Commit c8b91acc authored by Al Viro's avatar Al Viro
Browse files

clean statfs-like syscalls up 



New helpers: user_statfs() and fd_statfs(), taking userland pathname and
descriptor resp. and filling struct kstatfs.  Syscalls of statfs family
(native, compat and foreign - osf and hpux on alpha and parisc resp.)
switched to those.  Removes some boilerplate code, simplifies cleanup
on errors...

Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
parent 73d049a4

arch/alpha/kernel/osf_sys.c

+8 −28
Original line number Diff line number Diff line
@@ -230,44 +230,24 @@ linux_to_osf_statfs(struct kstatfs *linux_stat, struct osf_statfs __user *osf_st 
	return copy_to_user(osf_stat, &tmp_stat, bufsiz) ? -EFAULT : 0;

}



static int

do_osf_statfs(struct path *path, struct osf_statfs __user *buffer,

	      unsigned long bufsiz)

SYSCALL_DEFINE3(osf_statfs, const char __user *, pathname,

		struct osf_statfs __user *, buffer, unsigned long, bufsiz)

{

	struct kstatfs linux_stat;

	int error = vfs_statfs(path, &linux_stat);

	int error = user_statfs(pathname, &linux_stat);

	if (!error)

		error = linux_to_osf_statfs(&linux_stat, buffer, bufsiz);

	return error;	

}



SYSCALL_DEFINE3(osf_statfs, const char __user *, pathname,

		struct osf_statfs __user *, buffer, unsigned long, bufsiz)

{

	struct path path;

	int retval;



	retval = user_path(pathname, &path);

	if (!retval) {

		retval = do_osf_statfs(&path, buffer, bufsiz);

		path_put(&path);

	}

	return retval;

}



SYSCALL_DEFINE3(osf_fstatfs, unsigned long, fd,

		struct osf_statfs __user *, buffer, unsigned long, bufsiz)

{

	struct file *file;

	int retval;



	retval = -EBADF;

	file = fget(fd);

	if (file) {

		retval = do_osf_statfs(&file->f_path, buffer, bufsiz);

		fput(file);

	}

	return retval;

	struct kstatfs linux_stat;

	int error = fd_statfs(fd, &linux_stat);

	if (!error)

		error = linux_to_osf_statfs(&linux_stat, buffer, bufsiz);

	return error;

}



/*

arch/parisc/hpux/sys_hpux.c

+22 −43
Original line number Diff line number Diff line
@@ -185,26 +185,21 @@ struct hpux_statfs { 
     int16_t f_pad;

};



static int do_statfs_hpux(struct path *path, struct hpux_statfs *buf)

static int do_statfs_hpux(struct kstatfs *st, struct hpux_statfs __user *p)

{

	struct kstatfs st;

	int retval;

	

	retval = vfs_statfs(path, &st);

	if (retval)

		return retval;



	memset(buf, 0, sizeof(*buf));

	buf->f_type = st.f_type;

	buf->f_bsize = st.f_bsize;

	buf->f_blocks = st.f_blocks;

	buf->f_bfree = st.f_bfree;

	buf->f_bavail = st.f_bavail;

	buf->f_files = st.f_files;

	buf->f_ffree = st.f_ffree;

	buf->f_fsid[0] = st.f_fsid.val[0];

	buf->f_fsid[1] = st.f_fsid.val[1];



	struct hpux_statfs buf;

	memset(&buf, 0, sizeof(buf));

	buf.f_type = st->f_type;

	buf.f_bsize = st->f_bsize;

	buf.f_blocks = st->f_blocks;

	buf.f_bfree = st->f_bfree;

	buf.f_bavail = st->f_bavail;

	buf.f_files = st->f_files;

	buf.f_ffree = st->f_ffree;

	buf.f_fsid[0] = st->f_fsid.val[0];

	buf.f_fsid[1] = st->f_fsid.val[1];

	if (copy_to_user(p, &buf, sizeof(buf)))

		return -EFAULT;

	return 0;

}
@@ -212,35 +207,19 @@ static int do_statfs_hpux(struct path *path, struct hpux_statfs *buf) 
asmlinkage long hpux_statfs(const char __user *pathname,

						struct hpux_statfs __user *buf)

{

	struct path path;

	int error;



	error = user_path(pathname, &path);

	if (!error) {

		struct hpux_statfs tmp;

		error = do_statfs_hpux(&path, &tmp);

		if (!error && copy_to_user(buf, &tmp, sizeof(tmp)))

			error = -EFAULT;

		path_put(&path);

	}

	struct kstatfs st;

	int error = user_statfs(pathname, &st);

	if (!error)

		error = do_statfs_hpux(&st, buf);

	return error;

}



asmlinkage long hpux_fstatfs(unsigned int fd, struct hpux_statfs __user * buf)

{

	struct file *file;

	struct hpux_statfs tmp;

	int error;



	error = -EBADF;

	file = fget(fd);

	if (!file)

		goto out;

	error = do_statfs_hpux(&file->f_path, &tmp);

	if (!error && copy_to_user(buf, &tmp, sizeof(tmp)))

		error = -EFAULT;

	fput(file);

 out:

	struct kstatfs st;

	int error = fd_statfs(fd, &st);

	if (!error)

		error = do_statfs_hpux(&st, buf);

	return error;

}

fs/compat.c

+10 −38
Original line number Diff line number Diff line
@@ -262,35 +262,19 @@ static int put_compat_statfs(struct compat_statfs __user *ubuf, struct kstatfs * 
 */

asmlinkage long compat_sys_statfs(const char __user *pathname, struct compat_statfs __user *buf)

{

	struct path path;

	int error;



	error = user_path(pathname, &path);

	if (!error) {

	struct kstatfs tmp;

		error = vfs_statfs(&path, &tmp);

	int error = user_statfs(pathname, &tmp);

	if (!error)

		error = put_compat_statfs(buf, &tmp);

		path_put(&path);

	}

	return error;

}



asmlinkage long compat_sys_fstatfs(unsigned int fd, struct compat_statfs __user *buf)

{

	struct file * file;

	struct kstatfs tmp;

	int error;



	error = -EBADF;

	file = fget(fd);

	if (!file)

		goto out;

	error = vfs_statfs(&file->f_path, &tmp);

	int error = fd_statfs(fd, &tmp);

	if (!error)

		error = put_compat_statfs(buf, &tmp);

	fput(file);

out:

	return error;

}
@@ -329,41 +313,29 @@ static int put_compat_statfs64(struct compat_statfs64 __user *ubuf, struct kstat 


asmlinkage long compat_sys_statfs64(const char __user *pathname, compat_size_t sz, struct compat_statfs64 __user *buf)

{

	struct path path;

	struct kstatfs tmp;

	int error;



	if (sz != sizeof(*buf))

		return -EINVAL;



	error = user_path(pathname, &path);

	if (!error) {

		struct kstatfs tmp;

		error = vfs_statfs(&path, &tmp);

	error = user_statfs(pathname, &tmp);

	if (!error)

		error = put_compat_statfs64(buf, &tmp);

		path_put(&path);

	}

	return error;

}



asmlinkage long compat_sys_fstatfs64(unsigned int fd, compat_size_t sz, struct compat_statfs64 __user *buf)

{

	struct file * file;

	struct kstatfs tmp;

	int error;



	if (sz != sizeof(*buf))

		return -EINVAL;



	error = -EBADF;

	file = fget(fd);

	if (!file)

		goto out;

	error = vfs_statfs(&file->f_path, &tmp);

	error = fd_statfs(fd, &tmp);

	if (!error)

		error = put_compat_statfs64(buf, &tmp);

	fput(file);

out:

	return error;

}

fs/statfs.c

+81 −95
Original line number Diff line number Diff line
@@ -73,149 +73,135 @@ int vfs_statfs(struct path *path, struct kstatfs *buf) 
}

EXPORT_SYMBOL(vfs_statfs);



static int do_statfs_native(struct path *path, struct statfs *buf)

int user_statfs(const char __user *pathname, struct kstatfs *st)

{

	struct kstatfs st;

	int retval;

	struct path path;

	int error = user_path(pathname, &path);

	if (!error) {

		error = vfs_statfs(&path, st);

		path_put(&path);

	}

	return error;

}



	retval = vfs_statfs(path, &st);

	if (retval)

		return retval;

int fd_statfs(int fd, struct kstatfs *st)

{

	struct file *file = fget(fd);

	int error = -EBADF;

	if (file) {

		error = vfs_statfs(&file->f_path, st);

		fput(file);

	}

	return error;

}



static int do_statfs_native(struct kstatfs *st, struct statfs __user *p)

{

	struct statfs buf;



	if (sizeof(*buf) == sizeof(st))

		memcpy(buf, &st, sizeof(st));

	if (sizeof(buf) == sizeof(*st))

		memcpy(&buf, st, sizeof(*st));

	else {

		if (sizeof buf->f_blocks == 4) {

			if ((st.f_blocks | st.f_bfree | st.f_bavail |

			     st.f_bsize | st.f_frsize) &

		if (sizeof buf.f_blocks == 4) {

			if ((st->f_blocks | st->f_bfree | st->f_bavail |

			     st->f_bsize | st->f_frsize) &

			    0xffffffff00000000ULL)

				return -EOVERFLOW;

			/*

			 * f_files and f_ffree may be -1; it's okay to stuff

			 * that into 32 bits

			 */

			if (st.f_files != -1 &&

			    (st.f_files & 0xffffffff00000000ULL))

			if (st->f_files != -1 &&

			    (st->f_files & 0xffffffff00000000ULL))

				return -EOVERFLOW;

			if (st.f_ffree != -1 &&

			    (st.f_ffree & 0xffffffff00000000ULL))

			if (st->f_ffree != -1 &&

			    (st->f_ffree & 0xffffffff00000000ULL))

				return -EOVERFLOW;

		}



		buf->f_type = st.f_type;

		buf->f_bsize = st.f_bsize;

		buf->f_blocks = st.f_blocks;

		buf->f_bfree = st.f_bfree;

		buf->f_bavail = st.f_bavail;

		buf->f_files = st.f_files;

		buf->f_ffree = st.f_ffree;

		buf->f_fsid = st.f_fsid;

		buf->f_namelen = st.f_namelen;

		buf->f_frsize = st.f_frsize;

		buf->f_flags = st.f_flags;

		memset(buf->f_spare, 0, sizeof(buf->f_spare));

	}

		buf.f_type = st->f_type;

		buf.f_bsize = st->f_bsize;

		buf.f_blocks = st->f_blocks;

		buf.f_bfree = st->f_bfree;

		buf.f_bavail = st->f_bavail;

		buf.f_files = st->f_files;

		buf.f_ffree = st->f_ffree;

		buf.f_fsid = st->f_fsid;

		buf.f_namelen = st->f_namelen;

		buf.f_frsize = st->f_frsize;

		buf.f_flags = st->f_flags;

		memset(buf.f_spare, 0, sizeof(buf.f_spare));

	}

	if (copy_to_user(p, &buf, sizeof(buf)))

		return -EFAULT;

	return 0;

}



static int do_statfs64(struct path *path, struct statfs64 *buf)

static int do_statfs64(struct kstatfs *st, struct statfs64 __user *p)

{

	struct kstatfs st;

	int retval;



	retval = vfs_statfs(path, &st);

	if (retval)

		return retval;



	if (sizeof(*buf) == sizeof(st))

		memcpy(buf, &st, sizeof(st));

	struct statfs64 buf;

	if (sizeof(buf) == sizeof(*st))

		memcpy(&buf, st, sizeof(*st));

	else {

		buf->f_type = st.f_type;

		buf->f_bsize = st.f_bsize;

		buf->f_blocks = st.f_blocks;

		buf->f_bfree = st.f_bfree;

		buf->f_bavail = st.f_bavail;

		buf->f_files = st.f_files;

		buf->f_ffree = st.f_ffree;

		buf->f_fsid = st.f_fsid;

		buf->f_namelen = st.f_namelen;

		buf->f_frsize = st.f_frsize;

		buf->f_flags = st.f_flags;

		memset(buf->f_spare, 0, sizeof(buf->f_spare));

	}

		buf.f_type = st->f_type;

		buf.f_bsize = st->f_bsize;

		buf.f_blocks = st->f_blocks;

		buf.f_bfree = st->f_bfree;

		buf.f_bavail = st->f_bavail;

		buf.f_files = st->f_files;

		buf.f_ffree = st->f_ffree;

		buf.f_fsid = st->f_fsid;

		buf.f_namelen = st->f_namelen;

		buf.f_frsize = st->f_frsize;

		buf.f_flags = st->f_flags;

		memset(buf.f_spare, 0, sizeof(buf.f_spare));

	}

	if (copy_to_user(p, &buf, sizeof(buf)))

		return -EFAULT;

	return 0;

}



SYSCALL_DEFINE2(statfs, const char __user *, pathname, struct statfs __user *, buf)

{

	struct path path;

	int error;



	error = user_path(pathname, &path);

	if (!error) {

		struct statfs tmp;

		error = do_statfs_native(&path, &tmp);

		if (!error && copy_to_user(buf, &tmp, sizeof(tmp)))

			error = -EFAULT;

		path_put(&path);

	}

	struct kstatfs st;

	int error = user_statfs(pathname, &st);

	if (!error)

		error = do_statfs_native(&st, buf);

	return error;

}



SYSCALL_DEFINE3(statfs64, const char __user *, pathname, size_t, sz, struct statfs64 __user *, buf)

{

	struct path path;

	long error;



	struct kstatfs st;

	int error;

	if (sz != sizeof(*buf))

		return -EINVAL;

	error = user_path(pathname, &path);

	if (!error) {

		struct statfs64 tmp;

		error = do_statfs64(&path, &tmp);

		if (!error && copy_to_user(buf, &tmp, sizeof(tmp)))

			error = -EFAULT;

		path_put(&path);

	}

	error = user_statfs(pathname, &st);

	if (!error)

		error = do_statfs64(&st, buf);

	return error;

}



SYSCALL_DEFINE2(fstatfs, unsigned int, fd, struct statfs __user *, buf)

{

	struct file *file;

	struct statfs tmp;

	int error;



	error = -EBADF;

	file = fget(fd);

	if (!file)

		goto out;

	error = do_statfs_native(&file->f_path, &tmp);

	if (!error && copy_to_user(buf, &tmp, sizeof(tmp)))

		error = -EFAULT;

	fput(file);

out:

	struct kstatfs st;

	int error = fd_statfs(fd, &st);

	if (!error)

		error = do_statfs_native(&st, buf);

	return error;

}



SYSCALL_DEFINE3(fstatfs64, unsigned int, fd, size_t, sz, struct statfs64 __user *, buf)

{

	struct file *file;

	struct statfs64 tmp;

	struct kstatfs st;

	int error;



	if (sz != sizeof(*buf))

		return -EINVAL;



	error = -EBADF;

	file = fget(fd);

	if (!file)

		goto out;

	error = do_statfs64(&file->f_path, &tmp);

	if (!error && copy_to_user(buf, &tmp, sizeof(tmp)))

		error = -EFAULT;

	fput(file);

out:

	error = fd_statfs(fd, &st);

	if (!error)

		error = do_statfs64(&st, buf);

	return error;

}

include/linux/fs.h

+2 −0
Original line number Diff line number Diff line
@@ -1874,6 +1874,8 @@ extern void drop_collected_mounts(struct vfsmount *); 
extern int iterate_mounts(int (*)(struct vfsmount *, void *), void *,

			  struct vfsmount *);

extern int vfs_statfs(struct path *, struct kstatfs *);

extern int user_statfs(const char __user *, struct kstatfs *);

extern int fd_statfs(int, struct kstatfs *);

extern int statfs_by_dentry(struct dentry *, struct kstatfs *);

extern int freeze_super(struct super_block *super);

extern int thaw_super(struct super_block *super);

CRA Git | Maintained and supported by SUSTech CRA and CCSE