#ifndef _X86_BITOPS_H #define _X86_BITOPS_H /* * Copyright 1992, Linus Torvalds. */ #include /* * We specify the memory operand as both input and output because the memory * operand is both read from and written to. Since the operand is in fact a * word array, we also specify "memory" in the clobbers list to indicate that * words other than the one directly addressed by the memory operand may be * modified. We don't use "+m" because the gcc manual says that it should be * used only when the constraint allows the operand to reside in a register. */ #define ADDR (*(volatile long *) addr) #define CONST_ADDR (*(const volatile long *) addr) extern void __bitop_bad_size(void); #define bitop_bad_size(addr) (sizeof(*(addr)) < 4) /** * 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; btsl %1,%0" : "=m" (ADDR) : "Ir" (nr), "m" (ADDR) : "memory"); } #define set_bit(nr, addr) ({ \ if ( bitop_bad_size(addr) ) __bitop_bad_size(); \ set_bit(nr, addr); \ }) /** * __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) : "Ir" (nr), "m" (ADDR) : "memory"); } #define __set_bit(nr, addr) ({ \ if ( bitop_bad_size(addr) ) __bitop_bad_size(); \ __set_bit(nr, addr); \ }) /** * 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. */ static inline void clear_bit(int nr, volatile void *addr) { asm volatile ( "lock; btrl %1,%0" : "=m" (ADDR) : "Ir" (nr), "m" (ADDR) : "memory"); } #define clear_bit(nr, addr) ({ \ if ( bitop_bad_size(addr) ) __bitop_bad_size(); \ clear_bit(nr, addr); \ }) /** * __clear_bit - Clears a bit in memory * @nr: Bit to clear * @addr: Address to start counting from * * Unlike clear_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 __clear_bit(int nr, volatile void *addr) { asm volatile ( "btrl %1,%0" : "=m" (ADDR) : "Ir" (nr), "m" (ADDR) : "memory"); } #define __clear_bit(nr, addr) ({ \ if ( bitop_bad_size(addr) ) __bitop_bad_size(); \ __clear_bit(nr, addr); \ }) /** * __change_bit - Toggle a bit in memory * @nr: the bit to set * @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) : "Ir" (nr), "m" (ADDR) : "memory"); } #define __change_bit(nr, addr) ({ \ if ( bitop_bad_size(addr) ) __bitop_bad_size(); \ __change_bit(nr, addr); \ }) /** * change_bit - Toggle a bit in memory * @nr: Bit to clear * @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; btcl %1,%0" : "=m" (ADDR) : "Ir" (nr), "m" (ADDR) : "memory"); } #define change_bit(nr, addr) ({ \ if ( bitop_bad_size(addr) ) __bitop_bad_size(); \ change_bit(nr, addr); \ }) /** * 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; btsl %2,%1\n\tsbbl %0,%0" : "=r" (oldbit), "=m" (ADDR) : "Ir" (nr), "m" (ADDR) : "memory"); return oldbit; } #define test_and_set_bit(nr, addr) ({ \ if ( bitop_bad_size(addr) ) __bitop_bad_size(); \ test_and_set_bit(nr, addr); \ }) /** * __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 volatile ( "btsl %2,%1\n\tsbbl %0,%0" : "=r" (oldbit), "=m" (ADDR) : "Ir" (nr), "m" (ADDR) : "memory"); return oldbit; } #define __test_and_set_bit(nr, addr) ({ \ if ( bitop_bad_size(addr) ) __bitop_bad_size(); \ __test_and_set_bit(nr, addr); \ }) /** * test_and_clear_bit - Clear 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_clear_bit(int nr, volatile void *addr) { int oldbit; asm volatile ( "lock; btrl %2,%1\n\tsbbl %0,%0" : "=r" (oldbit), "=m" (ADDR) : "Ir" (nr), "m" (ADDR) : "memory"); return oldbit; } #define test_and_clear_bit(nr, addr) ({ \ if ( bitop_bad_size(addr) ) __bitop_bad_size(); \ test_and_clear_bit(nr, addr); \ }) /** * __test_and_clear_bit - Clear 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_clear_bit(int nr, volatile void *addr) { int oldbit; asm volatile ( "btrl %2,%1\n\tsbbl %0,%0" : "=r" (oldbit), "=m" (ADDR) : "Ir" (nr), "m" (ADDR) : "memory"); return oldbit; } #define __test_and_clear_bit(nr, addr) ({ \ if ( bitop_bad_size(addr) ) __bitop_bad_size(); \ __test_and_clear_bit(nr, addr); \ }) /* 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) : "Ir" (nr), "m" (ADDR) : "memory"); return oldbit; } #define __test_and_change_bit(nr, addr) ({ \ if ( bitop_bad_size(addr) ) __bitop_bad_size(); \ __test_and_change_bit(nr, addr); \ }) /** * test_and_change_bit - Change a bit and return its new 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_change_bit(int nr, volatile void *addr) { int oldbit; asm volatile ( "lock; btcl %2,%1\n\tsbbl %0,%0" : "=r" (oldbit), "=m" (ADDR) : "Ir" (nr), "m" (ADDR) : "memory"); return oldbit; } #define test_and_change_bit(nr, addr) ({ \ if ( bitop_bad_size(addr) ) __bitop_bad_size(); \ test_and_change_bit(nr, addr); \ }) static inline int constant_test_bit(int nr, const volatile void *addr) { return ((1U << (nr & 31)) & (((const volatile unsigned int *)addr)[nr >> 5])) != 0; } static inline int variable_test_bit(int nr, const volatile void *addr) { int oldbit; asm volatile ( "btl %2,%1\n\tsbbl %0,%0" : "=r" (oldbit) : "m" (CONST_ADDR), "Ir" (nr) : "memory" ); return oldbit; } #define test_bit(nr, addr) ({ \ if ( bitop_bad_size(addr) ) __bitop_bad_size(); \ (__builtin_constant_p(nr) ? \ constant_test_bit((nr),(addr)) : \ variable_test_bit((nr),(addr))); \ }) extern unsigned int __find_first_bit( const unsigned long *addr, unsigned int size); extern unsigned int __find_next_bit( const unsigned long *addr, unsigned int size, unsigned int offset); extern unsigned int __find_first_zero_bit( const unsigned long *addr, unsigned int size); extern unsigned int __find_next_zero_bit( const unsigned long *addr, unsigned int size, unsigned int offset); static inline unsigned int __scanbit(unsigned long val, unsigned long max) { asm ( "bsf %1,%0 ; cmovz %2,%0" : "=&r" (val) : "r" (val), "r" (max) ); return (unsigned int)val; } /** * 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) /** * find_next_bit - find the first 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 */ #define find_next_bit(addr, size, off) ({ \ unsigned int r__ = (size); \ unsigned int o__ = (off); \ switch ( -!__builtin_constant_p(size) | r__ ) \ { \ case 0: (void)(addr); break; \ case 1 ... BITS_PER_LONG: \ r__ = o__ + __scanbit(*(const unsigned long *)(addr) >> o__, r__); \ break; \ default: \ if ( __builtin_constant_p(off) && !o__ ) \ r__ = __find_first_bit(addr, r__); \ else \ r__ = __find_next_bit(addr, r__, o__); \ break; \ } \ r__; \ }) /** * find_first_zero_bit - find the first zero 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 zero bit, not the number of the byte * containing a bit. */ #define find_first_zero_bit(addr, size) find_next_zero_bit(addr, size, 0) /** * find_next_zero_bit - find the first zero 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 */ #define find_next_zero_bit(addr, size, off) ({ \ unsigned int r__ = (size); \ unsigned int o__ = (off); \ switch ( -!__builtin_constant_p(size) | r__ ) \ { \ case 0: (void)(addr); break; \ case 1 ... BITS_PER_LONG: \ r__ = o__ + __scanbit(~*(const unsigned long *)(addr) >> o__, r__); \ break; \ default: \ if ( __builtin_constant_p(off) && !o__ ) \ r__ = __find_first_zero_bit(addr, r__); \ else \ r__ = __find_next_zero_bit(addr, r__, o__); \ break; \ } \ r__; \ }) /** * find_first_set_bit - find the first set bit in @word * @word: the word to search * * Returns the bit-number of the first set bit. The input must *not* be zero. */ static inline unsigned int find_first_set_bit(unsigned long word) { asm ( "bsf %1,%0" : "=r" (word) : "r" (word) ); return (unsigned int)word; } /** * ffs - find first bit set * @x: the word to search * * This is defined the same way as the libc and compiler builtin ffs routines. */ static inline int ffs(unsigned long x) { long r; asm ( "bsf %1,%0\n\t" "jnz 1f\n\t" "mov $-1,%0\n" "1:" : "=r" (r) : "rm" (x)); return (int)r+1; } /** * fls - find last bit set * @x: the word to search * * This is defined the same way as ffs. */ static inline int fls(unsigned long x) { long r; asm ( "bsr %1,%0\n\t" "jnz 1f\n\t" "mov $-1,%0\n" "1:" : "=r" (r) : "rm" (x)); return (int)r+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 /* _X86_BITOPS_H */