diff options
Diffstat (limited to 'include/asm-generic/bitops')
22 files changed, 980 insertions, 0 deletions
diff --git a/include/asm-generic/bitops/__ffs.h b/include/asm-generic/bitops/__ffs.h new file mode 100644 index 000000000..937d7c435 --- /dev/null +++ b/include/asm-generic/bitops/__ffs.h @@ -0,0 +1,43 @@ +#ifndef _ASM_GENERIC_BITOPS___FFS_H_ +#define _ASM_GENERIC_BITOPS___FFS_H_ + +#include <asm/types.h> + +/** + * __ffs - find first bit in word. + * @word: The word to search + * + * Undefined if no bit exists, so code should check against 0 first. + */ +static __always_inline unsigned long __ffs(unsigned long word) +{ + int num = 0; + +#if BITS_PER_LONG == 64 + if ((word & 0xffffffff) == 0) { + num += 32; + word >>= 32; + } +#endif + if ((word & 0xffff) == 0) { + num += 16; + word >>= 16; + } + if ((word & 0xff) == 0) { + num += 8; + word >>= 8; + } + if ((word & 0xf) == 0) { + num += 4; + word >>= 4; + } + if ((word & 0x3) == 0) { + num += 2; + word >>= 2; + } + if ((word & 0x1) == 0) + num += 1; + return num; +} + +#endif /* _ASM_GENERIC_BITOPS___FFS_H_ */ diff --git a/include/asm-generic/bitops/__fls.h b/include/asm-generic/bitops/__fls.h new file mode 100644 index 000000000..a60a7ccb6 --- /dev/null +++ b/include/asm-generic/bitops/__fls.h @@ -0,0 +1,43 @@ +#ifndef _ASM_GENERIC_BITOPS___FLS_H_ +#define _ASM_GENERIC_BITOPS___FLS_H_ + +#include <asm/types.h> + +/** + * __fls - find last (most-significant) set bit in a long word + * @word: the word to search + * + * Undefined if no set bit exists, so code should check against 0 first. + */ +static __always_inline unsigned long __fls(unsigned long word) +{ + int num = BITS_PER_LONG - 1; + +#if BITS_PER_LONG == 64 + if (!(word & (~0ul << 32))) { + num -= 32; + word <<= 32; + } +#endif + if (!(word & (~0ul << (BITS_PER_LONG-16)))) { + num -= 16; + word <<= 16; + } + if (!(word & (~0ul << (BITS_PER_LONG-8)))) { + num -= 8; + word <<= 8; + } + if (!(word & (~0ul << (BITS_PER_LONG-4)))) { + num -= 4; + word <<= 4; + } + if (!(word & (~0ul << (BITS_PER_LONG-2)))) { + num -= 2; + word <<= 2; + } + if (!(word & (~0ul << (BITS_PER_LONG-1)))) + num -= 1; + return num; +} + +#endif /* _ASM_GENERIC_BITOPS___FLS_H_ */ diff --git a/include/asm-generic/bitops/arch_hweight.h b/include/asm-generic/bitops/arch_hweight.h new file mode 100644 index 000000000..6a211f406 --- /dev/null +++ b/include/asm-generic/bitops/arch_hweight.h @@ -0,0 +1,25 @@ +#ifndef _ASM_GENERIC_BITOPS_ARCH_HWEIGHT_H_ +#define _ASM_GENERIC_BITOPS_ARCH_HWEIGHT_H_ + +#include <asm/types.h> + +static inline unsigned int __arch_hweight32(unsigned int w) +{ + return __sw_hweight32(w); +} + +static inline unsigned int __arch_hweight16(unsigned int w) +{ + return __sw_hweight16(w); +} + +static inline unsigned int __arch_hweight8(unsigned int w) +{ + return __sw_hweight8(w); +} + +static inline unsigned long __arch_hweight64(__u64 w) +{ + return __sw_hweight64(w); +} +#endif /* _ASM_GENERIC_BITOPS_HWEIGHT_H_ */ diff --git a/include/asm-generic/bitops/atomic.h b/include/asm-generic/bitops/atomic.h new file mode 100644 index 000000000..49673510b --- /dev/null +++ b/include/asm-generic/bitops/atomic.h @@ -0,0 +1,189 @@ +#ifndef _ASM_GENERIC_BITOPS_ATOMIC_H_ +#define _ASM_GENERIC_BITOPS_ATOMIC_H_ + +#include <asm/types.h> +#include <linux/irqflags.h> + +#ifdef CONFIG_SMP +#include <asm/spinlock.h> +#include <asm/cache.h> /* we use L1_CACHE_BYTES */ + +/* Use an array of spinlocks for our atomic_ts. + * Hash function to index into a different SPINLOCK. + * Since "a" is usually an address, use one spinlock per cacheline. + */ +# define ATOMIC_HASH_SIZE 4 +# define ATOMIC_HASH(a) (&(__atomic_hash[ (((unsigned long) a)/L1_CACHE_BYTES) & (ATOMIC_HASH_SIZE-1) ])) + +extern arch_spinlock_t __atomic_hash[ATOMIC_HASH_SIZE] __lock_aligned; + +/* Can't use raw_spin_lock_irq because of #include problems, so + * this is the substitute */ +#define _atomic_spin_lock_irqsave(l,f) do { \ + arch_spinlock_t *s = ATOMIC_HASH(l); \ + local_irq_save(f); \ + arch_spin_lock(s); \ +} while(0) + +#define _atomic_spin_unlock_irqrestore(l,f) do { \ + arch_spinlock_t *s = ATOMIC_HASH(l); \ + arch_spin_unlock(s); \ + local_irq_restore(f); \ +} while(0) + + +#else +# define _atomic_spin_lock_irqsave(l,f) do { local_irq_save(f); } while (0) +# define _atomic_spin_unlock_irqrestore(l,f) do { local_irq_restore(f); } while (0) +#endif + +/* + * NMI events can occur at any time, including when interrupts have been + * disabled by *_irqsave(). So you can get NMI events occurring while a + * *_bit function is holding a spin lock. If the NMI handler also wants + * to do bit manipulation (and they do) then you can get a deadlock + * between the original caller of *_bit() and the NMI handler. + * + * by Keith Owens + */ + +/** + * 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: there are no guarantees that this function will not be reordered + * on non x86 architectures, so if you are writing portable code, + * make sure not to rely on its reordering guarantees. + * + * Note that @nr may be almost arbitrarily large; this function is not + * restricted to acting on a single-word quantity. + */ +static inline void set_bit(int nr, volatile unsigned long *addr) +{ + unsigned long mask = BIT_MASK(nr); + unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr); + unsigned long flags; + + _atomic_spin_lock_irqsave(p, flags); + *p |= mask; + _atomic_spin_unlock_irqrestore(p, flags); +} + +/** + * 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_atomic() and/or smp_mb__after_atomic() + * in order to ensure changes are visible on other processors. + */ +static inline void clear_bit(int nr, volatile unsigned long *addr) +{ + unsigned long mask = BIT_MASK(nr); + unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr); + unsigned long flags; + + _atomic_spin_lock_irqsave(p, flags); + *p &= ~mask; + _atomic_spin_unlock_irqrestore(p, flags); +} + +/** + * 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. It may be + * reordered on other architectures than x86. + * Note that @nr may be almost arbitrarily large; this function is not + * restricted to acting on a single-word quantity. + */ +static inline void change_bit(int nr, volatile unsigned long *addr) +{ + unsigned long mask = BIT_MASK(nr); + unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr); + unsigned long flags; + + _atomic_spin_lock_irqsave(p, flags); + *p ^= mask; + _atomic_spin_unlock_irqrestore(p, flags); +} + +/** + * 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 may be reordered on other architectures than x86. + * It also implies a memory barrier. + */ +static inline int test_and_set_bit(int nr, volatile unsigned long *addr) +{ + unsigned long mask = BIT_MASK(nr); + unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr); + unsigned long old; + unsigned long flags; + + _atomic_spin_lock_irqsave(p, flags); + old = *p; + *p = old | mask; + _atomic_spin_unlock_irqrestore(p, flags); + + return (old & mask) != 0; +} + +/** + * 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 can be reorderdered on other architectures other than x86. + * It also implies a memory barrier. + */ +static inline int test_and_clear_bit(int nr, volatile unsigned long *addr) +{ + unsigned long mask = BIT_MASK(nr); + unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr); + unsigned long old; + unsigned long flags; + + _atomic_spin_lock_irqsave(p, flags); + old = *p; + *p = old & ~mask; + _atomic_spin_unlock_irqrestore(p, flags); + + return (old & mask) != 0; +} + +/** + * 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 long mask = BIT_MASK(nr); + unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr); + unsigned long old; + unsigned long flags; + + _atomic_spin_lock_irqsave(p, flags); + old = *p; + *p = old ^ mask; + _atomic_spin_unlock_irqrestore(p, flags); + + return (old & mask) != 0; +} + +#endif /* _ASM_GENERIC_BITOPS_ATOMIC_H */ diff --git a/include/asm-generic/bitops/builtin-__ffs.h b/include/asm-generic/bitops/builtin-__ffs.h new file mode 100644 index 000000000..90041e3a4 --- /dev/null +++ b/include/asm-generic/bitops/builtin-__ffs.h @@ -0,0 +1,15 @@ +#ifndef _ASM_GENERIC_BITOPS_BUILTIN___FFS_H_ +#define _ASM_GENERIC_BITOPS_BUILTIN___FFS_H_ + +/** + * __ffs - find first bit in word. + * @word: The word to search + * + * Undefined if no bit exists, so code should check against 0 first. + */ +static __always_inline unsigned long __ffs(unsigned long word) +{ + return __builtin_ctzl(word); +} + +#endif diff --git a/include/asm-generic/bitops/builtin-__fls.h b/include/asm-generic/bitops/builtin-__fls.h new file mode 100644 index 000000000..0248f3866 --- /dev/null +++ b/include/asm-generic/bitops/builtin-__fls.h @@ -0,0 +1,15 @@ +#ifndef _ASM_GENERIC_BITOPS_BUILTIN___FLS_H_ +#define _ASM_GENERIC_BITOPS_BUILTIN___FLS_H_ + +/** + * __fls - find last (most-significant) set bit in a long word + * @word: the word to search + * + * Undefined if no set bit exists, so code should check against 0 first. + */ +static __always_inline unsigned long __fls(unsigned long word) +{ + return (sizeof(word) * 8) - 1 - __builtin_clzl(word); +} + +#endif diff --git a/include/asm-generic/bitops/builtin-ffs.h b/include/asm-generic/bitops/builtin-ffs.h new file mode 100644 index 000000000..064825829 --- /dev/null +++ b/include/asm-generic/bitops/builtin-ffs.h @@ -0,0 +1,17 @@ +#ifndef _ASM_GENERIC_BITOPS_BUILTIN_FFS_H_ +#define _ASM_GENERIC_BITOPS_BUILTIN_FFS_H_ + +/** + * ffs - find first bit set + * @x: the word to search + * + * This is defined the same way as + * the libc and compiler builtin ffs routines, therefore + * differs in spirit from the above ffz (man ffs). + */ +static __always_inline int ffs(int x) +{ + return __builtin_ffs(x); +} + +#endif diff --git a/include/asm-generic/bitops/builtin-fls.h b/include/asm-generic/bitops/builtin-fls.h new file mode 100644 index 000000000..eda652d0a --- /dev/null +++ b/include/asm-generic/bitops/builtin-fls.h @@ -0,0 +1,16 @@ +#ifndef _ASM_GENERIC_BITOPS_BUILTIN_FLS_H_ +#define _ASM_GENERIC_BITOPS_BUILTIN_FLS_H_ + +/** + * fls - find last (most-significant) bit set + * @x: the word to search + * + * This is defined the same way as ffs. + * Note fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32. + */ +static __always_inline int fls(int x) +{ + return x ? sizeof(x) * 8 - __builtin_clz(x) : 0; +} + +#endif diff --git a/include/asm-generic/bitops/const_hweight.h b/include/asm-generic/bitops/const_hweight.h new file mode 100644 index 000000000..0a7e06623 --- /dev/null +++ b/include/asm-generic/bitops/const_hweight.h @@ -0,0 +1,43 @@ +#ifndef _ASM_GENERIC_BITOPS_CONST_HWEIGHT_H_ +#define _ASM_GENERIC_BITOPS_CONST_HWEIGHT_H_ + +/* + * Compile time versions of __arch_hweightN() + */ +#define __const_hweight8(w) \ + ((unsigned int) \ + ((!!((w) & (1ULL << 0))) + \ + (!!((w) & (1ULL << 1))) + \ + (!!((w) & (1ULL << 2))) + \ + (!!((w) & (1ULL << 3))) + \ + (!!((w) & (1ULL << 4))) + \ + (!!((w) & (1ULL << 5))) + \ + (!!((w) & (1ULL << 6))) + \ + (!!((w) & (1ULL << 7))))) + +#define __const_hweight16(w) (__const_hweight8(w) + __const_hweight8((w) >> 8 )) +#define __const_hweight32(w) (__const_hweight16(w) + __const_hweight16((w) >> 16)) +#define __const_hweight64(w) (__const_hweight32(w) + __const_hweight32((w) >> 32)) + +/* + * Generic interface. + */ +#define hweight8(w) (__builtin_constant_p(w) ? __const_hweight8(w) : __arch_hweight8(w)) +#define hweight16(w) (__builtin_constant_p(w) ? __const_hweight16(w) : __arch_hweight16(w)) +#define hweight32(w) (__builtin_constant_p(w) ? __const_hweight32(w) : __arch_hweight32(w)) +#define hweight64(w) (__builtin_constant_p(w) ? __const_hweight64(w) : __arch_hweight64(w)) + +/* + * Interface for known constant arguments + */ +#define HWEIGHT8(w) (BUILD_BUG_ON_ZERO(!__builtin_constant_p(w)) + __const_hweight8(w)) +#define HWEIGHT16(w) (BUILD_BUG_ON_ZERO(!__builtin_constant_p(w)) + __const_hweight16(w)) +#define HWEIGHT32(w) (BUILD_BUG_ON_ZERO(!__builtin_constant_p(w)) + __const_hweight32(w)) +#define HWEIGHT64(w) (BUILD_BUG_ON_ZERO(!__builtin_constant_p(w)) + __const_hweight64(w)) + +/* + * Type invariant interface to the compile time constant hweight functions. + */ +#define HWEIGHT(w) HWEIGHT64((u64)w) + +#endif /* _ASM_GENERIC_BITOPS_CONST_HWEIGHT_H_ */ diff --git a/include/asm-generic/bitops/count_zeros.h b/include/asm-generic/bitops/count_zeros.h new file mode 100644 index 000000000..97520d21f --- /dev/null +++ b/include/asm-generic/bitops/count_zeros.h @@ -0,0 +1,57 @@ +/* Count leading and trailing zeros functions + * + * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public Licence + * as published by the Free Software Foundation; either version + * 2 of the Licence, or (at your option) any later version. + */ + +#ifndef _ASM_GENERIC_BITOPS_COUNT_ZEROS_H_ +#define _ASM_GENERIC_BITOPS_COUNT_ZEROS_H_ + +#include <asm/bitops.h> + +/** + * count_leading_zeros - Count the number of zeros from the MSB back + * @x: The value + * + * Count the number of leading zeros from the MSB going towards the LSB in @x. + * + * If the MSB of @x is set, the result is 0. + * If only the LSB of @x is set, then the result is BITS_PER_LONG-1. + * If @x is 0 then the result is COUNT_LEADING_ZEROS_0. + */ +static inline int count_leading_zeros(unsigned long x) +{ + if (sizeof(x) == 4) + return BITS_PER_LONG - fls(x); + else + return BITS_PER_LONG - fls64(x); +} + +#define COUNT_LEADING_ZEROS_0 BITS_PER_LONG + +/** + * count_trailing_zeros - Count the number of zeros from the LSB forwards + * @x: The value + * + * Count the number of trailing zeros from the LSB going towards the MSB in @x. + * + * If the LSB of @x is set, the result is 0. + * If only the MSB of @x is set, then the result is BITS_PER_LONG-1. + * If @x is 0 then the result is COUNT_TRAILING_ZEROS_0. + */ +static inline int count_trailing_zeros(unsigned long x) +{ +#define COUNT_TRAILING_ZEROS_0 (-1) + + if (sizeof(x) == 4) + return ffs(x); + else + return (x != 0) ? __ffs(x) : COUNT_TRAILING_ZEROS_0; +} + +#endif /* _ASM_GENERIC_BITOPS_COUNT_ZEROS_H_ */ diff --git a/include/asm-generic/bitops/ext2-atomic-setbit.h b/include/asm-generic/bitops/ext2-atomic-setbit.h new file mode 100644 index 000000000..5a0997857 --- /dev/null +++ b/include/asm-generic/bitops/ext2-atomic-setbit.h @@ -0,0 +1,11 @@ +#ifndef _ASM_GENERIC_BITOPS_EXT2_ATOMIC_SETBIT_H_ +#define _ASM_GENERIC_BITOPS_EXT2_ATOMIC_SETBIT_H_ + +/* + * Atomic bitops based version of ext2 atomic bitops + */ + +#define ext2_set_bit_atomic(l, nr, addr) test_and_set_bit_le(nr, addr) +#define ext2_clear_bit_atomic(l, nr, addr) test_and_clear_bit_le(nr, addr) + +#endif /* _ASM_GENERIC_BITOPS_EXT2_ATOMIC_SETBIT_H_ */ diff --git a/include/asm-generic/bitops/ext2-atomic.h b/include/asm-generic/bitops/ext2-atomic.h new file mode 100644 index 000000000..87f0f109d --- /dev/null +++ b/include/asm-generic/bitops/ext2-atomic.h @@ -0,0 +1,26 @@ +#ifndef _ASM_GENERIC_BITOPS_EXT2_ATOMIC_H_ +#define _ASM_GENERIC_BITOPS_EXT2_ATOMIC_H_ + +/* + * Spinlock based version of ext2 atomic bitops + */ + +#define ext2_set_bit_atomic(lock, nr, addr) \ + ({ \ + int ret; \ + spin_lock(lock); \ + ret = __test_and_set_bit_le(nr, addr); \ + spin_unlock(lock); \ + ret; \ + }) + +#define ext2_clear_bit_atomic(lock, nr, addr) \ + ({ \ + int ret; \ + spin_lock(lock); \ + ret = __test_and_clear_bit_le(nr, addr); \ + spin_unlock(lock); \ + ret; \ + }) + +#endif /* _ASM_GENERIC_BITOPS_EXT2_ATOMIC_H_ */ diff --git a/include/asm-generic/bitops/ffs.h b/include/asm-generic/bitops/ffs.h new file mode 100644 index 000000000..fbbb43af7 --- /dev/null +++ b/include/asm-generic/bitops/ffs.h @@ -0,0 +1,41 @@ +#ifndef _ASM_GENERIC_BITOPS_FFS_H_ +#define _ASM_GENERIC_BITOPS_FFS_H_ + +/** + * ffs - find first bit set + * @x: the word to search + * + * This is defined the same way as + * the libc and compiler builtin ffs routines, therefore + * differs in spirit from the above ffz (man ffs). + */ +static inline int ffs(int x) +{ + int r = 1; + + if (!x) + return 0; + if (!(x & 0xffff)) { + x >>= 16; + r += 16; + } + if (!(x & 0xff)) { + x >>= 8; + r += 8; + } + if (!(x & 0xf)) { + x >>= 4; + r += 4; + } + if (!(x & 3)) { + x >>= 2; + r += 2; + } + if (!(x & 1)) { + x >>= 1; + r += 1; + } + return r; +} + +#endif /* _ASM_GENERIC_BITOPS_FFS_H_ */ diff --git a/include/asm-generic/bitops/ffz.h b/include/asm-generic/bitops/ffz.h new file mode 100644 index 000000000..6744bd4cd --- /dev/null +++ b/include/asm-generic/bitops/ffz.h @@ -0,0 +1,12 @@ +#ifndef _ASM_GENERIC_BITOPS_FFZ_H_ +#define _ASM_GENERIC_BITOPS_FFZ_H_ + +/* + * ffz - find first zero in word. + * @word: The word to search + * + * Undefined if no zero exists, so code should check against ~0UL first. + */ +#define ffz(x) __ffs(~(x)) + +#endif /* _ASM_GENERIC_BITOPS_FFZ_H_ */ diff --git a/include/asm-generic/bitops/find.h b/include/asm-generic/bitops/find.h new file mode 100644 index 000000000..998d4d544 --- /dev/null +++ b/include/asm-generic/bitops/find.h @@ -0,0 +1,62 @@ +#ifndef _ASM_GENERIC_BITOPS_FIND_H_ +#define _ASM_GENERIC_BITOPS_FIND_H_ + +#ifndef find_next_bit +/** + * find_next_bit - find the next set bit in a memory region + * @addr: The address to base the search on + * @offset: The bitnumber to start searching at + * @size: The bitmap size in bits + * + * Returns the bit number for the next set bit + * If no bits are set, returns @size. + */ +extern unsigned long find_next_bit(const unsigned long *addr, unsigned long + size, unsigned long offset); +#endif + +#ifndef find_next_zero_bit +/** + * find_next_zero_bit - find the next cleared bit in a memory region + * @addr: The address to base the search on + * @offset: The bitnumber to start searching at + * @size: The bitmap size in bits + * + * Returns the bit number of the next zero bit + * If no bits are zero, returns @size. + */ +extern unsigned long find_next_zero_bit(const unsigned long *addr, unsigned + long size, unsigned long offset); +#endif + +#ifdef CONFIG_GENERIC_FIND_FIRST_BIT + +/** + * find_first_bit - find the first set bit in a memory region + * @addr: The address to start the search at + * @size: The maximum number of bits to search + * + * Returns the bit number of the first set bit. + * If no bits are set, returns @size. + */ +extern unsigned long find_first_bit(const unsigned long *addr, + unsigned long size); + +/** + * find_first_zero_bit - find the first cleared bit in a memory region + * @addr: The address to start the search at + * @size: The maximum number of bits to search + * + * Returns the bit number of the first cleared bit. + * If no bits are zero, returns @size. + */ +extern unsigned long find_first_zero_bit(const unsigned long *addr, + unsigned long size); +#else /* CONFIG_GENERIC_FIND_FIRST_BIT */ + +#define find_first_bit(addr, size) find_next_bit((addr), (size), 0) +#define find_first_zero_bit(addr, size) find_next_zero_bit((addr), (size), 0) + +#endif /* CONFIG_GENERIC_FIND_FIRST_BIT */ + +#endif /*_ASM_GENERIC_BITOPS_FIND_H_ */ diff --git a/include/asm-generic/bitops/fls.h b/include/asm-generic/bitops/fls.h new file mode 100644 index 000000000..0576d1f42 --- /dev/null +++ b/include/asm-generic/bitops/fls.h @@ -0,0 +1,41 @@ +#ifndef _ASM_GENERIC_BITOPS_FLS_H_ +#define _ASM_GENERIC_BITOPS_FLS_H_ + +/** + * fls - find last (most-significant) bit set + * @x: the word to search + * + * This is defined the same way as ffs. + * Note fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32. + */ + +static __always_inline int fls(int x) +{ + int r = 32; + + if (!x) + return 0; + if (!(x & 0xffff0000u)) { + x <<= 16; + r -= 16; + } + if (!(x & 0xff000000u)) { + x <<= 8; + r -= 8; + } + if (!(x & 0xf0000000u)) { + x <<= 4; + r -= 4; + } + if (!(x & 0xc0000000u)) { + x <<= 2; + r -= 2; + } + if (!(x & 0x80000000u)) { + x <<= 1; + r -= 1; + } + return r; +} + +#endif /* _ASM_GENERIC_BITOPS_FLS_H_ */ diff --git a/include/asm-generic/bitops/fls64.h b/include/asm-generic/bitops/fls64.h new file mode 100644 index 000000000..b097cf844 --- /dev/null +++ b/include/asm-generic/bitops/fls64.h @@ -0,0 +1,36 @@ +#ifndef _ASM_GENERIC_BITOPS_FLS64_H_ +#define _ASM_GENERIC_BITOPS_FLS64_H_ + +#include <asm/types.h> + +/** + * 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 __always_inline int fls64(__u64 x) +{ + __u32 h = x >> 32; + if (h) + return fls(h) + 32; + return fls(x); +} +#elif BITS_PER_LONG == 64 +static __always_inline int fls64(__u64 x) +{ + if (x == 0) + return 0; + return __fls(x) + 1; +} +#else +#error BITS_PER_LONG not 32 or 64 +#endif + +#endif /* _ASM_GENERIC_BITOPS_FLS64_H_ */ diff --git a/include/asm-generic/bitops/hweight.h b/include/asm-generic/bitops/hweight.h new file mode 100644 index 000000000..a94d6519c --- /dev/null +++ b/include/asm-generic/bitops/hweight.h @@ -0,0 +1,7 @@ +#ifndef _ASM_GENERIC_BITOPS_HWEIGHT_H_ +#define _ASM_GENERIC_BITOPS_HWEIGHT_H_ + +#include <asm-generic/bitops/arch_hweight.h> +#include <asm-generic/bitops/const_hweight.h> + +#endif /* _ASM_GENERIC_BITOPS_HWEIGHT_H_ */ diff --git a/include/asm-generic/bitops/le.h b/include/asm-generic/bitops/le.h new file mode 100644 index 000000000..61731543c --- /dev/null +++ b/include/asm-generic/bitops/le.h @@ -0,0 +1,97 @@ +#ifndef _ASM_GENERIC_BITOPS_LE_H_ +#define _ASM_GENERIC_BITOPS_LE_H_ + +#include <asm/types.h> +#include <asm/byteorder.h> + +#if defined(__LITTLE_ENDIAN) + +#define BITOP_LE_SWIZZLE 0 + +static inline unsigned long find_next_zero_bit_le(const void *addr, + unsigned long size, unsigned long offset) +{ + return find_next_zero_bit(addr, size, offset); +} + +static inline unsigned long find_next_bit_le(const void *addr, + unsigned long size, unsigned long offset) +{ + return find_next_bit(addr, size, offset); +} + +static inline unsigned long find_first_zero_bit_le(const void *addr, + unsigned long size) +{ + return find_first_zero_bit(addr, size); +} + +#elif defined(__BIG_ENDIAN) + +#define BITOP_LE_SWIZZLE ((BITS_PER_LONG-1) & ~0x7) + +#ifndef find_next_zero_bit_le +extern unsigned long find_next_zero_bit_le(const void *addr, + unsigned long size, unsigned long offset); +#endif + +#ifndef find_next_bit_le +extern unsigned long find_next_bit_le(const void *addr, + unsigned long size, unsigned long offset); +#endif + +#ifndef find_first_zero_bit_le +#define find_first_zero_bit_le(addr, size) \ + find_next_zero_bit_le((addr), (size), 0) +#endif + +#else +#error "Please fix <asm/byteorder.h>" +#endif + +static inline int test_bit_le(int nr, const void *addr) +{ + return test_bit(nr ^ BITOP_LE_SWIZZLE, addr); +} + +static inline void set_bit_le(int nr, void *addr) +{ + set_bit(nr ^ BITOP_LE_SWIZZLE, addr); +} + +static inline void clear_bit_le(int nr, void *addr) +{ + clear_bit(nr ^ BITOP_LE_SWIZZLE, addr); +} + +static inline void __set_bit_le(int nr, void *addr) +{ + __set_bit(nr ^ BITOP_LE_SWIZZLE, addr); +} + +static inline void __clear_bit_le(int nr, void *addr) +{ + __clear_bit(nr ^ BITOP_LE_SWIZZLE, addr); +} + +static inline int test_and_set_bit_le(int nr, void *addr) +{ + return test_and_set_bit(nr ^ BITOP_LE_SWIZZLE, addr); +} + +static inline int test_and_clear_bit_le(int nr, void *addr) +{ + return test_and_clear_bit(nr ^ BITOP_LE_SWIZZLE, addr); +} + +static inline int __test_and_set_bit_le(int nr, void *addr) +{ + return __test_and_set_bit(nr ^ BITOP_LE_SWIZZLE, addr); +} + +static inline int __test_and_clear_bit_le(int nr, void *addr) +{ + return __test_and_clear_bit(nr ^ BITOP_LE_SWIZZLE, addr); +} + +#endif /* _ASM_GENERIC_BITOPS_LE_H_ */ diff --git a/include/asm-generic/bitops/lock.h b/include/asm-generic/bitops/lock.h new file mode 100644 index 000000000..c30266e94 --- /dev/null +++ b/include/asm-generic/bitops/lock.h @@ -0,0 +1,45 @@ +#ifndef _ASM_GENERIC_BITOPS_LOCK_H_ +#define _ASM_GENERIC_BITOPS_LOCK_H_ + +/** + * test_and_set_bit_lock - Set a bit and return its old value, for lock + * @nr: Bit to set + * @addr: Address to count from + * + * This operation is atomic and provides acquire barrier semantics. + * It can be used to implement bit locks. + */ +#define test_and_set_bit_lock(nr, addr) test_and_set_bit(nr, addr) + +/** + * clear_bit_unlock - Clear a bit in memory, for unlock + * @nr: the bit to set + * @addr: the address to start counting from + * + * This operation is atomic and provides release barrier semantics. + */ +#define clear_bit_unlock(nr, addr) \ +do { \ + smp_mb__before_atomic(); \ + clear_bit(nr, addr); \ +} while (0) + +/** + * __clear_bit_unlock - Clear a bit in memory, for unlock + * @nr: the bit to set + * @addr: the address to start counting from + * + * This operation is like clear_bit_unlock, however it is not atomic. + * It does provide release barrier semantics so it can be used to unlock + * a bit lock, however it would only be used if no other CPU can modify + * any bits in the memory until the lock is released (a good example is + * if the bit lock itself protects access to the other bits in the word). + */ +#define __clear_bit_unlock(nr, addr) \ +do { \ + smp_mb(); \ + __clear_bit(nr, addr); \ +} while (0) + +#endif /* _ASM_GENERIC_BITOPS_LOCK_H_ */ + diff --git a/include/asm-generic/bitops/non-atomic.h b/include/asm-generic/bitops/non-atomic.h new file mode 100644 index 000000000..697cc2b7e --- /dev/null +++ b/include/asm-generic/bitops/non-atomic.h @@ -0,0 +1,108 @@ +#ifndef _ASM_GENERIC_BITOPS_NON_ATOMIC_H_ +#define _ASM_GENERIC_BITOPS_NON_ATOMIC_H_ + +#include <asm/types.h> + +/** + * __set_bit - Set a bit in memory + * @nr: the bit to set + * @addr: the address to start counting from + * + * Unlike set_bit(), this function is non-atomic and may be reordered. + * If it's called on the same region of memory simultaneously, the effect + * may be that only one operation succeeds. + */ +static inline void __set_bit(int nr, volatile unsigned long *addr) +{ + unsigned long mask = BIT_MASK(nr); + unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr); + + *p |= mask; +} + +static inline void __clear_bit(int nr, volatile unsigned long *addr) +{ + unsigned long mask = BIT_MASK(nr); + unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr); + + *p &= ~mask; +} + +/** + * __change_bit - Toggle a bit in memory + * @nr: the bit to change + * @addr: the address to start counting from + * + * Unlike change_bit(), this function is non-atomic and may be reordered. + * If it's called on the same region of memory simultaneously, the effect + * may be that only one operation succeeds. + */ +static inline void __change_bit(int nr, volatile unsigned long *addr) +{ + unsigned long mask = BIT_MASK(nr); + unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr); + + *p ^= mask; +} + +/** + * __test_and_set_bit - Set a bit and return its old value + * @nr: Bit to set + * @addr: Address to count from + * + * This operation is non-atomic and can be reordered. + * If two examples of this operation race, one can appear to succeed + * but actually fail. You must protect multiple accesses with a lock. + */ +static inline int __test_and_set_bit(int nr, volatile unsigned long *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; +} + +/** + * __test_and_clear_bit - Clear a bit and return its old value + * @nr: Bit to clear + * @addr: Address to count from + * + * This operation is non-atomic and can be reordered. + * If two examples of this operation race, one can appear to succeed + * but actually fail. You must protect multiple accesses with a lock. + */ +static inline int __test_and_clear_bit(int nr, volatile unsigned long *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; +} + +/* WARNING: non atomic and it can be reordered! */ +static inline int __test_and_change_bit(int nr, + volatile unsigned long *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; +} + +/** + * test_bit - Determine whether a bit is set + * @nr: bit number to test + * @addr: Address to start counting from + */ +static inline int test_bit(int nr, const volatile unsigned long *addr) +{ + return 1UL & (addr[BIT_WORD(nr)] >> (nr & (BITS_PER_LONG-1))); +} + +#endif /* _ASM_GENERIC_BITOPS_NON_ATOMIC_H_ */ diff --git a/include/asm-generic/bitops/sched.h b/include/asm-generic/bitops/sched.h new file mode 100644 index 000000000..604fab703 --- /dev/null +++ b/include/asm-generic/bitops/sched.h @@ -0,0 +1,31 @@ +#ifndef _ASM_GENERIC_BITOPS_SCHED_H_ +#define _ASM_GENERIC_BITOPS_SCHED_H_ + +#include <linux/compiler.h> /* unlikely() */ +#include <asm/types.h> + +/* + * Every architecture must define this function. It's the fastest + * way of searching a 100-bit bitmap. It's guaranteed that at least + * one of the 100 bits is cleared. + */ +static inline int sched_find_first_bit(const unsigned long *b) +{ +#if BITS_PER_LONG == 64 + if (b[0]) + return __ffs(b[0]); + return __ffs(b[1]) + 64; +#elif BITS_PER_LONG == 32 + if (b[0]) + return __ffs(b[0]); + if (b[1]) + return __ffs(b[1]) + 32; + if (b[2]) + return __ffs(b[2]) + 64; + return __ffs(b[3]) + 96; +#else +#error BITS_PER_LONG not defined +#endif +} + +#endif /* _ASM_GENERIC_BITOPS_SCHED_H_ */ |