From 1c7b627e930624dd64ee906df554c8f2bad628ff Mon Sep 17 00:00:00 2001 From: Sean Christopherson Date: Thu, 10 Oct 2024 11:23:45 -0700 Subject: KVM: Add kvm_faultin_pfn() to specifically service guest page faults MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Add a new dedicated API, kvm_faultin_pfn(), for servicing guest page faults, i.e. for getting pages/pfns that will be mapped into the guest via an mmu_notifier-protected KVM MMU. Keep struct kvm_follow_pfn buried in internal code, as having __kvm_faultin_pfn() take "out" params is actually cleaner for several architectures, e.g. it allows the caller to have its own "page fault" structure without having to marshal data to/from kvm_follow_pfn. Long term, common KVM would ideally provide a kvm_page_fault structure, a la x86's struct of the same name. But all architectures need to be converted to a common API before that can happen. Tested-by: Alex Bennée Signed-off-by: Sean Christopherson Tested-by: Dmitry Osipenko Signed-off-by: Paolo Bonzini Message-ID: <20241010182427.1434605-44-seanjc@google.com> --- include/linux/kvm_host.h | 12 ++++++++++++ 1 file changed, 12 insertions(+) (limited to 'include/linux') diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 8d35a36e7707..a63b0325d3e2 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -1231,6 +1231,18 @@ static inline void kvm_release_page_unused(struct page *page) void kvm_release_page_clean(struct page *page); void kvm_release_page_dirty(struct page *page); +kvm_pfn_t __kvm_faultin_pfn(const struct kvm_memory_slot *slot, gfn_t gfn, + unsigned int foll, bool *writable, + struct page **refcounted_page); + +static inline kvm_pfn_t kvm_faultin_pfn(struct kvm_vcpu *vcpu, gfn_t gfn, + bool write, bool *writable, + struct page **refcounted_page) +{ + return __kvm_faultin_pfn(kvm_vcpu_gfn_to_memslot(vcpu, gfn), gfn, + write ? FOLL_WRITE : 0, writable, refcounted_page); +} + kvm_pfn_t gfn_to_pfn(struct kvm *kvm, gfn_t gfn); kvm_pfn_t gfn_to_pfn_prot(struct kvm *kvm, gfn_t gfn, bool write_fault, bool *writable); -- cgit v1.2.3