arch/arm64/include/asm/stage2_pgtable.h

Source file repositories/reference/linux-study-clean/arch/arm64/include/asm/stage2_pgtable.h

File Facts

System
Linux kernel
Corpus path
arch/arm64/include/asm/stage2_pgtable.h
Extension
.h
Size
1055 bytes
Lines
34
Domain
Architecture Layer
Bucket
arch/arm64
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.

Dependency Surface

Detected Declarations

Annotated Snippet

#ifndef __ARM64_S2_PGTABLE_H_
#define __ARM64_S2_PGTABLE_H_

#include <linux/pgtable.h>

/*
 * The hardware supports concatenation of up to 16 tables at stage2 entry
 * level and we use the feature whenever possible, which means we resolve 4
 * additional bits of address at the entry level.
 *
 * This implies, the total number of page table levels required for
 * IPA_SHIFT at stage2 expected by the hardware can be calculated using
 * the same logic used for the (non-collapsable) stage1 page tables but for
 * (IPA_SHIFT - 4).
 */
#define stage2_pgtable_levels(ipa)	ARM64_HW_PGTABLE_LEVELS((ipa) - 4)
#define kvm_stage2_levels(mmu)		VTCR_EL2_LVLS((mmu)->vtcr)

/*
 * kvm_mmmu_cache_min_pages() is the number of pages required to install
 * a stage-2 translation. We pre-allocate the entry level page table at
 * the VM creation.
 */
#define kvm_mmu_cache_min_pages(mmu)	(kvm_stage2_levels(mmu) - 1)

#endif	/* __ARM64_S2_PGTABLE_H_ */

Annotation

Implementation Notes