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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 000000000000..23da27d22569
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+++ 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 */
32unsigned long stacksizelim;
33
34/* Set in main */
35char *linux_prog;
36
37#define PGD_BOUND (4 * 1024 * 1024)
38#define STACKSIZE (8 * 1024 * 1024)
39#define THREAD_NAME_LEN (256)
40
41static 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
59static __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
70static 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
79extern int uml_exitcode;
80
81extern void scan_elf_aux( char **envp);
82
83int 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
194extern void *__real_malloc(int);
195
196void *__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
215void *__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
224extern void __real_free(void *);
225
226extern unsigned long high_physmem;
227
228void __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}