From 803f4e1eab7a8938ba3a3c30dd4eb5e9eeef5e63 Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Sat, 8 May 2021 00:07:57 +0200 Subject: [PATCH] asm-generic: simplify asm/unaligned.h The get_unaligned()/put_unaligned() implementations are much more complex than necessary, now that all architectures use the same code. Move everything into one file and use a much more compact way to express the same logic. I've compared the binary output using gcc-11 across defconfig builds for all architectures and found this patch to make no difference, except for a single function on powerpc that needs two additional register moves because of random differences in register allocation. There are a handful of callers of the low-level __get_unaligned_cpu32, so leave that in place for the time being even though the common code no longer uses it. This adds a warning for any caller of get_unaligned()/put_unaligned() that passes in a single-byte pointer, but I've sent patches for all instances that show up in x86 and randconfig builds. It would be nice to change the arguments of the endian-specific accessors to take the matching __be16/__be32/__be64/__le16/__le32/__le64 arguments instead of a void pointer, but that requires more changes to the rest of the kernel. This new version does allow aggregate types into get_unaligned(), which was not the original goal but might come in handy. Signed-off-by: Arnd Bergmann --- include/asm-generic/unaligned.h | 130 ++++++++++++++++++++++++++++++++---- include/linux/unaligned/be_struct.h | 67 ------------------- include/linux/unaligned/generic.h | 115 ------------------------------- include/linux/unaligned/le_struct.h | 67 ------------------- 4 files changed, 117 insertions(+), 262 deletions(-) delete mode 100644 include/linux/unaligned/be_struct.h delete mode 100644 include/linux/unaligned/generic.h delete mode 100644 include/linux/unaligned/le_struct.h diff --git a/include/asm-generic/unaligned.h b/include/asm-generic/unaligned.h index 36bf03a..1c424241 100644 --- a/include/asm-generic/unaligned.h +++ b/include/asm-generic/unaligned.h @@ -6,20 +6,124 @@ * This is the most generic implementation of unaligned accesses * and should work almost anywhere. */ +#include #include -#if defined(__LITTLE_ENDIAN) -# include -# include -# define get_unaligned __get_unaligned_le -# define put_unaligned __put_unaligned_le -#elif defined(__BIG_ENDIAN) -# include -# include -# define get_unaligned __get_unaligned_be -# define put_unaligned __put_unaligned_be -#else -# error need to define endianess -#endif +#define __get_unaligned_t(type, ptr) ({ \ + const struct { type x; } __packed *__pptr = (typeof(__pptr))(ptr); \ + __pptr->x; \ +}) + +#define __put_unaligned_t(type, val, ptr) do { \ + struct { type x; } __packed *__pptr = (typeof(__pptr))(ptr); \ + __pptr->x = (val); \ +} while (0) + +#define get_unaligned(ptr) __get_unaligned_t(typeof(*(ptr)), (ptr)) +#define put_unaligned(val, ptr) __put_unaligned_t(typeof(*(ptr)), (val), (ptr)) + +static inline u16 get_unaligned_le16(const void *p) +{ + return le16_to_cpu(__get_unaligned_t(__le16, p)); +} + +static inline u32 get_unaligned_le32(const void *p) +{ + return le32_to_cpu(__get_unaligned_t(__le32, p)); +} + +static inline u64 get_unaligned_le64(const void *p) +{ + return le64_to_cpu(__get_unaligned_t(__le64, p)); +} + +static inline void put_unaligned_le16(u16 val, void *p) +{ + __put_unaligned_t(__le16, cpu_to_le16(val), p); +} + +static inline void put_unaligned_le32(u32 val, void *p) +{ + __put_unaligned_t(__le32, cpu_to_le32(val), p); +} + +static inline void put_unaligned_le64(u64 val, void *p) +{ + __put_unaligned_t(__le64, cpu_to_le64(val), p); +} + +static inline u16 get_unaligned_be16(const void *p) +{ + return be16_to_cpu(__get_unaligned_t(__be16, p)); +} + +static inline u32 get_unaligned_be32(const void *p) +{ + return be32_to_cpu(__get_unaligned_t(__be32, p)); +} + +static inline u64 get_unaligned_be64(const void *p) +{ + return be64_to_cpu(__get_unaligned_t(__be64, p)); +} + +static inline void put_unaligned_be16(u16 val, void *p) +{ + __put_unaligned_t(__be16, cpu_to_be16(val), p); +} + +static inline void put_unaligned_be32(u32 val, void *p) +{ + __put_unaligned_t(__be32, cpu_to_be32(val), p); +} + +static inline void put_unaligned_be64(u64 val, void *p) +{ + __put_unaligned_t(__be64, cpu_to_be64(val), p); +} + +static inline u32 __get_unaligned_be24(const u8 *p) +{ + return p[0] << 16 | p[1] << 8 | p[2]; +} + +static inline u32 get_unaligned_be24(const void *p) +{ + return __get_unaligned_be24(p); +} + +static inline u32 __get_unaligned_le24(const u8 *p) +{ + return p[0] | p[1] << 8 | p[2] << 16; +} + +static inline u32 get_unaligned_le24(const void *p) +{ + return __get_unaligned_le24(p); +} + +static inline void __put_unaligned_be24(const u32 val, u8 *p) +{ + *p++ = val >> 16; + *p++ = val >> 8; + *p++ = val; +} + +static inline void put_unaligned_be24(const u32 val, void *p) +{ + __put_unaligned_be24(val, p); +} + +static inline void __put_unaligned_le24(const u32 val, u8 *p) +{ + *p++ = val; + *p++ = val >> 8; + *p++ = val >> 16; +} + +static inline void put_unaligned_le24(const u32 val, void *p) +{ + __put_unaligned_le24(val, p); +} #endif /* __ASM_GENERIC_UNALIGNED_H */ diff --git a/include/linux/unaligned/be_struct.h b/include/linux/unaligned/be_struct.h deleted file mode 100644 index 76d9fe2..0000000 --- a/include/linux/unaligned/be_struct.h +++ /dev/null @@ -1,67 +0,0 @@ -/* SPDX-License-Identifier: GPL-2.0 */ -#ifndef _LINUX_UNALIGNED_BE_STRUCT_H -#define _LINUX_UNALIGNED_BE_STRUCT_H - -#include - -static inline u16 get_unaligned_be16(const void *p) -{ - return __get_unaligned_cpu16((const u8 *)p); -} - -static inline u32 get_unaligned_be32(const void *p) -{ - return __get_unaligned_cpu32((const u8 *)p); -} - -static inline u64 get_unaligned_be64(const void *p) -{ - return __get_unaligned_cpu64((const u8 *)p); -} - -static inline void put_unaligned_be16(u16 val, void *p) -{ - __put_unaligned_cpu16(val, p); -} - -static inline void put_unaligned_be32(u32 val, void *p) -{ - __put_unaligned_cpu32(val, p); -} - -static inline void put_unaligned_be64(u64 val, void *p) -{ - __put_unaligned_cpu64(val, p); -} - -static inline u16 get_unaligned_le16(const void *p) -{ - return swab16(__get_unaligned_cpu16((const u8 *)p)); -} - -static inline u32 get_unaligned_le32(const void *p) -{ - return swab32(__get_unaligned_cpu32((const u8 *)p)); -} - -static inline u64 get_unaligned_le64(const void *p) -{ - return swab64(__get_unaligned_cpu64((const u8 *)p)); -} - -static inline void put_unaligned_le16(u16 val, void *p) -{ - __put_unaligned_cpu16(swab16(val), p); -} - -static inline void put_unaligned_le32(u32 val, void *p) -{ - __put_unaligned_cpu32(swab32(val), p); -} - -static inline void put_unaligned_le64(u64 val, void *p) -{ - __put_unaligned_cpu64(swab64(val), p); -} - -#endif /* _LINUX_UNALIGNED_BE_STRUCT_H */ diff --git a/include/linux/unaligned/generic.h b/include/linux/unaligned/generic.h deleted file mode 100644 index 30328949..0000000 --- a/include/linux/unaligned/generic.h +++ /dev/null @@ -1,115 +0,0 @@ -/* SPDX-License-Identifier: GPL-2.0 */ -#ifndef _LINUX_UNALIGNED_GENERIC_H -#define _LINUX_UNALIGNED_GENERIC_H - -#include - -/* - * Cause a link-time error if we try an unaligned access other than - * 1,2,4 or 8 bytes long - */ -extern void __bad_unaligned_access_size(void); - -#define __get_unaligned_le(ptr) ((__force typeof(*(ptr)))({ \ - __builtin_choose_expr(sizeof(*(ptr)) == 1, *(ptr), \ - __builtin_choose_expr(sizeof(*(ptr)) == 2, get_unaligned_le16((ptr)), \ - __builtin_choose_expr(sizeof(*(ptr)) == 4, get_unaligned_le32((ptr)), \ - __builtin_choose_expr(sizeof(*(ptr)) == 8, get_unaligned_le64((ptr)), \ - __bad_unaligned_access_size())))); \ - })) - -#define __get_unaligned_be(ptr) ((__force typeof(*(ptr)))({ \ - __builtin_choose_expr(sizeof(*(ptr)) == 1, *(ptr), \ - __builtin_choose_expr(sizeof(*(ptr)) == 2, get_unaligned_be16((ptr)), \ - __builtin_choose_expr(sizeof(*(ptr)) == 4, get_unaligned_be32((ptr)), \ - __builtin_choose_expr(sizeof(*(ptr)) == 8, get_unaligned_be64((ptr)), \ - __bad_unaligned_access_size())))); \ - })) - -#define __put_unaligned_le(val, ptr) ({ \ - void *__gu_p = (ptr); \ - switch (sizeof(*(ptr))) { \ - case 1: \ - *(u8 *)__gu_p = (__force u8)(val); \ - break; \ - case 2: \ - put_unaligned_le16((__force u16)(val), __gu_p); \ - break; \ - case 4: \ - put_unaligned_le32((__force u32)(val), __gu_p); \ - break; \ - case 8: \ - put_unaligned_le64((__force u64)(val), __gu_p); \ - break; \ - default: \ - __bad_unaligned_access_size(); \ - break; \ - } \ - (void)0; }) - -#define __put_unaligned_be(val, ptr) ({ \ - void *__gu_p = (ptr); \ - switch (sizeof(*(ptr))) { \ - case 1: \ - *(u8 *)__gu_p = (__force u8)(val); \ - break; \ - case 2: \ - put_unaligned_be16((__force u16)(val), __gu_p); \ - break; \ - case 4: \ - put_unaligned_be32((__force u32)(val), __gu_p); \ - break; \ - case 8: \ - put_unaligned_be64((__force u64)(val), __gu_p); \ - break; \ - default: \ - __bad_unaligned_access_size(); \ - break; \ - } \ - (void)0; }) - -static inline u32 __get_unaligned_be24(const u8 *p) -{ - return p[0] << 16 | p[1] << 8 | p[2]; -} - -static inline u32 get_unaligned_be24(const void *p) -{ - return __get_unaligned_be24(p); -} - -static inline u32 __get_unaligned_le24(const u8 *p) -{ - return p[0] | p[1] << 8 | p[2] << 16; -} - -static inline u32 get_unaligned_le24(const void *p) -{ - return __get_unaligned_le24(p); -} - -static inline void __put_unaligned_be24(const u32 val, u8 *p) -{ - *p++ = val >> 16; - *p++ = val >> 8; - *p++ = val; -} - -static inline void put_unaligned_be24(const u32 val, void *p) -{ - __put_unaligned_be24(val, p); -} - -static inline void __put_unaligned_le24(const u32 val, u8 *p) -{ - *p++ = val; - *p++ = val >> 8; - *p++ = val >> 16; -} - -static inline void put_unaligned_le24(const u32 val, void *p) -{ - __put_unaligned_le24(val, p); -} - -#endif /* _LINUX_UNALIGNED_GENERIC_H */ diff --git a/include/linux/unaligned/le_struct.h b/include/linux/unaligned/le_struct.h deleted file mode 100644 index 22f90a4..0000000 --- a/include/linux/unaligned/le_struct.h +++ /dev/null @@ -1,67 +0,0 @@ -/* SPDX-License-Identifier: GPL-2.0 */ -#ifndef _LINUX_UNALIGNED_LE_STRUCT_H -#define _LINUX_UNALIGNED_LE_STRUCT_H - -#include - -static inline u16 get_unaligned_le16(const void *p) -{ - return __get_unaligned_cpu16((const u8 *)p); -} - -static inline u32 get_unaligned_le32(const void *p) -{ - return __get_unaligned_cpu32((const u8 *)p); -} - -static inline u64 get_unaligned_le64(const void *p) -{ - return __get_unaligned_cpu64((const u8 *)p); -} - -static inline void put_unaligned_le16(u16 val, void *p) -{ - __put_unaligned_cpu16(val, p); -} - -static inline void put_unaligned_le32(u32 val, void *p) -{ - __put_unaligned_cpu32(val, p); -} - -static inline void put_unaligned_le64(u64 val, void *p) -{ - __put_unaligned_cpu64(val, p); -} - -static inline u16 get_unaligned_be16(const void *p) -{ - return swab16(__get_unaligned_cpu16((const u8 *)p)); -} - -static inline u32 get_unaligned_be32(const void *p) -{ - return swab32(__get_unaligned_cpu32((const u8 *)p)); -} - -static inline u64 get_unaligned_be64(const void *p) -{ - return swab64(__get_unaligned_cpu64((const u8 *)p)); -} - -static inline void put_unaligned_be16(u16 val, void *p) -{ - __put_unaligned_cpu16(swab16(val), p); -} - -static inline void put_unaligned_be32(u32 val, void *p) -{ - __put_unaligned_cpu32(swab32(val), p); -} - -static inline void put_unaligned_be64(u64 val, void *p) -{ - __put_unaligned_cpu64(swab64(val), p); -} - -#endif /* _LINUX_UNALIGNED_LE_STRUCT_H */ -- 2.7.4