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

   1
   2 #define _GNU_SOURCE
   3
   4 #include <stdbool.h>
   5 #include <stdlib.h>
   6 #include <assert.h>
   7 #include <dirent.h>
   8 #include <string.h>
   9 #include <fcntl.h>
  10 #include <sys/types.h>
  11
  12 #include <log/log.h>
  13 #include <pb-protocol/pb-protocol.h>
  14 #include <process/process.h>
  15 #include <system/system.h>
  16 #include <talloc/talloc.h>
  17 #include <url/url.h>
  18
  19 #include "device-handler.h"
  20 #include "boot.h"
  21 #include "paths.h"
  22 #include "resource.h"
  23
  24 static const char *boot_hook_dir = PKG_SYSCONF_DIR "/boot.d";
  25 enum {
  26         BOOT_HOOK_EXIT_OK       = 0,
  27         BOOT_HOOK_EXIT_UPDATE   = 2,
  28 };
  29
  30
  31 struct boot_task {
  32         char *local_image;
  33         char *local_initrd;
  34         char *local_dtb;
  35         char *args;
  36
  37         bool dry_run;
  38 };
  39
  40 /**
  41  * kexec_load - kexec load helper.
  42  */
  43 static int kexec_load(struct boot_task *boot_task)
  44 {
  45         int result;
  46         const char *argv[7];
  47         const char **p;
  48         char *s_initrd = NULL;
  49         char *s_dtb = NULL;
  50         char *s_args = NULL;
  51
  52         p = argv;
  53         *p++ = pb_system_apps.kexec;    /* 1 */
  54         *p++ = "-l";                    /* 2 */
  55
  56         if (boot_task->local_initrd) {
  57                 s_initrd = talloc_asprintf(boot_task, "--initrd=%s",
  58                                 boot_task->local_initrd);
  59                 assert(s_initrd);
  60                 *p++ = s_initrd;         /* 3 */
  61         }
  62
  63         if (boot_task->local_dtb) {
  64                 s_dtb = talloc_asprintf(boot_task, "--dtb=%s",
  65                                                 boot_task->local_dtb);
  66                 assert(s_dtb);
  67                 *p++ = s_dtb;            /* 4 */
  68         }
  69
  70         if (boot_task->args) {
  71                 s_args = talloc_asprintf(boot_task, "--append=%s",
  72                                                 boot_task->args);
  73                 assert(s_args);
  74                 *p++ = s_args;          /* 5 */
  75         }
  76
  77         *p++ = boot_task->local_image;  /* 6 */
  78         *p++ = NULL;                    /* 7 */
  79
  80         result = process_run_simple_argv(boot_task, argv);
  81
  82         if (result)
  83                 pb_log("%s: failed: (%d)\n", __func__, result);
  84
  85         return result;
  86 }
  87
  88 /**
  89  * kexec_reboot - Helper to boot the new kernel.
  90  *
  91  * Must only be called after a successful call to kexec_load().
  92  */
  93
  94 static int kexec_reboot(struct boot_task *task)
  95 {
  96         int result;
  97
  98         /* First try running shutdown.  Init scripts should run 'exec -e' */
  99         result = process_run_simple(task, pb_system_apps.shutdown, "-r",
 100                         "now", NULL);
 101
 102         /* On error, force a kexec with the -e option */
 103         if (result) {
 104                 result = process_run_simple(task, pb_system_apps.kexec,
 105                                                 "-e", NULL);
 106         }
 107
 108         if (result)
 109                 pb_log("%s: failed: (%d)\n", __func__, result);
 110
 111         /* okay, kexec -e -f */
 112         if (result) {
 113                 result = process_run_simple(task, pb_system_apps.kexec,
 114                                                 "-e", "-f", NULL);
 115         }
 116
 117         if (result)
 118                 pb_log("%s: failed: (%d)\n", __func__, result);
 119
 120
 121         return result;
 122 }
 123
 124 static void __attribute__((format(__printf__, 4, 5))) update_status(
 125                 boot_status_fn fn, void *arg, int type, char *fmt, ...)
 126 {
 127         struct boot_status status;
 128         va_list ap;
 129
 130         va_start(ap, fmt);
 131         status.message = talloc_vasprintf(NULL, fmt, ap);
 132         va_end(ap);
 133
 134         status.type = type;
 135         status.progress = -1;
 136         status.detail = NULL;
 137
 138         fn(arg, &status);
 139
 140         talloc_free(status.message);
 141 }
 142
 143 static void boot_hook_update_param(void *ctx, struct boot_task *task,
 144                 const char *name, const char *value)
 145 {
 146         struct p {
 147                 const char *name;
 148                 char **p;
 149         } *param, params[] = {
 150                 { "boot_image",         &task->local_image },
 151                 { "boot_initrd",        &task->local_initrd },
 152                 { "boot_dtb",           &task->local_dtb },
 153                 { "boot_args",          &task->args },
 154                 { NULL, NULL },
 155         };
 156
 157         for (param = params; param->name; param++) {
 158                 if (strcmp(param->name, name))
 159                         continue;
 160
 161                 *param->p = talloc_strdup(ctx, value);
 162                 return;
 163         }
 164 }
 165
 166 static void boot_hook_update(struct boot_task *task, const char *hookname,
 167                 char *buf)
 168 {
 169         char *line, *name, *val, *sep;
 170         char *saveptr;
 171
 172         for (;; buf = NULL) {
 173
 174                 line = strtok_r(buf, "\n", &saveptr);
 175                 if (!line)
 176                         break;
 177
 178                 sep = strchr(line, '=');
 179                 if (!sep)
 180                         continue;
 181
 182                 *sep = '\0';
 183                 name = line;
 184                 val = sep + 1;
 185
 186                 boot_hook_update_param(task, task, name, val);
 187
 188                 pb_log("boot hook %s specified %s=%s\n",
 189                                 hookname, name, val);
 190         }
 191 }
 192
 193 static void boot_hook_setenv(struct boot_task *task)
 194 {
 195         unsetenv("boot_image");
 196         unsetenv("boot_initrd");
 197         unsetenv("boot_dtb");
 198         unsetenv("boot_args");
 199
 200         setenv("boot_image", task->local_image, 1);
 201         if (task->local_initrd)
 202                 setenv("boot_initrd", task->local_initrd, 1);
 203         if (task->local_dtb)
 204                 setenv("boot_dtb", task->local_dtb, 1);
 205         if (task->args)
 206                 setenv("boot_args", task->args, 1);
 207 }
 208
 209 static int hook_filter(const struct dirent *dirent)
 210 {
 211         return dirent->d_type == DT_REG || dirent->d_type == DT_LNK;
 212 }
 213
 214 static int hook_cmp(const struct dirent **a, const struct dirent **b)
 215 {
 216         return strcmp((*a)->d_name, (*b)->d_name);
 217 }
 218
 219 static void run_boot_hooks(struct boot_task *task, boot_status_fn status_fn,
 220                 void *status_arg)
 221 {
 222         struct dirent **hooks;
 223         int i, n;
 224
 225         n = scandir(boot_hook_dir, &hooks, hook_filter, hook_cmp);
 226         if (n < 1)
 227                 return;
 228
 229         update_status(status_fn, status_arg, BOOT_STATUS_INFO,
 230                         "running boot hooks");
 231
 232         boot_hook_setenv(task);
 233
 234         for (i = 0; i < n; i++) {
 235                 const char *argv[2] = { NULL, NULL };
 236                 struct process *process;
 237                 char *path;
 238                 int rc;
 239
 240                 path = join_paths(task, boot_hook_dir, hooks[i]->d_name);
 241
 242                 if (access(path, X_OK)) {
 243                         talloc_free(path);
 244                         continue;
 245                 }
 246
 247                 process = process_create(task);
 248
 249                 argv[0] = path;
 250                 process->path = path;
 251                 process->argv = argv;
 252                 process->keep_stdout = true;
 253
 254                 pb_log("running boot hook %s\n", hooks[i]->d_name);
 255
 256                 rc = process_run_sync(process);
 257                 if (rc) {
 258                         pb_log("boot hook exec failed!\n");
 259
 260                 } else if (WIFEXITED(process->exit_status) &&
 261                            WEXITSTATUS(process->exit_status)
 262                                 == BOOT_HOOK_EXIT_UPDATE) {
 263                         /* if the hook returned with BOOT_HOOK_EXIT_UPDATE,
 264                          * then we process stdout to look for updated params
 265                          */
 266                         if (rc == BOOT_HOOK_EXIT_UPDATE) {
 267                                 boot_hook_update(task, hooks[i]->d_name,
 268                                                 process->stdout_buf);
 269                                 boot_hook_setenv(task);
 270                         }
 271                 }
 272
 273                 process_release(process);
 274                 talloc_free(path);
 275         }
 276
 277         free(hooks);
 278 }
 279
 280 int boot(void *ctx, struct discover_boot_option *opt, struct boot_command *cmd,
 281                 int dry_run, boot_status_fn status_fn, void *status_arg)
 282 {
 283         struct boot_task *boot_task;
 284         struct pb_url *image, *initrd, *dtb;
 285         unsigned int clean_image = 0;
 286         unsigned int clean_initrd = 0;
 287         unsigned int clean_dtb = 0;
 288         const char *boot_desc;
 289         int result;
 290
 291         image = NULL;
 292         initrd = NULL;
 293         dtb = NULL;
 294
 295         if (opt && opt->option->name)
 296                 boot_desc = opt->option->name;
 297         else if (cmd && cmd->boot_image_file)
 298                 boot_desc = cmd->boot_image_file;
 299         else
 300                 boot_desc = "(unknown)";
 301
 302         update_status(status_fn, status_arg, BOOT_STATUS_INFO,
 303                         "Booting %s.", boot_desc);
 304
 305         if (cmd && cmd->boot_image_file) {
 306                 image = pb_url_parse(opt, cmd->boot_image_file);
 307         } else if (opt && opt->boot_image) {
 308                 image = opt->boot_image->url;
 309         } else {
 310                 pb_log("%s: no image specified\n", __func__);
 311                 update_status(status_fn, status_arg, BOOT_STATUS_INFO,
 312                                 "Boot failed: no image specified");
 313                 return -1;
 314         }
 315
 316         boot_task = talloc_zero(ctx, struct boot_task);
 317         boot_task->dry_run = dry_run;
 318
 319         if (cmd && cmd->initrd_file) {
 320                 initrd = pb_url_parse(opt, cmd->initrd_file);
 321         } else if (opt && opt->initrd) {
 322                 initrd = opt->initrd->url;
 323         }
 324
 325         if (cmd && cmd->dtb_file) {
 326                 dtb = pb_url_parse(opt, cmd->dtb_file);
 327         } else if (opt && opt->dtb) {
 328                 dtb = opt->dtb->url;
 329         }
 330
 331         if (cmd && cmd->boot_args) {
 332                 boot_task->args = talloc_strdup(boot_task, cmd->boot_args);
 333         } else if (opt && opt->option->boot_args) {
 334                 boot_task->args = talloc_strdup(boot_task,
 335                                                 opt->option->boot_args);
 336         } else {
 337                 boot_task->args = NULL;
 338         }
 339
 340         result = -1;
 341
 342         update_status(status_fn, status_arg, BOOT_STATUS_INFO,
 343                         "loading kernel");
 344         boot_task->local_image = load_url(NULL, image, &clean_image);
 345         if (!boot_task->local_image) {
 346                 update_status(status_fn, status_arg, BOOT_STATUS_ERROR,
 347                                 "Couldn't load kernel image");
 348                 goto no_load;
 349         }
 350
 351         if (initrd) {
 352                 update_status(status_fn, status_arg, BOOT_STATUS_INFO,
 353                                 "loading initrd");
 354                 boot_task->local_initrd = load_url(NULL, initrd, &clean_initrd);
 355                 if (!boot_task->local_initrd) {
 356                         update_status(status_fn, status_arg, BOOT_STATUS_ERROR,
 357                                         "Couldn't load initrd image");
 358                         goto no_load;
 359                 }
 360         }
 361
 362         if (dtb) {
 363                 update_status(status_fn, status_arg, BOOT_STATUS_INFO,
 364                                 "loading device tree");
 365                 boot_task->local_dtb = load_url(NULL, dtb, &clean_dtb);
 366                 if (!boot_task->local_dtb) {
 367                         update_status(status_fn, status_arg, BOOT_STATUS_ERROR,
 368                                         "Couldn't load device tree");
 369                         goto no_load;
 370                 }
 371         }
 372
 373         run_boot_hooks(boot_task, status_fn, status_arg);
 374
 375         update_status(status_fn, status_arg, BOOT_STATUS_INFO,
 376                         "performing kexec_load");
 377
 378         result = kexec_load(boot_task);
 379
 380         if (result) {
 381                 update_status(status_fn, status_arg, BOOT_STATUS_ERROR,
 382                                 "kexec load failed");
 383         }
 384
 385 no_load:
 386         if (clean_image)
 387                 unlink(boot_task->local_image);
 388         if (clean_initrd)
 389                 unlink(boot_task->local_initrd);
 390         if (clean_dtb)
 391                 unlink(boot_task->local_dtb);
 392
 393         if (!result) {
 394                 update_status(status_fn, status_arg, BOOT_STATUS_INFO,
 395                                 "performing kexec reboot");
 396
 397                 result = kexec_reboot(boot_task);
 398
 399                 if (result) {
 400                         update_status(status_fn, status_arg, BOOT_STATUS_ERROR,
 401                                         "kexec reboot failed");
 402                 }
 403         }
 404
 405         talloc_free(boot_task);
 406
 407         return result;
 408 }