#ifndef _ASM_BITOPS_H
#define _ASM_BITOPS_H
-#include <linux/config.h>
#include <linux/compiler.h>
#include <asm/byteorder.h>
#include <asm/system.h>
#ifdef __KERNEL__
-/*
- * ffz = Find First Zero in word. Undefined if no zero exists,
- * so code should check against ~0UL first..
- */
-static inline unsigned long ffz(unsigned long word)
-{
- unsigned long result = 0;
-
- while (word & 1) {
- result++;
- word >>= 1;
- }
- return result;
-}
+#include <asm-generic/bitops/ffz.h>
/*
* clear_bit() doesn't provide any barrier for the compiler.
__constant_test_bit((nr),(addr)) : \
__test_bit((nr),(addr)))
-extern int find_next_bit(const unsigned long *addr, int size, int offset);
-
-#define find_first_bit(addr, size) find_next_bit(addr, size, 0)
-
-#define find_first_zero_bit(addr, size) \
- find_next_zero_bit((addr), (size), 0)
-
-static inline int find_next_zero_bit(const void *addr, int size, int offset)
-{
- const unsigned long *p = ((const unsigned long *) addr) + (offset >> 5);
- unsigned long result = offset & ~31UL;
- unsigned long tmp;
-
- if (offset >= size)
- return size;
- size -= result;
- offset &= 31UL;
- if (offset) {
- tmp = *(p++);
- tmp |= ~0UL >> (32-offset);
- if (size < 32)
- goto found_first;
- if (~tmp)
- goto found_middle;
- size -= 32;
- result += 32;
- }
- while (size & ~31UL) {
- if (~(tmp = *(p++)))
- goto found_middle;
- result += 32;
- size -= 32;
- }
- if (!size)
- return result;
- tmp = *p;
-
-found_first:
- tmp |= ~0UL << size;
-found_middle:
- return result + ffz(tmp);
-}
-
-#define ffs(x) generic_ffs(x)
-#define __ffs(x) (ffs(x) - 1)
+#include <asm-generic/bitops/find.h>
-/*
- * fls: find last bit set.
+/**
+ * fls - find last bit set
+ * @x: the word to search
+ *
+ * This is defined the same way as ffs:
+ * - return 32..1 to indicate bit 31..0 most significant bit set
+ * - return 0 to indicate no bits set
*/
#define fls(x) \
({ \
int bit; \
\
- asm("scan %1,gr0,%0" : "=r"(bit) : "r"(x)); \
+ asm(" subcc %1,gr0,gr0,icc0 \n" \
+ " ckne icc0,cc4 \n" \
+ " cscan.p %1,gr0,%0 ,cc4,#1 \n" \
+ " csub %0,%0,%0 ,cc4,#0 \n" \
+ " csub %2,%0,%0 ,cc4,#1 \n" \
+ : "=&r"(bit) \
+ : "r"(x), "r"(32) \
+ : "icc0", "cc4" \
+ ); \
\
- bit ? 33 - bit : bit; \
+ bit; \
})
-#define fls64(x) generic_fls64(x)
-/*
- * Every architecture must define this function. It's the fastest
- * way of searching a 140-bit bitmap where the first 100 bits are
- * unlikely to be set. It's guaranteed that at least one of the 140
- * bits is cleared.
+/**
+ * fls64 - find last bit set in a 64-bit value
+ * @n: the value to search
+ *
+ * This is defined the same way as ffs:
+ * - return 64..1 to indicate bit 63..0 most significant bit set
+ * - return 0 to indicate no bits set
*/
-static inline int sched_find_first_bit(const unsigned long *b)
+static inline __attribute__((const))
+int fls64(u64 n)
{
- if (unlikely(b[0]))
- return __ffs(b[0]);
- if (unlikely(b[1]))
- return __ffs(b[1]) + 32;
- if (unlikely(b[2]))
- return __ffs(b[2]) + 64;
- if (b[3])
- return __ffs(b[3]) + 96;
- return __ffs(b[4]) + 128;
-}
+ union {
+ u64 ll;
+ struct { u32 h, l; };
+ } _;
+ int bit, x, y;
+
+ _.ll = n;
+
+ asm(" subcc.p %3,gr0,gr0,icc0 \n"
+ " subcc %4,gr0,gr0,icc1 \n"
+ " ckne icc0,cc4 \n"
+ " ckne icc1,cc5 \n"
+ " norcr cc4,cc5,cc6 \n"
+ " csub.p %0,%0,%0 ,cc6,1 \n"
+ " orcr cc5,cc4,cc4 \n"
+ " andcr cc4,cc5,cc4 \n"
+ " cscan.p %3,gr0,%0 ,cc4,0 \n"
+ " setlos #64,%1 \n"
+ " cscan.p %4,gr0,%0 ,cc4,1 \n"
+ " setlos #32,%2 \n"
+ " csub.p %1,%0,%0 ,cc4,0 \n"
+ " csub %2,%0,%0 ,cc4,1 \n"
+ : "=&r"(bit), "=r"(x), "=r"(y)
+ : "0r"(_.h), "r"(_.l)
+ : "icc0", "icc1", "cc4", "cc5", "cc6"
+ );
+ return bit;
+}
-/*
- * hweightN: returns the hamming weight (i.e. the number
- * of bits set) of a N-bit word
+/**
+ * ffs - find first bit set
+ * @x: the word to search
+ *
+ * - return 32..1 to indicate bit 31..0 most least significant bit set
+ * - return 0 to indicate no bits set
*/
-
-#define hweight32(x) generic_hweight32(x)
-#define hweight16(x) generic_hweight16(x)
-#define hweight8(x) generic_hweight8(x)
-
-#define ext2_set_bit(nr, addr) test_and_set_bit ((nr) ^ 0x18, (addr))
-#define ext2_clear_bit(nr, addr) test_and_clear_bit((nr) ^ 0x18, (addr))
-
-#define ext2_set_bit_atomic(lock,nr,addr) ext2_set_bit((nr), addr)
-#define ext2_clear_bit_atomic(lock,nr,addr) ext2_clear_bit((nr), addr)
-
-static inline int ext2_test_bit(int nr, const volatile void * addr)
+static inline __attribute__((const))
+int ffs(int x)
{
- const volatile unsigned char *ADDR = (const unsigned char *) addr;
- int mask;
+ /* Note: (x & -x) gives us a mask that is the least significant
+ * (rightmost) 1-bit of the value in x.
+ */
+ return fls(x & -x);
+}
- ADDR += nr >> 3;
- mask = 1 << (nr & 0x07);
- return ((mask & *ADDR) != 0);
+/**
+ * __ffs - find first bit set
+ * @x: the word to search
+ *
+ * - return 31..0 to indicate bit 31..0 most least significant bit set
+ * - if no bits are set in x, the result is undefined
+ */
+static inline __attribute__((const))
+int __ffs(unsigned long x)
+{
+ int bit;
+ asm("scan %1,gr0,%0" : "=r"(bit) : "r"(x & -x));
+ return 31 - bit;
}
-#define ext2_find_first_zero_bit(addr, size) \
- ext2_find_next_zero_bit((addr), (size), 0)
+/*
+ * special slimline version of fls() for calculating ilog2_u32()
+ * - note: no protection against n == 0
+ */
+#define ARCH_HAS_ILOG2_U32
+static inline __attribute__((const))
+int __ilog2_u32(u32 n)
+{
+ int bit;
+ asm("scan %1,gr0,%0" : "=r"(bit) : "r"(n));
+ return 31 - bit;
+}
-static inline unsigned long ext2_find_next_zero_bit(const void *addr,
- unsigned long size,
- unsigned long offset)
+/*
+ * special slimline version of fls64() for calculating ilog2_u64()
+ * - note: no protection against n == 0
+ */
+#define ARCH_HAS_ILOG2_U64
+static inline __attribute__((const))
+int __ilog2_u64(u64 n)
{
- const unsigned long *p = ((const unsigned long *) addr) + (offset >> 5);
- unsigned long result = offset & ~31UL;
- unsigned long tmp;
-
- if (offset >= size)
- return size;
- size -= result;
- offset &= 31UL;
- if(offset) {
- /* We hold the little endian value in tmp, but then the
- * shift is illegal. So we could keep a big endian value
- * in tmp, like this:
- *
- * tmp = __swab32(*(p++));
- * tmp |= ~0UL >> (32-offset);
- *
- * but this would decrease preformance, so we change the
- * shift:
- */
- tmp = *(p++);
- tmp |= __swab32(~0UL >> (32-offset));
- if(size < 32)
- goto found_first;
- if(~tmp)
- goto found_middle;
- size -= 32;
- result += 32;
- }
- while(size & ~31UL) {
- if(~(tmp = *(p++)))
- goto found_middle;
- result += 32;
- size -= 32;
- }
- if(!size)
- return result;
- tmp = *p;
-
-found_first:
- /* tmp is little endian, so we would have to swab the shift,
- * see above. But then we have to swab tmp below for ffz, so
- * we might as well do this here.
- */
- return result + ffz(__swab32(tmp) | (~0UL << size));
-found_middle:
- return result + ffz(__swab32(tmp));
+ union {
+ u64 ll;
+ struct { u32 h, l; };
+ } _;
+ int bit, x, y;
+
+ _.ll = n;
+
+ asm(" subcc %3,gr0,gr0,icc0 \n"
+ " ckeq icc0,cc4 \n"
+ " cscan.p %3,gr0,%0 ,cc4,0 \n"
+ " setlos #63,%1 \n"
+ " cscan.p %4,gr0,%0 ,cc4,1 \n"
+ " setlos #31,%2 \n"
+ " csub.p %1,%0,%0 ,cc4,0 \n"
+ " csub %2,%0,%0 ,cc4,1 \n"
+ : "=&r"(bit), "=r"(x), "=r"(y)
+ : "0r"(_.h), "r"(_.l)
+ : "icc0", "cc4"
+ );
+ return bit;
}
-/* Bitmap functions for the minix filesystem. */
-#define minix_test_and_set_bit(nr,addr) ext2_set_bit(nr,addr)
-#define minix_set_bit(nr,addr) ext2_set_bit(nr,addr)
-#define minix_test_and_clear_bit(nr,addr) ext2_clear_bit(nr,addr)
-#define minix_test_bit(nr,addr) ext2_test_bit(nr,addr)
-#define minix_find_first_zero_bit(addr,size) ext2_find_first_zero_bit(addr,size)
+#include <asm-generic/bitops/sched.h>
+#include <asm-generic/bitops/hweight.h>
+
+#include <asm-generic/bitops/ext2-non-atomic.h>
+
+#define ext2_set_bit_atomic(lock,nr,addr) test_and_set_bit ((nr) ^ 0x18, (addr))
+#define ext2_clear_bit_atomic(lock,nr,addr) test_and_clear_bit((nr) ^ 0x18, (addr))
+
+#include <asm-generic/bitops/minix-le.h>
#endif /* __KERNEL__ */
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