#ifndef _I386_BITOPS_H #define _I386_BITOPS_H /* * Copyright 1992, Linus Torvalds. */ /** * 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(const unsigned long *addr, unsigned size) { int d0, d1, d2; int res; if (!size) return 0; /* This looks at memory. Mark it volatile to tell gcc not to move it around */ __asm__ __volatile__( "movl $-1,%%eax\n\t" "xorl %%edx,%%edx\n\t" "repe; scasl\n\t" "je 1f\n\t" "xorl -4(%%edi),%%eax\n\t" "subl $4,%%edi\n\t" "bsfl %%eax,%%edx\n" "1:\tsubl %%ebx,%%edi\n\t" "shll $3,%%edi\n\t" "addl %%edi,%%edx" :"=d" (res), "=&c" (d0), "=&D" (d1), "=&a" (d2) :"1" ((size + 31) >> 5), "2" (addr), "b" (addr) : "memory"); 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 bit number to start searching at * @size: The maximum size to search */ int find_next_zero_bit(const unsigned long *addr, int size, int offset); /** * __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__("bsfl %1,%0" :"=r" (word) :"rm" (word)); return word; } /** * find_first_bit - find the first set 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 set bit, not the number of the byte * containing a bit. */ static inline unsigned find_first_bit(const unsigned long *addr, unsigned size) { unsigned x = 0; while (x < size) { unsigned long val = *addr++; if (val) return __ffs(val) + x; x += (sizeof(*addr)<<3); } return x; } /** * find_next_bit - find the first set bit in a memory region * @addr: The address to base the search on * @offset: The bit number to start searching at * @size: The maximum size to search */ int find_next_bit(const unsigned long *addr, int size, int offset); /** * 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__("bsfl %1,%0" :"=r" (word) :"r" (~word)); return word; } #ifdef __KERNEL__ #include /** * 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" "jnz 1f\n\t" "movl $-1,%0\n" "1:" : "=r" (r) : "rm" (x)); return r+1; } /** * fls - find last bit set * @x: the word to search * * This is defined the same way as ffs(). */ static inline int fls(int x) { int r; __asm__("bsrl %1,%0\n\t" "jnz 1f\n\t" "movl $-1,%0\n" "1:" : "=r" (r) : "rm" (x)); return r+1; } #include #endif /* __KERNEL__ */ #include #ifdef __KERNEL__ #include #define ext2_set_bit_atomic(lock, nr, addr) \ test_and_set_bit((nr), (unsigned long *)addr) #define ext2_clear_bit_atomic(lock, nr, addr) \ test_and_clear_bit((nr), (unsigned long *)addr) #include #endif /* __KERNEL__ */ #endif /* _I386_BITOPS_H */