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