1 /* 2 * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com) 3 * Licensed under the GPL 4 */ 5 6 #include <linux/delay.h> 7 #include <linux/init.h> 8 #include <linux/mm.h> 9 #include <linux/module.h> 10 #include <linux/seq_file.h> 11 #include <linux/string.h> 12 #include <linux/utsname.h> 13 #include <linux/sched.h> 14 #include <asm/pgtable.h> 15 #include <asm/processor.h> 16 #include <asm/sections.h> 17 #include <asm/setup.h> 18 #include <as-layout.h> 19 #include <arch.h> 20 #include <init.h> 21 #include <kern.h> 22 #include <kern_util.h> 23 #include <mem_user.h> 24 #include <os.h> 25 26 #define DEFAULT_COMMAND_LINE "root=98:0" 27 28 /* Changed in add_arg and setup_arch, which run before SMP is started */ 29 static char __initdata command_line[COMMAND_LINE_SIZE] = { 0 }; 30 31 static void __init add_arg(char *arg) 32 { 33 if (strlen(command_line) + strlen(arg) + 1 > COMMAND_LINE_SIZE) { 34 printf("add_arg: Too many command line arguments!\n"); 35 exit(1); 36 } 37 if (strlen(command_line) > 0) 38 strcat(command_line, " "); 39 strcat(command_line, arg); 40 } 41 42 /* 43 * These fields are initialized at boot time and not changed. 44 * XXX This structure is used only in the non-SMP case. Maybe this 45 * should be moved to smp.c. 46 */ 47 struct cpuinfo_um boot_cpu_data = { 48 .loops_per_jiffy = 0, 49 .ipi_pipe = { -1, -1 } 50 }; 51 52 union thread_union cpu0_irqstack 53 __attribute__((__section__(".data..init_irqstack"))) = 54 { INIT_THREAD_INFO(init_task) }; 55 56 unsigned long thread_saved_pc(struct task_struct *task) 57 { 58 /* FIXME: Need to look up userspace_pid by cpu */ 59 return os_process_pc(userspace_pid[0]); 60 } 61 62 /* Changed in setup_arch, which is called in early boot */ 63 static char host_info[(__NEW_UTS_LEN + 1) * 5]; 64 65 static int show_cpuinfo(struct seq_file *m, void *v) 66 { 67 int index = 0; 68 69 #ifdef CONFIG_SMP 70 index = (struct cpuinfo_um *) v - cpu_data; 71 if (!cpu_online(index)) 72 return 0; 73 #endif 74 75 seq_printf(m, "processor\t: %d\n", index); 76 seq_printf(m, "vendor_id\t: User Mode Linux\n"); 77 seq_printf(m, "model name\t: UML\n"); 78 seq_printf(m, "mode\t\t: skas\n"); 79 seq_printf(m, "host\t\t: %s\n", host_info); 80 seq_printf(m, "bogomips\t: %lu.%02lu\n\n", 81 loops_per_jiffy/(500000/HZ), 82 (loops_per_jiffy/(5000/HZ)) % 100); 83 84 return 0; 85 } 86 87 static void *c_start(struct seq_file *m, loff_t *pos) 88 { 89 return *pos < NR_CPUS ? cpu_data + *pos : NULL; 90 } 91 92 static void *c_next(struct seq_file *m, void *v, loff_t *pos) 93 { 94 ++*pos; 95 return c_start(m, pos); 96 } 97 98 static void c_stop(struct seq_file *m, void *v) 99 { 100 } 101 102 const struct seq_operations cpuinfo_op = { 103 .start = c_start, 104 .next = c_next, 105 .stop = c_stop, 106 .show = show_cpuinfo, 107 }; 108 109 /* Set in linux_main */ 110 unsigned long uml_physmem; 111 EXPORT_SYMBOL(uml_physmem); 112 113 unsigned long uml_reserved; /* Also modified in mem_init */ 114 unsigned long start_vm; 115 unsigned long end_vm; 116 117 /* Set in uml_ncpus_setup */ 118 int ncpus = 1; 119 120 /* Set in early boot */ 121 static int have_root __initdata = 0; 122 123 /* Set in uml_mem_setup and modified in linux_main */ 124 long long physmem_size = 32 * 1024 * 1024; 125 126 static const char *usage_string = 127 "User Mode Linux v%s\n" 128 " available at http://user-mode-linux.sourceforge.net/\n\n"; 129 130 static int __init uml_version_setup(char *line, int *add) 131 { 132 printf("%s\n", init_utsname()->release); 133 exit(0); 134 135 return 0; 136 } 137 138 __uml_setup("--version", uml_version_setup, 139 "--version\n" 140 " Prints the version number of the kernel.\n\n" 141 ); 142 143 static int __init uml_root_setup(char *line, int *add) 144 { 145 have_root = 1; 146 return 0; 147 } 148 149 __uml_setup("root=", uml_root_setup, 150 "root=<file containing the root fs>\n" 151 " This is actually used by the generic kernel in exactly the same\n" 152 " way as in any other kernel. If you configure a number of block\n" 153 " devices and want to boot off something other than ubd0, you \n" 154 " would use something like:\n" 155 " root=/dev/ubd5\n\n" 156 ); 157 158 static int __init no_skas_debug_setup(char *line, int *add) 159 { 160 printf("'debug' is not necessary to gdb UML in skas mode - run \n"); 161 printf("'gdb linux'\n"); 162 163 return 0; 164 } 165 166 __uml_setup("debug", no_skas_debug_setup, 167 "debug\n" 168 " this flag is not needed to run gdb on UML in skas mode\n\n" 169 ); 170 171 #ifdef CONFIG_SMP 172 static int __init uml_ncpus_setup(char *line, int *add) 173 { 174 if (!sscanf(line, "%d", &ncpus)) { 175 printf("Couldn't parse [%s]\n", line); 176 return -1; 177 } 178 179 return 0; 180 } 181 182 __uml_setup("ncpus=", uml_ncpus_setup, 183 "ncpus=<# of desired CPUs>\n" 184 " This tells an SMP kernel how many virtual processors to start.\n\n" 185 ); 186 #endif 187 188 static int __init Usage(char *line, int *add) 189 { 190 const char **p; 191 192 printf(usage_string, init_utsname()->release); 193 p = &__uml_help_start; 194 while (p < &__uml_help_end) { 195 printf("%s", *p); 196 p++; 197 } 198 exit(0); 199 return 0; 200 } 201 202 __uml_setup("--help", Usage, 203 "--help\n" 204 " Prints this message.\n\n" 205 ); 206 207 static void __init uml_checksetup(char *line, int *add) 208 { 209 struct uml_param *p; 210 211 p = &__uml_setup_start; 212 while (p < &__uml_setup_end) { 213 size_t n; 214 215 n = strlen(p->str); 216 if (!strncmp(line, p->str, n) && p->setup_func(line + n, add)) 217 return; 218 p++; 219 } 220 } 221 222 static void __init uml_postsetup(void) 223 { 224 initcall_t *p; 225 226 p = &__uml_postsetup_start; 227 while (p < &__uml_postsetup_end) { 228 (*p)(); 229 p++; 230 } 231 return; 232 } 233 234 static int panic_exit(struct notifier_block *self, unsigned long unused1, 235 void *unused2) 236 { 237 bust_spinlocks(1); 238 bust_spinlocks(0); 239 uml_exitcode = 1; 240 os_dump_core(); 241 return 0; 242 } 243 244 static struct notifier_block panic_exit_notifier = { 245 .notifier_call = panic_exit, 246 .next = NULL, 247 .priority = 0 248 }; 249 250 /* Set during early boot */ 251 unsigned long task_size; 252 EXPORT_SYMBOL(task_size); 253 254 unsigned long host_task_size; 255 256 unsigned long brk_start; 257 unsigned long end_iomem; 258 EXPORT_SYMBOL(end_iomem); 259 260 #define MIN_VMALLOC (32 * 1024 * 1024) 261 262 extern char __binary_start; 263 264 int __init linux_main(int argc, char **argv) 265 { 266 unsigned long avail, diff; 267 unsigned long virtmem_size, max_physmem; 268 unsigned long stack; 269 unsigned int i; 270 int add; 271 char * mode; 272 273 for (i = 1; i < argc; i++) { 274 if ((i == 1) && (argv[i][0] == ' ')) 275 continue; 276 add = 1; 277 uml_checksetup(argv[i], &add); 278 if (add) 279 add_arg(argv[i]); 280 } 281 if (have_root == 0) 282 add_arg(DEFAULT_COMMAND_LINE); 283 284 host_task_size = os_get_top_address(); 285 /* 286 * TASK_SIZE needs to be PGDIR_SIZE aligned or else exit_mmap craps 287 * out 288 */ 289 task_size = host_task_size & PGDIR_MASK; 290 291 /* OS sanity checks that need to happen before the kernel runs */ 292 os_early_checks(); 293 294 can_do_skas(); 295 296 if (proc_mm && ptrace_faultinfo) 297 mode = "SKAS3"; 298 else 299 mode = "SKAS0"; 300 301 printf("UML running in %s mode\n", mode); 302 303 brk_start = (unsigned long) sbrk(0); 304 305 /* 306 * Increase physical memory size for exec-shield users 307 * so they actually get what they asked for. This should 308 * add zero for non-exec shield users 309 */ 310 311 diff = UML_ROUND_UP(brk_start) - UML_ROUND_UP(&_end); 312 if (diff > 1024 * 1024) { 313 printf("Adding %ld bytes to physical memory to account for " 314 "exec-shield gap\n", diff); 315 physmem_size += UML_ROUND_UP(brk_start) - UML_ROUND_UP(&_end); 316 } 317 318 uml_physmem = (unsigned long) &__binary_start & PAGE_MASK; 319 320 /* Reserve up to 4M after the current brk */ 321 uml_reserved = ROUND_4M(brk_start) + (1 << 22); 322 323 setup_machinename(init_utsname()->machine); 324 325 highmem = 0; 326 iomem_size = (iomem_size + PAGE_SIZE - 1) & PAGE_MASK; 327 max_physmem = TASK_SIZE - uml_physmem - iomem_size - MIN_VMALLOC; 328 329 /* 330 * Zones have to begin on a 1 << MAX_ORDER page boundary, 331 * so this makes sure that's true for highmem 332 */ 333 max_physmem &= ~((1 << (PAGE_SHIFT + MAX_ORDER)) - 1); 334 if (physmem_size + iomem_size > max_physmem) { 335 highmem = physmem_size + iomem_size - max_physmem; 336 physmem_size -= highmem; 337 #ifndef CONFIG_HIGHMEM 338 highmem = 0; 339 printf("CONFIG_HIGHMEM not enabled - physical memory shrunk " 340 "to %Lu bytes\n", physmem_size); 341 #endif 342 } 343 344 high_physmem = uml_physmem + physmem_size; 345 end_iomem = high_physmem + iomem_size; 346 high_memory = (void *) end_iomem; 347 348 start_vm = VMALLOC_START; 349 350 setup_physmem(uml_physmem, uml_reserved, physmem_size, highmem); 351 mem_total_pages(physmem_size, iomem_size, highmem); 352 353 virtmem_size = physmem_size; 354 stack = (unsigned long) argv; 355 stack &= ~(1024 * 1024 - 1); 356 avail = stack - start_vm; 357 if (physmem_size > avail) 358 virtmem_size = avail; 359 end_vm = start_vm + virtmem_size; 360 361 if (virtmem_size < physmem_size) 362 printf("Kernel virtual memory size shrunk to %lu bytes\n", 363 virtmem_size); 364 365 atomic_notifier_chain_register(&panic_notifier_list, 366 &panic_exit_notifier); 367 368 uml_postsetup(); 369 370 stack_protections((unsigned long) &init_thread_info); 371 os_flush_stdout(); 372 373 return start_uml(); 374 } 375 376 void __init setup_arch(char **cmdline_p) 377 { 378 paging_init(); 379 strlcpy(boot_command_line, command_line, COMMAND_LINE_SIZE); 380 *cmdline_p = command_line; 381 setup_hostinfo(host_info, sizeof host_info); 382 } 383 384 void __init check_bugs(void) 385 { 386 arch_check_bugs(); 387 os_check_bugs(); 388 } 389 390 void apply_alternatives(struct alt_instr *start, struct alt_instr *end) 391 { 392 } 393 394 #ifdef CONFIG_SMP 395 void alternatives_smp_module_add(struct module *mod, char *name, 396 void *locks, void *locks_end, 397 void *text, void *text_end) 398 { 399 } 400 401 void alternatives_smp_module_del(struct module *mod) 402 { 403 } 404 #endif 405