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>

1 files changed, 9 insertions, 50 deletions

diff --git a/lib/iommu-helper.c b/lib/iommu-helper.c
index 75dbda03f4fb..c0251f4ad08b 100644
--- a/lib/iommu-helper.c
+++ b/lib/iommu-helper.c
@@ -3,41 +3,7 @@
  */
 
 #include <linux/module.h>
-#include <linux/bitops.h>
-
-static unsigned long find_next_zero_area(unsigned long *map,
-                                         unsigned long size,
-                                         unsigned long start,
-                                         unsigned int nr,
-                                         unsigned long align_mask)
-{
-        unsigned long index, end, i;
-again:
-        index = find_next_zero_bit(map, size, start);
-
-        /* Align allocation */
-        index = (index + align_mask) & ~align_mask;
-
-        end = index + nr;
-        if (end >= size)
-                return -1;
-        for (i = index; i < end; i++) {
-                if (test_bit(i, map)) {
-                        start = i+1;
-                        goto again;
-                }
-        }
-        return index;
-}
-
-void iommu_area_reserve(unsigned long *map, unsigned long i, int len)
-{
-        unsigned long end = i + len;
-        while (i < end) {
-                __set_bit(i, map);
-                i++;
-        }
-}
+#include <linux/bitmap.h>
 
 int iommu_is_span_boundary(unsigned int index, unsigned int nr,
                            unsigned long shift,
@@ -55,31 +21,24 @@ unsigned long iommu_area_alloc(unsigned long *map, unsigned long size,
                                unsigned long align_mask)
 {
         unsigned long index;
+
+        /* We don't want the last of the limit */
+        size -= 1;
 again:
-        index = find_next_zero_area(map, size, start, nr, align_mask);
-        if (index != -1) {
+        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;
                 }
-                iommu_area_reserve(map, index, nr);
+                bitmap_set(map, index, nr);
+                return index;
         }
-        return index;
+        return -1;
 }
 EXPORT_SYMBOL(iommu_area_alloc);
 
-void iommu_area_free(unsigned long *map, unsigned long start, unsigned int nr)
-{
-        unsigned long end = start + nr;
-
-        while (start < end) {
-                __clear_bit(start, map);
-                start++;
-        }
-}
-EXPORT_SYMBOL(iommu_area_free);
-
 unsigned long iommu_num_pages(unsigned long addr, unsigned long len,
                               unsigned long io_page_size)
 {