[kvm-unit-tests RFC 2/2] s390x: mvpg: Add SIE mvpg test

[Janosch Frank <frankja@linux.ibm.com>]

Let's also check the PEI values to make sure our VSIE implementation
is correct.

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
---
 s390x/Makefile                  |   3 +-
 s390x/mvpg-sie.c                | 139 ++++++++++++++++++++++++++++++++
 s390x/snippets/c/mvpg-snippet.c |  33 ++++++++
 s390x/unittests.cfg             |   3 +
 4 files changed, 177 insertions(+), 1 deletion(-)
 create mode 100644 s390x/mvpg-sie.c
 create mode 100644 s390x/snippets/c/mvpg-snippet.c

diff --git a/s390x/Makefile b/s390x/Makefile
index fe267011..6692cf73 100644
--- a/s390x/Makefile
+++ b/s390x/Makefile
@@ -22,6 +22,7 @@ tests += $(TEST_DIR)/uv-guest.elf
 tests += $(TEST_DIR)/sie.elf
 tests += $(TEST_DIR)/mvpg.elf
 tests += $(TEST_DIR)/uv-host.elf
+tests += $(TEST_DIR)/mvpg-sie.elf
 
 tests_binary = $(patsubst %.elf,%.bin,$(tests))
 ifneq ($(HOST_KEY_DOCUMENT),)
@@ -79,7 +80,7 @@ FLATLIBS = $(libcflat)
 SNIPPET_DIR = $(TEST_DIR)/snippets
 
 # C snippets that need to be linked
-snippets-c =
+snippets-c = $(SNIPPET_DIR)/c/mvpg-snippet.gbin
 
 # ASM snippets that are directly compiled and converted to a *.gbin
 snippets-a =
diff --git a/s390x/mvpg-sie.c b/s390x/mvpg-sie.c
new file mode 100644
index 00000000..a617704b
--- /dev/null
+++ b/s390x/mvpg-sie.c
@@ -0,0 +1,139 @@
+#include <libcflat.h>
+#include <asm/asm-offsets.h>
+#include <asm-generic/barrier.h>
+#include <asm/interrupt.h>
+#include <asm/pgtable.h>
+#include <mmu.h>
+#include <asm/page.h>
+#include <asm/facility.h>
+#include <asm/mem.h>
+#include <asm/sigp.h>
+#include <smp.h>
+#include <alloc_page.h>
+#include <bitops.h>
+#include <vm.h>
+#include <sclp.h>
+#include <sie.h>
+
+static u8 *guest;
+static u8 *guest_instr;
+static struct vm vm;
+
+static uint8_t *src;
+static uint8_t *dst;
+
+extern const char _binary_s390x_snippets_c_mvpg_snippet_gbin_start[];
+extern const char _binary_s390x_snippets_c_mvpg_snippet_gbin_end[];
+int binary_size;
+
+static void handle_validity(struct vm *vm)
+{
+	report(0, "VALIDITY: %x", vm->sblk->ipb >> 16);
+}
+
+static void sie(struct vm *vm)
+{
+	/* Reset icptcode so we don't trip below */
+	vm->sblk->icptcode = 0;
+
+	while (vm->sblk->icptcode == 0) {
+		sie64a(vm->sblk, &vm->save_area);
+		if (vm->sblk->icptcode == ICPT_VALIDITY)
+			handle_validity(vm);
+	}
+	vm->save_area.guest.grs[14] = vm->sblk->gg14;
+	vm->save_area.guest.grs[15] = vm->sblk->gg15;
+}
+
+static void test_mvpg_pei(void)
+{
+	uint64_t **pei_dst = (uint64_t **)((uintptr_t) vm.sblk + 0xc0);
+	uint64_t **pei_src = (uint64_t **)((uintptr_t) vm.sblk + 0xc8);
+
+	report_prefix_push("pei");
+	protect_page(guest + 0x6000, PAGE_ENTRY_I);
+	sie(&vm);
+	report(vm.sblk->icptcode == ICPT_PARTEXEC, "Partial execution");
+	report((uintptr_t)**pei_src == ((uintptr_t)vm.sblk->mso) + 0x6000 + PAGE_ENTRY_I, "PEI_SRC correct");
+	report((uintptr_t)**pei_dst == vm.sblk->mso + 0x5000, "PEI_DST correct");
+	/* Jump over the diag44 */
+	sie(&vm);
+
+	/* Clear PEI data for next check */
+	memset((uint64_t *)((uintptr_t) vm.sblk + 0xc0), 0, 16);
+	unprotect_page(guest + 0x6000, PAGE_ENTRY_I);
+	protect_page(guest + 0x5000, PAGE_ENTRY_I);
+	sie(&vm);
+	report(vm.sblk->icptcode == ICPT_PARTEXEC, "Partial execution");
+	report((uintptr_t)**pei_src == vm.sblk->mso + 0x6000, "PEI_SRC correct");
+	report((uintptr_t)**pei_dst == vm.sblk->mso + 0x5000 + PAGE_ENTRY_I, "PEI_DST correct");
+
+	report_prefix_pop();
+}
+
+static void test_mvpg(void)
+{
+	int binary_size = ((uintptr_t)_binary_s390x_snippets_c_mvpg_snippet_gbin_end -
+			   (uintptr_t)_binary_s390x_snippets_c_mvpg_snippet_gbin_start);
+
+	memcpy(guest, _binary_s390x_snippets_c_mvpg_snippet_gbin_start, binary_size);
+	memset(src, 0x42, PAGE_SIZE);
+	memset(dst, 0x43, PAGE_SIZE);
+	sie(&vm);
+	mb();
+	report(!memcmp(src, dst, PAGE_SIZE) && *dst == 0x42, "Page moved");
+}
+
+static void setup_guest(void)
+{
+	setup_vm();
+
+	/* Allocate 1MB as guest memory */
+	guest = alloc_pages(8);
+	/* The first two pages are the lowcore */
+	guest_instr = guest + PAGE_SIZE * 2;
+
+	vm.sblk = alloc_page();
+
+	vm.sblk->cpuflags = CPUSTAT_ZARCH | CPUSTAT_RUNNING;
+	vm.sblk->prefix = 0;
+	/*
+	 * Pageable guest with the same ASCE as the test programm, but
+	 * the guest memory 0x0 is offset to start at the allocated
+	 * guest pages and end after 1MB.
+	 *
+	 * It's not pretty but faster and easier than managing guest ASCEs.
+	 */
+	vm.sblk->mso = (u64)guest;
+	vm.sblk->msl = (u64)guest;
+	vm.sblk->ihcpu = 0xffff;
+
+	vm.sblk->crycbd = (uint64_t)alloc_page();
+
+	vm.sblk->gpsw.addr = PAGE_SIZE * 4;
+	vm.sblk->gpsw.mask = 0x0000000180000000ULL;
+	vm.sblk->ictl = ICTL_OPEREXC | ICTL_PINT;
+	/* Enable MVPG interpretation as we want to test KVM and not ourselves */
+	vm.sblk->eca = ECA_MVPGI;
+
+	src = guest + PAGE_SIZE * 6;
+	dst = guest + PAGE_SIZE * 5;
+}
+
+int main(void)
+{
+	report_prefix_push("mvpg-sie");
+	if (!sclp_facilities.has_sief2) {
+		report_skip("SIEF2 facility unavailable");
+		goto done;
+	}
+
+	setup_guest();
+	test_mvpg();
+	test_mvpg_pei();
+
+done:
+	report_prefix_pop();
+	return report_summary();
+
+}
diff --git a/s390x/snippets/c/mvpg-snippet.c b/s390x/snippets/c/mvpg-snippet.c
new file mode 100644
index 00000000..96b70c9c
--- /dev/null
+++ b/s390x/snippets/c/mvpg-snippet.c
@@ -0,0 +1,33 @@
+#include <libcflat.h>
+
+static inline void force_exit(void)
+{
+	asm volatile("	diag	0,0,0x44\n");
+}
+
+static inline int mvpg(unsigned long r0, void *dest, void *src)
+{
+	register unsigned long reg0 asm ("0") = r0;
+	int cc;
+
+	asm volatile("	mvpg    %1,%2\n"
+		     "	ipm     %0\n"
+		     "	srl     %0,28"
+		     : "=&d" (cc) : "a" (dest), "a" (src), "d" (reg0)
+		     : "memory", "cc");
+	return cc;
+}
+
+static void test_mvpg_real(void)
+{
+	mvpg(0, (void *)0x5000, (void *)0x6000);
+	force_exit();
+}
+
+__attribute__((section(".text"))) int main(void)
+{
+	test_mvpg_real();
+	test_mvpg_real();
+	test_mvpg_real();
+	return 0;
+}
diff --git a/s390x/unittests.cfg b/s390x/unittests.cfg
index 9f81a608..8634b1b1 100644
--- a/s390x/unittests.cfg
+++ b/s390x/unittests.cfg
@@ -103,3 +103,6 @@ file = sie.elf
 [mvpg]
 file = mvpg.elf
 timeout = 10
+
+[mvpg-sie]
+file = mvpg-sie.elf
-- 
2.30.2