#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__ /* * Return bit number of last (most-significant) bit set. Undefined * for x==0. Bits are numbered from 0..63 (e.g., ia64_fls(9) == 3). */ static inline unsigned long ia64_fls (unsigned long x) { long double d = x; long exp; exp = ia64_getf_exp(d); return exp - 0xffff; } /* * Find the last (most significant) bit set. Returns 0 for x==0 and * bits are numbered from 1..32 (e.g., fls(9) == 4). */ static inline int fls (int t) { unsigned long x = t & 0xffffffffu; if (!x) return 0; x |= x >> 1; x |= x >> 2; x |= x >> 4; x |= x >> 8; x |= x >> 16; return ia64_popcnt(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 */