arch/um/os-Linux/user_syms.c
Source file repositories/reference/linux-study-clean/arch/um/os-Linux/user_syms.c
File Facts
- System
- Linux kernel
- Corpus path
arch/um/os-Linux/user_syms.c- Extension
.c- Size
- 1088 bytes
- Lines
- 38
- Domain
- Architecture Layer
- Bucket
- arch/um
- Inferred role
- Architecture Layer: exported/initcall integration point
- Status
- integration 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.
- Exports symbols or registers init work; inspect boot/module ordering and who consumes the exported contract.
Dependency Surface
linux/types.hlinux/module.h
Detected Declarations
export strstrexport memcpyexport memmoveexport memsetexport __sprintf_chk
Annotated Snippet
// SPDX-License-Identifier: GPL-2.0
#define __NO_FORTIFY
#include <linux/types.h>
#include <linux/module.h>
/*
* This file exports some critical string functions and compiler
* built-in functions (where calls are emitted by the compiler
* itself that we cannot avoid even in kernel code) to modules.
*
* "_user.c" code that previously used exports here such as hostfs
* really should be considered part of the 'hypervisor' and define
* its own API boundary like hostfs does now; don't add exports to
* this file for such cases.
*/
/* If it's not defined, the export is included in lib/string.c.*/
#ifdef __HAVE_ARCH_STRSTR
#undef strstr
EXPORT_SYMBOL(strstr);
#endif
#ifndef __x86_64__
#undef memcpy
extern void *memcpy(void *, const void *, size_t);
EXPORT_SYMBOL(memcpy);
extern void *memmove(void *, const void *, size_t);
EXPORT_SYMBOL(memmove);
#undef memset
extern void *memset(void *, int, size_t);
EXPORT_SYMBOL(memset);
#endif
#ifdef _FORTIFY_SOURCE
extern int __sprintf_chk(char *str, int flag, size_t len, const char *format);
EXPORT_SYMBOL(__sprintf_chk);
#endif
Annotation
- Immediate include surface: `linux/types.h`, `linux/module.h`.
- Detected declarations: `export strstr`, `export memcpy`, `export memmove`, `export memset`, `export __sprintf_chk`.
- Atlas domain: Architecture Layer / arch/um.
- Implementation status: integration implementation candidate.
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.