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