linux32.c

LINUX 2.6.17.4的源码

/*
 * Conversion between 32-bit and 64-bit native system calls.
 *
 * Copyright (C) 2000 Silicon Graphics, Inc.
 * Written by Ulf Carlsson ([e-mail])
 * sys32_execve from ia64/ia32 code, Feb 2000, Kanoj Sarcar ([e-mail])
 */
#include <linux/config.h>
#include <linux/compiler.h>
#include <linux/mm.h>
#include <linux/errno.h>
#include <linux/file.h>
#include <linux/smp_lock.h>
#include <linux/highuid.h>
#include <linux/dirent.h>
#include <linux/resource.h>
#include <linux/highmem.h>
#include <linux/time.h>
#include <linux/times.h>
#include <linux/poll.h>
#include <linux/slab.h>
#include <linux/skbuff.h>
#include <linux/filter.h>
#include <linux/shm.h>
#include <linux/sem.h>
#include <linux/msg.h>
#include <linux/icmpv6.h>
#include <linux/syscalls.h>
#include <linux/sysctl.h>
#include <linux/utime.h>
#include <linux/utsname.h>
#include <linux/personality.h>
#include <linux/dnotify.h>
#include <linux/module.h>
#include <linux/binfmts.h>
#include <linux/security.h>
#include <linux/compat.h>
#include <linux/vfs.h>

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

#include <asm/ipc.h>
#include <asm/sim.h>
#include <asm/uaccess.h>
#include <asm/mmu_context.h>
#include <asm/mman.h>

/* Use this to get at 32-bit user passed pointers. */
/* A() macro should be used for places where you e.g.
   have some internal variable u32 and just want to get
   rid of a compiler warning. AA() has to be used in
   places where you want to convert a function argument
   to 32bit pointer or when you e.g. access pt_regs
   structure and want to consider 32bit registers only.
 */
#define A(__x) ((unsigned long)(__x))
#define AA(__x) ((unsigned long)((int)__x))

#ifdef __MIPSEB__
#define merge_64(r1,r2)	((((r1) & 0xffffffffUL) << 32) + ((r2) & 0xffffffffUL))
#endif
#ifdef __MIPSEL__
#define merge_64(r1,r2)	((((r2) & 0xffffffffUL) << 32) + ((r1) & 0xffffffffUL))
#endif

/*
 * Revalidate the inode. This is required for proper NFS attribute caching.
 */

int cp_compat_stat(struct kstat *stat, struct compat_stat __user *statbuf)
{
	struct compat_stat tmp;

	if (!new_valid_dev(stat->dev) || !new_valid_dev(stat->rdev))
		return -EOVERFLOW;

	memset(&tmp, 0, sizeof(tmp));
	tmp.st_dev = new_encode_dev(stat->dev);
	tmp.st_ino = stat->ino;
	tmp.st_mode = stat->mode;
	tmp.st_nlink = stat->nlink;
	SET_UID(tmp.st_uid, stat->uid);
	SET_GID(tmp.st_gid, stat->gid);
	tmp.st_rdev = new_encode_dev(stat->rdev);
	tmp.st_size = stat->size;
	tmp.st_atime = stat->atime.tv_sec;
	tmp.st_mtime = stat->mtime.tv_sec;
	tmp.st_ctime = stat->ctime.tv_sec;
#ifdef STAT_HAVE_NSEC
	tmp.st_atime_nsec = stat->atime.tv_nsec;
	tmp.st_mtime_nsec = stat->mtime.tv_nsec;
	tmp.st_ctime_nsec = stat->ctime.tv_nsec;
#endif
	tmp.st_blocks = stat->blocks;
	tmp.st_blksize = stat->blksize;
	return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0;
}

asmlinkage unsigned long
sys32_mmap2(unsigned long addr, unsigned long len, unsigned long prot,
         unsigned long flags, unsigned long fd, unsigned long pgoff)
{
	struct file * file = NULL;
	unsigned long error;

	error = -EINVAL;
	if (pgoff & (~PAGE_MASK >> 12))
		goto out;
	pgoff >>= PAGE_SHIFT-12;

	if (!(flags & MAP_ANONYMOUS)) {
		error = -EBADF;
		file = fget(fd);
		if (!file)
			goto out;
	}
	flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);

	down_write(&current->mm->mmap_sem);
	error = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
	up_write(&current->mm->mmap_sem);
	if (file)
		fput(file);

out:
	return error;
}


asmlinkage int sys_truncate64(const char __user *path, unsigned int high,
			      unsigned int low)
{
	if ((int)high < 0)
		return -EINVAL;
	return sys_truncate(path, ((long) high << 32) | low);
}

asmlinkage int sys_ftruncate64(unsigned int fd, unsigned int high,
			       unsigned int low)
{
	if ((int)high < 0)
		return -EINVAL;
	return sys_ftruncate(fd, ((long) high << 32) | low);
}

/*
 * sys_execve() executes a new program.
 */
asmlinkage int sys32_execve(nabi_no_regargs struct pt_regs regs)
{
	int error;
	char * filename;

	filename = getname(compat_ptr(regs.regs[4]));
	error = PTR_ERR(filename);
	if (IS_ERR(filename))
		goto out;
	error = compat_do_execve(filename, compat_ptr(regs.regs[5]),
				 compat_ptr(regs.regs[6]), &regs);
	putname(filename);

out:
	return error;
}

asmlinkage long
sysn32_waitid(int which, compat_pid_t pid,
	      siginfo_t __user *uinfo, int options,
	      struct compat_rusage __user *uru)
{
	struct rusage ru;
	long ret;
	mm_segment_t old_fs = get_fs();
	int si_signo;

	if (!access_ok(VERIFY_WRITE, uinfo, sizeof(*uinfo)))
		return -EFAULT;

	set_fs (KERNEL_DS);
	ret = sys_waitid(which, pid, uinfo, options,
			 uru ? (struct rusage __user *) &ru : NULL);
	set_fs (old_fs);

	if (__get_user(si_signo, &uinfo->si_signo))
		return -EFAULT;
	if (ret < 0 || si_signo == 0)
		return ret;

	if (uru)
		ret = put_compat_rusage(&ru, uru);
	return ret;
}

struct sysinfo32 {
        s32 uptime;
        u32 loads[3];
        u32 totalram;
        u32 freeram;
        u32 sharedram;
        u32 bufferram;
        u32 totalswap;
        u32 freeswap;
        u16 procs;
	u32 totalhigh;
	u32 freehigh;
	u32 mem_unit;
	char _f[8];
};

asmlinkage int sys32_sysinfo(struct sysinfo32 __user *info)
{
	struct sysinfo s;
	int ret, err;
	mm_segment_t old_fs = get_fs ();

	set_fs (KERNEL_DS);
	ret = sys_sysinfo((struct sysinfo __user *)&s);
	set_fs (old_fs);
	err = put_user (s.uptime, &info->uptime);
	err |= __put_user (s.loads[0], &info->loads[0]);
	err |= __put_user (s.loads[1], &info->loads[1]);
	err |= __put_user (s.loads[2], &info->loads[2]);
	err |= __put_user (s.totalram, &info->totalram);
	err |= __put_user (s.freeram, &info->freeram);
	err |= __put_user (s.sharedram, &info->sharedram);
	err |= __put_user (s.bufferram, &info->bufferram);
	err |= __put_user (s.totalswap, &info->totalswap);
	err |= __put_user (s.freeswap, &info->freeswap);
	err |= __put_user (s.procs, &info->procs);
	err |= __put_user (s.totalhigh, &info->totalhigh);
	err |= __put_user (s.freehigh, &info->freehigh);
	err |= __put_user (s.mem_unit, &info->mem_unit);
	if (err)
		return -EFAULT;
	return ret;
}

#define RLIM_INFINITY32	0x7fffffff
#define RESOURCE32(x) ((x > RLIM_INFINITY32) ? RLIM_INFINITY32 : x)

struct rlimit32 {
	int	rlim_cur;
	int	rlim_max;
};

#ifdef __MIPSEB__
asmlinkage long sys32_truncate64(const char __user * path, unsigned long __dummy,
	int length_hi, int length_lo)
#endif
#ifdef __MIPSEL__
asmlinkage long sys32_truncate64(const char __user * path, unsigned long __dummy,
	int length_lo, int length_hi)
#endif
{
	loff_t length;

	length = ((unsigned long) length_hi << 32) | (unsigned int) length_lo;

	return sys_truncate(path, length);
}

#ifdef __MIPSEB__
asmlinkage long sys32_ftruncate64(unsigned int fd, unsigned long __dummy,
	int length_hi, int length_lo)
#endif
#ifdef __MIPSEL__
asmlinkage long sys32_ftruncate64(unsigned int fd, unsigned long __dummy,
	int length_lo, int length_hi)
#endif
{
	loff_t length;

	length = ((unsigned long) length_hi << 32) | (unsigned int) length_lo;

	return sys_ftruncate(fd, length);
}

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

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

extern struct timezone sys_tz;

asmlinkage int
sys32_gettimeofday(struct compat_timeval __user *tv, struct timezone __user *tz)
{
	if (tv) {
		struct timeval ktv;
		do_gettimeofday(&ktv);
		if (put_tv32(tv, &ktv))
			return -EFAULT;
	}
	if (tz) {
		if (copy_to_user(tz, &sys_tz, sizeof(sys_tz)))
			return -EFAULT;
	}
	return 0;
}

static inline long get_ts32(struct timespec *o, struct compat_timeval __user *i)
{
	long usec;

	if (!access_ok(VERIFY_READ, i, sizeof(*i)))
		return -EFAULT;
	if (__get_user(o->tv_sec, &i->tv_sec))
		return -EFAULT;
	if (__get_user(usec, &i->tv_usec))
		return -EFAULT;
	o->tv_nsec = usec * 1000;
		return 0;
}

asmlinkage int
sys32_settimeofday(struct compat_timeval __user *tv, struct timezone __user *tz)
{
	struct timespec kts;
	struct timezone ktz;

 	if (tv) {
		if (get_ts32(&kts, tv))
			return -EFAULT;
	}
	if (tz) {
		if (copy_from_user(&ktz, tz, sizeof(ktz)))
			return -EFAULT;
	}

	return do_sys_settimeofday(tv ? &kts : NULL, tz ? &ktz : NULL);
}

asmlinkage int sys32_llseek(unsigned int fd, unsigned int offset_high,
			    unsigned int offset_low, loff_t __user * result,
			    unsigned int origin)
{
	return sys_llseek(fd, offset_high, offset_low, result, origin);
}

/* From the Single Unix Spec: pread & pwrite act like lseek to pos + op +
   lseek back to original location.  They fail just like lseek does on
   non-seekable files.  */

asmlinkage ssize_t sys32_pread(unsigned int fd, char __user * buf,
			       size_t count, u32 unused, u64 a4, u64 a5)
{
	return sys_pread64(fd, buf, count, merge_64(a4, a5));
}

asmlinkage ssize_t sys32_pwrite(unsigned int fd, const char __user * buf,
			        size_t count, u32 unused, u64 a4, u64 a5)
{
	return sys_pwrite64(fd, buf, count, merge_64(a4, a5));
}

asmlinkage int sys32_sched_rr_get_interval(compat_pid_t pid,
	struct compat_timespec __user *interval)
{
	struct timespec t;
	int ret;
	mm_segment_t old_fs = get_fs ();

	set_fs (KERNEL_DS);
	ret = sys_sched_rr_get_interval(pid, (struct timespec __user *)&t);
	set_fs (old_fs);
	if (put_user (t.tv_sec, &interval->tv_sec) ||
	    __put_user (t.tv_nsec, &interval->tv_nsec))
		return -EFAULT;
	return ret;
}

struct msgbuf32 { s32 mtype; char mtext[1]; };

struct ipc_perm32
{
	key_t    	  key;
        __compat_uid_t  uid;
        __compat_gid_t  gid;
        __compat_uid_t  cuid;
        __compat_gid_t  cgid;
        compat_mode_t	mode;
        unsigned short  seq;
};

struct ipc64_perm32 {
	key_t key;
	__compat_uid_t uid;
	__compat_gid_t gid;
	__compat_uid_t cuid;
	__compat_gid_t cgid;
	compat_mode_t	mode;
	unsigned short	seq;
	unsigned short __pad1;
	unsigned int __unused1;
	unsigned int __unused2;
};

struct semid_ds32 {
        struct ipc_perm32 sem_perm;               /* permissions .. see ipc.h */
        compat_time_t   sem_otime;              /* last semop time */
        compat_time_t   sem_ctime;              /* last change time */
        u32 sem_base;              /* ptr to first semaphore in array */
        u32 sem_pending;          /* pending operations to be processed */
        u32 sem_pending_last;    /* last pending operation */
        u32 undo;                  /* undo requests on this array */
        unsigned short  sem_nsems;              /* no. of semaphores in array */
};

struct semid64_ds32 {
	struct ipc64_perm32	sem_perm;
	compat_time_t	sem_otime;
	compat_time_t	sem_ctime;
	unsigned int		sem_nsems;
	unsigned int		__unused1;
	unsigned int		__unused2;
};

struct msqid_ds32
{
        struct ipc_perm32 msg_perm;
        u32 msg_first;
        u32 msg_last;
        compat_time_t   msg_stime;
        compat_time_t   msg_rtime;