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Diffstat (limited to 'arch/cris/include/asm/bitops.h')
| -rw-r--r-- | arch/cris/include/asm/bitops.h | 166 |
1 files changed, 166 insertions, 0 deletions
diff --git a/arch/cris/include/asm/bitops.h b/arch/cris/include/asm/bitops.h new file mode 100644 index 00000000000..c0e62f811e0 --- /dev/null +++ b/arch/cris/include/asm/bitops.h @@ -0,0 +1,166 @@ +/* asm/bitops.h for Linux/CRIS + * + * TODO: asm versions if speed is needed + * + * 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). + */ + +#ifndef _CRIS_BITOPS_H +#define _CRIS_BITOPS_H + +/* Currently this is unsuitable for consumption outside the kernel. */ +#ifdef __KERNEL__ + +#ifndef _LINUX_BITOPS_H +#error only <linux/bitops.h> can be included directly +#endif + +#include <arch/bitops.h> +#include <asm/system.h> +#include <asm/atomic.h> +#include <linux/compiler.h> + +/* + * 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. + */ + +#define set_bit(nr, addr) (void)test_and_set_bit(nr, addr) + +/* + * 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. + */ + +#define clear_bit(nr, addr) (void)test_and_clear_bit(nr, addr) + +/* + * change_bit - Toggle a bit in memory + * @nr: Bit to change + * @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. + */ + +#define change_bit(nr, addr) (void)test_and_change_bit(nr, addr) + +/** + * 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 unsigned long *addr) +{ + unsigned int mask, retval; + unsigned long flags; + unsigned int *adr = (unsigned int *)addr; + + adr += nr >> 5; + mask = 1 << (nr & 0x1f); + cris_atomic_save(addr, flags); + retval = (mask & *adr) != 0; + *adr |= mask; + cris_atomic_restore(addr, flags); + return retval; +} + +/* + * clear_bit() doesn't provide any barrier for the compiler. + */ +#define smp_mb__before_clear_bit() barrier() +#define smp_mb__after_clear_bit() barrier() + +/** + * test_and_clear_bit - Clear a bit and return its old value + * @nr: Bit to clear + * @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 unsigned long *addr) +{ + unsigned int mask, retval; + unsigned long flags; + unsigned int *adr = (unsigned int *)addr; + + adr += nr >> 5; + mask = 1 << (nr & 0x1f); + cris_atomic_save(addr, flags); + retval = (mask & *adr) != 0; + *adr &= ~mask; + cris_atomic_restore(addr, flags); + return retval; +} + +/** + * test_and_change_bit - Change a bit and return its old value + * @nr: Bit to change + * @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 unsigned long *addr) +{ + unsigned int mask, retval; + unsigned long flags; + unsigned int *adr = (unsigned int *)addr; + adr += nr >> 5; + mask = 1 << (nr & 0x1f); + cris_atomic_save(addr, flags); + retval = (mask & *adr) != 0; + *adr ^= mask; + cris_atomic_restore(addr, flags); + return retval; +} + +#include <asm-generic/bitops/non-atomic.h> + +/* + * Since we define it "external", it collides with the built-in + * definition, which doesn't have the same semantics. We don't want to + * use -fno-builtin, so just hide the name ffs. + */ +#define ffs kernel_ffs + +#include <asm-generic/bitops/fls.h> +#include <asm-generic/bitops/fls64.h> +#include <asm-generic/bitops/hweight.h> +#include <asm-generic/bitops/find.h> +#include <asm-generic/bitops/lock.h> + +#include <asm-generic/bitops/ext2-non-atomic.h> + +#define ext2_set_bit_atomic(l,n,a) test_and_set_bit(n,a) +#define ext2_clear_bit_atomic(l,n,a) test_and_clear_bit(n,a) + +#include <asm-generic/bitops/minix.h> +#include <asm-generic/bitops/sched.h> + +#endif /* __KERNEL__ */ + +#endif /* _CRIS_BITOPS_H */ |