From d8e7a33df0976459674dece4b630b5d59796ece7 Mon Sep 17 00:00:00 2001 From: Gerald Schaefer Date: Thu, 25 Oct 2012 17:42:50 +0200 Subject: s390/thp: respect page protection in pmd_none() and pmd_present() Similar to pte_none() and pte_present(), the pmd functions should also respect page protection of huge pages, especially PROT_NONE. This patch also simplifies massage_pgprot_pmd() by adding new definitions for huge page protection. Signed-off-by: Gerald Schaefer Signed-off-by: Martin Schwidefsky --- arch/s390/include/asm/pgtable.h | 35 ++++++++++++++++++++++------------- 1 file changed, 22 insertions(+), 13 deletions(-) (limited to 'arch/s390') diff --git a/arch/s390/include/asm/pgtable.h b/arch/s390/include/asm/pgtable.h index dd647c919a66..2d3b7cb26005 100644 --- a/arch/s390/include/asm/pgtable.h +++ b/arch/s390/include/asm/pgtable.h @@ -506,12 +506,15 @@ static inline int pud_bad(pud_t pud) static inline int pmd_present(pmd_t pmd) { - return (pmd_val(pmd) & _SEGMENT_ENTRY_ORIGIN) != 0UL; + unsigned long mask = _SEGMENT_ENTRY_INV | _SEGMENT_ENTRY_RO; + return (pmd_val(pmd) & mask) == _HPAGE_TYPE_NONE || + !(pmd_val(pmd) & _SEGMENT_ENTRY_INV); } static inline int pmd_none(pmd_t pmd) { - return (pmd_val(pmd) & _SEGMENT_ENTRY_INV) != 0UL; + return (pmd_val(pmd) & _SEGMENT_ENTRY_INV) && + !(pmd_val(pmd) & _SEGMENT_ENTRY_RO); } static inline int pmd_large(pmd_t pmd) @@ -1223,6 +1226,11 @@ static inline void __pmd_idte(unsigned long address, pmd_t *pmdp) } #ifdef CONFIG_TRANSPARENT_HUGEPAGE + +#define SEGMENT_NONE __pgprot(_HPAGE_TYPE_NONE) +#define SEGMENT_RO __pgprot(_HPAGE_TYPE_RO) +#define SEGMENT_RW __pgprot(_HPAGE_TYPE_RW) + #define __HAVE_ARCH_PGTABLE_DEPOSIT extern void pgtable_trans_huge_deposit(struct mm_struct *mm, pgtable_t pgtable); @@ -1242,16 +1250,15 @@ static inline void set_pmd_at(struct mm_struct *mm, unsigned long addr, static inline unsigned long massage_pgprot_pmd(pgprot_t pgprot) { - unsigned long pgprot_pmd = 0; - - if (pgprot_val(pgprot) & _PAGE_INVALID) { - if (pgprot_val(pgprot) & _PAGE_SWT) - pgprot_pmd |= _HPAGE_TYPE_NONE; - pgprot_pmd |= _SEGMENT_ENTRY_INV; - } - if (pgprot_val(pgprot) & _PAGE_RO) - pgprot_pmd |= _SEGMENT_ENTRY_RO; - return pgprot_pmd; + /* + * pgprot is PAGE_NONE, PAGE_RO, or PAGE_RW (see __Pxxx / __Sxxx) + * Convert to segment table entry format. + */ + if (pgprot_val(pgprot) == pgprot_val(PAGE_NONE)) + return pgprot_val(SEGMENT_NONE); + if (pgprot_val(pgprot) == pgprot_val(PAGE_RO)) + return pgprot_val(SEGMENT_RO); + return pgprot_val(SEGMENT_RW); } static inline pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot) @@ -1269,7 +1276,9 @@ static inline pmd_t pmd_mkhuge(pmd_t pmd) static inline pmd_t pmd_mkwrite(pmd_t pmd) { - pmd_val(pmd) &= ~_SEGMENT_ENTRY_RO; + /* Do not clobber _HPAGE_TYPE_NONE pages! */ + if (!(pmd_val(pmd) & _SEGMENT_ENTRY_INV)) + pmd_val(pmd) &= ~_SEGMENT_ENTRY_RO; return pmd; } -- cgit v1.2.3