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/* * This file is subject to the terms and conditions of the GNU General Public * License. See the file "COPYING" in the main directory of this archive * for more details. * * Copyright (c) 1994 - 1997, 1999, 2000 Ralf Baechle (ralf@gnu.org) * Copyright (c) 2000 Silicon Graphics, Inc. */ #ifndef _ASM_BITOPS_H #define _ASM_BITOPS_H
#include <linux/types.h> #include <asm/byteorder.h> /* sigh ... */
#ifdef __KERNEL__
#include <asm/sgidefs.h> #include <asm/system.h> #include <linux/config.h>
/* * clear_bit() doesn't provide any barrier for the compiler. */ #define smp_mb__before_clear_bit() barrier() #define smp_mb__after_clear_bit() barrier()
/* * Only disable interrupt for kernel mode stuff to keep usermode stuff * that dares to use kernel include files alive. */ #define __bi_flags unsigned long flags #define __bi_cli() __cli() #define __bi_save_flags(x) __save_flags(x) #define __bi_save_and_cli(x) __save_and_cli(x) #define __bi_restore_flags(x) __restore_flags(x) #else #define __bi_flags #define __bi_cli() #define __bi_save_flags(x) #define __bi_save_and_cli(x) #define __bi_restore_flags(x) #endif /* __KERNEL__ */
#ifdef CONFIG_CPU_HAS_LLSC
#include <asm/mipsregs.h>
/* * These functions for MIPS ISA > 1 are interrupt and SMP proof and * interrupt friendly */
/* * 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. */ extern __inline__ void set_bit(int nr, volatile void *addr) { unsigned long *m = ((unsigned long *) addr) + (nr >> 5); unsigned long temp;
__asm__ __volatile__( "1:\tll\t%0, %1\t\t# set_bit\n\t" "or\t%0, %2\n\t" "sc\t%0, %1\n\t" "beqz\t%0, 1b" : "=&r" (temp), "=m" (*m) : "ir" (1UL << (nr & 0x1f)), "m" (*m)); }
/* * __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. */ extern __inline__ void __set_bit(int nr, volatile void * addr) { unsigned long * m = ((unsigned long *) addr) + (nr >> 5);
*m |= 1UL << (nr & 31); }
/* * 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. */ extern __inline__ void clear_bit(int nr, volatile void *addr) { unsigned long *m = ((unsigned long *) addr) + (nr >> 5); unsigned long temp;
__asm__ __volatile__( "1:\tll\t%0, %1\t\t# clear_bit\n\t" "and\t%0, %2\n\t" "sc\t%0, %1\n\t" "beqz\t%0, 1b\n\t" : "=&r" (temp), "=m" (*m) : "ir" (~(1UL << (nr & 0x1f))), "m" (*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. */ extern __inline__ void change_bit(int nr, volatile void *addr) { unsigned long *m = ((unsigned long *) addr) + (nr >> 5); unsigned long temp;
__asm__ __volatile__( "1:\tll\t%0, %1\t\t# change_bit\n\t" "xor\t%0, %2\n\t" "sc\t%0, %1\n\t" "beqz\t%0, 1b" : "=&r" (temp), "=m" (*m) : "ir" (1UL << (nr & 0x1f)), "m" (*m)); }
/* * __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. */ extern __inline__ void __change_bit(int nr, volatile void * addr) { unsigned long * m = ((unsigned long *) addr) + (nr >> 5);
*m ^= 1UL << (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. */ extern __inline__ int test_and_set_bit(int nr, volatile void *addr) { unsigned long *m = ((unsigned long *) addr) + (nr >> 5); unsigned long temp, res;
__asm__ __volatile__( ".set\tnoreorder\t\t# test_and_set_bit\n" "1:\tll\t%0, %1\n\t" "or\t%2, %0, %3\n\t" "sc\t%2, %1\n\t" "beqz\t%2, 1b\n\t" " and\t%2, %0, %3\n\t" ".set\treorder" : "=&r" (temp), "=m" (*m), "=&r" (res) : "r" (1UL << (nr & 0x1f)), "m" (*m) : "memory");
return res != 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. */ extern __inline__ int __test_and_set_bit(int nr, volatile void * addr) { int mask, retval; volatile int *a = addr;
a += nr >> 5; mask = 1 << (nr & 0x1f); retval = (mask & *a) != 0; *a |= mask;
return retval; }
/* * 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. */ extern __inline__ int test_and_clear_bit(int nr, volatile void *addr) { unsigned long *m = ((unsigned long *) addr) + (nr >> 5); unsigned long temp, res;
__asm__ __volatile__( ".set\tnoreorder\t\t# test_and_clear_bit\n" "1:\tll\t%0, %1\n\t" "or\t%2, %0, %3\n\t" "xor\t%2, %3\n\t" "sc\t%2, %1\n\t" "beqz\t%2, 1b\n\t" " and\t%2, %0, %3\n\t" ".set\treorder" : "=&r" (temp), "=m" (*m), "=&r" (res) : "r" (1UL << (nr & 0x1f)), "m" (*m) : "memory");
return res != 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. */ extern __inline__ int __test_and_clear_bit(int nr, volatile void * addr) { int mask, retval; volatile int *a = addr;
a += nr >> 5; mask = 1 << (nr & 0x1f); retval = (mask & *a) != 0; *a &= ~mask;
return retval; }
/* * 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. */ extern __inline__ int test_and_change_bit(int nr, volatile void *addr) { unsigned long *m = ((unsigned long *) addr) + (nr >> 5); unsigned long temp, res;
__asm__ __volatile__( ".set\tnoreorder\t\t# test_and_change_bit\n" "1:\tll\t%0, %1\n\t" "xor\t%2, %0, %3\n\t" "sc\t%2, %1\n\t" "beqz\t%2, 1b\n\t" " and\t%2, %0, %3\n\t" ".set\treorder" : "=&r" (temp), "=m" (*m), "=&r" (res) : "r" (1UL << (nr & 0x1f)), "m" (*m) : "memory");
return res != 0; }
/* * __test_and_change_bit - Change 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. */ extern __inline__ int __test_and_change_bit(int nr, volatile void * addr) { int mask, retval; volatile int *a = addr;
a += nr >> 5; mask = 1 << (nr & 0x1f); retval = (mask & *a) != 0; *a ^= mask;
return retval; }
#else /* MIPS I */
/* * 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. */ extern __inline__ void set_bit(int nr, volatile void * addr) { int mask; volatile int *a = addr; __bi_flags;
a += nr >> 5; mask = 1 << (nr & 0x1f); __bi_save_and_cli(flags); *a |= mask; __bi_restore_flags(flags); }
/* * __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. */ extern __inline__ void __set_bit(int nr, volatile void * addr) { int mask; volatile int *a = addr;
a += nr >> 5; mask = 1 << (nr & 0x1f); *a |= mask; }
/* * 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. */ extern __inline__ void clear_bit(int nr, volatile void * addr) { int mask; volatile int *a = addr; __bi_flags;
a += nr >> 5; mask = 1 << (nr & 0x1f); __bi_save_and_cli(flags); *a &= ~mask; __bi_restore_flags(flags); }
/* * 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. */ extern __inline__ void change_bit(int nr, volatile void * addr) { int mask; volatile int *a = addr; __bi_flags;
a += nr >> 5; mask = 1 << (nr & 0x1f); __bi_save_and_cli(flags); *a ^= mask; __bi_restore_flags(flags); }
/* * __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. */ extern __inline__ void __change_bit(int nr, volatile void * addr) { unsigned long * m = ((unsigned long *) addr) + (nr >> 5);
*m ^= 1UL << (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. */ extern __inline__ int test_and_set_bit(int nr, volatile void * addr) { int mask, retval; volatile int *a = addr; __bi_flags;
a += nr >> 5; mask = 1 << (nr & 0x1f); __bi_save_and_cli(flags); retval = (mask & *a) != 0; *a |= mask; __bi_restore_flags(flags);
return retval; }
/* * __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. */ extern __inline__ int __test_and_set_bit(int nr, volatile void * addr) { int mask, retval; volatile int *a = addr;
a += nr >> 5; mask = 1 << (nr & 0x1f); retval = (mask & *a) != 0; *a |= mask;
return retval; }
/* * 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. */ extern __inline__ int test_and_clear_bit(int nr, volatile void * addr) { int mask, retval; volatile int *a = addr; __bi_flags;
a += nr >> 5; mask = 1 << (nr & 0x1f); __bi_save_and_cli(flags); retval = (mask & *a) != 0; *a &= ~mask; __bi_restore_flags(flags);
return retval; }
/* * __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. */ extern __inline__ int __test_and_clear_bit(int nr, volatile void * addr) { int mask, retval; volatile int *a = addr;
a += nr >> 5; mask = 1 << (nr & 0x1f); retval = (mask & *a) != 0; *a &= ~mask;
return retval; }
/* * 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. */ extern __inline__ int test_and_change_bit(int nr, volatile void * addr) { int mask, retval; volatile int *a = addr; __bi_flags;
a += nr >> 5; mask = 1 << (nr & 0x1f); __bi_save_and_cli(flags); retval = (mask & *a) != 0; *a ^= mask; __bi_restore_flags(flags);
return retval; }
/* * __test_and_change_bit - Change 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. */ extern __inline__ int __test_and_change_bit(int nr, volatile void * addr) { int mask, retval; volatile int *a = addr;
a += nr >> 5; mask = 1 << (nr & 0x1f); retval = (mask & *a) != 0; *a ^= mask;
return retval; }
#undef __bi_flags #undef __bi_cli #undef __bi_save_flags #undef __bi_restore_flags
#endif /* MIPS I */
/* * test_bit - Determine whether a bit is set * @nr: bit number to test * @addr: Address to start counting from */ extern __inline__ int test_bit(int nr, volatile void *addr) { return ((1UL << (nr & 31)) & (((const unsigned int *) addr)[nr >> 5])) != 0; }
#ifndef __MIPSEB__
/* Little endian versions. */
/* * 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. */ extern __inline__ int find_first_zero_bit (void *addr, unsigned size) { unsigned long dummy; int res;
if (!size) return 0;
__asm__ (".set\tnoreorder\n\t" ".set\tnoat\n" "1:\tsubu\t$1,%6,%0\n\t" "blez\t$1,2f\n\t" "lw\t$1,(%5)\n\t" "addiu\t%5,4\n\t" #if (_MIPS_ISA == _MIPS_ISA_MIPS2 ) || (_MIPS_ISA == _MIPS_ISA_MIPS3 ) || \ (_MIPS_ISA == _MIPS_ISA_MIPS4 ) || (_MIPS_ISA == _MIPS_ISA_MIPS5 ) || \ (_MIPS_ISA == _MIPS_ISA_MIPS32) || (_MIPS_ISA == _MIPS_ISA_MIPS64) "beql\t%1,$1,1b\n\t" "addiu\t%0,32\n\t" #else "addiu\t%0,32\n\t" "beq\t%1,$1,1b\n\t" "nop\n\t" "subu\t%0,32\n\t" #endif #ifdef __MIPSEB__ #error "Fix this for big endian" #endif /* __MIPSEB__ */ "li\t%1,1\n" "1:\tand\t%2,$1,%1\n\t" "beqz\t%2,2f\n\t" "sll\t%1,%1,1\n\t" "bnez\t%1,1b\n\t" "add\t%0,%0,1\n\t" ".set\tat\n\t" ".set\treorder\n" "2:" : "=r" (res), "=r" (dummy), "=r" (addr) : "0" ((signed int) 0), "1" ((unsigned int) 0xffffffff), "2" (addr), "r" (size) : "$1");
return res; }
/* * 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 */ extern __inline__ int find_next_zero_bit (void * addr, int size, int offset) { unsigned int *p = ((unsigned int *) addr) + (offset >> 5); int set = 0, bit = offset & 31, res; unsigned long dummy; if (bit) { /* * Look for zero in first byte */ #ifdef __MIPSEB__ #error "Fix this for big endian byte order" #endif __asm__(".set\tnoreorder\n\t" ".set\tnoat\n" "1:\tand\t$1,%4,%1\n\t" "beqz\t$1,1f\n\t" "sll\t%1,%1,1\n\t" "bnez\t%1,1b\n\t" "addiu\t%0,1\n\t" ".set\tat\n\t" ".set\treorder\n" "1:" : "=r" (set), "=r" (dummy) : "0" (0), "1" (1 << bit), "r" (*p) : "$1"); if (set < (32 - bit)) return set + offset; set = 32 - bit; p++; } /* * No zero yet, search remaining full bytes for a zero */ res = find_first_zero_bit(p, size - 32 * (p - (unsigned int *) addr)); return offset + set + res; }
#endif /* !(__MIPSEB__) */
/* * ffz - find first zero in word. * @word: The word to search * * Undefined if no zero exists, so code should check against ~0UL first. */ extern __inline__ unsigned long ffz(unsigned long word) { unsigned int __res; unsigned int mask = 1;
__asm__ ( ".set\tnoreorder\n\t" ".set\tnoat\n\t" "move\t%0,$0\n" "1:\tand\t$1,%2,%1\n\t" "beqz\t$1,2f\n\t" "sll\t%1,1\n\t" "bnez\t%1,1b\n\t" "addiu\t%0,1\n\t" ".set\tat\n\t" ".set\treorder\n" "2:\n\t" : "=&r" (__res), "=r" (mask) : "r" (word), "1" (mask) : "$1");
return __res; }
#ifdef __KERNEL__
/** * 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). */
#define ffs(x) generic_ffs(x)
/* * 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 hweight32(x) generic_hweight32(x) #define hweight16(x) generic_hweight16(x) #define hweight8(x) generic_hweight8(x)
#endif /* __KERNEL__ */
#ifdef __MIPSEB__ /* * 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 */ extern __inline__ int find_next_zero_bit(void *addr, int size, int offset) { unsigned long *p = ((unsigned long *) addr) + (offset >> 5); unsigned long result = offset & ~31UL; unsigned long tmp;
if (offset >= size) return size; size -= result; offset &= 31UL; if (offset) { tmp = *(p++); tmp |= ~0UL >> (32-offset); if (size < 32) goto found_first; if (~tmp) goto found_middle; size -= 32; result += 32; } while (size & ~31UL) { if (~(tmp = *(p++))) goto found_middle; result += 32; size -= 32; } if (!size) return result; tmp = *p;
found_first: tmp |= ~0UL << size; found_middle: return result + ffz(tmp); }
/* Linus sez that gcc can optimize the following correctly, we'll see if this * holds on the Sparc as it does for the ALPHA. */
#if 0 /* Fool kernel-doc since it doesn't do macros yet */ /* * 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. */ extern int find_first_zero_bit (void *addr, unsigned size); #endif
#define find_first_zero_bit(addr, size) \ find_next_zero_bit((addr), (size), 0)
#endif /* (__MIPSEB__) */
/* Now for the ext2 filesystem bit operations and helper routines. */
#ifdef __MIPSEB__ extern __inline__ int ext2_set_bit(int nr, void * addr) { int mask, retval, flags; unsigned char *ADDR = (unsigned char *) addr;
ADDR += nr >> 3; mask = 1 << (nr & 0x07); save_and_cli(flags); retval = (mask & *ADDR) != 0; *ADDR |= mask; restore_flags(flags); return retval; }
extern __inline__ int ext2_clear_bit(int nr, void * addr) { int mask, retval, flags; unsigned char *ADDR = (unsigned char *) addr;
ADDR += nr >> 3; mask = 1 << (nr & 0x07); save_and_cli(flags); retval = (mask & *ADDR) != 0; *ADDR &= ~mask; restore_flags(flags); return retval; }
extern __inline__ int ext2_test_bit(int nr, const void * addr) { int mask; const unsigned char *ADDR = (const unsigned char *) addr;
ADDR += nr >> 3; mask = 1 << (nr & 0x07); return ((mask & *ADDR) != 0); }
#define ext2_find_first_zero_bit(addr, size) \ ext2_find_next_zero_bit((addr), (size), 0)
extern __inline__ unsigned long ext2_find_next_zero_bit(void *addr, unsigned long size, unsigned long offset) { unsigned long *p = ((unsigned long *) addr) + (offset >> 5); unsigned long result = offset & ~31UL; unsigned long tmp;
if (offset >= size) return size; size -= result; offset &= 31UL; if(offset) { /* We hold the little endian value in tmp, but then the * shift is illegal. So we could keep a big endian value * in tmp, like this: * * tmp = __swab32(*(p++)); * tmp |= ~0UL >> (32-offset); * * but this would decrease preformance, so we change the * shift: */ tmp = *(p++); tmp |= __swab32(~0UL >> (32-offset)); if(size < 32) goto found_first; if(~tmp) goto found_middle; size -= 32; result += 32; } while(size & ~31UL) { if(~(tmp = *(p++))) goto found_middle; result += 32; size -= 32; } if(!size) return result; tmp = *p;
found_first: /* tmp is little endian, so we would have to swab the shift, * see above. But then we have to swab tmp below for ffz, so * we might as well do this here. */ return result + ffz(__swab32(tmp) | (~0UL << size)); found_middle: return result + ffz(__swab32(tmp)); } #else /* !(__MIPSEB__) */
/* Native ext2 byte ordering, just collapse using defines. */ #define ext2_set_bit(nr, addr) test_and_set_bit((nr), (addr)) #define ext2_clear_bit(nr, addr) test_and_clear_bit((nr), (addr)) #define ext2_test_bit(nr, addr) test_bit((nr), (addr)) #define ext2_find_first_zero_bit(addr, size) find_first_zero_bit((addr), (size)) #define ext2_find_next_zero_bit(addr, size, offset) \ find_next_zero_bit((addr), (size), (offset)) #endif /* !(__MIPSEB__) */
/* * Bitmap functions for the minix filesystem. * FIXME: These assume that Minix uses the native byte/bitorder. * This limits the Minix filesystem's value for data exchange very much. */ #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)
#endif /* _ASM_BITOPS_H */
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