Le 15/02/2023 à 03:01, Rohan McLure a écrit : > Add the following helpers for detecting whether a page table entry > is a leaf and is accessible to user space. > > * pte_user_accessible_page > * pmd_user_accessible_page > * pud_user_accessible_page > > Also implement missing pud_user definitions for both Book3S/nohash 64-bit > systems, and pmd_user for Book3S/nohash 32-bit systems. > > Signed-off-by: Rohan McLure <rmcl...@linux.ibm.com>
Reviewed-by: Christophe Leroy <christophe.le...@csgroup.eu> > --- > V2: Provide missing pud_user implementations, use p{u,m}d_is_leaf. > V3: Provide missing pmd_user implementations as stubs in 32-bit. > V4: Use pmd_leaf, pud_leaf, and define pmd_user for 32 Book3E with > static inline method rather than macro. > --- > arch/powerpc/include/asm/book3s/32/pgtable.h | 4 ++++ > arch/powerpc/include/asm/book3s/64/pgtable.h | 10 ++++++++++ > arch/powerpc/include/asm/nohash/32/pgtable.h | 5 +++++ > arch/powerpc/include/asm/nohash/64/pgtable.h | 10 ++++++++++ > arch/powerpc/include/asm/pgtable.h | 15 +++++++++++++++ > 5 files changed, 44 insertions(+) > > diff --git a/arch/powerpc/include/asm/book3s/32/pgtable.h > b/arch/powerpc/include/asm/book3s/32/pgtable.h > index a090cb13a4a0..afd672e84791 100644 > --- a/arch/powerpc/include/asm/book3s/32/pgtable.h > +++ b/arch/powerpc/include/asm/book3s/32/pgtable.h > @@ -516,6 +516,10 @@ static inline pte_t pte_modify(pte_t pte, pgprot_t > newprot) > return __pte((pte_val(pte) & _PAGE_CHG_MASK) | pgprot_val(newprot)); > } > > +static inline bool pmd_user(pmd_t pmd) > +{ > + return 0; > +} > > > /* This low level function performs the actual PTE insertion > diff --git a/arch/powerpc/include/asm/book3s/64/pgtable.h > b/arch/powerpc/include/asm/book3s/64/pgtable.h > index df5ee856444d..a6ed93d01da1 100644 > --- a/arch/powerpc/include/asm/book3s/64/pgtable.h > +++ b/arch/powerpc/include/asm/book3s/64/pgtable.h > @@ -538,6 +538,16 @@ static inline bool pte_user(pte_t pte) > return !(pte_raw(pte) & cpu_to_be64(_PAGE_PRIVILEGED)); > } > > +static inline bool pmd_user(pmd_t pmd) > +{ > + return !(pmd_raw(pmd) & cpu_to_be64(_PAGE_PRIVILEGED)); > +} > + > +static inline bool pud_user(pud_t pud) > +{ > + return !(pud_raw(pud) & cpu_to_be64(_PAGE_PRIVILEGED)); > +} > + > #define pte_access_permitted pte_access_permitted > static inline bool pte_access_permitted(pte_t pte, bool write) > { > diff --git a/arch/powerpc/include/asm/nohash/32/pgtable.h > b/arch/powerpc/include/asm/nohash/32/pgtable.h > index 70edad44dff6..d953533c56ff 100644 > --- a/arch/powerpc/include/asm/nohash/32/pgtable.h > +++ b/arch/powerpc/include/asm/nohash/32/pgtable.h > @@ -209,6 +209,11 @@ static inline void pmd_clear(pmd_t *pmdp) > *pmdp = __pmd(0); > } > > +static inline bool pmd_user(pmd_t pmd) > +{ > + return false; > +} > + > /* > * PTE updates. This function is called whenever an existing > * valid PTE is updated. This does -not- include set_pte_at() > diff --git a/arch/powerpc/include/asm/nohash/64/pgtable.h > b/arch/powerpc/include/asm/nohash/64/pgtable.h > index d391a45e0f11..14e69ebad31f 100644 > --- a/arch/powerpc/include/asm/nohash/64/pgtable.h > +++ b/arch/powerpc/include/asm/nohash/64/pgtable.h > @@ -123,6 +123,11 @@ static inline pte_t pmd_pte(pmd_t pmd) > return __pte(pmd_val(pmd)); > } > > +static inline bool pmd_user(pmd_t pmd) > +{ > + return (pmd_val(pmd) & _PAGE_USER) == _PAGE_USER; > +} > + > #define pmd_none(pmd) (!pmd_val(pmd)) > #define pmd_bad(pmd) (!is_kernel_addr(pmd_val(pmd)) \ > || (pmd_val(pmd) & PMD_BAD_BITS)) > @@ -164,6 +169,11 @@ static inline pte_t pud_pte(pud_t pud) > return __pte(pud_val(pud)); > } > > +static inline bool pud_user(pud_t pud) > +{ > + return (pud_val(pud) & _PAGE_USER) == _PAGE_USER; > +} > + > static inline pud_t pte_pud(pte_t pte) > { > return __pud(pte_val(pte)); > diff --git a/arch/powerpc/include/asm/pgtable.h > b/arch/powerpc/include/asm/pgtable.h > index ad0829f816e9..b76fdb80b6c9 100644 > --- a/arch/powerpc/include/asm/pgtable.h > +++ b/arch/powerpc/include/asm/pgtable.h > @@ -167,6 +167,21 @@ static inline int pud_pfn(pud_t pud) > } > #endif > > +static inline bool pte_user_accessible_page(pte_t pte) > +{ > + return pte_present(pte) && pte_user(pte); > +} > + > +static inline bool pmd_user_accessible_page(pmd_t pmd) > +{ > + return pmd_leaf(pmd) && pmd_present(pmd) && pmd_user(pmd); > +} > + > +static inline bool pud_user_accessible_page(pud_t pud) > +{ > + return pud_leaf(pud) && pud_present(pud) && pud_user(pud); > +} > + > #endif /* __ASSEMBLY__ */ > > #endif /* _ASM_POWERPC_PGTABLE_H */