qemu

boot-sector.c (5501B)

---

 /*
  * QEMU boot sector testing helpers.
  *
  * Copyright (c) 2016 Red Hat Inc.
  *
  * Authors:
  *  Michael S. Tsirkin <mst@redhat.com>
  *  Victor Kaplansky <victork@redhat.com>
  *
  * This work is licensed under the terms of the GNU GPL, version 2 or later.
  * See the COPYING file in the top-level directory.
  */
 #include "qemu/osdep.h"
 #include "boot-sector.h"
 #include "libqtest.h"
 
 #define LOW(x) ((x) & 0xff)
 #define HIGH(x) ((x) >> 8)
 
 #define SIGNATURE 0xdead
 #define SIGNATURE_OFFSET 0x10
 #define BOOT_SECTOR_ADDRESS 0x7c00
 #define SIGNATURE_ADDR (BOOT_SECTOR_ADDRESS + SIGNATURE_OFFSET)
 
 /* x86 boot sector code: write SIGNATURE into memory,
  * then halt.
  */
 static uint8_t x86_boot_sector[512] = {
     /* The first sector will be placed at RAM address 00007C00, and
      * the BIOS transfers control to 00007C00
      */
 
     /* Data Segment register should be initialized, since pxe
      * boot loader can leave it dirty.
      */
 
     /* 7c00: move $0000,%ax */
     [0x00] = 0xb8,
     [0x01] = 0x00,
     [0x02] = 0x00,
     /* 7c03: move %ax,%ds */
     [0x03] = 0x8e,
     [0x04] = 0xd8,
 
     /* 7c05: mov $0xdead,%ax */
     [0x05] = 0xb8,
     [0x06] = LOW(SIGNATURE),
     [0x07] = HIGH(SIGNATURE),
     /* 7c08:  mov %ax,0x7c10 */
     [0x08] = 0xa3,
     [0x09] = LOW(SIGNATURE_ADDR),
     [0x0a] = HIGH(SIGNATURE_ADDR),
 
     /* 7c0b cli */
     [0x0b] = 0xfa,
     /* 7c0c: hlt */
     [0x0c] = 0xf4,
     /* 7c0e: jmp 0x7c07=0x7c0f-3 */
     [0x0d] = 0xeb,
     [0x0e] = LOW(-3),
     /* We mov 0xdead here: set value to make debugging easier */
     [SIGNATURE_OFFSET] = LOW(0xface),
     [SIGNATURE_OFFSET + 1] = HIGH(0xface),
     /* End of boot sector marker */
     [0x1FE] = 0x55,
     [0x1FF] = 0xAA,
 };
 
 /* For s390x, use a mini "kernel" with the appropriate signature */
 static const uint8_t s390x_psw_and_magic[] = {
     0x00, 0x08, 0x00, 0x00, 0x80, 0x01, 0x00, 0x00,  /* Program status word  */
     0x02, 0x00, 0x00, 0x18, 0x60, 0x00, 0x00, 0x50,  /* Magic:               */
     0x02, 0x00, 0x00, 0x68, 0x60, 0x00, 0x00, 0x50,  /* see linux_s390_magic */
     0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40   /* in the s390-ccw bios */
 };
 static const uint8_t s390x_code[] = {
     0xa7, 0xf4, 0x00, 0x08,                                /* j 0x10010 */
     0x00, 0x00, 0x00, 0x00,
     'S', '3', '9', '0',
     'E', 'P', 0x00, 0x01,
     0xa7, 0x39, HIGH(SIGNATURE_ADDR), LOW(SIGNATURE_ADDR), /* lghi r3,0x7c10 */
     0xa7, 0x48, LOW(SIGNATURE), HIGH(SIGNATURE),           /* lhi r4,0xadde */
     0x40, 0x40, 0x30, 0x00,                                /* sth r4,0(r3) */
     0xa7, 0xf4, 0xff, 0xfa                                 /* j 0x10010 */
 };
 
 /* Create boot disk file.  */
 int boot_sector_init(char *fname)
 {
     int fd, ret;
     size_t len;
     char *boot_code;
     const char *arch = qtest_get_arch();
 
     fd = mkstemp(fname);
     if (fd < 0) {
         fprintf(stderr, "Couldn't open \"%s\": %s", fname, strerror(errno));
         return 1;
     }
 
     if (g_str_equal(arch, "i386") || g_str_equal(arch, "x86_64")) {
         /* Q35 requires a minimum 0x7e000 bytes disk (bug or feature?) */
         len = MAX(0x7e000, sizeof(x86_boot_sector));
         boot_code = g_malloc0(len);
         memcpy(boot_code, x86_boot_sector, sizeof(x86_boot_sector));
     } else if (g_str_equal(arch, "ppc64")) {
         /* For Open Firmware based system, use a Forth script */
         boot_code = g_strdup_printf("\\ Bootscript\n%x %x c! %x %x c!\n",
                                     LOW(SIGNATURE), SIGNATURE_ADDR,
                                     HIGH(SIGNATURE), SIGNATURE_ADDR + 1);
         len = strlen(boot_code);
     } else if (g_str_equal(arch, "s390x")) {
         len = 0x10000 + sizeof(s390x_code);
         boot_code = g_malloc0(len);
         memcpy(boot_code, s390x_psw_and_magic, sizeof(s390x_psw_and_magic));
         memcpy(&boot_code[0x10000], s390x_code, sizeof(s390x_code));
     } else {
         g_assert_not_reached();
     }
 
     ret = write(fd, boot_code, len);
     close(fd);
 
     g_free(boot_code);
 
     if (ret != len) {
         fprintf(stderr, "Could not write \"%s\"", fname);
         return 1;
     }
 
     return 0;
 }
 
 /* Loop until signature in memory is OK.  */
 void boot_sector_test(QTestState *qts)
 {
     uint8_t signature_low;
     uint8_t signature_high;
     uint16_t signature;
     QDict *qrsp, *qret;
     int i;
 
     /* Wait at most 600 seconds (test is slow with TCI and --enable-debug) */
 #define TEST_DELAY (1 * G_USEC_PER_SEC / 10)
 #define TEST_CYCLES MAX((600 * G_USEC_PER_SEC / TEST_DELAY), 1)
 
     /* Poll until code has run and modified memory.  Once it has we know BIOS
      * initialization is done.  TODO: check that IP reached the halt
      * instruction.
      */
     for (i = 0; i < TEST_CYCLES; ++i) {
         signature_low = qtest_readb(qts, SIGNATURE_ADDR);
         signature_high = qtest_readb(qts, SIGNATURE_ADDR + 1);
         signature = (signature_high << 8) | signature_low;
         if (signature == SIGNATURE) {
             break;
         }
 
         /* check that guest is still in "running" state and did not panic */
         qrsp = qtest_qmp(qts, "{ 'execute': 'query-status' }");
         qret = qdict_get_qdict(qrsp, "return");
         g_assert_nonnull(qret);
         g_assert_cmpstr(qdict_get_try_str(qret, "status"), ==, "running");
         qobject_unref(qrsp);
 
         g_usleep(TEST_DELAY);
     }
 
     g_assert_cmphex(signature, ==, SIGNATURE);
 }
 
 /* unlink boot disk file.  */
 void boot_sector_cleanup(const char *fname)
 {
     unlink(fname);
 }