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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/cpu.h>
7#include <linux/delay.h>
8#include <linux/init.h>
9#include <linux/mm.h>
10#include <linux/ctype.h>
11#include <linux/module.h>
12#include <linux/panic_notifier.h>
13#include <linux/seq_file.h>
14#include <linux/string.h>
15#include <linux/utsname.h>
16#include <linux/sched.h>
17#include <linux/sched/task.h>
18#include <linux/kmsg_dump.h>
19#include <linux/suspend.h>
20#include <linux/random.h>
21
22#include <asm/processor.h>
23#include <asm/cpufeature.h>
24#include <asm/sections.h>
25#include <asm/setup.h>
26#include <asm/text-patching.h>
27#include <as-layout.h>
28#include <arch.h>
29#include <init.h>
30#include <kern.h>
31#include <kern_util.h>
32#include <mem_user.h>
33#include <os.h>
34
35#include "um_arch.h"
36
37#define DEFAULT_COMMAND_LINE_ROOT "root=98:0"
38#define DEFAULT_COMMAND_LINE_CONSOLE "console=tty0"
39
40/* Changed in add_arg and setup_arch, which run before SMP is started */
41static char __initdata command_line[COMMAND_LINE_SIZE] = { 0 };
42
43static void __init add_arg(char *arg)
44{
45 if (strlen(command_line) + strlen(arg) + 1 > COMMAND_LINE_SIZE) {
46 os_warn("add_arg: Too many command line arguments!\n");
47 exit(1);
48 }
49 if (strlen(command_line) > 0)
50 strcat(command_line, " ");
51 strcat(command_line, arg);
52}
53
54/*
55 * These fields are initialized at boot time and not changed.
56 * XXX This structure is used only in the non-SMP case. Maybe this
57 * should be moved to smp.c.
58 */
59struct cpuinfo_um boot_cpu_data = {
60 .loops_per_jiffy = 0,
61 .ipi_pipe = { -1, -1 },
62 .cache_alignment = L1_CACHE_BYTES,
63 .x86_capability = { 0 }
64};
65
66EXPORT_SYMBOL(boot_cpu_data);
67
68
69/* Changed in setup_arch, which is called in early boot */
70static char host_info[(__NEW_UTS_LEN + 1) * 5];
71
72static int show_cpuinfo(struct seq_file *m, void *v)
73{
74 int i = 0;
75
76 seq_printf(m, "processor\t: %d\n", i);
77 seq_printf(m, "vendor_id\t: User Mode Linux\n");
78 seq_printf(m, "model name\t: UML\n");
79 seq_printf(m, "mode\t\t: skas\n");
80 seq_printf(m, "host\t\t: %s\n", host_info);
81 seq_printf(m, "fpu\t\t: %s\n", cpu_has(&boot_cpu_data, X86_FEATURE_FPU) ? "yes" : "no");
82 seq_printf(m, "flags\t\t:");
83 for (i = 0; i < 32*NCAPINTS; i++)
84 if (cpu_has(&boot_cpu_data, i) && (x86_cap_flags[i] != NULL))
85 seq_printf(m, " %s", x86_cap_flags[i]);
86 seq_printf(m, "\n");
87 seq_printf(m, "cache_alignment\t: %d\n", boot_cpu_data.cache_alignment);
88 seq_printf(m, "bogomips\t: %lu.%02lu\n",
89 loops_per_jiffy/(500000/HZ),
90 (loops_per_jiffy/(5000/HZ)) % 100);
91
92
93 return 0;
94}
95
96static void *c_start(struct seq_file *m, loff_t *pos)
97{
98 return *pos < nr_cpu_ids ? &boot_cpu_data + *pos : NULL;
99}
100
101static void *c_next(struct seq_file *m, void *v, loff_t *pos)
102{
103 ++*pos;
104 return c_start(m, pos);
105}
106
107static void c_stop(struct seq_file *m, void *v)
108{
109}
110
111const struct seq_operations cpuinfo_op = {
112 .start = c_start,
113 .next = c_next,
114 .stop = c_stop,
115 .show = show_cpuinfo,
116};
117
118/* Set in linux_main */
119unsigned long uml_physmem;
120EXPORT_SYMBOL(uml_physmem);
121
122unsigned long uml_reserved; /* Also modified in mem_init */
123unsigned long start_vm;
124unsigned long end_vm;
125
126/* Set in early boot */
127static int have_root __initdata;
128static int have_console __initdata;
129
130/* Set in uml_mem_setup and modified in linux_main */
131unsigned long long physmem_size = 64 * 1024 * 1024;
132EXPORT_SYMBOL(physmem_size);
133
134static const char *usage_string =
135"User Mode Linux v%s\n"
136" available at http://user-mode-linux.sourceforge.net/\n\n";
137
138static int __init uml_version_setup(char *line, int *add)
139{
140 /* Explicitly use printf() to show version in stdout */
141 printf("%s\n", init_utsname()->release);
142 exit(0);
143
144 return 0;
145}
146
147__uml_setup("--version", uml_version_setup,
148"--version\n"
149" Prints the version number of the kernel.\n\n"
150);
151
152static int __init uml_root_setup(char *line, int *add)
153{
154 have_root = 1;
155 return 0;
156}
157
158__uml_setup("root=", uml_root_setup,
159"root=<file containing the root fs>\n"
160" This is actually used by the generic kernel in exactly the same\n"
161" way as in any other kernel. If you configure a number of block\n"
162" devices and want to boot off something other than ubd0, you \n"
163" would use something like:\n"
164" root=/dev/ubd5\n\n"
165);
166
167static int __init uml_console_setup(char *line, int *add)
168{
169 have_console = 1;
170 return 0;
171}
172
173__uml_setup("console=", uml_console_setup,
174"console=<preferred console>\n"
175" Specify the preferred console output driver\n\n"
176);
177
178static int __init Usage(char *line, int *add)
179{
180 const char **p;
181
182 printf(usage_string, init_utsname()->release);
183 p = &__uml_help_start;
184 /* Explicitly use printf() to show help in stdout */
185 while (p < &__uml_help_end) {
186 printf("%s", *p);
187 p++;
188 }
189 exit(0);
190 return 0;
191}
192
193__uml_setup("--help", Usage,
194"--help\n"
195" Prints this message.\n\n"
196);
197
198static void __init uml_checksetup(char *line, int *add)
199{
200 struct uml_param *p;
201
202 p = &__uml_setup_start;
203 while (p < &__uml_setup_end) {
204 size_t n;
205
206 n = strlen(p->str);
207 if (!strncmp(line, p->str, n) && p->setup_func(line + n, add))
208 return;
209 p++;
210 }
211}
212
213static void __init uml_postsetup(void)
214{
215 initcall_t *p;
216
217 p = &__uml_postsetup_start;
218 while (p < &__uml_postsetup_end) {
219 (*p)();
220 p++;
221 }
222 return;
223}
224
225static int panic_exit(struct notifier_block *self, unsigned long unused1,
226 void *unused2)
227{
228 kmsg_dump(KMSG_DUMP_PANIC);
229 bust_spinlocks(1);
230 bust_spinlocks(0);
231 uml_exitcode = 1;
232 os_dump_core();
233
234 return NOTIFY_DONE;
235}
236
237static struct notifier_block panic_exit_notifier = {
238 .notifier_call = panic_exit,
239 .priority = INT_MAX - 1, /* run as 2nd notifier, won't return */
240};
241
242void uml_finishsetup(void)
243{
244 cpu_tasks[0] = &init_task;
245
246 atomic_notifier_chain_register(&panic_notifier_list,
247 &panic_exit_notifier);
248
249 uml_postsetup();
250
251 new_thread_handler();
252}
253
254/* Set during early boot */
255unsigned long stub_start;
256unsigned long task_size;
257EXPORT_SYMBOL(task_size);
258
259unsigned long host_task_size;
260
261unsigned long brk_start;
262unsigned long end_iomem;
263EXPORT_SYMBOL(end_iomem);
264
265#define MIN_VMALLOC (32 * 1024 * 1024)
266
267static void parse_host_cpu_flags(char *line)
268{
269 int i;
270 for (i = 0; i < 32*NCAPINTS; i++) {
271 if ((x86_cap_flags[i] != NULL) && strstr(line, x86_cap_flags[i]))
272 set_cpu_cap(&boot_cpu_data, i);
273 }
274}
275static void parse_cache_line(char *line)
276{
277 long res;
278 char *to_parse = strstr(line, ":");
279 if (to_parse) {
280 to_parse++;
281 while (*to_parse != 0 && isspace(*to_parse)) {
282 to_parse++;
283 }
284 if (kstrtoul(to_parse, 10, &res) == 0 && is_power_of_2(res))
285 boot_cpu_data.cache_alignment = res;
286 else
287 boot_cpu_data.cache_alignment = L1_CACHE_BYTES;
288 }
289}
290
291static unsigned long get_top_address(char **envp)
292{
293 unsigned long top_addr = (unsigned long) &top_addr;
294 int i;
295
296 /* The earliest variable should be after the program name in ELF */
297 for (i = 0; envp[i]; i++) {
298 if ((unsigned long) envp[i] > top_addr)
299 top_addr = (unsigned long) envp[i];
300 }
301
302 top_addr &= ~(UM_KERN_PAGE_SIZE - 1);
303 top_addr += UM_KERN_PAGE_SIZE;
304
305 return top_addr;
306}
307
308int __init linux_main(int argc, char **argv, char **envp)
309{
310 unsigned long avail, diff;
311 unsigned long virtmem_size, max_physmem;
312 unsigned long stack;
313 unsigned int i;
314 int add;
315
316 for (i = 1; i < argc; i++) {
317 if ((i == 1) && (argv[i][0] == ' '))
318 continue;
319 add = 1;
320 uml_checksetup(argv[i], &add);
321 if (add)
322 add_arg(argv[i]);
323 }
324 if (have_root == 0)
325 add_arg(DEFAULT_COMMAND_LINE_ROOT);
326
327 if (have_console == 0)
328 add_arg(DEFAULT_COMMAND_LINE_CONSOLE);
329
330 host_task_size = get_top_address(envp);
331 /* reserve a few pages for the stubs */
332 stub_start = host_task_size - STUB_DATA_PAGES * PAGE_SIZE;
333 /* another page for the code portion */
334 stub_start -= PAGE_SIZE;
335 host_task_size = stub_start;
336
337 /* Limit TASK_SIZE to what is addressable by the page table */
338 task_size = host_task_size;
339 if (task_size > (unsigned long long) PTRS_PER_PGD * PGDIR_SIZE)
340 task_size = PTRS_PER_PGD * PGDIR_SIZE;
341
342 /*
343 * TASK_SIZE needs to be PGDIR_SIZE aligned or else exit_mmap craps
344 * out
345 */
346 task_size = task_size & PGDIR_MASK;
347
348 /* OS sanity checks that need to happen before the kernel runs */
349 os_early_checks();
350
351 get_host_cpu_features(parse_host_cpu_flags, parse_cache_line);
352
353 brk_start = (unsigned long) sbrk(0);
354
355 /*
356 * Increase physical memory size for exec-shield users
357 * so they actually get what they asked for. This should
358 * add zero for non-exec shield users
359 */
360
361 diff = UML_ROUND_UP(brk_start) - UML_ROUND_UP(&_end);
362 if (diff > 1024 * 1024) {
363 os_info("Adding %ld bytes to physical memory to account for "
364 "exec-shield gap\n", diff);
365 physmem_size += UML_ROUND_UP(brk_start) - UML_ROUND_UP(&_end);
366 }
367
368 uml_physmem = (unsigned long) __binary_start & PAGE_MASK;
369
370 /* Reserve up to 4M after the current brk */
371 uml_reserved = ROUND_4M(brk_start) + (1 << 22);
372
373 setup_machinename(init_utsname()->machine);
374
375 physmem_size = (physmem_size + PAGE_SIZE - 1) & PAGE_MASK;
376 iomem_size = (iomem_size + PAGE_SIZE - 1) & PAGE_MASK;
377
378 max_physmem = TASK_SIZE - uml_physmem - iomem_size - MIN_VMALLOC;
379
380 if (physmem_size + iomem_size > max_physmem) {
381 physmem_size = max_physmem - iomem_size;
382 os_info("Physical memory size shrunk to %llu bytes\n",
383 physmem_size);
384 }
385
386 high_physmem = uml_physmem + physmem_size;
387 end_iomem = high_physmem + iomem_size;
388 high_memory = (void *) end_iomem;
389
390 start_vm = VMALLOC_START;
391
392 virtmem_size = physmem_size;
393 stack = (unsigned long) argv;
394 stack &= ~(1024 * 1024 - 1);
395 avail = stack - start_vm;
396 if (physmem_size > avail)
397 virtmem_size = avail;
398 end_vm = start_vm + virtmem_size;
399
400 if (virtmem_size < physmem_size)
401 os_info("Kernel virtual memory size shrunk to %lu bytes\n",
402 virtmem_size);
403
404 arch_task_struct_size = sizeof(struct task_struct) + host_fp_size;
405
406 os_flush_stdout();
407
408 return start_uml();
409}
410
411int __init __weak read_initrd(void)
412{
413 return 0;
414}
415
416void __init setup_arch(char **cmdline_p)
417{
418 u8 rng_seed[32];
419
420 stack_protections((unsigned long) init_task.stack);
421 setup_physmem(uml_physmem, uml_reserved, physmem_size);
422 mem_total_pages(physmem_size, iomem_size);
423 uml_dtb_init();
424 read_initrd();
425
426 paging_init();
427 strscpy(boot_command_line, command_line, COMMAND_LINE_SIZE);
428 *cmdline_p = command_line;
429 setup_hostinfo(host_info, sizeof host_info);
430
431 if (os_getrandom(rng_seed, sizeof(rng_seed), 0) == sizeof(rng_seed)) {
432 add_bootloader_randomness(rng_seed, sizeof(rng_seed));
433 memzero_explicit(rng_seed, sizeof(rng_seed));
434 }
435}
436
437void __init arch_cpu_finalize_init(void)
438{
439 arch_check_bugs();
440 os_check_bugs();
441}
442
443void apply_seal_endbr(s32 *start, s32 *end, struct module *mod)
444{
445}
446
447void apply_retpolines(s32 *start, s32 *end, struct module *mod)
448{
449}
450
451void apply_returns(s32 *start, s32 *end, struct module *mod)
452{
453}
454
455void apply_fineibt(s32 *start_retpoline, s32 *end_retpoline,
456 s32 *start_cfi, s32 *end_cfi, struct module *mod)
457{
458}
459
460void apply_alternatives(struct alt_instr *start, struct alt_instr *end,
461 struct module *mod)
462{
463}
464
465void *text_poke(void *addr, const void *opcode, size_t len)
466{
467 /*
468 * In UML, the only reference to this function is in
469 * apply_relocate_add(), which shouldn't ever actually call this
470 * because UML doesn't have live patching.
471 */
472 WARN_ON(1);
473
474 return memcpy(addr, opcode, len);
475}
476
477void *text_poke_copy(void *addr, const void *opcode, size_t len)
478{
479 return text_poke(addr, opcode, len);
480}
481
482void text_poke_sync(void)
483{
484}
485
486void uml_pm_wake(void)
487{
488 pm_system_wakeup();
489}
490
491#ifdef CONFIG_PM_SLEEP
492static int um_suspend_valid(suspend_state_t state)
493{
494 return state == PM_SUSPEND_MEM;
495}
496
497static int um_suspend_prepare(void)
498{
499 um_irqs_suspend();
500 return 0;
501}
502
503static int um_suspend_enter(suspend_state_t state)
504{
505 if (WARN_ON(state != PM_SUSPEND_MEM))
506 return -EINVAL;
507
508 /*
509 * This is identical to the idle sleep, but we've just
510 * (during suspend) turned off all interrupt sources
511 * except for the ones we want, so now we can only wake
512 * up on something we actually want to wake up on. All
513 * timing has also been suspended.
514 */
515 um_idle_sleep();
516 return 0;
517}
518
519static void um_suspend_finish(void)
520{
521 um_irqs_resume();
522}
523
524const struct platform_suspend_ops um_suspend_ops = {
525 .valid = um_suspend_valid,
526 .prepare = um_suspend_prepare,
527 .enter = um_suspend_enter,
528 .finish = um_suspend_finish,
529};
530
531static int init_pm_wake_signal(void)
532{
533 /*
534 * In external time-travel mode we can't use signals to wake up
535 * since that would mess with the scheduling. We'll have to do
536 * some additional work to support wakeup on virtio devices or
537 * similar, perhaps implementing a fake RTC controller that can
538 * trigger wakeup (and request the appropriate scheduling from
539 * the external scheduler when going to suspend.)
540 */
541 if (time_travel_mode != TT_MODE_EXTERNAL)
542 register_pm_wake_signal();
543
544 suspend_set_ops(&um_suspend_ops);
545
546 return 0;
547}
548
549late_initcall(init_pm_wake_signal);
550#endif
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
251int __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 virtmem_size = physmem_size;
323 stack = (unsigned long) argv;
324 stack &= ~(1024 * 1024 - 1);
325 avail = stack - start_vm;
326 if (physmem_size > avail)
327 virtmem_size = avail;
328 end_vm = start_vm + virtmem_size;
329
330 if (virtmem_size < physmem_size)
331 printf("Kernel virtual memory size shrunk to %lu bytes\n",
332 virtmem_size);
333
334 os_flush_stdout();
335
336 return start_uml();
337}
338
339void __init setup_arch(char **cmdline_p)
340{
341 stack_protections((unsigned long) &init_thread_info);
342 setup_physmem(uml_physmem, uml_reserved, physmem_size, highmem);
343 mem_total_pages(physmem_size, iomem_size, highmem);
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
351void __init check_bugs(void)
352{
353 arch_check_bugs();
354 os_check_bugs();
355}
356
357void apply_alternatives(struct alt_instr *start, struct alt_instr *end)
358{
359}