[kvm-unit-tests PATCH v3 2/7] lib: s390x: uv: Add intercept data check library function

[Janosch Frank <frankja@xxxxxxxxxxxxx>]

When working with guests it's essential to check the SIE intercept
data for the correct values. Fortunately on PV guests these values are
constants so we can create check functions which test for the
constants.

While we're at it let's make pv-diags.c use this new function.

Signed-off-by: Janosch Frank <frankja@xxxxxxxxxxxxx>
---
 lib/s390x/pv_icptdata.h | 42 +++++++++++++++++++++++++++++++++++++++++
 s390x/pv-diags.c        | 14 ++++++--------
 2 files changed, 48 insertions(+), 8 deletions(-)
 create mode 100644 lib/s390x/pv_icptdata.h

diff --git a/lib/s390x/pv_icptdata.h b/lib/s390x/pv_icptdata.h
new file mode 100644
index 00000000..4746117e
--- /dev/null
+++ b/lib/s390x/pv_icptdata.h
@@ -0,0 +1,42 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Commonly used checks for PV SIE intercept data
+ *
+ * Copyright IBM Corp. 2023
+ * Author: Janosch Frank <frankja@xxxxxxxxxxxxx>
+ */
+
+#ifndef _S390X_PV_ICPTDATA_H_
+#define _S390X_PV_ICPTDATA_H_
+
+#include <sie.h>
+
+/*
+ * Checks the diagnose instruction intercept data for consistency with
+ * the constants defined by the PV SIE architecture
+ *
+ * Supports: 0x44, 0x9c, 0x288, 0x308, 0x500
+ */
+static bool pv_icptdata_check_diag(struct vm *vm, int diag)
+{
+	int icptcode;
+
+	switch (diag) {
+	case 0x44:
+	case 0x9c:
+	case 0x288:
+	case 0x308:
+		icptcode = ICPT_PV_NOTIFY;
+		break;
+	case 0x500:
+		icptcode = ICPT_PV_INSTR;
+		break;
+	default:
+		/* If a new diag is introduced add it to the cases above! */
+		assert(0);
+	}
+
+	return vm->sblk->icptcode == icptcode && vm->sblk->ipa == 0x8302 &&
+	       vm->sblk->ipb == 0x50000000 && vm->save_area.guest.grs[5] == diag;
+}
+#endif
diff --git a/s390x/pv-diags.c b/s390x/pv-diags.c
index 5165937a..096ac61f 100644
--- a/s390x/pv-diags.c
+++ b/s390x/pv-diags.c
@@ -9,6 +9,7 @@
  */
 #include <libcflat.h>
 #include <snippet.h>
+#include <pv_icptdata.h>
 #include <sie.h>
 #include <sclp.h>
 #include <asm/facility.h>
@@ -31,8 +32,7 @@ static void test_diag_500(void)
 			size_gbin, size_hdr, SNIPPET_UNPACK_OFF);
 
 	sie(&vm);
-	report(vm.sblk->icptcode == ICPT_PV_INSTR && vm.sblk->ipa == 0x8302 &&
-	       vm.sblk->ipb == 0x50000000 && vm.save_area.guest.grs[5] == 0x500,
+	report(pv_icptdata_check_diag(&vm, 0x500),
 	       "intercept values");
 	report(vm.save_area.guest.grs[1] == 1 &&
 	       vm.save_area.guest.grs[2] == 2 &&
@@ -45,9 +45,8 @@ static void test_diag_500(void)
 	 */
 	vm.sblk->iictl = IICTL_CODE_OPERAND;
 	sie(&vm);
-	report(vm.sblk->icptcode == ICPT_PV_NOTIFY && vm.sblk->ipa == 0x8302 &&
-	       vm.sblk->ipb == 0x50000000 && vm.save_area.guest.grs[5] == 0x9c
-	       && vm.save_area.guest.grs[0] == PGM_INT_CODE_OPERAND,
+	report(pv_icptdata_check_diag(&vm, 0x9c) &&
+	       vm.save_area.guest.grs[0] == PGM_INT_CODE_OPERAND,
 	       "operand exception");
 
 	/*
@@ -58,9 +57,8 @@ static void test_diag_500(void)
 	vm.sblk->iictl = IICTL_CODE_SPECIFICATION;
 	/* Inject PGM, next exit should be 9c */
 	sie(&vm);
-	report(vm.sblk->icptcode == ICPT_PV_NOTIFY && vm.sblk->ipa == 0x8302 &&
-	       vm.sblk->ipb == 0x50000000 && vm.save_area.guest.grs[5] == 0x9c
-	       && vm.save_area.guest.grs[0] == PGM_INT_CODE_SPECIFICATION,
+	report(pv_icptdata_check_diag(&vm, 0x9c) &&
+	       vm.save_area.guest.grs[0] == PGM_INT_CODE_SPECIFICATION,
 	       "specification exception");
 
 	/* No need for cleanup, just tear down the VM */
-- 
2.34.1