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Commit | Line | Data |
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1da177e4 | 1 | /* |
ba180fd4 | 2 | * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com) |
1da177e4 LT |
3 | * Licensed under the GPL |
4 | */ | |
5 | ||
1da177e4 LT |
6 | #include <stdio.h> |
7 | #include <stdlib.h> | |
ba180fd4 | 8 | #include <unistd.h> |
1da177e4 | 9 | #include <errno.h> |
ba180fd4 JD |
10 | #include <signal.h> |
11 | #include <string.h> | |
1da177e4 | 12 | #include <sys/resource.h> |
37185b33 AV |
13 | #include <as-layout.h> |
14 | #include <init.h> | |
15 | #include <kern_util.h> | |
16 | #include <os.h> | |
17 | #include <um_malloc.h> | |
1da177e4 | 18 | |
1da177e4 LT |
19 | #define PGD_BOUND (4 * 1024 * 1024) |
20 | #define STACKSIZE (8 * 1024 * 1024) | |
21 | #define THREAD_NAME_LEN (256) | |
22 | ||
b743ac54 RW |
23 | long elf_aux_hwcap; |
24 | ||
1da177e4 LT |
25 | static void set_stklim(void) |
26 | { | |
27 | struct rlimit lim; | |
28 | ||
ba180fd4 | 29 | if (getrlimit(RLIMIT_STACK, &lim) < 0) { |
1da177e4 LT |
30 | perror("getrlimit"); |
31 | exit(1); | |
32 | } | |
ba180fd4 | 33 | if ((lim.rlim_cur == RLIM_INFINITY) || (lim.rlim_cur > STACKSIZE)) { |
1da177e4 | 34 | lim.rlim_cur = STACKSIZE; |
ba180fd4 | 35 | if (setrlimit(RLIMIT_STACK, &lim) < 0) { |
1da177e4 LT |
36 | perror("setrlimit"); |
37 | exit(1); | |
38 | } | |
39 | } | |
1da177e4 LT |
40 | } |
41 | ||
42 | static __init void do_uml_initcalls(void) | |
43 | { | |
44 | initcall_t *call; | |
45 | ||
46 | call = &__uml_initcall_start; | |
ba180fd4 | 47 | while (call < &__uml_initcall_end) { |
1da177e4 LT |
48 | (*call)(); |
49 | call++; | |
50 | } | |
51 | } | |
52 | ||
53 | static void last_ditch_exit(int sig) | |
54 | { | |
1da177e4 LT |
55 | uml_cleanup(); |
56 | exit(1); | |
57 | } | |
58 | ||
4b84c69b JD |
59 | static void install_fatal_handler(int sig) |
60 | { | |
61 | struct sigaction action; | |
62 | ||
63 | /* All signals are enabled in this handler ... */ | |
64 | sigemptyset(&action.sa_mask); | |
65 | ||
ba180fd4 JD |
66 | /* |
67 | * ... including the signal being handled, plus we want the | |
4b84c69b JD |
68 | * handler reset to the default behavior, so that if an exit |
69 | * handler is hanging for some reason, the UML will just die | |
70 | * after this signal is sent a second time. | |
71 | */ | |
72 | action.sa_flags = SA_RESETHAND | SA_NODEFER; | |
73 | action.sa_restorer = NULL; | |
74 | action.sa_handler = last_ditch_exit; | |
ba180fd4 | 75 | if (sigaction(sig, &action, NULL) < 0) { |
4b84c69b | 76 | printf("failed to install handler for signal %d - errno = %d\n", |
c9a3072d | 77 | sig, errno); |
4b84c69b JD |
78 | exit(1); |
79 | } | |
80 | } | |
81 | ||
0ce451ac | 82 | #define UML_LIB_PATH ":" OS_LIB_PATH "/uml" |
cb98cdcd MD |
83 | |
84 | static void setup_env_path(void) | |
85 | { | |
86 | char *new_path = NULL; | |
87 | char *old_path = NULL; | |
88 | int path_len = 0; | |
89 | ||
90 | old_path = getenv("PATH"); | |
ba180fd4 JD |
91 | /* |
92 | * if no PATH variable is set or it has an empty value | |
cb98cdcd MD |
93 | * just use the default + /usr/lib/uml |
94 | */ | |
95 | if (!old_path || (path_len = strlen(old_path)) == 0) { | |
c9a3072d WC |
96 | if (putenv("PATH=:/bin:/usr/bin/" UML_LIB_PATH)) |
97 | perror("couldn't putenv"); | |
cb98cdcd MD |
98 | return; |
99 | } | |
100 | ||
101 | /* append /usr/lib/uml to the existing path */ | |
102 | path_len += strlen("PATH=" UML_LIB_PATH) + 1; | |
103 | new_path = malloc(path_len); | |
104 | if (!new_path) { | |
c9a3072d | 105 | perror("couldn't malloc to set a new PATH"); |
cb98cdcd MD |
106 | return; |
107 | } | |
108 | snprintf(new_path, path_len, "PATH=%s" UML_LIB_PATH, old_path); | |
c9a3072d WC |
109 | if (putenv(new_path)) { |
110 | perror("couldn't putenv to set a new PATH"); | |
111 | free(new_path); | |
112 | } | |
cb98cdcd MD |
113 | } |
114 | ||
1da177e4 LT |
115 | extern void scan_elf_aux( char **envp); |
116 | ||
36e45463 | 117 | int __init main(int argc, char **argv, char **envp) |
1da177e4 LT |
118 | { |
119 | char **new_argv; | |
92515da7 | 120 | int ret, i, err; |
1da177e4 | 121 | |
1da177e4 LT |
122 | set_stklim(); |
123 | ||
cb98cdcd MD |
124 | setup_env_path(); |
125 | ||
25012721 RW |
126 | setsid(); |
127 | ||
1da177e4 | 128 | new_argv = malloc((argc + 1) * sizeof(char *)); |
ba180fd4 | 129 | if (new_argv == NULL) { |
1da177e4 LT |
130 | perror("Mallocing argv"); |
131 | exit(1); | |
132 | } | |
ba180fd4 | 133 | for (i = 0; i < argc; i++) { |
1da177e4 | 134 | new_argv[i] = strdup(argv[i]); |
ba180fd4 | 135 | if (new_argv[i] == NULL) { |
1da177e4 LT |
136 | perror("Mallocing an arg"); |
137 | exit(1); | |
138 | } | |
139 | } | |
140 | new_argv[argc] = NULL; | |
141 | ||
ba180fd4 JD |
142 | /* |
143 | * Allow these signals to bring down a UML if all other | |
4b84c69b JD |
144 | * methods of control fail. |
145 | */ | |
146 | install_fatal_handler(SIGINT); | |
147 | install_fatal_handler(SIGTERM); | |
1da177e4 | 148 | |
b743ac54 | 149 | #ifdef CONFIG_ARCH_REUSE_HOST_VSYSCALL_AREA |
ba180fd4 | 150 | scan_elf_aux(envp); |
b743ac54 | 151 | #endif |
1da177e4 LT |
152 | |
153 | do_uml_initcalls(); | |
154 | ret = linux_main(argc, argv); | |
155 | ||
ba180fd4 JD |
156 | /* |
157 | * Disable SIGPROF - I have no idea why libc doesn't do this or turn | |
1da177e4 LT |
158 | * off the profiling time, but UML dies with a SIGPROF just before |
159 | * exiting when profiling is active. | |
160 | */ | |
161 | change_sig(SIGPROF, 0); | |
162 | ||
ba180fd4 JD |
163 | /* |
164 | * This signal stuff used to be in the reboot case. However, | |
52c653b3 JD |
165 | * sometimes a SIGVTALRM can come in when we're halting (reproducably |
166 | * when writing out gcov information, presumably because that takes | |
167 | * some time) and cause a segfault. | |
168 | */ | |
169 | ||
61b63c55 | 170 | /* stop timers and set SIGVTALRM to be ignored */ |
52c653b3 JD |
171 | disable_timer(); |
172 | ||
173 | /* disable SIGIO for the fds and set SIGIO to be ignored */ | |
174 | err = deactivate_all_fds(); | |
ba180fd4 | 175 | if (err) |
52c653b3 JD |
176 | printf("deactivate_all_fds failed, errno = %d\n", -err); |
177 | ||
ba180fd4 JD |
178 | /* |
179 | * Let any pending signals fire now. This ensures | |
52c653b3 JD |
180 | * that they won't be delivered after the exec, when |
181 | * they are definitely not expected. | |
182 | */ | |
183 | unblock_signals(); | |
1da177e4 | 184 | |
92515da7 | 185 | /* Reboot */ |
ba180fd4 | 186 | if (ret) { |
92515da7 | 187 | printf("\n"); |
1da177e4 LT |
188 | execvp(new_argv[0], new_argv); |
189 | perror("Failed to exec kernel"); | |
190 | ret = 1; | |
191 | } | |
192 | printf("\n"); | |
a5ed1ffa | 193 | return uml_exitcode; |
1da177e4 LT |
194 | } |
195 | ||
1da177e4 LT |
196 | extern void *__real_malloc(int); |
197 | ||
198 | void *__wrap_malloc(int size) | |
199 | { | |
200 | void *ret; | |
201 | ||
ba180fd4 | 202 | if (!kmalloc_ok) |
a5ed1ffa | 203 | return __real_malloc(size); |
ba180fd4 | 204 | else if (size <= UM_KERN_PAGE_SIZE) |
c539ab73 | 205 | /* finding contiguous pages can be hard*/ |
43f5b308 | 206 | ret = uml_kmalloc(size, UM_GFP_KERNEL); |
e4c4bf99 | 207 | else ret = vmalloc(size); |
1da177e4 | 208 | |
ba180fd4 JD |
209 | /* |
210 | * glibc people insist that if malloc fails, errno should be | |
1da177e4 LT |
211 | * set by malloc as well. So we do. |
212 | */ | |
ba180fd4 | 213 | if (ret == NULL) |
1da177e4 LT |
214 | errno = ENOMEM; |
215 | ||
a5ed1ffa | 216 | return ret; |
1da177e4 LT |
217 | } |
218 | ||
219 | void *__wrap_calloc(int n, int size) | |
220 | { | |
221 | void *ptr = __wrap_malloc(n * size); | |
222 | ||
ba180fd4 | 223 | if (ptr == NULL) |
a5ed1ffa | 224 | return NULL; |
1da177e4 | 225 | memset(ptr, 0, n * size); |
a5ed1ffa | 226 | return ptr; |
1da177e4 LT |
227 | } |
228 | ||
229 | extern void __real_free(void *); | |
230 | ||
231 | extern unsigned long high_physmem; | |
232 | ||
233 | void __wrap_free(void *ptr) | |
234 | { | |
235 | unsigned long addr = (unsigned long) ptr; | |
236 | ||
ba180fd4 JD |
237 | /* |
238 | * We need to know how the allocation happened, so it can be correctly | |
1da177e4 LT |
239 | * freed. This is done by seeing what region of memory the pointer is |
240 | * in - | |
241 | * physical memory - kmalloc/kfree | |
242 | * kernel virtual memory - vmalloc/vfree | |
243 | * anywhere else - malloc/free | |
244 | * If kmalloc is not yet possible, then either high_physmem and/or | |
245 | * end_vm are still 0 (as at startup), in which case we call free, or | |
246 | * we have set them, but anyway addr has not been allocated from those | |
247 | * areas. So, in both cases __real_free is called. | |
248 | * | |
249 | * CAN_KMALLOC is checked because it would be bad to free a buffer | |
250 | * with kmalloc/vmalloc after they have been turned off during | |
251 | * shutdown. | |
252 | * XXX: However, we sometimes shutdown CAN_KMALLOC temporarily, so | |
253 | * there is a possibility for memory leaks. | |
254 | */ | |
255 | ||
ba180fd4 JD |
256 | if ((addr >= uml_physmem) && (addr < high_physmem)) { |
257 | if (kmalloc_ok) | |
1da177e4 LT |
258 | kfree(ptr); |
259 | } | |
ba180fd4 JD |
260 | else if ((addr >= start_vm) && (addr < end_vm)) { |
261 | if (kmalloc_ok) | |
1da177e4 LT |
262 | vfree(ptr); |
263 | } | |
264 | else __real_free(ptr); | |
265 | } |