1 files changed, 177 insertions, 13 deletions

diff --git a/arch/powerpc/kvm/book3s_hv_nested.c b/arch/powerpc/kvm/book3s_hv_nested.c
index 401d2ecbebc5..735e0ac6f5b2 100644
--- a/arch/powerpc/kvm/book3s_hv_nested.c
+++ b/arch/powerpc/kvm/book3s_hv_nested.c
@@ -195,6 +195,26 @@ void kvmhv_restore_hv_return_state(struct kvm_vcpu *vcpu,
 	vcpu->arch.ppr = hr->ppr;
 }
 
+static void kvmhv_nested_mmio_needed(struct kvm_vcpu *vcpu, u64 regs_ptr)
+{
+	/* No need to reflect the page fault to L1, we've handled it */
+	vcpu->arch.trap = 0;
+
+	/*
+	 * Since the L2 gprs have already been written back into L1 memory when
+	 * we complete the mmio, store the L1 memory location of the L2 gpr
+	 * being loaded into by the mmio so that the loaded value can be
+	 * written there in kvmppc_complete_mmio_load()
+	 */
+	if (((vcpu->arch.io_gpr & KVM_MMIO_REG_EXT_MASK) == KVM_MMIO_REG_GPR)
+	    && (vcpu->mmio_is_write == 0)) {
+		vcpu->arch.nested_io_gpr = (gpa_t) regs_ptr +
+					   offsetof(struct pt_regs,
+						    gpr[vcpu->arch.io_gpr]);
+		vcpu->arch.io_gpr = KVM_MMIO_REG_NESTED_GPR;
+	}
+}
+
 long kvmhv_enter_nested_guest(struct kvm_vcpu *vcpu)
 {
 	long int err, r;
@@ -316,6 +336,11 @@ long kvmhv_enter_nested_guest(struct kvm_vcpu *vcpu)
 	if (r == -EINTR)
 		return H_INTERRUPT;
 
+	if (vcpu->mmio_needed) {
+		kvmhv_nested_mmio_needed(vcpu, regs_ptr);
+		return H_TOO_HARD;
+	}
+
 	return vcpu->arch.trap;
 }
 
@@ -437,6 +462,81 @@ long kvmhv_set_partition_table(struct kvm_vcpu *vcpu)
 }
 
 /*
+ * Handle the H_COPY_TOFROM_GUEST hcall.
+ * r4 = L1 lpid of nested guest
+ * r5 = pid
+ * r6 = eaddr to access
+ * r7 = to buffer (L1 gpa)
+ * r8 = from buffer (L1 gpa)
+ * r9 = n bytes to copy
+ */
+long kvmhv_copy_tofrom_guest_nested(struct kvm_vcpu *vcpu)
+{
+	struct kvm_nested_guest *gp;
+	int l1_lpid = kvmppc_get_gpr(vcpu, 4);
+	int pid = kvmppc_get_gpr(vcpu, 5);
+	gva_t eaddr = kvmppc_get_gpr(vcpu, 6);
+	gpa_t gp_to = (gpa_t) kvmppc_get_gpr(vcpu, 7);
+	gpa_t gp_from = (gpa_t) kvmppc_get_gpr(vcpu, 8);
+	void *buf;
+	unsigned long n = kvmppc_get_gpr(vcpu, 9);
+	bool is_load = !!gp_to;
+	long rc;
+
+	if (gp_to && gp_from) /* One must be NULL to determine the direction */
+		return H_PARAMETER;
+
+	if (eaddr & (0xFFFUL << 52))
+		return H_PARAMETER;
+
+	buf = kzalloc(n, GFP_KERNEL);
+	if (!buf)
+		return H_NO_MEM;
+
+	gp = kvmhv_get_nested(vcpu->kvm, l1_lpid, false);
+	if (!gp) {
+		rc = H_PARAMETER;
+		goto out_free;
+	}
+
+	mutex_lock(&gp->tlb_lock);
+
+	if (is_load) {
+		/* Load from the nested guest into our buffer */
+		rc = __kvmhv_copy_tofrom_guest_radix(gp->shadow_lpid, pid,
+						     eaddr, buf, NULL, n);
+		if (rc)
+			goto not_found;
+
+		/* Write what was loaded into our buffer back to the L1 guest */
+		rc = kvm_vcpu_write_guest(vcpu, gp_to, buf, n);
+		if (rc)
+			goto not_found;
+	} else {
+		/* Load the data to be stored from the L1 guest into our buf */
+		rc = kvm_vcpu_read_guest(vcpu, gp_from, buf, n);
+		if (rc)
+			goto not_found;
+
+		/* Store from our buffer into the nested guest */
+		rc = __kvmhv_copy_tofrom_guest_radix(gp->shadow_lpid, pid,
+						     eaddr, NULL, buf, n);
+		if (rc)
+			goto not_found;
+	}
+
+out_unlock:
+	mutex_unlock(&gp->tlb_lock);
+	kvmhv_put_nested(gp);
+out_free:
+	kfree(buf);
+	return rc;
+not_found:
+	rc = H_NOT_FOUND;
+	goto out_unlock;
+}
+
+/*
  * Reload the partition table entry for a guest.
  * Caller must hold gp->tlb_lock.
  */
@@ -480,6 +580,7 @@ struct kvm_nested_guest *kvmhv_alloc_nested(struct kvm *kvm, unsigned int lpid)
 	if (shadow_lpid < 0)
 		goto out_free2;
 	gp->shadow_lpid = shadow_lpid;
+	gp->radix = 1;
 
 	memset(gp->prev_cpu, -1, sizeof(gp->prev_cpu));
 
@@ -687,6 +788,57 @@ void kvmhv_insert_nest_rmap(struct kvm *kvm, unsigned long *rmapp,
 	*n_rmap = NULL;
 }
 
+static void kvmhv_update_nest_rmap_rc(struct kvm *kvm, u64 n_rmap,
+				      unsigned long clr, unsigned long set,
+				      unsigned long hpa, unsigned long mask)
+{
+	struct kvm_nested_guest *gp;
+	unsigned long gpa;
+	unsigned int shift, lpid;
+	pte_t *ptep;
+
+	gpa = n_rmap & RMAP_NESTED_GPA_MASK;
+	lpid = (n_rmap & RMAP_NESTED_LPID_MASK) >> RMAP_NESTED_LPID_SHIFT;
+	gp = kvmhv_find_nested(kvm, lpid);
+	if (!gp)
+		return;
+
+	/* Find the pte */
+	ptep = __find_linux_pte(gp->shadow_pgtable, gpa, NULL, &shift);
+	/*
+	 * If the pte is present and the pfn is still the same, update the pte.
+	 * If the pfn has changed then this is a stale rmap entry, the nested
+	 * gpa actually points somewhere else now, and there is nothing to do.
+	 * XXX A future optimisation would be to remove the rmap entry here.
+	 */
+	if (ptep && pte_present(*ptep) && ((pte_val(*ptep) & mask) == hpa)) {
+		__radix_pte_update(ptep, clr, set);
+		kvmppc_radix_tlbie_page(kvm, gpa, shift, lpid);
+	}
+}
+
+/*
+ * For a given list of rmap entries, update the rc bits in all ptes in shadow
+ * page tables for nested guests which are referenced by the rmap list.
+ */
+void kvmhv_update_nest_rmap_rc_list(struct kvm *kvm, unsigned long *rmapp,
+				    unsigned long clr, unsigned long set,
+				    unsigned long hpa, unsigned long nbytes)
+{
+	struct llist_node *entry = ((struct llist_head *) rmapp)->first;
+	struct rmap_nested *cursor;
+	unsigned long rmap, mask;
+
+	if ((clr | set) & ~(_PAGE_DIRTY | _PAGE_ACCESSED))
+		return;
+
+	mask = PTE_RPN_MASK & ~(nbytes - 1);
+	hpa &= mask;
+
+	for_each_nest_rmap_safe(cursor, entry, &rmap)
+		kvmhv_update_nest_rmap_rc(kvm, rmap, clr, set, hpa, mask);
+}
+
 static void kvmhv_remove_nest_rmap(struct kvm *kvm, u64 n_rmap,
 				   unsigned long hpa, unsigned long mask)
 {
@@ -723,7 +875,7 @@ static void kvmhv_remove_nest_rmap_list(struct kvm *kvm, unsigned long *rmapp,
 
 /* called with kvm->mmu_lock held */
 void kvmhv_remove_nest_rmap_range(struct kvm *kvm,
-				  struct kvm_memory_slot *memslot,
+				  const struct kvm_memory_slot *memslot,
 				  unsigned long gpa, unsigned long hpa,
 				  unsigned long nbytes)
 {
@@ -1049,7 +1201,7 @@ static long kvmhv_handle_nested_set_rc(struct kvm_vcpu *vcpu,
 	struct kvm *kvm = vcpu->kvm;
 	bool writing = !!(dsisr & DSISR_ISSTORE);
 	u64 pgflags;
-	bool ret;
+	long ret;
 
 	/* Are the rc bits set in the L1 partition scoped pte? */
 	pgflags = _PAGE_ACCESSED;
@@ -1062,16 +1214,22 @@ static long kvmhv_handle_nested_set_rc(struct kvm_vcpu *vcpu,
 	/* Set the rc bit in the pte of our (L0) pgtable for the L1 guest */
 	ret = kvmppc_hv_handle_set_rc(kvm, kvm->arch.pgtable, writing,
 				     gpte.raddr, kvm->arch.lpid);
-	spin_unlock(&kvm->mmu_lock);
-	if (!ret)
-		return -EINVAL;
+	if (!ret) {
+		ret = -EINVAL;
+		goto out_unlock;
+	}
 
 	/* Set the rc bit in the pte of the shadow_pgtable for the nest guest */
 	ret = kvmppc_hv_handle_set_rc(kvm, gp->shadow_pgtable, writing, n_gpa,
 				      gp->shadow_lpid);
 	if (!ret)
-		return -EINVAL;
-	return 0;
+		ret = -EINVAL;
+	else
+		ret = 0;
+
+out_unlock:
+	spin_unlock(&kvm->mmu_lock);
+	return ret;
 }
 
 static inline int kvmppc_radix_level_to_shift(int level)
@@ -1099,7 +1257,8 @@ static inline int kvmppc_radix_shift_to_level(int shift)
 }
 
 /* called with gp->tlb_lock held */
-static long int __kvmhv_nested_page_fault(struct kvm_vcpu *vcpu,
+static long int __kvmhv_nested_page_fault(struct kvm_run *run,
+					  struct kvm_vcpu *vcpu,
 					  struct kvm_nested_guest *gp)
 {
 	struct kvm *kvm = vcpu->kvm;
@@ -1180,9 +1339,9 @@ static long int __kvmhv_nested_page_fault(struct kvm_vcpu *vcpu,
 			kvmppc_core_queue_data_storage(vcpu, ea, dsisr);
 			return RESUME_GUEST;
 		}
-		/* passthrough of emulated MMIO case... */
-		pr_err("emulated MMIO passthrough?\n");
-		return -EINVAL;
+
+		/* passthrough of emulated MMIO case */
+		return kvmppc_hv_emulate_mmio(run, vcpu, gpa, ea, writing);
 	}
 	if (memslot->flags & KVM_MEM_READONLY) {
 		if (writing) {
@@ -1220,6 +1379,8 @@ static long int __kvmhv_nested_page_fault(struct kvm_vcpu *vcpu,
 			return ret;
 		shift = kvmppc_radix_level_to_shift(level);
 	}
+	/* Align gfn to the start of the page */
+	gfn = (gpa & ~((1UL << shift) - 1)) >> PAGE_SHIFT;
 
 	/* 3. Compute the pte we need to insert for nest_gpa -> host r_addr */
 
@@ -1227,6 +1388,9 @@ static long int __kvmhv_nested_page_fault(struct kvm_vcpu *vcpu,
 	perm |= gpte.may_read ? 0UL : _PAGE_READ;
 	perm |= gpte.may_write ? 0UL : _PAGE_WRITE;
 	perm |= gpte.may_execute ? 0UL : _PAGE_EXEC;
+	/* Only set accessed/dirty (rc) bits if set in host and l1 guest ptes */
+	perm |= (gpte.rc & _PAGE_ACCESSED) ? 0UL : _PAGE_ACCESSED;
+	perm |= ((gpte.rc & _PAGE_DIRTY) && writing) ? 0UL : _PAGE_DIRTY;
 	pte = __pte(pte_val(pte) & ~perm);
 
 	/* What size pte can we insert? */
@@ -1264,13 +1428,13 @@ static long int __kvmhv_nested_page_fault(struct kvm_vcpu *vcpu,
 	return RESUME_GUEST;
 }
 
-long int kvmhv_nested_page_fault(struct kvm_vcpu *vcpu)
+long int kvmhv_nested_page_fault(struct kvm_run *run, struct kvm_vcpu *vcpu)
 {
 	struct kvm_nested_guest *gp = vcpu->arch.nested;
 	long int ret;
 
 	mutex_lock(&gp->tlb_lock);
-	ret = __kvmhv_nested_page_fault(vcpu, gp);
+	ret = __kvmhv_nested_page_fault(run, vcpu, gp);
 	mutex_unlock(&gp->tlb_lock);
 	return ret;
 }