[PATCH 5/8] KVM: Add hva_to_memslot

[Alexander Graf <agraf@suse.de>]

Architecture code might want to figure out if an hva that it gets for example
via the mmu notifier callbacks actually is in guest mapped memory, and if so,
in which memory slot.

This patch introduces a helper function to enable it to do so. It is a
prerequisite for the e500 mmu notifier implementation.

Signed-off-by: Alexander Graf <agraf@suse.de>
---
 include/linux/kvm_host.h |    1 +
 virt/kvm/kvm_main.c      |   14 ++++++++++++++
 2 files changed, 15 insertions(+), 0 deletions(-)

diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index dbc65f9..2b92928 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -464,6 +464,7 @@ int kvm_gfn_to_hva_cache_init(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
 int kvm_clear_guest_page(struct kvm *kvm, gfn_t gfn, int offset, int len);
 int kvm_clear_guest(struct kvm *kvm, gpa_t gpa, unsigned long len);
 struct kvm_memory_slot *gfn_to_memslot(struct kvm *kvm, gfn_t gfn);
+struct kvm_memory_slot *hva_to_memslot(struct kvm *kvm, hva_t hva);
 int kvm_is_visible_gfn(struct kvm *kvm, gfn_t gfn);
 unsigned long kvm_host_page_size(struct kvm *kvm, gfn_t gfn);
 void mark_page_dirty(struct kvm *kvm, gfn_t gfn);
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index bcf973e..d42591d 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -999,6 +999,20 @@ struct kvm_memory_slot *gfn_to_memslot(struct kvm *kvm, gfn_t gfn)
 }
 EXPORT_SYMBOL_GPL(gfn_to_memslot);
 
+struct kvm_memory_slot *hva_to_memslot(struct kvm *kvm, hva_t hva)
+{
+	struct kvm_memslots *slots = kvm_memslots(kvm);
+	struct kvm_memory_slot *memslot;
+
+	kvm_for_each_memslot(memslot, slots)
+		if (hva >= memslot->userspace_addr &&
+		      hva < memslot->userspace_addr + memslot->npages)
+			return memslot;
+
+	return NULL;
+}
+EXPORT_SYMBOL_GPL(hva_to_memslot);
+
 int kvm_is_visible_gfn(struct kvm *kvm, gfn_t gfn)
 {
 	struct kvm_memory_slot *memslot = gfn_to_memslot(kvm, gfn);
-- 
1.6.0.2