Revision 1a59c53920eed3b2718c07286f1afe8674a7d9e6 authored by Linus Torvalds on 09 April 2016, 17:23:45 UTC, committed by Linus Torvalds on 09 April 2016, 17:23:45 UTC
Pull IOMMU fixes from Joerg Roedel:

 - compile-time fixes (warnings and failures)

 - a bug in iommu core code which could cause the group->domain pointer
   to be falsly cleared

 - fix in scatterlist handling of the ARM common DMA-API code

 - stall detection fix for the Rockchip IOMMU driver

* tag 'iommu-fixes-v4.6-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu:
  iommu/vt-d: Silence an uninitialized variable warning
  iommu/rockchip: Fix "is stall active" check
  iommu: Don't overwrite domain pointer when there is no default_domain
  iommu/dma: Restore scatterlist offsets correctly
  iommu: provide of_xlate pointer unconditionally
2 parent s 3c96888 + 0b74ecd
Raw File
iommu-helper.c
/*
 * IOMMU helper functions for the free area management
 */

#include <linux/export.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);
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