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-rw-r--r--arch/um/os-Linux/main.c259
1 files changed, 259 insertions, 0 deletions
diff --git a/arch/um/os-Linux/main.c b/arch/um/os-Linux/main.c
new file mode 100644
index 00000000000..23da27d2256
--- /dev/null
+++ b/arch/um/os-Linux/main.c
@@ -0,0 +1,259 @@
+/*
+ * 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 "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)
+{
+ 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, err;
+
+ /* 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_CMDLINE_ON_HOST
+ /* 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);
+
+ /* This signal stuff used to be in the reboot case. However,
+ * sometimes a SIGVTALRM can come in when we're halting (reproducably
+ * when writing out gcov information, presumably because that takes
+ * some time) and cause a segfault.
+ */
+
+ /* 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();
+
+ /* Reboot */
+ if(ret){
+ printf("\n");
+ 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);
+}