pc.c

xen虚拟机源代码安装包

}

/* Generate an initial boot sector which sets state and jump to
   a specified vector */
static void generate_bootsect(uint32_t gpr[8], uint16_t segs[6], uint16_t ip)
{
    uint8_t bootsect[512], *p;
    int i;
    int hda;

    hda = drive_get_index(IF_IDE, 0, 0);
    if (hda == -1) {
	fprintf(stderr, "A disk image must be given for 'hda' when booting "
		"a Linux kernel\n");
	exit(1);
    }

    memset(bootsect, 0, sizeof(bootsect));

    /* Copy the MSDOS partition table if possible */
    bdrv_read(drives_table[hda].bdrv, 0, bootsect, 1);

    /* Make sure we have a partition signature */
    bootsect[510] = 0x55;
    bootsect[511] = 0xaa;

    /* Actual code */
    p = bootsect;
    *p++ = 0xfa;		/* CLI */
    *p++ = 0xfc;		/* CLD */

    for (i = 0; i < 6; i++) {
	if (i == 1)		/* Skip CS */
	    continue;

	*p++ = 0xb8;		/* MOV AX,imm16 */
	*p++ = segs[i];
	*p++ = segs[i] >> 8;
	*p++ = 0x8e;		/* MOV <seg>,AX */
	*p++ = 0xc0 + (i << 3);
    }

    for (i = 0; i < 8; i++) {
	*p++ = 0x66;		/* 32-bit operand size */
	*p++ = 0xb8 + i;	/* MOV <reg>,imm32 */
	*p++ = gpr[i];
	*p++ = gpr[i] >> 8;
	*p++ = gpr[i] >> 16;
	*p++ = gpr[i] >> 24;
    }

    *p++ = 0xea;		/* JMP FAR */
    *p++ = ip;			/* IP */
    *p++ = ip >> 8;
    *p++ = segs[1];		/* CS */
    *p++ = segs[1] >> 8;

    bdrv_set_boot_sector(drives_table[hda].bdrv, bootsect, sizeof(bootsect));
}

static long get_file_size(FILE *f)
{
    long where, size;

    /* XXX: on Unix systems, using fstat() probably makes more sense */

    where = ftell(f);
    fseek(f, 0, SEEK_END);
    size = ftell(f);
    fseek(f, where, SEEK_SET);

    return size;
}

static void pstrcpy_targphys(target_phys_addr_t dest, int buf_size,
			     const char *source)
{
    static const char nul_byte;
    const char *nulp;

    if (buf_size <= 0) return;
    nulp = memchr(source, 0, buf_size);
    if (nulp) {
	cpu_physical_memory_write(dest, source, (nulp - source) + 1);
    } else {
	cpu_physical_memory_write(dest, source, buf_size - 1);
	cpu_physical_memory_write(dest, &nul_byte, 1);
    }
}

static void load_linux(const char *kernel_filename,
		       const char *initrd_filename,
		       const char *kernel_cmdline)
{
#ifndef __ia64__
    uint16_t protocol;
    uint32_t gpr[8];
    uint16_t seg[6];
    uint16_t real_seg;
    int setup_size, kernel_size, initrd_size, cmdline_size;
    unsigned long end_low_ram;
    uint32_t initrd_max;
    uint8_t header[1024];
    target_phys_addr_t real_addr, prot_addr, cmdline_addr, initrd_addr;
    FILE *f, *fi;

    /* Align to 16 bytes as a paranoia measure */
    cmdline_size = (strlen(kernel_cmdline)+16) & ~15;

    /* load the kernel header */
    f = fopen(kernel_filename, "rb");
    if (!f || !(kernel_size = get_file_size(f)) ||
	fread(header, 1, 1024, f) != 1024) {
	fprintf(stderr, "qemu: could not load kernel '%s'\n",
		kernel_filename);
	exit(1);
    }

    /* kernel protocol version */
#if 0
    fprintf(stderr, "header magic: %#x\n", ldl_p(header+0x202));
#endif
    if (ldl_p(header+0x202) == 0x53726448)
	protocol = lduw_p(header+0x206);
    else
	protocol = 0;

    if (protocol < 0x200 || !(header[0x211] & 0x01)) {
	/* Low kernel */
	real_addr    = 0x90000;
	cmdline_addr = 0x9a000 - cmdline_size;
	prot_addr    = 0x10000;
    } else if (protocol < 0x202) {
	/* High but ancient kernel */
	real_addr    = 0x90000;
	cmdline_addr = 0x9a000 - cmdline_size;
	prot_addr    = 0x100000;
    } else {
	/* High and recent kernel */
	real_addr    = 0x10000;
	cmdline_addr = 0x20000;
	prot_addr    = 0x100000;
    }

#if 1
    fprintf(stderr,
	    "qemu: real_addr     = %#zx\n"
	    "qemu: cmdline_addr  = %#zx\n"
	    "qemu: prot_addr     = %#zx\n",
	    (size_t)real_addr,
	    (size_t)cmdline_addr,
	    (size_t)prot_addr);
#endif

    /* Special pages are placed at end of low RAM: pick an arbitrary one and
     * subtract a suitably large amount of padding (64kB) to skip BIOS data. */
    xc_get_hvm_param(xc_handle, domid, HVM_PARAM_BUFIOREQ_PFN, &end_low_ram);
    end_low_ram = (end_low_ram << 12) - (64*1024);

    /* highest address for loading the initrd */
    initrd_max = (protocol >= 0x203) ? ldl_p(header+0x22c) : 0x37ffffff;
    initrd_max = MIN(initrd_max, (uint32_t)end_low_ram);

    /* kernel command line */
    pstrcpy_targphys(cmdline_addr, 4096, kernel_cmdline);

    if (protocol >= 0x202) {
	stl_p(header+0x228, cmdline_addr);
    } else {
	stw_p(header+0x20, 0xA33F);
	stw_p(header+0x22, cmdline_addr-real_addr);
    }

    /* loader type */
    /* High nybble = B reserved for Qemu; low nybble is revision number.
       If this code is substantially changed, you may want to consider
       incrementing the revision. */
    if (protocol >= 0x200)
	header[0x210] = 0xB0;

    /* heap */
    if (protocol >= 0x201) {
	header[0x211] |= 0x80;	/* CAN_USE_HEAP */
	stw_p(header+0x224, cmdline_addr-real_addr-0x200);
    }

    /* load initrd */
    if (initrd_filename) {
	if (protocol < 0x200) {
	    fprintf(stderr, "qemu: linux kernel too old to load a ram disk\n");
	    exit(1);
	}

	fi = fopen(initrd_filename, "rb");
	if (!fi) {
	    fprintf(stderr, "qemu: could not load initial ram disk '%s'\n",
		    initrd_filename);
	    exit(1);
	}

	initrd_size = get_file_size(fi);
	initrd_addr = ((initrd_max-initrd_size) & ~4095);

	fprintf(stderr, "qemu: loading initrd (%#x bytes) at %#zx\n",
		initrd_size, (size_t)initrd_addr);

	if (!fread_targphys_ok(initrd_addr, initrd_size, fi)) {
	    fprintf(stderr, "qemu: read error on initial ram disk '%s'\n",
		    initrd_filename);
	    exit(1);
	}
	fclose(fi);

	stl_p(header+0x218, initrd_addr);
	stl_p(header+0x21c, initrd_size);
    }

    /* store the finalized header and load the rest of the kernel */
    cpu_physical_memory_write(real_addr, header, 1024);

    setup_size = header[0x1f1];
    if (setup_size == 0)
	setup_size = 4;

    setup_size = (setup_size+1)*512;
    kernel_size -= setup_size;	/* Size of protected-mode code */

    xen_relocator_hook(&prot_addr, protocol, header, kernel_size,
		       real_addr, setup_size-1024);

    if (!fread_targphys_ok(real_addr+1024, setup_size-1024, f) ||
	!fread_targphys_ok(prot_addr, kernel_size, f)) {
	fprintf(stderr, "qemu: read error on kernel '%s'\n",
		kernel_filename);
	exit(1);
    }
    fclose(f);

    /* generate bootsector to set up the initial register state */
    real_seg = real_addr >> 4;
    seg[0] = seg[2] = seg[3] = seg[4] = seg[4] = real_seg;
    seg[1] = real_seg+0x20;	/* CS */
    memset(gpr, 0, sizeof gpr);
    gpr[4] = cmdline_addr-real_addr-16;	/* SP (-16 is paranoia) */

    generate_bootsect(gpr, seg, 0);
#endif
}

static void main_cpu_reset(void *opaque)
{
    CPUState *env = opaque;
    cpu_reset(env);
}

static const int ide_iobase[2] = { 0x1f0, 0x170 };
static const int ide_iobase2[2] = { 0x3f6, 0x376 };
static const int ide_irq[2] = { 14, 15 };

#define NE2000_NB_MAX 6

static int ne2000_io[NE2000_NB_MAX] = { 0x300, 0x320, 0x340, 0x360, 0x280, 0x380 };
static int ne2000_irq[NE2000_NB_MAX] = { 9, 10, 11, 3, 4, 5 };

static int serial_io[MAX_SERIAL_PORTS] = { 0x3f8, 0x2f8, 0x3e8, 0x2e8 };
static int serial_irq[MAX_SERIAL_PORTS] = { 4, 3, 4, 3 };

static int parallel_io[MAX_PARALLEL_PORTS] = { 0x378, 0x278, 0x3bc };
static int parallel_irq[MAX_PARALLEL_PORTS] = { 7, 7, 7 };

#ifdef HAS_AUDIO
static void audio_init (PCIBus *pci_bus, qemu_irq *pic)
{
    struct soundhw *c;
    int audio_enabled = 0;

    for (c = soundhw; !audio_enabled && c->name; ++c) {
        audio_enabled = c->enabled;
    }

    if (audio_enabled) {
        AudioState *s;

        s = AUD_init ();
        if (s) {
            for (c = soundhw; c->name; ++c) {
                if (c->enabled) {
                    if (c->isa) {
                        c->init.init_isa (s, pic);
                    }
                    else {
                        if (pci_bus) {
                            c->init.init_pci (pci_bus, s);
                        }
                    }
                }
            }
        }
    }
}
#endif

static void pc_init_ne2k_isa(NICInfo *nd, qemu_irq *pic)
{
    static int nb_ne2k = 0;

    if (nb_ne2k == NE2000_NB_MAX)
        return;
    isa_ne2000_init(ne2000_io[nb_ne2k], pic[ne2000_irq[nb_ne2k]], nd);
    nb_ne2k++;
}

/* PC hardware initialisation */
static void pc_init1(ram_addr_t ram_size, int vga_ram_size,
                     const char *boot_device, DisplayState *ds,
                     const char *kernel_filename, const char *kernel_cmdline,
                     const char *initrd_filename,
                     int pci_enabled, const char *cpu_model,
		     const char *direct_pci)
{
    char buf[1024];
    int ret, linux_boot, i;
    ram_addr_t ram_addr, vga_ram_addr, bios_offset, vga_bios_offset;
    ram_addr_t below_4g_mem_size, above_4g_mem_size = 0;
    int bios_size, isa_bios_size, vga_bios_size;
    PCIBus *pci_bus;
    int piix3_devfn = -1;
    CPUState *env;
    NICInfo *nd;
    qemu_irq *cpu_irq;
    qemu_irq *i8259;
    int index;
    BlockDriverState *hd[MAX_IDE_BUS * MAX_IDE_DEVS];
    BlockDriverState *fd[MAX_FD];
    int rc;

    if (ram_size >= 0xe0000000 ) {
        above_4g_mem_size = ram_size - 0xe0000000;
        below_4g_mem_size = 0xe0000000;
    } else {
        below_4g_mem_size = ram_size;
    }

    qemu_register_boot_set(pc_boot_set);

    linux_boot = (kernel_filename != NULL);

    /* init CPUs */
    if (cpu_model == NULL) {
#ifdef TARGET_X86_64
        cpu_model = "qemu64";
#else
        cpu_model = "qemu32";
#endif
    }
    
    for(i = 0; i < smp_cpus; i++) {
        env = cpu_init(cpu_model);
        if (!env) {
            fprintf(stderr, "Unable to find x86 CPU definition\n");
            exit(1);
        }
#ifndef CONFIG_DM
        if (i != 0)
            env->hflags |= HF_HALTED_MASK;
        if (smp_cpus > 1) {
            /* XXX: enable it in all cases */
            env->cpuid_features |= CPUID_APIC;
        }
#endif /* !CONFIG_DM */
        register_savevm("cpu", i, 4, cpu_save, cpu_load, env);
        qemu_register_reset(main_cpu_reset, env);
        if (pci_enabled) {
            apic_init(env);
        }
    }

    vmport_init();

#ifndef CONFIG_DM
    /* allocate RAM */
    ram_addr = qemu_ram_alloc(ram_size);
    cpu_register_physical_memory(0, below_4g_mem_size, ram_addr);

    /* above 4giga memory allocation */
    if (above_4g_mem_size > 0) {
        cpu_register_physical_memory(0x100000000ULL, above_4g_mem_size,
                                     ram_addr + below_4g_mem_size);
    }

    /* allocate VGA RAM */
    vga_ram_addr = qemu_ram_alloc(vga_ram_size);

    /* BIOS load */
    if (bios_name == NULL)
        bios_name = BIOS_FILENAME;
    snprintf(buf, sizeof(buf), "%s/%s", bios_dir, bios_name);
    bios_size = get_image_size(buf);
    if (bios_size <= 0 ||
        (bios_size % 65536) != 0) {
        goto bios_error;
    }
    bios_offset = qemu_ram_alloc(bios_size);
    ret = load_image_targphys(buf, bios_offset, bios_size);
    if (ret != bios_size) {
    bios_error:
        fprintf(stderr, "qemu: could not load PC BIOS '%s'\n", buf);
        exit(1);
    }

    /* VGA BIOS load */
    if (cirrus_vga_enabled) {
        snprintf(buf, sizeof(buf), "%s/%s", bios_dir, VGABIOS_CIRRUS_FILENAME);
    } else {
        snprintf(buf, sizeof(buf), "%s/%s", bios_dir, VGABIOS_FILENAME);
    }
    vga_bios_size = get_image_size(buf);
    if (vga_bios_size <= 0 || vga_bios_size > 65536)
        goto vga_bios_error;
    vga_bios_offset = qemu_ram_alloc(65536);

    ret = load_image_targphys(buf, vga_bios_offset, vga_bios_size);
    if (ret != vga_bios_size) {
    vga_bios_error:
        fprintf(stderr, "qemu: could not load VGA BIOS '%s'\n", buf);
        exit(1);
    }

    /* setup basic memory access */
    cpu_register_physical_memory(0xc0000, 0x10000,
                                 vga_bios_offset | IO_MEM_ROM);

    /* map the last 128KB of the BIOS in ISA space */
    isa_bios_size = bios_size;
    if (isa_bios_size > (128 * 1024))