linux: bitmap.h: Add find_next_zero_area function
authorKeerthy <j-keerthy@ti.com>
Thu, 27 Jan 2022 12:16:54 +0000 (13:16 +0100)
committerTom Rini <trini@konsulko.com>
Tue, 8 Feb 2022 16:00:03 +0000 (11:00 -0500)
Add find_next_zero_area to fetch the next zero area in the map.

Signed-off-by: Keerthy <j-keerthy@ti.com>
Signed-off-by: Amjad Ouled-Ameur <aouledameur@baylibre.com>
include/linux/bitmap.h

index dae4225..0a8503a 100644 (file)
@@ -159,6 +159,32 @@ static inline unsigned long find_first_bit(const unsigned long *addr, unsigned l
             (bit) < (size);                                    \
             (bit) = find_next_bit((addr), (size), (bit) + 1))
 
+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)
+{
+       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 end;
+       i = find_next_bit(map, end, index);
+       if (i < end) {
+               start = i + 1;
+               goto again;
+       }
+       return index;
+}
+
 static inline void bitmap_fill(unsigned long *dst, unsigned int nbits)
 {
        if (small_const_nbits(nbits)) {