1 files changed, 79 insertions, 1 deletions

diff --git a/arch/s390/kvm/pv.c b/arch/s390/kvm/pv.c
index 75e81ba26d04..14c330ec8ceb 100644
--- a/arch/s390/kvm/pv.c
+++ b/arch/s390/kvm/pv.c
@@ -33,6 +33,64 @@ bool kvm_s390_pv_cpu_is_protected(struct kvm_vcpu *vcpu)
 EXPORT_SYMBOL_GPL(kvm_s390_pv_cpu_is_protected);
 
 /**
+ * kvm_s390_pv_make_secure() - make one guest page secure
+ * @kvm: the guest
+ * @gaddr: the guest address that needs to be made secure
+ * @uvcb: the UVCB specifying which operation needs to be performed
+ *
+ * Context: needs to be called with kvm->srcu held.
+ * Return: 0 on success, < 0 in case of error.
+ */
+int kvm_s390_pv_make_secure(struct kvm *kvm, unsigned long gaddr, void *uvcb)
+{
+	unsigned long vmaddr;
+
+	lockdep_assert_held(&kvm->srcu);
+
+	vmaddr = gfn_to_hva(kvm, gpa_to_gfn(gaddr));
+	if (kvm_is_error_hva(vmaddr))
+		return -EFAULT;
+	return make_hva_secure(kvm->mm, vmaddr, uvcb);
+}
+
+int kvm_s390_pv_convert_to_secure(struct kvm *kvm, unsigned long gaddr)
+{
+	struct uv_cb_cts uvcb = {
+		.header.cmd = UVC_CMD_CONV_TO_SEC_STOR,
+		.header.len = sizeof(uvcb),
+		.guest_handle = kvm_s390_pv_get_handle(kvm),
+		.gaddr = gaddr,
+	};
+
+	return kvm_s390_pv_make_secure(kvm, gaddr, &uvcb);
+}
+
+/**
+ * kvm_s390_pv_destroy_page() - Destroy a guest page.
+ * @kvm: the guest
+ * @gaddr: the guest address to destroy
+ *
+ * An attempt will be made to destroy the given guest page. If the attempt
+ * fails, an attempt is made to export the page. If both attempts fail, an
+ * appropriate error is returned.
+ *
+ * Context: may sleep.
+ */
+int kvm_s390_pv_destroy_page(struct kvm *kvm, unsigned long gaddr)
+{
+	struct page *page;
+	int rc = 0;
+
+	mmap_read_lock(kvm->mm);
+	page = gfn_to_page(kvm, gpa_to_gfn(gaddr));
+	if (page)
+		rc = __kvm_s390_pv_destroy_page(page);
+	kvm_release_page_clean(page);
+	mmap_read_unlock(kvm->mm);
+	return rc;
+}
+
+/**
  * struct pv_vm_to_be_destroyed - Represents a protected VM that needs to
  * be destroyed
  *
@@ -637,11 +695,29 @@ static int unpack_one(struct kvm *kvm, unsigned long addr, u64 tweak,
 		.tweak[0] = tweak,
 		.tweak[1] = offset,
 	};
-	int ret = gmap_make_secure(kvm->arch.gmap, addr, &uvcb);
+	int ret = kvm_s390_pv_make_secure(kvm, addr, &uvcb);
+	unsigned long vmaddr;
+	bool unlocked;
 
 	*rc = uvcb.header.rc;
 	*rrc = uvcb.header.rrc;
 
+	if (ret == -ENXIO) {
+		mmap_read_lock(kvm->mm);
+		vmaddr = gfn_to_hva(kvm, gpa_to_gfn(addr));
+		if (kvm_is_error_hva(vmaddr)) {
+			ret = -EFAULT;
+		} else {
+			ret = fixup_user_fault(kvm->mm, vmaddr, FAULT_FLAG_WRITE, &unlocked);
+			if (!ret)
+				ret = __gmap_link(kvm->arch.gmap, addr, vmaddr);
+		}
+		mmap_read_unlock(kvm->mm);
+		if (!ret)
+			return -EAGAIN;
+		return ret;
+	}
+
 	if (ret && ret != -EAGAIN)
 		KVM_UV_EVENT(kvm, 3, "PROTVIRT VM UNPACK: failed addr %llx with rc %x rrc %x",
 			     uvcb.gaddr, *rc, *rrc);
@@ -660,6 +736,8 @@ int kvm_s390_pv_unpack(struct kvm *kvm, unsigned long addr, unsigned long size,
 	KVM_UV_EVENT(kvm, 3, "PROTVIRT VM UNPACK: start addr %lx size %lx",
 		     addr, size);
 
+	guard(srcu)(&kvm->srcu);
+
 	while (offset < size) {
 		ret = unpack_one(kvm, addr, tweak, offset, rc, rrc);
 		if (ret == -EAGAIN) {