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Diffstat (limited to 'include/asm-ia64/bitops.h')
| -rw-r--r-- | include/asm-ia64/bitops.h | 410 |
1 files changed, 410 insertions, 0 deletions
diff --git a/include/asm-ia64/bitops.h b/include/asm-ia64/bitops.h new file mode 100644 index 000000000000..925d54cee475 --- /dev/null +++ b/include/asm-ia64/bitops.h @@ -0,0 +1,410 @@ +#ifndef _ASM_IA64_BITOPS_H +#define _ASM_IA64_BITOPS_H + +/* + * Copyright (C) 1998-2003 Hewlett-Packard Co + * David Mosberger-Tang <davidm@hpl.hp.com> + * + * 02/06/02 find_next_bit() and find_first_bit() added from Erich Focht's ia64 O(1) + * scheduler patch + */ + +#include <linux/compiler.h> +#include <linux/types.h> +#include <asm/bitops.h> +#include <asm/intrinsics.h> + +/** + * 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. + * + * The address must be (at least) "long" aligned. + * Note that there are driver (e.g., eepro100) which use these operations to operate on + * hw-defined data-structures, so we can't easily change these operations to force a + * bigger alignment. + * + * bit 0 is the LSB of addr; bit 32 is the LSB of (addr+1). + */ +static __inline__ void +set_bit (int nr, volatile void *addr) +{ + __u32 bit, old, new; + volatile __u32 *m; + CMPXCHG_BUGCHECK_DECL + + m = (volatile __u32 *) addr + (nr >> 5); + bit = 1 << (nr & 31); + do { + CMPXCHG_BUGCHECK(m); + old = *m; + new = old | bit; + } while (cmpxchg_acq(m, old, new) != old); +} + +/** + * __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) +{ + *((__u32 *) addr + (nr >> 5)) |= (1 << (nr & 31)); +} + +/* + * clear_bit() has "acquire" semantics. + */ +#define smp_mb__before_clear_bit() smp_mb() +#define smp_mb__after_clear_bit() do { /* skip */; } while (0) + +/** + * 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) +{ + __u32 mask, old, new; + volatile __u32 *m; + CMPXCHG_BUGCHECK_DECL + + m = (volatile __u32 *) addr + (nr >> 5); + mask = ~(1 << (nr & 31)); + do { + CMPXCHG_BUGCHECK(m); + old = *m; + new = old & mask; + } while (cmpxchg_acq(m, old, new) != old); +} + +/** + * __clear_bit - Clears a bit in memory (non-atomic version) + */ +static __inline__ void +__clear_bit (int nr, volatile void *addr) +{ + volatile __u32 *p = (__u32 *) addr + (nr >> 5); + __u32 m = 1 << (nr & 31); + *p &= ~m; +} + +/** + * 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) +{ + __u32 bit, old, new; + volatile __u32 *m; + CMPXCHG_BUGCHECK_DECL + + m = (volatile __u32 *) addr + (nr >> 5); + bit = (1 << (nr & 31)); + do { + CMPXCHG_BUGCHECK(m); + old = *m; + new = old ^ bit; + } while (cmpxchg_acq(m, old, new) != old); +} + +/** + * __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) +{ + *((__u32 *) addr + (nr >> 5)) ^= (1 << (nr & 31)); +} + +/** + * 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) +{ + __u32 bit, old, new; + volatile __u32 *m; + CMPXCHG_BUGCHECK_DECL + + m = (volatile __u32 *) addr + (nr >> 5); + bit = 1 << (nr & 31); + do { + CMPXCHG_BUGCHECK(m); + old = *m; + new = old | bit; + } while (cmpxchg_acq(m, old, new) != old); + return (old & bit) != 0; +} + +/** + * __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) +{ + __u32 *p = (__u32 *) addr + (nr >> 5); + __u32 m = 1 << (nr & 31); + int oldbitset = (*p & m) != 0; + + *p |= m; + return oldbitset; +} + +/** + * 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) +{ + __u32 mask, old, new; + volatile __u32 *m; + CMPXCHG_BUGCHECK_DECL + + m = (volatile __u32 *) addr + (nr >> 5); + mask = ~(1 << (nr & 31)); + do { + CMPXCHG_BUGCHECK(m); + old = *m; + new = old & mask; + } while (cmpxchg_acq(m, old, new) != old); + return (old & ~mask) != 0; +} + +/** + * __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) +{ + __u32 *p = (__u32 *) addr + (nr >> 5); + __u32 m = 1 << (nr & 31); + int oldbitset = *p & m; + + *p &= ~m; + return oldbitset; +} + +/** + * test_and_change_bit - Change 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_change_bit (int nr, volatile void *addr) +{ + __u32 bit, old, new; + volatile __u32 *m; + CMPXCHG_BUGCHECK_DECL + + m = (volatile __u32 *) addr + (nr >> 5); + bit = (1 << (nr & 31)); + do { + CMPXCHG_BUGCHECK(m); + old = *m; + new = old ^ bit; + } while (cmpxchg_acq(m, old, new) != old); + return (old & bit) != 0; +} + +/* + * WARNING: non atomic version. + */ +static __inline__ int +__test_and_change_bit (int nr, void *addr) +{ + __u32 old, bit = (1 << (nr & 31)); + __u32 *m = (__u32 *) addr + (nr >> 5); + + old = *m; + *m = old ^ bit; + return (old & bit) != 0; +} + +static __inline__ int +test_bit (int nr, const volatile void *addr) +{ + return 1 & (((const volatile __u32 *) addr)[nr >> 5] >> (nr & 31)); +} + +/** + * ffz - find the first zero bit in a long word + * @x: The long word to find the bit in + * + * Returns the bit-number (0..63) of the first (least significant) zero bit. Undefined if + * no zero exists, so code should check against ~0UL first... + */ +static inline unsigned long +ffz (unsigned long x) +{ + unsigned long result; + + result = ia64_popcnt(x & (~x - 1)); + return result; +} + +/** + * __ffs - find first bit in word. + * @x: The word to search + * + * Undefined if no bit exists, so code should check against 0 first. + */ +static __inline__ unsigned long +__ffs (unsigned long x) +{ + unsigned long result; + + result = ia64_popcnt((x-1) & ~x); + return result; +} + +#ifdef __KERNEL__ + +/* + * find_last_zero_bit - find the last zero bit in a 64 bit quantity + * @x: The value to search + */ +static inline unsigned long +ia64_fls (unsigned long x) +{ + long double d = x; + long exp; + + exp = ia64_getf_exp(d); + return exp - 0xffff; +} + +static inline int +fls (int x) +{ + return ia64_fls((unsigned int) 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): it operates on + * "int" values only and the result value is the bit number + 1. ffs(0) is defined to + * return zero. + */ +#define ffs(x) __builtin_ffs(x) + +/* + * hweightN: returns the hamming weight (i.e. the number + * of bits set) of a N-bit word + */ +static __inline__ unsigned long +hweight64 (unsigned long x) +{ + unsigned long result; + result = ia64_popcnt(x); + return result; +} + +#define hweight32(x) (unsigned int) hweight64((x) & 0xfffffffful) +#define hweight16(x) (unsigned int) hweight64((x) & 0xfffful) +#define hweight8(x) (unsigned int) hweight64((x) & 0xfful) + +#endif /* __KERNEL__ */ + +extern int __find_next_zero_bit (const void *addr, unsigned long size, + unsigned long offset); +extern int __find_next_bit(const void *addr, unsigned long size, + unsigned long offset); + +#define find_next_zero_bit(addr, size, offset) \ + __find_next_zero_bit((addr), (size), (offset)) +#define find_next_bit(addr, size, offset) \ + __find_next_bit((addr), (size), (offset)) + +/* + * The optimizer actually does good code for this case.. + */ +#define find_first_zero_bit(addr, size) find_next_zero_bit((addr), (size), 0) + +#define find_first_bit(addr, size) find_next_bit((addr), (size), 0) + +#ifdef __KERNEL__ + +#define __clear_bit(nr, addr) clear_bit(nr, addr) + +#define ext2_set_bit test_and_set_bit +#define ext2_set_bit_atomic(l,n,a) test_and_set_bit(n,a) +#define ext2_clear_bit test_and_clear_bit +#define ext2_clear_bit_atomic(l,n,a) test_and_clear_bit(n,a) +#define ext2_test_bit test_bit +#define ext2_find_first_zero_bit find_first_zero_bit +#define ext2_find_next_zero_bit find_next_zero_bit + +/* Bitmap functions for the minix filesystem. */ +#define minix_test_and_set_bit(nr,addr) test_and_set_bit(nr,addr) +#define minix_set_bit(nr,addr) set_bit(nr,addr) +#define minix_test_and_clear_bit(nr,addr) test_and_clear_bit(nr,addr) +#define minix_test_bit(nr,addr) test_bit(nr,addr) +#define minix_find_first_zero_bit(addr,size) find_first_zero_bit(addr,size) + +static inline int +sched_find_first_bit (unsigned long *b) +{ + if (unlikely(b[0])) + return __ffs(b[0]); + if (unlikely(b[1])) + return 64 + __ffs(b[1]); + return __ffs(b[2]) + 128; +} + +#endif /* __KERNEL__ */ + +#endif /* _ASM_IA64_BITOPS_H */ |