Hi, On Fri, Apr 12, 2024 at 9:43 AM Steven Price <steven.price@xxxxxxx> wrote: > > From: Sean Christopherson <seanjc@xxxxxxxxxx> > > Add flags to "struct kvm_gfn_range" to let notifier events target only > shared and only private mappings, and write up the existing mmu_notifier > events to be shared-only (private memory is never associated with a > userspace virtual address, i.e. can't be reached via mmu_notifiers). > > Add two flags so that KVM can handle the three possibilities (shared, > private, and shared+private) without needing something like a tri-state > enum. > > Link: https://lore.kernel.org/all/ZJX0hk+KpQP0KUyB@xxxxxxxxxx > Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx> > Signed-off-by: Steven Price <steven.price@xxxxxxx> > --- > include/linux/kvm_host.h | 2 ++ > virt/kvm/kvm_main.c | 7 +++++++ > 2 files changed, 9 insertions(+) > > diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h > index 48f31dcd318a..c7581360fd88 100644 > --- a/include/linux/kvm_host.h > +++ b/include/linux/kvm_host.h > @@ -268,6 +268,8 @@ struct kvm_gfn_range { > gfn_t start; > gfn_t end; > union kvm_mmu_notifier_arg arg; > + bool only_private; > + bool only_shared; > bool may_block; > }; > bool kvm_unmap_gfn_range(struct kvm *kvm, struct kvm_gfn_range *range); > diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c > index fb49c2a60200..3486ceef6f4e 100644 > --- a/virt/kvm/kvm_main.c > +++ b/virt/kvm/kvm_main.c > @@ -633,6 +633,13 @@ static __always_inline kvm_mn_ret_t __kvm_handle_hva_range(struct kvm *kvm, > * the second or later invocation of the handler). > */ > gfn_range.arg = range->arg; > + > + /* > + * HVA-based notifications aren't relevant to private > + * mappings as they don't have a userspace mapping. > + */ > + gfn_range.only_private = false; > + gfn_range.only_shared = true; > gfn_range.may_block = range->may_block; I'd discussed this with Sean when he posted this earlier. Having two booleans to encode three valid states could be confusing. In response, Sean suggested using an enum instead: https://lore.kernel.org/all/ZUO1Giju0GkUdF0o@xxxxxxxxxx/ Cheers, /fuad > > /* > -- > 2.34.1 >
