arch/csky/include/asm/uaccess.h

File Facts

System

Linux kernel

Corpus path

arch/csky/include/asm/uaccess.h

Extension

.h

Size

4980 bytes

Lines

204

Domain

Architecture Layer

Bucket

arch/csky

Inferred role

Architecture Layer: implementation source

Status

source implementation candidate

Why This File Exists

CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.

• CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.
• Touches user memory; correctness depends on fault-safe copying and privilege boundary handling.

Dependency Surface

• asm-generic/uaccess.h

Detected Declarations

• function __put_user_fn
• function __get_user_fn

Annotated Snippet

#ifndef __ASM_CSKY_UACCESS_H
#define __ASM_CSKY_UACCESS_H

/*
 * __put_user_fn
 */
extern int __put_user_bad(void);

#define __put_user_asm_b(x, ptr, err)			\
do {							\
	int errcode;					\
	__asm__ __volatile__(				\
	"1:     stb   %1, (%2,0)	\n"		\
	"       br    3f		\n"		\
	"2:     mov   %0, %3		\n"		\
	"       br    3f		\n"		\
	".section __ex_table, \"a\"	\n"		\
	".align   2			\n"		\
	".long    1b,2b			\n"		\
	".previous			\n"		\
	"3:				\n"		\
	: "=r"(err), "=r"(x), "=r"(ptr), "=r"(errcode)	\
	: "0"(err), "1"(x), "2"(ptr), "3"(-EFAULT)	\
	: "memory");					\
} while (0)

#define __put_user_asm_h(x, ptr, err)			\
do {							\
	int errcode;					\
	__asm__ __volatile__(				\
	"1:     sth   %1, (%2,0)	\n"		\
	"       br    3f		\n"		\
	"2:     mov   %0, %3		\n"		\
	"       br    3f		\n"		\
	".section __ex_table, \"a\"	\n"		\
	".align   2			\n"		\
	".long    1b,2b			\n"		\
	".previous			\n"		\
	"3:				\n"		\
	: "=r"(err), "=r"(x), "=r"(ptr), "=r"(errcode)	\
	: "0"(err), "1"(x), "2"(ptr), "3"(-EFAULT)	\
	: "memory");					\
} while (0)

#define __put_user_asm_w(x, ptr, err)			\
do {							\
	int errcode;					\
	__asm__ __volatile__(				\
	"1:     stw   %1, (%2,0)	\n"		\
	"       br    3f		\n"		\
	"2:     mov   %0, %3		\n"		\
	"       br    3f		\n"		\
	".section __ex_table,\"a\"	\n"		\
	".align   2			\n"		\
	".long    1b, 2b		\n"		\
	".previous			\n"		\
	"3:				\n"		\
	: "=r"(err), "=r"(x), "=r"(ptr), "=r"(errcode)	\
	: "0"(err), "1"(x), "2"(ptr), "3"(-EFAULT)	\
	: "memory");					\
} while (0)

#define __put_user_asm_64(x, ptr, err)			\
do {							\
	int tmp;					\
	int errcode;					\
							\
	__asm__ __volatile__(				\
	"     ldw     %3, (%1, 0)     \n"		\
	"1:   stw     %3, (%2, 0)     \n"		\
	"     ldw     %3, (%1, 4)     \n"		\
	"2:   stw     %3, (%2, 4)     \n"		\
	"     br      4f              \n"		\
	"3:   mov     %0, %4          \n"		\
	"     br      4f              \n"		\
	".section __ex_table, \"a\"   \n"		\
	".align   2                   \n"		\
	".long    1b, 3b              \n"		\
	".long    2b, 3b              \n"		\
	".previous                    \n"		\
	"4:                           \n"		\
	: "=r"(err), "=r"(x), "=r"(ptr),		\
	  "=r"(tmp), "=r"(errcode)			\
	: "0"(err), "1"(x), "2"(ptr), "3"(0),		\
	  "4"(-EFAULT)					\
	: "memory");					\
} while (0)

static inline int __put_user_fn(size_t size, void __user *ptr, void *x)
{

Annotation

• Immediate include surface: `asm-generic/uaccess.h`.
• Detected declarations: `function __put_user_fn`, `function __get_user_fn`.
• Atlas domain: Architecture Layer / arch/csky.
• Implementation status: source implementation candidate.
• This snippet crosses the user/kernel memory boundary; validate fault handling and access checks before translating the pattern.

Implementation Notes

• This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
• Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
• Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.