6 files changed, 80 insertions, 21 deletions

diff --git a/arch/powerpc/include/asm/kvm_book3s.h b/arch/powerpc/include/asm/kvm_book3s.h
index bc81842ea25a..c55f7e6affaa 100644
--- a/arch/powerpc/include/asm/kvm_book3s.h
+++ b/arch/powerpc/include/asm/kvm_book3s.h
@@ -156,7 +156,8 @@ void kvmppc_clear_ref_hpte(struct kvm *kvm, unsigned long *hptep,
                         unsigned long pte_index);
 extern void *kvmppc_pin_guest_page(struct kvm *kvm, unsigned long addr,
                         unsigned long *nb_ret);
-extern void kvmppc_unpin_guest_page(struct kvm *kvm, void *addr);
+extern void kvmppc_unpin_guest_page(struct kvm *kvm, void *addr,
+                        unsigned long gpa, bool dirty);
 extern long kvmppc_virtmode_h_enter(struct kvm_vcpu *vcpu, unsigned long flags,
                         long pte_index, unsigned long pteh, unsigned long ptel);
 extern long kvmppc_do_h_enter(struct kvm *kvm, unsigned long flags,
diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h
index 8a48e686a755..1443768a6588 100644
--- a/arch/powerpc/include/asm/kvm_host.h
+++ b/arch/powerpc/include/asm/kvm_host.h
@@ -301,11 +301,13 @@ struct kvmppc_vcore {
  * that a guest can register.
  */
 struct kvmppc_vpa {
+        unsigned long gpa;      /* Current guest phys addr */
         void *pinned_addr;      /* Address in kernel linear mapping */
         void *pinned_end;       /* End of region */
         unsigned long next_gpa; /* Guest phys addr for update */
         unsigned long len;      /* Number of bytes required */
         u8 update_pending;      /* 1 => update pinned_addr from next_gpa */
+        bool dirty;             /* true => area has been modified by kernel */
 };
 
 struct kvmppc_pte {
diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c
index d87c90886c75..dbfd5498f440 100644
--- a/arch/powerpc/kernel/asm-offsets.c
+++ b/arch/powerpc/kernel/asm-offsets.c
@@ -477,6 +477,7 @@ int main(void)
         DEFINE(VCPU_DSISR, offsetof(struct kvm_vcpu, arch.shregs.dsisr));
         DEFINE(VCPU_DAR, offsetof(struct kvm_vcpu, arch.shregs.dar));
         DEFINE(VCPU_VPA, offsetof(struct kvm_vcpu, arch.vpa.pinned_addr));
+        DEFINE(VCPU_VPA_DIRTY, offsetof(struct kvm_vcpu, arch.vpa.dirty));
 #endif
 #ifdef CONFIG_PPC_BOOK3S
         DEFINE(VCPU_VCPUID, offsetof(struct kvm_vcpu, vcpu_id));
diff --git a/arch/powerpc/kvm/book3s_64_mmu_hv.c b/arch/powerpc/kvm/book3s_64_mmu_hv.c
index d641a6634b02..69efe0d6cedc 100644
--- a/arch/powerpc/kvm/book3s_64_mmu_hv.c
+++ b/arch/powerpc/kvm/book3s_64_mmu_hv.c
@@ -1099,11 +1099,30 @@ static int kvm_test_clear_dirty(struct kvm *kvm, unsigned long *rmapp)
         return ret;
 }
 
+static void harvest_vpa_dirty(struct kvmppc_vpa *vpa,
+                              struct kvm_memory_slot *memslot,
+                              unsigned long *map)
+{
+        unsigned long gfn;
+
+        if (!vpa->dirty || !vpa->pinned_addr)
+                return;
+        gfn = vpa->gpa >> PAGE_SHIFT;
+        if (gfn < memslot->base_gfn ||
+            gfn >= memslot->base_gfn + memslot->npages)
+                return;
+
+        vpa->dirty = false;
+        if (map)
+                __set_bit_le(gfn - memslot->base_gfn, map);
+}
+
 long kvmppc_hv_get_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot,
                              unsigned long *map)
 {
         unsigned long i;
         unsigned long *rmapp;
+        struct kvm_vcpu *vcpu;
 
         preempt_disable();
         rmapp = memslot->arch.rmap;
@@ -1112,6 +1131,15 @@ long kvmppc_hv_get_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot,
                         __set_bit_le(i, map);
                 ++rmapp;
         }
+
+        /* Harvest dirty bits from VPA and DTL updates */
+        /* Note: we never modify the SLB shadow buffer areas */
+        kvm_for_each_vcpu(i, vcpu, kvm) {
+                spin_lock(&vcpu->arch.vpa_update_lock);
+                harvest_vpa_dirty(&vcpu->arch.vpa, memslot, map);
+                harvest_vpa_dirty(&vcpu->arch.dtl, memslot, map);
+                spin_unlock(&vcpu->arch.vpa_update_lock);
+        }
         preempt_enable();
         return 0;
 }
@@ -1123,7 +1151,7 @@ void *kvmppc_pin_guest_page(struct kvm *kvm, unsigned long gpa,
         unsigned long gfn = gpa >> PAGE_SHIFT;
         struct page *page, *pages[1];
         int npages;
-        unsigned long hva, psize, offset;
+        unsigned long hva, offset;
         unsigned long pa;
         unsigned long *physp;
         int srcu_idx;
@@ -1155,14 +1183,9 @@ void *kvmppc_pin_guest_page(struct kvm *kvm, unsigned long gpa,
         }
         srcu_read_unlock(&kvm->srcu, srcu_idx);
 
-        psize = PAGE_SIZE;
-        if (PageHuge(page)) {
-                page = compound_head(page);
-                psize <<= compound_order(page);
-        }
-        offset = gpa & (psize - 1);
+        offset = gpa & (PAGE_SIZE - 1);
         if (nb_ret)
-                *nb_ret = psize - offset;
+                *nb_ret = PAGE_SIZE - offset;
         return page_address(page) + offset;
 
  err:
@@ -1170,11 +1193,31 @@ void *kvmppc_pin_guest_page(struct kvm *kvm, unsigned long gpa,
         return NULL;
 }
 
-void kvmppc_unpin_guest_page(struct kvm *kvm, void *va)
+void kvmppc_unpin_guest_page(struct kvm *kvm, void *va, unsigned long gpa,
+                             bool dirty)
 {
         struct page *page = virt_to_page(va);
+        struct kvm_memory_slot *memslot;
+        unsigned long gfn;
+        unsigned long *rmap;
+        int srcu_idx;
 
         put_page(page);
+
+        if (!dirty || !kvm->arch.using_mmu_notifiers)
+                return;
+
+        /* We need to mark this page dirty in the rmap chain */
+        gfn = gpa >> PAGE_SHIFT;
+        srcu_idx = srcu_read_lock(&kvm->srcu);
+        memslot = gfn_to_memslot(kvm, gfn);
+        if (memslot) {
+                rmap = &memslot->arch.rmap[gfn - memslot->base_gfn];
+                lock_rmap(rmap);
+                *rmap |= KVMPPC_RMAP_CHANGED;
+                unlock_rmap(rmap);
+        }
+        srcu_read_unlock(&kvm->srcu, srcu_idx);
 }
 
 /*
diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index 1e521baf9a7d..5af0f2979833 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -259,7 +259,7 @@ static unsigned long do_h_register_vpa(struct kvm_vcpu *vcpu,
                         len = ((struct reg_vpa *)va)->length.hword;
                 else
                         len = ((struct reg_vpa *)va)->length.word;
-                kvmppc_unpin_guest_page(kvm, va);
+                kvmppc_unpin_guest_page(kvm, va, vpa, false);
 
                 /* Check length */
                 if (len > nb || len < sizeof(struct reg_vpa))
@@ -359,13 +359,13 @@ static void kvmppc_update_vpa(struct kvm_vcpu *vcpu, struct kvmppc_vpa *vpap)
                 va = NULL;
                 nb = 0;
                 if (gpa)
-                        va = kvmppc_pin_guest_page(kvm, vpap->next_gpa, &nb);
+                        va = kvmppc_pin_guest_page(kvm, gpa, &nb);
                 spin_lock(&vcpu->arch.vpa_update_lock);
                 if (gpa == vpap->next_gpa)
                         break;
                 /* sigh... unpin that one and try again */
                 if (va)
-                        kvmppc_unpin_guest_page(kvm, va);
+                        kvmppc_unpin_guest_page(kvm, va, gpa, false);
         }
 
         vpap->update_pending = 0;
@@ -375,12 +375,15 @@ static void kvmppc_update_vpa(struct kvm_vcpu *vcpu, struct kvmppc_vpa *vpap)
                  * has changed the mappings underlying guest memory,
                  * so unregister the region.
                  */
-                kvmppc_unpin_guest_page(kvm, va);
+                kvmppc_unpin_guest_page(kvm, va, gpa, false);
                 va = NULL;
         }
         if (vpap->pinned_addr)
-                kvmppc_unpin_guest_page(kvm, vpap->pinned_addr);
+                kvmppc_unpin_guest_page(kvm, vpap->pinned_addr, vpap->gpa,
+                                        vpap->dirty);
+        vpap->gpa = gpa;
         vpap->pinned_addr = va;
+        vpap->dirty = false;
         if (va)
                 vpap->pinned_end = va + vpap->len;
 }
@@ -472,6 +475,7 @@ static void kvmppc_create_dtl_entry(struct kvm_vcpu *vcpu,
         /* order writing *dt vs. writing vpa->dtl_idx */
         smp_wmb();
         vpa->dtl_idx = ++vcpu->arch.dtl_index;
+        vcpu->arch.dtl.dirty = true;
 }
 
 int kvmppc_pseries_do_hcall(struct kvm_vcpu *vcpu)
@@ -913,15 +917,19 @@ out:
         return ERR_PTR(err);
 }
 
+static void unpin_vpa(struct kvm *kvm, struct kvmppc_vpa *vpa)
+{
+        if (vpa->pinned_addr)
+                kvmppc_unpin_guest_page(kvm, vpa->pinned_addr, vpa->gpa,
+                                        vpa->dirty);
+}
+
 void kvmppc_core_vcpu_free(struct kvm_vcpu *vcpu)
 {
         spin_lock(&vcpu->arch.vpa_update_lock);
-        if (vcpu->arch.dtl.pinned_addr)
-                kvmppc_unpin_guest_page(vcpu->kvm, vcpu->arch.dtl.pinned_addr);
-        if (vcpu->arch.slb_shadow.pinned_addr)
-                kvmppc_unpin_guest_page(vcpu->kvm, vcpu->arch.slb_shadow.pinned_addr);
-        if (vcpu->arch.vpa.pinned_addr)
-                kvmppc_unpin_guest_page(vcpu->kvm, vcpu->arch.vpa.pinned_addr);
+        unpin_vpa(vcpu->kvm, &vcpu->arch.dtl);
+        unpin_vpa(vcpu->kvm, &vcpu->arch.slb_shadow);
+        unpin_vpa(vcpu->kvm, &vcpu->arch.vpa);
         spin_unlock(&vcpu->arch.vpa_update_lock);
         kvm_vcpu_uninit(vcpu);
         kmem_cache_free(kvm_vcpu_cache, vcpu);
diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
index e33d11f1b977..0f23bb851711 100644
--- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S
+++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
@@ -260,6 +260,8 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_206)
         lwz     r5, LPPACA_YIELDCOUNT(r3)
         addi    r5, r5, 1
         stw     r5, LPPACA_YIELDCOUNT(r3)
+        li      r6, 1
+        stb     r6, VCPU_VPA_DIRTY(r4)
 25:
         /* Load up DAR and DSISR */
         ld      r5, VCPU_DAR(r4)
@@ -1018,6 +1020,8 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_206)
         lwz     r3, LPPACA_YIELDCOUNT(r8)
         addi    r3, r3, 1
         stw     r3, LPPACA_YIELDCOUNT(r8)
+        li      r3, 1
+        stb     r3, VCPU_VPA_DIRTY(r9)
 25:
         /* Save PMU registers if requested */
         /* r8 and cr0.eq are live here */