[kvm-unit-tests PATCH v2 3/3] s390x: Ultravisor guest API test

Janosch Frank
2020-08-07T11:16:07Z

Test the error conditions of guest 2 Ultravisor calls, namely:
* Query Ultravisor information
* Set shared access
* Remove shared access

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
---
lib/s390x/asm/uv.h | 74 ++++++++++++++++++++
s390x/Makefile | 1 +
s390x/unittests.cfg | 3 +
s390x/uv-guest.c | 162 ++++++++++++++++++++++++++++++++++++++++++++
4 files changed, 240 insertions(+)
create mode 100644 lib/s390x/asm/uv.h
create mode 100644 s390x/uv-guest.c

diff --git a/lib/s390x/asm/uv.h b/lib/s390x/asm/uv.h
new file mode 100644
index 0000000..4c2fc48
--- /dev/null
+++ b/lib/s390x/asm/uv.h
@@ -0,0 +1,74 @@
+/*
+ * s390x Ultravisor related definitions
+ *
+ * Copyright (c) 2020 IBM Corp
+ *
+ * Authors:
+ * Janosch Frank <frankja@linux.ibm.com>
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2.
+ */
+#ifndef UV_H
+#define UV_H
+
+#define UVC_RC_EXECUTED 0x0001
+#define UVC_RC_INV_CMD 0x0002
+#define UVC_RC_INV_STATE 0x0003
+#define UVC_RC_INV_LEN 0x0005
+#define UVC_RC_NO_RESUME 0x0007
+
+#define UVC_CMD_QUI 0x0001
+#define UVC_CMD_SET_SHARED_ACCESS 0x1000
+#define UVC_CMD_REMOVE_SHARED_ACCESS 0x1001
+
+/* Bits in installed uv calls */
+enum uv_cmds_inst {
+ BIT_UVC_CMD_QUI = 0,
+ BIT_UVC_CMD_SET_SHARED_ACCESS = 8,
+ BIT_UVC_CMD_REMOVE_SHARED_ACCESS = 9,
+};
+
+struct uv_cb_header {
+ u16 len;
+ u16 cmd; /* Command Code */
+ u16 rc; /* Response Code */
+ u16 rrc; /* Return Reason Code */
+} __attribute__((packed)) __attribute__((aligned(8)));
+
+struct uv_cb_qui {
+ struct uv_cb_header header;
+ u64 reserved08;
+ u64 inst_calls_list[4];
+ u64 reserved30[15];
+} __attribute__((packed)) __attribute__((aligned(8)));
+
+struct uv_cb_share {
+ struct uv_cb_header header;
+ u64 reserved08[3];
+ u64 paddr;
+ u64 reserved28;
+} __attribute__((packed)) __attribute__((aligned(8)));
+
+static inline int uv_call(unsigned long r1, unsigned long r2)
+{
+ int cc;
+
+ /*
+ * The brc instruction will take care of the cc 2/3 case where
+ * we need to continue the execution because we were
+ * interrupted. The inline assembly will only return on
+ * success/error i.e. cc 0/1.
+ */
+ asm volatile(
+ "0: .insn rrf,0xB9A40000,%[r1],%[r2],0,0\n"
+ " brc 3,0b\n"
+ " ipm %[cc]\n"
+ " srl %[cc],28\n"
+ : [cc] "=d" (cc)
+ : [r1] "a" (r1), [r2] "a" (r2)
+ : "memory", "cc");
+ return cc;
+}
+
+#endif
diff --git a/s390x/Makefile b/s390x/Makefile
index 0f54bf4..c2213ad 100644
--- a/s390x/Makefile
+++ b/s390x/Makefile
@@ -18,6 +18,7 @@ tests += $(TEST_DIR)/skrf.elf
tests += $(TEST_DIR)/smp.elf
tests += $(TEST_DIR)/sclp.elf
tests += $(TEST_DIR)/css.elf
+tests += $(TEST_DIR)/uv-guest.elf
tests_binary = $(patsubst %.elf,%.bin,$(tests))

all: directories test_cases test_cases_binary
diff --git a/s390x/unittests.cfg b/s390x/unittests.cfg
index b35269b..6d50c63 100644
--- a/s390x/unittests.cfg
+++ b/s390x/unittests.cfg
@@ -92,3 +92,6 @@ extra_params = -device virtio-net-ccw
[skrf]
file = skrf.elf
smp = 2
+
+[uv-guest]
+file = uv-guest.elf
diff --git a/s390x/uv-guest.c b/s390x/uv-guest.c
new file mode 100644
index 0000000..1aaf7ca
--- /dev/null
+++ b/s390x/uv-guest.c
@@ -0,0 +1,162 @@
+/*
+ * Guest Ultravisor Call tests
+ *
+ * Copyright (c) 2020 IBM Corp
+ *
+ * Authors:
+ * Janosch Frank <frankja@linux.ibm.com>
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2.
+ */
+
+#include <libcflat.h>
+#include <alloc_page.h>
+#include <asm/page.h>
+#include <asm/asm-offsets.h>
+#include <asm/interrupt.h>
+#include <asm/facility.h>
+#include <asm/uv.h>
+
+static unsigned long page;
+
+static inline int share(unsigned long addr, u16 cmd)
+{
+ struct uv_cb_share uvcb = {
+ .header.cmd = cmd,
+ .header.len = sizeof(uvcb),
+ .paddr = addr
+ };
+
+ uv_call(0, (u64)&uvcb);
+ return uvcb.header.rc;
+}
+
+static inline int uv_set_shared(unsigned long addr)
+{
+ return share(addr, UVC_CMD_SET_SHARED_ACCESS);
+}
+
+static inline int uv_remove_shared(unsigned long addr)
+{
+ return share(addr, UVC_CMD_REMOVE_SHARED_ACCESS);
+}
+
+static void test_priv(void)
+{
+ struct uv_cb_header uvcb = {};
+
+ report_prefix_push("privileged");
+
+ report_prefix_push("query");
+ expect_pgm_int();
+ uvcb.cmd = UVC_CMD_QUI;
+ uvcb.len = sizeof(struct uv_cb_qui);
+ enter_pstate();
+ uv_call(0, (u64)&uvcb);
+ check_pgm_int_code(PGM_INT_CODE_PRIVILEGED_OPERATION);
+ report_prefix_pop();
+
+ report_prefix_push("share");
+ expect_pgm_int();
+ enter_pstate();
+ uv_set_shared((unsigned long)page);
+ check_pgm_int_code(PGM_INT_CODE_PRIVILEGED_OPERATION);
+ report_prefix_pop();
+
+ report_prefix_push("unshare");
+ expect_pgm_int();
+ enter_pstate();
+ uv_remove_shared((unsigned long)page);
+ check_pgm_int_code(PGM_INT_CODE_PRIVILEGED_OPERATION);
+ report_prefix_pop();
+
+ report_prefix_pop();
+}
+
+static void test_query(void)
+{
+ struct uv_cb_qui uvcb = {
+ .header.cmd = UVC_CMD_QUI,
+ .header.len = sizeof(uvcb) - 8,
+ };
+ int cc;
+
+ report_prefix_push("query");
+ cc = uv_call(0, (u64)&uvcb);
+ report(cc == 1 && uvcb.header.rc == UVC_RC_INV_LEN, "length");
+
+ uvcb.header.len = sizeof(uvcb);
+ cc = uv_call(0, (u64)&uvcb);
+ report(cc == 0 && uvcb.header.rc == UVC_RC_EXECUTED, "successful query");
+
+ /*
+ * These bits have been introduced with the very first
+ * Ultravisor version and are expected to always be available
+ * because they are basic building blocks.
+ */
+ report(uvcb.inst_calls_list[0] & (1UL << (63 - BIT_UVC_CMD_QUI)),
+ "query indicated");
+ report(uvcb.inst_calls_list[0] & (1UL << (63 - BIT_UVC_CMD_SET_SHARED_ACCESS)),
+ "share indicated");
+ report(uvcb.inst_calls_list[0] & (1UL << (63 - BIT_UVC_CMD_REMOVE_SHARED_ACCESS)),
+ "unshare indicated");
+ report_prefix_pop();
+}
+
+static void test_sharing(void)
+{
+ struct uv_cb_share uvcb = {
+ .header.cmd = UVC_CMD_SET_SHARED_ACCESS,
+ .header.len = sizeof(uvcb) - 8,
+ };
+ int cc;
+
+ report_prefix_push("share");
+ cc = uv_call(0, (u64)&uvcb);
+ report(cc == 1 && uvcb.header.rc == UVC_RC_INV_LEN, "length");
+ report(uv_set_shared(page) == UVC_RC_EXECUTED, "share");
+ report_prefix_pop();
+
+ report_prefix_push("unshare");
+ uvcb.header.cmd = UVC_CMD_REMOVE_SHARED_ACCESS;
+ cc = uv_call(0, (u64)&uvcb);
+ report(cc == 1 && uvcb.header.rc == UVC_RC_INV_LEN, "length");
+ report(uv_remove_shared(page) == UVC_RC_EXECUTED, "unshare");
+ report_prefix_pop();
+
+ report_prefix_pop();
+}
+
+static void test_invalid(void)
+{
+ struct uv_cb_header uvcb = {
+ .len = 16,
+ .cmd = 0x4242,
+ };
+ int cc;
+
+ cc = uv_call(0, (u64)&uvcb);
+ report(cc == 1 && uvcb.rc == UVC_RC_INV_CMD, "invalid command");
+}
+
+int main(void)
+{
+ bool has_uvc = test_facility(158);
+
+ report_prefix_push("uvc");
+ if (!has_uvc) {
+ report_skip("Ultravisor call facility is not available");
+ goto done;
+ }
+
+ page = (unsigned long)alloc_page();
+ test_priv();
+ test_invalid();
+ test_query();
+ test_sharing();
+ free_page((void *)page);
+done:
+ report_prefix_pop();
+ return report_summary();
+}
--
2.25.1