WSL2-Linux-Kernel/lib/iommu-helper.c

30 строки
755 B
C

// 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;
}