| // SPDX-License-Identifier: GPL-2.0 |
| /* |
| * IOMMU helper functions for the free area management |
| */ |
| |
| #include <linux/bitmap.h> |
| #include <linux/iommu-helper.h> |
| |
| 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) |
| { |
| unsigned long index; |
| |
| /* We don't want the last of the limit */ |
| size -= 1; |
| again: |
| index = bitmap_find_next_zero_area(map, size, start, nr, align_mask); |
| if (index < size) { |
| if (iommu_is_span_boundary(index, nr, shift, boundary_size)) { |
| start = ALIGN(shift + index, boundary_size) - shift; |
| goto again; |
| } |
| bitmap_set(map, index, nr); |
| return index; |
| } |
| return -1; |
| } |