_NAME)        dma_addr_t ADDR_NAME
 595 #define DEFINE_DMA_UNMAP_LEN(LEN_NAME)          __u32 LEN_NAME
 596 #define dma_unmap_addr(PTR, ADDR_NAME)           ((PTR)->ADDR_NAME)
 597 #define dma_unmap_addr_set(PTR, ADDR_NAME, VAL)  (((PTR)->ADDR_NAME) = (VAL))
 598 #define dma_unmap_len(PTR, LEN_NAME)             ((PTR)->LEN_NAME)
 599 #define dma_unmap_len_set(PTR, LEN_NAME, VAL)    (((PTR)->LEN_NAME) = (VAL))
 600 #else
 601 #define DEFINE_DMA_UNMAP_ADDR(ADDR_NAME)
 602 #define DEFINE_DMA_UNMAP_LEN(LEN_NAME)
 603 #define dma_unmap_addr(PTR, ADDR_NAME)           (0)
 604 #define dma_unmap_addr_set(PTR, ADDR_NAME, VAL)  do { } while (0)
 605 #define dma_unmap_len(PTR, LEN_NAME)             (0)
 606 #define dma_unmap_len_set(PTR, LEN_NAME, VAL)    do { } while (0)
 607 #endif
 608
 609 #endif /* _LINUX_DMA_MAPPING_H */