Commit 9c7e535f authored by Steve Capper's avatar Steve Capper Committed by Catalin Marinas
Browse files

arm64: mm: Route pmd thp functions through pte equivalents 



Rather than have separate hugetlb and transparent huge page pmd
manipulation functions, re-wire our thp functions to simply call the
pte equivalents.

This allows THP to take advantage of the new PTE_WRITE logic introduced
in:
  c2c93e5b arm64: mm: Introduce PTE_WRITE

To represent splitting THPs we use the PTE_SPECIAL bit as this is not
used for pmds.

Signed-off-by: default avatarSteve Capper <steve.capper@linaro.org>
Signed-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
parent c209f799

arch/arm64/include/asm/pgtable.h

+24 −28
Original line number Diff line number Diff line
@@ -227,36 +227,36 @@ static inline void set_pte_at(struct mm_struct *mm, unsigned long addr, 


#define __HAVE_ARCH_PTE_SPECIAL



/*

 * Software PMD bits for THP

 */

static inline pte_t pmd_pte(pmd_t pmd)

{

	return __pte(pmd_val(pmd));

}



#define PMD_SECT_DIRTY		(_AT(pmdval_t, 1) << 55)

#define PMD_SECT_SPLITTING	(_AT(pmdval_t, 1) << 57)

static inline pmd_t pte_pmd(pte_t pte)

{

	return __pmd(pte_val(pte));

}



/*

 * THP definitions.

 */

#define pmd_young(pmd)		(pmd_val(pmd) & PMD_SECT_AF)



#define __HAVE_ARCH_PMD_WRITE

#define pmd_write(pmd)		(!(pmd_val(pmd) & PMD_SECT_RDONLY))



#ifdef CONFIG_TRANSPARENT_HUGEPAGE

#define pmd_trans_huge(pmd)	(pmd_val(pmd) && !(pmd_val(pmd) & PMD_TABLE_BIT))

#define pmd_trans_splitting(pmd) (pmd_val(pmd) & PMD_SECT_SPLITTING)

#define pmd_trans_splitting(pmd)	pte_special(pmd_pte(pmd))

#endif



#define PMD_BIT_FUNC(fn,op) \

static inline pmd_t pmd_##fn(pmd_t pmd) { pmd_val(pmd) op; return pmd; }

#define pmd_young(pmd)		pte_young(pmd_pte(pmd))

#define pmd_wrprotect(pmd)	pte_pmd(pte_wrprotect(pmd_pte(pmd)))

#define pmd_mksplitting(pmd)	pte_pmd(pte_mkspecial(pmd_pte(pmd)))

#define pmd_mkold(pmd)		pte_pmd(pte_mkold(pmd_pte(pmd)))

#define pmd_mkwrite(pmd)	pte_pmd(pte_mkwrite(pmd_pte(pmd)))

#define pmd_mkdirty(pmd)	pte_pmd(pte_mkdirty(pmd_pte(pmd)))

#define pmd_mkyoung(pmd)	pte_pmd(pte_mkyoung(pmd_pte(pmd)))

#define pmd_mknotpresent(pmd)	(__pmd(pmd_val(pmd) &= ~PMD_TYPE_MASK))



PMD_BIT_FUNC(wrprotect,	|= PMD_SECT_RDONLY);

PMD_BIT_FUNC(mkold,	&= ~PMD_SECT_AF);

PMD_BIT_FUNC(mksplitting, |= PMD_SECT_SPLITTING);

PMD_BIT_FUNC(mkwrite,   &= ~PMD_SECT_RDONLY);

PMD_BIT_FUNC(mkdirty,   |= PMD_SECT_DIRTY);

PMD_BIT_FUNC(mkyoung,   |= PMD_SECT_AF);

PMD_BIT_FUNC(mknotpresent, &= ~PMD_TYPE_MASK);

#define __HAVE_ARCH_PMD_WRITE

#define pmd_write(pmd)		pte_write(pmd_pte(pmd))



#define pmd_mkhuge(pmd)		(__pmd(pmd_val(pmd) & ~PMD_TABLE_BIT))
@@ -266,15 +266,6 @@ PMD_BIT_FUNC(mknotpresent, &= ~PMD_TYPE_MASK); 


#define pmd_page(pmd)           pfn_to_page(__phys_to_pfn(pmd_val(pmd) & PHYS_MASK))



static inline pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot)

{

	const pmdval_t mask = PMD_SECT_USER | PMD_SECT_PXN | PMD_SECT_UXN |

			      PMD_SECT_RDONLY | PMD_SECT_PROT_NONE |

			      PMD_SECT_VALID;

	pmd_val(pmd) = (pmd_val(pmd) & ~mask) | (pgprot_val(newprot) & mask);

	return pmd;

}



#define set_pmd_at(mm, addr, pmdp, pmd)	set_pmd(pmdp, pmd)



static inline int has_transparent_hugepage(void)
@@ -383,6 +374,11 @@ static inline pte_t pte_modify(pte_t pte, pgprot_t newprot) 
	return pte;

}



static inline pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot)

{

	return pte_pmd(pte_modify(pmd_pte(pmd), newprot));

}



extern pgd_t swapper_pg_dir[PTRS_PER_PGD];

extern pgd_t idmap_pg_dir[PTRS_PER_PGD];

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