kernel-ark/lib/iommu-helper.c
Paul Gortmaker 50af5ead3b bug.h: add include of it to various implicit C users
With bug.h currently living right in linux/kernel.h there
are files that use BUG_ON and friends but are not including
the header explicitly.  Fix them up so we can remove the
presence in kernel.h file.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2012-02-29 17:15:08 -05:00

42 lines
1.0 KiB
C

/*
* IOMMU helper functions for the free area management
*/
#include <linux/module.h>
#include <linux/bitmap.h>
#include <linux/bug.h>
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;
}
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)) {
/* we could do more effectively */
start = index + 1;
goto again;
}
bitmap_set(map, index, nr);
return index;
}
return -1;
}
EXPORT_SYMBOL(iommu_area_alloc);