[kvm-unit-tests PATCH v5 1/3] s390x: Test TEID values in storage key test

[Janis Schoetterl-Glausch <scgl@xxxxxxxxxxxxx>]

On a protection exception, test that the Translation-Exception
Identification (TEID) values are correct given the circumstances of the
particular test.
The meaning of the TEID values is dependent on the installed
suppression-on-protection facility.

Signed-off-by: Janis Schoetterl-Glausch <scgl@xxxxxxxxxxxxx>
---
 s390x/skey.c | 78 ++++++++++++++++++++++++++++++++++++++++++++++++----
 1 file changed, 72 insertions(+), 6 deletions(-)

diff --git a/s390x/skey.c b/s390x/skey.c
index 445476a0..efce1fc3 100644
--- a/s390x/skey.c
+++ b/s390x/skey.c
@@ -8,6 +8,7 @@
  *  Janosch Frank <frankja@xxxxxxxxxxxxxxxxxx>
  */
 #include <libcflat.h>
+#include <asm/arch_def.h>
 #include <asm/asm-offsets.h>
 #include <asm/interrupt.h>
 #include <vmalloc.h>
@@ -158,6 +159,71 @@ static void test_test_protection(void)
 	report_prefix_pop();
 }
 
+enum access {
+	ACC_STORE = 1,
+	ACC_FETCH = 2,
+	ACC_UPDATE = 3,
+};
+
+enum protection {
+	PROT_STORE = 1,
+	PROT_FETCH_STORE = 3,
+};
+
+static void check_key_prot_exc(enum access access, enum protection prot)
+{
+	union teid teid;
+	int access_code;
+
+	check_pgm_int_code(PGM_INT_CODE_PROTECTION);
+	report_prefix_push("TEID");
+	teid.val = lowcore.trans_exc_id;
+	switch (get_supp_on_prot_facility()) {
+	case SOP_NONE:
+	case SOP_BASIC:
+		/* let's ignore ancient/irrelevant machines */
+		break;
+	case SOP_ENHANCED_1:
+		report(!teid.sop_teid_predictable, "valid protection code");
+		/* no access code in case of key protection */
+		break;
+	case SOP_ENHANCED_2:
+		switch (teid_esop2_prot_code(teid)) {
+		case PROT_KEY:
+			/* ESOP-2: no need to check facility */
+			access_code = teid.acc_exc_fetch_store;
+
+			switch (access_code) {
+			case 0:
+				report_pass("valid access code");
+				break;
+			case 1:
+			case 2:
+				report((access & access_code) && (prot & access_code),
+				       "valid access code");
+				break;
+			case 3:
+				/*
+				 * This is incorrect in that reserved values
+				 * should be ignored, but kvm should not return
+				 * a reserved value and having a test for that
+				 * is more valuable.
+				 */
+				report_fail("valid access code");
+				break;
+			}
+			/* fallthrough */
+		case PROT_KEY_OR_LAP:
+			report_pass("valid protection code");
+			break;
+		default:
+			report_fail("valid protection code");
+		}
+		break;
+	}
+	report_prefix_pop();
+}
+
 /*
  * Perform STORE CPU ADDRESS (STAP) instruction while temporarily executing
  * with access key 1.
@@ -199,7 +265,7 @@ static void test_store_cpu_address(void)
 	expect_pgm_int();
 	*out = 0xbeef;
 	store_cpu_address_key_1(out);
-	check_pgm_int_code(PGM_INT_CODE_PROTECTION);
+	check_key_prot_exc(ACC_STORE, PROT_STORE);
 	report(*out == 0xbeef, "no store occurred");
 	report_prefix_pop();
 
@@ -210,7 +276,7 @@ static void test_store_cpu_address(void)
 	expect_pgm_int();
 	*out = 0xbeef;
 	store_cpu_address_key_1(out);
-	check_pgm_int_code(PGM_INT_CODE_PROTECTION);
+	check_key_prot_exc(ACC_STORE, PROT_STORE);
 	report(*out == 0xbeef, "no store occurred");
 	report_prefix_pop();
 
@@ -228,7 +294,7 @@ static void test_store_cpu_address(void)
 	expect_pgm_int();
 	*out = 0xbeef;
 	store_cpu_address_key_1(out);
-	check_pgm_int_code(PGM_INT_CODE_PROTECTION);
+	check_key_prot_exc(ACC_STORE, PROT_STORE);
 	report(*out == 0xbeef, "no store occurred");
 	report_prefix_pop();
 
@@ -314,7 +380,7 @@ static void test_set_prefix(void)
 	set_storage_key(pagebuf, 0x28, 0);
 	expect_pgm_int();
 	set_prefix_key_1(prefix_ptr);
-	check_pgm_int_code(PGM_INT_CODE_PROTECTION);
+	check_key_prot_exc(ACC_FETCH, PROT_FETCH_STORE);
 	report(get_prefix() == old_prefix, "did not set prefix");
 	report_prefix_pop();
 
@@ -327,7 +393,7 @@ static void test_set_prefix(void)
 	install_page(root, virt_to_pte_phys(root, pagebuf), 0);
 	set_prefix_key_1((uint32_t *)0);
 	install_page(root, 0, 0);
-	check_pgm_int_code(PGM_INT_CODE_PROTECTION);
+	check_key_prot_exc(ACC_FETCH, PROT_FETCH_STORE);
 	report(get_prefix() == old_prefix, "did not set prefix");
 	report_prefix_pop();
 
@@ -351,7 +417,7 @@ static void test_set_prefix(void)
 	install_page(root, virt_to_pte_phys(root, pagebuf), 0);
 	set_prefix_key_1(OPAQUE_PTR(2048));
 	install_page(root, 0, 0);
-	check_pgm_int_code(PGM_INT_CODE_PROTECTION);
+	check_key_prot_exc(ACC_FETCH, PROT_FETCH_STORE);
 	report(get_prefix() == old_prefix, "did not set prefix");
 	report_prefix_pop();
 
-- 
2.36.1