tools/include/linux/pfn.h

File Facts

System

Linux kernel

Corpus path

tools/include/linux/pfn.h

Extension

.h

Size

332 bytes

Lines

12

Domain

Support Tooling And Documentation

Bucket

tools

Inferred role

Support Tooling And Documentation: implementation source

Status

source implementation candidate

Why This File Exists

Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.

• Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.

Dependency Surface

• linux/mm.h

Detected Declarations

• No top-level syscall, struct, function, initcall, or export declaration detected by the generator.

Annotated Snippet

#ifndef _TOOLS_LINUX_PFN_H_
#define _TOOLS_LINUX_PFN_H_

#include <linux/mm.h>

#define PFN_UP(x)	(((x) + PAGE_SIZE - 1) >> PAGE_SHIFT)
#define PFN_DOWN(x)	((x) >> PAGE_SHIFT)
#define PFN_PHYS(x)	((phys_addr_t)(x) << PAGE_SHIFT)
#define PHYS_PFN(x)	((unsigned long)((x) >> PAGE_SHIFT))
#endif

Annotation

• Immediate include surface: `linux/mm.h`.
• Atlas domain: Support Tooling And Documentation / tools.
• 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.