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 */
27 static int coda_ioctl_permission(struct inode *inode, int mask);
28 static long coda_pioctl(struct file *filp, unsigned int cmd,
29 unsigned long user_data);
30
31 /* exported from this file */
32 const struct inode_operations coda_ioctl_inode_operations = {
33 .permission = coda_ioctl_permission,
34 .setattr = coda_setattr,
35 };
36
37 const struct file_operations coda_ioctl_operations = {
38 .unlocked_ioctl = coda_pioctl,
39 .llseek = noop_llseek,
40 };
41
42 /* the coda pioctl inode ops */
coda_ioctl_permission(struct inode * inode,int mask)43 static int coda_ioctl_permission(struct inode *inode, int mask)
44 {
45 return (mask & MAY_EXEC) ? -EACCES : 0;
46 }
47
coda_pioctl(struct file * filp,unsigned int cmd,unsigned long user_data)48 static long coda_pioctl(struct file *filp, unsigned int cmd,
49 unsigned long user_data)
50 {
51 struct path path;
52 int error;
53 struct PioctlData data;
54 struct inode *inode = file_inode(filp);
55 struct inode *target_inode = NULL;
56 struct coda_inode_info *cnp;
57
58 /* get the Pioctl data arguments from user space */
59 if (copy_from_user(&data, (void __user *)user_data, sizeof(data)))
60 return -EINVAL;
61
62 /*
63 * Look up the pathname. Note that the pathname is in
64 * user memory, and namei takes care of this
65 */
66 error = user_path_at(AT_FDCWD, data.path,
67 data.follow ? LOOKUP_FOLLOW : 0, &path);
68 if (error)
69 return error;
70
71 target_inode = d_inode(path.dentry);
72
73 /* return if it is not a Coda inode */
74 if (target_inode->i_sb != inode->i_sb) {
75 error = -EINVAL;
76 goto out;
77 }
78
79 /* now proceed to make the upcall */
80 cnp = ITOC(target_inode);
81
82 error = venus_pioctl(inode->i_sb, &(cnp->c_fid), cmd, &data);
83 out:
84 path_put(&path);
85 return error;
86 }
87
