| /* |
| * 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 "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) |
| { |
| uml_cleanup(); |
| exit(1); |
| } |
| |
| static void install_fatal_handler(int sig) |
| { |
| struct sigaction action; |
| |
| /* All signals are enabled in this handler ... */ |
| sigemptyset(&action.sa_mask); |
| |
| /* ... including the signal being handled, plus we want the |
| * handler reset to the default behavior, so that if an exit |
| * handler is hanging for some reason, the UML will just die |
| * after this signal is sent a second time. |
| */ |
| action.sa_flags = SA_RESETHAND | SA_NODEFER; |
| action.sa_restorer = NULL; |
| action.sa_handler = last_ditch_exit; |
| if(sigaction(sig, &action, NULL) < 0){ |
| printf("failed to install handler for signal %d - errno = %d\n", |
| errno); |
| exit(1); |
| } |
| } |
| |
| #define UML_LIB_PATH ":/usr/lib/uml" |
| |
| static void setup_env_path(void) |
| { |
| char *new_path = NULL; |
| char *old_path = NULL; |
| int path_len = 0; |
| |
| old_path = getenv("PATH"); |
| /* if no PATH variable is set or it has an empty value |
| * just use the default + /usr/lib/uml |
| */ |
| if (!old_path || (path_len = strlen(old_path)) == 0) { |
| putenv("PATH=:/bin:/usr/bin/" UML_LIB_PATH); |
| return; |
| } |
| |
| /* append /usr/lib/uml to the existing path */ |
| path_len += strlen("PATH=" UML_LIB_PATH) + 1; |
| new_path = malloc(path_len); |
| if (!new_path) { |
| perror("coudn't malloc to set a new PATH"); |
| return; |
| } |
| snprintf(new_path, path_len, "PATH=%s" UML_LIB_PATH, old_path); |
| putenv(new_path); |
| } |
| |
| extern int uml_exitcode; |
| |
| extern void scan_elf_aux( char **envp); |
| |
| int main(int argc, char **argv, char **envp) |
| { |
| char **new_argv; |
| int ret, i, err; |
| |
| #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(); |
| |
| setup_env_path(); |
| |
| 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; |
| |
| /* Allow these signals to bring down a UML if all other |
| * methods of control fail. |
| */ |
| install_fatal_handler(SIGINT); |
| install_fatal_handler(SIGTERM); |
| install_fatal_handler(SIGHUP); |
| |
| 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); |
| } |