arch/x86/include/asm/pgalloc.h

Source file repositories/reference/linux-study-clean/arch/x86/include/asm/pgalloc.h

File Facts

System
Linux kernel
Corpus path
arch/x86/include/asm/pgalloc.h
Extension
.h
Size
4901 bytes
Lines
162
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.

Dependency Surface

Detected Declarations

Annotated Snippet

static inline int  __paravirt_pgd_alloc(struct mm_struct *mm) { return 0; }

#ifdef CONFIG_PARAVIRT_XXL
#include <asm/paravirt.h>
#else
#define paravirt_pgd_alloc(mm)	__paravirt_pgd_alloc(mm)
static inline void paravirt_pgd_free(struct mm_struct *mm, pgd_t *pgd) {}
static inline void paravirt_alloc_pte(struct mm_struct *mm, unsigned long pfn)	{}
static inline void paravirt_alloc_pmd(struct mm_struct *mm, unsigned long pfn)	{}
static inline void paravirt_alloc_pmd_clone(unsigned long pfn, unsigned long clonepfn,
					    unsigned long start, unsigned long count) {}
static inline void paravirt_alloc_pud(struct mm_struct *mm, unsigned long pfn)	{}
static inline void paravirt_alloc_p4d(struct mm_struct *mm, unsigned long pfn)	{}
static inline void paravirt_release_pte(unsigned long pfn) {}
static inline void paravirt_release_pmd(unsigned long pfn) {}
static inline void paravirt_release_pud(unsigned long pfn) {}
static inline void paravirt_release_p4d(unsigned long pfn) {}
#endif

/*
 * In case of Page Table Isolation active, we acquire two PGDs instead of one.
 * Being order-1, it is both 8k in size and 8k-aligned.  That lets us just
 * flip bit 12 in a pointer to swap between the two 4k halves.
 */
static inline unsigned int pgd_allocation_order(void)
{
	if (cpu_feature_enabled(X86_FEATURE_PTI))
		return 1;
	return 0;
}

/*
 * Allocate and free page tables.
 */
extern pgd_t *pgd_alloc(struct mm_struct *);
extern void pgd_free(struct mm_struct *mm, pgd_t *pgd);

extern pgtable_t pte_alloc_one(struct mm_struct *);

extern void ___pte_free_tlb(struct mmu_gather *tlb, struct page *pte);

static inline void __pte_free_tlb(struct mmu_gather *tlb, struct page *pte,
				  unsigned long address)
{
	___pte_free_tlb(tlb, pte);
}

static inline void pmd_populate_kernel(struct mm_struct *mm,
				       pmd_t *pmd, pte_t *pte)
{
	paravirt_alloc_pte(mm, __pa(pte) >> PAGE_SHIFT);
	set_pmd(pmd, __pmd(__pa(pte) | _PAGE_TABLE));
}

static inline void pmd_populate_kernel_safe(struct mm_struct *mm,
				       pmd_t *pmd, pte_t *pte)
{
	paravirt_alloc_pte(mm, __pa(pte) >> PAGE_SHIFT);
	set_pmd_safe(pmd, __pmd(__pa(pte) | _PAGE_TABLE));
}

static inline void pmd_populate(struct mm_struct *mm, pmd_t *pmd,
				struct page *pte)
{
	unsigned long pfn = page_to_pfn(pte);

	paravirt_alloc_pte(mm, pfn);
	set_pmd(pmd, __pmd(((pteval_t)pfn << PAGE_SHIFT) | _PAGE_TABLE));
}

#if CONFIG_PGTABLE_LEVELS > 2
extern void ___pmd_free_tlb(struct mmu_gather *tlb, pmd_t *pmd);

static inline void __pmd_free_tlb(struct mmu_gather *tlb, pmd_t *pmd,
				  unsigned long address)
{
	___pmd_free_tlb(tlb, pmd);
}

#ifdef CONFIG_X86_PAE
extern void pud_populate(struct mm_struct *mm, pud_t *pudp, pmd_t *pmd);
#else	/* !CONFIG_X86_PAE */
static inline void pud_populate(struct mm_struct *mm, pud_t *pud, pmd_t *pmd)
{
	paravirt_alloc_pmd(mm, __pa(pmd) >> PAGE_SHIFT);
	set_pud(pud, __pud(_PAGE_TABLE | __pa(pmd)));
}

static inline void pud_populate_safe(struct mm_struct *mm, pud_t *pud, pmd_t *pmd)
{

Annotation

Implementation Notes