hw/xenpv/xen_domainbuild.c

   1 #include "qemu/osdep.h"
   2 #include "hw/xen/xen_backend.h"
   3 #include "xen_domainbuild.h"
   4 #include "qemu/timer.h"
   5 #include "qemu/log.h"
   6
   7 #include <xenguest.h>
   8
   9 static int xenstore_domain_mkdir(char *path)
  10 {
  11     struct xs_permissions perms_ro[] = {{
  12             .id    = 0, /* set owner: dom0 */
  13         },{
  14             .id    = xen_domid,
  15             .perms = XS_PERM_READ,
  16         }};
  17     struct xs_permissions perms_rw[] = {{
  18             .id    = 0, /* set owner: dom0 */
  19         },{
  20             .id    = xen_domid,
  21             .perms = XS_PERM_READ | XS_PERM_WRITE,
  22         }};
  23     const char *writable[] = { "device", "control", "error", NULL };
  24     char subpath[256];
  25     int i;
  26
  27     if (!xs_mkdir(xenstore, 0, path)) {
  28         fprintf(stderr, "%s: xs_mkdir %s: failed\n", __func__, path);
  29         return -1;
  30     }
  31     if (!xs_set_permissions(xenstore, 0, path, perms_ro, 2)) {
  32         fprintf(stderr, "%s: xs_set_permissions failed\n", __func__);
  33         return -1;
  34     }
  35
  36     for (i = 0; writable[i]; i++) {
  37         snprintf(subpath, sizeof(subpath), "%s/%s", path, writable[i]);
  38         if (!xs_mkdir(xenstore, 0, subpath)) {
  39             fprintf(stderr, "%s: xs_mkdir %s: failed\n", __func__, subpath);
  40             return -1;
  41         }
  42         if (!xs_set_permissions(xenstore, 0, subpath, perms_rw, 2)) {
  43             fprintf(stderr, "%s: xs_set_permissions failed\n", __func__);
  44             return -1;
  45         }
  46     }
  47     return 0;
  48 }
  49
  50 int xenstore_domain_init1(const char *kernel, const char *ramdisk,
  51                           const char *cmdline)
  52 {
  53     char *dom, uuid_string[42], vm[256], path[256];
  54     int i;
  55
  56     qemu_uuid_unparse(&qemu_uuid, uuid_string);
  57     dom = xs_get_domain_path(xenstore, xen_domid);
  58     snprintf(vm,  sizeof(vm),  "/vm/%s", uuid_string);
  59
  60     xenstore_domain_mkdir(dom);
  61
  62     xenstore_write_str(vm, "image/ostype",  "linux");
  63     if (kernel)
  64         xenstore_write_str(vm, "image/kernel",  kernel);
  65     if (ramdisk)
  66         xenstore_write_str(vm, "image/ramdisk", ramdisk);
  67     if (cmdline)
  68         xenstore_write_str(vm, "image/cmdline", cmdline);
  69
  70     /* name + id */
  71     xenstore_write_str(vm,  "name",   qemu_name ? qemu_name : "no-name");
  72     xenstore_write_str(vm,  "uuid",   uuid_string);
  73     xenstore_write_str(dom, "name",   qemu_name ? qemu_name : "no-name");
  74     xenstore_write_int(dom, "domid",  xen_domid);
  75     xenstore_write_str(dom, "vm",     vm);
  76
  77     /* memory */
  78     xenstore_write_int(dom, "memory/target", ram_size >> 10);  // kB
  79     xenstore_write_int(vm, "memory",         ram_size >> 20);  // MB
  80     xenstore_write_int(vm, "maxmem",         ram_size >> 20);  // MB
  81
  82     /* cpus */
  83     for (i = 0; i < smp_cpus; i++) {
  84         snprintf(path, sizeof(path), "cpu/%d/availability",i);
  85         xenstore_write_str(dom, path, "online");
  86     }
  87     xenstore_write_int(vm, "vcpu_avail",  smp_cpus);
  88     xenstore_write_int(vm, "vcpus",       smp_cpus);
  89
  90     /* vnc password */
  91     xenstore_write_str(vm, "vncpassword", "" /* FIXME */);
  92
  93     free(dom);
  94     return 0;
  95 }
  96
  97 int xenstore_domain_init2(int xenstore_port, int xenstore_mfn,
  98                           int console_port, int console_mfn)
  99 {
 100     char *dom;
 101
 102     dom = xs_get_domain_path(xenstore, xen_domid);
 103
 104     /* signal new domain */
 105     xs_introduce_domain(xenstore,
 106                         xen_domid,
 107                         xenstore_mfn,
 108                         xenstore_port);
 109
 110     /* xenstore */
 111     xenstore_write_int(dom, "store/ring-ref",   xenstore_mfn);
 112     xenstore_write_int(dom, "store/port",       xenstore_port);
 113
 114     /* console */
 115     xenstore_write_str(dom, "console/type",     "ioemu");
 116     xenstore_write_int(dom, "console/limit",    128 * 1024);
 117     xenstore_write_int(dom, "console/ring-ref", console_mfn);
 118     xenstore_write_int(dom, "console/port",     console_port);
 119     xen_config_dev_console(0);
 120
 121     free(dom);
 122     return 0;
 123 }
 124
 125 /* ------------------------------------------------------------- */
 126
 127 static QEMUTimer *xen_poll;
 128
 129 /* check domain state once per second */
 130 static void xen_domain_poll(void *opaque)
 131 {
 132     struct xc_dominfo info;
 133     int rc;
 134
 135     rc = xc_domain_getinfo(xen_xc, xen_domid, 1, &info);
 136     if ((rc != 1) || (info.domid != xen_domid)) {
 137         qemu_log("xen: domain %d is gone\n", xen_domid);
 138         goto quit;
 139     }
 140     if (info.dying) {
 141         qemu_log("xen: domain %d is dying (%s%s)\n", xen_domid,
 142                  info.crashed  ? "crashed"  : "",
 143                  info.shutdown ? "shutdown" : "");
 144         goto quit;
 145     }
 146
 147     timer_mod(xen_poll, qemu_clock_get_ms(QEMU_CLOCK_REALTIME) + 1000);
 148     return;
 149
 150 quit:
 151     qemu_system_shutdown_request(SHUTDOWN_CAUSE_GUEST_SHUTDOWN);
 152 }
 153
 154 static int xen_domain_watcher(void)
 155 {
 156     int qemu_running = 1;
 157     int fd[2], i, n, rc;
 158     char byte;
 159
 160     if (pipe(fd) != 0) {
 161         qemu_log("%s: Huh? pipe error: %s\n", __func__, strerror(errno));
 162         return -1;
 163     }
 164     if (fork() != 0)
 165         return 0; /* not child */
 166
 167     /* close all file handles, except stdio/out/err,
 168      * our watch pipe and the xen interface handle */
 169     n = getdtablesize();
 170     for (i = 3; i < n; i++) {
 171         if (i == fd[0])
 172             continue;
 173         close(i);
 174     }
 175
 176     /*
 177      * Reopen xc interface, since the original is unsafe after fork
 178      * and was closed above.
 179      */
 180     xen_xc = xc_interface_open(0, 0, 0);
 181
 182     /* ignore term signals */
 183     signal(SIGINT,  SIG_IGN);
 184     signal(SIGTERM, SIG_IGN);
 185
 186     /* wait for qemu exiting */
 187     while (qemu_running) {
 188         rc = read(fd[0], &byte, 1);
 189         switch (rc) {
 190         case -1:
 191             if (errno == EINTR)
 192                 continue;
 193             qemu_log("%s: Huh? read error: %s\n", __func__, strerror(errno));
 194             qemu_running = 0;
 195             break;
 196         case 0:
 197             /* EOF -> qemu exited */
 198             qemu_running = 0;
 199             break;
 200         default:
 201             qemu_log("%s: Huh? data on the watch pipe?\n", __func__);
 202             break;
 203         }
 204     }
 205
 206     /* cleanup */
 207     qemu_log("%s: destroy domain %d\n", __func__, xen_domid);
 208     xc_domain_destroy(xen_xc, xen_domid);
 209     _exit(0);
 210 }
 211
 212 /* normal cleanup */
 213 static void xen_domain_cleanup(void)
 214 {
 215     char *dom;
 216
 217     dom = xs_get_domain_path(xenstore, xen_domid);
 218     if (dom) {
 219         xs_rm(xenstore, 0, dom);
 220         free(dom);
 221     }
 222     xs_release_domain(xenstore, xen_domid);
 223 }
 224
 225 int xen_domain_build_pv(const char *kernel, const char *ramdisk,
 226                         const char *cmdline)
 227 {
 228     uint32_t ssidref = 0;
 229     uint32_t flags = 0;
 230     xen_domain_handle_t uuid;
 231     unsigned int xenstore_port = 0, console_port = 0;
 232     unsigned long xenstore_mfn = 0, console_mfn = 0;
 233     int rc;
 234
 235     memcpy(uuid, &qemu_uuid, sizeof(uuid));
 236     rc = xen_domain_create(xen_xc, ssidref, uuid, flags, &xen_domid);
 237     if (rc < 0) {
 238         fprintf(stderr, "xen: xc_domain_create() failed\n");
 239         goto err;
 240     }
 241     qemu_log("xen: created domain %d\n", xen_domid);
 242     atexit(xen_domain_cleanup);
 243     if (xen_domain_watcher() == -1) {
 244         goto err;
 245     }
 246
 247     xenstore_domain_init1(kernel, ramdisk, cmdline);
 248
 249     rc = xc_domain_max_vcpus(xen_xc, xen_domid, smp_cpus);
 250     if (rc < 0) {
 251         fprintf(stderr, "xen: xc_domain_max_vcpus() failed\n");
 252         goto err;
 253     }
 254
 255 #if 0
 256     rc = xc_domain_setcpuweight(xen_xc, xen_domid, 256);
 257     if (rc < 0) {
 258         fprintf(stderr, "xen: xc_domain_setcpuweight() failed\n");
 259         goto err;
 260     }
 261 #endif
 262
 263     rc = xc_domain_setmaxmem(xen_xc, xen_domid, ram_size >> 10);
 264     if (rc < 0) {
 265         fprintf(stderr, "xen: xc_domain_setmaxmem() failed\n");
 266         goto err;
 267     }
 268
 269     xenstore_port = xc_evtchn_alloc_unbound(xen_xc, xen_domid, 0);
 270     console_port = xc_evtchn_alloc_unbound(xen_xc, xen_domid, 0);
 271
 272     rc = xc_linux_build(xen_xc, xen_domid, ram_size >> 20,
 273                         kernel, ramdisk, cmdline,
 274                         0, flags,
 275                         xenstore_port, &xenstore_mfn,
 276                         console_port, &console_mfn);
 277     if (rc < 0) {
 278         fprintf(stderr, "xen: xc_linux_build() failed\n");
 279         goto err;
 280     }
 281
 282     xenstore_domain_init2(xenstore_port, xenstore_mfn,
 283                           console_port, console_mfn);
 284
 285     qemu_log("xen: unpausing domain %d\n", xen_domid);
 286     rc = xc_domain_unpause(xen_xc, xen_domid);
 287     if (rc < 0) {
 288         fprintf(stderr, "xen: xc_domain_unpause() failed\n");
 289         goto err;
 290     }
 291
 292     xen_poll = timer_new_ms(QEMU_CLOCK_REALTIME, xen_domain_poll, NULL);
 293     timer_mod(xen_poll, qemu_clock_get_ms(QEMU_CLOCK_REALTIME) + 1000);
 294     return 0;
 295
 296 err:
 297     return -1;
 298 }