xref: /OK3568_Linux_fs/kernel/fs/coda/pioctl.c (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun  * Pioctl operations for Coda.
4*4882a593Smuzhiyun  * Original version: (C) 1996 Peter Braam
5*4882a593Smuzhiyun  * Rewritten for Linux 2.1: (C) 1997 Carnegie Mellon University
6*4882a593Smuzhiyun  *
7*4882a593Smuzhiyun  * Carnegie Mellon encourages users of this code to contribute improvements
8*4882a593Smuzhiyun  * to the Coda project. Contact Peter Braam <coda@cs.cmu.edu>.
9*4882a593Smuzhiyun  */
10*4882a593Smuzhiyun 
11*4882a593Smuzhiyun #include <linux/types.h>
12*4882a593Smuzhiyun #include <linux/kernel.h>
13*4882a593Smuzhiyun #include <linux/time.h>
14*4882a593Smuzhiyun #include <linux/fs.h>
15*4882a593Smuzhiyun #include <linux/stat.h>
16*4882a593Smuzhiyun #include <linux/errno.h>
17*4882a593Smuzhiyun #include <linux/string.h>
18*4882a593Smuzhiyun #include <linux/namei.h>
19*4882a593Smuzhiyun #include <linux/module.h>
20*4882a593Smuzhiyun #include <linux/uaccess.h>
21*4882a593Smuzhiyun 
22*4882a593Smuzhiyun #include <linux/coda.h>
23*4882a593Smuzhiyun #include "coda_psdev.h"
24*4882a593Smuzhiyun #include "coda_linux.h"
25*4882a593Smuzhiyun 
26*4882a593Smuzhiyun /* pioctl ops */
27*4882a593Smuzhiyun static int coda_ioctl_permission(struct inode *inode, int mask);
28*4882a593Smuzhiyun static long coda_pioctl(struct file *filp, unsigned int cmd,
29*4882a593Smuzhiyun 			unsigned long user_data);
30*4882a593Smuzhiyun 
31*4882a593Smuzhiyun /* exported from this file */
32*4882a593Smuzhiyun const struct inode_operations coda_ioctl_inode_operations = {
33*4882a593Smuzhiyun 	.permission	= coda_ioctl_permission,
34*4882a593Smuzhiyun 	.setattr	= coda_setattr,
35*4882a593Smuzhiyun };
36*4882a593Smuzhiyun 
37*4882a593Smuzhiyun const struct file_operations coda_ioctl_operations = {
38*4882a593Smuzhiyun 	.unlocked_ioctl	= coda_pioctl,
39*4882a593Smuzhiyun 	.llseek		= noop_llseek,
40*4882a593Smuzhiyun };
41*4882a593Smuzhiyun 
42*4882a593Smuzhiyun /* the coda pioctl inode ops */
coda_ioctl_permission(struct inode * inode,int mask)43*4882a593Smuzhiyun static int coda_ioctl_permission(struct inode *inode, int mask)
44*4882a593Smuzhiyun {
45*4882a593Smuzhiyun 	return (mask & MAY_EXEC) ? -EACCES : 0;
46*4882a593Smuzhiyun }
47*4882a593Smuzhiyun 
coda_pioctl(struct file * filp,unsigned int cmd,unsigned long user_data)48*4882a593Smuzhiyun static long coda_pioctl(struct file *filp, unsigned int cmd,
49*4882a593Smuzhiyun 			unsigned long user_data)
50*4882a593Smuzhiyun {
51*4882a593Smuzhiyun 	struct path path;
52*4882a593Smuzhiyun 	int error;
53*4882a593Smuzhiyun 	struct PioctlData data;
54*4882a593Smuzhiyun 	struct inode *inode = file_inode(filp);
55*4882a593Smuzhiyun 	struct inode *target_inode = NULL;
56*4882a593Smuzhiyun 	struct coda_inode_info *cnp;
57*4882a593Smuzhiyun 
58*4882a593Smuzhiyun 	/* get the Pioctl data arguments from user space */
59*4882a593Smuzhiyun 	if (copy_from_user(&data, (void __user *)user_data, sizeof(data)))
60*4882a593Smuzhiyun 		return -EINVAL;
61*4882a593Smuzhiyun 
62*4882a593Smuzhiyun 	/*
63*4882a593Smuzhiyun 	 * Look up the pathname. Note that the pathname is in
64*4882a593Smuzhiyun 	 * user memory, and namei takes care of this
65*4882a593Smuzhiyun 	 */
66*4882a593Smuzhiyun 	error = user_path_at(AT_FDCWD, data.path,
67*4882a593Smuzhiyun 			     data.follow ? LOOKUP_FOLLOW : 0, &path);
68*4882a593Smuzhiyun 	if (error)
69*4882a593Smuzhiyun 		return error;
70*4882a593Smuzhiyun 
71*4882a593Smuzhiyun 	target_inode = d_inode(path.dentry);
72*4882a593Smuzhiyun 
73*4882a593Smuzhiyun 	/* return if it is not a Coda inode */
74*4882a593Smuzhiyun 	if (target_inode->i_sb != inode->i_sb) {
75*4882a593Smuzhiyun 		error = -EINVAL;
76*4882a593Smuzhiyun 		goto out;
77*4882a593Smuzhiyun 	}
78*4882a593Smuzhiyun 
79*4882a593Smuzhiyun 	/* now proceed to make the upcall */
80*4882a593Smuzhiyun 	cnp = ITOC(target_inode);
81*4882a593Smuzhiyun 
82*4882a593Smuzhiyun 	error = venus_pioctl(inode->i_sb, &(cnp->c_fid), cmd, &data);
83*4882a593Smuzhiyun out:
84*4882a593Smuzhiyun 	path_put(&path);
85*4882a593Smuzhiyun 	return error;
86*4882a593Smuzhiyun }
87