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-rw-r--r--arch/um/kernel/um_arch.c467
1 files changed, 467 insertions, 0 deletions
diff --git a/arch/um/kernel/um_arch.c b/arch/um/kernel/um_arch.c
new file mode 100644
index 00000000000..5c49d88eed3
--- /dev/null
+++ b/arch/um/kernel/um_arch.c
@@ -0,0 +1,467 @@
+/*
+ * Copyright (C) 2000, 2002 Jeff Dike (jdike@karaya.com)
+ * Licensed under the GPL
+ */
+
+#include "linux/config.h"
+#include "linux/kernel.h"
+#include "linux/sched.h"
+#include "linux/notifier.h"
+#include "linux/mm.h"
+#include "linux/types.h"
+#include "linux/tty.h"
+#include "linux/init.h"
+#include "linux/bootmem.h"
+#include "linux/spinlock.h"
+#include "linux/utsname.h"
+#include "linux/sysrq.h"
+#include "linux/seq_file.h"
+#include "linux/delay.h"
+#include "linux/module.h"
+#include "asm/page.h"
+#include "asm/pgtable.h"
+#include "asm/ptrace.h"
+#include "asm/elf.h"
+#include "asm/user.h"
+#include "ubd_user.h"
+#include "asm/current.h"
+#include "asm/setup.h"
+#include "user_util.h"
+#include "kern_util.h"
+#include "kern.h"
+#include "mem_user.h"
+#include "mem.h"
+#include "umid.h"
+#include "initrd.h"
+#include "init.h"
+#include "os.h"
+#include "choose-mode.h"
+#include "mode_kern.h"
+#include "mode.h"
+
+#define DEFAULT_COMMAND_LINE "root=98:0"
+
+/* Changed in linux_main and setup_arch, which run before SMP is started */
+char command_line[COMMAND_LINE_SIZE] = { 0 };
+
+void add_arg(char *arg)
+{
+ if (strlen(command_line) + strlen(arg) + 1 > COMMAND_LINE_SIZE) {
+ printf("add_arg: Too many command line arguments!\n");
+ exit(1);
+ }
+ if(strlen(command_line) > 0)
+ strcat(command_line, " ");
+ strcat(command_line, arg);
+}
+
+struct cpuinfo_um boot_cpu_data = {
+ .loops_per_jiffy = 0,
+ .ipi_pipe = { -1, -1 }
+};
+
+unsigned long thread_saved_pc(struct task_struct *task)
+{
+ return(os_process_pc(CHOOSE_MODE_PROC(thread_pid_tt, thread_pid_skas,
+ task)));
+}
+
+static int show_cpuinfo(struct seq_file *m, void *v)
+{
+ int index = 0;
+
+#ifdef CONFIG_SMP
+ index = (struct cpuinfo_um *) v - cpu_data;
+ if (!cpu_online(index))
+ return 0;
+#endif
+
+ 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: %s\n", CHOOSE_MODE("tt", "skas"));
+ 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)
+{
+}
+
+struct seq_operations cpuinfo_op = {
+ .start = c_start,
+ .next = c_next,
+ .stop = c_stop,
+ .show = show_cpuinfo,
+};
+
+pte_t * __bad_pagetable(void)
+{
+ panic("Someone should implement __bad_pagetable");
+ return(NULL);
+}
+
+/* Set in linux_main */
+unsigned long host_task_size;
+unsigned long task_size;
+
+unsigned long uml_start;
+
+/* Set in early boot */
+unsigned long uml_physmem;
+unsigned long uml_reserved;
+unsigned long start_vm;
+unsigned long end_vm;
+int ncpus = 1;
+
+#ifdef CONFIG_MODE_TT
+/* Pointer set in linux_main, the array itself is private to each thread,
+ * and changed at address space creation time so this poses no concurrency
+ * problems.
+ */
+static char *argv1_begin = NULL;
+static char *argv1_end = NULL;
+#endif
+
+/* Set in early boot */
+static int have_root __initdata = 0;
+long physmem_size = 32 * 1024 * 1024;
+
+void set_cmdline(char *cmd)
+{
+#ifdef CONFIG_MODE_TT
+ char *umid, *ptr;
+
+ if(CHOOSE_MODE(honeypot, 0)) return;
+
+ umid = get_umid(1);
+ if(umid != NULL){
+ snprintf(argv1_begin,
+ (argv1_end - argv1_begin) * sizeof(*ptr),
+ "(%s) ", umid);
+ ptr = &argv1_begin[strlen(argv1_begin)];
+ }
+ else ptr = argv1_begin;
+
+ snprintf(ptr, (argv1_end - ptr) * sizeof(*ptr), "[%s]", cmd);
+ memset(argv1_begin + strlen(argv1_begin), '\0',
+ argv1_end - argv1_begin - strlen(argv1_begin));
+#endif
+}
+
+static 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)
+{
+ printf("%s\n", system_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"
+);
+
+#ifdef CONFIG_SMP
+static int __init uml_ncpus_setup(char *line, int *add)
+{
+ if (!sscanf(line, "%d", &ncpus)) {
+ printf("Couldn't parse [%s]\n", line);
+ return -1;
+ }
+
+ return 0;
+}
+
+__uml_setup("ncpus=", uml_ncpus_setup,
+"ncpus=<# of desired CPUs>\n"
+" This tells an SMP kernel how many virtual processors to start.\n\n"
+);
+#endif
+
+static int force_tt = 0;
+
+#if defined(CONFIG_MODE_TT) && defined(CONFIG_MODE_SKAS)
+#define DEFAULT_TT 0
+
+static int __init mode_tt_setup(char *line, int *add)
+{
+ force_tt = 1;
+ return(0);
+}
+
+#else
+#ifdef CONFIG_MODE_SKAS
+
+#define DEFAULT_TT 0
+
+static int __init mode_tt_setup(char *line, int *add)
+{
+ printf("CONFIG_MODE_TT disabled - 'mode=tt' ignored\n");
+ return(0);
+}
+
+#else
+#ifdef CONFIG_MODE_TT
+
+#define DEFAULT_TT 1
+
+static int __init mode_tt_setup(char *line, int *add)
+{
+ printf("CONFIG_MODE_SKAS disabled - 'mode=tt' redundant\n");
+ return(0);
+}
+
+#else
+
+#error Either CONFIG_MODE_TT or CONFIG_MODE_SKAS must be enabled
+
+#endif
+#endif
+#endif
+
+__uml_setup("mode=tt", mode_tt_setup,
+"mode=tt\n"
+" When both CONFIG_MODE_TT and CONFIG_MODE_SKAS are enabled, this option\n"
+" forces UML to run in tt (tracing thread) mode. It is not the default\n"
+" because it's slower and less secure than skas mode.\n\n"
+);
+
+int mode_tt = DEFAULT_TT;
+
+static int __init Usage(char *line, int *add)
+{
+ const char **p;
+
+ printf(usage_string, system_utsname.release);
+ p = &__uml_help_start;
+ 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 int __init uml_checksetup(char *line, int *add)
+{
+ struct uml_param *p;
+
+ p = &__uml_setup_start;
+ while(p < &__uml_setup_end) {
+ int n;
+
+ n = strlen(p->str);
+ if(!strncmp(line, p->str, n)){
+ if (p->setup_func(line + n, add)) return 1;
+ }
+ p++;
+ }
+ return 0;
+}
+
+static void __init uml_postsetup(void)
+{
+ initcall_t *p;
+
+ p = &__uml_postsetup_start;
+ while(p < &__uml_postsetup_end){
+ (*p)();
+ p++;
+ }
+ return;
+}
+
+/* Set during early boot */
+unsigned long brk_start;
+unsigned long end_iomem;
+EXPORT_SYMBOL(end_iomem);
+
+#define MIN_VMALLOC (32 * 1024 * 1024)
+
+int linux_main(int argc, char **argv)
+{
+ unsigned long avail, diff;
+ unsigned long virtmem_size, max_physmem;
+ unsigned int i, 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);
+
+ mode_tt = force_tt ? 1 : !can_do_skas();
+#ifndef CONFIG_MODE_TT
+ if (mode_tt) {
+ /*Since CONFIG_MODE_TT is #undef'ed, force_tt cannot be 1. So,
+ * can_do_skas() returned 0, and the message is correct. */
+ printf("Support for TT mode is disabled, and no SKAS support is present on the host.\n");
+ exit(1);
+ }
+#endif
+ uml_start = CHOOSE_MODE_PROC(set_task_sizes_tt, set_task_sizes_skas, 0,
+ &host_task_size, &task_size);
+
+ /* Need to check this early because mmapping happens before the
+ * kernel is running.
+ */
+ check_tmpexec();
+
+ brk_start = (unsigned long) sbrk(0);
+ CHOOSE_MODE_PROC(before_mem_tt, before_mem_skas, brk_start);
+ /* 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){
+ printf("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 = uml_start;
+
+ /* Reserve up to 4M after the current brk */
+ uml_reserved = ROUND_4M(brk_start) + (1 << 22);
+
+ setup_machinename(system_utsname.machine);
+
+#ifdef CONFIG_MODE_TT
+ argv1_begin = argv[1];
+ argv1_end = &argv[1][strlen(argv[1])];
+#endif
+
+ highmem = 0;
+ iomem_size = (iomem_size + PAGE_SIZE - 1) & PAGE_MASK;
+ max_physmem = get_kmem_end() - 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;
+#ifndef CONFIG_HIGHMEM
+ highmem = 0;
+ printf("CONFIG_HIGHMEM not enabled - physical memory shrunk "
+ "to %ld bytes\n", physmem_size);
+#endif
+ }
+
+ high_physmem = uml_physmem + physmem_size;
+ end_iomem = high_physmem + iomem_size;
+ high_memory = (void *) end_iomem;
+
+ start_vm = VMALLOC_START;
+
+ setup_physmem(uml_physmem, uml_reserved, physmem_size, highmem);
+ if(init_maps(physmem_size, iomem_size, highmem)){
+ printf("Failed to allocate mem_map for %ld bytes of physical "
+ "memory and %ld bytes of highmem\n", physmem_size,
+ highmem);
+ exit(1);
+ }
+
+ virtmem_size = physmem_size;
+ avail = get_kmem_end() - start_vm;
+ if(physmem_size > avail) virtmem_size = avail;
+ end_vm = start_vm + virtmem_size;
+
+ if(virtmem_size < physmem_size)
+ printf("Kernel virtual memory size shrunk to %ld bytes\n",
+ virtmem_size);
+
+ uml_postsetup();
+
+ task_protections((unsigned long) &init_thread_info);
+ os_flush_stdout();
+
+ return(CHOOSE_MODE(start_uml_tt(), start_uml_skas()));
+}
+
+extern int uml_exitcode;
+
+static int panic_exit(struct notifier_block *self, unsigned long unused1,
+ void *unused2)
+{
+ bust_spinlocks(1);
+ show_regs(&(current->thread.regs));
+ bust_spinlocks(0);
+ uml_exitcode = 1;
+ machine_halt();
+ return(0);
+}
+
+static struct notifier_block panic_exit_notifier = {
+ .notifier_call = panic_exit,
+ .next = NULL,
+ .priority = 0
+};
+
+void __init setup_arch(char **cmdline_p)
+{
+ notifier_chain_register(&panic_notifier_list, &panic_exit_notifier);
+ paging_init();
+ strlcpy(saved_command_line, command_line, COMMAND_LINE_SIZE);
+ *cmdline_p = command_line;
+ setup_hostinfo();
+}
+
+void __init check_bugs(void)
+{
+ arch_check_bugs();
+ check_ptrace();
+ check_sigio();
+ check_devanon();
+}
+
+void apply_alternatives(void *start, void *end)
+{
+}