linux/arch/um/kernel/main.c
Linus Torvalds 1da177e4c3 Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00

272 lines
6.0 KiB
C

/*
* Copyright (C) 2000, 2001 Jeff Dike (jdike@karaya.com)
* Licensed under the GPL
*/
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <signal.h>
#include <errno.h>
#include <sys/resource.h>
#include <sys/mman.h>
#include <sys/user.h>
#include <asm/page.h>
#include "user_util.h"
#include "kern_util.h"
#include "mem_user.h"
#include "signal_user.h"
#include "time_user.h"
#include "irq_user.h"
#include "user.h"
#include "init.h"
#include "mode.h"
#include "choose-mode.h"
#include "uml-config.h"
#include "irq_user.h"
#include "time_user.h"
#include "os.h"
/* Set in set_stklim, which is called from main and __wrap_malloc.
* __wrap_malloc only calls it if main hasn't started.
*/
unsigned long stacksizelim;
/* Set in main */
char *linux_prog;
#define PGD_BOUND (4 * 1024 * 1024)
#define STACKSIZE (8 * 1024 * 1024)
#define THREAD_NAME_LEN (256)
static void set_stklim(void)
{
struct rlimit lim;
if(getrlimit(RLIMIT_STACK, &lim) < 0){
perror("getrlimit");
exit(1);
}
if((lim.rlim_cur == RLIM_INFINITY) || (lim.rlim_cur > STACKSIZE)){
lim.rlim_cur = STACKSIZE;
if(setrlimit(RLIMIT_STACK, &lim) < 0){
perror("setrlimit");
exit(1);
}
}
stacksizelim = (lim.rlim_cur + PGD_BOUND - 1) & ~(PGD_BOUND - 1);
}
static __init void do_uml_initcalls(void)
{
initcall_t *call;
call = &__uml_initcall_start;
while (call < &__uml_initcall_end){;
(*call)();
call++;
}
}
static void last_ditch_exit(int sig)
{
CHOOSE_MODE(kmalloc_ok = 0, (void) 0);
signal(SIGINT, SIG_DFL);
signal(SIGTERM, SIG_DFL);
signal(SIGHUP, SIG_DFL);
uml_cleanup();
exit(1);
}
extern int uml_exitcode;
extern void scan_elf_aux( char **envp);
int main(int argc, char **argv, char **envp)
{
char **new_argv;
sigset_t mask;
int ret, i;
/* Enable all signals except SIGIO - in some environments, we can
* enter with some signals blocked
*/
sigemptyset(&mask);
sigaddset(&mask, SIGIO);
if(sigprocmask(SIG_SETMASK, &mask, NULL) < 0){
perror("sigprocmask");
exit(1);
}
#ifdef UML_CONFIG_MODE_TT
/* Allocate memory for thread command lines */
if(argc < 2 || strlen(argv[1]) < THREAD_NAME_LEN - 1){
char padding[THREAD_NAME_LEN] = {
[ 0 ... THREAD_NAME_LEN - 2] = ' ', '\0'
};
new_argv = malloc((argc + 2) * sizeof(char*));
if(!new_argv) {
perror("Allocating extended argv");
exit(1);
}
new_argv[0] = argv[0];
new_argv[1] = padding;
for(i = 2; i <= argc; i++)
new_argv[i] = argv[i - 1];
new_argv[argc + 1] = NULL;
execvp(new_argv[0], new_argv);
perror("execing with extended args");
exit(1);
}
#endif
linux_prog = argv[0];
set_stklim();
new_argv = malloc((argc + 1) * sizeof(char *));
if(new_argv == NULL){
perror("Mallocing argv");
exit(1);
}
for(i=0;i<argc;i++){
new_argv[i] = strdup(argv[i]);
if(new_argv[i] == NULL){
perror("Mallocing an arg");
exit(1);
}
}
new_argv[argc] = NULL;
set_handler(SIGINT, last_ditch_exit, SA_ONESHOT | SA_NODEFER, -1);
set_handler(SIGTERM, last_ditch_exit, SA_ONESHOT | SA_NODEFER, -1);
set_handler(SIGHUP, last_ditch_exit, SA_ONESHOT | SA_NODEFER, -1);
scan_elf_aux( envp);
do_uml_initcalls();
ret = linux_main(argc, argv);
/* Disable SIGPROF - I have no idea why libc doesn't do this or turn
* off the profiling time, but UML dies with a SIGPROF just before
* exiting when profiling is active.
*/
change_sig(SIGPROF, 0);
/* Reboot */
if(ret){
int err;
printf("\n");
/* stop timers and set SIG*ALRM to be ignored */
disable_timer();
/* disable SIGIO for the fds and set SIGIO to be ignored */
err = deactivate_all_fds();
if(err)
printf("deactivate_all_fds failed, errno = %d\n",
-err);
/* Let any pending signals fire now. This ensures
* that they won't be delivered after the exec, when
* they are definitely not expected.
*/
unblock_signals();
execvp(new_argv[0], new_argv);
perror("Failed to exec kernel");
ret = 1;
}
printf("\n");
return(uml_exitcode);
}
#define CAN_KMALLOC() \
(kmalloc_ok && CHOOSE_MODE((os_getpid() != tracing_pid), 1))
extern void *__real_malloc(int);
void *__wrap_malloc(int size)
{
void *ret;
if(!CAN_KMALLOC())
return(__real_malloc(size));
else if(size <= PAGE_SIZE) /* finding contiguos pages can be hard*/
ret = um_kmalloc(size);
else ret = um_vmalloc(size);
/* glibc people insist that if malloc fails, errno should be
* set by malloc as well. So we do.
*/
if(ret == NULL)
errno = ENOMEM;
return(ret);
}
void *__wrap_calloc(int n, int size)
{
void *ptr = __wrap_malloc(n * size);
if(ptr == NULL) return(NULL);
memset(ptr, 0, n * size);
return(ptr);
}
extern void __real_free(void *);
extern unsigned long high_physmem;
void __wrap_free(void *ptr)
{
unsigned long addr = (unsigned long) ptr;
/* We need to know how the allocation happened, so it can be correctly
* freed. This is done by seeing what region of memory the pointer is
* in -
* physical memory - kmalloc/kfree
* kernel virtual memory - vmalloc/vfree
* anywhere else - malloc/free
* If kmalloc is not yet possible, then either high_physmem and/or
* end_vm are still 0 (as at startup), in which case we call free, or
* we have set them, but anyway addr has not been allocated from those
* areas. So, in both cases __real_free is called.
*
* CAN_KMALLOC is checked because it would be bad to free a buffer
* with kmalloc/vmalloc after they have been turned off during
* shutdown.
* XXX: However, we sometimes shutdown CAN_KMALLOC temporarily, so
* there is a possibility for memory leaks.
*/
if((addr >= uml_physmem) && (addr < high_physmem)){
if(CAN_KMALLOC())
kfree(ptr);
}
else if((addr >= start_vm) && (addr < end_vm)){
if(CAN_KMALLOC())
vfree(ptr);
}
else __real_free(ptr);
}
/*
* Overrides for Emacs so that we follow Linus's tabbing style.
* Emacs will notice this stuff at the end of the file and automatically
* adjust the settings for this buffer only. This must remain at the end
* of the file.
* ---------------------------------------------------------------------------
* Local variables:
* c-file-style: "linux"
* End:
*/