Root/fs/coda/pioctl.c

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_psdev.h>
23
24#include "coda_linux.h"
25
26/* pioctl ops */
27static int coda_ioctl_permission(struct inode *inode, int mask, unsigned int flags);
28static long coda_pioctl(struct file *filp, unsigned int cmd,
29            unsigned long user_data);
30
31/* exported from this file */
32const struct inode_operations coda_ioctl_inode_operations = {
33    .permission = coda_ioctl_permission,
34    .setattr = coda_setattr,
35};
36
37const struct file_operations coda_ioctl_operations = {
38    .owner = THIS_MODULE,
39    .unlocked_ioctl = coda_pioctl,
40    .llseek = noop_llseek,
41};
42
43/* the coda pioctl inode ops */
44static int coda_ioctl_permission(struct inode *inode, int mask, unsigned int flags)
45{
46    return (mask & MAY_EXEC) ? -EACCES : 0;
47}
48
49static long coda_pioctl(struct file *filp, unsigned int cmd,
50            unsigned long user_data)
51{
52    struct path path;
53    int error;
54    struct PioctlData data;
55    struct inode *inode = filp->f_dentry->d_inode;
56    struct inode *target_inode = NULL;
57    struct coda_inode_info *cnp;
58
59    /* get the Pioctl data arguments from user space */
60    if (copy_from_user(&data, (void __user *)user_data, sizeof(data)))
61        return -EINVAL;
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    if (error)
73        return error;
74
75    target_inode = path.dentry->d_inode;
76
77    /* return if it is not a Coda inode */
78    if (target_inode->i_sb != inode->i_sb) {
79        error = -EINVAL;
80        goto out;
81    }
82
83    /* now proceed to make the upcall */
84    cnp = ITOC(target_inode);
85
86    error = venus_pioctl(inode->i_sb, &(cnp->c_fid), cmd, &data);
87out:
88    path_put(&path);
89    return error;
90}
91

Archive Download this file



interactive