vfs: new helper - vfs_ustat()

... and bury user_get_super()/statfs_by_dentry() - they are
purely internal now.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 13 insertions, 8 deletions

diff --git a/fs/statfs.c b/fs/statfs.c
index 9cf04a118965..2aa6a22e0be2 100644
--- a/fs/statfs.c
+++ b/fs/statfs.c
@@ -7,6 +7,7 @@
 #include <linux/statfs.h>
 #include <linux/security.h>
 #include <linux/uaccess.h>
+#include "internal.h"
 
 static int flags_by_mnt(int mnt_flags)
 {
@@ -45,7 +46,7 @@ static int calculate_f_flags(struct vfsmount *mnt)
 		flags_by_sb(mnt->mnt_sb->s_flags);
 }
 
-int statfs_by_dentry(struct dentry *dentry, struct kstatfs *buf)
+static int statfs_by_dentry(struct dentry *dentry, struct kstatfs *buf)
 {
 	int retval;
 
@@ -205,19 +206,23 @@ SYSCALL_DEFINE3(fstatfs64, unsigned int, fd, size_t, sz, struct statfs64 __user
 	return error;
 }
 
-SYSCALL_DEFINE2(ustat, unsigned, dev, struct ustat __user *, ubuf)
+int vfs_ustat(dev_t dev, struct kstatfs *sbuf)
 {
-	struct super_block *s;
-	struct ustat tmp;
-	struct kstatfs sbuf;
+	struct super_block *s = user_get_super(dev);
 	int err;
-
-	s = user_get_super(new_decode_dev(dev));
 	if (!s)
 		return -EINVAL;
 
-	err = statfs_by_dentry(s->s_root, &sbuf);
+	err = statfs_by_dentry(s->s_root, sbuf);
 	drop_super(s);
+	return err;
+}
+
+SYSCALL_DEFINE2(ustat, unsigned, dev, struct ustat __user *, ubuf)
+{
+	struct ustat tmp;
+	struct kstatfs sbuf;
+	int err = vfs_ustat(new_decode_dev(dev), &sbuf);
 	if (err)
 		return err;