| Message ID | 20210809152448.1810400-17-qperret@google.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Track shared pages at EL2 in protected mode | expand |
Hi Quentin, On Mon, Aug 9, 2021 at 5:25 PM Quentin Perret <qperret@google.com> wrote: > > Introduce helper functions in the KVM stage-2 and stage-1 page-table > manipulation library allowing to retrieve the enum kvm_pgtable_prot of a > PTE. This will be useful to implement custom walkers outside of > pgtable.c. > > Signed-off-by: Quentin Perret <qperret@google.com> > --- Reviewed-by: Fuad Tabba <tabba@google.com> Thanks, /fuad > arch/arm64/include/asm/kvm_pgtable.h | 20 +++++++++++++++ > arch/arm64/kvm/hyp/pgtable.c | 37 ++++++++++++++++++++++++++++ > 2 files changed, 57 insertions(+) > > diff --git a/arch/arm64/include/asm/kvm_pgtable.h b/arch/arm64/include/asm/kvm_pgtable.h > index ff9d52f8073a..f1651e0153ad 100644 > --- a/arch/arm64/include/asm/kvm_pgtable.h > +++ b/arch/arm64/include/asm/kvm_pgtable.h > @@ -506,4 +506,24 @@ int kvm_pgtable_walk(struct kvm_pgtable *pgt, u64 addr, u64 size, > */ > int kvm_pgtable_get_leaf(struct kvm_pgtable *pgt, u64 addr, > kvm_pte_t *ptep, u32 *level); > + > +/** > + * kvm_pgtable_stage2_pte_prot() - Retrieve the protection attributes of a > + * stage-2 Page-Table Entry. > + * @pte: Page-table entry > + * > + * Return: protection attributes of the page-table entry in the enum > + * kvm_pgtable_prot format. > + */ > +enum kvm_pgtable_prot kvm_pgtable_stage2_pte_prot(kvm_pte_t pte); > + > +/** > + * kvm_pgtable_hyp_pte_prot() - Retrieve the protection attributes of a stage-1 > + * Page-Table Entry. > + * @pte: Page-table entry > + * > + * Return: protection attributes of the page-table entry in the enum > + * kvm_pgtable_prot format. > + */ > +enum kvm_pgtable_prot kvm_pgtable_hyp_pte_prot(kvm_pte_t pte); > #endif /* __ARM64_KVM_PGTABLE_H__ */ > diff --git a/arch/arm64/kvm/hyp/pgtable.c b/arch/arm64/kvm/hyp/pgtable.c > index cff744136044..f8ceebe4982e 100644 > --- a/arch/arm64/kvm/hyp/pgtable.c > +++ b/arch/arm64/kvm/hyp/pgtable.c > @@ -363,6 +363,26 @@ static int hyp_set_prot_attr(enum kvm_pgtable_prot prot, kvm_pte_t *ptep) > return 0; > } > > +enum kvm_pgtable_prot kvm_pgtable_hyp_pte_prot(kvm_pte_t pte) > +{ > + enum kvm_pgtable_prot prot = pte & KVM_PTE_LEAF_ATTR_HI_SW; > + u32 ap; > + > + if (!kvm_pte_valid(pte)) > + return prot; > + > + if (!(pte & KVM_PTE_LEAF_ATTR_HI_S1_XN)) > + prot |= KVM_PGTABLE_PROT_X; > + > + ap = FIELD_GET(KVM_PTE_LEAF_ATTR_LO_S1_AP, pte); > + if (ap == KVM_PTE_LEAF_ATTR_LO_S1_AP_RO) > + prot |= KVM_PGTABLE_PROT_R; > + else if (ap == KVM_PTE_LEAF_ATTR_LO_S1_AP_RW) > + prot |= KVM_PGTABLE_PROT_RW; > + > + return prot; > +} > + > static bool hyp_pte_needs_update(kvm_pte_t old, kvm_pte_t new) > { > /* > @@ -565,6 +585,23 @@ static int stage2_set_prot_attr(struct kvm_pgtable *pgt, enum kvm_pgtable_prot p > return 0; > } > > +enum kvm_pgtable_prot kvm_pgtable_stage2_pte_prot(kvm_pte_t pte) > +{ > + enum kvm_pgtable_prot prot = pte & KVM_PTE_LEAF_ATTR_HI_SW; > + > + if (!kvm_pte_valid(pte)) > + return prot; > + > + if (pte & KVM_PTE_LEAF_ATTR_LO_S2_S2AP_R) > + prot |= KVM_PGTABLE_PROT_R; > + if (pte & KVM_PTE_LEAF_ATTR_LO_S2_S2AP_W) > + prot |= KVM_PGTABLE_PROT_W; > + if (!(pte & KVM_PTE_LEAF_ATTR_HI_S2_XN)) > + prot |= KVM_PGTABLE_PROT_X; > + > + return prot; > +} > + > static bool stage2_pte_needs_update(kvm_pte_t old, kvm_pte_t new) > { > if (!kvm_pte_valid(old) || !kvm_pte_valid(new)) > -- > 2.32.0.605.g8dce9f2422-goog >
diff --git a/arch/arm64/include/asm/kvm_pgtable.h b/arch/arm64/include/asm/kvm_pgtable.h index ff9d52f8073a..f1651e0153ad 100644 --- a/arch/arm64/include/asm/kvm_pgtable.h +++ b/arch/arm64/include/asm/kvm_pgtable.h @@ -506,4 +506,24 @@ int kvm_pgtable_walk(struct kvm_pgtable *pgt, u64 addr, u64 size, */ int kvm_pgtable_get_leaf(struct kvm_pgtable *pgt, u64 addr, kvm_pte_t *ptep, u32 *level); + +/** + * kvm_pgtable_stage2_pte_prot() - Retrieve the protection attributes of a + * stage-2 Page-Table Entry. + * @pte: Page-table entry + * + * Return: protection attributes of the page-table entry in the enum + * kvm_pgtable_prot format. + */ +enum kvm_pgtable_prot kvm_pgtable_stage2_pte_prot(kvm_pte_t pte); + +/** + * kvm_pgtable_hyp_pte_prot() - Retrieve the protection attributes of a stage-1 + * Page-Table Entry. + * @pte: Page-table entry + * + * Return: protection attributes of the page-table entry in the enum + * kvm_pgtable_prot format. + */ +enum kvm_pgtable_prot kvm_pgtable_hyp_pte_prot(kvm_pte_t pte); #endif /* __ARM64_KVM_PGTABLE_H__ */ diff --git a/arch/arm64/kvm/hyp/pgtable.c b/arch/arm64/kvm/hyp/pgtable.c index cff744136044..f8ceebe4982e 100644 --- a/arch/arm64/kvm/hyp/pgtable.c +++ b/arch/arm64/kvm/hyp/pgtable.c @@ -363,6 +363,26 @@ static int hyp_set_prot_attr(enum kvm_pgtable_prot prot, kvm_pte_t *ptep) return 0; } +enum kvm_pgtable_prot kvm_pgtable_hyp_pte_prot(kvm_pte_t pte) +{ + enum kvm_pgtable_prot prot = pte & KVM_PTE_LEAF_ATTR_HI_SW; + u32 ap; + + if (!kvm_pte_valid(pte)) + return prot; + + if (!(pte & KVM_PTE_LEAF_ATTR_HI_S1_XN)) + prot |= KVM_PGTABLE_PROT_X; + + ap = FIELD_GET(KVM_PTE_LEAF_ATTR_LO_S1_AP, pte); + if (ap == KVM_PTE_LEAF_ATTR_LO_S1_AP_RO) + prot |= KVM_PGTABLE_PROT_R; + else if (ap == KVM_PTE_LEAF_ATTR_LO_S1_AP_RW) + prot |= KVM_PGTABLE_PROT_RW; + + return prot; +} + static bool hyp_pte_needs_update(kvm_pte_t old, kvm_pte_t new) { /* @@ -565,6 +585,23 @@ static int stage2_set_prot_attr(struct kvm_pgtable *pgt, enum kvm_pgtable_prot p return 0; } +enum kvm_pgtable_prot kvm_pgtable_stage2_pte_prot(kvm_pte_t pte) +{ + enum kvm_pgtable_prot prot = pte & KVM_PTE_LEAF_ATTR_HI_SW; + + if (!kvm_pte_valid(pte)) + return prot; + + if (pte & KVM_PTE_LEAF_ATTR_LO_S2_S2AP_R) + prot |= KVM_PGTABLE_PROT_R; + if (pte & KVM_PTE_LEAF_ATTR_LO_S2_S2AP_W) + prot |= KVM_PGTABLE_PROT_W; + if (!(pte & KVM_PTE_LEAF_ATTR_HI_S2_XN)) + prot |= KVM_PGTABLE_PROT_X; + + return prot; +} + static bool stage2_pte_needs_update(kvm_pte_t old, kvm_pte_t new) { if (!kvm_pte_valid(old) || !kvm_pte_valid(new))
Introduce helper functions in the KVM stage-2 and stage-1 page-table manipulation library allowing to retrieve the enum kvm_pgtable_prot of a PTE. This will be useful to implement custom walkers outside of pgtable.c. Signed-off-by: Quentin Perret <qperret@google.com> --- arch/arm64/include/asm/kvm_pgtable.h | 20 +++++++++++++++ arch/arm64/kvm/hyp/pgtable.c | 37 ++++++++++++++++++++++++++++ 2 files changed, 57 insertions(+)