arch/arm/include/asm/pgalloc.h

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

File Facts

System
Linux kernel
Corpus path
arch/arm/include/asm/pgalloc.h
Extension
.h
Size
3373 bytes
Lines
150
Domain
Architecture Layer
Bucket
arch/arm
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 _ASMARM_PGALLOC_H
#define _ASMARM_PGALLOC_H

#include <linux/pagemap.h>

#include <asm/domain.h>
#include <asm/pgtable-hwdef.h>
#include <asm/processor.h>
#include <asm/cacheflush.h>
#include <asm/tlbflush.h>

#ifdef CONFIG_MMU

#define _PAGE_USER_TABLE	(PMD_TYPE_TABLE | PMD_BIT4 | PMD_DOMAIN(DOMAIN_USER))
#define _PAGE_KERNEL_TABLE	(PMD_TYPE_TABLE | PMD_BIT4 | PMD_DOMAIN(DOMAIN_KERNEL))

#ifdef CONFIG_ARM_LPAE
#define PGD_SIZE		(PTRS_PER_PGD * sizeof(pgd_t))

static inline void pud_populate(struct mm_struct *mm, pud_t *pud, pmd_t *pmd)
{
	set_pud(pud, __pud(__pa(pmd) | PMD_TYPE_TABLE));
}

#else	/* !CONFIG_ARM_LPAE */
#define PGD_SIZE		(PAGE_SIZE << 2)

/*
 * Since we have only two-level page tables, these are trivial
 */
#define pmd_alloc_one(mm,addr)		({ BUG(); ((pmd_t *)2); })
#define pmd_free(mm, pmd)		do { } while (0)
#ifdef CONFIG_KASAN
/* The KASan core unconditionally calls pud_populate() on all architectures */
#define pud_populate(mm,pmd,pte)	do { } while (0)
#else
#define pud_populate(mm,pmd,pte)	BUG()
#endif
#endif	/* CONFIG_ARM_LPAE */

extern pgd_t *pgd_alloc(struct mm_struct *mm);
extern void pgd_free(struct mm_struct *mm, pgd_t *pgd);

static inline void clean_pte_table(pte_t *pte)
{
	clean_dcache_area(pte + PTE_HWTABLE_PTRS, PTE_HWTABLE_SIZE);
}

/*
 * Allocate one PTE table.
 *
 * This actually allocates two hardware PTE tables, but we wrap this up
 * into one table thus:
 *
 *  +------------+
 *  | Linux pt 0 |
 *  +------------+
 *  | Linux pt 1 |
 *  +------------+
 *  |  h/w pt 0  |
 *  +------------+
 *  |  h/w pt 1  |
 *  +------------+
 */

#define __HAVE_ARCH_PTE_ALLOC_ONE_KERNEL
#define __HAVE_ARCH_PTE_ALLOC_ONE
#define __HAVE_ARCH_PGD_FREE
#include <asm-generic/pgalloc.h>

static inline pte_t *
pte_alloc_one_kernel(struct mm_struct *mm)
{
	pte_t *pte = __pte_alloc_one_kernel(mm);

	if (pte)
		clean_pte_table(pte);

	return pte;
}

#ifdef CONFIG_HIGHPTE
#define PGTABLE_HIGHMEM __GFP_HIGHMEM
#else
#define PGTABLE_HIGHMEM 0
#endif

static inline pgtable_t
pte_alloc_one(struct mm_struct *mm)
{

Annotation

Implementation Notes