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
add_arg(char * arg)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
thread_saved_pc(struct task_struct * task)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
show_cpuinfo(struct seq_file * m,void * v)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
c_start(struct seq_file * m,loff_t * pos)87 static void *c_start(struct seq_file *m, loff_t *pos)
88 {
89 return *pos < NR_CPUS ? cpu_data + *pos : NULL;
90 }
91
c_next(struct seq_file * m,void * v,loff_t * pos)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
c_stop(struct seq_file * m,void * v)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
uml_version_setup(char * line,int * add)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
uml_root_setup(char * line,int * add)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
no_skas_debug_setup(char * line,int * add)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
uml_ncpus_setup(char * line,int * add)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
Usage(char * line,int * add)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
uml_checksetup(char * line,int * add)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
uml_postsetup(void)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
panic_exit(struct notifier_block * self,unsigned long unused1,void * unused2)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
linux_main(int argc,char ** argv)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
setup_arch(char ** cmdline_p)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
check_bugs(void)384 void __init check_bugs(void)
385 {
386 arch_check_bugs();
387 os_check_bugs();
388 }
389
apply_alternatives(struct alt_instr * start,struct alt_instr * end)390 void apply_alternatives(struct alt_instr *start, struct alt_instr *end)
391 {
392 }
393
394 #ifdef CONFIG_SMP
alternatives_smp_module_add(struct module * mod,char * name,void * locks,void * locks_end,void * text,void * text_end)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
alternatives_smp_module_del(struct module * mod)401 void alternatives_smp_module_del(struct module *mod)
402 {
403 }
404 #endif
405