Archipelago » qemu

#include <signal.h>

#include "xen_backend.h"

#include "xen_domainbuild.h"

#include "sysemu.h"

#include "qemu-timer.h"

#include <xenguest.h>

static int xenstore_domain_mkdir(char *path)

{

    struct xs_permissions perms_ro[] = {{

            .id    = 0, /* set owner: dom0 */

        },{

            .id    = xen_domid,

            .perms = XS_PERM_READ,

        }};

    struct xs_permissions perms_rw[] = {{

            .id    = 0, /* set owner: dom0 */

        },{

            .id    = xen_domid,

            .perms = XS_PERM_READ | XS_PERM_WRITE,

        }};

    const char *writable[] = { "device", "control", "error", NULL };

    char subpath[256];

    int i;

    if (!xs_mkdir(xenstore, 0, path)) {

        fprintf(stderr, "%s: xs_mkdir %s: failed\n", __FUNCTION__, path);

        return -1;

    }

    if (!xs_set_permissions(xenstore, 0, path, perms_ro, 2)) {

        fprintf(stderr, "%s: xs_set_permissions failed\n", __FUNCTION__);

        return -1;

    }

    for (i = 0; writable[i]; i++) {

        snprintf(subpath, sizeof(subpath), "%s/%s", path, writable[i]);

        if (!xs_mkdir(xenstore, 0, subpath)) {

            fprintf(stderr, "%s: xs_mkdir %s: failed\n", __FUNCTION__, subpath);

            return -1;

        }

        if (!xs_set_permissions(xenstore, 0, subpath, perms_rw, 2)) {

            fprintf(stderr, "%s: xs_set_permissions failed\n", __FUNCTION__);

            return -1;

        }

    }

    return 0;

}

int xenstore_domain_init1(const char *kernel, const char *ramdisk,

                          const char *cmdline)

{

    char *dom, uuid_string[42], vm[256], path[256];

    int i;

    snprintf(uuid_string, sizeof(uuid_string), UUID_FMT,

             qemu_uuid[0], qemu_uuid[1], qemu_uuid[2], qemu_uuid[3],

             qemu_uuid[4], qemu_uuid[5], qemu_uuid[6], qemu_uuid[7],

             qemu_uuid[8], qemu_uuid[9], qemu_uuid[10], qemu_uuid[11],

             qemu_uuid[12], qemu_uuid[13], qemu_uuid[14], qemu_uuid[15]);

    dom = xs_get_domain_path(xenstore, xen_domid);

    snprintf(vm,  sizeof(vm),  "/vm/%s", uuid_string);

    xenstore_domain_mkdir(dom);

    xenstore_write_str(vm, "image/ostype",  "linux");

    if (kernel)

        xenstore_write_str(vm, "image/kernel",  kernel);

    if (ramdisk)

        xenstore_write_str(vm, "image/ramdisk", ramdisk);

    if (cmdline)

        xenstore_write_str(vm, "image/cmdline", cmdline);

    /* name + id */

    xenstore_write_str(vm,  "name",   qemu_name ? qemu_name : "no-name");

    xenstore_write_str(vm,  "uuid",   uuid_string);

    xenstore_write_str(dom, "name",   qemu_name ? qemu_name : "no-name");

    xenstore_write_int(dom, "domid",  xen_domid);

    xenstore_write_str(dom, "vm",     vm);

    /* memory */

    xenstore_write_int(dom, "memory/target", ram_size >> 10);  // kB

    xenstore_write_int(vm, "memory",         ram_size >> 20);  // MB

    xenstore_write_int(vm, "maxmem",         ram_size >> 20);  // MB

    /* cpus */

    for (i = 0; i < smp_cpus; i++) {

        snprintf(path, sizeof(path), "cpu/%d/availability",i);

        xenstore_write_str(dom, path, "online");

    }

    xenstore_write_int(vm, "vcpu_avail",  smp_cpus);

    xenstore_write_int(vm, "vcpus",       smp_cpus);

    /* vnc password */

    xenstore_write_str(vm, "vncpassword", "" /* FIXME */);

    free(dom);

    return 0;

}

int xenstore_domain_init2(int xenstore_port, int xenstore_mfn,

                          int console_port, int console_mfn)

{

    char *dom;

    dom = xs_get_domain_path(xenstore, xen_domid);

    /* signal new domain */

    xs_introduce_domain(xenstore,

                        xen_domid,

                        xenstore_mfn,

                        xenstore_port);

    /* xenstore */

    xenstore_write_int(dom, "store/ring-ref",   xenstore_mfn);

    xenstore_write_int(dom, "store/port",       xenstore_port);

    /* console */

    xenstore_write_str(dom, "console/type",     "ioemu");

    xenstore_write_int(dom, "console/limit",    128 * 1024);

    xenstore_write_int(dom, "console/ring-ref", console_mfn);

    xenstore_write_int(dom, "console/port",     console_port);

    xen_config_dev_console(0);

    free(dom);

    return 0;

}

/* ------------------------------------------------------------- */

static QEMUTimer *xen_poll;

/* check domain state once per second */

static void xen_domain_poll(void *opaque)

{

    struct xc_dominfo info;

    int rc;

    rc = xc_domain_getinfo(xen_xc, xen_domid, 1, &info);

    if ((rc != 1) || (info.domid != xen_domid)) {

        qemu_log("xen: domain %d is gone\n", xen_domid);

        goto quit;

    }

    if (info.dying) {

        qemu_log("xen: domain %d is dying (%s%s)\n", xen_domid,

                 info.crashed  ? "crashed"  : "",

                 info.shutdown ? "shutdown" : "");

        goto quit;

    }

    qemu_mod_timer(xen_poll, qemu_get_clock(rt_clock) + 1000);

    return;

quit:

    qemu_system_shutdown_request();

    return;

}

static void xen_domain_watcher(void)

{

    int qemu_running = 1;

    int fd[2], i, n, rc;

    char byte;

    pipe(fd);

    if (fork() != 0)

        return; /* not child */

    /* close all file handles, except stdio/out/err,

     * our watch pipe and the xen interface handle */

    n = getdtablesize();

    for (i = 3; i < n; i++) {

        if (i == fd[0])

            continue;

        if (i == xen_xc)

            continue;

        close(i);

    }

    /* ignore term signals */

    signal(SIGINT,  SIG_IGN);

    signal(SIGTERM, SIG_IGN);

    /* wait for qemu exiting */

    while (qemu_running) {

        rc = read(fd[0], &byte, 1);

        switch (rc) {

        case -1:

            if (errno == EINTR)

                continue;

            qemu_log("%s: Huh? read error: %s\n", __FUNCTION__, strerror(errno));

            qemu_running = 0;

            break;

        case 0:

            /* EOF -> qemu exited */

            qemu_running = 0;

            break;

        default:

            qemu_log("%s: Huh? data on the watch pipe?\n", __FUNCTION__);

            break;

        }

    }

    /* cleanup */

    qemu_log("%s: destroy domain %d\n", __FUNCTION__, xen_domid);

    xc_domain_destroy(xen_xc, xen_domid);

    _exit(0);

}

/* normal cleanup */

static void xen_domain_cleanup(void)

{

    char *dom;

    dom = xs_get_domain_path(xenstore, xen_domid);

    if (dom) {

        xs_rm(xenstore, 0, dom);

        free(dom);

    }

    xs_release_domain(xenstore, xen_domid);

}

int xen_domain_build_pv(const char *kernel, const char *ramdisk,

                        const char *cmdline)

{

    uint32_t ssidref = 0;

    uint32_t flags = 0;

    xen_domain_handle_t uuid;

    unsigned int xenstore_port = 0, console_port = 0;

    unsigned long xenstore_mfn = 0, console_mfn = 0;

    int rc;

    memcpy(uuid, qemu_uuid, sizeof(uuid));

    rc = xc_domain_create(xen_xc, ssidref, uuid, flags, &xen_domid);

    if (rc < 0) {

        fprintf(stderr, "xen: xc_domain_create() failed\n");

        goto err;

    }

    qemu_log("xen: created domain %d\n", xen_domid);

    atexit(xen_domain_cleanup);

    xen_domain_watcher();

    xenstore_domain_init1(kernel, ramdisk, cmdline);

    rc = xc_domain_max_vcpus(xen_xc, xen_domid, smp_cpus);

    if (rc < 0) {

        fprintf(stderr, "xen: xc_domain_max_vcpus() failed\n");

        goto err;

    }

#if 0

    rc = xc_domain_setcpuweight(xen_xc, xen_domid, 256);

    if (rc < 0) {

        fprintf(stderr, "xen: xc_domain_setcpuweight() failed\n");

        goto err;

    }

#endif

    rc = xc_domain_setmaxmem(xen_xc, xen_domid, ram_size >> 10);

    if (rc < 0) {

        fprintf(stderr, "xen: xc_domain_setmaxmem() failed\n");

        goto err;

    }

    xenstore_port = xc_evtchn_alloc_unbound(xen_xc, xen_domid, 0);

    console_port = xc_evtchn_alloc_unbound(xen_xc, xen_domid, 0);

    rc = xc_linux_build(xen_xc, xen_domid, ram_size >> 20,

                        kernel, ramdisk, cmdline,

                        0, flags,

                        xenstore_port, &xenstore_mfn,

                        console_port, &console_mfn);

    if (rc < 0) {

        fprintf(stderr, "xen: xc_linux_build() failed\n");

        goto err;

    }

    xenstore_domain_init2(xenstore_port, xenstore_mfn,

                          console_port, console_mfn);

    qemu_log("xen: unpausing domain %d\n", xen_domid);

    rc = xc_domain_unpause(xen_xc, xen_domid);

    if (rc < 0) {

        fprintf(stderr, "xen: xc_domain_unpause() failed\n");

        goto err;

    }

    xen_poll = qemu_new_timer(rt_clock, xen_domain_poll, NULL);

    qemu_mod_timer(xen_poll, qemu_get_clock(rt_clock) + 1000);

    return 0;

err:

    return -1;

}