From 2ff072ba7ad2deb1c3b2d231faa0ac3a25e2451b Mon Sep 17 00:00:00 2001 From: David Stevens Date: Thu, 10 Oct 2024 11:23:32 -0700 Subject: KVM: Migrate kvm_vcpu_map() to kvm_follow_pfn() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Migrate kvm_vcpu_map() to kvm_follow_pfn(), and have it track whether or not the map holds a refcounted struct page. Precisely tracking struct page references will eventually allow removing kvm_pfn_to_refcounted_page() and its various wrappers. Signed-off-by: David Stevens [sean: use a pointer instead of a boolean] Tested-by: Alex Bennée Signed-off-by: Sean Christopherson Tested-by: Dmitry Osipenko Signed-off-by: Paolo Bonzini Message-ID: <20241010182427.1434605-31-seanjc@google.com> --- virt/kvm/kvm_main.c | 26 ++++++++++++++++---------- 1 file changed, 16 insertions(+), 10 deletions(-) (limited to 'virt') diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 64888257e301..842a5d5f3120 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -3087,21 +3087,21 @@ struct page *gfn_to_page(struct kvm *kvm, gfn_t gfn) } EXPORT_SYMBOL_GPL(gfn_to_page); -void kvm_release_pfn(kvm_pfn_t pfn, bool dirty) -{ - if (dirty) - kvm_release_pfn_dirty(pfn); - else - kvm_release_pfn_clean(pfn); -} - int kvm_vcpu_map(struct kvm_vcpu *vcpu, gfn_t gfn, struct kvm_host_map *map) { + struct kvm_follow_pfn kfp = { + .slot = gfn_to_memslot(vcpu->kvm, gfn), + .gfn = gfn, + .flags = FOLL_WRITE, + .refcounted_page = &map->refcounted_page, + }; + + map->refcounted_page = NULL; map->page = NULL; map->hva = NULL; map->gfn = gfn; - map->pfn = gfn_to_pfn(vcpu->kvm, gfn); + map->pfn = kvm_follow_pfn(&kfp); if (is_error_noslot_pfn(map->pfn)) return -EINVAL; @@ -3133,10 +3133,16 @@ void kvm_vcpu_unmap(struct kvm_vcpu *vcpu, struct kvm_host_map *map, bool dirty) if (dirty) kvm_vcpu_mark_page_dirty(vcpu, map->gfn); - kvm_release_pfn(map->pfn, dirty); + if (map->refcounted_page) { + if (dirty) + kvm_release_page_dirty(map->refcounted_page); + else + kvm_release_page_clean(map->refcounted_page); + } map->hva = NULL; map->page = NULL; + map->refcounted_page = NULL; } EXPORT_SYMBOL_GPL(kvm_vcpu_unmap); -- cgit v1.2.3