1 /* 2 * Copyright (C) 2002 Jeff Dike (jdike@addtoit.com) 3 * Licensed under the GPL 4 */ 5 6 #include <unistd.h> 7 #include <stdio.h> 8 #include <errno.h> 9 #include <signal.h> 10 #include <setjmp.h> 11 #include <linux/unistd.h> 12 #include <sys/mman.h> 13 #include <sys/wait.h> 14 #include "ptrace_user.h" 15 #include "os.h" 16 #include "user.h" 17 #include "user_util.h" 18 #include "process.h" 19 #include "irq_user.h" 20 #include "kern_util.h" 21 22 #define ARBITRARY_ADDR -1 23 #define FAILURE_PID -1 24 25 #define STAT_PATH_LEN sizeof("/proc/#######/stat\0") 26 #define COMM_SCANF "%*[^)])" 27 28 unsigned long os_process_pc(int pid) 29 { 30 char proc_stat[STAT_PATH_LEN], buf[256]; 31 unsigned long pc; 32 int fd, err; 33 34 sprintf(proc_stat, "/proc/%d/stat", pid); 35 fd = os_open_file(proc_stat, of_read(OPENFLAGS()), 0); 36 if(fd < 0){ 37 printk("os_process_pc - couldn't open '%s', err = %d\n", 38 proc_stat, -fd); 39 return(ARBITRARY_ADDR); 40 } 41 err = os_read_file(fd, buf, sizeof(buf)); 42 if(err < 0){ 43 printk("os_process_pc - couldn't read '%s', err = %d\n", 44 proc_stat, -err); 45 os_close_file(fd); 46 return(ARBITRARY_ADDR); 47 } 48 os_close_file(fd); 49 pc = ARBITRARY_ADDR; 50 if(sscanf(buf, "%*d " COMM_SCANF " %*c %*d %*d %*d %*d %*d %*d %*d " 51 "%*d %*d %*d %*d %*d %*d %*d %*d %*d %*d %*d %*d %*d %*d " 52 "%*d %*d %*d %*d %*d %lu", &pc) != 1){ 53 printk("os_process_pc - couldn't find pc in '%s'\n", buf); 54 } 55 return(pc); 56 } 57 58 int os_process_parent(int pid) 59 { 60 char stat[STAT_PATH_LEN]; 61 char data[256]; 62 int parent, n, fd; 63 64 if(pid == -1) return(-1); 65 66 snprintf(stat, sizeof(stat), "/proc/%d/stat", pid); 67 fd = os_open_file(stat, of_read(OPENFLAGS()), 0); 68 if(fd < 0){ 69 printk("Couldn't open '%s', err = %d\n", stat, -fd); 70 return(FAILURE_PID); 71 } 72 73 n = os_read_file(fd, data, sizeof(data)); 74 os_close_file(fd); 75 76 if(n < 0){ 77 printk("Couldn't read '%s', err = %d\n", stat, -n); 78 return(FAILURE_PID); 79 } 80 81 parent = FAILURE_PID; 82 n = sscanf(data, "%*d " COMM_SCANF " %*c %d", &parent); 83 if(n != 1) 84 printk("Failed to scan '%s'\n", data); 85 86 return(parent); 87 } 88 89 void os_stop_process(int pid) 90 { 91 kill(pid, SIGSTOP); 92 } 93 94 void os_kill_process(int pid, int reap_child) 95 { 96 kill(pid, SIGKILL); 97 if(reap_child) 98 CATCH_EINTR(waitpid(pid, NULL, 0)); 99 100 } 101 102 /* Kill off a ptraced child by all means available. kill it normally first, 103 * then PTRACE_KILL it, then PTRACE_CONT it in case it's in a run state from 104 * which it can't exit directly. 105 */ 106 107 void os_kill_ptraced_process(int pid, int reap_child) 108 { 109 kill(pid, SIGKILL); 110 ptrace(PTRACE_KILL, pid); 111 ptrace(PTRACE_CONT, pid); 112 if(reap_child) 113 CATCH_EINTR(waitpid(pid, NULL, 0)); 114 } 115 116 void os_usr1_process(int pid) 117 { 118 kill(pid, SIGUSR1); 119 } 120 121 /* Don't use the glibc version, which caches the result in TLS. It misses some 122 * syscalls, and also breaks with clone(), which does not unshare the TLS. 123 */ 124 125 inline _syscall0(pid_t, getpid) 126 127 int os_getpid(void) 128 { 129 return(getpid()); 130 } 131 132 int os_getpgrp(void) 133 { 134 return getpgrp(); 135 } 136 137 int os_map_memory(void *virt, int fd, unsigned long long off, unsigned long len, 138 int r, int w, int x) 139 { 140 void *loc; 141 int prot; 142 143 prot = (r ? PROT_READ : 0) | (w ? PROT_WRITE : 0) | 144 (x ? PROT_EXEC : 0); 145 146 loc = mmap64((void *) virt, len, prot, MAP_SHARED | MAP_FIXED, 147 fd, off); 148 if(loc == MAP_FAILED) 149 return(-errno); 150 return(0); 151 } 152 153 int os_protect_memory(void *addr, unsigned long len, int r, int w, int x) 154 { 155 int prot = ((r ? PROT_READ : 0) | (w ? PROT_WRITE : 0) | 156 (x ? PROT_EXEC : 0)); 157 158 if(mprotect(addr, len, prot) < 0) 159 return(-errno); 160 return(0); 161 } 162 163 int os_unmap_memory(void *addr, int len) 164 { 165 int err; 166 167 err = munmap(addr, len); 168 if(err < 0) 169 return(-errno); 170 return(0); 171 } 172 173 void init_new_thread_stack(void *sig_stack, void (*usr1_handler)(int)) 174 { 175 int flags = 0, pages; 176 177 if(sig_stack != NULL){ 178 pages = (1 << UML_CONFIG_KERNEL_STACK_ORDER); 179 set_sigstack(sig_stack, pages * page_size()); 180 flags = SA_ONSTACK; 181 } 182 if(usr1_handler) set_handler(SIGUSR1, usr1_handler, flags, -1); 183 } 184 185 void init_new_thread_signals(int altstack) 186 { 187 int flags = altstack ? SA_ONSTACK : 0; 188 189 set_handler(SIGSEGV, (__sighandler_t) sig_handler, flags, 190 SIGUSR1, SIGIO, SIGWINCH, SIGALRM, SIGVTALRM, -1); 191 set_handler(SIGTRAP, (__sighandler_t) sig_handler, flags, 192 SIGUSR1, SIGIO, SIGWINCH, SIGALRM, SIGVTALRM, -1); 193 set_handler(SIGFPE, (__sighandler_t) sig_handler, flags, 194 SIGUSR1, SIGIO, SIGWINCH, SIGALRM, SIGVTALRM, -1); 195 set_handler(SIGILL, (__sighandler_t) sig_handler, flags, 196 SIGUSR1, SIGIO, SIGWINCH, SIGALRM, SIGVTALRM, -1); 197 set_handler(SIGBUS, (__sighandler_t) sig_handler, flags, 198 SIGUSR1, SIGIO, SIGWINCH, SIGALRM, SIGVTALRM, -1); 199 set_handler(SIGUSR2, (__sighandler_t) sig_handler, 200 flags, SIGUSR1, SIGIO, SIGWINCH, SIGALRM, SIGVTALRM, -1); 201 signal(SIGHUP, SIG_IGN); 202 203 init_irq_signals(altstack); 204 } 205 206 int run_kernel_thread(int (*fn)(void *), void *arg, void **jmp_ptr) 207 { 208 sigjmp_buf buf; 209 int n; 210 211 *jmp_ptr = &buf; 212 n = sigsetjmp(buf, 1); 213 if(n != 0) 214 return(n); 215 (*fn)(arg); 216 return(0); 217 } 218 219 /* 220 * Overrides for Emacs so that we follow Linus's tabbing style. 221 * Emacs will notice this stuff at the end of the file and automatically 222 * adjust the settings for this buffer only. This must remain at the end 223 * of the file. 224 * --------------------------------------------------------------------------- 225 * Local variables: 226 * c-file-style: "linux" 227 * End: 228 */ 229