@@ -489,6 +489,45 @@ int bitmap_allocate_region(unsigned long *bitmap, int pos, int order)
}
EXPORT_SYMBOL(bitmap_allocate_region);
+/*
+ * bitmap_find_next_zero_area_off - find a contiguous aligned zero area
+ * @map: The address to base the search on
+ * @size: The bitmap size in bits
+ * @start: The bitnumber to start searching at
+ * @nr: The number of zeroed bits we're looking for
+ * @align_mask: Alignment mask for zero area
+ * @align_offset: Alignment offset for zero area.
+ *
+ * The @align_mask should be one less than a power of 2; the effect is that
+ * the bit offset of all zero areas this function finds plus @align_offset
+ * is multiple of that power of 2.
+ */
+unsigned long bitmap_find_next_zero_area_off(unsigned long *map,
+ unsigned long size,
+ unsigned long start,
+ unsigned int nr,
+ unsigned long align_mask,
+ unsigned long align_offset)
+{
+ unsigned long index, end, i;
+again:
+ index = find_next_zero_bit(map, size, start);
+
+ /* Align allocation */
+ index = ALIGN_MASK(index + align_offset, align_mask) - align_offset;
+
+ end = index + nr;
+ if (end > size)
+ return end;
+ i = find_next_bit(map, end, index);
+ if (i < end) {
+ start = i + 1;
+ goto again;
+ }
+ return index;
+}
+EXPORT_SYMBOL(bitmap_find_next_zero_area_off)
+
#ifdef __BIG_ENDIAN
void bitmap_long_to_byte(uint8_t *bp, const unsigned long *lp, int nbits)
@@ -101,6 +101,22 @@ extern int bitmap_scnlistprintf(char *buf, unsigned int len,
extern int bitmap_find_free_region(unsigned long *bitmap, int bits, int order);
extern void bitmap_release_region(unsigned long *bitmap, int pos, int order);
extern int bitmap_allocate_region(unsigned long *bitmap, int pos, int order);
+extern unsigned long bitmap_find_next_zero_area_off(unsigned long *map,
+ unsigned long size,
+ unsigned long start,
+ unsigned int nr,
+ unsigned long align_mask,
+ unsigned long align_offset);
+
+static inline unsigned long bitmap_find_next_zero_area(unsigned long *map,
+ unsigned long size,
+ unsigned long start,
+ unsigned int nr,
+ unsigned long align_mask)
+{
+ return bitmap_find_next_zero_area_off(map, size, start, nr,
+ align_mask, 0);
+}
#define BITMAP_LAST_WORD_MASK(nbits) \
( \
@@ -55,6 +55,8 @@
#define ROUNDUP(x, a) (((x) + (a) - 1) & ~((a) - 1))
+#define ALIGN_MASK(x, mask) (((x) + (mask)) & ~(mask))
+
#define reserve_bootmem(_p,_l) ((void)0)
struct domain;