arch/x86/include/asm/page.h
Source file repositories/reference/linux-study-clean/arch/x86/include/asm/page.h
File Facts
- System
- Linux kernel
- Corpus path
arch/x86/include/asm/page.h- Extension
.h- Size
- 2383 bytes
- Lines
- 90
- Domain
- Architecture Layer
- Bucket
- arch/x86
- 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
linux/types.hasm/page_types.hasm/page_64.hasm/page_32.hlinux/range.hasm-generic/memory_model.hasm-generic/getorder.h
Detected Declarations
struct pagefunction copy_user_pagefunction __canonical_addressfunction __is_canonical_address
Annotated Snippet
#ifndef _ASM_X86_PAGE_H
#define _ASM_X86_PAGE_H
#include <linux/types.h>
#ifdef __KERNEL__
#include <asm/page_types.h>
#ifdef CONFIG_X86_64
#include <asm/page_64.h>
#else
#include <asm/page_32.h>
#endif /* CONFIG_X86_64 */
#ifndef __ASSEMBLER__
struct page;
#include <linux/range.h>
extern struct range pfn_mapped[];
extern int nr_pfn_mapped;
static inline void copy_user_page(void *to, void *from, unsigned long vaddr,
struct page *topage)
{
copy_page(to, from);
}
#define vma_alloc_zeroed_movable_folio(vma, vaddr) \
vma_alloc_folio(GFP_HIGHUSER_MOVABLE | __GFP_ZERO, 0, vma, vaddr)
#ifndef __pa
#define __pa(x) __phys_addr((unsigned long)(x))
#endif
#define __pa_nodebug(x) __phys_addr_nodebug((unsigned long)(x))
/* __pa_symbol should be used for C visible symbols.
This seems to be the official gcc blessed way to do such arithmetic. */
/*
* We need __phys_reloc_hide() here because gcc may assume that there is no
* overflow during __pa() calculation and can optimize it unexpectedly.
* Newer versions of gcc provide -fno-strict-overflow switch to handle this
* case properly. Once all supported versions of gcc understand it, we can
* remove this Voodoo magic stuff. (i.e. once gcc3.x is deprecated)
*/
#define __pa_symbol(x) \
__phys_addr_symbol(__phys_reloc_hide((unsigned long)(x)))
#ifndef __va
#define __va(x) ((void *)((unsigned long)(x)+PAGE_OFFSET))
#endif
#define __boot_va(x) __va(x)
#define __boot_pa(x) __pa(x)
/*
* virt_to_page(kaddr) returns a valid pointer if and only if
* virt_addr_valid(kaddr) returns true.
*/
#define virt_to_page(kaddr) pfn_to_page(__pa(kaddr) >> PAGE_SHIFT)
extern bool __virt_addr_valid(unsigned long kaddr);
#define virt_addr_valid(kaddr) __virt_addr_valid((unsigned long) (kaddr))
static __always_inline void *pfn_to_kaddr(unsigned long pfn)
{
return __va(pfn << PAGE_SHIFT);
}
static __always_inline u64 __canonical_address(u64 vaddr, u8 vaddr_bits)
{
return ((s64)vaddr << (64 - vaddr_bits)) >> (64 - vaddr_bits);
}
static __always_inline u64 __is_canonical_address(u64 vaddr, u8 vaddr_bits)
{
return __canonical_address(vaddr, vaddr_bits) == vaddr;
}
#endif /* __ASSEMBLER__ */
#include <asm-generic/memory_model.h>
#include <asm-generic/getorder.h>
#define HAVE_ARCH_HUGETLB_UNMAPPED_AREA
#endif /* __KERNEL__ */
#endif /* _ASM_X86_PAGE_H */
Annotation
- Immediate include surface: `linux/types.h`, `asm/page_types.h`, `asm/page_64.h`, `asm/page_32.h`, `linux/range.h`, `asm-generic/memory_model.h`, `asm-generic/getorder.h`.
- Detected declarations: `struct page`, `function copy_user_page`, `function __canonical_address`, `function __is_canonical_address`.
- Atlas domain: Architecture Layer / arch/x86.
- 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.