git.ozlabs.org Git - petitboot/blob - discover/boot.c

   1
   2 #if defined(HAVE_CONFIG_H)
   3 #include "config.h"
   4 #endif
   5
   6 #include <stdbool.h>
   7 #include <stdlib.h>
   8 #include <assert.h>
   9 #include <dirent.h>
  10 #include <string.h>
  11 #include <fcntl.h>
  12 #include <sys/types.h>
  13
  14 #include <log/log.h>
  15 #include <pb-protocol/pb-protocol.h>
  16 #include <process/process.h>
  17 #include <system/system.h>
  18 #include <talloc/talloc.h>
  19 #include <url/url.h>
  20 #include <util/util.h>
  21 #include <i18n/i18n.h>
  22
  23 #include "device-handler.h"
  24 #include "boot.h"
  25 #include "paths.h"
  26 #include "resource.h"
  27
  28 static const char *boot_hook_dir = PKG_SYSCONF_DIR "/boot.d";
  29 enum {
  30         BOOT_HOOK_EXIT_OK       = 0,
  31         BOOT_HOOK_EXIT_UPDATE   = 2,
  32 };
  33
  34 struct boot_task {
  35         struct load_url_result *image;
  36         struct load_url_result *initrd;
  37         struct load_url_result *dtb;
  38         const char *local_image;
  39         const char *local_initrd;
  40         const char *local_dtb;
  41         const char *args;
  42         boot_status_fn status_fn;
  43         void *status_arg;
  44         bool dry_run;
  45         bool cancelled;
  46 };
  47
  48 /**
  49  * kexec_load - kexec load helper.
  50  */
  51 static int kexec_load(struct boot_task *boot_task)
  52 {
  53         int result;
  54         const char *argv[7];
  55         const char **p;
  56         char *s_initrd = NULL;
  57         char *s_dtb = NULL;
  58         char *s_args = NULL;
  59
  60         p = argv;
  61         *p++ = pb_system_apps.kexec;    /* 1 */
  62         *p++ = "-l";                    /* 2 */
  63
  64         if (boot_task->local_initrd) {
  65                 s_initrd = talloc_asprintf(boot_task, "--initrd=%s",
  66                                 boot_task->local_initrd);
  67                 assert(s_initrd);
  68                 *p++ = s_initrd;         /* 3 */
  69         }
  70
  71         if (boot_task->local_dtb) {
  72                 s_dtb = talloc_asprintf(boot_task, "--dtb=%s",
  73                                                 boot_task->local_dtb);
  74                 assert(s_dtb);
  75                 *p++ = s_dtb;            /* 4 */
  76         }
  77
  78         if (boot_task->args) {
  79                 s_args = talloc_asprintf(boot_task, "--append=%s",
  80                                                 boot_task->args);
  81                 assert(s_args);
  82                 *p++ = s_args;          /* 5 */
  83         }
  84
  85         *p++ = boot_task->local_image;  /* 6 */
  86         *p++ = NULL;                    /* 7 */
  87
  88         result = process_run_simple_argv(boot_task, argv);
  89
  90         if (result)
  91                 pb_log("%s: failed: (%d)\n", __func__, result);
  92
  93         return result;
  94 }
  95
  96 /**
  97  * kexec_reboot - Helper to boot the new kernel.
  98  *
  99  * Must only be called after a successful call to kexec_load().
 100  */
 101
 102 static int kexec_reboot(struct boot_task *task)
 103 {
 104         int result;
 105
 106         /* First try running shutdown.  Init scripts should run 'exec -e' */
 107         result = process_run_simple(task, pb_system_apps.shutdown, "-r",
 108                         "now", NULL);
 109
 110         /* On error, force a kexec with the -e option */
 111         if (result) {
 112                 result = process_run_simple(task, pb_system_apps.kexec,
 113                                                 "-e", NULL);
 114         }
 115
 116         if (result)
 117                 pb_log("%s: failed: (%d)\n", __func__, result);
 118
 119         /* okay, kexec -e -f */
 120         if (result) {
 121                 result = process_run_simple(task, pb_system_apps.kexec,
 122                                                 "-e", "-f", NULL);
 123         }
 124
 125         if (result)
 126                 pb_log("%s: failed: (%d)\n", __func__, result);
 127
 128
 129         return result;
 130 }
 131
 132 static void __attribute__((format(__printf__, 4, 5))) update_status(
 133                 boot_status_fn fn, void *arg, int type, char *fmt, ...)
 134 {
 135         struct boot_status status;
 136         va_list ap;
 137
 138         va_start(ap, fmt);
 139         status.message = talloc_vasprintf(NULL, fmt, ap);
 140         va_end(ap);
 141
 142         status.type = type;
 143         status.progress = -1;
 144         status.detail = NULL;
 145
 146         pb_debug("boot status: [%d] %s\n", type, status.message);
 147
 148         fn(arg, &status);
 149
 150         talloc_free(status.message);
 151 }
 152
 153 static void boot_hook_update_param(void *ctx, struct boot_task *task,
 154                 const char *name, const char *value)
 155 {
 156         struct p {
 157                 const char *name;
 158                 const char **p;
 159         } *param, params[] = {
 160                 { "boot_image",         &task->local_image },
 161                 { "boot_initrd",        &task->local_initrd },
 162                 { "boot_dtb",           &task->local_dtb },
 163                 { "boot_args",          &task->args },
 164                 { NULL, NULL },
 165         };
 166
 167         for (param = params; param->name; param++) {
 168                 if (strcmp(param->name, name))
 169                         continue;
 170
 171                 *param->p = talloc_strdup(ctx, value);
 172                 return;
 173         }
 174 }
 175
 176 static void boot_hook_update(struct boot_task *task, const char *hookname,
 177                 char *buf)
 178 {
 179         char *line, *name, *val, *sep;
 180         char *saveptr = NULL;
 181
 182         for (;; buf = NULL) {
 183
 184                 line = strtok_r(buf, "\n", &saveptr);
 185                 if (!line)
 186                         break;
 187
 188                 sep = strchr(line, '=');
 189                 if (!sep)
 190                         continue;
 191
 192                 *sep = '\0';
 193                 name = line;
 194                 val = sep + 1;
 195
 196                 boot_hook_update_param(task, task, name, val);
 197
 198                 pb_log("boot hook %s specified %s=%s\n",
 199                                 hookname, name, val);
 200         }
 201 }
 202
 203 static void boot_hook_setenv(struct boot_task *task)
 204 {
 205         unsetenv("boot_image");
 206         unsetenv("boot_initrd");
 207         unsetenv("boot_dtb");
 208         unsetenv("boot_args");
 209
 210         setenv("boot_image", task->local_image, 1);
 211         if (task->local_initrd)
 212                 setenv("boot_initrd", task->local_initrd, 1);
 213         if (task->local_dtb)
 214                 setenv("boot_dtb", task->local_dtb, 1);
 215         if (task->args)
 216                 setenv("boot_args", task->args, 1);
 217 }
 218
 219 static int hook_filter(const struct dirent *dirent)
 220 {
 221         return dirent->d_type == DT_REG || dirent->d_type == DT_LNK;
 222 }
 223
 224 static int hook_cmp(const struct dirent **a, const struct dirent **b)
 225 {
 226         return strcmp((*a)->d_name, (*b)->d_name);
 227 }
 228
 229 static void run_boot_hooks(struct boot_task *task)
 230 {
 231         struct dirent **hooks;
 232         int i, n;
 233
 234         n = scandir(boot_hook_dir, &hooks, hook_filter, hook_cmp);
 235         if (n < 1)
 236                 return;
 237
 238         update_status(task->status_fn, task->status_arg, BOOT_STATUS_INFO,
 239                         _("running boot hooks"));
 240
 241         boot_hook_setenv(task);
 242
 243         for (i = 0; i < n; i++) {
 244                 const char *argv[2] = { NULL, NULL };
 245                 struct process *process;
 246                 char *path;
 247                 int rc;
 248
 249                 path = join_paths(task, boot_hook_dir, hooks[i]->d_name);
 250
 251                 if (access(path, X_OK)) {
 252                         talloc_free(path);
 253                         continue;
 254                 }
 255
 256                 process = process_create(task);
 257
 258                 argv[0] = path;
 259                 process->path = path;
 260                 process->argv = argv;
 261                 process->keep_stdout = true;
 262
 263                 pb_log("running boot hook %s\n", hooks[i]->d_name);
 264
 265                 rc = process_run_sync(process);
 266                 if (rc) {
 267                         pb_log("boot hook exec failed!\n");
 268
 269                 } else if (WIFEXITED(process->exit_status) &&
 270                            WEXITSTATUS(process->exit_status)
 271                                 == BOOT_HOOK_EXIT_UPDATE) {
 272                         /* if the hook returned with BOOT_HOOK_EXIT_UPDATE,
 273                          * then we process stdout to look for updated params
 274                          */
 275                         boot_hook_update(task, hooks[i]->d_name,
 276                                         process->stdout_buf);
 277                         boot_hook_setenv(task);
 278                 }
 279
 280                 process_release(process);
 281                 talloc_free(path);
 282         }
 283
 284         free(hooks);
 285 }
 286
 287 static bool load_pending(struct load_url_result *result)
 288 {
 289         return result && result->status == LOAD_ASYNC;
 290 }
 291
 292 static int check_load(struct boot_task *task, const char *name,
 293                 struct load_url_result *result)
 294 {
 295         if (!result)
 296                 return 0;
 297         if (result->status != LOAD_ERROR)
 298                 return 0;
 299
 300         update_status(task->status_fn, task->status_arg,
 301                         BOOT_STATUS_ERROR,
 302                         _("Couldn't load %s"), name);
 303         return -1;
 304 }
 305
 306 static void cleanup_load(struct load_url_result *result)
 307 {
 308         if (!result)
 309                 return;
 310         if (result->status != LOAD_OK)
 311                 return;
 312         if (!result->cleanup_local)
 313                 return;
 314         unlink(result->local);
 315 }
 316
 317 static void cleanup_cancellations(struct boot_task *task,
 318                 struct load_url_result *cur_result)
 319 {
 320         struct load_url_result *result, **results[] = {
 321                 &task->image, &task->initrd, &task->dtb,
 322         };
 323         bool pending = false;
 324         unsigned int i;
 325
 326         for (i = 0; i < ARRAY_SIZE(results); i++) {
 327                 result = *results[i];
 328
 329                 if (!result)
 330                         continue;
 331
 332                 /* We need to cleanup and free any completed loads */
 333                 if (result == cur_result || result->status == LOAD_OK
 334                                 || result->status == LOAD_ERROR) {
 335                         cleanup_load(result);
 336                         talloc_free(result);
 337                         *results[i] = NULL;
 338
 339                 /* ... and cancel any pending loads, which we'll free in
 340                  * the completion callback */
 341                 } else if (result->status == LOAD_ASYNC) {
 342                         load_url_async_cancel(result);
 343                         pending = true;
 344
 345                 /* if we're waiting for a cancellation, we still need to
 346                  * wait for the completion before freeing the boot task */
 347                 } else if (result->status == LOAD_CANCELLED) {
 348                         pending = true;
 349                 }
 350         }
 351
 352         if (!pending)
 353                 talloc_free(task);
 354 }
 355
 356 static void boot_process(struct load_url_result *result, void *data)
 357 {
 358         struct boot_task *task = data;
 359         int rc = -1;
 360
 361         if (task->cancelled) {
 362                 cleanup_cancellations(task, result);
 363                 return;
 364         }
 365
 366         if (load_pending(task->image) ||
 367                         load_pending(task->initrd) ||
 368                         load_pending(task->dtb))
 369                 return;
 370
 371         if (check_load(task, "kernel image", task->image) ||
 372                         check_load(task, "initrd", task->initrd) ||
 373                         check_load(task, "dtb", task->dtb))
 374                 goto no_load;
 375
 376         /* we make a copy of the local paths, as the boot hooks might update
 377          * and/or create these */
 378         task->local_image = task->image ? task->image->local : NULL;
 379         task->local_initrd = task->initrd ? task->initrd->local : NULL;
 380         task->local_dtb = task->dtb ? task->dtb->local : NULL;
 381
 382         run_boot_hooks(task);
 383
 384         update_status(task->status_fn, task->status_arg, BOOT_STATUS_INFO,
 385                         _("performing kexec_load"));
 386
 387         rc = kexec_load(task);
 388         if (rc) {
 389                 update_status(task->status_fn, task->status_arg,
 390                                 BOOT_STATUS_ERROR, _("kexec load failed"));
 391         }
 392
 393 no_load:
 394         cleanup_load(task->image);
 395         cleanup_load(task->initrd);
 396         cleanup_load(task->dtb);
 397
 398         if (!rc) {
 399                 update_status(task->status_fn, task->status_arg,
 400                                 BOOT_STATUS_INFO,
 401                                 _("performing kexec reboot"));
 402
 403                 rc = kexec_reboot(task);
 404                 if (rc) {
 405                         update_status(task->status_fn, task->status_arg,
 406                                         BOOT_STATUS_ERROR,
 407                                         _("kexec reboot failed"));
 408                 }
 409         }
 410 }
 411
 412 static int start_url_load(struct boot_task *task, const char *name,
 413                 struct pb_url *url, struct load_url_result **result)
 414 {
 415         if (!url)
 416                 return 0;
 417
 418         *result = load_url_async(task, url, boot_process, task);
 419         if (!*result) {
 420                 update_status(task->status_fn, task->status_arg,
 421                                 BOOT_STATUS_ERROR,
 422                                 _("Error loading %s"), name);
 423                 return -1;
 424         }
 425         return 0;
 426 }
 427
 428 struct boot_task *boot(void *ctx, struct discover_boot_option *opt,
 429                 struct boot_command *cmd, int dry_run,
 430                 boot_status_fn status_fn, void *status_arg)
 431 {
 432         struct pb_url *image = NULL, *initrd = NULL, *dtb = NULL;
 433         struct boot_task *boot_task;
 434         const char *boot_desc;
 435         int rc;
 436
 437         if (opt && opt->option->name)
 438                 boot_desc = opt->option->name;
 439         else if (cmd && cmd->boot_image_file)
 440                 boot_desc = cmd->boot_image_file;
 441         else
 442                 boot_desc = _("(unknown)");
 443
 444         update_status(status_fn, status_arg, BOOT_STATUS_INFO,
 445                         _("Booting %s."), boot_desc);
 446
 447         if (cmd && cmd->boot_image_file) {
 448                 image = pb_url_parse(opt, cmd->boot_image_file);
 449         } else if (opt && opt->boot_image) {
 450                 image = opt->boot_image->url;
 451         } else {
 452                 pb_log("%s: no image specified\n", __func__);
 453                 update_status(status_fn, status_arg, BOOT_STATUS_INFO,
 454                                 _("Boot failed: no image specified"));
 455                 return NULL;
 456         }
 457
 458         if (cmd && cmd->initrd_file) {
 459                 initrd = pb_url_parse(opt, cmd->initrd_file);
 460         } else if (opt && opt->initrd) {
 461                 initrd = opt->initrd->url;
 462         }
 463
 464         if (cmd && cmd->dtb_file) {
 465                 dtb = pb_url_parse(opt, cmd->dtb_file);
 466         } else if (opt && opt->dtb) {
 467                 dtb = opt->dtb->url;
 468         }
 469
 470         boot_task = talloc_zero(ctx, struct boot_task);
 471         boot_task->dry_run = dry_run;
 472         boot_task->status_fn = status_fn;
 473         boot_task->status_arg = status_arg;
 474
 475         if (cmd && cmd->boot_args) {
 476                 boot_task->args = talloc_strdup(boot_task, cmd->boot_args);
 477         } else if (opt && opt->option->boot_args) {
 478                 boot_task->args = talloc_strdup(boot_task,
 479                                                 opt->option->boot_args);
 480         } else {
 481                 boot_task->args = NULL;
 482         }
 483
 484         /* start async loads for boot resources */
 485         rc = start_url_load(boot_task, "kernel image", image, &boot_task->image)
 486           || start_url_load(boot_task, "initrd", initrd, &boot_task->initrd)
 487           || start_url_load(boot_task, "dtb", dtb, &boot_task->dtb);
 488
 489         /* If all URLs are local, we may be done. */
 490         if (rc) {
 491                 talloc_free(boot_task);
 492                 return NULL;
 493         }
 494
 495         boot_process(NULL, boot_task);
 496
 497         return boot_task;
 498 }
 499
 500 void boot_cancel(struct boot_task *task)
 501 {
 502         task->cancelled = true;
 503
 504         update_status(task->status_fn, task->status_arg, BOOT_STATUS_INFO,
 505                         _("Boot cancelled"));
 506
 507         cleanup_cancellations(task, NULL);
 508 }