KVM: pfncache: add a mark-dirty helper

At the moment pages are marked dirty by open-coded calls to
mark_page_dirty_in_slot(), directly deferefencing the gpa and memslot
from the cache. After a subsequent patch these may not always be set
so add a helper now so that caller will protected from the need to know
about this detail.

Signed-off-by: Paul Durrant <pdurrant@amazon.com>
Reviewed-by: David Woodhouse <dwmw@amazon.co.uk>
---
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Sean Christopherson <seanjc@google.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: x86@kernel.org
v8:
 - Make the helper a static inline.

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 2c924075f6f112a594c0a4390bb7dcc2d7e8fabf..f4ebac198ff5c66d715d5b759daec50e230f35fa 100644 (file)
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -3145,7 +3145,7 @@ static void kvm_setup_guest_pvclock(struct kvm_vcpu *v,
 
        guest_hv_clock->version = ++vcpu->hv_clock.version;
 
-       mark_page_dirty_in_slot(v->kvm, gpc->memslot, gpc->gpa >> PAGE_SHIFT);
+       kvm_gpc_mark_dirty(gpc);
        read_unlock_irqrestore(&gpc->lock, flags);
 
        trace_kvm_pvclock_update(v->vcpu_id, &vcpu->hv_clock);

diff --git a/arch/x86/kvm/xen.c b/arch/x86/kvm/xen.c
index 426306022c2fad7e63c0dfe317e40ab7a094374a..41a7c03f7204c57e1640d0f9b9e8a40ec93f21bc 100644 (file)
--- a/arch/x86/kvm/xen.c
+++ b/arch/x86/kvm/xen.c
@@ -453,11 +453,11 @@ static void kvm_xen_update_runstate_guest(struct kvm_vcpu *v, bool atomic)
        }
 
        if (user_len2) {
-               mark_page_dirty_in_slot(v->kvm, gpc2->memslot, gpc2->gpa >> PAGE_SHIFT);
+               kvm_gpc_mark_dirty(gpc2);
                read_unlock(&gpc2->lock);
        }
 
-       mark_page_dirty_in_slot(v->kvm, gpc1->memslot, gpc1->gpa >> PAGE_SHIFT);
+       kvm_gpc_mark_dirty(gpc1);
        read_unlock_irqrestore(&gpc1->lock, flags);
 }
 
@@ -565,7 +565,7 @@ void kvm_xen_inject_pending_events(struct kvm_vcpu *v)
                WRITE_ONCE(vi->evtchn_upcall_pending, 1);
        }
 
-       mark_page_dirty_in_slot(v->kvm, gpc->memslot, gpc->gpa >> PAGE_SHIFT);
+       kvm_gpc_mark_dirty(gpc);
        read_unlock_irqrestore(&gpc->lock, flags);
 
        /* For the per-vCPU lapic vector, deliver it as MSI. */

diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index fb6c6109fdcad69f81cd38edf52dce7dc3d7a4e9..a4e52ad453b696fd4967cf5b61c184f662531233 100644 (file)
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -1367,6 +1367,17 @@ int kvm_gpc_refresh(struct gfn_to_pfn_cache *gpc, unsigned long len);
  */
 void kvm_gpc_deactivate(struct gfn_to_pfn_cache *gpc);
 
+/**
+ * kvm_gpc_mark_dirty - mark a cached page as dirty.
+ *
+ * @gpc:          struct gfn_to_pfn_cache object.
+ */
+static inline void kvm_gpc_mark_dirty(struct gfn_to_pfn_cache *gpc)
+{
+       lockdep_assert_held(&gpc->lock);
+       mark_page_dirty_in_slot(gpc->kvm, gpc->memslot, gpc->gpa >> PAGE_SHIFT);
+}
+
 void kvm_sigset_activate(struct kvm_vcpu *vcpu);
 void kvm_sigset_deactivate(struct kvm_vcpu *vcpu);