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/setup.h>
17 #include <as-layout.h>
18 #include <arch.h>
19 #include <init.h>
20 #include <kern.h>
21 #include <kern_util.h>
22 #include <mem_user.h>
23 #include <os.h>
24
25 #define DEFAULT_COMMAND_LINE "root=98:0"
26
27 /* Changed in add_arg and setup_arch, which run before SMP is started */
28 static char __initdata command_line[COMMAND_LINE_SIZE] = { 0 };
29
add_arg(char * arg)30 static void __init add_arg(char *arg)
31 {
32 if (strlen(command_line) + strlen(arg) + 1 > COMMAND_LINE_SIZE) {
33 printf("add_arg: Too many command line arguments!\n");
34 exit(1);
35 }
36 if (strlen(command_line) > 0)
37 strcat(command_line, " ");
38 strcat(command_line, arg);
39 }
40
41 /*
42 * These fields are initialized at boot time and not changed.
43 * XXX This structure is used only in the non-SMP case. Maybe this
44 * should be moved to smp.c.
45 */
46 struct cpuinfo_um boot_cpu_data = {
47 .loops_per_jiffy = 0,
48 .ipi_pipe = { -1, -1 }
49 };
50
51 union thread_union cpu0_irqstack
52 __attribute__((__section__(".data..init_irqstack"))) =
53 { INIT_THREAD_INFO(init_task) };
54
thread_saved_pc(struct task_struct * task)55 unsigned long thread_saved_pc(struct task_struct *task)
56 {
57 /* FIXME: Need to look up userspace_pid by cpu */
58 return os_process_pc(userspace_pid[0]);
59 }
60
61 /* Changed in setup_arch, which is called in early boot */
62 static char host_info[(__NEW_UTS_LEN + 1) * 5];
63
show_cpuinfo(struct seq_file * m,void * v)64 static int show_cpuinfo(struct seq_file *m, void *v)
65 {
66 int index = 0;
67
68 #ifdef CONFIG_SMP
69 index = (struct cpuinfo_um *) v - cpu_data;
70 if (!cpu_online(index))
71 return 0;
72 #endif
73
74 seq_printf(m, "processor\t: %d\n", index);
75 seq_printf(m, "vendor_id\t: User Mode Linux\n");
76 seq_printf(m, "model name\t: UML\n");
77 seq_printf(m, "mode\t\t: skas\n");
78 seq_printf(m, "host\t\t: %s\n", host_info);
79 seq_printf(m, "bogomips\t: %lu.%02lu\n\n",
80 loops_per_jiffy/(500000/HZ),
81 (loops_per_jiffy/(5000/HZ)) % 100);
82
83 return 0;
84 }
85
c_start(struct seq_file * m,loff_t * pos)86 static void *c_start(struct seq_file *m, loff_t *pos)
87 {
88 return *pos < NR_CPUS ? cpu_data + *pos : NULL;
89 }
90
c_next(struct seq_file * m,void * v,loff_t * pos)91 static void *c_next(struct seq_file *m, void *v, loff_t *pos)
92 {
93 ++*pos;
94 return c_start(m, pos);
95 }
96
c_stop(struct seq_file * m,void * v)97 static void c_stop(struct seq_file *m, void *v)
98 {
99 }
100
101 const struct seq_operations cpuinfo_op = {
102 .start = c_start,
103 .next = c_next,
104 .stop = c_stop,
105 .show = show_cpuinfo,
106 };
107
108 /* Set in linux_main */
109 unsigned long uml_physmem;
110 EXPORT_SYMBOL(uml_physmem);
111
112 unsigned long uml_reserved; /* Also modified in mem_init */
113 unsigned long start_vm;
114 unsigned long end_vm;
115
116 /* Set in uml_ncpus_setup */
117 int ncpus = 1;
118
119 /* Set in early boot */
120 static int have_root __initdata = 0;
121
122 /* Set in uml_mem_setup and modified in linux_main */
123 long long physmem_size = 32 * 1024 * 1024;
124
125 static const char *usage_string =
126 "User Mode Linux v%s\n"
127 " available at http://user-mode-linux.sourceforge.net/\n\n";
128
uml_version_setup(char * line,int * add)129 static int __init uml_version_setup(char *line, int *add)
130 {
131 printf("%s\n", init_utsname()->release);
132 exit(0);
133
134 return 0;
135 }
136
137 __uml_setup("--version", uml_version_setup,
138 "--version\n"
139 " Prints the version number of the kernel.\n\n"
140 );
141
uml_root_setup(char * line,int * add)142 static int __init uml_root_setup(char *line, int *add)
143 {
144 have_root = 1;
145 return 0;
146 }
147
148 __uml_setup("root=", uml_root_setup,
149 "root=<file containing the root fs>\n"
150 " This is actually used by the generic kernel in exactly the same\n"
151 " way as in any other kernel. If you configure a number of block\n"
152 " devices and want to boot off something other than ubd0, you \n"
153 " would use something like:\n"
154 " root=/dev/ubd5\n\n"
155 );
156
no_skas_debug_setup(char * line,int * add)157 static int __init no_skas_debug_setup(char *line, int *add)
158 {
159 printf("'debug' is not necessary to gdb UML in skas mode - run \n");
160 printf("'gdb linux'\n");
161
162 return 0;
163 }
164
165 __uml_setup("debug", no_skas_debug_setup,
166 "debug\n"
167 " this flag is not needed to run gdb on UML in skas mode\n\n"
168 );
169
170 #ifdef CONFIG_SMP
uml_ncpus_setup(char * line,int * add)171 static int __init uml_ncpus_setup(char *line, int *add)
172 {
173 if (!sscanf(line, "%d", &ncpus)) {
174 printf("Couldn't parse [%s]\n", line);
175 return -1;
176 }
177
178 return 0;
179 }
180
181 __uml_setup("ncpus=", uml_ncpus_setup,
182 "ncpus=<# of desired CPUs>\n"
183 " This tells an SMP kernel how many virtual processors to start.\n\n"
184 );
185 #endif
186
Usage(char * line,int * add)187 static int __init Usage(char *line, int *add)
188 {
189 const char **p;
190
191 printf(usage_string, init_utsname()->release);
192 p = &__uml_help_start;
193 while (p < &__uml_help_end) {
194 printf("%s", *p);
195 p++;
196 }
197 exit(0);
198 return 0;
199 }
200
201 __uml_setup("--help", Usage,
202 "--help\n"
203 " Prints this message.\n\n"
204 );
205
uml_checksetup(char * line,int * add)206 static void __init uml_checksetup(char *line, int *add)
207 {
208 struct uml_param *p;
209
210 p = &__uml_setup_start;
211 while (p < &__uml_setup_end) {
212 size_t n;
213
214 n = strlen(p->str);
215 if (!strncmp(line, p->str, n) && p->setup_func(line + n, add))
216 return;
217 p++;
218 }
219 }
220
uml_postsetup(void)221 static void __init uml_postsetup(void)
222 {
223 initcall_t *p;
224
225 p = &__uml_postsetup_start;
226 while (p < &__uml_postsetup_end) {
227 (*p)();
228 p++;
229 }
230 return;
231 }
232
panic_exit(struct notifier_block * self,unsigned long unused1,void * unused2)233 static int panic_exit(struct notifier_block *self, unsigned long unused1,
234 void *unused2)
235 {
236 bust_spinlocks(1);
237 show_regs(&(current->thread.regs));
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 if (init_maps(physmem_size, iomem_size, highmem)) {
352 printf("Failed to allocate mem_map for %Lu bytes of physical "
353 "memory and %Lu bytes of highmem\n", physmem_size,
354 highmem);
355 exit(1);
356 }
357
358 virtmem_size = physmem_size;
359 stack = (unsigned long) argv;
360 stack &= ~(1024 * 1024 - 1);
361 avail = stack - start_vm;
362 if (physmem_size > avail)
363 virtmem_size = avail;
364 end_vm = start_vm + virtmem_size;
365
366 if (virtmem_size < physmem_size)
367 printf("Kernel virtual memory size shrunk to %lu bytes\n",
368 virtmem_size);
369
370 atomic_notifier_chain_register(&panic_notifier_list,
371 &panic_exit_notifier);
372
373 uml_postsetup();
374
375 stack_protections((unsigned long) &init_thread_info);
376 os_flush_stdout();
377
378 return start_uml();
379 }
380
setup_arch(char ** cmdline_p)381 void __init setup_arch(char **cmdline_p)
382 {
383 paging_init();
384 strlcpy(boot_command_line, command_line, COMMAND_LINE_SIZE);
385 *cmdline_p = command_line;
386 setup_hostinfo(host_info, sizeof host_info);
387 }
388
check_bugs(void)389 void __init check_bugs(void)
390 {
391 arch_check_bugs();
392 os_check_bugs();
393 }
394
apply_alternatives(struct alt_instr * start,struct alt_instr * end)395 void apply_alternatives(struct alt_instr *start, struct alt_instr *end)
396 {
397 }
398
399 #ifdef CONFIG_SMP
alternatives_smp_module_add(struct module * mod,char * name,void * locks,void * locks_end,void * text,void * text_end)400 void alternatives_smp_module_add(struct module *mod, char *name,
401 void *locks, void *locks_end,
402 void *text, void *text_end)
403 {
404 }
405
alternatives_smp_module_del(struct module * mod)406 void alternatives_smp_module_del(struct module *mod)
407 {
408 }
409 #endif
410