2 * IOMMU helper functions for the free area management
5 #include <linux/export.h>
6 #include <linux/bitmap.h>
9 int iommu_is_span_boundary(unsigned int index, unsigned int nr,
11 unsigned long boundary_size)
13 BUG_ON(!is_power_of_2(boundary_size));
15 shift = (shift + index) & (boundary_size - 1);
16 return shift + nr > boundary_size;
19 unsigned long iommu_area_alloc(unsigned long *map, unsigned long size,
20 unsigned long start, unsigned int nr,
21 unsigned long shift, unsigned long boundary_size,
22 unsigned long align_mask)
26 /* We don't want the last of the limit */
29 index = bitmap_find_next_zero_area(map, size, start, nr, align_mask);
31 if (iommu_is_span_boundary(index, nr, shift, boundary_size)) {
32 /* we could do more effectively */
36 bitmap_set(map, index, nr);
41 EXPORT_SYMBOL(iommu_area_alloc);