1 files changed, 72 insertions, 0 deletions

diff --git a/arch/s390/kvm/gaccess.c b/arch/s390/kvm/gaccess.c
index 37838f637707..d53a183c2005 100644
--- a/arch/s390/kvm/gaccess.c
+++ b/arch/s390/kvm/gaccess.c
@@ -795,6 +795,35 @@ static int low_address_protection_enabled(struct kvm_vcpu *vcpu,
 	return 1;
 }
 
+static int vm_check_access_key(struct kvm *kvm, u8 access_key,
+			       enum gacc_mode mode, gpa_t gpa)
+{
+	u8 storage_key, access_control;
+	bool fetch_protected;
+	unsigned long hva;
+	int r;
+
+	if (access_key == 0)
+		return 0;
+
+	hva = gfn_to_hva(kvm, gpa_to_gfn(gpa));
+	if (kvm_is_error_hva(hva))
+		return PGM_ADDRESSING;
+
+	mmap_read_lock(current->mm);
+	r = get_guest_storage_key(current->mm, hva, &storage_key);
+	mmap_read_unlock(current->mm);
+	if (r)
+		return r;
+	access_control = FIELD_GET(_PAGE_ACC_BITS, storage_key);
+	if (access_control == access_key)
+		return 0;
+	fetch_protected = storage_key & _PAGE_FP_BIT;
+	if ((mode == GACC_FETCH || mode == GACC_IFETCH) && !fetch_protected)
+		return 0;
+	return PGM_PROTECTION;
+}
+
 static bool fetch_prot_override_applicable(struct kvm_vcpu *vcpu, enum gacc_mode mode,
 					   union asce asce)
 {
@@ -994,6 +1023,26 @@ access_guest_page_with_key(struct kvm *kvm, enum gacc_mode mode, gpa_t gpa,
 	return 0;
 }
 
+int access_guest_abs_with_key(struct kvm *kvm, gpa_t gpa, void *data,
+			      unsigned long len, enum gacc_mode mode, u8 access_key)
+{
+	int offset = offset_in_page(gpa);
+	int fragment_len;
+	int rc;
+
+	while (min(PAGE_SIZE - offset, len) > 0) {
+		fragment_len = min(PAGE_SIZE - offset, len);
+		rc = access_guest_page_with_key(kvm, mode, gpa, data, fragment_len, access_key);
+		if (rc)
+			return rc;
+		offset = 0;
+		len -= fragment_len;
+		data += fragment_len;
+		gpa += fragment_len;
+	}
+	return 0;
+}
+
 int access_guest_with_key(struct kvm_vcpu *vcpu, unsigned long ga, u8 ar,
 			  void *data, unsigned long len, enum gacc_mode mode,
 			  u8 access_key)
@@ -1145,6 +1194,29 @@ int check_gva_range(struct kvm_vcpu *vcpu, unsigned long gva, u8 ar,
 }
 
 /**
+ * check_gpa_range - test a range of guest physical addresses for accessibility
+ * @kvm: virtual machine instance
+ * @gpa: guest physical address
+ * @length: length of test range
+ * @mode: access mode to test, relevant for storage keys
+ * @access_key: access key to mach the storage keys with
+ */
+int check_gpa_range(struct kvm *kvm, unsigned long gpa, unsigned long length,
+		    enum gacc_mode mode, u8 access_key)
+{
+	unsigned int fragment_len;
+	int rc = 0;
+
+	while (length && !rc) {
+		fragment_len = min(PAGE_SIZE - offset_in_page(gpa), length);
+		rc = vm_check_access_key(kvm, access_key, mode, gpa);
+		length -= fragment_len;
+		gpa += fragment_len;
+	}
+	return rc;
+}
+
+/**
  * kvm_s390_check_low_addr_prot_real - check for low-address protection
  * @vcpu: virtual cpu
  * @gra: Guest real address