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 | 417 ++++++++++++++++++++++++++++++++++++++++++++++++++++ s390x/unittests.cfg | 3 + 3 files changed, 421 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..3267a92 --- /dev/null +++ b/s390x/sclp.c @@ -0,0 +1,417 @@ +/* + * 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_NONE 1 +#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(); + 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. + * Returns 1 in case of success or 0 in case of failure + */ +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; + + /* Copy the template to the test address if needed */ + if (len) + memcpy(addr, sccb_template, len); + 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 = clear_pgm_int(); + /* Check if the program exception was one of the expected ones */ + 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; + } + /* Check if the response code is the one expected */ + 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 a simple SCCB template. + * Returns 1 in case of success or 0 in case of failure + */ +static int test_one_simple(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; + return test_one_sccb(cmd, addr, buf_len, exp_pgm, exp_rc); +} + +/** + * Test SCCB lengths < 8. + */ +static void test_sccb_too_short(void) +{ + int len; + + for (len = 0; len < 8; len++) + if (!test_one_simple(valid_code, pagebuf, len, 8, PGM_BIT_SPEC, 0)) + break; + + report("SCCB too short", len == 8); +} + +/** + * Test SCCBs that are not 64-bit aligned. + */ +static void test_sccb_unaligned(void) +{ + int offset; + + for (offset = 1; offset < 8; offset++) + if (!test_one_simple(valid_code, offset + pagebuf, 8, 8, PGM_BIT_SPEC, 0)) + break; + report("SCCB unaligned", offset == 8); +} + +/** + * Test SCCBs whose address is in the lowcore or prefix area. + */ +static void test_sccb_prefix(void) +{ + uint32_t prefix, new_prefix; + int offset; + + /* can't actually trash the lowcore, unsurprisingly things break if we do */ + for (offset = 0; offset < 8192; offset += 8) + if (!test_one_sccb(valid_code, MKPTR(offset), 0, PGM_BIT_SPEC, 0)) + break; + report("SCCB low pages", offset == 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 (offset = 0; offset < 8192; offset += 8) + if (!test_one_simple(valid_code, MKPTR(new_prefix + offset), 8, 8, PGM_BIT_SPEC, 0)) + break; + report("SCCB prefix pages", offset == 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 i, pgm, len = 0; + + h->length = 8; + + for (i = 0; i < 33; i++) + a[len++] = 1UL << (i + 31); + for (i = 0; i < 33; i++) + a[len++] = 3UL << (i + 31); + for (i = 0; i < 33; i++) + a[len++] = 0xffffffff80000000UL << i; + a[len++] = 0x80000000; + for (i = 1; i < 33; i++, len++) + a[len] = a[len - 1] | (1UL << (i + 31)); + for (i = 0; i < len; i++) + a[len + i] = a[i] + (intptr_t)h; + len += i; + a[len++] = 0xdeadbeef00000000; + a[len++] = 0xdeaddeadbeef0000; + + maxram = get_ram_size(); + for (i = 0; i < len; i++) { + pgm = PGM_BIT_SPEC | (a[i] >= maxram ? PGM_BIT_ADDR : 0); + if (!test_one_sccb(valid_code, (void *)a[i], 0, pgm, 0)) + break; + } + report("SCCB high addresses", i == len); +} + +/** + * Test invalid commands, both invalid command detail codes and valid + * ones with invalid command class code. + */ +static void test_inval(void) +{ + const uint16_t res = SCLP_RC_INVALID_SCLP_COMMAND; + uint32_t cmd; + int i; + + report_prefix_push("Invalid command"); + for (i = 0; i < 65536; i++) { + cmd = (0xdead0000) | i; + if (!test_one_simple(cmd, pagebuf, PAGE_SIZE, PAGE_SIZE, PGM_NONE, res)) + break; + } + report("Command detail code", i == 65536); + + for (i = 0; i < 256; i++) { + cmd = (valid_code & ~0xff) | i; + if (cmd == valid_code) + continue; + if (!test_one_simple(cmd, pagebuf, PAGE_SIZE, PAGE_SIZE, PGM_NONE, res)) + break; + } + report("Command class code", i == 256); + report_prefix_pop(); +} + + +/** + * Test short SCCBs (but larger than 8). + */ +static void test_short(void) +{ + const uint16_t res = SCLP_RC_INSUFFICIENT_SCCB_LENGTH; + int i; + + for (i = 8; i < 144; i++) + if (!test_one_simple(valid_code, pagebuf, i, i, PGM_NONE, res)) + break; + report("Insufficient SCCB length (Read SCP info)", i == 144); + + for (i = 8; i < 40; i++) + if (!test_one_simple(SCLP_READ_CPU_INFO, pagebuf, i, i, PGM_NONE, res)) + break; + report("Insufficient SCCB length (Read CPU info)", i == 40); +} + +/** + * Test SCCB page boundary violations. + */ +static void test_boundary(void) +{ + const uint32_t cmd = SCLP_CMD_WRITE_EVENT_DATA; + const uint16_t res = SCLP_RC_SCCB_BOUNDARY_VIOLATION; + WriteEventData *sccb = (WriteEventData *)sccb_template; + int len, i; + + memset(sccb_template, 0, sizeof(sccb_template)); + sccb->h.function_code = SCLP_FC_NORMAL_WRITE; + for (len = 32; len <= 4096; len++) { + i = len & 7 ? len & ~7 : len - 8; + for (i = 4096 - i; i < 4096; i += 8) { + sccb->h.length = len; + if (!test_one_sccb(cmd, i + pagebuf, len, PGM_NONE, res)) + goto out; + } + } +out: + report("SCCB page boundary violation", len > 4096 && i == 4096); +} + +/** + * Test excessively long SCCBs. + */ +static void test_toolong(void) +{ + const uint32_t cmd = SCLP_CMD_WRITE_EVENT_DATA; + const uint16_t res = SCLP_RC_SCCB_BOUNDARY_VIOLATION; + WriteEventData *sccb = (WriteEventData *)sccb_template; + int i; + + memset(sccb_template, 0, sizeof(sccb_template)); + sccb->h.function_code = SCLP_FC_NORMAL_WRITE; + for (i = 4097; i < 8192; i++) { + sccb->h.length = i; + if (!test_one_sccb(cmd, pagebuf, PAGE_SIZE, PGM_NONE, res)) + break; + } + report("SCCB bigger than 4k", i == 8192); +} + +/** + * Test privileged operation. + */ +static void test_priv(void) +{ + SCCBHeader *h = (SCCBHeader *)pagebuf; + + report_prefix_push("Privileged operation"); + h->length = 8; + expect_pgm_int(); + enter_pstate(); + servc(valid_code, __pa(h)); + 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 i, maxram = get_ram_size(); + + if (maxram >= 0x80000000) { + report_skip("Invalid SCCB address"); + return; + } + for (i = maxram; i < MIN(maxram + 65536, 0x80000000); i += 8) + if (!test_one_sccb(valid_code, (void *)i, 0, PGM_BIT_ADDR, 0)) + goto out; + for (; i < MIN((maxram + 0x7fffff) & ~0xfffff, 0x80000000); i += 4096) + if (!test_one_sccb(valid_code, (void *)i, 0, PGM_BIT_ADDR, 0)) + goto out; + for (; i < 0x80000000; i += 1048576) + if (!test_one_sccb(valid_code, (void *)i, 0, PGM_BIT_ADDR, 0)) + goto out; +out: + report("Invalid SCCB address", i == 0x80000000); +} + +/** + * Test some bits in the instruction format that are specified to be ignored. + */ +static void test_instbits(void) +{ + SCCBHeader *h = (SCCBHeader *)pagebuf; + int cc; + + expect_pgm_int(); + sclp_mark_busy(); + h->length = 8; + sclp_setup_int_test(); + + 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"); + if (lc->pgm_int_code) { + sclp_handle_ext(); + cc = 1; + } else if (!cc) + 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) +{ + const 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(*h)); + 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 -- 2.7.4