// 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;
}