1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Pioctl operations for Coda.
4 * Original version: (C) 1996 Peter Braam
5 * Rewritten for Linux 2.1: (C) 1997 Carnegie Mellon University
6 *
7 * Carnegie Mellon encourages users of this code to contribute improvements
8 * to the Coda project. Contact Peter Braam <coda@cs.cmu.edu>.
9 */
10
11#include <linux/types.h>
12#include <linux/kernel.h>
13#include <linux/time.h>
14#include <linux/fs.h>
15#include <linux/stat.h>
16#include <linux/errno.h>
17#include <linux/string.h>
18#include <linux/namei.h>
19#include <linux/module.h>
20#include <linux/uaccess.h>
21
22#include <linux/coda.h>
23#include "coda_psdev.h"
24#include "coda_linux.h"
25
26/* pioctl ops */
27static int coda_ioctl_permission(struct mnt_idmap *idmap,
28				 struct inode *inode, int mask);
29static long coda_pioctl(struct file *filp, unsigned int cmd,
30			unsigned long user_data);
31
32/* exported from this file */
33const struct inode_operations coda_ioctl_inode_operations = {
34	.permission	= coda_ioctl_permission,
35	.setattr	= coda_setattr,
36};
37
38const struct file_operations coda_ioctl_operations = {
39	.unlocked_ioctl	= coda_pioctl,
40	.llseek		= noop_llseek,
41};
42
43/* the coda pioctl inode ops */
44static int coda_ioctl_permission(struct mnt_idmap *idmap,
45				 struct inode *inode, int mask)
46{
47	return (mask & MAY_EXEC) ? -EACCES : 0;
48}
49
50static long coda_pioctl(struct file *filp, unsigned int cmd,
51			unsigned long user_data)
52{
53	struct path path;
54	int error;
55	struct PioctlData data;
56	struct inode *inode = file_inode(filp);
57	struct inode *target_inode = NULL;
58	struct coda_inode_info *cnp;
59
60	/* get the Pioctl data arguments from user space */
61	if (copy_from_user(&data, (void __user *)user_data, sizeof(data)))
62		return -EINVAL;
63
64	/*
65	 * Look up the pathname. Note that the pathname is in
66	 * user memory, and namei takes care of this
67	 */
68	error = user_path_at(AT_FDCWD, data.path,
69			     data.follow ? LOOKUP_FOLLOW : 0, &path);
70	if (error)
71		return error;
72
73	target_inode = d_inode(path.dentry);
74
75	/* return if it is not a Coda inode */
76	if (target_inode->i_sb != inode->i_sb) {
77		error = -EINVAL;
78		goto out;
79	}
80
81	/* now proceed to make the upcall */
82	cnp = ITOC(target_inode);
83
84	error = venus_pioctl(inode->i_sb, &(cnp->c_fid), cmd, &data);
85out:
86	path_put(&path);
87	return error;
88}
89