include/linux/iommu-helper.h

0001 /* SPDX-License-Identifier: GPL-2.0 */
0002 #ifndef _LINUX_IOMMU_HELPER_H
0003 #define _LINUX_IOMMU_HELPER_H
0004
0005 #include <linux/bug.h>
0006 #include <linux/log2.h>
0007 #include <linux/math.h>
0008 #include <linux/types.h>
0009
0010 static inline unsigned long iommu_device_max_index(unsigned long size,
0011                            unsigned long offset,
0012                            u64 dma_mask)
0013 {
0014     if (size + offset > dma_mask)
0015         return dma_mask - offset + 1;
0016     else
0017         return size;
0018 }
0019
0020 static inline int iommu_is_span_boundary(unsigned int index, unsigned int nr,
0021         unsigned long shift, unsigned long boundary_size)
0022 {
0023     BUG_ON(!is_power_of_2(boundary_size));
0024
0025     shift = (shift + index) & (boundary_size - 1);
0026     return shift + nr > boundary_size;
0027 }
0028
0029 extern unsigned long iommu_area_alloc(unsigned long *map, unsigned long size,
0030                       unsigned long start, unsigned int nr,
0031                       unsigned long shift,
0032                       unsigned long boundary_size,
0033                       unsigned long align_mask);
0034
0035 static inline unsigned long iommu_num_pages(unsigned long addr,
0036                         unsigned long len,
0037                         unsigned long io_page_size)
0038 {
0039     unsigned long size = (addr & (io_page_size - 1)) + len;
0040
0041     return DIV_ROUND_UP(size, io_page_size);
0042 }
0043
0044 #endif