SCLP unit test. Testing the following:
* Correctly ignoring instruction bits that should be ignored
* Privileged instruction check
* Check for addressing exceptions
* Specification exceptions:
- SCCB size less than 8
- SCCB unaligned
- SCCB overlaps prefix or lowcore
- SCCB address higher than 2GB
* Return codes for
- Invalid command
- SCCB too short (but at least 8)
- SCCB page boundary violation
Signed-off-by: Claudio Imbrenda <imbrenda@xxxxxxxxxxxxx>
---
s390x/Makefile | 1 +
s390x/sclp.c | 413 ++++++++++++++++++++++++++++++++++++++++++++++++++++
s390x/unittests.cfg | 3 +
3 files changed, 417 insertions(+)
create mode 100644 s390x/sclp.c
diff --git a/s390x/Makefile b/s390x/Makefile
index 3744372..ddb4b48 100644
--- a/s390x/Makefile
+++ b/s390x/Makefile
@@ -16,6 +16,7 @@ tests += $(TEST_DIR)/diag288.elf
tests += $(TEST_DIR)/stsi.elf
tests += $(TEST_DIR)/skrf.elf
tests += $(TEST_DIR)/smp.elf
+tests += $(TEST_DIR)/sclp.elf
tests_binary = $(patsubst %.elf,%.bin,$(tests))
all: directories test_cases test_cases_binary
diff --git a/s390x/sclp.c b/s390x/sclp.c
new file mode 100644
index 0000000..29ac265
--- /dev/null
+++ b/s390x/sclp.c
@@ -0,0 +1,413 @@
+/*
+ * Service Call tests
+ *
+ * Copyright (c) 2019 IBM Corp
+ *
+ * Authors:
+ * Claudio Imbrenda <imbrenda@xxxxxxxxxxxxx>
+ *
+ * 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 <asm/page.h>
+#include <asm/asm-offsets.h>
+#include <asm/interrupt.h>
+#include <sclp.h>
+
+#define PGM_BIT_SPEC (1ULL << PGM_INT_CODE_SPECIFICATION)
+#define PGM_BIT_ADDR (1ULL << PGM_INT_CODE_ADDRESSING)
+#define PGM_BIT_PRIV (1ULL << PGM_INT_CODE_PRIVILEGED_OPERATION)
+#define MKPTR(x) ((void *)(uint64_t)(x))
+
+static uint8_t pagebuf[PAGE_SIZE * 2] __attribute__((aligned(PAGE_SIZE * 2)));
+static uint8_t prefix_buf[PAGE_SIZE * 2] __attribute__((aligned(PAGE_SIZE * 2)));
+static uint8_t sccb_template[PAGE_SIZE];
+static uint32_t valid_code;
+static struct lowcore *lc;
+
+/**
+ * Enable SCLP interrupt.
+ */
+static void sclp_setup_int_test(void)
+{
+ uint64_t mask;
+
+ ctl_set_bit(0, 9);
+ mask = extract_psw_mask();
+ mask |= PSW_MASK_EXT;
+ load_psw_mask(mask);
+}
+
+/**
+ * Perform one service call, handling exceptions and interrupts.
+ */
+static int sclp_service_call_test(unsigned int command, void *sccb)
+{
+ int cc;
+
+ sclp_mark_busy();
+ sclp_setup_int_test();
+ lc->pgm_int_code = 0;
+ cc = servc(command, __pa(sccb));
+ if (lc->pgm_int_code) {
+ sclp_handle_ext();
+ return 0;
+ }
+ if (!cc)
+ sclp_wait_busy();
+ return cc;
+}
+
+/**
+ * Perform one test at the given address, optionally using the SCCB template,
+ * checking for the expected program interrupts and return codes.
+ */
+static int test_one_sccb(uint32_t cmd, uint8_t *addr, uint16_t len,
+ uint64_t exp_pgm, uint16_t exp_rc)
+{
+ SCCBHeader *h = (SCCBHeader *)addr;
+ int res, pgm;
+
+ if (len)
+ memcpy(addr, sccb_template, len);
+ if (!exp_pgm)
+ exp_pgm = 1;
+ expect_pgm_int();
+ res = sclp_service_call_test(cmd, h);
+ if (res) {
+ report_info("SCLP not ready (command %#x, address %p, cc %d)", cmd, addr, res);
+ return 0;
+ }
+ pgm = lc->pgm_int_code;
+ if (!((1ULL << pgm) & exp_pgm)) {
+ report_info("First failure at addr %p, size %d, cmd %#x, pgm code %d", addr, len, cmd, pgm);
+ return 0;
+ }
+ if (exp_rc && (exp_rc != h->response_code)) {
+ report_info("First failure at addr %p, size %d, cmd %#x, resp code %#x",
+ addr, len, cmd, h->response_code);
+ return 0;
+ }
+ return 1;
+}
+
+/**
+ * Wrapper for test_one_sccb to set up an SCCB template
+ */
+static int test_one_run(uint32_t cmd, uint8_t *addr, uint16_t sccb_len,
+ uint16_t buf_len, uint64_t exp_pgm, uint16_t exp_rc)
+{
+ if (buf_len)
+ memset(sccb_template, 0, sizeof(sccb_template));
+ ((SCCBHeader *)sccb_template)->length = sccb_len;
+ if (buf_len && buf_len < 8)
+ buf_len = 8;
+ return test_one_sccb(cmd, addr, buf_len, exp_pgm, exp_rc);
+}
+
+/**
+ * Test SCCB lengths < 8
+ */
+static void test_sccb_too_short(void)
+{
+ int cx;
+
+ for (cx = 0; cx < 8; cx++)
+ if (!test_one_run(valid_code, pagebuf, cx, 8, PGM_BIT_SPEC, 0))
+ break;
+
+ report("SCCB too short", cx == 8);
+}
+
+/**
+ * Test SCCBs that are not 64bits aligned
+ */
+static void test_sccb_unaligned(void)
+{
+ int cx;
+
+ for (cx = 1; cx < 8; cx++)
+ if (!test_one_run(valid_code, cx + pagebuf, 8, 8, PGM_BIT_SPEC, 0))
+ break;
+ report("SCCB unaligned", cx == 8);
+}
+
+/**
+ * Test SCCBs whose address is in the lowcore or prefix area
+ */
+static void test_sccb_prefix(void)
+{
+ uint32_t prefix, new_prefix;
+ int cx;
+
+ // can't actually trash the lowcore, unsurprisingly things break if we do
+ for (cx = 0; cx < 8192; cx += 8)
+ if (!test_one_sccb(valid_code, MKPTR(cx), 0, PGM_BIT_SPEC, 0))
+ break;
+ report("SCCB low pages", cx == 8192);
+
+ memcpy(prefix_buf, 0, 8192);
+ new_prefix = (uint32_t)(intptr_t)prefix_buf;
+ asm volatile("stpx %0" : "=Q" (prefix));
+ asm volatile("spx %0" : : "Q" (new_prefix) : "memory");
+
+ for (cx = 0; cx < 8192; cx += 8)
+ if (!test_one_run(valid_code, MKPTR(new_prefix + cx), 8, 8, PGM_BIT_SPEC, 0))
+ break;
+ report("SCCB prefix pages", cx == 8192);
+
+ memcpy(prefix_buf, 0, 8192);
+ asm volatile("spx %0" : : "Q" (prefix) : "memory");
+}
+
+/**
+ * Test SCCBs that are above 2GB. If outside of memory, an addressing
+ * exception is also allowed.
+ */
+static void test_sccb_high(void)
+{
+ SCCBHeader *h = (SCCBHeader *)pagebuf;
+ uintptr_t a[33 * 4 * 2 + 2];
+ uint64_t maxram;
+ int cx, i, pgm;
+
+ h->length = 8;
+
+ i = 0;
+ for (cx = 0; cx < 33; cx++)
+ a[i++] = 1UL << (cx + 31);
+ for (cx = 0; cx < 33; cx++)
+ a[i++] = 3UL << (cx + 31);
+ for (cx = 0; cx < 33; cx++)
+ a[i++] = 0xffffffff80000000UL << cx;
+ a[i++] = 0x80000000;
+ for (cx = 1; cx < 33; cx++, i++)
+ a[i] = a[i - 1] | (1UL << (cx + 31));
+ for (cx = 0; cx < i; cx++)
+ a[i + cx] = a[cx] + (intptr_t)pagebuf;
+ i += cx;
+ a[i++] = 0xdeadbeef00000000;
+ a[i++] = 0xdeaddeadbeef0000;
+
+ maxram = get_ram_size();
+ for (cx = 0; cx < i; cx++) {
+ pgm = PGM_BIT_SPEC | (a[cx] >= maxram ? PGM_BIT_ADDR : 0);
+ if (!test_one_sccb(valid_code, (void *)a[cx], 0, pgm, 0))
+ break;
+ }
+ report("SCCB high addresses", cx == i);
+}
+
+/**
+ * Test invalid commands, both invalid command detail codes and valid
+ * ones with invalid command class code.
+ */
+static void test_inval(void)
+{
+ uint32_t cmd;
+ int cx;
+
+ report_prefix_push("Invalid command");
+ for (cx = 0; cx < 65536; cx++) {
+ cmd = (0xdead0000) | cx;
+ if (!test_one_run(cmd, pagebuf, PAGE_SIZE, PAGE_SIZE, 0, SCLP_RC_INVALID_SCLP_COMMAND))
+ break;
+ }
+ report("Command detail code", cx == 65536);
+
+ for (cx = 0; cx < 256; cx++) {
+ cmd = (valid_code & ~0xff) | cx;
+ if (cmd == valid_code)
+ continue;
+ if (!test_one_run(cmd, pagebuf, PAGE_SIZE, PAGE_SIZE, 0, SCLP_RC_INVALID_SCLP_COMMAND))
+ break;
+ }
+ report("Command class code", cx == 256);
+ report_prefix_pop();
+}
+
+
+/**
+ * Test short SCCBs (but larger than 8).
+ */
+static void test_short(void)
+{
+ uint16_t res = SCLP_RC_INSUFFICIENT_SCCB_LENGTH;
+ int cx;
+
+ for (cx = 8; cx < 144; cx++)
+ if (!test_one_run(valid_code, pagebuf, cx, cx, 0, res))
+ break;
+ report("Insufficient SCCB length (Read SCP info)", cx == 144);
+
+ for (cx = 8; cx < 40; cx++)
+ if (!test_one_run(SCLP_READ_CPU_INFO, pagebuf, cx, cx, 0, res))
+ break;
+ report("Insufficient SCCB length (Read CPU info)", cx == 40);
+}
+
+/**
+ * Test SCCB page boundary violations.
+ */
+static void test_boundary(void)
+{
+ uint32_t cmd = SCLP_CMD_WRITE_EVENT_DATA;
+ uint16_t res = SCLP_RC_SCCB_BOUNDARY_VIOLATION;
+ WriteEventData *sccb = (WriteEventData *)sccb_template;
+ int len, cx;
+
+ memset(sccb_template, 0, sizeof(sccb_template));
+ sccb->h.function_code = SCLP_FC_NORMAL_WRITE;
+ for (len = 32; len <= 4096; len++) {
+ cx = len & 7 ? len & ~7 : len - 8;
+ for (cx = 4096 - cx; cx < 4096; cx += 8) {
+ sccb->h.length = len;
+ if (!test_one_sccb(cmd, cx + pagebuf, len, 0, res))
+ goto out;
+ }
+ }
+out:
+ report("SCCB page boundary violation", len > 4096 && cx == 4096);
+}
+
+static void test_toolong(void)
+{
+ uint32_t cmd = SCLP_CMD_WRITE_EVENT_DATA;
+ uint16_t res = SCLP_RC_SCCB_BOUNDARY_VIOLATION;
+ WriteEventData *sccb = (WriteEventData *)sccb_template;
+ int cx;
+
+ memset(sccb_template, 0, sizeof(sccb_template));
+ sccb->h.function_code = SCLP_FC_NORMAL_WRITE;
+ for (cx = 4097; cx < 8192; cx++) {
+ sccb->h.length = cx;
+ if (!test_one_sccb(cmd, pagebuf, PAGE_SIZE, 0, res))
+ break;
+ }
+ report("SCCB bigger than 4k", cx == 8192);
+}
+
+/**
+ * Test privileged operation.
+ */
+static void test_priv(void)
+{
+ report_prefix_push("Privileged operation");
+ pagebuf[0] = 0;
+ pagebuf[1] = 8;
+ expect_pgm_int();
+ enter_pstate();
+ servc(valid_code, __pa(pagebuf));
+ check_pgm_int_code(PGM_INT_CODE_PRIVILEGED_OPERATION);
+ report_prefix_pop();
+}
+
+/**
+ * Test addressing exceptions. We need to test SCCB addresses between the
+ * end of available memory and 2GB, because after 2GB a specification
+ * exception is also allowed.
+ * Only applicable if the VM has less than 2GB of memory
+ */
+static void test_addressing(void)
+{
+ unsigned long cx, maxram = get_ram_size();
+
+ if (maxram >= 0x80000000) {
+ report_skip("Invalid SCCB address");
+ return;
+ }
+ for (cx = maxram; cx < MIN(maxram + 65536, 0x80000000); cx += 8)
+ if (!test_one_sccb(valid_code, (void *)cx, 0, PGM_BIT_ADDR, 0))
+ goto out;
+ for (; cx < MIN((maxram + 0x7fffff) & ~0xfffff, 0x80000000); cx += 4096)
+ if (!test_one_sccb(valid_code, (void *)cx, 0, PGM_BIT_ADDR, 0))
+ goto out;
+ for (; cx < 0x80000000; cx += 1048576)
+ if (!test_one_sccb(valid_code, (void *)cx, 0, PGM_BIT_ADDR, 0))
+ goto out;
+out:
+ report("Invalid SCCB address", cx == 0x80000000);
+}
+
+/**
+ * Test some bits in the instruction format that are specified to be ignored.
+ */
+static void test_instbits(void)
+{
+ SCCBHeader *h = (SCCBHeader *)pagebuf;
+ unsigned long mask;
+ int cc;
+
+ sclp_mark_busy();
+ h->length = 8;
+
+ ctl_set_bit(0, 9);
+ mask = extract_psw_mask();
+ mask |= PSW_MASK_EXT;
+ load_psw_mask(mask);
+
+ asm volatile(
+ " .insn rre,0xb2204200,%1,%2\n" /* servc %1,%2 */
+ " ipm %0\n"
+ " srl %0,28"
+ : "=&d" (cc) : "d" (valid_code), "a" (__pa(pagebuf))
+ : "cc", "memory");
+ sclp_wait_busy();
+ report("Instruction format ignored bits", cc == 0);
+}
+
+/**
+ * Find a valid SCLP command code; not all codes are always allowed, and
+ * probing should be performed in the right order.
+ */
+static void find_valid_sclp_code(void)
+{
+ unsigned int commands[] = { SCLP_CMDW_READ_SCP_INFO_FORCED,
+ SCLP_CMDW_READ_SCP_INFO };
+ SCCBHeader *h = (SCCBHeader *)pagebuf;
+ int i, cc;
+
+ for (i = 0; i < ARRAY_SIZE(commands); i++) {
+ sclp_mark_busy();
+ memset(h, 0, sizeof(pagebuf));
+ h->length = 4096;
+
+ valid_code = commands[i];
+ cc = sclp_service_call(commands[i], h);
+ if (cc)
+ break;
+ if (h->response_code == SCLP_RC_NORMAL_READ_COMPLETION)
+ return;
+ if (h->response_code != SCLP_RC_INVALID_SCLP_COMMAND)
+ break;
+ }
+ valid_code = 0;
+ report_abort("READ_SCP_INFO failed");
+}
+
+int main(void)
+{
+ report_prefix_push("sclp");
+ find_valid_sclp_code();
+
+ /* Test some basic things */
+ test_instbits();
+ test_priv();
+ test_addressing();
+
+ /* Test the specification exceptions */
+ test_sccb_too_short();
+ test_sccb_unaligned();
+ test_sccb_prefix();
+ test_sccb_high();
+
+ /* Test the expected response codes */
+ test_inval();
+ test_short();
+ test_boundary();
+ test_toolong();
+
+ return report_summary();
+}
diff --git a/s390x/unittests.cfg b/s390x/unittests.cfg
index f1b07cd..75e3d37 100644
--- a/s390x/unittests.cfg
+++ b/s390x/unittests.cfg
@@ -75,3 +75,6 @@ file = stsi.elf
[smp]
file = smp.elf
extra_params =-smp 2
+
+[sclp]
+file = sclp.elf
