123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169 |
- /*
- * Copyright (c) 2011 The Chromium OS Authors.
- *
- * Modified from Linux arch/arm/include/asm/bitops.h
- *
- * 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_SANDBOX_BITOPS_H
- #define __ASM_SANDBOX_BITOPS_H
- #include <linux/compiler.h>
- #include <asm/system.h>
- #include <asm-generic/bitops/fls.h>
- #include <asm-generic/bitops/__fls.h>
- #include <asm-generic/bitops/fls64.h>
- #include <asm-generic/bitops/__ffs.h>
- #ifdef __KERNEL__
- #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, void *addr);
- extern void clear_bit(int nr, void *addr);
- extern void change_bit(int nr, void *addr);
- static inline void __change_bit(int nr, 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, 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, void *addr)
- {
- unsigned long __always_unused flags;
- 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, 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, void *addr)
- {
- unsigned long __always_unused flags;
- 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, void *addr);
- static inline int __test_and_change_bit(int nr, 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;
- }
- 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.
- */
- static 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..
- */
- static 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;
- }
- /*
- * 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 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 */
|