| // SPDX-License-Identifier: GPL-2.0 |
| /* |
| * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com) |
| */ |
| |
| #include <linux/delay.h> |
| #include <linux/init.h> |
| #include <linux/mm.h> |
| #include <linux/module.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 <asm/processor.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> |
| |
| #define DEFAULT_COMMAND_LINE "root=98:0" |
| |
| /* 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 } |
| }; |
| |
| 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 index = 0; |
| |
| seq_printf(m, "processor\t: %d\n", index); |
| 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, "bogomips\t: %lu.%02lu\n\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_CPUS ? 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 = 0; |
| |
| /* Set in uml_mem_setup and modified in linux_main */ |
| long long physmem_size = 32 * 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 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 0; |
| } |
| |
| static struct notifier_block panic_exit_notifier = { |
| .notifier_call = panic_exit, |
| .next = NULL, |
| .priority = 0 |
| }; |
| |
| 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 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) |
| |
| 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); |
| |
| host_task_size = os_get_top_address(); |
| /* |
| * 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(); |
| |
| 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) |
| { |
| stack_protections((unsigned long) &init_thread_info); |
| setup_physmem(uml_physmem, uml_reserved, physmem_size, highmem); |
| mem_total_pages(physmem_size, iomem_size, highmem); |
| read_initrd(); |
| |
| paging_init(); |
| strlcpy(boot_command_line, command_line, COMMAND_LINE_SIZE); |
| *cmdline_p = command_line; |
| setup_hostinfo(host_info, sizeof host_info); |
| } |
| |
| void __init check_bugs(void) |
| { |
| arch_check_bugs(); |
| os_check_bugs(); |
| } |
| |
| 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 |