diff options
Diffstat (limited to 'arch/um/os-Linux/main.c')
-rw-r--r-- | arch/um/os-Linux/main.c | 259 |
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 000000000000..23da27d22569 --- /dev/null +++ b/arch/um/os-Linux/main.c | |||
@@ -0,0 +1,259 @@ | |||
1 | /* | ||
2 | * Copyright (C) 2000, 2001 Jeff Dike (jdike@karaya.com) | ||
3 | * Licensed under the GPL | ||
4 | */ | ||
5 | |||
6 | #include <unistd.h> | ||
7 | #include <stdio.h> | ||
8 | #include <stdlib.h> | ||
9 | #include <string.h> | ||
10 | #include <signal.h> | ||
11 | #include <errno.h> | ||
12 | #include <sys/resource.h> | ||
13 | #include <sys/mman.h> | ||
14 | #include <sys/user.h> | ||
15 | #include <asm/page.h> | ||
16 | #include "user_util.h" | ||
17 | #include "kern_util.h" | ||
18 | #include "mem_user.h" | ||
19 | #include "signal_user.h" | ||
20 | #include "time_user.h" | ||
21 | #include "irq_user.h" | ||
22 | #include "user.h" | ||
23 | #include "init.h" | ||
24 | #include "mode.h" | ||
25 | #include "choose-mode.h" | ||
26 | #include "uml-config.h" | ||
27 | #include "os.h" | ||
28 | |||
29 | /* Set in set_stklim, which is called from main and __wrap_malloc. | ||
30 | * __wrap_malloc only calls it if main hasn't started. | ||
31 | */ | ||
32 | unsigned long stacksizelim; | ||
33 | |||
34 | /* Set in main */ | ||
35 | char *linux_prog; | ||
36 | |||
37 | #define PGD_BOUND (4 * 1024 * 1024) | ||
38 | #define STACKSIZE (8 * 1024 * 1024) | ||
39 | #define THREAD_NAME_LEN (256) | ||
40 | |||
41 | static void set_stklim(void) | ||
42 | { | ||
43 | struct rlimit lim; | ||
44 | |||
45 | if(getrlimit(RLIMIT_STACK, &lim) < 0){ | ||
46 | perror("getrlimit"); | ||
47 | exit(1); | ||
48 | } | ||
49 | if((lim.rlim_cur == RLIM_INFINITY) || (lim.rlim_cur > STACKSIZE)){ | ||
50 | lim.rlim_cur = STACKSIZE; | ||
51 | if(setrlimit(RLIMIT_STACK, &lim) < 0){ | ||
52 | perror("setrlimit"); | ||
53 | exit(1); | ||
54 | } | ||
55 | } | ||
56 | stacksizelim = (lim.rlim_cur + PGD_BOUND - 1) & ~(PGD_BOUND - 1); | ||
57 | } | ||
58 | |||
59 | static __init void do_uml_initcalls(void) | ||
60 | { | ||
61 | initcall_t *call; | ||
62 | |||
63 | call = &__uml_initcall_start; | ||
64 | while (call < &__uml_initcall_end){; | ||
65 | (*call)(); | ||
66 | call++; | ||
67 | } | ||
68 | } | ||
69 | |||
70 | static void last_ditch_exit(int sig) | ||
71 | { | ||
72 | signal(SIGINT, SIG_DFL); | ||
73 | signal(SIGTERM, SIG_DFL); | ||
74 | signal(SIGHUP, SIG_DFL); | ||
75 | uml_cleanup(); | ||
76 | exit(1); | ||
77 | } | ||
78 | |||
79 | extern int uml_exitcode; | ||
80 | |||
81 | extern void scan_elf_aux( char **envp); | ||
82 | |||
83 | int main(int argc, char **argv, char **envp) | ||
84 | { | ||
85 | char **new_argv; | ||
86 | sigset_t mask; | ||
87 | int ret, i, err; | ||
88 | |||
89 | /* Enable all signals except SIGIO - in some environments, we can | ||
90 | * enter with some signals blocked | ||
91 | */ | ||
92 | |||
93 | sigemptyset(&mask); | ||
94 | sigaddset(&mask, SIGIO); | ||
95 | if(sigprocmask(SIG_SETMASK, &mask, NULL) < 0){ | ||
96 | perror("sigprocmask"); | ||
97 | exit(1); | ||
98 | } | ||
99 | |||
100 | #ifdef UML_CONFIG_CMDLINE_ON_HOST | ||
101 | /* Allocate memory for thread command lines */ | ||
102 | if(argc < 2 || strlen(argv[1]) < THREAD_NAME_LEN - 1){ | ||
103 | |||
104 | char padding[THREAD_NAME_LEN] = { | ||
105 | [ 0 ... THREAD_NAME_LEN - 2] = ' ', '\0' | ||
106 | }; | ||
107 | |||
108 | new_argv = malloc((argc + 2) * sizeof(char*)); | ||
109 | if(!new_argv) { | ||
110 | perror("Allocating extended argv"); | ||
111 | exit(1); | ||
112 | } | ||
113 | |||
114 | new_argv[0] = argv[0]; | ||
115 | new_argv[1] = padding; | ||
116 | |||
117 | for(i = 2; i <= argc; i++) | ||
118 | new_argv[i] = argv[i - 1]; | ||
119 | new_argv[argc + 1] = NULL; | ||
120 | |||
121 | execvp(new_argv[0], new_argv); | ||
122 | perror("execing with extended args"); | ||
123 | exit(1); | ||
124 | } | ||
125 | #endif | ||
126 | |||
127 | linux_prog = argv[0]; | ||
128 | |||
129 | set_stklim(); | ||
130 | |||
131 | new_argv = malloc((argc + 1) * sizeof(char *)); | ||
132 | if(new_argv == NULL){ | ||
133 | perror("Mallocing argv"); | ||
134 | exit(1); | ||
135 | } | ||
136 | for(i=0;i<argc;i++){ | ||
137 | new_argv[i] = strdup(argv[i]); | ||
138 | if(new_argv[i] == NULL){ | ||
139 | perror("Mallocing an arg"); | ||
140 | exit(1); | ||
141 | } | ||
142 | } | ||
143 | new_argv[argc] = NULL; | ||
144 | |||
145 | set_handler(SIGINT, last_ditch_exit, SA_ONESHOT | SA_NODEFER, -1); | ||
146 | set_handler(SIGTERM, last_ditch_exit, SA_ONESHOT | SA_NODEFER, -1); | ||
147 | set_handler(SIGHUP, last_ditch_exit, SA_ONESHOT | SA_NODEFER, -1); | ||
148 | |||
149 | scan_elf_aux( envp); | ||
150 | |||
151 | do_uml_initcalls(); | ||
152 | ret = linux_main(argc, argv); | ||
153 | |||
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. | ||
157 | */ | ||
158 | change_sig(SIGPROF, 0); | ||
159 | |||
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. | ||
164 | */ | ||
165 | |||
166 | /* stop timers and set SIG*ALRM to be ignored */ | ||
167 | disable_timer(); | ||
168 | |||
169 | /* disable SIGIO for the fds and set SIGIO to be ignored */ | ||
170 | err = deactivate_all_fds(); | ||
171 | if(err) | ||
172 | printf("deactivate_all_fds failed, errno = %d\n", -err); | ||
173 | |||
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. | ||
177 | */ | ||
178 | unblock_signals(); | ||
179 | |||
180 | /* Reboot */ | ||
181 | if(ret){ | ||
182 | printf("\n"); | ||
183 | execvp(new_argv[0], new_argv); | ||
184 | perror("Failed to exec kernel"); | ||
185 | ret = 1; | ||
186 | } | ||
187 | printf("\n"); | ||
188 | return(uml_exitcode); | ||
189 | } | ||
190 | |||
191 | #define CAN_KMALLOC() \ | ||
192 | (kmalloc_ok && CHOOSE_MODE((os_getpid() != tracing_pid), 1)) | ||
193 | |||
194 | extern void *__real_malloc(int); | ||
195 | |||
196 | void *__wrap_malloc(int size) | ||
197 | { | ||
198 | void *ret; | ||
199 | |||
200 | if(!CAN_KMALLOC()) | ||
201 | return(__real_malloc(size)); | ||
202 | else if(size <= PAGE_SIZE) /* finding contiguos pages can be hard*/ | ||
203 | ret = um_kmalloc(size); | ||
204 | else ret = um_vmalloc(size); | ||
205 | |||
206 | /* glibc people insist that if malloc fails, errno should be | ||
207 | * set by malloc as well. So we do. | ||
208 | */ | ||
209 | if(ret == NULL) | ||
210 | errno = ENOMEM; | ||
211 | |||
212 | return(ret); | ||
213 | } | ||
214 | |||
215 | void *__wrap_calloc(int n, int size) | ||
216 | { | ||
217 | void *ptr = __wrap_malloc(n * size); | ||
218 | |||
219 | if(ptr == NULL) return(NULL); | ||
220 | memset(ptr, 0, n * size); | ||
221 | return(ptr); | ||
222 | } | ||
223 | |||
224 | extern void __real_free(void *); | ||
225 | |||
226 | extern unsigned long high_physmem; | ||
227 | |||
228 | void __wrap_free(void *ptr) | ||
229 | { | ||
230 | unsigned long addr = (unsigned long) ptr; | ||
231 | |||
232 | /* We need to know how the allocation happened, so it can be correctly | ||
233 | * freed. This is done by seeing what region of memory the pointer is | ||
234 | * in - | ||
235 | * physical memory - kmalloc/kfree | ||
236 | * kernel virtual memory - vmalloc/vfree | ||
237 | * anywhere else - malloc/free | ||
238 | * If kmalloc is not yet possible, then either high_physmem and/or | ||
239 | * end_vm are still 0 (as at startup), in which case we call free, or | ||
240 | * we have set them, but anyway addr has not been allocated from those | ||
241 | * areas. So, in both cases __real_free is called. | ||
242 | * | ||
243 | * CAN_KMALLOC is checked because it would be bad to free a buffer | ||
244 | * with kmalloc/vmalloc after they have been turned off during | ||
245 | * shutdown. | ||
246 | * XXX: However, we sometimes shutdown CAN_KMALLOC temporarily, so | ||
247 | * there is a possibility for memory leaks. | ||
248 | */ | ||
249 | |||
250 | if((addr >= uml_physmem) && (addr < high_physmem)){ | ||
251 | if(CAN_KMALLOC()) | ||
252 | kfree(ptr); | ||
253 | } | ||
254 | else if((addr >= start_vm) && (addr < end_vm)){ | ||
255 | if(CAN_KMALLOC()) | ||
256 | vfree(ptr); | ||
257 | } | ||
258 | else __real_free(ptr); | ||
259 | } | ||