summary refs log tree commit diff
path: root/arch/um/kernel/um_arch.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/um/kernel/um_arch.c')
-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 000000000000..5c49d88eed3d
--- /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)
+{
+}