init: add an init_mknod helper

Add a simple helper to mknod with a kernel space file name and switch
the early init code over to it.  Remove the now unused ksys_mknod.

Signed-off-by: Christoph Hellwig <hch@lst.de>

3 files changed, 26 insertions, 3 deletions

diff --git a/fs/init.c b/fs/init.c
index 127033d08426..145fb31b7a5f 100644
--- a/fs/init.c
+++ b/fs/init.c
@@ -122,6 +122,31 @@ int __init init_eaccess(const char *filename)
 	return error;
 }
 
+int __init init_mknod(const char *filename, umode_t mode, unsigned int dev)
+{
+	struct dentry *dentry;
+	struct path path;
+	int error;
+
+	if (S_ISFIFO(mode) || S_ISSOCK(mode))
+		dev = 0;
+	else if (!(S_ISBLK(mode) || S_ISCHR(mode)))
+		return -EINVAL;
+
+	dentry = kern_path_create(AT_FDCWD, filename, &path, 0);
+	if (IS_ERR(dentry))
+		return PTR_ERR(dentry);
+
+	if (!IS_POSIXACL(path.dentry->d_inode))
+		mode &= ~current_umask();
+	error = security_path_mknod(&path, dentry, mode, dev);
+	if (!error)
+		error = vfs_mknod(path.dentry->d_inode, dentry, mode,
+				  new_decode_dev(dev));
+	done_path_create(&path, dentry);
+	return error;
+}
+
 int __init init_link(const char *oldname, const char *newname)
 {
 	struct dentry *new_dentry;
diff --git a/fs/internal.h b/fs/internal.h
index 4741e591e923..07e145b2f88c 100644
--- a/fs/internal.h
+++ b/fs/internal.h
@@ -62,8 +62,6 @@ extern int filename_lookup(int dfd, struct filename *name, unsigned flags,
 			   struct path *path, struct path *root);
 extern int vfs_path_lookup(struct dentry *, struct vfsmount *,
 			   const char *, unsigned int, struct path *);
-long do_mknodat(int dfd, const char __user *filename, umode_t mode,
-		unsigned int dev);
 long do_rmdir(int dfd, struct filename *name);
 long do_unlinkat(int dfd, struct filename *name);
 int may_linkat(struct path *link);
diff --git a/fs/namei.c b/fs/namei.c
index d6b25dd32f4d..fde8fe086c09 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -3564,7 +3564,7 @@ static int may_mknod(umode_t mode)
 	}
 }
 
-long do_mknodat(int dfd, const char __user *filename, umode_t mode,
+static long do_mknodat(int dfd, const char __user *filename, umode_t mode,
 		unsigned int dev)
 {
 	struct dentry *dentry;