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author | Peter Tyser <ptyser@xes-inc.com> | 2010-04-13 03:28:08 (GMT) |
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committer | Wolfgang Denk <wd@denx.de> | 2010-04-13 07:13:12 (GMT) |
commit | 819833af39a91fa1c1e8252862bbda6f5a602f7b (patch) | |
tree | d5c9d1628643347ab2b5a8085acfa6f96709fda3 /arch/mips/include/asm/bitops.h | |
parent | 61f2b38a17f5b21c59f2afe6cf1cbb5f28638cf9 (diff) | |
download | u-boot-819833af39a91fa1c1e8252862bbda6f5a602f7b.tar.xz |
Move architecture-specific includes to arch/$ARCH/include/asm
This helps to clean up the include/ directory so that it only contains
non-architecture-specific headers and also matches Linux's directory
layout which many U-Boot developers are already familiar with.
Signed-off-by: Peter Tyser <ptyser@xes-inc.com>
Diffstat (limited to 'arch/mips/include/asm/bitops.h')
-rw-r--r-- | arch/mips/include/asm/bitops.h | 902 |
1 files changed, 902 insertions, 0 deletions
diff --git a/arch/mips/include/asm/bitops.h b/arch/mips/include/asm/bitops.h new file mode 100644 index 0000000..1c8f4c0 --- /dev/null +++ b/arch/mips/include/asm/bitops.h @@ -0,0 +1,902 @@ +/* + * 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. + */ +static __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. + */ +static __inline__ void __set_bit(int nr, volatile void * addr) +{ + unsigned long * m = ((unsigned long *) addr) + (nr >> 5); + + *m |= 1UL << (nr & 31); +} +#define PLATFORM__SET_BIT + +/* + * 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) +{ + 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. + */ +static __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. + */ +static __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. + */ +static __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. + */ +static __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. + */ +static __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. + */ +static __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. + */ +static __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. + */ +static __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. + */ +static __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. + */ +static __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. + */ +static __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. + */ +static __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. + */ +static __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. + */ +static __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. + */ +static __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. + */ +static __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. + */ +static __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. + */ +static __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. + */ +static __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 + */ +static __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. + */ +static __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 + */ +static __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. + */ +static __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__ + +/* + * 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 + */ +static __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. + */ +static 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__ +static __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; +} + +static __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; +} + +static __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) + +static __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 */ |