arch/um/include/asm/io.h

File Facts

System

Linux kernel

Corpus path

arch/um/include/asm/io.h

Extension

.h

Size

478 bytes

Lines

27

Domain

Architecture Layer

Bucket

arch/um

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.

Dependency Surface

• linux/types.h
• asm-generic/logic_io.h
• asm-generic/io.h

Detected Declarations

• function iounmap

Annotated Snippet

#ifndef _ASM_UM_IO_H
#define _ASM_UM_IO_H
#include <linux/types.h>

/* get emulated iomem (if desired) */
#include <asm-generic/logic_io.h>

#ifndef ioremap
#define ioremap ioremap
static inline void __iomem *ioremap(phys_addr_t offset, size_t size)
{
	return NULL;
}
#endif /* ioremap */

#ifndef iounmap
#define iounmap iounmap
static inline void iounmap(void __iomem *addr)
{
}
#endif /* iounmap */

#include <asm-generic/io.h>

#endif

Annotation

• Immediate include surface: `linux/types.h`, `asm-generic/logic_io.h`, `asm-generic/io.h`.
• Detected declarations: `function iounmap`.
• Atlas domain: Architecture Layer / arch/um.
• Implementation status: source 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.