arch/riscv/mm/pageattr.c

Source file repositories/reference/linux-study-clean/arch/riscv/mm/pageattr.c

File Facts

System
Linux kernel
Corpus path
arch/riscv/mm/pageattr.c
Extension
.c
Size
10777 bytes
Lines
471
Domain
Architecture Layer
Bucket
arch/riscv
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

struct pageattr_masks {
	pgprot_t set_mask;
	pgprot_t clear_mask;
};

static unsigned long set_pageattr_masks(unsigned long val, struct mm_walk *walk)
{
	struct pageattr_masks *masks = walk->private;
	unsigned long new_val = val;

	new_val &= ~(pgprot_val(masks->clear_mask));
	new_val |= (pgprot_val(masks->set_mask));

	return new_val;
}

static int pageattr_p4d_entry(p4d_t *p4d, unsigned long addr,
			      unsigned long next, struct mm_walk *walk)
{
	p4d_t val = p4dp_get(p4d);

	if (p4d_leaf(val)) {
		val = __p4d(set_pageattr_masks(p4d_val(val), walk));
		set_p4d(p4d, val);
	}

	return 0;
}

static int pageattr_pud_entry(pud_t *pud, unsigned long addr,
			      unsigned long next, struct mm_walk *walk)
{
	pud_t val = pudp_get(pud);

	if (pud_leaf(val)) {
		val = __pud(set_pageattr_masks(pud_val(val), walk));
		set_pud(pud, val);
	}

	return 0;
}

static int pageattr_pmd_entry(pmd_t *pmd, unsigned long addr,
			      unsigned long next, struct mm_walk *walk)
{
	pmd_t val = pmdp_get(pmd);

	if (pmd_leaf(val)) {
		val = __pmd(set_pageattr_masks(pmd_val(val), walk));
		set_pmd(pmd, val);
	}

	return 0;
}

static int pageattr_pte_entry(pte_t *pte, unsigned long addr,
			      unsigned long next, struct mm_walk *walk)
{
	pte_t val = ptep_get(pte);

	val = __pte(set_pageattr_masks(pte_val(val), walk));
	set_pte(pte, val);

	return 0;
}

static int pageattr_pte_hole(unsigned long addr, unsigned long next,
			     int depth, struct mm_walk *walk)
{
	/* Nothing to do here */
	return 0;
}

static const struct mm_walk_ops pageattr_ops = {
	.p4d_entry = pageattr_p4d_entry,
	.pud_entry = pageattr_pud_entry,
	.pmd_entry = pageattr_pmd_entry,
	.pte_entry = pageattr_pte_entry,
	.pte_hole = pageattr_pte_hole,
	.walk_lock = PGWALK_RDLOCK,
};

#ifdef CONFIG_64BIT
static int __split_linear_mapping_pmd(pud_t *pudp,
				      unsigned long vaddr, unsigned long end)
{
	pmd_t *pmdp;
	unsigned long next;

	pmdp = pmd_offset(pudp, vaddr);

Annotation

Implementation Notes