tests/qtest/boot-sector.c

   1 /*
   2  * QEMU boot sector testing helpers.
   3  *
   4  * Copyright (c) 2016 Red Hat Inc.
   5  *
   6  * Authors:
   7  *  Michael S. Tsirkin <mst@redhat.com>
   8  *  Victor Kaplansky <victork@redhat.com>
   9  *
  10  * This work is licensed under the terms of the GNU GPL, version 2 or later.
  11  * See the COPYING file in the top-level directory.
  12  */
  13 #include "qemu/osdep.h"
  14 #include "boot-sector.h"
  15 #include "libqtest.h"
  16
  17 #define LOW(x) ((x) & 0xff)
  18 #define HIGH(x) ((x) >> 8)
  19
  20 #define SIGNATURE 0xdead
  21 #define SIGNATURE_OFFSET 0x10
  22 #define BOOT_SECTOR_ADDRESS 0x7c00
  23 #define SIGNATURE_ADDR (BOOT_SECTOR_ADDRESS + SIGNATURE_OFFSET)
  24
  25 /* x86 boot sector code: write SIGNATURE into memory,
  26  * then halt.
  27  */
  28 static uint8_t x86_boot_sector[512] = {
  29     /* The first sector will be placed at RAM address 00007C00, and
  30      * the BIOS transfers control to 00007C00
  31      */
  32
  33     /* Data Segment register should be initialized, since pxe
  34      * boot loader can leave it dirty.
  35      */
  36
  37     /* 7c00: move $0000,%ax */
  38     [0x00] = 0xb8,
  39     [0x01] = 0x00,
  40     [0x02] = 0x00,
  41     /* 7c03: move %ax,%ds */
  42     [0x03] = 0x8e,
  43     [0x04] = 0xd8,
  44
  45     /* 7c05: mov $0xdead,%ax */
  46     [0x05] = 0xb8,
  47     [0x06] = LOW(SIGNATURE),
  48     [0x07] = HIGH(SIGNATURE),
  49     /* 7c08:  mov %ax,0x7c10 */
  50     [0x08] = 0xa3,
  51     [0x09] = LOW(SIGNATURE_ADDR),
  52     [0x0a] = HIGH(SIGNATURE_ADDR),
  53
  54     /* 7c0b cli */
  55     [0x0b] = 0xfa,
  56     /* 7c0c: hlt */
  57     [0x0c] = 0xf4,
  58     /* 7c0e: jmp 0x7c07=0x7c0f-3 */
  59     [0x0d] = 0xeb,
  60     [0x0e] = LOW(-3),
  61     /* We mov 0xdead here: set value to make debugging easier */
  62     [SIGNATURE_OFFSET] = LOW(0xface),
  63     [SIGNATURE_OFFSET + 1] = HIGH(0xface),
  64     /* End of boot sector marker */
  65     [0x1FE] = 0x55,
  66     [0x1FF] = 0xAA,
  67 };
  68
  69 /* For s390x, use a mini "kernel" with the appropriate signature */
  70 static const uint8_t s390x_psw_and_magic[] = {
  71     0x00, 0x08, 0x00, 0x00, 0x80, 0x01, 0x00, 0x00,  /* Program status word  */
  72     0x02, 0x00, 0x00, 0x18, 0x60, 0x00, 0x00, 0x50,  /* Magic:               */
  73     0x02, 0x00, 0x00, 0x68, 0x60, 0x00, 0x00, 0x50,  /* see linux_s390_magic */
  74     0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40   /* in the s390-ccw bios */
  75 };
  76 static const uint8_t s390x_code[] = {
  77     0xa7, 0xf4, 0x00, 0x08,                                /* j 0x10010 */
  78     0x00, 0x00, 0x00, 0x00,
  79     'S', '3', '9', '0',
  80     'E', 'P', 0x00, 0x01,
  81     0xa7, 0x39, HIGH(SIGNATURE_ADDR), LOW(SIGNATURE_ADDR), /* lghi r3,0x7c10 */
  82     0xa7, 0x48, LOW(SIGNATURE), HIGH(SIGNATURE),           /* lhi r4,0xadde */
  83     0x40, 0x40, 0x30, 0x00,                                /* sth r4,0(r3) */
  84     0xa7, 0xf4, 0xff, 0xfa                                 /* j 0x10010 */
  85 };
  86
  87 /* Create boot disk file.  */
  88 int boot_sector_init(char *fname)
  89 {
  90     int fd, ret;
  91     size_t len;
  92     char *boot_code;
  93     const char *arch = qtest_get_arch();
  94
  95     fd = mkstemp(fname);
  96     if (fd < 0) {
  97         fprintf(stderr, "Couldn't open \"%s\": %s", fname, strerror(errno));
  98         return 1;
  99     }
 100
 101     if (g_str_equal(arch, "i386") || g_str_equal(arch, "x86_64")) {
 102         /* Q35 requires a minimum 0x7e000 bytes disk (bug or feature?) */
 103         len = MAX(0x7e000, sizeof(x86_boot_sector));
 104         boot_code = g_malloc0(len);
 105         memcpy(boot_code, x86_boot_sector, sizeof(x86_boot_sector));
 106     } else if (g_str_equal(arch, "ppc64")) {
 107         /* For Open Firmware based system, use a Forth script */
 108         boot_code = g_strdup_printf("\\ Bootscript\n%x %x c! %x %x c!\n",
 109                                     LOW(SIGNATURE), SIGNATURE_ADDR,
 110                                     HIGH(SIGNATURE), SIGNATURE_ADDR + 1);
 111         len = strlen(boot_code);
 112     } else if (g_str_equal(arch, "s390x")) {
 113         len = 0x10000 + sizeof(s390x_code);
 114         boot_code = g_malloc0(len);
 115         memcpy(boot_code, s390x_psw_and_magic, sizeof(s390x_psw_and_magic));
 116         memcpy(&boot_code[0x10000], s390x_code, sizeof(s390x_code));
 117     } else {
 118         g_assert_not_reached();
 119     }
 120
 121     ret = write(fd, boot_code, len);
 122     close(fd);
 123
 124     g_free(boot_code);
 125
 126     if (ret != len) {
 127         fprintf(stderr, "Could not write \"%s\"", fname);
 128         return 1;
 129     }
 130
 131     return 0;
 132 }
 133
 134 /* Loop until signature in memory is OK.  */
 135 void boot_sector_test(QTestState *qts)
 136 {
 137     uint8_t signature_low;
 138     uint8_t signature_high;
 139     uint16_t signature;
 140     QDict *qrsp, *qret;
 141     int i;
 142
 143     /* Wait at most 600 seconds (test is slow with TCI and --enable-debug) */
 144 #define TEST_DELAY (1 * G_USEC_PER_SEC / 10)
 145 #define TEST_CYCLES MAX((600 * G_USEC_PER_SEC / TEST_DELAY), 1)
 146
 147     /* Poll until code has run and modified memory.  Once it has we know BIOS
 148      * initialization is done.  TODO: check that IP reached the halt
 149      * instruction.
 150      */
 151     for (i = 0; i < TEST_CYCLES; ++i) {
 152         signature_low = qtest_readb(qts, SIGNATURE_ADDR);
 153         signature_high = qtest_readb(qts, SIGNATURE_ADDR + 1);
 154         signature = (signature_high << 8) | signature_low;
 155         if (signature == SIGNATURE) {
 156             break;
 157         }
 158
 159         /* check that guest is still in "running" state and did not panic */
 160         qrsp = qtest_qmp(qts, "{ 'execute': 'query-status' }");
 161         qret = qdict_get_qdict(qrsp, "return");
 162         g_assert_nonnull(qret);
 163         g_assert_cmpstr(qdict_get_try_str(qret, "status"), ==, "running");
 164         qobject_unref(qrsp);
 165
 166         g_usleep(TEST_DELAY);
 167     }
 168
 169     g_assert_cmphex(signature, ==, SIGNATURE);
 170 }
 171
 172 /* unlink boot disk file.  */
 173 void boot_sector_cleanup(const char *fname)
 174 {
 175     unlink(fname);
 176 }