@@ -80,4 +80,21 @@ extern unsigned long find_first_zero_bit
#endif /* CONFIG_GENERIC_FIND_FIRST_BIT */
+/**
+ * find_next_clump8 - find next 8-bit clump with set bits in a memory region
+ * @clump: location to store copy of found clump
+ * @addr: address to base the search on
+ * @size: bitmap size in number of bits
+ * @offset: bit offset at which to start searching
+ *
+ * Returns the bit offset for the next set clump; the found clump value is
+ * copied to the location pointed by @clump. If no bits are set, returns @size.
+ */
+extern unsigned long find_next_clump8(unsigned long *clump,
+ const unsigned long *addr,
+ unsigned long size, unsigned long offset);
+
+#define find_first_clump8(clump, bits, size) \
+ find_next_clump8((clump), (bits), (size), 0)
+
#endif /*_ASM_GENERIC_BITOPS_FIND_H_ */
@@ -66,6 +66,8 @@
* bitmap_allocate_region(bitmap, pos, order) Allocate specified bit region
* bitmap_from_arr32(dst, buf, nbits) Copy nbits from u32[] buf to dst
* bitmap_to_arr32(buf, src, nbits) Copy nbits from buf to u32[] dst
+ * bitmap_get_value8(map, start) Get 8bit value from map at start
+ * bitmap_set_value8(map, value, start) Set 8bit value to map at start
*
* Note, bitmap_zero() and bitmap_fill() operate over the region of
* unsigned longs, that is, bits behind bitmap till the unsigned long
@@ -489,6 +491,39 @@ static inline void bitmap_from_u64(unsig
dst[1] = mask >> 32;
}
+/**
+ * bitmap_get_value8 - get an 8-bit value within a memory region
+ * @map: address to the bitmap memory region
+ * @start: bit offset of the 8-bit value; must be a multiple of 8
+ *
+ * Returns the 8-bit value located at the @start bit offset within the @src
+ * memory region.
+ */
+static inline unsigned long bitmap_get_value8(const unsigned long *map,
+ unsigned long start)
+{
+ const size_t index = BIT_WORD(start);
+ const unsigned long offset = start % BITS_PER_LONG;
+
+ return (map[index] >> offset) & 0xFF;
+}
+
+/**
+ * bitmap_set_value8 - set an 8-bit value within a memory region
+ * @map: address to the bitmap memory region
+ * @value: the 8-bit value; values wider than 8 bits may clobber bitmap
+ * @start: bit offset of the 8-bit value; must be a multiple of 8
+ */
+static inline void bitmap_set_value8(unsigned long *map, unsigned long value,
+ unsigned long start)
+{
+ const size_t index = BIT_WORD(start);
+ const unsigned long offset = start % BITS_PER_LONG;
+
+ map[index] &= ~(0xFFUL << offset);
+ map[index] |= value << offset;
+}
+
#endif /* __ASSEMBLY__ */
#endif /* __LINUX_BITMAP_H */
@@ -47,6 +47,18 @@ extern unsigned long __sw_hweight64(__u6
(bit) < (size); \
(bit) = find_next_zero_bit((addr), (size), (bit) + 1))
+/**
+ * for_each_set_clump8 - iterate over bitmap for each 8-bit clump with set bits
+ * @start: bit offset to start search and to store the current iteration offset
+ * @clump: location to store copy of current 8-bit clump
+ * @bits: bitmap address to base the search on
+ * @size: bitmap size in number of bits
+ */
+#define for_each_set_clump8(start, clump, bits, size) \
+ for ((start) = find_first_clump8(&(clump), (bits), (size)); \
+ (start) < (size); \
+ (start) = find_next_clump8(&(clump), (bits), (size), (start) + 8))
+
static inline int get_bitmask_order(unsigned int count)
{
int order;
@@ -214,3 +214,17 @@ EXPORT_SYMBOL(find_next_bit_le);
#endif
#endif /* __BIG_ENDIAN */
+
+unsigned long find_next_clump8(unsigned long *clump, const unsigned long *addr,
+ unsigned long size, unsigned long offset)
+{
+ offset = find_next_bit(addr, size, offset);
+ if (offset == size)
+ return size;
+
+ offset = round_down(offset, 8);
+ *clump = bitmap_get_value8(addr, offset);
+
+ return offset;
+}
+EXPORT_SYMBOL(find_next_clump8);