| /* |
| * bitops.h: Bit string operations on the ppc |
| */ |
| |
| #ifndef _PPC_BITOPS_H |
| #define _PPC_BITOPS_H |
| |
| #include <linux/config.h> |
| #include <asm/byteorder.h> |
| |
| 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); |
| |
| /* |
| * Arguably these bit operations don't imply any memory barrier or |
| * SMP ordering, but in fact a lot of drivers expect them to imply |
| * both, since they do on x86 cpus. |
| */ |
| #ifdef CONFIG_SMP |
| #define SMP_WMB "eieio\n" |
| #define SMP_MB "\nsync" |
| #else |
| #define SMP_WMB |
| #define SMP_MB |
| #endif /* CONFIG_SMP */ |
| |
| #define __INLINE_BITOPS 1 |
| |
| #if __INLINE_BITOPS |
| /* |
| * These used to be if'd out here because using : "cc" as a constraint |
| * resulted in errors from egcs. Things may be OK with gcc-2.95. |
| */ |
| extern __inline__ void set_bit(int nr, volatile void * addr) |
| { |
| unsigned long old; |
| unsigned long mask = 1 << (nr & 0x1f); |
| unsigned long *p = ((unsigned long *)addr) + (nr >> 5); |
| |
| __asm__ __volatile__(SMP_WMB "\ |
| 1: lwarx %0,0,%3\n\ |
| or %0,%0,%2\n\ |
| stwcx. %0,0,%3\n\ |
| bne 1b" |
| SMP_MB |
| : "=&r" (old), "=m" (*p) |
| : "r" (mask), "r" (p), "m" (*p) |
| : "cc" ); |
| } |
| |
| extern __inline__ void clear_bit(int nr, volatile void *addr) |
| { |
| unsigned long old; |
| unsigned long mask = 1 << (nr & 0x1f); |
| unsigned long *p = ((unsigned long *)addr) + (nr >> 5); |
| |
| __asm__ __volatile__(SMP_WMB "\ |
| 1: lwarx %0,0,%3\n\ |
| andc %0,%0,%2\n\ |
| stwcx. %0,0,%3\n\ |
| bne 1b" |
| SMP_MB |
| : "=&r" (old), "=m" (*p) |
| : "r" (mask), "r" (p), "m" (*p) |
| : "cc"); |
| } |
| |
| extern __inline__ void change_bit(int nr, volatile void *addr) |
| { |
| unsigned long old; |
| unsigned long mask = 1 << (nr & 0x1f); |
| unsigned long *p = ((unsigned long *)addr) + (nr >> 5); |
| |
| __asm__ __volatile__(SMP_WMB "\ |
| 1: lwarx %0,0,%3\n\ |
| xor %0,%0,%2\n\ |
| stwcx. %0,0,%3\n\ |
| bne 1b" |
| SMP_MB |
| : "=&r" (old), "=m" (*p) |
| : "r" (mask), "r" (p), "m" (*p) |
| : "cc"); |
| } |
| |
| extern __inline__ int test_and_set_bit(int nr, volatile void *addr) |
| { |
| unsigned int old, t; |
| unsigned int mask = 1 << (nr & 0x1f); |
| volatile unsigned int *p = ((volatile unsigned int *)addr) + (nr >> 5); |
| |
| __asm__ __volatile__(SMP_WMB "\ |
| 1: lwarx %0,0,%4\n\ |
| or %1,%0,%3\n\ |
| stwcx. %1,0,%4\n\ |
| bne 1b" |
| SMP_MB |
| : "=&r" (old), "=&r" (t), "=m" (*p) |
| : "r" (mask), "r" (p), "m" (*p) |
| : "cc"); |
| |
| return (old & mask) != 0; |
| } |
| |
| extern __inline__ int test_and_clear_bit(int nr, volatile void *addr) |
| { |
| unsigned int old, t; |
| unsigned int mask = 1 << (nr & 0x1f); |
| volatile unsigned int *p = ((volatile unsigned int *)addr) + (nr >> 5); |
| |
| __asm__ __volatile__(SMP_WMB "\ |
| 1: lwarx %0,0,%4\n\ |
| andc %1,%0,%3\n\ |
| stwcx. %1,0,%4\n\ |
| bne 1b" |
| SMP_MB |
| : "=&r" (old), "=&r" (t), "=m" (*p) |
| : "r" (mask), "r" (p), "m" (*p) |
| : "cc"); |
| |
| return (old & mask) != 0; |
| } |
| |
| extern __inline__ int test_and_change_bit(int nr, volatile void *addr) |
| { |
| unsigned int old, t; |
| unsigned int mask = 1 << (nr & 0x1f); |
| volatile unsigned int *p = ((volatile unsigned int *)addr) + (nr >> 5); |
| |
| __asm__ __volatile__(SMP_WMB "\ |
| 1: lwarx %0,0,%4\n\ |
| xor %1,%0,%3\n\ |
| stwcx. %1,0,%4\n\ |
| bne 1b" |
| SMP_MB |
| : "=&r" (old), "=&r" (t), "=m" (*p) |
| : "r" (mask), "r" (p), "m" (*p) |
| : "cc"); |
| |
| return (old & mask) != 0; |
| } |
| #endif /* __INLINE_BITOPS */ |
| |
| extern __inline__ int test_bit(int nr, __const__ volatile void *addr) |
| { |
| __const__ unsigned int *p = (__const__ unsigned int *) addr; |
| |
| return ((p[nr >> 5] >> (nr & 0x1f)) & 1) != 0; |
| } |
| |
| /* Return the bit position of the most significant 1 bit in a word */ |
| /* - the result is undefined when x == 0 */ |
| extern __inline__ int __ilog2(unsigned int x) |
| { |
| int lz; |
| |
| asm ("cntlzw %0,%1" : "=r" (lz) : "r" (x)); |
| return 31 - lz; |
| } |
| |
| extern __inline__ int ffz(unsigned int x) |
| { |
| if ((x = ~x) == 0) |
| return 32; |
| return __ilog2(x & -x); |
| } |
| |
| /* |
| * fls: find last (most-significant) bit set. |
| * Note fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32. |
| * |
| * On powerpc, __ilog2(0) returns -1, but this is not safe in general |
| */ |
| static __inline__ int fls(unsigned int x) |
| { |
| return __ilog2(x) + 1; |
| } |
| #define fls |
| |
| /** |
| * fls64 - find last set bit in a 64-bit word |
| * @x: the word to search |
| * |
| * This is defined in a similar way as the libc and compiler builtin |
| * ffsll, but returns the position of the most significant set bit. |
| * |
| * fls64(value) returns 0 if value is 0 or the position of the last |
| * set bit if value is nonzero. The last (most significant) bit is |
| * at position 64. |
| */ |
| #if BITS_PER_LONG == 32 |
| static inline int fls64(__u64 x) |
| { |
| __u32 h = x >> 32; |
| if (h) |
| return fls(h) + 32; |
| return fls(x); |
| } |
| #elif BITS_PER_LONG == 64 |
| static inline int fls64(__u64 x) |
| { |
| if (x == 0) |
| return 0; |
| return __ilog2(x) + 1; |
| } |
| #else |
| #error BITS_PER_LONG not 32 or 64 |
| #endif |
| |
| static inline int __ilog2_u64(u64 n) |
| { |
| return fls64(n) - 1; |
| } |
| |
| static inline int ffs64(u64 x) |
| { |
| return __ilog2_u64(x & -x) + 1ull; |
| } |
| |
| #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). |
| */ |
| extern __inline__ int ffs(int x) |
| { |
| return __ilog2(x & -x) + 1; |
| } |
| #define ffs |
| |
| /* |
| * 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) |
| |
| extern __inline__ unsigned long 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 = *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 = *p++) != ~0U) |
| goto found_middle; |
| result += 32; |
| size -= 32; |
| } |
| 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) |
| |
| #else |
| extern __inline__ int ext2_set_bit(int nr, void * addr) |
| { |
| int mask; |
| unsigned char *ADDR = (unsigned char *) addr; |
| int oldbit; |
| |
| ADDR += nr >> 3; |
| mask = 1 << (nr & 0x07); |
| oldbit = (*ADDR & mask) ? 1 : 0; |
| *ADDR |= mask; |
| return oldbit; |
| } |
| |
| extern __inline__ int ext2_clear_bit(int nr, void * addr) |
| { |
| int mask; |
| unsigned char *ADDR = (unsigned char *) addr; |
| int oldbit; |
| |
| ADDR += nr >> 3; |
| mask = 1 << (nr & 0x07); |
| oldbit = (*ADDR & mask) ? 1 : 0; |
| *ADDR = *ADDR & ~mask; |
| return oldbit; |
| } |
| #endif /* __KERNEL__ */ |
| |
| extern __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) |
| |
| static __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_test_and_set_bit(nr,addr) ext2_set_bit(nr,addr) |
| #define minix_set_bit(nr,addr) ((void)ext2_set_bit(nr,addr)) |
| #define minix_test_and_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 /* _PPC_BITOPS_H */ |