/* * Copyright 1995, Russell King. * Various bits and pieces copyrights include: * Linus Torvalds (test_bit). * * bit 0 is the LSB of addr; bit 32 is the LSB of (addr+1). * * Please note that the code in this file should never be included * from user space. Many of these are not implemented in assembler * since they would be too costly. Also, they require priviledged * instructions (which are not available from user mode) to ensure * that they are atomic. */ #ifndef __ASM_ARM_BITOPS_H #define __ASM_ARM_BITOPS_H #if __LINUX_ARM_ARCH__ < 5 #include #include #include #else #define PLATFORM_FFS #define PLATFORM_FLS #if !IS_ENABLED(CONFIG_HAS_THUMB2) && CONFIG_IS_ENABLED(SYS_THUMB_BUILD) unsigned long __fls(unsigned long word); unsigned long __ffs(unsigned long word); int fls(unsigned int x); int ffs(int x); #else #include #include #include #include #endif #endif #include #ifdef __KERNEL__ #ifndef __ASSEMBLY__ #include #endif #include #define smp_mb__before_clear_bit() do { } while (0) #define smp_mb__after_clear_bit() do { } while (0) /* * 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); static inline void __change_bit(int nr, volatile void *addr) { unsigned long mask = BIT_MASK(nr); unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr); *p ^= mask; } static inline int __test_and_set_bit(int nr, volatile void *addr) { unsigned long mask = BIT_MASK(nr); unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr); unsigned long old = *p; *p = old | mask; return (old & mask) != 0; } static inline int test_and_set_bit(int nr, volatile void * addr) { unsigned long flags = 0; int out; local_irq_save(flags); out = __test_and_set_bit(nr, addr); local_irq_restore(flags); return out; } static inline int __test_and_clear_bit(int nr, volatile void *addr) { unsigned long mask = BIT_MASK(nr); unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr); unsigned long old = *p; *p = old & ~mask; return (old & mask) != 0; } static inline int test_and_clear_bit(int nr, volatile void * addr) { unsigned long flags = 0; int out; local_irq_save(flags); out = __test_and_clear_bit(nr, addr); local_irq_restore(flags); return out; } extern int test_and_change_bit(int nr, volatile void * addr); static inline int __test_and_change_bit(int nr, volatile void *addr) { unsigned long mask = BIT_MASK(nr); unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr); unsigned long old = *p; *p = old ^ mask; return (old & mask) != 0; } /* * This routine doesn't need to be atomic. */ static inline int test_bit(int nr, const void * addr) { return ((unsigned char *) addr)[nr >> 3] & (1U << (nr & 7)); } static inline int __ilog2(unsigned int x) { return fls(x) - 1; } #define ffz(x) __ffs(~(x)) static inline int find_next_zero_bit(void *addr, int size, int offset) { unsigned long *p = ((unsigned long *)addr) + (offset / BITS_PER_LONG); unsigned long result = offset & ~(BITS_PER_LONG - 1); unsigned long tmp; if (offset >= size) return size; size -= result; offset &= (BITS_PER_LONG - 1); if (offset) { tmp = *(p++); tmp |= ~0UL >> (BITS_PER_LONG - offset); if (size < BITS_PER_LONG) goto found_first; if (~tmp) goto found_middle; size -= BITS_PER_LONG; result += BITS_PER_LONG; } while (size & ~(BITS_PER_LONG - 1)) { tmp = *(p++); if (~tmp) goto found_middle; result += BITS_PER_LONG; size -= BITS_PER_LONG; } if (!size) return result; tmp = *p; found_first: tmp |= ~0UL << size; found_middle: return result + ffz(tmp); } /* * 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) #define find_first_zero_bit(addr, size) \ find_next_zero_bit((addr), (size), 0) #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_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 /* __KERNEL__ */ #endif /* _ARM_BITOPS_H */