#ifndef _X86_64_BITOPS_H #define _X86_64_BITOPS_H /* * Copyright 1992, Linus Torvalds. */ #include #ifdef CONFIG_SMP #define LOCK_PREFIX "lock ; " #else #define LOCK_PREFIX "" #endif #define ADDR (*(volatile long *) addr) /** * set_bit - Atomically set a bit in memory * @nr: the bit to set * @addr: the address to start counting from * * This function is atomic and may not be reordered. See __set_bit() * if you do not require the atomic guarantees. * Note that @nr may be almost arbitrarily large; this function is not * restricted to acting on a single-word quantity. */ static __inline__ void set_bit(int nr, volatile void * addr) { __asm__ __volatile__( LOCK_PREFIX "btsl %1,%0" :"+m" (ADDR) :"dIr" (nr) : "memory"); } /** * __set_bit - Set a bit in memory * @nr: the bit to set * @addr: the address to start counting from * * Unlike set_bit(), this function is non-atomic and may be reordered. * If it's called on the same region of memory simultaneously, the effect * may be that only one operation succeeds. */ static __inline__ void __set_bit(int nr, volatile void * addr) { __asm__ volatile( "btsl %1,%0" :"+m" (ADDR) :"dIr" (nr) : "memory"); } /** * clear_bit - Clears a bit in memory * @nr: Bit to clear * @addr: Address to start counting from * * clear_bit() is atomic and may not be reordered. However, it does * not contain a memory barrier, so if it is used for locking purposes, * you should call smp_mb__before_clear_bit() and/or smp_mb__after_clear_bit() * in order to ensure changes are visible on other processors. */ static __inline__ void clear_bit(int nr, volatile void * addr) { __asm__ __volatile__( LOCK_PREFIX "btrl %1,%0" :"+m" (ADDR) :"dIr" (nr)); } static __inline__ void __clear_bit(int nr, volatile void * addr) { __asm__ __volatile__( "btrl %1,%0" :"+m" (ADDR) :"dIr" (nr)); } #define smp_mb__before_clear_bit() barrier() #define smp_mb__after_clear_bit() barrier() /** * __change_bit - Toggle a bit in memory * @nr: the bit to change * @addr: the address to start counting from * * Unlike change_bit(), this function is non-atomic and may be reordered. * If it's called on the same region of memory simultaneously, the effect * may be that only one operation succeeds. */ static __inline__ void __change_bit(int nr, volatile void * addr) { __asm__ __volatile__( "btcl %1,%0" :"+m" (ADDR) :"dIr" (nr)); } /** * change_bit - Toggle a bit in memory * @nr: Bit to change * @addr: Address to start counting from * * change_bit() is atomic and may not be reordered. * Note that @nr may be almost arbitrarily large; this function is not * restricted to acting on a single-word quantity. */ static __inline__ void change_bit(int nr, volatile void * addr) { __asm__ __volatile__( LOCK_PREFIX "btcl %1,%0" :"+m" (ADDR) :"dIr" (nr)); } /** * test_and_set_bit - Set a bit and return its old value * @nr: Bit to set * @addr: Address to count from * * This operation is atomic and cannot be reordered. * It also implies a memory barrier. */ static __inline__ int test_and_set_bit(int nr, volatile void * addr) { int oldbit; __asm__ __volatile__( LOCK_PREFIX "btsl %2,%1\n\tsbbl %0,%0" :"=r" (oldbit),"+m" (ADDR) :"dIr" (nr) : "memory"); return oldbit; } /** * __test_and_set_bit - Set a bit and return its old value * @nr: Bit to set * @addr: Address to count from * * This operation is non-atomic and can be reordered. * If two examples of this operation race, one can appear to succeed * but actually fail. You must protect multiple accesses with a lock. */ static __inline__ int __test_and_set_bit(int nr, volatile void * addr) { int oldbit; __asm__( "btsl %2,%1\n\tsbbl %0,%0" :"=r" (oldbit),"+m" (ADDR) :"dIr" (nr)); return oldbit; } /** * test_and_clear_bit - Clear a bit and return its old value * @nr: Bit to clear * @addr: Address to count from * * This operation is atomic and cannot be reordered. * It also implies a memory barrier. */ static __inline__ int test_and_clear_bit(int nr, volatile void * addr) { int oldbit; __asm__ __volatile__( LOCK_PREFIX "btrl %2,%1\n\tsbbl %0,%0" :"=r" (oldbit),"+m" (ADDR) :"dIr" (nr) : "memory"); return oldbit; } /** * __test_and_clear_bit - Clear a bit and return its old value * @nr: Bit to clear * @addr: Address to count from * * This operation is non-atomic and can be reordered. * If two examples of this operation race, one can appear to succeed * but actually fail. You must protect multiple accesses with a lock. */ static __inline__ int __test_and_clear_bit(int nr, volatile void * addr) { int oldbit; __asm__( "btrl %2,%1\n\tsbbl %0,%0" :"=r" (oldbit),"+m" (ADDR) :"dIr" (nr)); return oldbit; } /* WARNING: non atomic and it can be reordered! */ static __inline__ int __test_and_change_bit(int nr, volatile void * addr) { int oldbit; __asm__ __volatile__( "btcl %2,%1\n\tsbbl %0,%0" :"=r" (oldbit),"+m" (ADDR) :"dIr" (nr) : "memory"); return oldbit; } /** * test_and_change_bit - Change a bit and return its old value * @nr: Bit to change * @addr: Address to count from * * This operation is atomic and cannot be reordered. * It also implies a memory barrier. */ static __inline__ int test_and_change_bit(int nr, volatile void * addr) { int oldbit; __asm__ __volatile__( LOCK_PREFIX "btcl %2,%1\n\tsbbl %0,%0" :"=r" (oldbit),"+m" (ADDR) :"dIr" (nr) : "memory"); return oldbit; } #if 0 /* Fool kernel-doc since it doesn't do macros yet */ /** * test_bit - Determine whether a bit is set * @nr: bit number to test * @addr: Address to start counting from */ static int test_bit(int nr, const volatile void * addr); #endif static __inline__ int constant_test_bit(int nr, const volatile void * addr) { return ((1UL << (nr & 31)) & (((const volatile unsigned int *) addr)[nr >> 5])) != 0; } static __inline__ int variable_test_bit(int nr, volatile const void * addr) { int oldbit; __asm__ __volatile__( "btl %2,%1\n\tsbbl %0,%0" :"=r" (oldbit) :"m" (ADDR),"dIr" (nr)); return oldbit; } #define test_bit(nr,addr) \ (__builtin_constant_p(nr) ? \ constant_test_bit((nr),(addr)) : \ variable_test_bit((nr),(addr))) #undef ADDR extern long find_first_zero_bit(const unsigned long * addr, unsigned long size); extern long find_next_zero_bit (const unsigned long * addr, long size, long offset); extern long find_first_bit(const unsigned long * addr, unsigned long size); extern long find_next_bit(const unsigned long * addr, long size, long offset); /* return index of first bet set in val or max when no bit is set */ static inline unsigned long __scanbit(unsigned long val, unsigned long max) { asm("bsfq %1,%0 ; cmovz %2,%0" : "=&r" (val) : "r" (val), "r" (max)); return val; } #define find_first_bit(addr,size) \ ((__builtin_constant_p(size) && (size) <= BITS_PER_LONG ? \ (__scanbit(*(unsigned long *)addr,(size))) : \ find_first_bit(addr,size))) #define find_next_bit(addr,size,off) \ ((__builtin_constant_p(size) && (size) <= BITS_PER_LONG ? \ ((off) + (__scanbit((*(unsigned long *)addr) >> (off),(size)-(off)))) : \ find_next_bit(addr,size,off))) #define find_first_zero_bit(addr,size) \ ((__builtin_constant_p(size) && (size) <= BITS_PER_LONG ? \ (__scanbit(~*(unsigned long *)addr,(size))) : \ find_first_zero_bit(addr,size))) #define find_next_zero_bit(addr,size,off) \ ((__builtin_constant_p(size) && (size) <= BITS_PER_LONG ? \ ((off)+(__scanbit(~(((*(unsigned long *)addr)) >> (off)),(size)-(off)))) : \ find_next_zero_bit(addr,size,off))) /* * Find string of zero bits in a bitmap. -1 when not found. */ extern unsigned long find_next_zero_string(unsigned long *bitmap, long start, long nbits, int len); static inline void set_bit_string(unsigned long *bitmap, unsigned long i, int len) { unsigned long end = i + len; while (i < end) { __set_bit(i, bitmap); i++; } } static inline void __clear_bit_string(unsigned long *bitmap, unsigned long i, int len) { unsigned long end = i + len; while (i < end) { __clear_bit(i, bitmap); i++; } } /** * ffz - find first zero in word. * @word: The word to search * * Undefined if no zero exists, so code should check against ~0UL first. */ static __inline__ unsigned long ffz(unsigned long word) { __asm__("bsfq %1,%0" :"=r" (word) :"r" (~word)); return word; } /** * __ffs - find first bit in word. * @word: The word to search * * Undefined if no bit exists, so code should check against 0 first. */ static __inline__ unsigned long __ffs(unsigned long word) { __asm__("bsfq %1,%0" :"=r" (word) :"rm" (word)); return word; } /* * __fls: find last bit set. * @word: The word to search * * Undefined if no zero exists, so code should check against ~0UL first. */ static __inline__ unsigned long __fls(unsigned long word) { __asm__("bsrq %1,%0" :"=r" (word) :"rm" (word)); return word; } #ifdef __KERNEL__ static inline int sched_find_first_bit(const unsigned long *b) { if (b[0]) return __ffs(b[0]); if (b[1]) return __ffs(b[1]) + 64; return __ffs(b[2]) + 128; } /** * ffs - find first bit set * @x: the word to search * * 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) { int r; __asm__("bsfl %1,%0\n\t" "cmovzl %2,%0" : "=r" (r) : "rm" (x), "r" (-1)); return r+1; } /** * fls64 - find last bit set in 64 bit word * @x: the word to search * * This is defined the same way as fls. */ static __inline__ int fls64(__u64 x) { if (x == 0) return 0; return __fls(x) + 1; } /** * hweightN - returns the hamming weight of a N-bit word * @x: the word to weigh * * The Hamming Weight of a number is the total number of bits set in it. */ #define hweight64(x) generic_hweight64(x) #define hweight32(x) generic_hweight32(x) #define hweight16(x) generic_hweight16(x) #define hweight8(x) generic_hweight8(x) #endif /* __KERNEL__ */ #ifdef __KERNEL__ #define ext2_set_bit(nr,addr) \ __test_and_set_bit((nr),(unsigned long*)addr) #define ext2_set_bit_atomic(lock,nr,addr) \ test_and_set_bit((nr),(unsigned long*)addr) #define ext2_clear_bit(nr, addr) \ __test_and_clear_bit((nr),(unsigned long*)addr) #define ext2_clear_bit_atomic(lock,nr,addr) \ test_and_clear_bit((nr),(unsigned long*)addr) #define ext2_test_bit(nr, addr) test_bit((nr),(unsigned long*)addr) #define ext2_find_first_zero_bit(addr, size) \ find_first_zero_bit((unsigned long*)addr, size) #define ext2_find_next_zero_bit(addr, size, off) \ find_next_zero_bit((unsigned long*)addr, size, off) /* Bitmap functions for the minix filesystem. */ #define minix_test_and_set_bit(nr,addr) __test_and_set_bit(nr,(void*)addr) #define minix_set_bit(nr,addr) __set_bit(nr,(void*)addr) #define minix_test_and_clear_bit(nr,addr) __test_and_clear_bit(nr,(void*)addr) #define minix_test_bit(nr,addr) test_bit(nr,(void*)addr) #define minix_find_first_zero_bit(addr,size) \ find_first_zero_bit((void*)addr,size) /* find last set bit */ #define fls(x) generic_fls(x) #endif /* __KERNEL__ */ #endif /* _X86_64_BITOPS_H */