root/init/main.c

/* */

DEFINITIONS

1. get_options
2. profile_setup
3. ramdisk_start_setup
4. load_ramdisk
5. prompt_ramdisk
6. checksetup
7. calibrate_delay
8. parse_options
9. start_secondary
10. smp_idle
11. smp_init
12. smp_begin
13. start_kernel
14. printf
15. do_rc
16. do_shell
17. init

   1 /*
   2  *  linux/init/main.c
   3  *
   4  *  Copyright (C) 1991, 1992  Linus Torvalds
   5  *
   6  *  GK 2/5/95  -  Changed to support mounting root fs via NFS
   7  */
   8 
   9 #define __KERNEL_SYSCALLS__
  10 #include <stdarg.h>
  11 
  12 #include <asm/system.h>
  13 #include <asm/io.h>
  14 
  15 #include <linux/types.h>
  16 #include <linux/fcntl.h>
  17 #include <linux/config.h>
  18 #include <linux/sched.h>
  19 #include <linux/tty.h>
  20 #include <linux/head.h>
  21 #include <linux/unistd.h>
  22 #include <linux/string.h>
  23 #include <linux/timer.h>
  24 #include <linux/fs.h>
  25 #include <linux/ctype.h>
  26 #include <linux/delay.h>
  27 #include <linux/utsname.h>
  28 #include <linux/ioport.h>
  29 #include <linux/hdreg.h>
  30 #include <linux/mm.h>
  31 #include <linux/major.h>
  32 #ifdef CONFIG_APM
  33 #include <linux/apm_bios.h>
  34 #endif
  35 
  36 #include <asm/bugs.h>
  37 
  38 extern char _stext, _etext;
  39 extern char *linux_banner;
  40 
  41 static char printbuf[1024];
  42 
  43 extern int console_loglevel;
  44 
  45 static int init(void *);
  46 
  47 extern void init_IRQ(void);
  48 extern void init_modules(void);
  49 extern long console_init(long, long);
  50 extern long kmalloc_init(long,long);
  51 extern void sock_init(void);
  52 extern long pci_init(long, long);
  53 
  54 extern void swap_setup(char *str, int *ints);
  55 extern void buff_setup(char *str, int *ints);
  56 extern void bmouse_setup(char *str, int *ints);
  57 extern void eth_setup(char *str, int *ints);
  58 extern void xd_setup(char *str, int *ints);
  59 extern void floppy_setup(char *str, int *ints);
  60 extern void st_setup(char *str, int *ints);
  61 extern void st0x_setup(char *str, int *ints);
  62 extern void tmc8xx_setup(char *str, int *ints);
  63 extern void t128_setup(char *str, int *ints);
  64 extern void pas16_setup(char *str, int *ints);
  65 extern void generic_NCR5380_setup(char *str, int *intr);
  66 extern void aha152x_setup(char *str, int *ints);
  67 extern void aha1542_setup(char *str, int *ints);
  68 extern void aic7xxx_setup(char *str, int *ints);
  69 extern void BusLogic_Setup(char *str, int *ints);
  70 extern void fdomain_setup(char *str, int *ints);
  71 extern void NCR53c406a_setup(char *str, int *ints);
  72 extern void scsi_luns_setup(char *str, int *ints);
  73 extern void sound_setup(char *str, int *ints);
  74 #ifdef CONFIG_CDU31A
  75 extern void cdu31a_setup(char *str, int *ints);
  76 #endif CONFIG_CDU31A
  77 #ifdef CONFIG_MCD
  78 extern void mcd_setup(char *str, int *ints);
  79 #endif CONFIG_MCD
  80 #ifdef CONFIG_MCDX
  81 extern void mcdx_setup(char *str, int *ints);
  82 #endif CONFIG_MCDX
  83 #ifdef CONFIG_SBPCD
  84 extern void sbpcd_setup(char *str, int *ints);
  85 #endif CONFIG_SBPCD
  86 #ifdef CONFIG_AZTCD
  87 extern void aztcd_setup(char *str, int *ints);
  88 #endif CONFIG_AZTCD
  89 #ifdef CONFIG_CDU535
  90 extern void sonycd535_setup(char *str, int *ints);
  91 #endif CONFIG_CDU535
  92 #ifdef CONFIG_GSCD
  93 extern void gscd_setup(char *str, int *ints);
  94 #endif CONFIG_GSCD
  95 #ifdef CONFIG_CM206
  96 extern void cm206_setup(char *str, int *ints);
  97 #endif CONFIG_CM206
  98 #ifdef CONFIG_OPTCD
  99 extern void optcd_setup(char *str, int *ints);
 100 #endif CONFIG_OPTCD
 101 #ifdef CONFIG_SJCD
 102 extern void sjcd_setup(char *str, int *ints);
 103 #endif CONFIG_SJCD
 104 static void ramdisk_start_setup(char *str, int *ints);
 105 static void load_ramdisk(char *str, int *ints);
 106 static void prompt_ramdisk(char *str, int *ints);
 107 
 108 #ifdef CONFIG_SYSVIPC
 109 extern void ipc_init(void);
 110 #endif
 111 
 112 /*
 113  * Boot command-line arguments
 114  */
 115 #define MAX_INIT_ARGS 8
 116 #define MAX_INIT_ENVS 8
 117 
 118 extern void time_init(void);
 119 
 120 static unsigned long memory_start = 0;
 121 static unsigned long memory_end = 0;
 122 
 123 int rows, cols;
 124 
 125 extern int rd_doload;           /* 1 = load ramdisk, 0 = don't load */
 126 extern int rd_prompt;           /* 1 = prompt for ramdisk, 0 = don't prompt */
 127 extern int rd_image_start;      /* starting block # of image */
 128 int root_mountflags = MS_RDONLY;
 129 char *execute_command = 0;
 130 
 131 #ifdef CONFIG_ROOT_NFS
 132 char nfs_root_name[256] = { NFS_ROOT };
 133 char nfs_root_addrs[128] = { "" };
 134 #endif
 135 
 136 extern void dquot_init(void);
 137 
 138 static char * argv_init[MAX_INIT_ARGS+2] = { "init", NULL, };
 139 static char * envp_init[MAX_INIT_ENVS+2] = { "HOME=/", "TERM=linux", NULL, };
 140 
 141 static char * argv_rc[] = { "/bin/sh", NULL };
 142 static char * envp_rc[] = { "HOME=/", "TERM=linux", NULL };
 143 
 144 static char * argv[] = { "-/bin/sh",NULL };
 145 static char * envp[] = { "HOME=/usr/root", "TERM=linux", NULL };
 146 
 147 char *get_options(char *str, int *ints)
     /*  */
 148 {
 149         char *cur = str;
 150         int i=1;
 151 
 152         while (cur && isdigit(*cur) && i <= 10) {
 153                 ints[i++] = simple_strtoul(cur,NULL,0);
 154                 if ((cur = strchr(cur,',')) != NULL)
 155                         cur++;
 156         }
 157         ints[0] = i-1;
 158         return(cur);
 159 }
 160 
 161 static void profile_setup(char *str, int *ints)
     /*  */
 162 {
 163         if (ints[0] > 0)
 164                 prof_shift = (unsigned long) ints[1];
 165         else
 166 #ifdef CONFIG_PROFILE_SHIFT
 167                 prof_shift = CONFIG_PROFILE_SHIFT;
 168 #else
 169                 prof_shift = 2;
 170 #endif
 171 }
 172 
 173 struct {
 174         const char *str;
 175         void (*setup_func)(char *, int *);
 176 } bootsetups[] = {
 177         { "reserve=", reserve_setup },
 178         { "profile=", profile_setup },
 179         { "ramdisk_start=", ramdisk_start_setup },
 180         { "load_ramdisk", load_ramdisk },
 181         { "prompt_ramdisk", prompt_ramdisk },
 182         { "swap=", swap_setup },
 183         { "buff=", buff_setup },
 184 #ifdef CONFIG_BUGi386
 185         { "no-hlt", no_halt },
 186         { "no387", no_387 },
 187 #endif
 188 #ifdef CONFIG_INET
 189         { "ether=", eth_setup },
 190 #endif
 191 #ifdef CONFIG_SCSI
 192         { "max_scsi_luns=", scsi_luns_setup },
 193 #endif
 194 #if defined(CONFIG_BLK_DEV_HD)
 195         { "hd=", hd_setup },
 196 #endif
 197 #ifdef CONFIG_CHR_DEV_ST
 198         { "st=", st_setup },
 199 #endif
 200 #ifdef CONFIG_BUSMOUSE
 201         { "bmouse=", bmouse_setup },
 202 #endif
 203 #ifdef CONFIG_SCSI_SEAGATE
 204         { "st0x=", st0x_setup },
 205         { "tmc8xx=", tmc8xx_setup },
 206 #endif
 207 #ifdef CONFIG_SCSI_T128
 208         { "t128=", t128_setup },
 209 #endif
 210 #ifdef CONFIG_SCSI_PAS16
 211         { "pas16=", pas16_setup },
 212 #endif
 213 #ifdef CONFIG_SCSI_GENERIC_NCR5380
 214         { "ncr5380=", generic_NCR5380_setup },
 215 #endif
 216 #ifdef CONFIG_SCSI_AHA152X
 217         { "aha152x=", aha152x_setup},
 218 #endif
 219 #ifdef CONFIG_SCSI_AHA1542
 220         { "aha1542=", aha1542_setup},
 221 #endif
 222 #ifdef CONFIG_SCSI_AIC7XXX
 223         { "aic7xxx=", aic7xxx_setup},
 224 #endif
 225 #ifdef CONFIG_SCSI_BUSLOGIC
 226         { "BusLogic=", BusLogic_Setup},
 227 #endif
 228 #ifdef CONFIG_SCSI_NCR53C406A
 229         { "ncr53c406a=", NCR53c406a_setup},
 230 #endif
 231 #ifdef CONFIG_SCSI_FUTURE_DOMAIN
 232         { "fdomain=", fdomain_setup},
 233 #endif
 234 #ifdef CONFIG_BLK_DEV_XD
 235         { "xd=", xd_setup },
 236 #endif
 237 #ifdef CONFIG_BLK_DEV_FD
 238         { "floppy=", floppy_setup },
 239 #endif
 240 #ifdef CONFIG_CDU31A
 241         { "cdu31a=", cdu31a_setup },
 242 #endif CONFIG_CDU31A
 243 #ifdef CONFIG_MCD
 244         { "mcd=", mcd_setup },
 245 #endif CONFIG_MCD
 246 #ifdef CONFIG_MCDX
 247         { "mcdx=", mcdx_setup },
 248 #endif CONFIG_MCDX
 249 #ifdef CONFIG_SBPCD
 250         { "sbpcd=", sbpcd_setup },
 251 #endif CONFIG_SBPCD
 252 #ifdef CONFIG_AZTCD
 253         { "aztcd=", aztcd_setup },
 254 #endif CONFIG_AZTCD
 255 #ifdef CONFIG_CDU535
 256         { "sonycd535=", sonycd535_setup },
 257 #endif CONFIG_CDU535
 258 #ifdef CONFIG_GSCD
 259         { "gscd=", gscd_setup },
 260 #endif CONFIG_GSCD
 261 #ifdef CONFIG_CM206
 262         { "cm206=", cm206_setup },
 263 #endif CONFIG_CM206
 264 #ifdef CONFIG_OPTCD
 265         { "optcd=", optcd_setup },
 266 #endif CONFIG_OPTCD
 267 #ifdef CONFIG_SJCD
 268         { "sjcd=", sjcd_setup },
 269 #endif CONFIG_SJCD
 270 #ifdef CONFIG_SOUND
 271         { "sound=", sound_setup },
 272 #endif
 273         { 0, 0 }
 274 };
 275 
 276 static void ramdisk_start_setup(char *str, int *ints)
     /*  */
 277 {
 278    if (ints[0] > 0 && ints[1] >= 0)
 279       rd_image_start = ints[1];
 280 }
 281 
 282 static void load_ramdisk(char *str, int *ints)
     /*  */
 283 {
 284         rd_doload = 1;
 285 }
 286 
 287 static void prompt_ramdisk(char *str, int *ints)
     /*  */
 288 {
 289         rd_prompt = 1;
 290 }
 291 
 292 static int checksetup(char *line)
     /*  */
 293 {
 294         int i = 0;
 295         int ints[11];
 296 
 297 #ifdef CONFIG_BLK_DEV_IDE
 298         /* ide driver needs the basic string, rather than pre-processed values */
 299         if (!strncmp(line,"ide",3) || (!strncmp(line,"hd",2) && line[2] != '=')) {
 300                 ide_setup(line);
 301                 return 1;
 302         }
 303 #endif
 304         while (bootsetups[i].str) {
 305                 int n = strlen(bootsetups[i].str);
 306                 if (!strncmp(line,bootsetups[i].str,n)) {
 307                         bootsetups[i].setup_func(get_options(line+n,ints), ints);
 308                         return 1;
 309                 }
 310                 i++;
 311         }
 312         return 0;
 313 }
 314 
 315 /* this should be approx 2 Bo*oMips to start (note initial shift), and will
 316    still work even if initally too large, it will just take slightly longer */
 317 unsigned long loops_per_sec = (1<<12);
 318 
 319 /* This is the number of bits of precision for the loops_per_second.  Each
 320    bit takes on average 1.5/HZ seconds.  This (like the original) is a little
 321    better than 1% */
 322 #define LPS_PREC 8
 323 
 324 void calibrate_delay(void)
     /*  */
 325 {
 326         int ticks;
 327         int loopbit;
 328         int lps_precision = LPS_PREC;
 329 
 330         loops_per_sec = (1<<12);
 331 
 332         printk("Calibrating delay loop.. ");
 333         while (loops_per_sec <<= 1) {
 334                 /* wait for "start of" clock tick */
 335                 ticks = jiffies;
 336                 while (ticks == jiffies)
 337                         /* nothing */;
 338                 /* Go .. */
 339                 ticks = jiffies;
 340                 __delay(loops_per_sec);
 341                 ticks = jiffies - ticks;
 342                 if (ticks)
 343                         break;
 344                 }
 345 
 346 /* Do a binary approximation to get loops_per_second set to equal one clock
 347    (up to lps_precision bits) */
 348         loops_per_sec >>= 1;
 349         loopbit = loops_per_sec;
 350         while ( lps_precision-- && (loopbit >>= 1) ) {
 351                 loops_per_sec |= loopbit;
 352                 ticks = jiffies;
 353                 while (ticks == jiffies);
 354                 ticks = jiffies;
 355                 __delay(loops_per_sec);
 356                 if (jiffies != ticks)   /* longer than 1 tick */
 357                         loops_per_sec &= ~loopbit;
 358         }
 359 
 360 /* finally, adjust loops per second in terms of seconds instead of clocks */    
 361         loops_per_sec *= HZ;
 362 /* Round the value and print it */      
 363         printk("ok - %lu.%02lu BogoMIPS\n",
 364                 (loops_per_sec+2500)/500000,
 365                 ((loops_per_sec+2500)/5000) % 100);
 366 }
 367 
 368 /*
 369  * This is a simple kernel command line parsing function: it parses
 370  * the command line, and fills in the arguments/environment to init
 371  * as appropriate. Any cmd-line option is taken to be an environment
 372  * variable if it contains the character '='.
 373  *
 374  *
 375  * This routine also checks for options meant for the kernel.
 376  * These options are not given to init - they are for internal kernel use only.
 377  */
 378 static void parse_options(char *line)
     /*  */
 379 {
 380         char *next;
 381 #ifdef CONFIG_ROOT_NFS
 382         char *devnames[] = { "nfs", "hda", "hdb", "hdc", "hdd", "sda", "sdb", "sdc", "sdd", "sde", "fd", "xda", "xdb", NULL };
 383         int devnums[]    = { 0x0FF, 0x300, 0x340, 0x1600, 0x1640, 0x800, 0x810, 0x820, 0x830, 0x840, 0x200, 0xD00, 0xD40, 0};
 384 #else
 385         static const char *devnames[] = { "hda", "hdb", "hdc", "hdd", "sda", "sdb", "sdc", "sdd", "sde", "fd", "xda", "xdb", NULL };
 386         static int devnums[]    = { 0x300, 0x340, 0x1600, 0x1640, 0x800, 0x810, 0x820, 0x830, 0x840, 0x200, 0xD00, 0xD40, 0};
 387 #endif
 388         int args, envs;
 389         if (!*line)
 390                 return;
 391         args = 0;
 392         envs = 1;       /* TERM is set to 'linux' by default */
 393         next = line;
 394         while ((line = next) != NULL) {
 395                 if ((next = strchr(line,' ')) != NULL)
 396                         *next++ = 0;
 397                 /*
 398                  * check for kernel options first..
 399                  */
 400                 if (!strncmp(line,"root=",5)) {
 401                         int n;
 402                         line += 5;
 403                         if (strncmp(line,"/dev/",5)) {
 404                                 ROOT_DEV = to_kdev_t(
 405                                              simple_strtoul(line,NULL,16));
 406                                 continue;
 407                         }
 408                         line += 5;
 409                         for (n = 0 ; devnames[n] ; n++) {
 410                                 int len = strlen(devnames[n]);
 411                                 if (!strncmp(line,devnames[n],len)) {
 412                                         ROOT_DEV = to_kdev_t(devnums[n]+
 413                                              simple_strtoul(line+len,NULL,0));
 414                                         break;
 415                                 }
 416                         }
 417                         continue;
 418                 }
 419 #ifdef CONFIG_ROOT_NFS
 420                 if (!strncmp(line, "nfsroot=", 8)) {
 421                         int n;
 422                         line += 8;
 423                         ROOT_DEV = MKDEV(UNNAMED_MAJOR, 255);
 424                         if (line[0] == '/' || (line[0] >= '0' && line[0] <= '9')) {
 425                                 strncpy(nfs_root_name, line, sizeof(nfs_root_name));
 426                                 nfs_root_name[sizeof(nfs_root_name)] = '\0';
 427                                 continue;
 428                         }
 429                         n = strlen(line) + strlen(NFS_ROOT);
 430                         if (n >= sizeof(nfs_root_name))
 431                                 line[sizeof(nfs_root_name) - strlen(NFS_ROOT) - 1] = '\0';
 432                         sprintf(nfs_root_name, NFS_ROOT, line);
 433                         continue;
 434                 }
 435                 if (!strncmp(line, "nfsaddrs=", 9)) {
 436                         line += 9;
 437                         strncpy(nfs_root_addrs, line, sizeof(nfs_root_addrs));
 438                         nfs_root_addrs[sizeof(nfs_root_addrs)] = '\0';
 439                         continue;
 440                 }
 441 #endif
 442                 if (!strcmp(line,"ro")) {
 443                         root_mountflags |= MS_RDONLY;
 444                         continue;
 445                 }
 446                 if (!strcmp(line,"rw")) {
 447                         root_mountflags &= ~MS_RDONLY;
 448                         continue;
 449                 }
 450                 if (!strcmp(line,"debug")) {
 451                         console_loglevel = 10;
 452                         continue;
 453                 }
 454                 if (!strncmp(line,"init=",5)) {
 455                         line += 5;
 456                         execute_command = line;
 457                         continue;
 458                 }
 459                 if (checksetup(line))
 460                         continue;
 461                 /*
 462                  * Then check if it's an environment variable or
 463                  * an option.
 464                  */
 465                 if (strchr(line,'=')) {
 466                         if (envs >= MAX_INIT_ENVS)
 467                                 break;
 468                         envp_init[++envs] = line;
 469                 } else {
 470                         if (args >= MAX_INIT_ARGS)
 471                                 break;
 472                         argv_init[++args] = line;
 473                 }
 474         }
 475         argv_init[args+1] = NULL;
 476         envp_init[envs+1] = NULL;
 477 }
 478 
 479 extern void setup_arch(char **, unsigned long *, unsigned long *);
 480 
 481 #ifdef __SMP__
 482 /*
 483  *      Activate a secondary processor.
 484  */
 485  
 486 asmlinkage void start_secondary(void)
     /*  */
 487 {
 488         trap_init();
 489         init_IRQ();
 490         smp_callin();
 491         for(;;)
 492                 idle();
 493 }
 494 
 495 int smp_idle(void * unused)
     /*  */
 496 {
 497         for (;;)
 498                 idle();
 499 }
 500 
 501 /*
 502  *      Called by CPU#0 to activate the rest.
 503  */
 504  
 505 static void smp_init(void)
     /*  */
 506 {
 507         int i=0;
 508         smp_boot_cpus();
 509         
 510         /*
 511          *      Create the slave init tasks as sharing pid 0.
 512          */
 513 
 514         for(i=1;i<smp_num_cpus;i++)
 515         {
 516                 kernel_thread(smp_idle, NULL, CLONE_PID);
 517                 /*
 518                  *      Assume linear processor numbering
 519                  */
 520                 current_set[i]=task[i];
 521                 current_set[i]->processor=i;
 522         }
 523 }               
 524 
 525 /*
 526  *      The autoprobe routines assume CPU#0 on the i386
 527  *      so we don't actually set the game in motion until
 528  *      they are finished.
 529  */
 530  
 531 static void smp_begin(void)
     /*  */
 532 {
 533         smp_threads_ready=1;
 534         smp_commence();
 535 }
 536         
 537 #endif
 538 
 539 /*
 540  *      Activate the first processor.
 541  */
 542  
 543 asmlinkage void start_kernel(void)
     /*  */
 544 {
 545         char * command_line;
 546 
 547 /*
 548  *      This little check will move.
 549  */
 550 
 551 #ifdef __SMP__
 552         static int first_cpu=1;
 553         
 554         if(!first_cpu)
 555                 start_secondary();
 556         first_cpu=0;
 557         
 558 #endif  
 559 /*
 560  * Interrupts are still disabled. Do necessary setups, then
 561  * enable them
 562  */
 563         setup_arch(&command_line, &memory_start, &memory_end);
 564         memory_start = paging_init(memory_start,memory_end);
 565         trap_init();
 566         init_IRQ();
 567         sched_init();
 568         time_init();
 569         parse_options(command_line);
 570         init_modules();
 571 #ifdef CONFIG_PROFILE
 572         if (!prof_shift)
 573 #ifdef CONFIG_PROFILE_SHIFT
 574                 prof_shift = CONFIG_PROFILE_SHIFT;
 575 #else
 576                 prof_shift = 2;
 577 #endif
 578 #endif
 579         if (prof_shift) {
 580                 prof_buffer = (unsigned long *) memory_start;
 581                 /* only text is profiled */
 582                 prof_len = (unsigned long) &_etext - (unsigned long) &_stext;
 583                 prof_len >>= prof_shift;
 584                 memory_start += prof_len * sizeof(unsigned long);
 585         }
 586         memory_start = console_init(memory_start,memory_end);
 587 #ifdef CONFIG_PCI
 588         memory_start = pci_init(memory_start,memory_end);
 589 #endif
 590         memory_start = kmalloc_init(memory_start,memory_end);
 591         sti();
 592         calibrate_delay();
 593         memory_start = inode_init(memory_start,memory_end);
 594         memory_start = file_table_init(memory_start,memory_end);
 595         memory_start = name_cache_init(memory_start,memory_end);
 596         mem_init(memory_start,memory_end);
 597         buffer_init();
 598         sock_init();
 599 #ifdef CONFIG_SYSVIPC
 600         ipc_init();
 601 #endif
 602 #ifdef CONFIG_APM
 603         apm_bios_init();
 604 #endif
 605         dquot_init();
 606         sti();
 607         check_bugs();
 608 
 609         printk(linux_banner);
 610 #ifdef __SMP__
 611         smp_init();
 612 #endif
 613         /* we count on the initial thread going ok */
 614         kernel_thread(init, NULL, 0);
 615 /*
 616  * task[0] is meant to be used as an "idle" task: it may not sleep, but
 617  * it might do some general things like count free pages or it could be
 618  * used to implement a reasonable LRU algorithm for the paging routines:
 619  * anything that can be useful, but shouldn't take time from the real
 620  * processes.
 621  *
 622  * Right now task[0] just does a infinite idle loop.
 623  */
 624         for(;;)
 625                 idle();
 626 }
 627 
 628 static int printf(const char *fmt, ...)
     /*  */
 629 {
 630         va_list args;
 631         int i;
 632 
 633         va_start(args, fmt);
 634         write(1,printbuf,i=vsprintf(printbuf, fmt, args));
 635         va_end(args);
 636         return i;
 637 }
 638 
 639 static int do_rc(void * rc)
     /*  */
 640 {
 641         close(0);
 642         if (open(rc,O_RDONLY,0))
 643                 return -1;
 644         return execve("/bin/sh", argv_rc, envp_rc);
 645 }
 646 
 647 static int do_shell(void * shell)
     /*  */
 648 {
 649         close(0);close(1);close(2);
 650         setsid();
 651         (void) open("/dev/tty1",O_RDWR,0);
 652         (void) dup(0);
 653         (void) dup(0);
 654         return execve(shell, argv, envp);
 655 }
 656 
 657 static int init(void * unused)
     /*  */
 658 {
 659         int pid,i;
 660 
 661         setup();
 662 
 663 #ifdef __SMP__
 664         /*
 665          *      With the devices probed and setup we can
 666          *      now enter SMP mode.
 667          */
 668         
 669         smp_begin();
 670 #endif  
 671 
 672         #ifdef CONFIG_UMSDOS_FS
 673         {
 674                 /*
 675                         When mounting a umsdos fs as root, we detect
 676                         the pseudo_root (/linux) and initialise it here.
 677                         pseudo_root is defined in fs/umsdos/inode.c
 678                 */
 679                 extern struct inode *pseudo_root;
 680                 if (pseudo_root != NULL){
 681                         current->fs->root = pseudo_root;
 682                         current->fs->pwd  = pseudo_root;
 683                 }
 684         }
 685         #endif
 686 
 687         (void) open("/dev/tty1",O_RDWR,0);
 688         (void) dup(0);
 689         (void) dup(0);
 690 
 691         if (!execute_command) {
 692                 execve("/etc/init",argv_init,envp_init);
 693                 execve("/bin/init",argv_init,envp_init);
 694                 execve("/sbin/init",argv_init,envp_init);
 695                 /* if this fails, fall through to original stuff */
 696 
 697                 pid = kernel_thread(do_rc, "/etc/rc", SIGCHLD);
 698                 if (pid>0)
 699                         while (pid != wait(&i))
 700                                 /* nothing */;
 701                 }
 702 
 703         while (1) {
 704                 pid = kernel_thread(do_shell,
 705                         execute_command ? execute_command : "/bin/sh",
 706                         SIGCHLD);
 707                 if (pid < 0) {
 708                         printf("Fork failed in init\n\r");
 709                         continue;
 710                 }
 711                 while (1)
 712                         if (pid == wait(&i))
 713                                 break;
 714                 printf("\n\rchild %d died with code %04x\n\r",pid,i);
 715                 sync();
 716         }
 717         return -1;
 718 }

/* */