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 unsigned long uml_reserved; /* Also modified in mem_init */ 106 unsigned long start_vm; 107 unsigned long end_vm; 108 109 /* Set in uml_ncpus_setup */ 110 int ncpus = 1; 111 112 /* Set in early boot */ 113 static int have_root __initdata = 0; 114 115 /* Set in uml_mem_setup and modified in linux_main */ 116 long long physmem_size = 32 * 1024 * 1024; 117 118 static char *usage_string = 119 "User Mode Linux v%s\n" 120 " available at http://user-mode-linux.sourceforge.net/\n\n"; 121 122 static int __init uml_version_setup(char *line, int *add) 123 { 124 printf("%s\n", init_utsname()->release); 125 exit(0); 126 127 return 0; 128 } 129 130 __uml_setup("--version", uml_version_setup, 131 "--version\n" 132 " Prints the version number of the kernel.\n\n" 133 ); 134 135 static int __init uml_root_setup(char *line, int *add) 136 { 137 have_root = 1; 138 return 0; 139 } 140 141 __uml_setup("root=", uml_root_setup, 142 "root=<file containing the root fs>\n" 143 " This is actually used by the generic kernel in exactly the same\n" 144 " way as in any other kernel. If you configure a number of block\n" 145 " devices and want to boot off something other than ubd0, you \n" 146 " would use something like:\n" 147 " root=/dev/ubd5\n\n" 148 ); 149 150 static int __init no_skas_debug_setup(char *line, int *add) 151 { 152 printf("'debug' is not necessary to gdb UML in skas mode - run \n"); 153 printf("'gdb linux'"); 154 155 return 0; 156 } 157 158 __uml_setup("debug", no_skas_debug_setup, 159 "debug\n" 160 " this flag is not needed to run gdb on UML in skas mode\n\n" 161 ); 162 163 #ifdef CONFIG_SMP 164 static int __init uml_ncpus_setup(char *line, int *add) 165 { 166 if (!sscanf(line, "%d", &ncpus)) { 167 printf("Couldn't parse [%s]\n", line); 168 return -1; 169 } 170 171 return 0; 172 } 173 174 __uml_setup("ncpus=", uml_ncpus_setup, 175 "ncpus=<# of desired CPUs>\n" 176 " This tells an SMP kernel how many virtual processors to start.\n\n" 177 ); 178 #endif 179 180 static int __init Usage(char *line, int *add) 181 { 182 const char **p; 183 184 printf(usage_string, init_utsname()->release); 185 p = &__uml_help_start; 186 while (p < &__uml_help_end) { 187 printf("%s", *p); 188 p++; 189 } 190 exit(0); 191 return 0; 192 } 193 194 __uml_setup("--help", Usage, 195 "--help\n" 196 " Prints this message.\n\n" 197 ); 198 199 static void __init uml_checksetup(char *line, int *add) 200 { 201 struct uml_param *p; 202 203 p = &__uml_setup_start; 204 while (p < &__uml_setup_end) { 205 int n; 206 207 n = strlen(p->str); 208 if (!strncmp(line, p->str, n) && p->setup_func(line + n, add)) 209 return; 210 p++; 211 } 212 } 213 214 static void __init uml_postsetup(void) 215 { 216 initcall_t *p; 217 218 p = &__uml_postsetup_start; 219 while (p < &__uml_postsetup_end) { 220 (*p)(); 221 p++; 222 } 223 return; 224 } 225 226 static int panic_exit(struct notifier_block *self, unsigned long unused1, 227 void *unused2) 228 { 229 bust_spinlocks(1); 230 show_regs(&(current->thread.regs)); 231 bust_spinlocks(0); 232 uml_exitcode = 1; 233 os_dump_core(); 234 return 0; 235 } 236 237 static struct notifier_block panic_exit_notifier = { 238 .notifier_call = panic_exit, 239 .next = NULL, 240 .priority = 0 241 }; 242 243 /* Set during early boot */ 244 unsigned long task_size; 245 EXPORT_SYMBOL(task_size); 246 247 unsigned long host_task_size; 248 249 unsigned long brk_start; 250 unsigned long end_iomem; 251 EXPORT_SYMBOL(end_iomem); 252 253 #define MIN_VMALLOC (32 * 1024 * 1024) 254 255 extern char __binary_start; 256 257 int __init linux_main(int argc, char **argv) 258 { 259 unsigned long avail, diff; 260 unsigned long virtmem_size, max_physmem; 261 unsigned int i, add; 262 char * mode; 263 264 for (i = 1; i < argc; i++) { 265 if ((i == 1) && (argv[i][0] == ' ')) 266 continue; 267 add = 1; 268 uml_checksetup(argv[i], &add); 269 if (add) 270 add_arg(argv[i]); 271 } 272 if (have_root == 0) 273 add_arg(DEFAULT_COMMAND_LINE); 274 275 host_task_size = os_get_task_size(); 276 /* 277 * TASK_SIZE needs to be PGDIR_SIZE aligned or else exit_mmap craps 278 * out 279 */ 280 task_size = host_task_size & PGDIR_MASK; 281 282 /* OS sanity checks that need to happen before the kernel runs */ 283 os_early_checks(); 284 285 can_do_skas(); 286 287 if (proc_mm && ptrace_faultinfo) 288 mode = "SKAS3"; 289 else 290 mode = "SKAS0"; 291 292 printf("UML running in %s mode\n", mode); 293 294 brk_start = (unsigned long) sbrk(0); 295 296 /* 297 * Increase physical memory size for exec-shield users 298 * so they actually get what they asked for. This should 299 * add zero for non-exec shield users 300 */ 301 302 diff = UML_ROUND_UP(brk_start) - UML_ROUND_UP(&_end); 303 if (diff > 1024 * 1024) { 304 printf("Adding %ld bytes to physical memory to account for " 305 "exec-shield gap\n", diff); 306 physmem_size += UML_ROUND_UP(brk_start) - UML_ROUND_UP(&_end); 307 } 308 309 uml_physmem = (unsigned long) &__binary_start & PAGE_MASK; 310 311 /* Reserve up to 4M after the current brk */ 312 uml_reserved = ROUND_4M(brk_start) + (1 << 22); 313 314 setup_machinename(init_utsname()->machine); 315 316 highmem = 0; 317 iomem_size = (iomem_size + PAGE_SIZE - 1) & PAGE_MASK; 318 max_physmem = TASK_SIZE - uml_physmem - iomem_size - MIN_VMALLOC; 319 320 /* 321 * Zones have to begin on a 1 << MAX_ORDER page boundary, 322 * so this makes sure that's true for highmem 323 */ 324 max_physmem &= ~((1 << (PAGE_SHIFT + MAX_ORDER)) - 1); 325 if (physmem_size + iomem_size > max_physmem) { 326 highmem = physmem_size + iomem_size - max_physmem; 327 physmem_size -= highmem; 328 #ifndef CONFIG_HIGHMEM 329 highmem = 0; 330 printf("CONFIG_HIGHMEM not enabled - physical memory shrunk " 331 "to %Lu bytes\n", physmem_size); 332 #endif 333 } 334 335 high_physmem = uml_physmem + physmem_size; 336 end_iomem = high_physmem + iomem_size; 337 high_memory = (void *) end_iomem; 338 339 start_vm = VMALLOC_START; 340 341 setup_physmem(uml_physmem, uml_reserved, physmem_size, highmem); 342 if (init_maps(physmem_size, iomem_size, highmem)) { 343 printf("Failed to allocate mem_map for %Lu bytes of physical " 344 "memory and %Lu bytes of highmem\n", physmem_size, 345 highmem); 346 exit(1); 347 } 348 349 virtmem_size = physmem_size; 350 avail = TASK_SIZE - start_vm; 351 if (physmem_size > avail) 352 virtmem_size = avail; 353 end_vm = start_vm + virtmem_size; 354 355 if (virtmem_size < physmem_size) 356 printf("Kernel virtual memory size shrunk to %lu bytes\n", 357 virtmem_size); 358 359 atomic_notifier_chain_register(&panic_notifier_list, 360 &panic_exit_notifier); 361 362 uml_postsetup(); 363 364 stack_protections((unsigned long) &init_thread_info); 365 os_flush_stdout(); 366 367 return start_uml(); 368 } 369 370 void __init setup_arch(char **cmdline_p) 371 { 372 paging_init(); 373 strlcpy(boot_command_line, command_line, COMMAND_LINE_SIZE); 374 *cmdline_p = command_line; 375 setup_hostinfo(host_info, sizeof host_info); 376 } 377 378 void __init check_bugs(void) 379 { 380 arch_check_bugs(); 381 os_check_bugs(); 382 } 383 384 void apply_alternatives(struct alt_instr *start, struct alt_instr *end) 385 { 386 } 387 388 #ifdef CONFIG_SMP 389 void alternatives_smp_module_add(struct module *mod, char *name, 390 void *locks, void *locks_end, 391 void *text, void *text_end) 392 { 393 } 394 395 void alternatives_smp_module_del(struct module *mod) 396 { 397 } 398 #endif 399