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Diffstat (limited to 'include/asm-x86_64/bitops.h')
| -rw-r--r-- | include/asm-x86_64/bitops.h | 418 |
1 files changed, 418 insertions, 0 deletions
diff --git a/include/asm-x86_64/bitops.h b/include/asm-x86_64/bitops.h new file mode 100644 index 000000000000..5dd7727c756b --- /dev/null +++ b/include/asm-x86_64/bitops.h @@ -0,0 +1,418 @@ +#ifndef _X86_64_BITOPS_H +#define _X86_64_BITOPS_H + +/* + * Copyright 1992, Linus Torvalds. + */ + +#include <linux/config.h> + +#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; +} + +#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; + if (b[2]) + 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; +} + +/** + * 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) + +#define ARCH_HAS_ATOMIC_UNSIGNED 1 + +#endif /* __KERNEL__ */ + +#endif /* _X86_64_BITOPS_H */ |