linux/arch/um/os-Linux/process.c
Jeff Dike 5134d8fea0 uml: style fixes in arch/um/os-Linux
Style changes under arch/um/os-Linux:
	include trimming
	CodingStyle fixes
	some printks needed severity indicators

make_tempfile turns out not to be used outside of mem.c, so it is now static.
Its declaration in tempfile.h is no longer needed, and tempfile.h itself is no
longer needed.

create_tmp_file was also made static.

checkpatch moans about an EXPORT_SYMBOL in user_syms.c which is part of a
macro definition - this is copying a bit of kernel infrastructure into the
libc side of UML because the kernel headers can't be included there.

Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08 09:22:42 -08:00

270 lines
5.8 KiB
C

/*
* Copyright (C) 2002 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
* Licensed under the GPL
*/
#include <stdio.h>
#include <unistd.h>
#include <errno.h>
#include <signal.h>
#include <fcntl.h>
#include <sys/mman.h>
#include <sys/ptrace.h>
#include <sys/wait.h>
#include <asm/unistd.h>
#include "init.h"
#include "kern_constants.h"
#include "longjmp.h"
#include "os.h"
#include "process.h"
#include "skas_ptrace.h"
#include "user.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 = ARBITRARY_ADDR;
int fd, err;
sprintf(proc_stat, "/proc/%d/stat", pid);
fd = open(proc_stat, O_RDONLY, 0);
if (fd < 0) {
printk(UM_KERN_ERR "os_process_pc - couldn't open '%s', "
"errno = %d\n", proc_stat, errno);
goto out;
}
CATCH_EINTR(err = read(fd, buf, sizeof(buf)));
if (err < 0) {
printk(UM_KERN_ERR "os_process_pc - couldn't read '%s', "
"err = %d\n", proc_stat, errno);
goto out_close;
}
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(UM_KERN_ERR "os_process_pc - couldn't find pc in '%s'\n",
buf);
out_close:
close(fd);
out:
return pc;
}
int os_process_parent(int pid)
{
char stat[STAT_PATH_LEN];
char data[256];
int parent = FAILURE_PID, n, fd;
if (pid == -1)
return parent;
snprintf(stat, sizeof(stat), "/proc/%d/stat", pid);
fd = open(stat, O_RDONLY, 0);
if (fd < 0) {
printk(UM_KERN_ERR "Couldn't open '%s', errno = %d\n", stat,
errno);
return parent;
}
CATCH_EINTR(n = read(fd, data, sizeof(data)));
close(fd);
if (n < 0) {
printk(UM_KERN_ERR "Couldn't read '%s', errno = %d\n", stat,
errno);
return parent;
}
parent = FAILURE_PID;
n = sscanf(data, "%*d " COMM_SCANF " %*c %d", &parent);
if (n != 1)
printk(UM_KERN_ERR "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, __WALL));
}
/* 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, __WALL));
}
/* 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 __init can_drop_memory(void)
{
void *addr;
int fd, ok = 0;
printk(UM_KERN_INFO "Checking host MADV_REMOVE support...");
fd = create_mem_file(UM_KERN_PAGE_SIZE);
if (fd < 0) {
printk(UM_KERN_ERR "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(UM_KERN_ERR "Mapping test memory file failed, "
"err = %d\n", -errno);
goto out_close;
}
if (madvise(addr, UM_KERN_PAGE_SIZE, MADV_REMOVE) != 0) {
printk(UM_KERN_ERR "MADV_REMOVE failed, err = %d\n", -errno);
goto out_unmap;
}
printk(UM_KERN_CONT "OK\n");
ok = 1;
out_unmap:
munmap(addr, UM_KERN_PAGE_SIZE);
out_close:
close(fd);
out:
return ok;
}
void init_new_thread_signals(void)
{
set_handler(SIGSEGV, (__sighandler_t) sig_handler, SA_ONSTACK,
SIGUSR1, SIGIO, SIGWINCH, SIGVTALRM, -1);
set_handler(SIGTRAP, (__sighandler_t) sig_handler, SA_ONSTACK,
SIGUSR1, SIGIO, SIGWINCH, SIGVTALRM, -1);
set_handler(SIGFPE, (__sighandler_t) sig_handler, SA_ONSTACK,
SIGUSR1, SIGIO, SIGWINCH, SIGVTALRM, -1);
set_handler(SIGILL, (__sighandler_t) sig_handler, SA_ONSTACK,
SIGUSR1, SIGIO, SIGWINCH, SIGVTALRM, -1);
set_handler(SIGBUS, (__sighandler_t) sig_handler, SA_ONSTACK,
SIGUSR1, SIGIO, SIGWINCH, SIGVTALRM, -1);
signal(SIGHUP, SIG_IGN);
set_handler(SIGIO, (__sighandler_t) sig_handler,
SA_ONSTACK | SA_RESTART, SIGUSR1, SIGIO, SIGWINCH, SIGALRM,
SIGVTALRM, -1);
signal(SIGWINCH, SIG_IGN);
}
int run_kernel_thread(int (*fn)(void *), void *arg, jmp_buf **jmp_ptr)
{
jmp_buf buf;
int n;
*jmp_ptr = &buf;
n = UML_SETJMP(&buf);
if (n != 0)
return n;
(*fn)(arg);
return 0;
}