diff options
author | Ralf Baechle <ralf@linux-mips.org> | 2001-01-10 05:27:25 +0000 |
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committer | Ralf Baechle <ralf@linux-mips.org> | 2001-01-10 05:27:25 +0000 |
commit | c9c06167e7933d93a6e396174c68abf242294abb (patch) | |
tree | d9a8bb30663e9a3405a1ef37ffb62bc14b9f019f /include/asm-parisc/bitops.h | |
parent | f79e8cc3c34e4192a3e5ef4cc9c6542fdef703c0 (diff) |
Merge with Linux 2.4.0-test12.
Diffstat (limited to 'include/asm-parisc/bitops.h')
-rw-r--r-- | include/asm-parisc/bitops.h | 247 |
1 files changed, 247 insertions, 0 deletions
diff --git a/include/asm-parisc/bitops.h b/include/asm-parisc/bitops.h new file mode 100644 index 000000000..f3f8e0e5b --- /dev/null +++ b/include/asm-parisc/bitops.h @@ -0,0 +1,247 @@ +#ifndef _PARISC_BITOPS_H +#define _PARISC_BITOPS_H + +#include <linux/spinlock.h> +#include <asm/system.h> +#include <asm/byteorder.h> +#include <asm/atomic.h> + +#ifdef __LP64__ +# define SHIFT_PER_LONG 6 +#ifndef BITS_PER_LONG +# define BITS_PER_LONG 64 +#endif +#else +# define SHIFT_PER_LONG 5 +#ifndef BITS_PER_LONG +# define BITS_PER_LONG 32 +#endif +#endif + +#define CHOP_SHIFTCOUNT(x) ((x) & (BITS_PER_LONG - 1)) + +static __inline__ int test_and_set_bit(int nr, void * address) +{ + unsigned long mask; + unsigned long *addr = (unsigned long *) address; + int oldbit; + unsigned long flags; + + addr += (nr >> SHIFT_PER_LONG); + SPIN_LOCK_IRQSAVE(ATOMIC_HASH(addr), flags); + + mask = 1L << CHOP_SHIFTCOUNT(nr); + oldbit = (*addr & mask) ? 1 : 0; + *addr |= mask; + + SPIN_UNLOCK_IRQRESTORE(ATOMIC_HASH(addr), flags); + + return oldbit; +} + +static __inline__ int test_and_clear_bit(int nr, void * address) +{ + unsigned long mask; + unsigned long *addr = (unsigned long *) address; + int oldbit; + unsigned long flags; + + addr += (nr >> SHIFT_PER_LONG); + SPIN_LOCK_IRQSAVE(ATOMIC_HASH(addr), flags); + + mask = 1L << CHOP_SHIFTCOUNT(nr); + oldbit = (*addr & mask) ? 1 : 0; + *addr &= ~mask; + + SPIN_UNLOCK_IRQRESTORE(ATOMIC_HASH(addr), flags); + + return oldbit; +} + +static __inline__ int test_and_change_bit(int nr, void * address) +{ + unsigned long mask; + unsigned long *addr = (unsigned long *) address; + int oldbit; + unsigned long flags; + + addr += (nr >> SHIFT_PER_LONG); + SPIN_LOCK_IRQSAVE(ATOMIC_HASH(addr), flags); + + mask = 1L << CHOP_SHIFTCOUNT(nr); + oldbit = (*addr & mask) ? 1 : 0; + *addr ^= mask; + + SPIN_UNLOCK_IRQRESTORE(ATOMIC_HASH(addr), flags); + + return oldbit; +} + +/* again, the read-only case doesn't have to do any locking */ + +static __inline__ int test_bit(int nr, const volatile void *address) +{ + unsigned long mask; + unsigned long *addr = (unsigned long *) address; + + addr += (nr >> SHIFT_PER_LONG); + mask = 1L << CHOP_SHIFTCOUNT(nr); + + return !!(*addr & mask); +} + +/* sparc does this, other arch's don't -- what's the right answer? XXX */ +#define smp_mb__before_clear_bit() do { } while(0) +#define smp_mb__after_clear_bit() do { } while(0) +#define set_bit(nr,addr) ((void)test_and_set_bit(nr,addr)) +#define clear_bit(nr,addr) ((void)test_and_clear_bit(nr,addr)) +#define change_bit(nr,addr) ((void)test_and_change_bit(nr,addr)) + +/* XXX We'd need some binary search here */ + +extern __inline__ unsigned long ffz(unsigned long word) +{ + unsigned long result; + + result = 0; + while(word & 1) { + result++; + word >>= 1; + } + + return result; +} + +#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__ */ + +/* + * This implementation of find_{first,next}_zero_bit was stolen from + * Linus' asm-alpha/bitops.h. + */ +#define find_first_zero_bit(addr, size) \ + find_next_zero_bit((addr), (size), 0) + +static __inline__ unsigned long find_next_zero_bit(void * addr, unsigned long size, unsigned long offset) +{ + unsigned long * p = ((unsigned long *) addr) + (offset >> SHIFT_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)) { + if (~(tmp = *(p++))) + 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); +} + +#define _EXT2_HAVE_ASM_BITOPS_ + +#ifdef __KERNEL__ +/* + * test_and_{set,clear}_bit guarantee atomicity without + * disabling interrupts. + */ +#define ext2_set_bit(nr, addr) test_and_set_bit((nr) ^ 0x18, addr) +#define ext2_clear_bit(nr, addr) test_and_clear_bit((nr) ^ 0x18, addr) + +#endif /* __KERNEL__ */ + +static __inline__ int ext2_test_bit(int nr, __const__ void * addr) +{ + __const__ unsigned char *ADDR = (__const__ unsigned char *) addr; + + return (ADDR[nr >> 3] >> (nr & 7)) & 1; +} + +/* + * This implementation of ext2_find_{first,next}_zero_bit was stolen from + * Linus' asm-alpha/bitops.h and modified for a big-endian machine. + */ + +#define ext2_find_first_zero_bit(addr, size) \ + ext2_find_next_zero_bit((addr), (size), 0) + +extern __inline__ unsigned long ext2_find_next_zero_bit(void *addr, + unsigned long size, unsigned long offset) +{ + unsigned int *p = ((unsigned int *) addr) + (offset >> 5); + unsigned int result = offset & ~31UL; + unsigned int tmp; + + if (offset >= size) + return size; + size -= result; + offset &= 31UL; + if (offset) { + tmp = cpu_to_le32p(p++); + tmp |= ~0UL >> (32-offset); + if (size < 32) + goto found_first; + if (tmp != ~0U) + goto found_middle; + size -= 32; + result += 32; + } + while (size >= 32) { + if ((tmp = cpu_to_le32p(p++)) != ~0U) + goto found_middle; + result += 32; + size -= 32; + } + if (!size) + return result; + tmp = cpu_to_le32p(p); +found_first: + tmp |= ~0U << size; +found_middle: + return result + ffz(tmp); +} + +/* Bitmap functions for the minix filesystem. */ +#define minix_set_bit(nr,addr) ext2_set_bit(nr,addr) +#define minix_clear_bit(nr,addr) ext2_clear_bit(nr,addr) +#define minix_test_bit(nr,addr) ext2_test_bit(nr,addr) +#define minix_find_first_zero_bit(addr,size) ext2_find_first_zero_bit(addr,size) + +#endif /* _PARISC_BITOPS_H */ |