Hi Kai, "Huang, Kai" <[email protected]> writes:
> On 5/6/2017 7:25 AM, Bandan Das wrote: >> When KVM updates accessed/dirty bits, this hook can be used >> to invoke an arch specific function that implements/emulates >> dirty logging such as PML. >> >> Signed-off-by: Bandan Das <[email protected]> >> --- >> arch/x86/include/asm/kvm_host.h | 2 ++ >> arch/x86/kvm/mmu.c | 15 +++++++++++++++ >> arch/x86/kvm/mmu.h | 1 + >> arch/x86/kvm/paging_tmpl.h | 4 ++++ >> 4 files changed, 22 insertions(+) >> >> diff --git a/arch/x86/include/asm/kvm_host.h >> b/arch/x86/include/asm/kvm_host.h >> index f5bddf92..9c761fe 100644 >> --- a/arch/x86/include/asm/kvm_host.h >> +++ b/arch/x86/include/asm/kvm_host.h >> @@ -1020,6 +1020,8 @@ struct kvm_x86_ops { >> void (*enable_log_dirty_pt_masked)(struct kvm *kvm, >> struct kvm_memory_slot *slot, >> gfn_t offset, unsigned long mask); >> + int (*write_log_dirty)(struct kvm_vcpu *vcpu); > > Hi, > > Thanks for adding PML to nested support! > > IMHO this callback is only used for write L2's dirty gpa to L1's PML > buffer, so probably it's better to change the name to something like: > nested_write_log_dirty. The name was meant more to signify what it does: i.e. write dirty log rather than where in the hierarchy it's being used :) But I guess, a nested_ prefix doesn't hurt either. Bandan > Thanks, > -Kai > >> + >> /* pmu operations of sub-arch */ >> const struct kvm_pmu_ops *pmu_ops; >> >> diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c >> index 5586765..5d3376f 100644 >> --- a/arch/x86/kvm/mmu.c >> +++ b/arch/x86/kvm/mmu.c >> @@ -1498,6 +1498,21 @@ void kvm_arch_mmu_enable_log_dirty_pt_masked(struct >> kvm *kvm, >> kvm_mmu_write_protect_pt_masked(kvm, slot, gfn_offset, mask); >> } >> >> +/** >> + * kvm_arch_write_log_dirty - emulate dirty page logging >> + * @vcpu: Guest mode vcpu >> + * >> + * Emulate arch specific page modification logging for the >> + * nested hypervisor >> + */ >> +int kvm_arch_write_log_dirty(struct kvm_vcpu *vcpu) >> +{ >> + if (kvm_x86_ops->write_log_dirty) >> + return kvm_x86_ops->write_log_dirty(vcpu); >> + >> + return 0; >> +} > > kvm_nested_arch_write_log_dirty? > >> + >> bool kvm_mmu_slot_gfn_write_protect(struct kvm *kvm, >> struct kvm_memory_slot *slot, u64 gfn) >> { >> diff --git a/arch/x86/kvm/mmu.h b/arch/x86/kvm/mmu.h >> index d8ccb32..2797580 100644 >> --- a/arch/x86/kvm/mmu.h >> +++ b/arch/x86/kvm/mmu.h >> @@ -202,4 +202,5 @@ void kvm_mmu_gfn_disallow_lpage(struct kvm_memory_slot >> *slot, gfn_t gfn); >> void kvm_mmu_gfn_allow_lpage(struct kvm_memory_slot *slot, gfn_t gfn); >> bool kvm_mmu_slot_gfn_write_protect(struct kvm *kvm, >> struct kvm_memory_slot *slot, u64 gfn); >> +int kvm_arch_write_log_dirty(struct kvm_vcpu *vcpu); >> #endif >> diff --git a/arch/x86/kvm/paging_tmpl.h b/arch/x86/kvm/paging_tmpl.h >> index 314d207..5624174 100644 >> --- a/arch/x86/kvm/paging_tmpl.h >> +++ b/arch/x86/kvm/paging_tmpl.h >> @@ -226,6 +226,10 @@ static int FNAME(update_accessed_dirty_bits)(struct >> kvm_vcpu *vcpu, >> if (level == walker->level && write_fault && >> !(pte & PT_GUEST_DIRTY_MASK)) { >> trace_kvm_mmu_set_dirty_bit(table_gfn, index, >> sizeof(pte)); >> +#if PTTYPE == PTTYPE_EPT >> + if (kvm_arch_write_log_dirty(vcpu)) >> + return -EINVAL; >> +#endif >> pte |= PT_GUEST_DIRTY_MASK; >> } >> if (pte == orig_pte) >>
