diff options
Diffstat (limited to 'include/linux/iommu-helper.h')
-rw-r--r-- | include/linux/iommu-helper.h | 42 |
1 files changed, 42 insertions, 0 deletions
diff --git a/include/linux/iommu-helper.h b/include/linux/iommu-helper.h new file mode 100644 index 000000000..70d01edcb --- /dev/null +++ b/include/linux/iommu-helper.h @@ -0,0 +1,42 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _LINUX_IOMMU_HELPER_H +#define _LINUX_IOMMU_HELPER_H + +#include <linux/bug.h> +#include <linux/kernel.h> + +static inline unsigned long iommu_device_max_index(unsigned long size, + unsigned long offset, + u64 dma_mask) +{ + if (size + offset > dma_mask) + return dma_mask - offset + 1; + else + return size; +} + +static inline int iommu_is_span_boundary(unsigned int index, unsigned int nr, + unsigned long shift, unsigned long boundary_size) +{ + BUG_ON(!is_power_of_2(boundary_size)); + + shift = (shift + index) & (boundary_size - 1); + return shift + nr > boundary_size; +} + +extern unsigned long iommu_area_alloc(unsigned long *map, unsigned long size, + unsigned long start, unsigned int nr, + unsigned long shift, + unsigned long boundary_size, + unsigned long align_mask); + +static inline unsigned long iommu_num_pages(unsigned long addr, + unsigned long len, + unsigned long io_page_size) +{ + unsigned long size = (addr & (io_page_size - 1)) + len; + + return DIV_ROUND_UP(size, io_page_size); +} + +#endif |