[PATCH v4 01/10] lib: Import few bitmap functions from Linux

Vignesh Raghavendra
2019-12-09T04:55:31Z

Import few basic bitmap functions (bitmap_{weight,fill,set,clear,or}())
and their dependencies from Linux. These are required for upcoming DMA
resource allocation support for TI's K3 SoCs.

Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Reviewed-by: Grygorii Strashko <grygorii.strashko@ti.com>
---
include/linux/bitmap.h | 133 +++++++++++++++++++++++++++++++++++++++++
include/linux/bitops.h | 12 ++++
2 files changed, 145 insertions(+)

diff --git a/include/linux/bitmap.h b/include/linux/bitmap.h
index fbbb67c8b24e..dae4225be549 100644
--- a/include/linux/bitmap.h
+++ b/include/linux/bitmap.h
@@ -5,10 +5,88 @@
#include <asm/types.h>
#include <linux/types.h>
#include <linux/bitops.h>
+#include <linux/string.h>

+#ifdef __LITTLE_ENDIAN
+#define BITMAP_MEM_ALIGNMENT 8
+#else
+#define BITMAP_MEM_ALIGNMENT (8 * sizeof(unsigned long))
+#endif
+#define BITMAP_MEM_MASK (BITMAP_MEM_ALIGNMENT - 1)
+
+#define BITMAP_FIRST_WORD_MASK(start) (~0UL << ((start) & (BITS_PER_LONG - 1)))
+#define BITMAP_LAST_WORD_MASK(nbits) (~0UL >> (-(nbits) & (BITS_PER_LONG - 1)))
#define small_const_nbits(nbits) \
(__builtin_constant_p(nbits) && (nbits) <= BITS_PER_LONG)

+static inline void
+__bitmap_or(unsigned long *dst, const unsigned long *bitmap1,
+ const unsigned long *bitmap2, unsigned int bits)
+{
+ unsigned int k;
+ unsigned int nr = BITS_TO_LONGS(bits);
+
+ for (k = 0; k < nr; k++)
+ dst[k] = bitmap1[k] | bitmap2[k];
+}
+
+static inline int
+__bitmap_weight(const unsigned long *bitmap, unsigned int bits)
+{
+ unsigned int k, lim = bits / BITS_PER_LONG;
+ int w = 0;
+
+ for (k = 0; k < lim; k++)
+ w += hweight_long(bitmap[k]);
+
+ if (bits % BITS_PER_LONG)
+ w += hweight_long(bitmap[k] & BITMAP_LAST_WORD_MASK(bits));
+
+ return w;
+}
+
+static inline void
+__bitmap_set(unsigned long *map, unsigned int start, int len)
+{
+ unsigned long *p = map + BIT_WORD(start);
+ const unsigned int size = start + len;
+ int bits_to_set = BITS_PER_LONG - (start % BITS_PER_LONG);
+ unsigned long mask_to_set = BITMAP_FIRST_WORD_MASK(start);
+
+ while (len - bits_to_set >= 0) {
+ *p |= mask_to_set;
+ len -= bits_to_set;
+ bits_to_set = BITS_PER_LONG;
+ mask_to_set = ~0UL;
+ p++;
+ }
+ if (len) {
+ mask_to_set &= BITMAP_LAST_WORD_MASK(size);
+ *p |= mask_to_set;
+ }
+}
+
+static inline void
+__bitmap_clear(unsigned long *map, unsigned int start, int len)
+{
+ unsigned long *p = map + BIT_WORD(start);
+ const unsigned int size = start + len;
+ int bits_to_clear = BITS_PER_LONG - (start % BITS_PER_LONG);
+ unsigned long mask_to_clear = BITMAP_FIRST_WORD_MASK(start);
+
+ while (len - bits_to_clear >= 0) {
+ *p &= ~mask_to_clear;
+ len -= bits_to_clear;
+ bits_to_clear = BITS_PER_LONG;
+ mask_to_clear = ~0UL;
+ p++;
+ }
+ if (len) {
+ mask_to_clear &= BITMAP_LAST_WORD_MASK(size);
+ *p &= ~mask_to_clear;
+ }
+}
+
static inline void bitmap_zero(unsigned long *dst, int nbits)
{
if (small_const_nbits(nbits)) {
@@ -81,4 +159,59 @@ 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 void bitmap_fill(unsigned long *dst, unsigned int nbits)
+{
+ if (small_const_nbits(nbits)) {
+ *dst = ~0UL;
+ } else {
+ unsigned int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long);
+
+ memset(dst, 0xff, len);
+ }
+}
+
+static inline void bitmap_or(unsigned long *dst, const unsigned long *src1,
+ const unsigned long *src2, unsigned int nbits)
+{
+ if (small_const_nbits(nbits))
+ *dst = *src1 | *src2;
+ else
+ __bitmap_or(dst, src1, src2, nbits);
+}
+
+static inline int bitmap_weight(const unsigned long *src, unsigned int nbits)
+{
+ if (small_const_nbits(nbits))
+ return hweight_long(*src & BITMAP_LAST_WORD_MASK(nbits));
+ return __bitmap_weight(src, nbits);
+}
+
+static inline void bitmap_set(unsigned long *map, unsigned int start,
+ unsigned int nbits)
+{
+ if (__builtin_constant_p(nbits) && nbits == 1)
+ __set_bit(start, map);
+ else if (__builtin_constant_p(start & BITMAP_MEM_MASK) &&
+ IS_ALIGNED(start, BITMAP_MEM_ALIGNMENT) &&
+ __builtin_constant_p(nbits & BITMAP_MEM_MASK) &&
+ IS_ALIGNED(nbits, BITMAP_MEM_ALIGNMENT))
+ memset((char *)map + start / 8, 0xff, nbits / 8);
+ else
+ __bitmap_set(map, start, nbits);
+}
+
+static inline void bitmap_clear(unsigned long *map, unsigned int start,
+ unsigned int nbits)
+{
+ if (__builtin_constant_p(nbits) && nbits == 1)
+ __clear_bit(start, map);
+ else if (__builtin_constant_p(start & BITMAP_MEM_MASK) &&
+ IS_ALIGNED(start, BITMAP_MEM_ALIGNMENT) &&
+ __builtin_constant_p(nbits & BITMAP_MEM_MASK) &&
+ IS_ALIGNED(nbits, BITMAP_MEM_ALIGNMENT))
+ memset((char *)map + start / 8, 0, nbits / 8);
+ else
+ __bitmap_clear(map, start, nbits);
+}
+
#endif /* __LINUX_BITMAP_H */
diff --git a/include/linux/bitops.h b/include/linux/bitops.h
index 259df43fb00f..a07c70fd4858 100644
--- a/include/linux/bitops.h
+++ b/include/linux/bitops.h
@@ -4,6 +4,7 @@
#include <asm/types.h>
#include <asm-generic/bitsperlong.h>
#include <linux/compiler.h>
+#include <linux/kernel.h>

#ifdef __KERNEL__
#define BIT(nr) (1UL << (nr))
@@ -133,6 +134,17 @@ static inline unsigned int generic_hweight8(unsigned int w)
return (res & 0x0F) + ((res >> 4) & 0x0F);
}

+static inline unsigned long generic_hweight64(__u64 w)
+{
+ return generic_hweight32((unsigned int)(w >> 32)) +
+ generic_hweight32((unsigned int)w);
+}
+
+static inline unsigned long hweight_long(unsigned long w)
+{
+ return sizeof(w) == 4 ? generic_hweight32(w) : generic_hweight64(w);
+}
+
#include <asm/bitops.h>

/* linux/include/asm-generic/bitops/non-atomic.h */
--
2.24.0