xref: /openbmc/linux/fs/coda/pioctl.c (revision 367b8112)
1 /*
2  * Pioctl operations for Coda.
3  * Original version: (C) 1996 Peter Braam
4  * Rewritten for Linux 2.1: (C) 1997 Carnegie Mellon University
5  *
6  * Carnegie Mellon encourages users of this code to contribute improvements
7  * to the Coda project. Contact Peter Braam <coda@cs.cmu.edu>.
8  */
9 
10 #include <linux/types.h>
11 #include <linux/kernel.h>
12 #include <linux/time.h>
13 #include <linux/fs.h>
14 #include <linux/stat.h>
15 #include <linux/errno.h>
16 #include <linux/string.h>
17 #include <linux/namei.h>
18 #include <linux/module.h>
19 #include <asm/uaccess.h>
20 
21 #include <linux/coda.h>
22 #include <linux/coda_linux.h>
23 #include <linux/coda_fs_i.h>
24 #include <linux/coda_psdev.h>
25 
26 /* pioctl ops */
27 static int coda_ioctl_permission(struct inode *inode, int mask);
28 static int coda_pioctl(struct inode * inode, struct file * filp,
29                        unsigned int cmd, unsigned long user_data);
30 
31 /* exported from this file */
32 const struct inode_operations coda_ioctl_inode_operations =
33 {
34 	.permission	= coda_ioctl_permission,
35 	.setattr	= coda_setattr,
36 };
37 
38 const struct file_operations coda_ioctl_operations = {
39 	.owner		= THIS_MODULE,
40 	.ioctl		= coda_pioctl,
41 };
42 
43 /* the coda pioctl inode ops */
44 static int coda_ioctl_permission(struct inode *inode, int mask)
45 {
46 	return (mask & MAY_EXEC) ? -EACCES : 0;
47 }
48 
49 static int coda_pioctl(struct inode * inode, struct file * filp,
50                        unsigned int cmd, unsigned long user_data)
51 {
52 	struct path path;
53         int error;
54 	struct PioctlData data;
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         /*
64          * Look up the pathname. Note that the pathname is in
65          * user memory, and namei takes care of this
66          */
67         if (data.follow) {
68                 error = user_path(data.path, &path);
69 	} else {
70 	        error = user_lpath(data.path, &path);
71 	}
72 
73 	if ( error ) {
74 		return error;
75         } else {
76 		target_inode = path.dentry->d_inode;
77 	}
78 
79 	/* return if it is not a Coda inode */
80 	if ( target_inode->i_sb != inode->i_sb ) {
81 		path_put(&path);
82 	        return  -EINVAL;
83 	}
84 
85 	/* now proceed to make the upcall */
86         cnp = ITOC(target_inode);
87 
88 	error = venus_pioctl(inode->i_sb, &(cnp->c_fid), cmd, &data);
89 
90 	path_put(&path);
91         return error;
92 }
93 
94