/*  * Copyright (C) 2002 Jeff Dike (jdike@addtoit.com) * Licensed under the GPL */ #include <unistd.h>#include <stdio.h>#include <errno.h>#include <signal.h>#include <sys/mman.h>#include <sys/wait.h>#include <sys/mman.h>#include <sys/syscall.h>#include "ptrace_user.h"#include "os.h"#include "user.h"#include "user_util.h"#include "process.h"#include "irq_user.h"#include "kern_util.h"#include "longjmp.h"#include "skas_ptrace.h"#include "kern_constants.h"#include "uml-config.h" #define ARBITRARY_ADDR -1#define FAILURE_PID    -1 #define STAT_PATH_LEN sizeof("/proc/#######/stat\0")#define COMM_SCANF "%*[^)])" unsigned long os_process_pc(int pid){	char proc_stat[STAT_PATH_LEN], buf[256];	unsigned long pc;	int fd, err; 	sprintf(proc_stat, "/proc/%d/stat", pid);	fd = os_open_file(proc_stat, of_read(OPENFLAGS()), 0);	if(fd < 0){		printk("os_process_pc - couldn't open '%s', err = %d\n",		       proc_stat, -fd);		return(ARBITRARY_ADDR);	}	err = os_read_file(fd, buf, sizeof(buf));	if(err < 0){		printk("os_process_pc - couldn't read '%s', err = %d\n",		       proc_stat, -err);		os_close_file(fd);		return(ARBITRARY_ADDR);	}	os_close_file(fd);	pc = ARBITRARY_ADDR;	if(sscanf(buf, "%*d " COMM_SCANF " %*c %*d %*d %*d %*d %*d %*d %*d "		  "%*d %*d %*d %*d %*d %*d %*d %*d %*d %*d %*d %*d %*d %*d "		  "%*d %*d %*d %*d %*d %lu", &pc) != 1){		printk("os_process_pc - couldn't find pc in '%s'\n", buf);	}	return(pc);} int os_process_parent(int pid){	char stat[STAT_PATH_LEN];	char data[256];	int parent, n, fd; 	if(pid == -1) return(-1); 	snprintf(stat, sizeof(stat), "/proc/%d/stat", pid);	fd = os_open_file(stat, of_read(OPENFLAGS()), 0);	if(fd < 0){		printk("Couldn't open '%s', err = %d\n", stat, -fd);		return(FAILURE_PID);	} 	n = os_read_file(fd, data, sizeof(data));	os_close_file(fd); 	if(n < 0){		printk("Couldn't read '%s', err = %d\n", stat, -n);		return(FAILURE_PID);	} 	parent = FAILURE_PID;	n = sscanf(data, "%*d " COMM_SCANF " %*c %d", &parent);	if(n != 1)		printk("Failed to scan '%s'\n", data); 	return(parent);} void os_stop_process(int pid){	kill(pid, SIGSTOP);} void os_kill_process(int pid, int reap_child){	kill(pid, SIGKILL);	if(reap_child)		CATCH_EINTR(waitpid(pid, NULL, 0));		} /* This is here uniquely to have access to the userspace errno, i.e. the one * used by ptrace in case of error. */ long os_ptrace_ldt(long pid, long addr, long data){	int ret; 	ret = ptrace(PTRACE_LDT, pid, addr, data); 	if (ret < 0)		return -errno;	return ret;} /* Kill off a ptraced child by all means available.  kill it normally first, * then PTRACE_KILL it, then PTRACE_CONT it in case it's in a run state from * which it can't exit directly. */ void os_kill_ptraced_process(int pid, int reap_child){	kill(pid, SIGKILL);	ptrace(PTRACE_KILL, pid);	ptrace(PTRACE_CONT, pid);	if(reap_child)		CATCH_EINTR(waitpid(pid, NULL, 0));} #ifdef UML_CONFIG_MODE_TTvoid os_usr1_process(int pid){	kill(pid, SIGUSR1);}#endif /* Don't use the glibc version, which caches the result in TLS. It misses some * syscalls, and also breaks with clone(), which does not unshare the TLS. */ int os_getpid(void){	return(syscall(__NR_getpid));} int os_getpgrp(void){	return getpgrp();} int os_map_memory(void *virt, int fd, unsigned long long off, unsigned long len,		  int r, int w, int x){	void *loc;	int prot; 	prot = (r ? PROT_READ : 0) | (w ? PROT_WRITE : 0) | 		(x ? PROT_EXEC : 0); 	loc = mmap64((void *) virt, len, prot, MAP_SHARED | MAP_FIXED,		     fd, off);	if(loc == MAP_FAILED)		return(-errno);	return(0);} int os_protect_memory(void *addr, unsigned long len, int r, int w, int x){        int prot = ((r ? PROT_READ : 0) | (w ? PROT_WRITE : 0) | 		    (x ? PROT_EXEC : 0));         if(mprotect(addr, len, prot) < 0)		return(-errno);        return(0);} int os_unmap_memory(void *addr, int len){        int err;         err = munmap(addr, len);	if(err < 0)		return(-errno);        return(0);} #ifndef MADV_REMOVE#define MADV_REMOVE KERNEL_MADV_REMOVE#endif int os_drop_memory(void *addr, int length){	int err; 	err = madvise(addr, length, MADV_REMOVE);	if(err < 0)		err = -errno;	return err;} int can_drop_memory(void){	void *addr;	int fd, ok = 0; 	printk("Checking host MADV_REMOVE support...");	fd = create_mem_file(UM_KERN_PAGE_SIZE);	if(fd < 0){		printk("Creating test memory file failed, err = %d\n", -fd);		goto out;	} 	addr = mmap64(NULL, UM_KERN_PAGE_SIZE, PROT_READ | PROT_WRITE,		      MAP_SHARED, fd, 0);	if(addr == MAP_FAILED){		printk("Mapping test memory file failed, err = %d\n", -errno);		goto out_close;	} 	if(madvise(addr, UM_KERN_PAGE_SIZE, MADV_REMOVE) != 0){		printk("MADV_REMOVE failed, err = %d\n", -errno);		goto out_unmap;	} 	printk("OK\n");	ok = 1; out_unmap:	munmap(addr, UM_KERN_PAGE_SIZE);out_close:	close(fd);out:	return ok;} void init_new_thread_stack(void *sig_stack, void (*usr1_handler)(int)){	int flags = 0, pages; 	if(sig_stack != NULL){		pages = (1 << UML_CONFIG_KERNEL_STACK_ORDER);		set_sigstack(sig_stack, pages * page_size());		flags = SA_ONSTACK;	}	if(usr1_handler){		struct sigaction sa; 		sa.sa_handler = usr1_handler;		sigemptyset(&sa.sa_mask);		sa.sa_flags = flags;		sa.sa_restorer = NULL;		if(sigaction(SIGUSR1, &sa, NULL) < 0)			panic("init_new_thread_stack - sigaction failed - "			      "errno = %d\n", errno);	}} void init_new_thread_signals(void){	set_handler(SIGSEGV, (__sighandler_t) sig_handler, SA_ONSTACK,		    SIGUSR1, SIGIO, SIGWINCH, SIGALRM, SIGVTALRM, -1);	set_handler(SIGTRAP, (__sighandler_t) sig_handler, SA_ONSTACK,		    SIGUSR1, SIGIO, SIGWINCH, SIGALRM, SIGVTALRM, -1);	set_handler(SIGFPE, (__sighandler_t) sig_handler, SA_ONSTACK,		    SIGUSR1, SIGIO, SIGWINCH, SIGALRM, SIGVTALRM, -1);	set_handler(SIGILL, (__sighandler_t) sig_handler, SA_ONSTACK,		    SIGUSR1, SIGIO, SIGWINCH, SIGALRM, SIGVTALRM, -1);	set_handler(SIGBUS, (__sighandler_t) sig_handler, SA_ONSTACK,		    SIGUSR1, SIGIO, SIGWINCH, SIGALRM, SIGVTALRM, -1);	set_handler(SIGUSR2, (__sighandler_t) sig_handler,		    SA_ONSTACK, SIGUSR1, SIGIO, SIGWINCH, SIGALRM, SIGVTALRM,		    -1);	signal(SIGHUP, SIG_IGN); 	init_irq_signals(1);} int run_kernel_thread(int (*fn)(void *), void *arg, void **jmp_ptr){	jmp_buf buf;	int n; 	*jmp_ptr = &buf;	n = UML_SETJMP(&buf);	if(n != 0)		return n;	(*fn)(arg);	return 0;}