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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 */
32static char __initdata command_line[COMMAND_LINE_SIZE] = { 0 };
33
34static void __init add_arg(char *arg)
35{
36 if (strlen(command_line) + strlen(arg) + 1 > COMMAND_LINE_SIZE) {
37 os_warn("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 */
50struct cpuinfo_um boot_cpu_data = {
51 .loops_per_jiffy = 0,
52 .ipi_pipe = { -1, -1 }
53};
54
55union thread_union cpu0_irqstack
56 __attribute__((__section__(".data..init_irqstack"))) =
57 { .thread_info = INIT_THREAD_INFO(init_task) };
58
59/* Changed in setup_arch, which is called in early boot */
60static char host_info[(__NEW_UTS_LEN + 1) * 5];
61
62static int show_cpuinfo(struct seq_file *m, void *v)
63{
64 int index = 0;
65
66 seq_printf(m, "processor\t: %d\n", index);
67 seq_printf(m, "vendor_id\t: User Mode Linux\n");
68 seq_printf(m, "model name\t: UML\n");
69 seq_printf(m, "mode\t\t: skas\n");
70 seq_printf(m, "host\t\t: %s\n", host_info);
71 seq_printf(m, "bogomips\t: %lu.%02lu\n\n",
72 loops_per_jiffy/(500000/HZ),
73 (loops_per_jiffy/(5000/HZ)) % 100);
74
75 return 0;
76}
77
78static void *c_start(struct seq_file *m, loff_t *pos)
79{
80 return *pos < NR_CPUS ? cpu_data + *pos : NULL;
81}
82
83static void *c_next(struct seq_file *m, void *v, loff_t *pos)
84{
85 ++*pos;
86 return c_start(m, pos);
87}
88
89static void c_stop(struct seq_file *m, void *v)
90{
91}
92
93const struct seq_operations cpuinfo_op = {
94 .start = c_start,
95 .next = c_next,
96 .stop = c_stop,
97 .show = show_cpuinfo,
98};
99
100/* Set in linux_main */
101unsigned long uml_physmem;
102EXPORT_SYMBOL(uml_physmem);
103
104unsigned long uml_reserved; /* Also modified in mem_init */
105unsigned long start_vm;
106unsigned long end_vm;
107
108/* Set in uml_ncpus_setup */
109int ncpus = 1;
110
111/* Set in early boot */
112static int have_root __initdata = 0;
113
114/* Set in uml_mem_setup and modified in linux_main */
115long long physmem_size = 32 * 1024 * 1024;
116
117static const char *usage_string =
118"User Mode Linux v%s\n"
119" available at http://user-mode-linux.sourceforge.net/\n\n";
120
121static int __init uml_version_setup(char *line, int *add)
122{
123 /* Explicitly use printf() to show version in stdout */
124 printf("%s\n", init_utsname()->release);
125 exit(0);
126
127 return 0;
128}
129
130__uml_setup("--version", uml_version_setup,
131"--version\n"
132" Prints the version number of the kernel.\n\n"
133);
134
135static int __init uml_root_setup(char *line, int *add)
136{
137 have_root = 1;
138 return 0;
139}
140
141__uml_setup("root=", uml_root_setup,
142"root=<file containing the root fs>\n"
143" This is actually used by the generic kernel in exactly the same\n"
144" way as in any other kernel. If you configure a number of block\n"
145" devices and want to boot off something other than ubd0, you \n"
146" would use something like:\n"
147" root=/dev/ubd5\n\n"
148);
149
150static int __init no_skas_debug_setup(char *line, int *add)
151{
152 os_warn("'debug' is not necessary to gdb UML in skas mode - run\n");
153 os_warn("'gdb linux'\n");
154
155 return 0;
156}
157
158__uml_setup("debug", no_skas_debug_setup,
159"debug\n"
160" this flag is not needed to run gdb on UML in skas mode\n\n"
161);
162
163static int __init Usage(char *line, int *add)
164{
165 const char **p;
166
167 printf(usage_string, init_utsname()->release);
168 p = &__uml_help_start;
169 /* Explicitly use printf() to show help in stdout */
170 while (p < &__uml_help_end) {
171 printf("%s", *p);
172 p++;
173 }
174 exit(0);
175 return 0;
176}
177
178__uml_setup("--help", Usage,
179"--help\n"
180" Prints this message.\n\n"
181);
182
183static void __init uml_checksetup(char *line, int *add)
184{
185 struct uml_param *p;
186
187 p = &__uml_setup_start;
188 while (p < &__uml_setup_end) {
189 size_t n;
190
191 n = strlen(p->str);
192 if (!strncmp(line, p->str, n) && p->setup_func(line + n, add))
193 return;
194 p++;
195 }
196}
197
198static void __init uml_postsetup(void)
199{
200 initcall_t *p;
201
202 p = &__uml_postsetup_start;
203 while (p < &__uml_postsetup_end) {
204 (*p)();
205 p++;
206 }
207 return;
208}
209
210static int panic_exit(struct notifier_block *self, unsigned long unused1,
211 void *unused2)
212{
213 kmsg_dump(KMSG_DUMP_PANIC);
214 bust_spinlocks(1);
215 bust_spinlocks(0);
216 uml_exitcode = 1;
217 os_dump_core();
218 return 0;
219}
220
221static struct notifier_block panic_exit_notifier = {
222 .notifier_call = panic_exit,
223 .next = NULL,
224 .priority = 0
225};
226
227void uml_finishsetup(void)
228{
229 atomic_notifier_chain_register(&panic_notifier_list,
230 &panic_exit_notifier);
231
232 uml_postsetup();
233
234 new_thread_handler();
235}
236
237/* Set during early boot */
238unsigned long task_size;
239EXPORT_SYMBOL(task_size);
240
241unsigned long host_task_size;
242
243unsigned long brk_start;
244unsigned long end_iomem;
245EXPORT_SYMBOL(end_iomem);
246
247#define MIN_VMALLOC (32 * 1024 * 1024)
248
249int __init linux_main(int argc, char **argv)
250{
251 unsigned long avail, diff;
252 unsigned long virtmem_size, max_physmem;
253 unsigned long stack;
254 unsigned int i;
255 int add;
256
257 for (i = 1; i < argc; i++) {
258 if ((i == 1) && (argv[i][0] == ' '))
259 continue;
260 add = 1;
261 uml_checksetup(argv[i], &add);
262 if (add)
263 add_arg(argv[i]);
264 }
265 if (have_root == 0)
266 add_arg(DEFAULT_COMMAND_LINE);
267
268 host_task_size = os_get_top_address();
269 /*
270 * TASK_SIZE needs to be PGDIR_SIZE aligned or else exit_mmap craps
271 * out
272 */
273 task_size = host_task_size & PGDIR_MASK;
274
275 /* OS sanity checks that need to happen before the kernel runs */
276 os_early_checks();
277
278 brk_start = (unsigned long) sbrk(0);
279
280 /*
281 * Increase physical memory size for exec-shield users
282 * so they actually get what they asked for. This should
283 * add zero for non-exec shield users
284 */
285
286 diff = UML_ROUND_UP(brk_start) - UML_ROUND_UP(&_end);
287 if (diff > 1024 * 1024) {
288 os_info("Adding %ld bytes to physical memory to account for "
289 "exec-shield gap\n", diff);
290 physmem_size += UML_ROUND_UP(brk_start) - UML_ROUND_UP(&_end);
291 }
292
293 uml_physmem = (unsigned long) __binary_start & PAGE_MASK;
294
295 /* Reserve up to 4M after the current brk */
296 uml_reserved = ROUND_4M(brk_start) + (1 << 22);
297
298 setup_machinename(init_utsname()->machine);
299
300 highmem = 0;
301 iomem_size = (iomem_size + PAGE_SIZE - 1) & PAGE_MASK;
302 max_physmem = TASK_SIZE - uml_physmem - iomem_size - MIN_VMALLOC;
303
304 /*
305 * Zones have to begin on a 1 << MAX_ORDER page boundary,
306 * so this makes sure that's true for highmem
307 */
308 max_physmem &= ~((1 << (PAGE_SHIFT + MAX_ORDER)) - 1);
309 if (physmem_size + iomem_size > max_physmem) {
310 highmem = physmem_size + iomem_size - max_physmem;
311 physmem_size -= highmem;
312 }
313
314 high_physmem = uml_physmem + physmem_size;
315 end_iomem = high_physmem + iomem_size;
316 high_memory = (void *) end_iomem;
317
318 start_vm = VMALLOC_START;
319
320 virtmem_size = physmem_size;
321 stack = (unsigned long) argv;
322 stack &= ~(1024 * 1024 - 1);
323 avail = stack - start_vm;
324 if (physmem_size > avail)
325 virtmem_size = avail;
326 end_vm = start_vm + virtmem_size;
327
328 if (virtmem_size < physmem_size)
329 os_info("Kernel virtual memory size shrunk to %lu bytes\n",
330 virtmem_size);
331
332 os_flush_stdout();
333
334 return start_uml();
335}
336
337int __init __weak read_initrd(void)
338{
339 return 0;
340}
341
342void __init setup_arch(char **cmdline_p)
343{
344 stack_protections((unsigned long) &init_thread_info);
345 setup_physmem(uml_physmem, uml_reserved, physmem_size, highmem);
346 mem_total_pages(physmem_size, iomem_size, highmem);
347 read_initrd();
348
349 paging_init();
350 strlcpy(boot_command_line, command_line, COMMAND_LINE_SIZE);
351 *cmdline_p = command_line;
352 setup_hostinfo(host_info, sizeof host_info);
353}
354
355void __init check_bugs(void)
356{
357 arch_check_bugs();
358 os_check_bugs();
359}
360
361void apply_alternatives(struct alt_instr *start, struct alt_instr *end)
362{
363}
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
4 */
5
6#include <linux/delay.h>
7#include <linux/init.h>
8#include <linux/mm.h>
9#include <linux/ctype.h>
10#include <linux/module.h>
11#include <linux/panic_notifier.h>
12#include <linux/seq_file.h>
13#include <linux/string.h>
14#include <linux/utsname.h>
15#include <linux/sched.h>
16#include <linux/sched/task.h>
17#include <linux/kmsg_dump.h>
18#include <linux/suspend.h>
19
20#include <asm/processor.h>
21#include <asm/cpufeature.h>
22#include <asm/sections.h>
23#include <asm/setup.h>
24#include <as-layout.h>
25#include <arch.h>
26#include <init.h>
27#include <kern.h>
28#include <kern_util.h>
29#include <mem_user.h>
30#include <os.h>
31
32#define DEFAULT_COMMAND_LINE_ROOT "root=98:0"
33#define DEFAULT_COMMAND_LINE_CONSOLE "console=tty"
34
35/* Changed in add_arg and setup_arch, which run before SMP is started */
36static char __initdata command_line[COMMAND_LINE_SIZE] = { 0 };
37
38static void __init add_arg(char *arg)
39{
40 if (strlen(command_line) + strlen(arg) + 1 > COMMAND_LINE_SIZE) {
41 os_warn("add_arg: Too many command line arguments!\n");
42 exit(1);
43 }
44 if (strlen(command_line) > 0)
45 strcat(command_line, " ");
46 strcat(command_line, arg);
47}
48
49/*
50 * These fields are initialized at boot time and not changed.
51 * XXX This structure is used only in the non-SMP case. Maybe this
52 * should be moved to smp.c.
53 */
54struct cpuinfo_um boot_cpu_data = {
55 .loops_per_jiffy = 0,
56 .ipi_pipe = { -1, -1 },
57 .cache_alignment = L1_CACHE_BYTES,
58 .x86_capability = { 0 }
59};
60
61EXPORT_SYMBOL(boot_cpu_data);
62
63union thread_union cpu0_irqstack
64 __section(".data..init_irqstack") =
65 { .thread_info = INIT_THREAD_INFO(init_task) };
66
67/* Changed in setup_arch, which is called in early boot */
68static char host_info[(__NEW_UTS_LEN + 1) * 5];
69
70static int show_cpuinfo(struct seq_file *m, void *v)
71{
72 int i = 0;
73
74 seq_printf(m, "processor\t: %d\n", i);
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, "fpu\t\t: %s\n", cpu_has(&boot_cpu_data, X86_FEATURE_FPU) ? "yes" : "no");
80 seq_printf(m, "flags\t\t:");
81 for (i = 0; i < 32*NCAPINTS; i++)
82 if (cpu_has(&boot_cpu_data, i) && (x86_cap_flags[i] != NULL))
83 seq_printf(m, " %s", x86_cap_flags[i]);
84 seq_printf(m, "\n");
85 seq_printf(m, "cache_alignment\t: %d\n", boot_cpu_data.cache_alignment);
86 seq_printf(m, "bogomips\t: %lu.%02lu\n",
87 loops_per_jiffy/(500000/HZ),
88 (loops_per_jiffy/(5000/HZ)) % 100);
89
90
91 return 0;
92}
93
94static void *c_start(struct seq_file *m, loff_t *pos)
95{
96 return *pos < NR_CPUS ? cpu_data + *pos : NULL;
97}
98
99static void *c_next(struct seq_file *m, void *v, loff_t *pos)
100{
101 ++*pos;
102 return c_start(m, pos);
103}
104
105static void c_stop(struct seq_file *m, void *v)
106{
107}
108
109const struct seq_operations cpuinfo_op = {
110 .start = c_start,
111 .next = c_next,
112 .stop = c_stop,
113 .show = show_cpuinfo,
114};
115
116/* Set in linux_main */
117unsigned long uml_physmem;
118EXPORT_SYMBOL(uml_physmem);
119
120unsigned long uml_reserved; /* Also modified in mem_init */
121unsigned long start_vm;
122unsigned long end_vm;
123
124/* Set in uml_ncpus_setup */
125int ncpus = 1;
126
127/* Set in early boot */
128static int have_root __initdata;
129static int have_console __initdata;
130
131/* Set in uml_mem_setup and modified in linux_main */
132long long physmem_size = 32 * 1024 * 1024;
133EXPORT_SYMBOL(physmem_size);
134
135static const char *usage_string =
136"User Mode Linux v%s\n"
137" available at http://user-mode-linux.sourceforge.net/\n\n";
138
139static int __init uml_version_setup(char *line, int *add)
140{
141 /* Explicitly use printf() to show version in stdout */
142 printf("%s\n", init_utsname()->release);
143 exit(0);
144
145 return 0;
146}
147
148__uml_setup("--version", uml_version_setup,
149"--version\n"
150" Prints the version number of the kernel.\n\n"
151);
152
153static int __init uml_root_setup(char *line, int *add)
154{
155 have_root = 1;
156 return 0;
157}
158
159__uml_setup("root=", uml_root_setup,
160"root=<file containing the root fs>\n"
161" This is actually used by the generic kernel in exactly the same\n"
162" way as in any other kernel. If you configure a number of block\n"
163" devices and want to boot off something other than ubd0, you \n"
164" would use something like:\n"
165" root=/dev/ubd5\n\n"
166);
167
168static int __init no_skas_debug_setup(char *line, int *add)
169{
170 os_warn("'debug' is not necessary to gdb UML in skas mode - run\n");
171 os_warn("'gdb linux'\n");
172
173 return 0;
174}
175
176__uml_setup("debug", no_skas_debug_setup,
177"debug\n"
178" this flag is not needed to run gdb on UML in skas mode\n\n"
179);
180
181static int __init uml_console_setup(char *line, int *add)
182{
183 have_console = 1;
184 return 0;
185}
186
187__uml_setup("console=", uml_console_setup,
188"console=<preferred console>\n"
189" Specify the preferred console output driver\n\n"
190);
191
192static int __init Usage(char *line, int *add)
193{
194 const char **p;
195
196 printf(usage_string, init_utsname()->release);
197 p = &__uml_help_start;
198 /* Explicitly use printf() to show help in stdout */
199 while (p < &__uml_help_end) {
200 printf("%s", *p);
201 p++;
202 }
203 exit(0);
204 return 0;
205}
206
207__uml_setup("--help", Usage,
208"--help\n"
209" Prints this message.\n\n"
210);
211
212static void __init uml_checksetup(char *line, int *add)
213{
214 struct uml_param *p;
215
216 p = &__uml_setup_start;
217 while (p < &__uml_setup_end) {
218 size_t n;
219
220 n = strlen(p->str);
221 if (!strncmp(line, p->str, n) && p->setup_func(line + n, add))
222 return;
223 p++;
224 }
225}
226
227static void __init uml_postsetup(void)
228{
229 initcall_t *p;
230
231 p = &__uml_postsetup_start;
232 while (p < &__uml_postsetup_end) {
233 (*p)();
234 p++;
235 }
236 return;
237}
238
239static int panic_exit(struct notifier_block *self, unsigned long unused1,
240 void *unused2)
241{
242 kmsg_dump(KMSG_DUMP_PANIC);
243 bust_spinlocks(1);
244 bust_spinlocks(0);
245 uml_exitcode = 1;
246 os_dump_core();
247 return 0;
248}
249
250static struct notifier_block panic_exit_notifier = {
251 .notifier_call = panic_exit,
252 .next = NULL,
253 .priority = 0
254};
255
256void uml_finishsetup(void)
257{
258 atomic_notifier_chain_register(&panic_notifier_list,
259 &panic_exit_notifier);
260
261 uml_postsetup();
262
263 new_thread_handler();
264}
265
266/* Set during early boot */
267unsigned long stub_start;
268unsigned long task_size;
269EXPORT_SYMBOL(task_size);
270
271unsigned long host_task_size;
272
273unsigned long brk_start;
274unsigned long end_iomem;
275EXPORT_SYMBOL(end_iomem);
276
277#define MIN_VMALLOC (32 * 1024 * 1024)
278
279static void parse_host_cpu_flags(char *line)
280{
281 int i;
282 for (i = 0; i < 32*NCAPINTS; i++) {
283 if ((x86_cap_flags[i] != NULL) && strstr(line, x86_cap_flags[i]))
284 set_cpu_cap(&boot_cpu_data, i);
285 }
286}
287static void parse_cache_line(char *line)
288{
289 long res;
290 char *to_parse = strstr(line, ":");
291 if (to_parse) {
292 to_parse++;
293 while (*to_parse != 0 && isspace(*to_parse)) {
294 to_parse++;
295 }
296 if (kstrtoul(to_parse, 10, &res) == 0 && is_power_of_2(res))
297 boot_cpu_data.cache_alignment = res;
298 else
299 boot_cpu_data.cache_alignment = L1_CACHE_BYTES;
300 }
301}
302
303int __init linux_main(int argc, char **argv)
304{
305 unsigned long avail, diff;
306 unsigned long virtmem_size, max_physmem;
307 unsigned long stack;
308 unsigned int i;
309 int add;
310
311 for (i = 1; i < argc; i++) {
312 if ((i == 1) && (argv[i][0] == ' '))
313 continue;
314 add = 1;
315 uml_checksetup(argv[i], &add);
316 if (add)
317 add_arg(argv[i]);
318 }
319 if (have_root == 0)
320 add_arg(DEFAULT_COMMAND_LINE_ROOT);
321
322 if (have_console == 0)
323 add_arg(DEFAULT_COMMAND_LINE_CONSOLE);
324
325 host_task_size = os_get_top_address();
326 /* reserve two pages for the stubs */
327 host_task_size -= 2 * PAGE_SIZE;
328 stub_start = host_task_size;
329
330 /*
331 * TASK_SIZE needs to be PGDIR_SIZE aligned or else exit_mmap craps
332 * out
333 */
334 task_size = host_task_size & PGDIR_MASK;
335
336 /* OS sanity checks that need to happen before the kernel runs */
337 os_early_checks();
338
339 get_host_cpu_features(parse_host_cpu_flags, parse_cache_line);
340
341 brk_start = (unsigned long) sbrk(0);
342
343 /*
344 * Increase physical memory size for exec-shield users
345 * so they actually get what they asked for. This should
346 * add zero for non-exec shield users
347 */
348
349 diff = UML_ROUND_UP(brk_start) - UML_ROUND_UP(&_end);
350 if (diff > 1024 * 1024) {
351 os_info("Adding %ld bytes to physical memory to account for "
352 "exec-shield gap\n", diff);
353 physmem_size += UML_ROUND_UP(brk_start) - UML_ROUND_UP(&_end);
354 }
355
356 uml_physmem = (unsigned long) __binary_start & PAGE_MASK;
357
358 /* Reserve up to 4M after the current brk */
359 uml_reserved = ROUND_4M(brk_start) + (1 << 22);
360
361 setup_machinename(init_utsname()->machine);
362
363 highmem = 0;
364 iomem_size = (iomem_size + PAGE_SIZE - 1) & PAGE_MASK;
365 max_physmem = TASK_SIZE - uml_physmem - iomem_size - MIN_VMALLOC;
366
367 /*
368 * Zones have to begin on a 1 << MAX_ORDER page boundary,
369 * so this makes sure that's true for highmem
370 */
371 max_physmem &= ~((1 << (PAGE_SHIFT + MAX_ORDER)) - 1);
372 if (physmem_size + iomem_size > max_physmem) {
373 highmem = physmem_size + iomem_size - max_physmem;
374 physmem_size -= highmem;
375 }
376
377 high_physmem = uml_physmem + physmem_size;
378 end_iomem = high_physmem + iomem_size;
379 high_memory = (void *) end_iomem;
380
381 start_vm = VMALLOC_START;
382
383 virtmem_size = physmem_size;
384 stack = (unsigned long) argv;
385 stack &= ~(1024 * 1024 - 1);
386 avail = stack - start_vm;
387 if (physmem_size > avail)
388 virtmem_size = avail;
389 end_vm = start_vm + virtmem_size;
390
391 if (virtmem_size < physmem_size)
392 os_info("Kernel virtual memory size shrunk to %lu bytes\n",
393 virtmem_size);
394
395 os_flush_stdout();
396
397 return start_uml();
398}
399
400int __init __weak read_initrd(void)
401{
402 return 0;
403}
404
405void __init setup_arch(char **cmdline_p)
406{
407 stack_protections((unsigned long) &init_thread_info);
408 setup_physmem(uml_physmem, uml_reserved, physmem_size, highmem);
409 mem_total_pages(physmem_size, iomem_size, highmem);
410 read_initrd();
411
412 paging_init();
413 strlcpy(boot_command_line, command_line, COMMAND_LINE_SIZE);
414 *cmdline_p = command_line;
415 setup_hostinfo(host_info, sizeof host_info);
416}
417
418void __init check_bugs(void)
419{
420 arch_check_bugs();
421 os_check_bugs();
422}
423
424void apply_alternatives(struct alt_instr *start, struct alt_instr *end)
425{
426}
427
428void *text_poke(void *addr, const void *opcode, size_t len)
429{
430 /*
431 * In UML, the only reference to this function is in
432 * apply_relocate_add(), which shouldn't ever actually call this
433 * because UML doesn't have live patching.
434 */
435 WARN_ON(1);
436
437 return memcpy(addr, opcode, len);
438}
439
440void text_poke_sync(void)
441{
442}
443
444void uml_pm_wake(void)
445{
446 pm_system_wakeup();
447}
448
449#ifdef CONFIG_PM_SLEEP
450static int um_suspend_valid(suspend_state_t state)
451{
452 return state == PM_SUSPEND_MEM;
453}
454
455static int um_suspend_prepare(void)
456{
457 um_irqs_suspend();
458 return 0;
459}
460
461static int um_suspend_enter(suspend_state_t state)
462{
463 if (WARN_ON(state != PM_SUSPEND_MEM))
464 return -EINVAL;
465
466 /*
467 * This is identical to the idle sleep, but we've just
468 * (during suspend) turned off all interrupt sources
469 * except for the ones we want, so now we can only wake
470 * up on something we actually want to wake up on. All
471 * timing has also been suspended.
472 */
473 um_idle_sleep();
474 return 0;
475}
476
477static void um_suspend_finish(void)
478{
479 um_irqs_resume();
480}
481
482const struct platform_suspend_ops um_suspend_ops = {
483 .valid = um_suspend_valid,
484 .prepare = um_suspend_prepare,
485 .enter = um_suspend_enter,
486 .finish = um_suspend_finish,
487};
488
489static int init_pm_wake_signal(void)
490{
491 /*
492 * In external time-travel mode we can't use signals to wake up
493 * since that would mess with the scheduling. We'll have to do
494 * some additional work to support wakeup on virtio devices or
495 * similar, perhaps implementing a fake RTC controller that can
496 * trigger wakeup (and request the appropriate scheduling from
497 * the external scheduler when going to suspend.)
498 */
499 if (time_travel_mode != TT_MODE_EXTERNAL)
500 register_pm_wake_signal();
501
502 suspend_set_ops(&um_suspend_ops);
503
504 return 0;
505}
506
507late_initcall(init_pm_wake_signal);
508#endif