fs.c

底层驱动开发

/* $Id: fs.c,v 1.27 2002/02/08 03:57:14 davem Exp $
 * fs.c: fs related syscall emulation for Solaris
 *
 * Copyright (C) 1997,1998 Jakub Jelinek ([e-mail])
 *
 * 1999-08-19 Implemented solaris F_FREESP (truncate)
 *            fcntl, by Jason Rappleye ([e-mail])
 */

#include <linux/types.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/fs.h>
#include <linux/namei.h>
#include <linux/mm.h>
#include <linux/file.h>
#include <linux/stat.h>
#include <linux/smp_lock.h>
#include <linux/limits.h>
#include <linux/resource.h>
#include <linux/quotaops.h>
#include <linux/mount.h>
#include <linux/vfs.h>

#include <asm/uaccess.h>
#include <asm/string.h>
#include <asm/ptrace.h>

#include "conv.h"

#define R3_VERSION	1
#define R4_VERSION	2

typedef struct {
	s32	tv_sec;
	s32	tv_nsec;
} timestruct_t;

struct sol_stat {
	u32		st_dev;
	s32		st_pad1[3];     /* network id */
	u32		st_ino;
	u32		st_mode;
	u32		st_nlink;
	u32		st_uid;
	u32		st_gid;
	u32		st_rdev;
	s32		st_pad2[2];
	s32		st_size;
	s32		st_pad3;	/* st_size, off_t expansion */
	timestruct_t	st_atime;
	timestruct_t	st_mtime;
	timestruct_t	st_ctime;
	s32		st_blksize;
	s32		st_blocks;
	char		st_fstype[16];
	s32		st_pad4[8];     /* expansion area */
};

struct sol_stat64 {
	u32		st_dev;
	s32		st_pad1[3];     /* network id */
	u64		st_ino;
	u32		st_mode;
	u32		st_nlink;
	u32		st_uid;
	u32		st_gid;
	u32		st_rdev;
	s32		st_pad2[2];
	s64		st_size;
	timestruct_t	st_atime;
	timestruct_t	st_mtime;
	timestruct_t	st_ctime;
	s64		st_blksize;
	s32		st_blocks;
	char		st_fstype[16];
	s32		st_pad4[4];     /* expansion area */
};

#define UFSMAGIC (((unsigned)'u'<<24)||((unsigned)'f'<<16)||((unsigned)'s'<<8))

static inline int putstat(struct sol_stat __user *ubuf, struct kstat *kbuf)
{
	if (kbuf->size > MAX_NON_LFS ||
	    !sysv_valid_dev(kbuf->dev) ||
	    !sysv_valid_dev(kbuf->rdev))
		return -EOVERFLOW;
	if (put_user (sysv_encode_dev(kbuf->dev), &ubuf->st_dev)	||
	    __put_user (kbuf->ino, &ubuf->st_ino)		||
	    __put_user (kbuf->mode, &ubuf->st_mode)		||
	    __put_user (kbuf->nlink, &ubuf->st_nlink)	||
	    __put_user (kbuf->uid, &ubuf->st_uid)		||
	    __put_user (kbuf->gid, &ubuf->st_gid)		||
	    __put_user (sysv_encode_dev(kbuf->rdev), &ubuf->st_rdev)	||
	    __put_user (kbuf->size, &ubuf->st_size)		||
	    __put_user (kbuf->atime.tv_sec, &ubuf->st_atime.tv_sec)	||
	    __put_user (kbuf->atime.tv_nsec, &ubuf->st_atime.tv_nsec)	||
	    __put_user (kbuf->mtime.tv_sec, &ubuf->st_mtime.tv_sec)	||
	    __put_user (kbuf->mtime.tv_nsec, &ubuf->st_mtime.tv_nsec)	||
	    __put_user (kbuf->ctime.tv_sec, &ubuf->st_ctime.tv_sec)	||
	    __put_user (kbuf->ctime.tv_nsec, &ubuf->st_ctime.tv_nsec)	||
	    __put_user (kbuf->blksize, &ubuf->st_blksize)	||
	    __put_user (kbuf->blocks, &ubuf->st_blocks)	||
	    __put_user (UFSMAGIC, (unsigned __user *)ubuf->st_fstype))
		return -EFAULT;
	return 0;
}

static inline int putstat64(struct sol_stat64 __user *ubuf, struct kstat *kbuf)
{
	if (!sysv_valid_dev(kbuf->dev) || !sysv_valid_dev(kbuf->rdev))
		return -EOVERFLOW;
	if (put_user (sysv_encode_dev(kbuf->dev), &ubuf->st_dev)	||
	    __put_user (kbuf->ino, &ubuf->st_ino)		||
	    __put_user (kbuf->mode, &ubuf->st_mode)		||
	    __put_user (kbuf->nlink, &ubuf->st_nlink)	||
	    __put_user (kbuf->uid, &ubuf->st_uid)		||
	    __put_user (kbuf->gid, &ubuf->st_gid)		||
	    __put_user (sysv_encode_dev(kbuf->rdev), &ubuf->st_rdev)	||
	    __put_user (kbuf->size, &ubuf->st_size)		||
	    __put_user (kbuf->atime.tv_sec, &ubuf->st_atime.tv_sec)	||
	    __put_user (kbuf->atime.tv_nsec, &ubuf->st_atime.tv_nsec)	||
	    __put_user (kbuf->mtime.tv_sec, &ubuf->st_mtime.tv_sec)	||
	    __put_user (kbuf->mtime.tv_nsec, &ubuf->st_mtime.tv_nsec)	||
	    __put_user (kbuf->ctime.tv_sec, &ubuf->st_ctime.tv_sec)	||
	    __put_user (kbuf->ctime.tv_nsec, &ubuf->st_ctime.tv_nsec)	||
	    __put_user (kbuf->blksize, &ubuf->st_blksize)	||
	    __put_user (kbuf->blocks, &ubuf->st_blocks)	||
	    __put_user (UFSMAGIC, (unsigned __user *)ubuf->st_fstype))
		return -EFAULT;
	return 0;
}

asmlinkage int solaris_stat(u32 filename, u32 statbuf)
{
	struct kstat s;
	int ret = vfs_stat(A(filename), &s);
	if (!ret)
		return putstat(A(statbuf), &s);
	return ret;
}

asmlinkage int solaris_xstat(int vers, u32 filename, u32 statbuf)
{
	/* Solaris doesn't bother with looking at vers, so we do neither */
	return solaris_stat(filename, statbuf);
}

asmlinkage int solaris_stat64(u32 filename, u32 statbuf)
{
	struct kstat s;
	int ret = vfs_stat(A(filename), &s);
	if (!ret)
		return putstat64(A(statbuf), &s);
	return ret;
}

asmlinkage int solaris_lstat(u32 filename, u32 statbuf)
{
	struct kstat s;
	int ret = vfs_lstat(A(filename), &s);
	if (!ret)
		return putstat(A(statbuf), &s);
	return ret;
}

asmlinkage int solaris_lxstat(int vers, u32 filename, u32 statbuf)
{
	return solaris_lstat(filename, statbuf);
}

asmlinkage int solaris_lstat64(u32 filename, u32 statbuf)
{
	struct kstat s;
	int ret = vfs_lstat(A(filename), &s);
	if (!ret)
		return putstat64(A(statbuf), &s);
	return ret;
}

asmlinkage int solaris_fstat(unsigned int fd, u32 statbuf)
{
	struct kstat s;
	int ret = vfs_fstat(fd, &s);
	if (!ret)
		return putstat(A(statbuf), &s);
	return ret;
}

asmlinkage int solaris_fxstat(int vers, u32 fd, u32 statbuf)
{
	return solaris_fstat(fd, statbuf);
}

asmlinkage int solaris_fstat64(unsigned int fd, u32 statbuf)
{
	struct kstat s;
	int ret = vfs_fstat(fd, &s);
	if (!ret)
		return putstat64(A(statbuf), &s);
	return ret;
}

asmlinkage int solaris_mknod(u32 path, u32 mode, s32 dev)
{
	int (*sys_mknod)(const char __user *,int,unsigned) = 
		(int (*)(const char __user *,int,unsigned))SYS(mknod);
	int major = sysv_major(dev);
	int minor = sysv_minor(dev);

	/* minor is guaranteed to be OK for MKDEV, major might be not */
	if (major > 0xfff)
		return -EINVAL;
	return sys_mknod(A(path), mode, new_encode_dev(MKDEV(major,minor)));
}

asmlinkage int solaris_xmknod(int vers, u32 path, u32 mode, s32 dev)
{
	return solaris_mknod(path, mode, dev);
}

asmlinkage int solaris_getdents64(unsigned int fd, void __user *dirent, unsigned int count)
{
	int (*sys_getdents)(unsigned int, void __user *, unsigned int) =
		(int (*)(unsigned int, void __user *, unsigned int))SYS(getdents);
		
	return sys_getdents(fd, dirent, count);
}

/* This statfs thingie probably will go in the near future, but... */

struct sol_statfs {
	short	f_type;
	s32	f_bsize;
	s32	f_frsize;
	s32	f_blocks;
	s32	f_bfree;
	u32	f_files;
	u32	f_ffree;
	char	f_fname[6];
	char	f_fpack[6];
};

asmlinkage int solaris_statfs(u32 path, u32 buf, int len, int fstype)
{
	int ret;
	struct statfs s;
	mm_segment_t old_fs = get_fs();
	int (*sys_statfs)(const char __user *,struct statfs __user *) = 
		(int (*)(const char __user *,struct statfs __user *))SYS(statfs);
	struct sol_statfs __user *ss = A(buf);
	
	if (len != sizeof(struct sol_statfs)) return -EINVAL;
	if (!fstype) {
		/* FIXME: mixing userland and kernel pointers */
		set_fs (KERNEL_DS);
		ret = sys_statfs(A(path), &s);
		set_fs (old_fs);
		if (!ret) {
			if (put_user (s.f_type, &ss->f_type)		||
			    __put_user (s.f_bsize, &ss->f_bsize)	||
			    __put_user (0, &ss->f_frsize)		||
			    __put_user (s.f_blocks, &ss->f_blocks)	||
			    __put_user (s.f_bfree, &ss->f_bfree)	||
			    __put_user (s.f_files, &ss->f_files)	||
			    __put_user (s.f_ffree, &ss->f_ffree)	||
			    __clear_user (&ss->f_fname, 12))
				return -EFAULT;
		}
		return ret;
	}
/* Linux can't stat unmounted filesystems so we
 * simply lie and claim 100MB of 1GB is free. Sorry.
 */
	if (put_user (fstype, &ss->f_type)		||
	    __put_user (1024, &ss->f_bsize)		||
	    __put_user (0, &ss->f_frsize)		||
	    __put_user (1024*1024, &ss->f_blocks)	||
	    __put_user (100*1024, &ss->f_bfree)		||
	    __put_user (60000, &ss->f_files)		||
	    __put_user (50000, &ss->f_ffree)		||
	    __clear_user (&ss->f_fname, 12))
		return -EFAULT;
	return 0;
}

asmlinkage int solaris_fstatfs(u32 fd, u32 buf, int len, int fstype)
{
	int ret;
	struct statfs s;
	mm_segment_t old_fs = get_fs();
	int (*sys_fstatfs)(unsigned,struct statfs __user *) = 
		(int (*)(unsigned,struct statfs __user *))SYS(fstatfs);
	struct sol_statfs __user *ss = A(buf);
	
	if (len != sizeof(struct sol_statfs)) return -EINVAL;
	if (!fstype) {
		set_fs (KERNEL_DS);
		ret = sys_fstatfs(fd, &s);
		set_fs (old_fs);
		if (!ret) {
			if (put_user (s.f_type, &ss->f_type)		||
			    __put_user (s.f_bsize, &ss->f_bsize)	||
			    __put_user (0, &ss->f_frsize)		||
			    __put_user (s.f_blocks, &ss->f_blocks)	||
			    __put_user (s.f_bfree, &ss->f_bfree)	||
			    __put_user (s.f_files, &ss->f_files)	||
			    __put_user (s.f_ffree, &ss->f_ffree)	||
			    __clear_user (&ss->f_fname, 12))
				return -EFAULT;
		}
		return ret;
	}
	/* Otherwise fstatfs is the same as statfs */
	return solaris_statfs(0, buf, len, fstype);
}

struct sol_statvfs {
	u32	f_bsize;
	u32	f_frsize;
	u32	f_blocks;
	u32	f_bfree;
	u32	f_bavail;
	u32	f_files;
	u32	f_ffree;
	u32	f_favail;
	u32	f_fsid;
	char	f_basetype[16];
	u32	f_flag;
	u32	f_namemax;
	char	f_fstr[32];
	u32	f_filler[16];
};

struct sol_statvfs64 {
	u32	f_bsize;
	u32	f_frsize;
	u64	f_blocks;
	u64	f_bfree;
	u64	f_bavail;
	u64	f_files;
	u64	f_ffree;
	u64	f_favail;
	u32	f_fsid;
	char	f_basetype[16];
	u32	f_flag;
	u32	f_namemax;
	char	f_fstr[32];
	u32	f_filler[16];
};

static int report_statvfs(struct vfsmount *mnt, struct inode *inode, u32 buf)
{
	struct kstatfs s;
	int error;
	struct sol_statvfs __user *ss = A(buf);

	error = vfs_statfs(mnt->mnt_sb, &s);
	if (!error) {
		const char *p = mnt->mnt_sb->s_type->name;
		int i = 0;
		int j = strlen (p);
		
		if (j > 15) j = 15;
		if (IS_RDONLY(inode)) i = 1;
		if (mnt->mnt_flags & MNT_NOSUID) i |= 2;
		if (!sysv_valid_dev(inode->i_sb->s_dev))
			return -EOVERFLOW;
		if (put_user (s.f_bsize, &ss->f_bsize)		||
		    __put_user (0, &ss->f_frsize)		||