123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341342343344345346347348349350351352353354355356357358359360361362363364365366367368369370371372373374375376377378379380381382383384385386387388389390391392393394395396397398399400401402403404405406407408409410411412413414415416417418419420421422423424425426427428429430431432433434435436437438439440441442443444445446447448449450451452453454455456457458459460461462463464465466467468469470471472473474475476477478479480481482483484485486487488489490491492493494495496497498499500501502503504505506507508509510511512513514515516517518519520521522523524525526527528529530531532 |
- // SPDX-License-Identifier: GPL-2.0
- /*
- * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
- */
- #include <linux/cpu.h>
- #include <linux/delay.h>
- #include <linux/init.h>
- #include <linux/mm.h>
- #include <linux/ctype.h>
- #include <linux/module.h>
- #include <linux/panic_notifier.h>
- #include <linux/seq_file.h>
- #include <linux/string.h>
- #include <linux/utsname.h>
- #include <linux/sched.h>
- #include <linux/sched/task.h>
- #include <linux/kmsg_dump.h>
- #include <linux/suspend.h>
- #include <linux/random.h>
- #include <asm/processor.h>
- #include <asm/cpufeature.h>
- #include <asm/sections.h>
- #include <asm/setup.h>
- #include <as-layout.h>
- #include <arch.h>
- #include <init.h>
- #include <kern.h>
- #include <kern_util.h>
- #include <mem_user.h>
- #include <os.h>
- #include "um_arch.h"
- #define DEFAULT_COMMAND_LINE_ROOT "root=98:0"
- #define DEFAULT_COMMAND_LINE_CONSOLE "console=tty0"
- /* Changed in add_arg and setup_arch, which run before SMP is started */
- static char __initdata command_line[COMMAND_LINE_SIZE] = { 0 };
- static void __init add_arg(char *arg)
- {
- if (strlen(command_line) + strlen(arg) + 1 > COMMAND_LINE_SIZE) {
- os_warn("add_arg: Too many command line arguments!\n");
- exit(1);
- }
- if (strlen(command_line) > 0)
- strcat(command_line, " ");
- strcat(command_line, arg);
- }
- /*
- * These fields are initialized at boot time and not changed.
- * XXX This structure is used only in the non-SMP case. Maybe this
- * should be moved to smp.c.
- */
- struct cpuinfo_um boot_cpu_data = {
- .loops_per_jiffy = 0,
- .ipi_pipe = { -1, -1 },
- .cache_alignment = L1_CACHE_BYTES,
- .x86_capability = { 0 }
- };
- EXPORT_SYMBOL(boot_cpu_data);
- union thread_union cpu0_irqstack
- __section(".data..init_irqstack") =
- { .thread_info = INIT_THREAD_INFO(init_task) };
- /* Changed in setup_arch, which is called in early boot */
- static char host_info[(__NEW_UTS_LEN + 1) * 5];
- static int show_cpuinfo(struct seq_file *m, void *v)
- {
- int i = 0;
- seq_printf(m, "processor\t: %d\n", i);
- seq_printf(m, "vendor_id\t: User Mode Linux\n");
- seq_printf(m, "model name\t: UML\n");
- seq_printf(m, "mode\t\t: skas\n");
- seq_printf(m, "host\t\t: %s\n", host_info);
- seq_printf(m, "fpu\t\t: %s\n", cpu_has(&boot_cpu_data, X86_FEATURE_FPU) ? "yes" : "no");
- seq_printf(m, "flags\t\t:");
- for (i = 0; i < 32*NCAPINTS; i++)
- if (cpu_has(&boot_cpu_data, i) && (x86_cap_flags[i] != NULL))
- seq_printf(m, " %s", x86_cap_flags[i]);
- seq_printf(m, "\n");
- seq_printf(m, "cache_alignment\t: %d\n", boot_cpu_data.cache_alignment);
- seq_printf(m, "bogomips\t: %lu.%02lu\n",
- loops_per_jiffy/(500000/HZ),
- (loops_per_jiffy/(5000/HZ)) % 100);
- return 0;
- }
- static void *c_start(struct seq_file *m, loff_t *pos)
- {
- return *pos < nr_cpu_ids ? cpu_data + *pos : NULL;
- }
- static void *c_next(struct seq_file *m, void *v, loff_t *pos)
- {
- ++*pos;
- return c_start(m, pos);
- }
- static void c_stop(struct seq_file *m, void *v)
- {
- }
- const struct seq_operations cpuinfo_op = {
- .start = c_start,
- .next = c_next,
- .stop = c_stop,
- .show = show_cpuinfo,
- };
- /* Set in linux_main */
- unsigned long uml_physmem;
- EXPORT_SYMBOL(uml_physmem);
- unsigned long uml_reserved; /* Also modified in mem_init */
- unsigned long start_vm;
- unsigned long end_vm;
- /* Set in uml_ncpus_setup */
- int ncpus = 1;
- /* Set in early boot */
- static int have_root __initdata;
- static int have_console __initdata;
- /* Set in uml_mem_setup and modified in linux_main */
- long long physmem_size = 64 * 1024 * 1024;
- EXPORT_SYMBOL(physmem_size);
- static const char *usage_string =
- "User Mode Linux v%s\n"
- " available at http://user-mode-linux.sourceforge.net/\n\n";
- static int __init uml_version_setup(char *line, int *add)
- {
- /* Explicitly use printf() to show version in stdout */
- printf("%s\n", init_utsname()->release);
- exit(0);
- return 0;
- }
- __uml_setup("--version", uml_version_setup,
- "--version\n"
- " Prints the version number of the kernel.\n\n"
- );
- static int __init uml_root_setup(char *line, int *add)
- {
- have_root = 1;
- return 0;
- }
- __uml_setup("root=", uml_root_setup,
- "root=<file containing the root fs>\n"
- " This is actually used by the generic kernel in exactly the same\n"
- " way as in any other kernel. If you configure a number of block\n"
- " devices and want to boot off something other than ubd0, you \n"
- " would use something like:\n"
- " root=/dev/ubd5\n\n"
- );
- static int __init no_skas_debug_setup(char *line, int *add)
- {
- os_warn("'debug' is not necessary to gdb UML in skas mode - run\n");
- os_warn("'gdb linux'\n");
- return 0;
- }
- __uml_setup("debug", no_skas_debug_setup,
- "debug\n"
- " this flag is not needed to run gdb on UML in skas mode\n\n"
- );
- static int __init uml_console_setup(char *line, int *add)
- {
- have_console = 1;
- return 0;
- }
- __uml_setup("console=", uml_console_setup,
- "console=<preferred console>\n"
- " Specify the preferred console output driver\n\n"
- );
- static int __init Usage(char *line, int *add)
- {
- const char **p;
- printf(usage_string, init_utsname()->release);
- p = &__uml_help_start;
- /* Explicitly use printf() to show help in stdout */
- while (p < &__uml_help_end) {
- printf("%s", *p);
- p++;
- }
- exit(0);
- return 0;
- }
- __uml_setup("--help", Usage,
- "--help\n"
- " Prints this message.\n\n"
- );
- static void __init uml_checksetup(char *line, int *add)
- {
- struct uml_param *p;
- p = &__uml_setup_start;
- while (p < &__uml_setup_end) {
- size_t n;
- n = strlen(p->str);
- if (!strncmp(line, p->str, n) && p->setup_func(line + n, add))
- return;
- p++;
- }
- }
- static void __init uml_postsetup(void)
- {
- initcall_t *p;
- p = &__uml_postsetup_start;
- while (p < &__uml_postsetup_end) {
- (*p)();
- p++;
- }
- return;
- }
- static int panic_exit(struct notifier_block *self, unsigned long unused1,
- void *unused2)
- {
- kmsg_dump(KMSG_DUMP_PANIC);
- bust_spinlocks(1);
- bust_spinlocks(0);
- uml_exitcode = 1;
- os_dump_core();
- return NOTIFY_DONE;
- }
- static struct notifier_block panic_exit_notifier = {
- .notifier_call = panic_exit,
- .priority = INT_MAX - 1, /* run as 2nd notifier, won't return */
- };
- void uml_finishsetup(void)
- {
- atomic_notifier_chain_register(&panic_notifier_list,
- &panic_exit_notifier);
- uml_postsetup();
- new_thread_handler();
- }
- /* Set during early boot */
- unsigned long stub_start;
- unsigned long task_size;
- EXPORT_SYMBOL(task_size);
- unsigned long host_task_size;
- unsigned long brk_start;
- unsigned long end_iomem;
- EXPORT_SYMBOL(end_iomem);
- #define MIN_VMALLOC (32 * 1024 * 1024)
- static void parse_host_cpu_flags(char *line)
- {
- int i;
- for (i = 0; i < 32*NCAPINTS; i++) {
- if ((x86_cap_flags[i] != NULL) && strstr(line, x86_cap_flags[i]))
- set_cpu_cap(&boot_cpu_data, i);
- }
- }
- static void parse_cache_line(char *line)
- {
- long res;
- char *to_parse = strstr(line, ":");
- if (to_parse) {
- to_parse++;
- while (*to_parse != 0 && isspace(*to_parse)) {
- to_parse++;
- }
- if (kstrtoul(to_parse, 10, &res) == 0 && is_power_of_2(res))
- boot_cpu_data.cache_alignment = res;
- else
- boot_cpu_data.cache_alignment = L1_CACHE_BYTES;
- }
- }
- int __init linux_main(int argc, char **argv)
- {
- unsigned long avail, diff;
- unsigned long virtmem_size, max_physmem;
- unsigned long stack;
- unsigned int i;
- int add;
- for (i = 1; i < argc; i++) {
- if ((i == 1) && (argv[i][0] == ' '))
- continue;
- add = 1;
- uml_checksetup(argv[i], &add);
- if (add)
- add_arg(argv[i]);
- }
- if (have_root == 0)
- add_arg(DEFAULT_COMMAND_LINE_ROOT);
- if (have_console == 0)
- add_arg(DEFAULT_COMMAND_LINE_CONSOLE);
- host_task_size = os_get_top_address();
- /* reserve two pages for the stubs */
- host_task_size -= 2 * PAGE_SIZE;
- stub_start = host_task_size;
- /*
- * TASK_SIZE needs to be PGDIR_SIZE aligned or else exit_mmap craps
- * out
- */
- task_size = host_task_size & PGDIR_MASK;
- /* OS sanity checks that need to happen before the kernel runs */
- os_early_checks();
- get_host_cpu_features(parse_host_cpu_flags, parse_cache_line);
- brk_start = (unsigned long) sbrk(0);
- /*
- * Increase physical memory size for exec-shield users
- * so they actually get what they asked for. This should
- * add zero for non-exec shield users
- */
- diff = UML_ROUND_UP(brk_start) - UML_ROUND_UP(&_end);
- if (diff > 1024 * 1024) {
- os_info("Adding %ld bytes to physical memory to account for "
- "exec-shield gap\n", diff);
- physmem_size += UML_ROUND_UP(brk_start) - UML_ROUND_UP(&_end);
- }
- uml_physmem = (unsigned long) __binary_start & PAGE_MASK;
- /* Reserve up to 4M after the current brk */
- uml_reserved = ROUND_4M(brk_start) + (1 << 22);
- setup_machinename(init_utsname()->machine);
- highmem = 0;
- iomem_size = (iomem_size + PAGE_SIZE - 1) & PAGE_MASK;
- max_physmem = TASK_SIZE - uml_physmem - iomem_size - MIN_VMALLOC;
- /*
- * Zones have to begin on a 1 << MAX_ORDER page boundary,
- * so this makes sure that's true for highmem
- */
- max_physmem &= ~((1 << (PAGE_SHIFT + MAX_ORDER)) - 1);
- if (physmem_size + iomem_size > max_physmem) {
- highmem = physmem_size + iomem_size - max_physmem;
- physmem_size -= highmem;
- }
- high_physmem = uml_physmem + physmem_size;
- end_iomem = high_physmem + iomem_size;
- high_memory = (void *) end_iomem;
- start_vm = VMALLOC_START;
- virtmem_size = physmem_size;
- stack = (unsigned long) argv;
- stack &= ~(1024 * 1024 - 1);
- avail = stack - start_vm;
- if (physmem_size > avail)
- virtmem_size = avail;
- end_vm = start_vm + virtmem_size;
- if (virtmem_size < physmem_size)
- os_info("Kernel virtual memory size shrunk to %lu bytes\n",
- virtmem_size);
- os_flush_stdout();
- return start_uml();
- }
- int __init __weak read_initrd(void)
- {
- return 0;
- }
- void __init setup_arch(char **cmdline_p)
- {
- u8 rng_seed[32];
- stack_protections((unsigned long) &init_thread_info);
- setup_physmem(uml_physmem, uml_reserved, physmem_size, highmem);
- mem_total_pages(physmem_size, iomem_size, highmem);
- uml_dtb_init();
- read_initrd();
- paging_init();
- strscpy(boot_command_line, command_line, COMMAND_LINE_SIZE);
- *cmdline_p = command_line;
- setup_hostinfo(host_info, sizeof host_info);
- if (os_getrandom(rng_seed, sizeof(rng_seed), 0) == sizeof(rng_seed)) {
- add_bootloader_randomness(rng_seed, sizeof(rng_seed));
- memzero_explicit(rng_seed, sizeof(rng_seed));
- }
- }
- void __init arch_cpu_finalize_init(void)
- {
- arch_check_bugs();
- os_check_bugs();
- }
- void apply_ibt_endbr(s32 *start, s32 *end)
- {
- }
- void apply_retpolines(s32 *start, s32 *end)
- {
- }
- void apply_returns(s32 *start, s32 *end)
- {
- }
- void apply_alternatives(struct alt_instr *start, struct alt_instr *end)
- {
- }
- void *text_poke(void *addr, const void *opcode, size_t len)
- {
- /*
- * In UML, the only reference to this function is in
- * apply_relocate_add(), which shouldn't ever actually call this
- * because UML doesn't have live patching.
- */
- WARN_ON(1);
- return memcpy(addr, opcode, len);
- }
- void text_poke_sync(void)
- {
- }
- void uml_pm_wake(void)
- {
- pm_system_wakeup();
- }
- #ifdef CONFIG_PM_SLEEP
- static int um_suspend_valid(suspend_state_t state)
- {
- return state == PM_SUSPEND_MEM;
- }
- static int um_suspend_prepare(void)
- {
- um_irqs_suspend();
- return 0;
- }
- static int um_suspend_enter(suspend_state_t state)
- {
- if (WARN_ON(state != PM_SUSPEND_MEM))
- return -EINVAL;
- /*
- * This is identical to the idle sleep, but we've just
- * (during suspend) turned off all interrupt sources
- * except for the ones we want, so now we can only wake
- * up on something we actually want to wake up on. All
- * timing has also been suspended.
- */
- um_idle_sleep();
- return 0;
- }
- static void um_suspend_finish(void)
- {
- um_irqs_resume();
- }
- const struct platform_suspend_ops um_suspend_ops = {
- .valid = um_suspend_valid,
- .prepare = um_suspend_prepare,
- .enter = um_suspend_enter,
- .finish = um_suspend_finish,
- };
- static int init_pm_wake_signal(void)
- {
- /*
- * In external time-travel mode we can't use signals to wake up
- * since that would mess with the scheduling. We'll have to do
- * some additional work to support wakeup on virtio devices or
- * similar, perhaps implementing a fake RTC controller that can
- * trigger wakeup (and request the appropriate scheduling from
- * the external scheduler when going to suspend.)
- */
- if (time_travel_mode != TT_MODE_EXTERNAL)
- register_pm_wake_signal();
- suspend_set_ops(&um_suspend_ops);
- return 0;
- }
- late_initcall(init_pm_wake_signal);
- #endif
|