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7#include <stdio.h>
8#include <stdlib.h>
9#include <unistd.h>
10#include <errno.h>
11#include <signal.h>
12#include <string.h>
13#include <sys/resource.h>
14#include <as-layout.h>
15#include <init.h>
16#include <kern_util.h>
17#include <os.h>
18#include <um_malloc.h>
19
20#define PGD_BOUND (4 * 1024 * 1024)
21#define STACKSIZE (8 * 1024 * 1024)
22#define THREAD_NAME_LEN (256)
23
24long elf_aux_hwcap;
25
26static void set_stklim(void)
27{
28 struct rlimit lim;
29
30 if (getrlimit(RLIMIT_STACK, &lim) < 0) {
31 perror("getrlimit");
32 exit(1);
33 }
34 if ((lim.rlim_cur == RLIM_INFINITY) || (lim.rlim_cur > STACKSIZE)) {
35 lim.rlim_cur = STACKSIZE;
36 if (setrlimit(RLIMIT_STACK, &lim) < 0) {
37 perror("setrlimit");
38 exit(1);
39 }
40 }
41}
42
43static __init void do_uml_initcalls(void)
44{
45 initcall_t *call;
46
47 call = &__uml_initcall_start;
48 while (call < &__uml_initcall_end) {
49 (*call)();
50 call++;
51 }
52}
53
54static void last_ditch_exit(int sig)
55{
56 uml_cleanup();
57 exit(1);
58}
59
60static void install_fatal_handler(int sig)
61{
62 struct sigaction action;
63
64
65 sigemptyset(&action.sa_mask);
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73 action.sa_flags = SA_RESETHAND | SA_NODEFER;
74 action.sa_restorer = NULL;
75 action.sa_handler = last_ditch_exit;
76 if (sigaction(sig, &action, NULL) < 0) {
77 os_warn("failed to install handler for signal %d "
78 "- errno = %d\n", sig, errno);
79 exit(1);
80 }
81}
82
83#define UML_LIB_PATH ":" OS_LIB_PATH "/uml"
84
85static void setup_env_path(void)
86{
87 char *new_path = NULL;
88 char *old_path = NULL;
89 int path_len = 0;
90
91 old_path = getenv("PATH");
92
93
94
95
96 if (!old_path || (path_len = strlen(old_path)) == 0) {
97 if (putenv("PATH=:/bin:/usr/bin/" UML_LIB_PATH))
98 perror("couldn't putenv");
99 return;
100 }
101
102
103 path_len += strlen("PATH=" UML_LIB_PATH) + 1;
104 new_path = malloc(path_len);
105 if (!new_path) {
106 perror("couldn't malloc to set a new PATH");
107 return;
108 }
109 snprintf(new_path, path_len, "PATH=%s" UML_LIB_PATH, old_path);
110 if (putenv(new_path)) {
111 perror("couldn't putenv to set a new PATH");
112 free(new_path);
113 }
114}
115
116extern void scan_elf_aux( char **envp);
117
118int __init main(int argc, char **argv, char **envp)
119{
120 char **new_argv;
121 int ret, i, err;
122
123 set_stklim();
124
125 setup_env_path();
126
127 setsid();
128
129 new_argv = malloc((argc + 1) * sizeof(char *));
130 if (new_argv == NULL) {
131 perror("Mallocing argv");
132 exit(1);
133 }
134 for (i = 0; i < argc; i++) {
135 new_argv[i] = strdup(argv[i]);
136 if (new_argv[i] == NULL) {
137 perror("Mallocing an arg");
138 exit(1);
139 }
140 }
141 new_argv[argc] = NULL;
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146
147 install_fatal_handler(SIGINT);
148 install_fatal_handler(SIGTERM);
149
150#ifdef CONFIG_ARCH_REUSE_HOST_VSYSCALL_AREA
151 scan_elf_aux(envp);
152#endif
153
154 do_uml_initcalls();
155 change_sig(SIGPIPE, 0);
156 ret = linux_main(argc, argv);
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163 change_sig(SIGPROF, 0);
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172
173 os_timer_disable();
174
175
176 err = deactivate_all_fds();
177 if (err)
178 os_warn("deactivate_all_fds failed, errno = %d\n", -err);
179
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183
184
185 unblock_signals();
186
187 os_info("\n");
188
189 if (ret) {
190 execvp(new_argv[0], new_argv);
191 perror("Failed to exec kernel");
192 ret = 1;
193 }
194 return uml_exitcode;
195}
196
197extern void *__real_malloc(int);
198
199void *__wrap_malloc(int size)
200{
201 void *ret;
202
203 if (!kmalloc_ok)
204 return __real_malloc(size);
205 else if (size <= UM_KERN_PAGE_SIZE)
206
207 ret = uml_kmalloc(size, UM_GFP_KERNEL);
208 else ret = vmalloc(size);
209
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212
213
214 if (ret == NULL)
215 errno = ENOMEM;
216
217 return ret;
218}
219
220void *__wrap_calloc(int n, int size)
221{
222 void *ptr = __wrap_malloc(n * size);
223
224 if (ptr == NULL)
225 return NULL;
226 memset(ptr, 0, n * size);
227 return ptr;
228}
229
230extern void __real_free(void *);
231
232extern unsigned long high_physmem;
233
234void __wrap_free(void *ptr)
235{
236 unsigned long addr = (unsigned long) ptr;
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257 if ((addr >= uml_physmem) && (addr < high_physmem)) {
258 if (kmalloc_ok)
259 kfree(ptr);
260 }
261 else if ((addr >= start_vm) && (addr < end_vm)) {
262 if (kmalloc_ok)
263 vfree(ptr);
264 }
265 else __real_free(ptr);
266}
267