kernel: add common infrastructure for unaligned access
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>
2008-04-29 12:03:27 +04:00
|
|
|
#ifndef _LINUX_UNALIGNED_PACKED_STRUCT_H
|
|
|
|
#define _LINUX_UNALIGNED_PACKED_STRUCT_H
|
|
|
|
|
2022-01-20 05:08:12 +03:00
|
|
|
#include <linux/types.h>
|
kernel: add common infrastructure for unaligned access
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>
2008-04-29 12:03:27 +04:00
|
|
|
|
2011-01-13 03:59:37 +03:00
|
|
|
struct __una_u16 { u16 x; } __packed;
|
|
|
|
struct __una_u32 { u32 x; } __packed;
|
|
|
|
struct __una_u64 { u64 x; } __packed;
|
kernel: add common infrastructure for unaligned access
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>
2008-04-29 12:03:27 +04:00
|
|
|
|
|
|
|
static inline u16 __get_unaligned_cpu16(const void *p)
|
|
|
|
{
|
|
|
|
const struct __una_u16 *ptr = (const struct __una_u16 *)p;
|
|
|
|
return ptr->x;
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline u32 __get_unaligned_cpu32(const void *p)
|
|
|
|
{
|
|
|
|
const struct __una_u32 *ptr = (const struct __una_u32 *)p;
|
|
|
|
return ptr->x;
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline u64 __get_unaligned_cpu64(const void *p)
|
|
|
|
{
|
|
|
|
const struct __una_u64 *ptr = (const struct __una_u64 *)p;
|
|
|
|
return ptr->x;
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline void __put_unaligned_cpu16(u16 val, void *p)
|
|
|
|
{
|
|
|
|
struct __una_u16 *ptr = (struct __una_u16 *)p;
|
|
|
|
ptr->x = val;
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline void __put_unaligned_cpu32(u32 val, void *p)
|
|
|
|
{
|
|
|
|
struct __una_u32 *ptr = (struct __una_u32 *)p;
|
|
|
|
ptr->x = val;
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline void __put_unaligned_cpu64(u64 val, void *p)
|
|
|
|
{
|
|
|
|
struct __una_u64 *ptr = (struct __una_u64 *)p;
|
|
|
|
ptr->x = val;
|
|
|
|
}
|
|
|
|
|
|
|
|
#endif /* _LINUX_UNALIGNED_PACKED_STRUCT_H */
|