File-copy from v4.4.100

This is the result of 'cp' from a linux-stable tree with the 'v4.4.100'
tag checked out (commit 26d6298789e695c9f627ce49a7bbd2286405798a) on
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git

Please refer to that tree for all history prior to this point.

Change-Id: I8a9ee2aea93cd29c52c847d0ce33091a73ae6afe
diff --git a/fs/coda/pioctl.c b/fs/coda/pioctl.c
new file mode 100644
index 0000000..f36a404
--- /dev/null
+++ b/fs/coda/pioctl.c
@@ -0,0 +1,90 @@
+/*
+ * Pioctl operations for Coda.
+ * Original version: (C) 1996 Peter Braam
+ * Rewritten for Linux 2.1: (C) 1997 Carnegie Mellon University
+ *
+ * Carnegie Mellon encourages users of this code to contribute improvements
+ * to the Coda project. Contact Peter Braam <coda@cs.cmu.edu>.
+ */
+
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/time.h>
+#include <linux/fs.h>
+#include <linux/stat.h>
+#include <linux/errno.h>
+#include <linux/string.h>
+#include <linux/namei.h>
+#include <linux/module.h>
+#include <linux/uaccess.h>
+
+#include <linux/coda.h>
+#include <linux/coda_psdev.h>
+
+#include "coda_linux.h"
+
+/* pioctl ops */
+static int coda_ioctl_permission(struct inode *inode, int mask);
+static long coda_pioctl(struct file *filp, unsigned int cmd,
+			unsigned long user_data);
+
+/* exported from this file */
+const struct inode_operations coda_ioctl_inode_operations = {
+	.permission	= coda_ioctl_permission,
+	.setattr	= coda_setattr,
+};
+
+const struct file_operations coda_ioctl_operations = {
+	.owner		= THIS_MODULE,
+	.unlocked_ioctl	= coda_pioctl,
+	.llseek		= noop_llseek,
+};
+
+/* the coda pioctl inode ops */
+static int coda_ioctl_permission(struct inode *inode, int mask)
+{
+	return (mask & MAY_EXEC) ? -EACCES : 0;
+}
+
+static long coda_pioctl(struct file *filp, unsigned int cmd,
+			unsigned long user_data)
+{
+	struct path path;
+	int error;
+	struct PioctlData data;
+	struct inode *inode = file_inode(filp);
+	struct inode *target_inode = NULL;
+	struct coda_inode_info *cnp;
+
+	/* get the Pioctl data arguments from user space */
+	if (copy_from_user(&data, (void __user *)user_data, sizeof(data)))
+		return -EINVAL;
+
+	/*
+	 * Look up the pathname. Note that the pathname is in
+	 * user memory, and namei takes care of this
+	 */
+	if (data.follow)
+		error = user_path(data.path, &path);
+	else
+		error = user_lpath(data.path, &path);
+
+	if (error)
+		return error;
+
+	target_inode = d_inode(path.dentry);
+
+	/* return if it is not a Coda inode */
+	if (target_inode->i_sb != inode->i_sb) {
+		error = -EINVAL;
+		goto out;
+	}
+
+	/* now proceed to make the upcall */
+	cnp = ITOC(target_inode);
+
+	error = venus_pioctl(inode->i_sb, &(cnp->c_fid), cmd, &data);
+out:
+	path_put(&path);
+	return error;
+}