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#ifndef __ASM_ARM_BITOPS_H #define __ASM_ARM_BITOPS_H /* * Copyright 1995, Russell King. * Various bits and pieces copyrights include: * Linus Torvalds (test_bit). */ /* * These should be done with inline assembly. * All bit operations return 0 if the bit * was cleared before the operation and != 0 if it was not. * * bit 0 is the LSB of addr; bit 32 is the LSB of (addr+1). */ /* * Function prototypes to keep gcc -Wall happy */ extern void set_bit(int nr, volatile void * addr); extern void clear_bit(int nr, volatile void * addr); extern void change_bit(int nr, volatile void * addr); extern int test_and_set_bit(int nr, volatile void * addr); extern int test_and_clear_bit(int nr, volatile void * addr); extern int test_and_change_bit(int nr, volatile void * addr); extern int find_first_zero_bit(void * addr, unsigned size); extern int find_next_zero_bit(void * addr, int size, int offset); /* * This routine doesn't need to be atomic. */ extern __inline__ int test_bit(int nr, const void * addr) { return ((unsigned char *) addr)[nr >> 3] & (1U << (nr & 7)); } /* * ffz = Find First Zero in word. Undefined if no zero exists, * so code should check against ~0UL first.. */ extern __inline__ unsigned long ffz(unsigned long word) { int k; word = ~word; k = 31; if (word & 0x0000ffff) { k -= 16; word <<= 16; } if (word & 0x00ff0000) { k -= 8; word <<= 8; } if (word & 0x0f000000) { k -= 4; word <<= 4; } if (word & 0x30000000) { k -= 2; word <<= 2; } if (word & 0x40000000) { k -= 1; } return k; } #ifdef __KERNEL__ /* * 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). */ #define ffs(x) generic_ffs(x) /* * hweightN: returns the hamming weight (i.e. the number * of bits set) of a N-bit word */ #define hweight32(x) generic_hweight32(x) #define hweight16(x) generic_hweight16(x) #define hweight8(x) generic_hweight8(x) #endif /* __KERNEL__ */ #ifdef __KERNEL__ #define ext2_set_bit test_and_set_bit #define ext2_clear_bit test_and_clear_bit #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_set_bit(nr,addr) test_and_set_bit(nr,addr) #define minix_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 /* __KERNEL__ */ #endif /* _ARM_BITOPS_H */ |