2 * Copyright (C) 2000, 2001 Jeff Dike (jdike@karaya.com)
3 * Licensed under the GPL
12 #include <sys/resource.h>
15 #include "kern_util.h"
16 #include "as-layout.h"
22 #include "uml-config.h"
24 #include "um_malloc.h"
25 #include "kern_constants.h"
27 #define PGD_BOUND (4 * 1024 * 1024)
28 #define STACKSIZE (8 * 1024 * 1024)
29 #define THREAD_NAME_LEN (256)
31 static void set_stklim(void)
35 if(getrlimit(RLIMIT_STACK, &lim) < 0){
39 if((lim.rlim_cur == RLIM_INFINITY) || (lim.rlim_cur > STACKSIZE)){
40 lim.rlim_cur = STACKSIZE;
41 if(setrlimit(RLIMIT_STACK, &lim) < 0){
48 static __init void do_uml_initcalls(void)
52 call = &__uml_initcall_start;
53 while (call < &__uml_initcall_end){
59 static void last_ditch_exit(int sig)
65 static void install_fatal_handler(int sig)
67 struct sigaction action;
69 /* All signals are enabled in this handler ... */
70 sigemptyset(&action.sa_mask);
72 /* ... including the signal being handled, plus we want the
73 * handler reset to the default behavior, so that if an exit
74 * handler is hanging for some reason, the UML will just die
75 * after this signal is sent a second time.
77 action.sa_flags = SA_RESETHAND | SA_NODEFER;
78 action.sa_restorer = NULL;
79 action.sa_handler = last_ditch_exit;
80 if(sigaction(sig, &action, NULL) < 0){
81 printf("failed to install handler for signal %d - errno = %d\n",
87 #define UML_LIB_PATH ":/usr/lib/uml"
89 static void setup_env_path(void)
91 char *new_path = NULL;
92 char *old_path = NULL;
95 old_path = getenv("PATH");
96 /* if no PATH variable is set or it has an empty value
97 * just use the default + /usr/lib/uml
99 if (!old_path || (path_len = strlen(old_path)) == 0) {
100 putenv("PATH=:/bin:/usr/bin/" UML_LIB_PATH);
104 /* append /usr/lib/uml to the existing path */
105 path_len += strlen("PATH=" UML_LIB_PATH) + 1;
106 new_path = malloc(path_len);
108 perror("coudn't malloc to set a new PATH");
111 snprintf(new_path, path_len, "PATH=%s" UML_LIB_PATH, old_path);
115 extern int uml_exitcode;
117 extern void scan_elf_aux( char **envp);
119 int __init main(int argc, char **argv, char **envp)
128 new_argv = malloc((argc + 1) * sizeof(char *));
129 if(new_argv == NULL){
130 perror("Mallocing argv");
134 new_argv[i] = strdup(argv[i]);
135 if(new_argv[i] == NULL){
136 perror("Mallocing an arg");
140 new_argv[argc] = NULL;
142 /* Allow these signals to bring down a UML if all other
143 * methods of control fail.
145 install_fatal_handler(SIGINT);
146 install_fatal_handler(SIGTERM);
147 install_fatal_handler(SIGHUP);
152 ret = linux_main(argc, argv);
154 /* Disable SIGPROF - I have no idea why libc doesn't do this or turn
155 * off the profiling time, but UML dies with a SIGPROF just before
156 * exiting when profiling is active.
158 change_sig(SIGPROF, 0);
160 /* This signal stuff used to be in the reboot case. However,
161 * sometimes a SIGVTALRM can come in when we're halting (reproducably
162 * when writing out gcov information, presumably because that takes
163 * some time) and cause a segfault.
166 /* stop timers and set SIG*ALRM to be ignored */
169 /* disable SIGIO for the fds and set SIGIO to be ignored */
170 err = deactivate_all_fds();
172 printf("deactivate_all_fds failed, errno = %d\n", -err);
174 /* Let any pending signals fire now. This ensures
175 * that they won't be delivered after the exec, when
176 * they are definitely not expected.
183 execvp(new_argv[0], new_argv);
184 perror("Failed to exec kernel");
191 extern void *__real_malloc(int);
193 void *__wrap_malloc(int size)
198 return __real_malloc(size);
199 else if(size <= UM_KERN_PAGE_SIZE)
200 /* finding contiguous pages can be hard*/
201 ret = kmalloc(size, UM_GFP_KERNEL);
202 else ret = vmalloc(size);
204 /* glibc people insist that if malloc fails, errno should be
205 * set by malloc as well. So we do.
213 void *__wrap_calloc(int n, int size)
215 void *ptr = __wrap_malloc(n * size);
219 memset(ptr, 0, n * size);
223 extern void __real_free(void *);
225 extern unsigned long high_physmem;
227 void __wrap_free(void *ptr)
229 unsigned long addr = (unsigned long) ptr;
231 /* We need to know how the allocation happened, so it can be correctly
232 * freed. This is done by seeing what region of memory the pointer is
234 * physical memory - kmalloc/kfree
235 * kernel virtual memory - vmalloc/vfree
236 * anywhere else - malloc/free
237 * If kmalloc is not yet possible, then either high_physmem and/or
238 * end_vm are still 0 (as at startup), in which case we call free, or
239 * we have set them, but anyway addr has not been allocated from those
240 * areas. So, in both cases __real_free is called.
242 * CAN_KMALLOC is checked because it would be bad to free a buffer
243 * with kmalloc/vmalloc after they have been turned off during
245 * XXX: However, we sometimes shutdown CAN_KMALLOC temporarily, so
246 * there is a possibility for memory leaks.
249 if((addr >= uml_physmem) && (addr < high_physmem)){
253 else if((addr >= start_vm) && (addr < end_vm)){
257 else __real_free(ptr);