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