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   1 /*
   2  * Copyright (C) 2000, 2002 Jeff Dike (jdike@karaya.com)
   3  * Licensed under the GPL
   4  */
   5
   6 #include "linux/kernel.h"
   7 #include "linux/sched.h"
   8 #include "linux/notifier.h"
   9 #include "linux/mm.h"
  10 #include "linux/types.h"
  11 #include "linux/tty.h"
  12 #include "linux/init.h"
  13 #include "linux/bootmem.h"
  14 #include "linux/spinlock.h"
  15 #include "linux/utsname.h"
  16 #include "linux/sysrq.h"
  17 #include "linux/seq_file.h"
  18 #include "linux/delay.h"
  19 #include "linux/module.h"
  20 #include "linux/utsname.h"
  21 #include "asm/page.h"
  22 #include "asm/pgtable.h"
  23 #include "asm/ptrace.h"
  24 #include "asm/elf.h"
  25 #include "asm/user.h"
  26 #include "asm/setup.h"
  27 #include "ubd_user.h"
  28 #include "asm/current.h"
  29 #include "kern_util.h"
  30 #include "as-layout.h"
  31 #include "arch.h"
  32 #include "kern.h"
  33 #include "mem_user.h"
  34 #include "mem.h"
  35 #include "initrd.h"
  36 #include "init.h"
  37 #include "os.h"
  38 #include "mode_kern.h"
  39 #include "mode.h"
  40 #include "skas.h"
  41
  42 #define DEFAULT_COMMAND_LINE "root=98:0"
  43
  44 /* Changed in add_arg and setup_arch, which run before SMP is started */
  45 static char __initdata command_line[COMMAND_LINE_SIZE] = { 0 };
  46
  47 static void __init add_arg(char *arg)
  48 {
  49         if (strlen(command_line) + strlen(arg) + 1 > COMMAND_LINE_SIZE) {
  50                 printf("add_arg: Too many command line arguments!\n");
  51                 exit(1);
  52         }
  53         if(strlen(command_line) > 0)
  54                 strcat(command_line, " ");
  55         strcat(command_line, arg);
  56 }
  57
  58 /*
  59  * These fields are initialized at boot time and not changed.
  60  * XXX This structure is used only in the non-SMP case.  Maybe this
  61  * should be moved to smp.c.
  62  */
  63 struct cpuinfo_um boot_cpu_data = {
  64         .loops_per_jiffy        = 0,
  65         .ipi_pipe               = { -1, -1 }
  66 };
  67
  68 unsigned long thread_saved_pc(struct task_struct *task)
  69 {
  70         return os_process_pc(thread_pid_skas(task));
  71 }
  72
  73 /* Changed in setup_arch, which is called in early boot */
  74 static char host_info[(__NEW_UTS_LEN + 1) * 5];
  75
  76 static int show_cpuinfo(struct seq_file *m, void *v)
  77 {
  78         int index = 0;
  79
  80 #ifdef CONFIG_SMP
  81         index = (struct cpuinfo_um *) v - cpu_data;
  82         if (!cpu_online(index))
  83                 return 0;
  84 #endif
  85
  86         seq_printf(m, "processor\t: %d\n", index);
  87         seq_printf(m, "vendor_id\t: User Mode Linux\n");
  88         seq_printf(m, "model name\t: UML\n");
  89         seq_printf(m, "mode\t\t: skas\n");
  90         seq_printf(m, "host\t\t: %s\n", host_info);
  91         seq_printf(m, "bogomips\t: %lu.%02lu\n\n",
  92                    loops_per_jiffy/(500000/HZ),
  93                    (loops_per_jiffy/(5000/HZ)) % 100);
  94
  95         return 0;
  96 }
  97
  98 static void *c_start(struct seq_file *m, loff_t *pos)
  99 {
 100         return *pos < NR_CPUS ? cpu_data + *pos : NULL;
 101 }
 102
 103 static void *c_next(struct seq_file *m, void *v, loff_t *pos)
 104 {
 105         ++*pos;
 106         return c_start(m, pos);
 107 }
 108
 109 static void c_stop(struct seq_file *m, void *v)
 110 {
 111 }
 112
 113 const struct seq_operations cpuinfo_op = {
 114         .start  = c_start,
 115         .next   = c_next,
 116         .stop   = c_stop,
 117         .show   = show_cpuinfo,
 118 };
 119
 120 /* Set in linux_main */
 121 unsigned long host_task_size;
 122 unsigned long task_size;
 123 unsigned long uml_physmem;
 124 unsigned long uml_reserved; /* Also modified in mem_init */
 125 unsigned long start_vm;
 126 unsigned long end_vm;
 127
 128 /* Set in uml_ncpus_setup */
 129 int ncpus = 1;
 130
 131 /* Set in early boot */
 132 static int have_root __initdata = 0;
 133
 134 /* Set in uml_mem_setup and modified in linux_main */
 135 long long physmem_size = 32 * 1024 * 1024;
 136
 137 static char *usage_string =
 138 "User Mode Linux v%s\n"
 139 "       available at http://user-mode-linux.sourceforge.net/\n\n";
 140
 141 static int __init uml_version_setup(char *line, int *add)
 142 {
 143         printf("%s\n", init_utsname()->release);
 144         exit(0);
 145
 146         return 0;
 147 }
 148
 149 __uml_setup("--version", uml_version_setup,
 150 "--version\n"
 151 "    Prints the version number of the kernel.\n\n"
 152 );
 153
 154 static int __init uml_root_setup(char *line, int *add)
 155 {
 156         have_root = 1;
 157         return 0;
 158 }
 159
 160 __uml_setup("root=", uml_root_setup,
 161 "root=<file containing the root fs>\n"
 162 "    This is actually used by the generic kernel in exactly the same\n"
 163 "    way as in any other kernel. If you configure a number of block\n"
 164 "    devices and want to boot off something other than ubd0, you \n"
 165 "    would use something like:\n"
 166 "        root=/dev/ubd5\n\n"
 167 );
 168
 169 static int __init no_skas_debug_setup(char *line, int *add)
 170 {
 171         printf("'debug' is not necessary to gdb UML in skas mode - run \n");
 172         printf("'gdb linux'");
 173
 174         return 0;
 175 }
 176
 177 __uml_setup("debug", no_skas_debug_setup,
 178 "debug\n"
 179 "    this flag is not needed to run gdb on UML in skas mode\n\n"
 180 );
 181
 182 #ifdef CONFIG_SMP
 183 static int __init uml_ncpus_setup(char *line, int *add)
 184 {
 185         if (!sscanf(line, "%d", &ncpus)) {
 186                 printf("Couldn't parse [%s]\n", line);
 187                 return -1;
 188         }
 189
 190         return 0;
 191 }
 192
 193 __uml_setup("ncpus=", uml_ncpus_setup,
 194 "ncpus=<# of desired CPUs>\n"
 195 "    This tells an SMP kernel how many virtual processors to start.\n\n"
 196 );
 197 #endif
 198
 199 static int __init Usage(char *line, int *add)
 200 {
 201         const char **p;
 202
 203         printf(usage_string, init_utsname()->release);
 204         p = &__uml_help_start;
 205         while (p < &__uml_help_end) {
 206                 printf("%s", *p);
 207                 p++;
 208         }
 209         exit(0);
 210         return 0;
 211 }
 212
 213 __uml_setup("--help", Usage,
 214 "--help\n"
 215 "    Prints this message.\n\n"
 216 );
 217
 218 static int __init uml_checksetup(char *line, int *add)
 219 {
 220         struct uml_param *p;
 221
 222         p = &__uml_setup_start;
 223         while(p < &__uml_setup_end) {
 224                 int n;
 225
 226                 n = strlen(p->str);
 227                 if(!strncmp(line, p->str, n)){
 228                         if (p->setup_func(line + n, add)) return 1;
 229                 }
 230                 p++;
 231         }
 232         return 0;
 233 }
 234
 235 static void __init uml_postsetup(void)
 236 {
 237         initcall_t *p;
 238
 239         p = &__uml_postsetup_start;
 240         while(p < &__uml_postsetup_end){
 241                 (*p)();
 242                 p++;
 243         }
 244         return;
 245 }
 246
 247 /* Set during early boot */
 248 unsigned long brk_start;
 249 unsigned long end_iomem;
 250 EXPORT_SYMBOL(end_iomem);
 251
 252 #define MIN_VMALLOC (32 * 1024 * 1024)
 253
 254 extern char __binary_start;
 255
 256 int __init linux_main(int argc, char **argv)
 257 {
 258         unsigned long avail, diff;
 259         unsigned long virtmem_size, max_physmem;
 260         unsigned int i, add;
 261         char * mode;
 262
 263         for (i = 1; i < argc; i++){
 264                 if((i == 1) && (argv[i][0] == ' ')) continue;
 265                 add = 1;
 266                 uml_checksetup(argv[i], &add);
 267                 if (add)
 268                         add_arg(argv[i]);
 269         }
 270         if(have_root == 0)
 271                 add_arg(DEFAULT_COMMAND_LINE);
 272
 273         os_early_checks();
 274
 275         can_do_skas();
 276
 277         if (proc_mm && ptrace_faultinfo)
 278                 mode = "SKAS3";
 279         else
 280                 mode = "SKAS0";
 281
 282         printf("UML running in %s mode\n", mode);
 283
 284         host_task_size = set_task_sizes_skas(&task_size);
 285
 286         /*
 287          * Setting up handlers to 'sig_info' struct
 288          */
 289         os_fill_handlinfo(handlinfo_kern);
 290
 291         brk_start = (unsigned long) sbrk(0);
 292         before_mem_skas(brk_start);
 293         /* Increase physical memory size for exec-shield users
 294         so they actually get what they asked for. This should
 295         add zero for non-exec shield users */
 296
 297         diff = UML_ROUND_UP(brk_start) - UML_ROUND_UP(&_end);
 298         if(diff > 1024 * 1024){
 299                 printf("Adding %ld bytes to physical memory to account for "
 300                        "exec-shield gap\n", diff);
 301                 physmem_size += UML_ROUND_UP(brk_start) - UML_ROUND_UP(&_end);
 302         }
 303
 304         uml_physmem = (unsigned long) &__binary_start & PAGE_MASK;
 305
 306         /* Reserve up to 4M after the current brk */
 307         uml_reserved = ROUND_4M(brk_start) + (1 << 22);
 308
 309         setup_machinename(init_utsname()->machine);
 310
 311         highmem = 0;
 312         iomem_size = (iomem_size + PAGE_SIZE - 1) & PAGE_MASK;
 313         max_physmem = get_kmem_end() - uml_physmem - iomem_size - MIN_VMALLOC;
 314
 315         /* Zones have to begin on a 1 << MAX_ORDER page boundary,
 316          * so this makes sure that's true for highmem
 317          */
 318         max_physmem &= ~((1 << (PAGE_SHIFT + MAX_ORDER)) - 1);
 319         if(physmem_size + iomem_size > max_physmem){
 320                 highmem = physmem_size + iomem_size - max_physmem;
 321                 physmem_size -= highmem;
 322 #ifndef CONFIG_HIGHMEM
 323                 highmem = 0;
 324                 printf("CONFIG_HIGHMEM not enabled - physical memory shrunk "
 325                        "to %Lu bytes\n", physmem_size);
 326 #endif
 327         }
 328
 329         high_physmem = uml_physmem + physmem_size;
 330         end_iomem = high_physmem + iomem_size;
 331         high_memory = (void *) end_iomem;
 332
 333         start_vm = VMALLOC_START;
 334
 335         setup_physmem(uml_physmem, uml_reserved, physmem_size, highmem);
 336         if(init_maps(physmem_size, iomem_size, highmem)){
 337                 printf("Failed to allocate mem_map for %Lu bytes of physical "
 338                        "memory and %Lu bytes of highmem\n", physmem_size,
 339                        highmem);
 340                 exit(1);
 341         }
 342
 343         virtmem_size = physmem_size;
 344         avail = get_kmem_end() - start_vm;
 345         if(physmem_size > avail) virtmem_size = avail;
 346         end_vm = start_vm + virtmem_size;
 347
 348         if(virtmem_size < physmem_size)
 349                 printf("Kernel virtual memory size shrunk to %lu bytes\n",
 350                        virtmem_size);
 351
 352         uml_postsetup();
 353
 354         stack_protections((unsigned long) &init_thread_info);
 355         os_flush_stdout();
 356
 357         return start_uml_skas();
 358 }
 359
 360 extern int uml_exitcode;
 361
 362 static int panic_exit(struct notifier_block *self, unsigned long unused1,
 363                       void *unused2)
 364 {
 365         bust_spinlocks(1);
 366         show_regs(&(current->thread.regs));
 367         bust_spinlocks(0);
 368         uml_exitcode = 1;
 369         os_dump_core();
 370         return 0;
 371 }
 372
 373 static struct notifier_block panic_exit_notifier = {
 374         .notifier_call          = panic_exit,
 375         .next                   = NULL,
 376         .priority               = 0
 377 };
 378
 379 void __init setup_arch(char **cmdline_p)
 380 {
 381         atomic_notifier_chain_register(&panic_notifier_list,
 382                         &panic_exit_notifier);
 383         paging_init();
 384         strlcpy(boot_command_line, command_line, COMMAND_LINE_SIZE);
 385         *cmdline_p = command_line;
 386         setup_hostinfo(host_info, sizeof host_info);
 387 }
 388
 389 void __init check_bugs(void)
 390 {
 391         arch_check_bugs();
 392         os_check_bugs();
 393 }
 394
 395 void apply_alternatives(struct alt_instr *start, struct alt_instr *end)
 396 {
 397 }
 398
 399 #ifdef CONFIG_SMP
 400 void alternatives_smp_module_add(struct module *mod, char *name,
 401                                  void *locks, void *locks_end,
 402                                  void *text,  void *text_end)
 403 {
 404 }
 405
 406 void alternatives_smp_module_del(struct module *mod)
 407 {
 408 }
 409 #endif