Commit 1d37713f authored by Ryan Roberts's avatar Ryan Roberts Committed by Catalin Marinas
Browse files

arm64: mm: Remove pmd_sect() and pud_sect() 



The semantics of pXd_leaf() are very similar to pXd_sect(). The only
difference is that pXd_sect() only considers it a section if PTE_VALID
is set, whereas pXd_leaf() permits both "valid" and "present-invalid"
types.

Using pXd_sect() has caused issues now that large leaf entries can be
present-invalid since commit a166563e ("arm64: mm: support large
block mapping when rodata=full"), so let's just remove the API and
standardize on pXd_leaf().

There are a few callsites of the form pXd_leaf(READ_ONCE(*pXdp)). This
was previously fine for the pXd_sect() macro because it only evaluated
its argument once. But pXd_leaf() evaluates its argument multiple times.
So let's avoid unintended side effects by reimplementing pXd_leaf() as
an inline function.

Signed-off-by: default avatarRyan Roberts <ryan.roberts@arm.com>
Signed-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
parent 15bfba1a

arch/arm64/include/asm/pgtable.h

+12 −7
Original line number Diff line number Diff line
@@ -784,9 +784,13 @@ extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn, 


#define pmd_table(pmd)		((pmd_val(pmd) & PMD_TYPE_MASK) == \

				 PMD_TYPE_TABLE)

#define pmd_sect(pmd)		((pmd_val(pmd) & PMD_TYPE_MASK) == \

				 PMD_TYPE_SECT)

#define pmd_leaf(pmd)		(pmd_present(pmd) && !pmd_table(pmd))



#define pmd_leaf pmd_leaf

static inline bool pmd_leaf(pmd_t pmd)

{

	return pmd_present(pmd) && !pmd_table(pmd);

}



#define pmd_bad(pmd)		(!pmd_table(pmd))



#define pmd_leaf_size(pmd)	(pmd_cont(pmd) ? CONT_PMD_SIZE : PMD_SIZE)
@@ -804,11 +808,8 @@ static inline int pmd_trans_huge(pmd_t pmd) 
#endif /* CONFIG_TRANSPARENT_HUGEPAGE */



#if defined(CONFIG_ARM64_64K_PAGES) || CONFIG_PGTABLE_LEVELS < 3

static inline bool pud_sect(pud_t pud) { return false; }

static inline bool pud_table(pud_t pud) { return true; }

#else

#define pud_sect(pud)		((pud_val(pud) & PUD_TYPE_MASK) == \

				 PUD_TYPE_SECT)

#define pud_table(pud)		((pud_val(pud) & PUD_TYPE_MASK) == \

				 PUD_TYPE_TABLE)

#endif
@@ -878,7 +879,11 @@ static inline unsigned long pmd_page_vaddr(pmd_t pmd) 
				 PUD_TYPE_TABLE)

#define pud_present(pud)	pte_present(pud_pte(pud))

#ifndef __PAGETABLE_PMD_FOLDED

#define pud_leaf(pud)		(pud_present(pud) && !pud_table(pud))

#define pud_leaf pud_leaf

static inline bool pud_leaf(pud_t pud)

{

	return pud_present(pud) && !pud_table(pud);

}

#else

#define pud_leaf(pud)		false

#endif

arch/arm64/mm/mmu.c

+9 −9
Original line number Diff line number Diff line
@@ -204,7 +204,7 @@ static int alloc_init_cont_pte(pmd_t *pmdp, unsigned long addr, 
	pmd_t pmd = READ_ONCE(*pmdp);

	pte_t *ptep;



	BUG_ON(pmd_sect(pmd));

	BUG_ON(pmd_leaf(pmd));

	if (pmd_none(pmd)) {

		pmdval_t pmdval = PMD_TYPE_TABLE | PMD_TABLE_UXN | PMD_TABLE_AF;

		phys_addr_t pte_phys;
@@ -303,7 +303,7 @@ static int alloc_init_cont_pmd(pud_t *pudp, unsigned long addr, 
	/*

	 * Check for initial section mappings in the pgd/pud.

	 */

	BUG_ON(pud_sect(pud));

	BUG_ON(pud_leaf(pud));

	if (pud_none(pud)) {

		pudval_t pudval = PUD_TYPE_TABLE | PUD_TABLE_UXN | PUD_TABLE_AF;

		phys_addr_t pmd_phys;
@@ -1503,7 +1503,7 @@ static void unmap_hotplug_pmd_range(pud_t *pudp, unsigned long addr, 
			continue;



		WARN_ON(!pmd_present(pmd));

		if (pmd_sect(pmd)) {

		if (pmd_leaf(pmd)) {

			pmd_clear(pmdp);



			/*
@@ -1536,7 +1536,7 @@ static void unmap_hotplug_pud_range(p4d_t *p4dp, unsigned long addr, 
			continue;



		WARN_ON(!pud_present(pud));

		if (pud_sect(pud)) {

		if (pud_leaf(pud)) {

			pud_clear(pudp);



			/*
@@ -1650,7 +1650,7 @@ static void free_empty_pmd_table(pud_t *pudp, unsigned long addr, 
		if (pmd_none(pmd))

			continue;



		WARN_ON(!pmd_present(pmd) || !pmd_table(pmd) || pmd_sect(pmd));

		WARN_ON(!pmd_present(pmd) || !pmd_table(pmd));

		free_empty_pte_table(pmdp, addr, next, floor, ceiling);

	} while (addr = next, addr < end);
@@ -1690,7 +1690,7 @@ static void free_empty_pud_table(p4d_t *p4dp, unsigned long addr, 
		if (pud_none(pud))

			continue;



		WARN_ON(!pud_present(pud) || !pud_table(pud) || pud_sect(pud));

		WARN_ON(!pud_present(pud) || !pud_table(pud));

		free_empty_pmd_table(pudp, addr, next, floor, ceiling);

	} while (addr = next, addr < end);
@@ -1786,7 +1786,7 @@ int __meminit vmemmap_check_pmd(pmd_t *pmdp, int node, 
{

	vmemmap_verify((pte_t *)pmdp, node, addr, next);



	return pmd_sect(READ_ONCE(*pmdp));

	return pmd_leaf(READ_ONCE(*pmdp));

}



int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node,
@@ -1850,7 +1850,7 @@ void p4d_clear_huge(p4d_t *p4dp) 


int pud_clear_huge(pud_t *pudp)

{

	if (!pud_sect(READ_ONCE(*pudp)))

	if (!pud_leaf(READ_ONCE(*pudp)))

		return 0;

	pud_clear(pudp);

	return 1;
@@ -1858,7 +1858,7 @@ int pud_clear_huge(pud_t *pudp) 


int pmd_clear_huge(pmd_t *pmdp)

{

	if (!pmd_sect(READ_ONCE(*pmdp)))

	if (!pmd_leaf(READ_ONCE(*pmdp)))

		return 0;

	pmd_clear(pmdp);

	return 1;