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 27e23714e9609edb952dbc744c0213f6b7514293..0a0ac91a494f7f05e473dcd3e733474047358a23 100644 (file)
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -3156,7 +3156,7 @@ 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 b63bf54bb376c58c1045826ddef6464ce75c2ac5..34c48d0029c1ee0b8c4665a7ffd4a6a39118e8d8 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 ea1523a7b83adeab8cba557afa932f9bb8dbaf85..64dd616612ed38c3da649b66ec2432938947f407 100644 (file)
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -1400,6 +1400,17 @@ 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);