sys_ia32.c

linux 内核源代码

/*
 * sys_ia32.c: Conversion between 32bit and 64bit native syscalls. Based on
 *             sys_sparc32 
 *
 * Copyright (C) 2000		VA Linux Co
 * Copyright (C) 2000		Don Dugger <[e-mail]>
 * Copyright (C) 1999 		Arun Sharma <[e-mail]>
 * Copyright (C) 1997,1998 	Jakub Jelinek ([e-mail])
 * Copyright (C) 1997 		David S. Miller ([e-mail])
 * Copyright (C) 2000		Hewlett-Packard Co.
 * Copyright (C) 2000		David Mosberger-Tang <[e-mail]>
 * Copyright (C) 2000,2001,2002	Andi Kleen, SuSE Labs (x86-64 port) 
 *
 * These routines maintain argument size conversion between 32bit and 64bit
 * environment. In 2.5 most of this should be moved to a generic directory. 
 *
 * This file assumes that there is a hole at the end of user address space.
 * 
 * Some of the functions are LE specific currently. These are hopefully all marked.
 * This should be fixed.
 */

#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/fs.h> 
#include <linux/file.h> 
#include <linux/signal.h>
#include <linux/syscalls.h>
#include <linux/resource.h>
#include <linux/times.h>
#include <linux/utsname.h>
#include <linux/smp.h>
#include <linux/smp_lock.h>
#include <linux/sem.h>
#include <linux/msg.h>
#include <linux/mm.h>
#include <linux/shm.h>
#include <linux/slab.h>
#include <linux/uio.h>
#include <linux/nfs_fs.h>
#include <linux/quota.h>
#include <linux/module.h>
#include <linux/sunrpc/svc.h>
#include <linux/nfsd/nfsd.h>
#include <linux/nfsd/cache.h>
#include <linux/nfsd/xdr.h>
#include <linux/nfsd/syscall.h>
#include <linux/poll.h>
#include <linux/personality.h>
#include <linux/stat.h>
#include <linux/ipc.h>
#include <linux/rwsem.h>
#include <linux/binfmts.h>
#include <linux/init.h>
#include <linux/aio_abi.h>
#include <linux/aio.h>
#include <linux/compat.h>
#include <linux/vfs.h>
#include <linux/ptrace.h>
#include <linux/highuid.h>
#include <linux/vmalloc.h>
#include <linux/fsnotify.h>
#include <linux/sysctl.h>
#include <asm/mman.h>
#include <asm/types.h>
#include <asm/uaccess.h>
#include <asm/semaphore.h>
#include <asm/atomic.h>
#include <asm/ldt.h>

#include <net/scm.h>
#include <net/sock.h>
#include <asm/ia32.h>

#define AA(__x)		((unsigned long)(__x))

int cp_compat_stat(struct kstat *kbuf, struct compat_stat __user *ubuf)
{
	compat_ino_t ino;

	typeof(ubuf->st_uid) uid = 0;
	typeof(ubuf->st_gid) gid = 0;
	SET_UID(uid, kbuf->uid);
	SET_GID(gid, kbuf->gid);
	if (!old_valid_dev(kbuf->dev) || !old_valid_dev(kbuf->rdev))
		return -EOVERFLOW;
	if (kbuf->size >= 0x7fffffff)
		return -EOVERFLOW;
	ino = kbuf->ino;
	if (sizeof(ino) < sizeof(kbuf->ino) && ino != kbuf->ino)
		return -EOVERFLOW;
	if (!access_ok(VERIFY_WRITE, ubuf, sizeof(struct compat_stat)) ||
	    __put_user (old_encode_dev(kbuf->dev), &ubuf->st_dev) ||
	    __put_user (ino, &ubuf->st_ino) ||
	    __put_user (kbuf->mode, &ubuf->st_mode) ||
	    __put_user (kbuf->nlink, &ubuf->st_nlink) ||
	    __put_user (uid, &ubuf->st_uid) ||
	    __put_user (gid, &ubuf->st_gid) ||
	    __put_user (old_encode_dev(kbuf->rdev), &ubuf->st_rdev) ||
	    __put_user (kbuf->size, &ubuf->st_size) ||
	    __put_user (kbuf->atime.tv_sec, &ubuf->st_atime) ||
	    __put_user (kbuf->atime.tv_nsec, &ubuf->st_atime_nsec) ||
	    __put_user (kbuf->mtime.tv_sec, &ubuf->st_mtime) ||
	    __put_user (kbuf->mtime.tv_nsec, &ubuf->st_mtime_nsec) ||
	    __put_user (kbuf->ctime.tv_sec, &ubuf->st_ctime) ||
	    __put_user (kbuf->ctime.tv_nsec, &ubuf->st_ctime_nsec) ||
	    __put_user (kbuf->blksize, &ubuf->st_blksize) ||
	    __put_user (kbuf->blocks, &ubuf->st_blocks))
		return -EFAULT;
	return 0;
}

asmlinkage long
sys32_truncate64(char __user * filename, unsigned long offset_low, unsigned long offset_high)
{
       return sys_truncate(filename, ((loff_t) offset_high << 32) | offset_low);
}

asmlinkage long
sys32_ftruncate64(unsigned int fd, unsigned long offset_low, unsigned long offset_high)
{
       return sys_ftruncate(fd, ((loff_t) offset_high << 32) | offset_low);
}

/* Another set for IA32/LFS -- x86_64 struct stat is different due to 
   support for 64bit inode numbers. */

static int
cp_stat64(struct stat64 __user *ubuf, struct kstat *stat)
{
	typeof(ubuf->st_uid) uid = 0;
	typeof(ubuf->st_gid) gid = 0;
	SET_UID(uid, stat->uid);
	SET_GID(gid, stat->gid);
	if (!access_ok(VERIFY_WRITE, ubuf, sizeof(struct stat64)) ||
	    __put_user(huge_encode_dev(stat->dev), &ubuf->st_dev) ||
	    __put_user (stat->ino, &ubuf->__st_ino) ||
	    __put_user (stat->ino, &ubuf->st_ino) ||
	    __put_user (stat->mode, &ubuf->st_mode) ||
	    __put_user (stat->nlink, &ubuf->st_nlink) ||
	    __put_user (uid, &ubuf->st_uid) ||
	    __put_user (gid, &ubuf->st_gid) ||
	    __put_user (huge_encode_dev(stat->rdev), &ubuf->st_rdev) ||
	    __put_user (stat->size, &ubuf->st_size) ||
	    __put_user (stat->atime.tv_sec, &ubuf->st_atime) ||
	    __put_user (stat->atime.tv_nsec, &ubuf->st_atime_nsec) ||
	    __put_user (stat->mtime.tv_sec, &ubuf->st_mtime) ||
	    __put_user (stat->mtime.tv_nsec, &ubuf->st_mtime_nsec) ||
	    __put_user (stat->ctime.tv_sec, &ubuf->st_ctime) ||
	    __put_user (stat->ctime.tv_nsec, &ubuf->st_ctime_nsec) ||
	    __put_user (stat->blksize, &ubuf->st_blksize) ||
	    __put_user (stat->blocks, &ubuf->st_blocks))
		return -EFAULT;
	return 0;
}

asmlinkage long
sys32_stat64(char __user * filename, struct stat64 __user *statbuf)
{
	struct kstat stat;
	int ret = vfs_stat(filename, &stat);
	if (!ret)
		ret = cp_stat64(statbuf, &stat);
	return ret;
}

asmlinkage long
sys32_lstat64(char __user * filename, struct stat64 __user *statbuf)
{
	struct kstat stat;
	int ret = vfs_lstat(filename, &stat);
	if (!ret)
		ret = cp_stat64(statbuf, &stat);
	return ret;
}

asmlinkage long
sys32_fstat64(unsigned int fd, struct stat64 __user *statbuf)
{
	struct kstat stat;
	int ret = vfs_fstat(fd, &stat);
	if (!ret)
		ret = cp_stat64(statbuf, &stat);
	return ret;
}

asmlinkage long
sys32_fstatat(unsigned int dfd, char __user *filename,
	      struct stat64 __user* statbuf, int flag)
{
	struct kstat stat;
	int error = -EINVAL;

	if ((flag & ~AT_SYMLINK_NOFOLLOW) != 0)
		goto out;

	if (flag & AT_SYMLINK_NOFOLLOW)
		error = vfs_lstat_fd(dfd, filename, &stat);
	else
		error = vfs_stat_fd(dfd, filename, &stat);

	if (!error)
		error = cp_stat64(statbuf, &stat);

out:
	return error;
}

/*
 * Linux/i386 didn't use to be able to handle more than
 * 4 system call parameters, so these system calls used a memory
 * block for parameter passing..
 */

struct mmap_arg_struct {
	unsigned int addr;
	unsigned int len;
	unsigned int prot;
	unsigned int flags;
	unsigned int fd;
	unsigned int offset;
};

asmlinkage long
sys32_mmap(struct mmap_arg_struct __user *arg)
{
	struct mmap_arg_struct a;
	struct file *file = NULL;
	unsigned long retval;
	struct mm_struct *mm ;

	if (copy_from_user(&a, arg, sizeof(a)))
		return -EFAULT;

	if (a.offset & ~PAGE_MASK)
		return -EINVAL; 

	if (!(a.flags & MAP_ANONYMOUS)) {
		file = fget(a.fd);
		if (!file)
			return -EBADF;
	}
	
	mm = current->mm; 
	down_write(&mm->mmap_sem); 
	retval = do_mmap_pgoff(file, a.addr, a.len, a.prot, a.flags, a.offset>>PAGE_SHIFT);
	if (file)
		fput(file);

	up_write(&mm->mmap_sem); 

	return retval;
}

asmlinkage long 
sys32_mprotect(unsigned long start, size_t len, unsigned long prot)
{
	return sys_mprotect(start,len,prot); 
}

asmlinkage long
sys32_pipe(int __user *fd)
{
	int retval;
	int fds[2];

	retval = do_pipe(fds);
	if (retval)
		goto out;
	if (copy_to_user(fd, fds, sizeof(fds)))
		retval = -EFAULT;
  out:
	return retval;
}

asmlinkage long
sys32_rt_sigaction(int sig, struct sigaction32 __user *act,
		   struct sigaction32 __user *oact,  unsigned int sigsetsize)
{
	struct k_sigaction new_ka, old_ka;
	int ret;
	compat_sigset_t set32;

	/* XXX: Don't preclude handling different sized sigset_t's.  */
	if (sigsetsize != sizeof(compat_sigset_t))
		return -EINVAL;

	if (act) {
		compat_uptr_t handler, restorer;

		if (!access_ok(VERIFY_READ, act, sizeof(*act)) ||
		    __get_user(handler, &act->sa_handler) ||
		    __get_user(new_ka.sa.sa_flags, &act->sa_flags) ||
		    __get_user(restorer, &act->sa_restorer)||
		    __copy_from_user(&set32, &act->sa_mask, sizeof(compat_sigset_t)))
			return -EFAULT;
		new_ka.sa.sa_handler = compat_ptr(handler);
		new_ka.sa.sa_restorer = compat_ptr(restorer);
		/* FIXME: here we rely on _COMPAT_NSIG_WORS to be >= than _NSIG_WORDS << 1 */
		switch (_NSIG_WORDS) {
		case 4: new_ka.sa.sa_mask.sig[3] = set32.sig[6]
				| (((long)set32.sig[7]) << 32);
		case 3: new_ka.sa.sa_mask.sig[2] = set32.sig[4]
				| (((long)set32.sig[5]) << 32);
		case 2: new_ka.sa.sa_mask.sig[1] = set32.sig[2]
				| (((long)set32.sig[3]) << 32);
		case 1: new_ka.sa.sa_mask.sig[0] = set32.sig[0]
				| (((long)set32.sig[1]) << 32);
		}
	}

	ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);

	if (!ret && oact) {
		/* FIXME: here we rely on _COMPAT_NSIG_WORS to be >= than _NSIG_WORDS << 1 */
		switch (_NSIG_WORDS) {
		case 4:
			set32.sig[7] = (old_ka.sa.sa_mask.sig[3] >> 32);
			set32.sig[6] = old_ka.sa.sa_mask.sig[3];
		case 3:
			set32.sig[5] = (old_ka.sa.sa_mask.sig[2] >> 32);
			set32.sig[4] = old_ka.sa.sa_mask.sig[2];
		case 2:
			set32.sig[3] = (old_ka.sa.sa_mask.sig[1] >> 32);
			set32.sig[2] = old_ka.sa.sa_mask.sig[1];
		case 1:
			set32.sig[1] = (old_ka.sa.sa_mask.sig[0] >> 32);
			set32.sig[0] = old_ka.sa.sa_mask.sig[0];
		}
		if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) ||
		    __put_user(ptr_to_compat(old_ka.sa.sa_handler), &oact->sa_handler) ||
		    __put_user(ptr_to_compat(old_ka.sa.sa_restorer), &oact->sa_restorer) ||
		    __put_user(old_ka.sa.sa_flags, &oact->sa_flags) ||
		    __copy_to_user(&oact->sa_mask, &set32, sizeof(compat_sigset_t)))
			return -EFAULT;
	}

	return ret;
}

asmlinkage long
sys32_sigaction (int sig, struct old_sigaction32 __user *act, struct old_sigaction32 __user *oact)
{
        struct k_sigaction new_ka, old_ka;
        int ret;

        if (act) {
		compat_old_sigset_t mask;
		compat_uptr_t handler, restorer;

		if (!access_ok(VERIFY_READ, act, sizeof(*act)) ||
		    __get_user(handler, &act->sa_handler) ||
		    __get_user(new_ka.sa.sa_flags, &act->sa_flags) ||
		    __get_user(restorer, &act->sa_restorer) ||
		    __get_user(mask, &act->sa_mask))
			return -EFAULT;

		new_ka.sa.sa_handler = compat_ptr(handler);
		new_ka.sa.sa_restorer = compat_ptr(restorer);

		siginitset(&new_ka.sa.sa_mask, mask);
        }

        ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);

	if (!ret && oact) {
		if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) ||
		    __put_user(ptr_to_compat(old_ka.sa.sa_handler), &oact->sa_handler) ||
		    __put_user(ptr_to_compat(old_ka.sa.sa_restorer), &oact->sa_restorer) ||
		    __put_user(old_ka.sa.sa_flags, &oact->sa_flags) ||
		    __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask))
			return -EFAULT;
        }

	return ret;
}

asmlinkage long
sys32_rt_sigprocmask(int how, compat_sigset_t __user *set,
			compat_sigset_t __user *oset, unsigned int sigsetsize)
{
	sigset_t s;
	compat_sigset_t s32;
	int ret;
	mm_segment_t old_fs = get_fs();
	
	if (set) {
		if (copy_from_user (&s32, set, sizeof(compat_sigset_t)))
			return -EFAULT;
		switch (_NSIG_WORDS) {
		case 4: s.sig[3] = s32.sig[6] | (((long)s32.sig[7]) << 32);
		case 3: s.sig[2] = s32.sig[4] | (((long)s32.sig[5]) << 32);
		case 2: s.sig[1] = s32.sig[2] | (((long)s32.sig[3]) << 32);
		case 1: s.sig[0] = s32.sig[0] | (((long)s32.sig[1]) << 32);
		}
	}
	set_fs (KERNEL_DS);
	ret = sys_rt_sigprocmask(how,
				 set ? (sigset_t __user *)&s : NULL,
				 oset ? (sigset_t __user *)&s : NULL,
				 sigsetsize); 
	set_fs (old_fs);
	if (ret) return ret;
	if (oset) {
		switch (_NSIG_WORDS) {
		case 4: s32.sig[7] = (s.sig[3] >> 32); s32.sig[6] = s.sig[3];
		case 3: s32.sig[5] = (s.sig[2] >> 32); s32.sig[4] = s.sig[2];
		case 2: s32.sig[3] = (s.sig[1] >> 32); s32.sig[2] = s.sig[1];
		case 1: s32.sig[1] = (s.sig[0] >> 32); s32.sig[0] = s.sig[0];
		}
		if (copy_to_user (oset, &s32, sizeof(compat_sigset_t)))
			return -EFAULT;
	}
	return 0;
}

static inline long
get_tv32(struct timeval *o, struct compat_timeval __user *i)
{
	int err = -EFAULT; 
	if (access_ok(VERIFY_READ, i, sizeof(*i))) { 
		err = __get_user(o->tv_sec, &i->tv_sec);
		err |= __get_user(o->tv_usec, &i->tv_usec);
	}
	return err; 
}

static inline long
put_tv32(struct compat_timeval __user *o, struct timeval *i)
{
	int err = -EFAULT;
	if (access_ok(VERIFY_WRITE, o, sizeof(*o))) { 
		err = __put_user(i->tv_sec, &o->tv_sec);
		err |= __put_user(i->tv_usec, &o->tv_usec);
	} 
	return err; 
}

extern unsigned int alarm_setitimer(unsigned int seconds);

asmlinkage long
sys32_alarm(unsigned int seconds)
{
	return alarm_setitimer(seconds);
}