Commit b28c74e2 authored by Ryan Roberts's avatar Ryan Roberts Committed by Will Deacon
Browse files

arm64/mm: generalize PMD_PRESENT_INVALID for all levels 



As preparation for the next patch, which frees up the PTE_PROT_NONE
present pte and swap pte bit, generalize PMD_PRESENT_INVALID to
PTE_PRESENT_INVALID. This will then be used to mark PROT_NONE ptes (and
entries at any other level) in the next patch.

While we're at it, fix up the swap pte format comment to include
PTE_PRESENT_INVALID. This is not new, it just wasn't previously
documented.

Reviewed-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
Signed-off-by: default avatarRyan Roberts <ryan.roberts@arm.com>
Link: https://lore.kernel.org/r/20240503144604.151095-2-ryan.roberts@arm.com


Signed-off-by: default avatarWill Deacon <will@kernel.org>
parent 0e9df1c9

arch/arm64/include/asm/pgtable-prot.h

+4 −4
Original line number Diff line number Diff line
@@ -21,11 +21,11 @@ 
#define PTE_PROT_NONE		(_AT(pteval_t, 1) << 58) /* only when !PTE_VALID */



/*

 * This bit indicates that the entry is present i.e. pmd_page()

 * still points to a valid huge page in memory even if the pmd

 * has been invalidated.

 * PTE_PRESENT_INVALID=1 & PTE_VALID=0 indicates that the pte's fields should be

 * interpreted according to the HW layout by SW but any attempted HW access to

 * the address will result in a fault. pte_present() returns true.

 */

#define PMD_PRESENT_INVALID	(_AT(pteval_t, 1) << 59) /* only when !PMD_SECT_VALID */

#define PTE_PRESENT_INVALID	(_AT(pteval_t, 1) << 59) /* only when !PTE_VALID */



#define _PROT_DEFAULT		(PTE_TYPE_PAGE | PTE_AF | PTE_SHARED)

#define _PROT_SECT_DEFAULT	(PMD_TYPE_SECT | PMD_SECT_AF | PMD_SECT_S)

arch/arm64/include/asm/pgtable.h

+12 −9
Original line number Diff line number Diff line
@@ -132,6 +132,8 @@ static inline pteval_t __phys_to_pte_val(phys_addr_t phys) 
#define pte_dirty(pte)		(pte_sw_dirty(pte) || pte_hw_dirty(pte))



#define pte_valid(pte)		(!!(pte_val(pte) & PTE_VALID))

#define pte_present_invalid(pte) \

	((pte_val(pte) & (PTE_VALID | PTE_PRESENT_INVALID)) == PTE_PRESENT_INVALID)

/*

 * Execute-only user mappings do not have the PTE_USER bit set. All valid

 * kernel mappings have the PTE_UXN bit set.
@@ -261,6 +263,13 @@ static inline pte_t pte_mkpresent(pte_t pte) 
	return set_pte_bit(pte, __pgprot(PTE_VALID));

}



static inline pte_t pte_mkinvalid(pte_t pte)

{

	pte = set_pte_bit(pte, __pgprot(PTE_PRESENT_INVALID));

	pte = clear_pte_bit(pte, __pgprot(PTE_VALID));

	return pte;

}



static inline pmd_t pmd_mkcont(pmd_t pmd)

{

	return __pmd(pmd_val(pmd) | PMD_SECT_CONT);
@@ -483,7 +492,7 @@ static inline int pmd_protnone(pmd_t pmd) 
}

#endif



#define pmd_present_invalid(pmd)     (!!(pmd_val(pmd) & PMD_PRESENT_INVALID))

#define pmd_present_invalid(pmd)	pte_present_invalid(pmd_pte(pmd))



static inline int pmd_present(pmd_t pmd)

{
@@ -513,14 +522,7 @@ static inline int pmd_trans_huge(pmd_t pmd) 
#define pmd_mkclean(pmd)	pte_pmd(pte_mkclean(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)))



static inline pmd_t pmd_mkinvalid(pmd_t pmd)

{

	pmd = set_pmd_bit(pmd, __pgprot(PMD_PRESENT_INVALID));

	pmd = clear_pmd_bit(pmd, __pgprot(PMD_SECT_VALID));



	return pmd;

}

#define pmd_mkinvalid(pmd)	pte_pmd(pte_mkinvalid(pmd_pte(pmd)))



#define pmd_thp_or_huge(pmd)	(pmd_huge(pmd) || pmd_trans_huge(pmd))
@@ -1258,6 +1260,7 @@ static inline pmd_t pmdp_establish(struct vm_area_struct *vma, 
 *	bits 3-7:	swap type

 *	bits 8-57:	swap offset

 *	bit  58:	PTE_PROT_NONE (must be zero)

 *	bit  59:	PTE_PRESENT_INVALID (must be zero)

 */

#define __SWP_TYPE_SHIFT	3

#define __SWP_TYPE_BITS		5