arch/xtensa/include/asm/fixmap.h
Source file repositories/reference/linux-study-clean/arch/xtensa/include/asm/fixmap.h
File Facts
- System
- Linux kernel
- Corpus path
arch/xtensa/include/asm/fixmap.h- Extension
.h- Size
- 1106 bytes
- Lines
- 39
- Domain
- Architecture Layer
- Bucket
- arch/xtensa
- 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/threads.hlinux/pgtable.hasm/kmap_size.hasm-generic/fixmap.h
Detected Declarations
enum fixed_addresses
Annotated Snippet
#ifndef _ASM_FIXMAP_H
#define _ASM_FIXMAP_H
#ifdef CONFIG_HIGHMEM
#include <linux/threads.h>
#include <linux/pgtable.h>
#include <asm/kmap_size.h>
/* The map slots for temporary mappings via kmap_atomic/local(). */
enum fixed_addresses {
FIX_KMAP_BEGIN,
FIX_KMAP_END = FIX_KMAP_BEGIN +
(KM_MAX_IDX * NR_CPUS * DCACHE_N_COLORS) - 1,
__end_of_fixed_addresses
};
#define FIXADDR_END (XCHAL_KSEG_CACHED_VADDR - PAGE_SIZE)
#define FIXADDR_SIZE (__end_of_fixed_addresses << PAGE_SHIFT)
/* Enforce that FIXADDR_START is PMD aligned to handle cache aliasing */
#define FIXADDR_START ((FIXADDR_END - FIXADDR_SIZE) & PMD_MASK)
#define FIXADDR_TOP (FIXADDR_START + FIXADDR_SIZE - PAGE_SIZE)
#include <asm-generic/fixmap.h>
#endif /* CONFIG_HIGHMEM */
#endif
Annotation
- Immediate include surface: `linux/threads.h`, `linux/pgtable.h`, `asm/kmap_size.h`, `asm-generic/fixmap.h`.
- Detected declarations: `enum fixed_addresses`.
- Atlas domain: Architecture Layer / arch/xtensa.
- 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.