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		064106a91b
		
	
	
	
	
		
			
			Create a linux/unaligned directory similar in spirit to the linux/byteorder
folder to hold generic implementations collected from various arches.
Currently there are five implementations:
1) packed_struct.h: C-struct based, from asm-generic/unaligned.h
2) le_byteshift.h: Open coded byte-swapping, heavily based on asm-arm
3) be_byteshift.h: Open coded byte-swapping, heavily based on asm-arm
4) memmove.h: taken from multiple implementations in tree
5) access_ok.h: taken from x86 and others, unaligned access is ok.
All of the new implementations checks for sizes not equal to 1,2,4,8
and will fail to link.
API additions:
get_unaligned_{le16|le32|le64|be16|be32|be64}(p) which is meant to replace
code of the form:
le16_to_cpu(get_unaligned((__le16 *)p));
put_unaligned_{le16|le32|le64|be16|be32|be64}(val, pointer) which is meant to
replace code of the form:
put_unaligned(cpu_to_le16(val), (__le16 *)p);
The headers that arches should include from their asm/unaligned.h:
access_ok.h : Wrappers of the byteswapping functions in asm/byteorder
Choose a particular implementation for little-endian access:
le_byteshift.h
le_memmove.h (arch must be LE)
le_struct.h (arch must be LE)
Choose a particular implementation for big-endian access:
be_byteshift.h
be_memmove.h (arch must be BE)
be_struct.h (arch must be BE)
After including as needed from the above, include unaligned/generic.h and
define your arch's get/put_unaligned as (for LE):
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
		
	
			
		
			
				
	
	
		
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			68 lines
		
	
	
		
			1.3 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| #ifndef _LINUX_UNALIGNED_ACCESS_OK_H
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| #define _LINUX_UNALIGNED_ACCESS_OK_H
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| 
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| #include <linux/kernel.h>
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| #include <asm/byteorder.h>
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| 
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| static inline u16 get_unaligned_le16(const void *p)
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| {
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| 	return le16_to_cpup((__le16 *)p);
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| }
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| 
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| static inline u32 get_unaligned_le32(const void *p)
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| {
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| 	return le32_to_cpup((__le32 *)p);
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| }
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| 
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| static inline u64 get_unaligned_le64(const void *p)
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| {
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| 	return le64_to_cpup((__le64 *)p);
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| }
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| 
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| static inline u16 get_unaligned_be16(const void *p)
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| {
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| 	return be16_to_cpup((__be16 *)p);
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| }
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| 
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| static inline u32 get_unaligned_be32(const void *p)
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| {
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| 	return be32_to_cpup((__be32 *)p);
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| }
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| 
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| static inline u64 get_unaligned_be64(const void *p)
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| {
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| 	return be64_to_cpup((__be64 *)p);
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| }
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| 
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| static inline void put_unaligned_le16(u16 val, void *p)
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| {
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| 	*((__le16 *)p) = cpu_to_le16(val);
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| }
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| 
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| static inline void put_unaligned_le32(u32 val, void *p)
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| {
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| 	*((__le32 *)p) = cpu_to_le32(val);
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| }
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| 
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| static inline void put_unaligned_le64(u64 val, void *p)
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| {
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| 	*((__le64 *)p) = cpu_to_le64(val);
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| }
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| 
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| static inline void put_unaligned_be16(u16 val, void *p)
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| {
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| 	*((__be16 *)p) = cpu_to_be16(val);
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| }
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| 
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| static inline void put_unaligned_be32(u32 val, void *p)
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| {
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| 	*((__be32 *)p) = cpu_to_be32(val);
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| }
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| 
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| static inline void put_unaligned_be64(u64 val, void *p)
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| {
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| 	*((__be64 *)p) = cpu_to_be64(val);
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| }
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| 
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| #endif /* _LINUX_UNALIGNED_ACCESS_OK_H */
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