[kvm-unit-tests PATCH v5 4/6] s390x: css: implementing Set CHannel Monitor

[Pierre Morel <pmorel@linux.ibm.com>]

We implement the call of the Set CHannel Monitor instruction,
starting the monitoring of the all Channel Sub System, and
initializing channel subsystem monitoring.

Initial tests report the presence of the extended measurement block
feature, and verify the error reporting of the hypervisor for SCHM.

Signed-off-by: Pierre Morel <pmorel@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Acked-by: Janosch Frank <frankja@linux.ibm.com>
---
 lib/s390x/css.h     | 16 ++++++++++++++--
 lib/s390x/css_lib.c |  4 ++--
 s390x/css.c         | 35 +++++++++++++++++++++++++++++++++++
 3 files changed, 51 insertions(+), 4 deletions(-)

diff --git a/lib/s390x/css.h b/lib/s390x/css.h
index 3c50fa8..7158423 100644
--- a/lib/s390x/css.h
+++ b/lib/s390x/css.h
@@ -309,6 +309,7 @@ struct chsc_scsc {
 	uint8_t reserved[9];
 	struct chsc_header res;
 	uint32_t res_fmt;
+#define CSSC_EXTENDED_MEASUREMENT_BLOCK 48
 	uint64_t general_char[255];
 	uint64_t chsc_char[254];
 };
@@ -356,8 +357,19 @@ static inline int _chsc(void *p)
 bool chsc(void *p, uint16_t code, uint16_t len);
 
 #include <bitops.h>
-#define css_general_feature(bit) test_bit_inv(bit, chsc_scsc->general_char)
-#define css_chsc_feature(bit) test_bit_inv(bit, chsc_scsc->chsc_char)
+#define css_test_general_feature(bit) test_bit_inv(bit, chsc_scsc->general_char)
+#define css_test_chsc_feature(bit) test_bit_inv(bit, chsc_scsc->chsc_char)
+
+#define SCHM_DCTM	1 /* activate Device Connection TiMe */
+#define SCHM_MBU	2 /* activate Measurement Block Update */
+
+static inline void schm(void *mbo, unsigned int flags)
+{
+	register void *__gpr2 asm("2") = mbo;
+	register long __gpr1 asm("1") = flags;
+
+	asm("schm" : : "d" (__gpr2), "d" (__gpr1));
+}
 
 bool css_enable_mb(int sid, uint64_t mb, uint16_t mbi, uint16_t flg, bool fmt1);
 bool css_disable_mb(int schid);
diff --git a/lib/s390x/css_lib.c b/lib/s390x/css_lib.c
index 77b39c7..95d9a78 100644
--- a/lib/s390x/css_lib.c
+++ b/lib/s390x/css_lib.c
@@ -94,7 +94,7 @@ bool get_chsc_scsc(void)
 		return false;
 
 	for (i = 0, p = buffer; i < CSS_GENERAL_FEAT_BITLEN; i++) {
-		if (css_general_feature(i)) {
+		if (css_test_general_feature(i)) {
 			n = snprintf(p, sizeof(buffer), "%d,", i);
 			p += n;
 		}
@@ -102,7 +102,7 @@ bool get_chsc_scsc(void)
 	report_info("General features: %s", buffer);
 
 	for (i = 0, p = buffer; i < CSS_CHSC_FEAT_BITLEN; i++) {
-		if (css_chsc_feature(i)) {
+		if (css_test_chsc_feature(i)) {
 			n = snprintf(p, sizeof(buffer), "%d,", i);
 			p += n;
 		}
diff --git a/s390x/css.c b/s390x/css.c
index 069c2be..a763814 100644
--- a/s390x/css.c
+++ b/s390x/css.c
@@ -149,6 +149,40 @@ static void css_init(void)
 	report(get_chsc_scsc(), "Store Channel Characteristics");
 }
 
+static void test_schm(void)
+{
+	if (css_test_general_feature(CSSC_EXTENDED_MEASUREMENT_BLOCK))
+		report_info("Extended measurement block available");
+
+	/* bits 59-63 of MB address must be 0  if MBU is defined */
+	report_prefix_push("Unaligned operand");
+	expect_pgm_int();
+	schm((void *)0x01, SCHM_MBU);
+	check_pgm_int_code(PGM_INT_CODE_OPERAND);
+	report_prefix_pop();
+
+	/* bits 36-61 of register 1 (flags) must be 0 */
+	report_prefix_push("Bad flags");
+	expect_pgm_int();
+	schm(NULL, 0xfffffffc);
+	check_pgm_int_code(PGM_INT_CODE_OPERAND);
+	report_prefix_pop();
+
+	/* SCHM is a privilege operation */
+	report_prefix_push("Privilege");
+	enter_pstate();
+	expect_pgm_int();
+	schm(NULL, SCHM_MBU);
+	check_pgm_int_code(PGM_INT_CODE_PRIVILEGED_OPERATION);
+	report_prefix_pop();
+
+	/* Normal operation */
+	report_prefix_push("Normal operation");
+	schm(NULL, SCHM_MBU);
+	report(1, "SCHM call without address");
+	report_prefix_pop();
+}
+
 static struct {
 	const char *name;
 	void (*func)(void);
@@ -158,6 +192,7 @@ static struct {
 	{ "enumerate (stsch)", test_enumerate },
 	{ "enable (msch)", test_enable },
 	{ "sense (ssch/tsch)", test_sense },
+	{ "measurement block (schm)", test_schm },
 	{ NULL, NULL }
 };
 
-- 
2.17.1