/* * bitops.h: Bit string operations on the ppc */ #ifdef __KERNEL__ #ifndef _PPC_BITOPS_H #define _PPC_BITOPS_H #include #include #include #include /* * The test_and_*_bit operations are taken to imply a memory barrier * on SMP systems. */ #ifdef CONFIG_SMP #define SMP_WMB "eieio\n" #define SMP_MB "\nsync" #else #define SMP_WMB #define SMP_MB #endif /* CONFIG_SMP */ static __inline__ void set_bit(int nr, volatile unsigned long * addr) { unsigned long old; unsigned long mask = 1 << (nr & 0x1f); unsigned long *p = ((unsigned long *)addr) + (nr >> 5); __asm__ __volatile__("\n\ 1: lwarx %0,0,%3 \n\ or %0,%0,%2 \n" PPC405_ERR77(0,%3) " stwcx. %0,0,%3 \n\ bne- 1b" : "=&r" (old), "=m" (*p) : "r" (mask), "r" (p), "m" (*p) : "cc" ); } /* * non-atomic version */ static __inline__ void __set_bit(int nr, volatile unsigned long *addr) { unsigned long mask = 1 << (nr & 0x1f); unsigned long *p = ((unsigned long *)addr) + (nr >> 5); *p |= mask; } /* * clear_bit doesn't imply a memory barrier */ #define smp_mb__before_clear_bit() smp_mb() #define smp_mb__after_clear_bit() smp_mb() static __inline__ void clear_bit(int nr, volatile unsigned long *addr) { unsigned long old; unsigned long mask = 1 << (nr & 0x1f); unsigned long *p = ((unsigned long *)addr) + (nr >> 5); __asm__ __volatile__("\n\ 1: lwarx %0,0,%3 \n\ andc %0,%0,%2 \n" PPC405_ERR77(0,%3) " stwcx. %0,0,%3 \n\ bne- 1b" : "=&r" (old), "=m" (*p) : "r" (mask), "r" (p), "m" (*p) : "cc"); } /* * non-atomic version */ static __inline__ void __clear_bit(int nr, volatile unsigned long *addr) { unsigned long mask = 1 << (nr & 0x1f); unsigned long *p = ((unsigned long *)addr) + (nr >> 5); *p &= ~mask; } static __inline__ void change_bit(int nr, volatile unsigned long *addr) { unsigned long old; unsigned long mask = 1 << (nr & 0x1f); unsigned long *p = ((unsigned long *)addr) + (nr >> 5); __asm__ __volatile__("\n\ 1: lwarx %0,0,%3 \n\ xor %0,%0,%2 \n" PPC405_ERR77(0,%3) " stwcx. %0,0,%3 \n\ bne- 1b" : "=&r" (old), "=m" (*p) : "r" (mask), "r" (p), "m" (*p) : "cc"); } /* * non-atomic version */ static __inline__ void __change_bit(int nr, volatile unsigned long *addr) { unsigned long mask = 1 << (nr & 0x1f); unsigned long *p = ((unsigned long *)addr) + (nr >> 5); *p ^= mask; } /* * test_and_*_bit do imply a memory barrier (?) */ static __inline__ int test_and_set_bit(int nr, volatile unsigned long *addr) { unsigned int old, t; unsigned int mask = 1 << (nr & 0x1f); volatile unsigned int *p = ((volatile unsigned int *)addr) + (nr >> 5); __asm__ __volatile__(SMP_WMB "\n\ 1: lwarx %0,0,%4 \n\ or %1,%0,%3 \n" PPC405_ERR77(0,%4) " stwcx. %1,0,%4 \n\ bne 1b" SMP_MB : "=&r" (old), "=&r" (t), "=m" (*p) : "r" (mask), "r" (p), "m" (*p) : "cc", "memory"); return (old & mask) != 0; } /* * non-atomic version */ static __inline__ int __test_and_set_bit(int nr, volatile unsigned long *addr) { unsigned long mask = 1 << (nr & 0x1f); unsigned long *p = ((unsigned long *)addr) + (nr >> 5); unsigned long old = *p; *p = old | mask; return (old & mask) != 0; } static __inline__ int test_and_clear_bit(int nr, volatile unsigned long *addr) { unsigned int old, t; unsigned int mask = 1 << (nr & 0x1f); volatile unsigned int *p = ((volatile unsigned int *)addr) + (nr >> 5); __asm__ __volatile__(SMP_WMB "\n\ 1: lwarx %0,0,%4 \n\ andc %1,%0,%3 \n" PPC405_ERR77(0,%4) " stwcx. %1,0,%4 \n\ bne 1b" SMP_MB : "=&r" (old), "=&r" (t), "=m" (*p) : "r" (mask), "r" (p), "m" (*p) : "cc", "memory"); return (old & mask) != 0; } /* * non-atomic version */ static __inline__ int __test_and_clear_bit(int nr, volatile unsigned long *addr) { unsigned long mask = 1 << (nr & 0x1f); unsigned long *p = ((unsigned long *)addr) + (nr >> 5); unsigned long old = *p; *p = old & ~mask; return (old & mask) != 0; } static __inline__ int test_and_change_bit(int nr, volatile unsigned long *addr) { unsigned int old, t; unsigned int mask = 1 << (nr & 0x1f); volatile unsigned int *p = ((volatile unsigned int *)addr) + (nr >> 5); __asm__ __volatile__(SMP_WMB "\n\ 1: lwarx %0,0,%4 \n\ xor %1,%0,%3 \n" PPC405_ERR77(0,%4) " stwcx. %1,0,%4 \n\ bne 1b" SMP_MB : "=&r" (old), "=&r" (t), "=m" (*p) : "r" (mask), "r" (p), "m" (*p) : "cc", "memory"); return (old & mask) != 0; } /* * non-atomic version */ static __inline__ int __test_and_change_bit(int nr, volatile unsigned long *addr) { unsigned long mask = 1 << (nr & 0x1f); unsigned long *p = ((unsigned long *)addr) + (nr >> 5); unsigned long old = *p; *p = old ^ mask; return (old & mask) != 0; } static __inline__ int test_bit(int nr, __const__ volatile unsigned long *addr) { return ((addr[nr >> 5] >> (nr & 0x1f)) & 1) != 0; } /* Return the bit position of the most significant 1 bit in a word */ static __inline__ int __ilog2(unsigned long x) { int lz; asm ("cntlzw %0,%1" : "=r" (lz) : "r" (x)); return 31 - lz; } static __inline__ int ffz(unsigned long x) { if ((x = ~x) == 0) return 32; return __ilog2(x & -x); } static inline int __ffs(unsigned long x) { return __ilog2(x & -x); } /* * ffs: find first bit set. This is defined the same way as * the libc and compiler builtin ffs routines, therefore * differs in spirit from the above ffz (man ffs). */ static __inline__ int ffs(int x) { return __ilog2(x & -x) + 1; } /* * fls: find last (most-significant) bit set. * Note fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32. */ static __inline__ int fls(unsigned int x) { int lz; asm ("cntlzw %0,%1" : "=r" (lz) : "r" (x)); return 32 - lz; } /* * hweightN: returns the hamming weight (i.e. the number * of bits set) of a N-bit word */ #define hweight32(x) generic_hweight32(x) #define hweight16(x) generic_hweight16(x) #define hweight8(x) generic_hweight8(x) /* * Find the first bit set in a 140-bit bitmap. * The first 100 bits are unlikely to be set. */ static inline int sched_find_first_bit(const unsigned long *b) { 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; } /** * find_next_bit - find the next set bit in a memory region * @addr: The address to base the search on * @offset: The bitnumber to start searching at * @size: The maximum size to search */ static __inline__ unsigned long find_next_bit(const unsigned long *addr, unsigned long size, unsigned long offset) { unsigned int *p = ((unsigned int *) addr) + (offset >> 5); unsigned int result = offset & ~31UL; unsigned int tmp; if (offset >= size) return size; size -= result; offset &= 31UL; if (offset) { tmp = *p++; tmp &= ~0UL << offset; if (size < 32) goto found_first; if (tmp) goto found_middle; size -= 32; result += 32; } while (size >= 32) { if ((tmp = *p++) != 0) goto found_middle; result += 32; size -= 32; } if (!size) return result; tmp = *p; found_first: tmp &= ~0UL >> (32 - size); if (tmp == 0UL) /* Are any bits set? */ return result + size; /* Nope. */ found_middle: return result + __ffs(tmp); } /** * find_first_bit - find the first set bit in a memory region * @addr: The address to start the search at * @size: The maximum size to search * * Returns the bit-number of the first set bit, not the number of the byte * containing a bit. */ #define find_first_bit(addr, size) \ find_next_bit((addr), (size), 0) /* * This implementation of find_{first,next}_zero_bit was stolen from * Linus' asm-alpha/bitops.h. */ #define find_first_zero_bit(addr, size) \ find_next_zero_bit((addr), (size), 0) static __inline__ unsigned long find_next_zero_bit(const unsigned long *addr, unsigned long size, unsigned long offset) { unsigned int * p = ((unsigned int *) addr) + (offset >> 5); unsigned int result = offset & ~31UL; unsigned int 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 != ~0U) goto found_middle; size -= 32; result += 32; } while (size >= 32) { if ((tmp = *p++) != ~0U) goto found_middle; result += 32; size -= 32; } if (!size) return result; tmp = *p; found_first: tmp |= ~0UL << size; if (tmp == ~0UL) /* Are any bits zero? */ return result + size; /* Nope. */ found_middle: return result + ffz(tmp); } #define ext2_set_bit(nr, addr) __test_and_set_bit((nr) ^ 0x18, (unsigned long *)(addr)) #define ext2_set_bit_atomic(lock, nr, addr) test_and_set_bit((nr) ^ 0x18, (unsigned long *)(addr)) #define ext2_clear_bit(nr, addr) __test_and_clear_bit((nr) ^ 0x18, (unsigned long *)(addr)) #define ext2_clear_bit_atomic(lock, nr, addr) test_and_clear_bit((nr) ^ 0x18, (unsigned long *)(addr)) static __inline__ int ext2_test_bit(int nr, __const__ void * addr) { __const__ unsigned char *ADDR = (__const__ unsigned char *) addr; return (ADDR[nr >> 3] >> (nr & 7)) & 1; } /* * This implementation of ext2_find_{first,next}_zero_bit was stolen from * Linus' asm-alpha/bitops.h and modified for a big-endian machine. */ #define ext2_find_first_zero_bit(addr, size) \ ext2_find_next_zero_bit((addr), (size), 0) static __inline__ unsigned long ext2_find_next_zero_bit(const void *addr, unsigned long size, unsigned long offset) { unsigned int *p = ((unsigned int *) addr) + (offset >> 5); unsigned int result = offset & ~31UL; unsigned int tmp; if (offset >= size) return size; size -= result; offset &= 31UL; if (offset) { tmp = cpu_to_le32p(p++); tmp |= ~0UL >> (32-offset); if (size < 32) goto found_first; if (tmp != ~0U) goto found_middle; size -= 32; result += 32; } while (size >= 32) { if ((tmp = cpu_to_le32p(p++)) != ~0U) goto found_middle; result += 32; size -= 32; } if (!size) return result; tmp = cpu_to_le32p(p); found_first: tmp |= ~0U << size; if (tmp == ~0UL) /* Are any bits zero? */ return result + size; /* Nope. */ found_middle: return result + ffz(tmp); } /* 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) ((void)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) #endif /* _PPC_BITOPS_H */ #endif /* __KERNEL__ */