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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#include <linux/random.h>
20
21#include <asm/processor.h>
22#include <asm/cpufeature.h>
23#include <asm/sections.h>
24#include <asm/setup.h>
25#include <as-layout.h>
26#include <arch.h>
27#include <init.h>
28#include <kern.h>
29#include <kern_util.h>
30#include <mem_user.h>
31#include <os.h>
32
33#include "um_arch.h"
34
35#define DEFAULT_COMMAND_LINE_ROOT "root=98:0"
36#define DEFAULT_COMMAND_LINE_CONSOLE "console=tty0"
37
38/* Changed in add_arg and setup_arch, which run before SMP is started */
39static char __initdata command_line[COMMAND_LINE_SIZE] = { 0 };
40
41static void __init add_arg(char *arg)
42{
43 if (strlen(command_line) + strlen(arg) + 1 > COMMAND_LINE_SIZE) {
44 os_warn("add_arg: Too many command line arguments!\n");
45 exit(1);
46 }
47 if (strlen(command_line) > 0)
48 strcat(command_line, " ");
49 strcat(command_line, arg);
50}
51
52/*
53 * These fields are initialized at boot time and not changed.
54 * XXX This structure is used only in the non-SMP case. Maybe this
55 * should be moved to smp.c.
56 */
57struct cpuinfo_um boot_cpu_data = {
58 .loops_per_jiffy = 0,
59 .ipi_pipe = { -1, -1 },
60 .cache_alignment = L1_CACHE_BYTES,
61 .x86_capability = { 0 }
62};
63
64EXPORT_SYMBOL(boot_cpu_data);
65
66union thread_union cpu0_irqstack
67 __section(".data..init_irqstack") =
68 { .thread_info = INIT_THREAD_INFO(init_task) };
69
70/* Changed in setup_arch, which is called in early boot */
71static char host_info[(__NEW_UTS_LEN + 1) * 5];
72
73static int show_cpuinfo(struct seq_file *m, void *v)
74{
75 int i = 0;
76
77 seq_printf(m, "processor\t: %d\n", i);
78 seq_printf(m, "vendor_id\t: User Mode Linux\n");
79 seq_printf(m, "model name\t: UML\n");
80 seq_printf(m, "mode\t\t: skas\n");
81 seq_printf(m, "host\t\t: %s\n", host_info);
82 seq_printf(m, "fpu\t\t: %s\n", cpu_has(&boot_cpu_data, X86_FEATURE_FPU) ? "yes" : "no");
83 seq_printf(m, "flags\t\t:");
84 for (i = 0; i < 32*NCAPINTS; i++)
85 if (cpu_has(&boot_cpu_data, i) && (x86_cap_flags[i] != NULL))
86 seq_printf(m, " %s", x86_cap_flags[i]);
87 seq_printf(m, "\n");
88 seq_printf(m, "cache_alignment\t: %d\n", boot_cpu_data.cache_alignment);
89 seq_printf(m, "bogomips\t: %lu.%02lu\n",
90 loops_per_jiffy/(500000/HZ),
91 (loops_per_jiffy/(5000/HZ)) % 100);
92
93
94 return 0;
95}
96
97static void *c_start(struct seq_file *m, loff_t *pos)
98{
99 return *pos < nr_cpu_ids ? cpu_data + *pos : NULL;
100}
101
102static void *c_next(struct seq_file *m, void *v, loff_t *pos)
103{
104 ++*pos;
105 return c_start(m, pos);
106}
107
108static void c_stop(struct seq_file *m, void *v)
109{
110}
111
112const struct seq_operations cpuinfo_op = {
113 .start = c_start,
114 .next = c_next,
115 .stop = c_stop,
116 .show = show_cpuinfo,
117};
118
119/* Set in linux_main */
120unsigned long uml_physmem;
121EXPORT_SYMBOL(uml_physmem);
122
123unsigned long uml_reserved; /* Also modified in mem_init */
124unsigned long start_vm;
125unsigned long end_vm;
126
127/* Set in uml_ncpus_setup */
128int ncpus = 1;
129
130/* Set in early boot */
131static int have_root __initdata;
132static int have_console __initdata;
133
134/* Set in uml_mem_setup and modified in linux_main */
135long long physmem_size = 64 * 1024 * 1024;
136EXPORT_SYMBOL(physmem_size);
137
138static const char *usage_string =
139"User Mode Linux v%s\n"
140" available at http://user-mode-linux.sourceforge.net/\n\n";
141
142static int __init uml_version_setup(char *line, int *add)
143{
144 /* Explicitly use printf() to show version in stdout */
145 printf("%s\n", init_utsname()->release);
146 exit(0);
147
148 return 0;
149}
150
151__uml_setup("--version", uml_version_setup,
152"--version\n"
153" Prints the version number of the kernel.\n\n"
154);
155
156static int __init uml_root_setup(char *line, int *add)
157{
158 have_root = 1;
159 return 0;
160}
161
162__uml_setup("root=", uml_root_setup,
163"root=<file containing the root fs>\n"
164" This is actually used by the generic kernel in exactly the same\n"
165" way as in any other kernel. If you configure a number of block\n"
166" devices and want to boot off something other than ubd0, you \n"
167" would use something like:\n"
168" root=/dev/ubd5\n\n"
169);
170
171static int __init no_skas_debug_setup(char *line, int *add)
172{
173 os_warn("'debug' is not necessary to gdb UML in skas mode - run\n");
174 os_warn("'gdb linux'\n");
175
176 return 0;
177}
178
179__uml_setup("debug", no_skas_debug_setup,
180"debug\n"
181" this flag is not needed to run gdb on UML in skas mode\n\n"
182);
183
184static int __init uml_console_setup(char *line, int *add)
185{
186 have_console = 1;
187 return 0;
188}
189
190__uml_setup("console=", uml_console_setup,
191"console=<preferred console>\n"
192" Specify the preferred console output driver\n\n"
193);
194
195static int __init Usage(char *line, int *add)
196{
197 const char **p;
198
199 printf(usage_string, init_utsname()->release);
200 p = &__uml_help_start;
201 /* Explicitly use printf() to show help in stdout */
202 while (p < &__uml_help_end) {
203 printf("%s", *p);
204 p++;
205 }
206 exit(0);
207 return 0;
208}
209
210__uml_setup("--help", Usage,
211"--help\n"
212" Prints this message.\n\n"
213);
214
215static void __init uml_checksetup(char *line, int *add)
216{
217 struct uml_param *p;
218
219 p = &__uml_setup_start;
220 while (p < &__uml_setup_end) {
221 size_t n;
222
223 n = strlen(p->str);
224 if (!strncmp(line, p->str, n) && p->setup_func(line + n, add))
225 return;
226 p++;
227 }
228}
229
230static void __init uml_postsetup(void)
231{
232 initcall_t *p;
233
234 p = &__uml_postsetup_start;
235 while (p < &__uml_postsetup_end) {
236 (*p)();
237 p++;
238 }
239 return;
240}
241
242static int panic_exit(struct notifier_block *self, unsigned long unused1,
243 void *unused2)
244{
245 kmsg_dump(KMSG_DUMP_PANIC);
246 bust_spinlocks(1);
247 bust_spinlocks(0);
248 uml_exitcode = 1;
249 os_dump_core();
250
251 return NOTIFY_DONE;
252}
253
254static struct notifier_block panic_exit_notifier = {
255 .notifier_call = panic_exit,
256 .priority = INT_MAX - 1, /* run as 2nd notifier, won't return */
257};
258
259void uml_finishsetup(void)
260{
261 atomic_notifier_chain_register(&panic_notifier_list,
262 &panic_exit_notifier);
263
264 uml_postsetup();
265
266 new_thread_handler();
267}
268
269/* Set during early boot */
270unsigned long stub_start;
271unsigned long task_size;
272EXPORT_SYMBOL(task_size);
273
274unsigned long host_task_size;
275
276unsigned long brk_start;
277unsigned long end_iomem;
278EXPORT_SYMBOL(end_iomem);
279
280#define MIN_VMALLOC (32 * 1024 * 1024)
281
282static void parse_host_cpu_flags(char *line)
283{
284 int i;
285 for (i = 0; i < 32*NCAPINTS; i++) {
286 if ((x86_cap_flags[i] != NULL) && strstr(line, x86_cap_flags[i]))
287 set_cpu_cap(&boot_cpu_data, i);
288 }
289}
290static void parse_cache_line(char *line)
291{
292 long res;
293 char *to_parse = strstr(line, ":");
294 if (to_parse) {
295 to_parse++;
296 while (*to_parse != 0 && isspace(*to_parse)) {
297 to_parse++;
298 }
299 if (kstrtoul(to_parse, 10, &res) == 0 && is_power_of_2(res))
300 boot_cpu_data.cache_alignment = res;
301 else
302 boot_cpu_data.cache_alignment = L1_CACHE_BYTES;
303 }
304}
305
306int __init linux_main(int argc, char **argv)
307{
308 unsigned long avail, diff;
309 unsigned long virtmem_size, max_physmem;
310 unsigned long stack;
311 unsigned int i;
312 int add;
313
314 for (i = 1; i < argc; i++) {
315 if ((i == 1) && (argv[i][0] == ' '))
316 continue;
317 add = 1;
318 uml_checksetup(argv[i], &add);
319 if (add)
320 add_arg(argv[i]);
321 }
322 if (have_root == 0)
323 add_arg(DEFAULT_COMMAND_LINE_ROOT);
324
325 if (have_console == 0)
326 add_arg(DEFAULT_COMMAND_LINE_CONSOLE);
327
328 host_task_size = os_get_top_address();
329 /* reserve two pages for the stubs */
330 host_task_size -= 2 * PAGE_SIZE;
331 stub_start = host_task_size;
332
333 /*
334 * TASK_SIZE needs to be PGDIR_SIZE aligned or else exit_mmap craps
335 * out
336 */
337 task_size = host_task_size & PGDIR_MASK;
338
339 /* OS sanity checks that need to happen before the kernel runs */
340 os_early_checks();
341
342 get_host_cpu_features(parse_host_cpu_flags, parse_cache_line);
343
344 brk_start = (unsigned long) sbrk(0);
345
346 /*
347 * Increase physical memory size for exec-shield users
348 * so they actually get what they asked for. This should
349 * add zero for non-exec shield users
350 */
351
352 diff = UML_ROUND_UP(brk_start) - UML_ROUND_UP(&_end);
353 if (diff > 1024 * 1024) {
354 os_info("Adding %ld bytes to physical memory to account for "
355 "exec-shield gap\n", diff);
356 physmem_size += UML_ROUND_UP(brk_start) - UML_ROUND_UP(&_end);
357 }
358
359 uml_physmem = (unsigned long) __binary_start & PAGE_MASK;
360
361 /* Reserve up to 4M after the current brk */
362 uml_reserved = ROUND_4M(brk_start) + (1 << 22);
363
364 setup_machinename(init_utsname()->machine);
365
366 highmem = 0;
367 iomem_size = (iomem_size + PAGE_SIZE - 1) & PAGE_MASK;
368 max_physmem = TASK_SIZE - uml_physmem - iomem_size - MIN_VMALLOC;
369
370 /*
371 * Zones have to begin on a 1 << MAX_ORDER page boundary,
372 * so this makes sure that's true for highmem
373 */
374 max_physmem &= ~((1 << (PAGE_SHIFT + MAX_ORDER)) - 1);
375 if (physmem_size + iomem_size > max_physmem) {
376 highmem = physmem_size + iomem_size - max_physmem;
377 physmem_size -= highmem;
378 }
379
380 high_physmem = uml_physmem + physmem_size;
381 end_iomem = high_physmem + iomem_size;
382 high_memory = (void *) end_iomem;
383
384 start_vm = VMALLOC_START;
385
386 virtmem_size = physmem_size;
387 stack = (unsigned long) argv;
388 stack &= ~(1024 * 1024 - 1);
389 avail = stack - start_vm;
390 if (physmem_size > avail)
391 virtmem_size = avail;
392 end_vm = start_vm + virtmem_size;
393
394 if (virtmem_size < physmem_size)
395 os_info("Kernel virtual memory size shrunk to %lu bytes\n",
396 virtmem_size);
397
398 os_flush_stdout();
399
400 return start_uml();
401}
402
403int __init __weak read_initrd(void)
404{
405 return 0;
406}
407
408void __init setup_arch(char **cmdline_p)
409{
410 u8 rng_seed[32];
411
412 stack_protections((unsigned long) &init_thread_info);
413 setup_physmem(uml_physmem, uml_reserved, physmem_size, highmem);
414 mem_total_pages(physmem_size, iomem_size, highmem);
415 uml_dtb_init();
416 read_initrd();
417
418 paging_init();
419 strscpy(boot_command_line, command_line, COMMAND_LINE_SIZE);
420 *cmdline_p = command_line;
421 setup_hostinfo(host_info, sizeof host_info);
422
423 if (os_getrandom(rng_seed, sizeof(rng_seed), 0) == sizeof(rng_seed)) {
424 add_bootloader_randomness(rng_seed, sizeof(rng_seed));
425 memzero_explicit(rng_seed, sizeof(rng_seed));
426 }
427}
428
429void __init check_bugs(void)
430{
431 arch_check_bugs();
432 os_check_bugs();
433}
434
435void apply_ibt_endbr(s32 *start, s32 *end)
436{
437}
438
439void apply_retpolines(s32 *start, s32 *end)
440{
441}
442
443void apply_returns(s32 *start, s32 *end)
444{
445}
446
447void apply_fineibt(s32 *start_retpoline, s32 *end_retpoline,
448 s32 *start_cfi, s32 *end_cfi)
449{
450}
451
452void apply_alternatives(struct alt_instr *start, struct alt_instr *end)
453{
454}
455
456void *text_poke(void *addr, const void *opcode, size_t len)
457{
458 /*
459 * In UML, the only reference to this function is in
460 * apply_relocate_add(), which shouldn't ever actually call this
461 * because UML doesn't have live patching.
462 */
463 WARN_ON(1);
464
465 return memcpy(addr, opcode, len);
466}
467
468void text_poke_sync(void)
469{
470}
471
472void uml_pm_wake(void)
473{
474 pm_system_wakeup();
475}
476
477#ifdef CONFIG_PM_SLEEP
478static int um_suspend_valid(suspend_state_t state)
479{
480 return state == PM_SUSPEND_MEM;
481}
482
483static int um_suspend_prepare(void)
484{
485 um_irqs_suspend();
486 return 0;
487}
488
489static int um_suspend_enter(suspend_state_t state)
490{
491 if (WARN_ON(state != PM_SUSPEND_MEM))
492 return -EINVAL;
493
494 /*
495 * This is identical to the idle sleep, but we've just
496 * (during suspend) turned off all interrupt sources
497 * except for the ones we want, so now we can only wake
498 * up on something we actually want to wake up on. All
499 * timing has also been suspended.
500 */
501 um_idle_sleep();
502 return 0;
503}
504
505static void um_suspend_finish(void)
506{
507 um_irqs_resume();
508}
509
510const struct platform_suspend_ops um_suspend_ops = {
511 .valid = um_suspend_valid,
512 .prepare = um_suspend_prepare,
513 .enter = um_suspend_enter,
514 .finish = um_suspend_finish,
515};
516
517static int init_pm_wake_signal(void)
518{
519 /*
520 * In external time-travel mode we can't use signals to wake up
521 * since that would mess with the scheduling. We'll have to do
522 * some additional work to support wakeup on virtio devices or
523 * similar, perhaps implementing a fake RTC controller that can
524 * trigger wakeup (and request the appropriate scheduling from
525 * the external scheduler when going to suspend.)
526 */
527 if (time_travel_mode != TT_MODE_EXTERNAL)
528 register_pm_wake_signal();
529
530 suspend_set_ops(&um_suspend_ops);
531
532 return 0;
533}
534
535late_initcall(init_pm_wake_signal);
536#endif
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/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/processor.h>
18#include <asm/sections.h>
19#include <asm/setup.h>
20#include <as-layout.h>
21#include <arch.h>
22#include <init.h>
23#include <kern.h>
24#include <kern_util.h>
25#include <mem_user.h>
26#include <os.h>
27
28#define DEFAULT_COMMAND_LINE "root=98:0"
29
30/* Changed in add_arg and setup_arch, which run before SMP is started */
31static char __initdata command_line[COMMAND_LINE_SIZE] = { 0 };
32
33static void __init add_arg(char *arg)
34{
35 if (strlen(command_line) + strlen(arg) + 1 > COMMAND_LINE_SIZE) {
36 os_warn("add_arg: Too many command line arguments!\n");
37 exit(1);
38 }
39 if (strlen(command_line) > 0)
40 strcat(command_line, " ");
41 strcat(command_line, arg);
42}
43
44/*
45 * These fields are initialized at boot time and not changed.
46 * XXX This structure is used only in the non-SMP case. Maybe this
47 * should be moved to smp.c.
48 */
49struct cpuinfo_um boot_cpu_data = {
50 .loops_per_jiffy = 0,
51 .ipi_pipe = { -1, -1 }
52};
53
54union thread_union cpu0_irqstack
55 __attribute__((__section__(".data..init_irqstack"))) =
56 { .thread_info = INIT_THREAD_INFO(init_task) };
57
58/* Changed in setup_arch, which is called in early boot */
59static char host_info[(__NEW_UTS_LEN + 1) * 5];
60
61static int show_cpuinfo(struct seq_file *m, void *v)
62{
63 int index = 0;
64
65 seq_printf(m, "processor\t: %d\n", index);
66 seq_printf(m, "vendor_id\t: User Mode Linux\n");
67 seq_printf(m, "model name\t: UML\n");
68 seq_printf(m, "mode\t\t: skas\n");
69 seq_printf(m, "host\t\t: %s\n", host_info);
70 seq_printf(m, "bogomips\t: %lu.%02lu\n\n",
71 loops_per_jiffy/(500000/HZ),
72 (loops_per_jiffy/(5000/HZ)) % 100);
73
74 return 0;
75}
76
77static void *c_start(struct seq_file *m, loff_t *pos)
78{
79 return *pos < NR_CPUS ? cpu_data + *pos : NULL;
80}
81
82static void *c_next(struct seq_file *m, void *v, loff_t *pos)
83{
84 ++*pos;
85 return c_start(m, pos);
86}
87
88static void c_stop(struct seq_file *m, void *v)
89{
90}
91
92const struct seq_operations cpuinfo_op = {
93 .start = c_start,
94 .next = c_next,
95 .stop = c_stop,
96 .show = show_cpuinfo,
97};
98
99/* Set in linux_main */
100unsigned long uml_physmem;
101EXPORT_SYMBOL(uml_physmem);
102
103unsigned long uml_reserved; /* Also modified in mem_init */
104unsigned long start_vm;
105unsigned long end_vm;
106
107/* Set in uml_ncpus_setup */
108int ncpus = 1;
109
110/* Set in early boot */
111static int have_root __initdata = 0;
112
113/* Set in uml_mem_setup and modified in linux_main */
114long long physmem_size = 32 * 1024 * 1024;
115EXPORT_SYMBOL(physmem_size);
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}
364
365void *text_poke(void *addr, const void *opcode, size_t len)
366{
367 /*
368 * In UML, the only reference to this function is in
369 * apply_relocate_add(), which shouldn't ever actually call this
370 * because UML doesn't have live patching.
371 */
372 WARN_ON(1);
373
374 return memcpy(addr, opcode, len);
375}
376
377void text_poke_sync(void)
378{
379}