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