KVM: introduce gfn_to_pfn_memslot

Which takes a memslot pointer instead of using kvm->memslots.

To be used by SRCU convertion later.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>

2 files changed, 27 insertions, 8 deletions

diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 3c44687b3425..f1f78deece10 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -273,6 +273,8 @@ void kvm_set_page_dirty(struct page *page);
 void kvm_set_page_accessed(struct page *page);
 
 pfn_t gfn_to_pfn(struct kvm *kvm, gfn_t gfn);
+pfn_t gfn_to_pfn_memslot(struct kvm *kvm,
+                         struct kvm_memory_slot *slot, gfn_t gfn);
 void kvm_release_pfn_dirty(pfn_t);
 void kvm_release_pfn_clean(pfn_t pfn);
 void kvm_set_pfn_dirty(pfn_t pfn);
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index c9f6cfe83120..4e2321c733f7 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -835,21 +835,14 @@ unsigned long gfn_to_hva(struct kvm *kvm, gfn_t gfn)
 }
 EXPORT_SYMBOL_GPL(gfn_to_hva);
 
-pfn_t gfn_to_pfn(struct kvm *kvm, gfn_t gfn)
+static pfn_t hva_to_pfn(struct kvm *kvm, unsigned long addr)
 {
         struct page *page[1];
-        unsigned long addr;
         int npages;
         pfn_t pfn;
 
         might_sleep();
 
-        addr = gfn_to_hva(kvm, gfn);
-        if (kvm_is_error_hva(addr)) {
-                get_page(bad_page);
-                return page_to_pfn(bad_page);
-        }
-
         npages = get_user_pages_fast(addr, 1, 1, page);
 
         if (unlikely(npages != 1)) {
@@ -874,8 +867,32 @@ pfn_t gfn_to_pfn(struct kvm *kvm, gfn_t gfn)
         return pfn;
 }
 
+pfn_t gfn_to_pfn(struct kvm *kvm, gfn_t gfn)
+{
+        unsigned long addr;
+
+        addr = gfn_to_hva(kvm, gfn);
+        if (kvm_is_error_hva(addr)) {
+                get_page(bad_page);
+                return page_to_pfn(bad_page);
+        }
+
+        return hva_to_pfn(kvm, addr);
+}
 EXPORT_SYMBOL_GPL(gfn_to_pfn);
 
+static unsigned long gfn_to_hva_memslot(struct kvm_memory_slot *slot, gfn_t gfn)
+{
+        return (slot->userspace_addr + (gfn - slot->base_gfn) * PAGE_SIZE);
+}
+
+pfn_t gfn_to_pfn_memslot(struct kvm *kvm,
+                         struct kvm_memory_slot *slot, gfn_t gfn)
+{
+        unsigned long addr = gfn_to_hva_memslot(slot, gfn);
+        return hva_to_pfn(kvm, addr);
+}
+
 struct page *gfn_to_page(struct kvm *kvm, gfn_t gfn)
 {
         pfn_t pfn;