include/linux/iommu-helper.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef _LINUX_IOMMU_HELPER_H
   3 #define _LINUX_IOMMU_HELPER_H
   4
   5 #include <linux/bug.h>
   6 #include <linux/log2.h>
   7 #include <linux/math.h>
   8 #include <linux/types.h>
   9
  10 static inline unsigned long iommu_device_max_index(unsigned long size,
  11                                                    unsigned long offset,
  12                                                    u64 dma_mask)
  13 {
  14         if (size + offset > dma_mask)
  15                 return dma_mask - offset + 1;
  16         else
  17                 return size;
  18 }
  19
  20 static inline int iommu_is_span_boundary(unsigned int index, unsigned int nr,
  21                 unsigned long shift, unsigned long boundary_size)
  22 {
  23         BUG_ON(!is_power_of_2(boundary_size));
  24
  25         shift = (shift + index) & (boundary_size - 1);
  26         return shift + nr > boundary_size;
  27 }
  28
  29 extern unsigned long iommu_area_alloc(unsigned long *map, unsigned long size,
  30                                       unsigned long start, unsigned int nr,
  31                                       unsigned long shift,
  32                                       unsigned long boundary_size,
  33                                       unsigned long align_mask);
  34
  35 static inline unsigned long iommu_num_pages(unsigned long addr,
  36                                             unsigned long len,
  37                                             unsigned long io_page_size)
  38 {
  39         unsigned long size = (addr & (io_page_size - 1)) + len;
  40
  41         return DIV_ROUND_UP(size, io_page_size);
  42 }
  43
  44 #endif