arch/loongarch/include/asm/sparsemem.h

File Facts

System

Linux kernel

Corpus path

arch/loongarch/include/asm/sparsemem.h

Extension

.h

Size

725 bytes

Lines

27

Domain

Architecture Layer

Bucket

arch/loongarch

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.
• Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.

Dependency Surface

• No C-style include directives detected by the generator.

Detected Declarations

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

Annotated Snippet

#ifndef _LOONGARCH_SPARSEMEM_H
#define _LOONGARCH_SPARSEMEM_H

#ifdef CONFIG_SPARSEMEM

/*
 * SECTION_SIZE_BITS		2^N: how big each section will be
 * MAX_PHYSMEM_BITS		2^N: how much memory we can have in that space
 */
#define SECTION_SIZE_BITS	29 /* 2^29 = Largest Huge Page Size */
#define MAX_PHYSMEM_BITS	48

#ifdef CONFIG_SPARSEMEM_VMEMMAP
#define VMEMMAP_SIZE	(sizeof(struct page) * (1UL << (cpu_pabits + 1 - PAGE_SHIFT)))
#endif

#endif /* CONFIG_SPARSEMEM */

#ifndef VMEMMAP_SIZE
#define VMEMMAP_SIZE	0	/* 1, For FLATMEM; 2, For SPARSEMEM without VMEMMAP. */
#endif

#define INIT_MEMBLOCK_RESERVED_REGIONS	(INIT_MEMBLOCK_REGIONS + NR_CPUS)

#endif /* _LOONGARCH_SPARSEMEM_H */

Annotation

• Atlas domain: Architecture Layer / arch/loongarch.
• 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.