android_kernel_samsung_msm8976/lib/iommu-helper.c
Akinobu Mita a66022c457 iommu-helper: use bitmap library
Use bitmap library and kill some unused iommu helper functions.

1. s/iommu_area_free/bitmap_clear/

2. s/iommu_area_reserve/bitmap_set/

3. Use bitmap_find_next_zero_area instead of find_next_zero_area

  This cannot be simple substitution because find_next_zero_area
  doesn't check the last bit of the limit in bitmap

4. Remove iommu_area_free, iommu_area_reserve, and find_next_zero_area

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-16 07:20:18 -08:00

49 lines
1.2 KiB
C

/*
* IOMMU helper functions for the free area management
*/
#include <linux/module.h>
#include <linux/bitmap.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);
unsigned long iommu_num_pages(unsigned long addr, unsigned long len,
unsigned long io_page_size)
{
unsigned long size = (addr & (io_page_size - 1)) + len;
return DIV_ROUND_UP(size, io_page_size);
}
EXPORT_SYMBOL(iommu_num_pages);