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: Al Viro <[email protected]>

Author: Al Viro

arch/alpha/kernel/osf_sys.c

@@ -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

@@ -185,62 +185,41 @@ 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;
 }
 
 /* hpux statfs */
 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

@@ -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);
-		if (!error)
-			error = put_compat_statfs(buf, &tmp);
-		path_put(&path);
-	}
+	struct kstatfs tmp;
+	int error = user_statfs(pathname, &tmp);
+	if (!error)
+		error = put_compat_statfs(buf, &tmp);
 	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);
-		if (!error)
-			error = put_compat_statfs64(buf, &tmp);
-		path_put(&path);
-	}
+	error = user_statfs(pathname, &tmp);
+	if (!error)
+		error = put_compat_statfs64(buf, &tmp);
 	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;
 }