LXR linux/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
  10static 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
  20static 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
  29extern 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
  35static 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
  45