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 */
30static char __initdata command_line[COMMAND_LINE_SIZE] = { 0 };
31
32static 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 */
48struct cpuinfo_um boot_cpu_data = {
49	.loops_per_jiffy	= 0,
50	.ipi_pipe		= { -1, -1 }
51};
52
53union thread_union cpu0_irqstack
54	__attribute__((__section__(".data..init_irqstack"))) =
55		{ INIT_THREAD_INFO(init_task) };
56
57unsigned 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 */
64static char host_info[(__NEW_UTS_LEN + 1) * 5];
65
66static 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
82static void *c_start(struct seq_file *m, loff_t *pos)
83{
84	return *pos < NR_CPUS ? cpu_data + *pos : NULL;
85}
86
87static void *c_next(struct seq_file *m, void *v, loff_t *pos)
88{
89	++*pos;
90	return c_start(m, pos);
91}
92
93static void c_stop(struct seq_file *m, void *v)
94{
95}
96
97const 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 */
105unsigned long uml_physmem;
106EXPORT_SYMBOL(uml_physmem);
107
108unsigned long uml_reserved; /* Also modified in mem_init */
109unsigned long start_vm;
110unsigned long end_vm;
111
112/* Set in uml_ncpus_setup */
113int ncpus = 1;
114
115/* Set in early boot */
116static int have_root __initdata = 0;
117
118/* Set in uml_mem_setup and modified in linux_main */
119long long physmem_size = 32 * 1024 * 1024;
120
121static const char *usage_string =
122"User Mode Linux v%s\n"
123"	available at http://user-mode-linux.sourceforge.net/\n\n";
124
125static 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
138static 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
153static 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
166static 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
185static 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
200static 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
212static 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
223static struct notifier_block panic_exit_notifier = {
224	.notifier_call 		= panic_exit,
225	.next 			= NULL,
226	.priority 		= 0
227};
228
229void 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 */
240unsigned long task_size;
241EXPORT_SYMBOL(task_size);
242
243unsigned long host_task_size;
244
245unsigned long brk_start;
246unsigned long end_iomem;
247EXPORT_SYMBOL(end_iomem);
248
249#define MIN_VMALLOC (32 * 1024 * 1024)
250
251extern char __binary_start;
252
253int __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	setup_physmem(uml_physmem, uml_reserved, physmem_size, highmem);
325	mem_total_pages(physmem_size, iomem_size, highmem);
326
327	virtmem_size = physmem_size;
328	stack = (unsigned long) argv;
329	stack &= ~(1024 * 1024 - 1);
330	avail = stack - start_vm;
331	if (physmem_size > avail)
332		virtmem_size = avail;
333	end_vm = start_vm + virtmem_size;
334
335	if (virtmem_size < physmem_size)
336		printf("Kernel virtual memory size shrunk to %lu bytes\n",
337		       virtmem_size);
338
339	stack_protections((unsigned long) &init_thread_info);
340	os_flush_stdout();
341
342	return start_uml();
343}
344
345void __init setup_arch(char **cmdline_p)
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
353void __init check_bugs(void)
354{
355	arch_check_bugs();
356	os_check_bugs();
357}
358
359void apply_alternatives(struct alt_instr *start, struct alt_instr *end)
360{
361}
362