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	 bc9d6635c2
			
		
	
	
		bc9d6635c2
		
	
	
	
	
		
			
			for_each_bit() macros depend on find_bit() machinery, and so the proper place for them is the find.h header. Signed-off-by: Yury Norov <yury.norov@gmail.com> Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
		
			
				
	
	
		
			306 lines
		
	
	
	
		
			7.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			306 lines
		
	
	
	
		
			7.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* SPDX-License-Identifier: GPL-2.0 */
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| #ifndef _LINUX_BITOPS_H
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| #define _LINUX_BITOPS_H
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| 
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| #include <asm/types.h>
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| #include <linux/bits.h>
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| #include <linux/typecheck.h>
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| 
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| #include <uapi/linux/kernel.h>
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| 
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| /* Set bits in the first 'n' bytes when loaded from memory */
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| #ifdef __LITTLE_ENDIAN
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| #  define aligned_byte_mask(n) ((1UL << 8*(n))-1)
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| #else
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| #  define aligned_byte_mask(n) (~0xffUL << (BITS_PER_LONG - 8 - 8*(n)))
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| #endif
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| 
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| #define BITS_PER_TYPE(type)	(sizeof(type) * BITS_PER_BYTE)
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| #define BITS_TO_LONGS(nr)	__KERNEL_DIV_ROUND_UP(nr, BITS_PER_TYPE(long))
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| #define BITS_TO_U64(nr)		__KERNEL_DIV_ROUND_UP(nr, BITS_PER_TYPE(u64))
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| #define BITS_TO_U32(nr)		__KERNEL_DIV_ROUND_UP(nr, BITS_PER_TYPE(u32))
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| #define BITS_TO_BYTES(nr)	__KERNEL_DIV_ROUND_UP(nr, BITS_PER_TYPE(char))
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| 
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| extern unsigned int __sw_hweight8(unsigned int w);
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| extern unsigned int __sw_hweight16(unsigned int w);
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| extern unsigned int __sw_hweight32(unsigned int w);
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| extern unsigned long __sw_hweight64(__u64 w);
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| 
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| /*
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|  * Include this here because some architectures need generic_ffs/fls in
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|  * scope
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|  */
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| #include <asm/bitops.h>
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| 
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| static inline int get_bitmask_order(unsigned int count)
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| {
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| 	int order;
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| 
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| 	order = fls(count);
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| 	return order;	/* We could be slightly more clever with -1 here... */
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| }
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| 
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| static __always_inline unsigned long hweight_long(unsigned long w)
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| {
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| 	return sizeof(w) == 4 ? hweight32(w) : hweight64((__u64)w);
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| }
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| 
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| /**
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|  * rol64 - rotate a 64-bit value left
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|  * @word: value to rotate
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|  * @shift: bits to roll
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|  */
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| static inline __u64 rol64(__u64 word, unsigned int shift)
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| {
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| 	return (word << (shift & 63)) | (word >> ((-shift) & 63));
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| }
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| 
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| /**
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|  * ror64 - rotate a 64-bit value right
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|  * @word: value to rotate
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|  * @shift: bits to roll
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|  */
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| static inline __u64 ror64(__u64 word, unsigned int shift)
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| {
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| 	return (word >> (shift & 63)) | (word << ((-shift) & 63));
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| }
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| 
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| /**
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|  * rol32 - rotate a 32-bit value left
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|  * @word: value to rotate
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|  * @shift: bits to roll
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|  */
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| static inline __u32 rol32(__u32 word, unsigned int shift)
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| {
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| 	return (word << (shift & 31)) | (word >> ((-shift) & 31));
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| }
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| 
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| /**
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|  * ror32 - rotate a 32-bit value right
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|  * @word: value to rotate
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|  * @shift: bits to roll
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|  */
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| static inline __u32 ror32(__u32 word, unsigned int shift)
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| {
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| 	return (word >> (shift & 31)) | (word << ((-shift) & 31));
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| }
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| 
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| /**
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|  * rol16 - rotate a 16-bit value left
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|  * @word: value to rotate
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|  * @shift: bits to roll
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|  */
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| static inline __u16 rol16(__u16 word, unsigned int shift)
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| {
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| 	return (word << (shift & 15)) | (word >> ((-shift) & 15));
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| }
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| 
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| /**
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|  * ror16 - rotate a 16-bit value right
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|  * @word: value to rotate
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|  * @shift: bits to roll
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|  */
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| static inline __u16 ror16(__u16 word, unsigned int shift)
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| {
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| 	return (word >> (shift & 15)) | (word << ((-shift) & 15));
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| }
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| 
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| /**
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|  * rol8 - rotate an 8-bit value left
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|  * @word: value to rotate
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|  * @shift: bits to roll
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|  */
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| static inline __u8 rol8(__u8 word, unsigned int shift)
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| {
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| 	return (word << (shift & 7)) | (word >> ((-shift) & 7));
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| }
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| 
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| /**
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|  * ror8 - rotate an 8-bit value right
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|  * @word: value to rotate
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|  * @shift: bits to roll
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|  */
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| static inline __u8 ror8(__u8 word, unsigned int shift)
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| {
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| 	return (word >> (shift & 7)) | (word << ((-shift) & 7));
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| }
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| 
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| /**
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|  * sign_extend32 - sign extend a 32-bit value using specified bit as sign-bit
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|  * @value: value to sign extend
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|  * @index: 0 based bit index (0<=index<32) to sign bit
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|  *
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|  * This is safe to use for 16- and 8-bit types as well.
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|  */
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| static __always_inline __s32 sign_extend32(__u32 value, int index)
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| {
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| 	__u8 shift = 31 - index;
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| 	return (__s32)(value << shift) >> shift;
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| }
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| 
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| /**
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|  * sign_extend64 - sign extend a 64-bit value using specified bit as sign-bit
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|  * @value: value to sign extend
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|  * @index: 0 based bit index (0<=index<64) to sign bit
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|  */
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| static __always_inline __s64 sign_extend64(__u64 value, int index)
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| {
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| 	__u8 shift = 63 - index;
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| 	return (__s64)(value << shift) >> shift;
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| }
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| 
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| static inline unsigned fls_long(unsigned long l)
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| {
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| 	if (sizeof(l) == 4)
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| 		return fls(l);
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| 	return fls64(l);
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| }
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| 
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| static inline int get_count_order(unsigned int count)
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| {
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| 	if (count == 0)
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| 		return -1;
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| 
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| 	return fls(--count);
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| }
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| 
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| /**
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|  * get_count_order_long - get order after rounding @l up to power of 2
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|  * @l: parameter
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|  *
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|  * it is same as get_count_order() but with long type parameter
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|  */
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| static inline int get_count_order_long(unsigned long l)
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| {
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| 	if (l == 0UL)
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| 		return -1;
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| 	return (int)fls_long(--l);
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| }
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| 
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| /**
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|  * __ffs64 - find first set bit in a 64 bit word
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|  * @word: The 64 bit word
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|  *
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|  * On 64 bit arches this is a synonym for __ffs
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|  * The result is not defined if no bits are set, so check that @word
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|  * is non-zero before calling this.
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|  */
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| static inline unsigned long __ffs64(u64 word)
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| {
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| #if BITS_PER_LONG == 32
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| 	if (((u32)word) == 0UL)
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| 		return __ffs((u32)(word >> 32)) + 32;
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| #elif BITS_PER_LONG != 64
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| #error BITS_PER_LONG not 32 or 64
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| #endif
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| 	return __ffs((unsigned long)word);
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| }
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| 
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| /**
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|  * assign_bit - Assign value to a bit in memory
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|  * @nr: the bit to set
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|  * @addr: the address to start counting from
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|  * @value: the value to assign
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|  */
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| static __always_inline void assign_bit(long nr, volatile unsigned long *addr,
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| 				       bool value)
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| {
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| 	if (value)
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| 		set_bit(nr, addr);
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| 	else
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| 		clear_bit(nr, addr);
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| }
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| 
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| static __always_inline void __assign_bit(long nr, volatile unsigned long *addr,
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| 					 bool value)
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| {
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| 	if (value)
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| 		__set_bit(nr, addr);
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| 	else
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| 		__clear_bit(nr, addr);
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| }
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| 
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| /**
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|  * __ptr_set_bit - Set bit in a pointer's value
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|  * @nr: the bit to set
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|  * @addr: the address of the pointer variable
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|  *
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|  * Example:
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|  *	void *p = foo();
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|  *	__ptr_set_bit(bit, &p);
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|  */
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| #define __ptr_set_bit(nr, addr)                         \
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| 	({                                              \
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| 		typecheck_pointer(*(addr));             \
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| 		__set_bit(nr, (unsigned long *)(addr)); \
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| 	})
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| 
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| /**
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|  * __ptr_clear_bit - Clear bit in a pointer's value
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|  * @nr: the bit to clear
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|  * @addr: the address of the pointer variable
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|  *
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|  * Example:
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|  *	void *p = foo();
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|  *	__ptr_clear_bit(bit, &p);
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|  */
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| #define __ptr_clear_bit(nr, addr)                         \
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| 	({                                                \
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| 		typecheck_pointer(*(addr));               \
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| 		__clear_bit(nr, (unsigned long *)(addr)); \
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| 	})
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| 
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| /**
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|  * __ptr_test_bit - Test bit in a pointer's value
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|  * @nr: the bit to test
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|  * @addr: the address of the pointer variable
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|  *
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|  * Example:
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|  *	void *p = foo();
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|  *	if (__ptr_test_bit(bit, &p)) {
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|  *	        ...
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|  *	} else {
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|  *		...
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|  *	}
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|  */
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| #define __ptr_test_bit(nr, addr)                       \
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| 	({                                             \
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| 		typecheck_pointer(*(addr));            \
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| 		test_bit(nr, (unsigned long *)(addr)); \
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| 	})
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| 
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| #ifdef __KERNEL__
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| 
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| #ifndef set_mask_bits
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| #define set_mask_bits(ptr, mask, bits)	\
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| ({								\
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| 	const typeof(*(ptr)) mask__ = (mask), bits__ = (bits);	\
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| 	typeof(*(ptr)) old__, new__;				\
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| 								\
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| 	do {							\
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| 		old__ = READ_ONCE(*(ptr));			\
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| 		new__ = (old__ & ~mask__) | bits__;		\
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| 	} while (cmpxchg(ptr, old__, new__) != old__);		\
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| 								\
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| 	old__;							\
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| })
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| #endif
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| 
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| #ifndef bit_clear_unless
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| #define bit_clear_unless(ptr, clear, test)	\
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| ({								\
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| 	const typeof(*(ptr)) clear__ = (clear), test__ = (test);\
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| 	typeof(*(ptr)) old__, new__;				\
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| 								\
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| 	do {							\
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| 		old__ = READ_ONCE(*(ptr));			\
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| 		new__ = old__ & ~clear__;			\
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| 	} while (!(old__ & test__) &&				\
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| 		 cmpxchg(ptr, old__, new__) != old__);		\
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| 								\
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| 	!(old__ & test__);					\
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| })
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| #endif
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| 
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| #endif /* __KERNEL__ */
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| #endif
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