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 update_status(boot_status_fn fn, void *arg, int type,
 125                 char *message)
 126 {
 127         struct boot_status status;
 128
 129         status.type = type;
 130         status.message = message;
 131         status.progress = -1;
 132         status.detail = NULL;
 133
 134         fn(arg, &status);
 135 }
 136
 137 static void boot_hook_update_param(void *ctx, struct boot_task *task,
 138                 const char *name, const char *value)
 139 {
 140         struct p {
 141                 const char *name;
 142                 char **p;
 143         } *param, params[] = {
 144                 { "boot_image",         &task->local_image },
 145                 { "boot_initrd",        &task->local_initrd },
 146                 { "boot_dtb",           &task->local_dtb },
 147                 { "boot_args",          &task->args },
 148                 { NULL, NULL },
 149         };
 150
 151         for (param = params; param->name; param++) {
 152                 if (strcmp(param->name, name))
 153                         continue;
 154
 155                 *param->p = talloc_strdup(ctx, value);
 156                 return;
 157         }
 158 }
 159
 160 static void boot_hook_update(struct boot_task *task, const char *hookname,
 161                 char *buf)
 162 {
 163         char *line, *name, *val, *sep;
 164         char *saveptr;
 165
 166         for (;; buf = NULL) {
 167
 168                 line = strtok_r(buf, "\n", &saveptr);
 169                 if (!line)
 170                         break;
 171
 172                 sep = strchr(line, '=');
 173                 if (!sep)
 174                         continue;
 175
 176                 *sep = '\0';
 177                 name = line;
 178                 val = sep + 1;
 179
 180                 boot_hook_update_param(task, task, name, val);
 181
 182                 pb_log("boot hook %s specified %s=%s\n",
 183                                 hookname, name, val);
 184         }
 185 }
 186
 187 static void boot_hook_setenv(struct boot_task *task)
 188 {
 189         unsetenv("boot_image");
 190         unsetenv("boot_initrd");
 191         unsetenv("boot_dtb");
 192         unsetenv("boot_args");
 193
 194         setenv("boot_image", task->local_image, 1);
 195         if (task->local_initrd)
 196                 setenv("boot_initrd", task->local_initrd, 1);
 197         if (task->local_dtb)
 198                 setenv("boot_dtb", task->local_dtb, 1);
 199         if (task->args)
 200                 setenv("boot_args", task->args, 1);
 201 }
 202
 203 static int hook_filter(const struct dirent *dirent)
 204 {
 205         return dirent->d_type == DT_REG || dirent->d_type == DT_LNK;
 206 }
 207
 208 static int hook_cmp(const struct dirent **a, const struct dirent **b)
 209 {
 210         return strcmp((*a)->d_name, (*b)->d_name);
 211 }
 212
 213 static void run_boot_hooks(struct boot_task *task, boot_status_fn status_fn,
 214                 void *status_arg)
 215 {
 216         struct dirent **hooks;
 217         int i, n;
 218
 219         n = scandir(boot_hook_dir, &hooks, hook_filter, hook_cmp);
 220         if (n < 1)
 221                 return;
 222
 223         update_status(status_fn, status_arg, BOOT_STATUS_INFO,
 224                         "running boot hooks");
 225
 226         boot_hook_setenv(task);
 227
 228         for (i = 0; i < n; i++) {
 229                 const char *argv[2] = { NULL, NULL };
 230                 struct process *process;
 231                 char *path;
 232                 int rc;
 233
 234                 path = join_paths(task, boot_hook_dir, hooks[i]->d_name);
 235
 236                 if (access(path, X_OK)) {
 237                         talloc_free(path);
 238                         continue;
 239                 }
 240
 241                 process = process_create(task);
 242
 243                 argv[0] = path;
 244                 process->path = path;
 245                 process->argv = argv;
 246                 process->keep_stdout = true;
 247
 248                 pb_log("running boot hook %s\n", hooks[i]->d_name);
 249
 250                 rc = process_run_sync(process);
 251                 if (rc) {
 252                         pb_log("boot hook exec failed!\n");
 253
 254                 } else if (WIFEXITED(process->exit_status) &&
 255                            WEXITSTATUS(process->exit_status)
 256                                 == BOOT_HOOK_EXIT_UPDATE) {
 257                         /* if the hook returned with BOOT_HOOK_EXIT_UPDATE,
 258                          * then we process stdout to look for updated params
 259                          */
 260                         if (rc == BOOT_HOOK_EXIT_UPDATE) {
 261                                 boot_hook_update(task, hooks[i]->d_name,
 262                                                 process->stdout_buf);
 263                                 boot_hook_setenv(task);
 264                         }
 265                 }
 266
 267                 process_release(process);
 268                 talloc_free(path);
 269         }
 270
 271         free(hooks);
 272 }
 273
 274 int boot(void *ctx, struct discover_boot_option *opt, struct boot_command *cmd,
 275                 int dry_run, boot_status_fn status_fn, void *status_arg)
 276 {
 277         struct boot_task *boot_task;
 278         struct pb_url *image, *initrd, *dtb;
 279         unsigned int clean_image = 0;
 280         unsigned int clean_initrd = 0;
 281         unsigned int clean_dtb = 0;
 282         int result;
 283
 284         image = NULL;
 285         initrd = NULL;
 286         dtb = NULL;
 287
 288         if (cmd && cmd->boot_image_file) {
 289                 image = pb_url_parse(opt, cmd->boot_image_file);
 290         } else if (opt && opt->boot_image) {
 291                 image = opt->boot_image->url;
 292         } else {
 293                 pb_log("%s: no image specified", __func__);
 294                 return -1;
 295         }
 296
 297         boot_task = talloc_zero(ctx, struct boot_task);
 298         boot_task->dry_run = dry_run;
 299
 300         if (cmd && cmd->initrd_file) {
 301                 initrd = pb_url_parse(opt, cmd->initrd_file);
 302         } else if (opt && opt->initrd) {
 303                 initrd = opt->initrd->url;
 304         }
 305
 306         if (cmd && cmd->dtb_file) {
 307                 dtb = pb_url_parse(opt, cmd->dtb_file);
 308         } else if (opt && opt->dtb) {
 309                 dtb = opt->dtb->url;
 310         }
 311
 312         if (cmd && cmd->boot_args) {
 313                 boot_task->args = talloc_strdup(boot_task, cmd->boot_args);
 314         } else if (opt && opt->option->boot_args) {
 315                 boot_task->args = talloc_strdup(boot_task,
 316                                                 opt->option->boot_args);
 317         } else {
 318                 boot_task->args = NULL;
 319         }
 320
 321         result = -1;
 322
 323         update_status(status_fn, status_arg, BOOT_STATUS_INFO,
 324                         "loading kernel");
 325         boot_task->local_image = load_url(NULL, image, &clean_image);
 326         if (!boot_task->local_image) {
 327                 update_status(status_fn, status_arg, BOOT_STATUS_ERROR,
 328                                 "Couldn't load kernel image");
 329                 goto no_load;
 330         }
 331
 332         if (initrd) {
 333                 update_status(status_fn, status_arg, BOOT_STATUS_INFO,
 334                                 "loading initrd");
 335                 boot_task->local_initrd = load_url(NULL, initrd, &clean_initrd);
 336                 if (!boot_task->local_initrd) {
 337                         update_status(status_fn, status_arg, BOOT_STATUS_ERROR,
 338                                         "Couldn't load initrd image");
 339                         goto no_load;
 340                 }
 341         }
 342
 343         if (dtb) {
 344                 update_status(status_fn, status_arg, BOOT_STATUS_INFO,
 345                                 "loading device tree");
 346                 boot_task->local_dtb = load_url(NULL, dtb, &clean_dtb);
 347                 if (!boot_task->local_dtb) {
 348                         update_status(status_fn, status_arg, BOOT_STATUS_ERROR,
 349                                         "Couldn't load device tree");
 350                         goto no_load;
 351                 }
 352         }
 353
 354         run_boot_hooks(boot_task, status_fn, status_arg);
 355
 356         update_status(status_fn, status_arg, BOOT_STATUS_INFO,
 357                         "performing kexec_load");
 358
 359         result = kexec_load(boot_task);
 360
 361         if (result) {
 362                 update_status(status_fn, status_arg, BOOT_STATUS_ERROR,
 363                                 "kexec load failed");
 364         }
 365
 366 no_load:
 367         if (clean_image)
 368                 unlink(boot_task->local_image);
 369         if (clean_initrd)
 370                 unlink(boot_task->local_initrd);
 371         if (clean_dtb)
 372                 unlink(boot_task->local_dtb);
 373
 374         if (!result) {
 375                 update_status(status_fn, status_arg, BOOT_STATUS_INFO,
 376                                 "performing kexec reboot");
 377
 378                 result = kexec_reboot(boot_task);
 379
 380                 if (result) {
 381                         update_status(status_fn, status_arg, BOOT_STATUS_ERROR,
 382                                         "kexec reboot failed");
 383                 }
 384         }
 385
 386         talloc_free(boot_task);
 387
 388         return result;
 389 }