cifs: don't allow mmap'ed pages to be dirtied while under writeback (try #3)
[pandora-kernel.git] / fs / cifs / ioctl.c
1 /*
2  *   fs/cifs/ioctl.c
3  *
4  *   vfs operations that deal with io control
5  *
6  *   Copyright (C) International Business Machines  Corp., 2005,2007
7  *   Author(s): Steve French (sfrench@us.ibm.com)
8  *
9  *   This library is free software; you can redistribute it and/or modify
10  *   it under the terms of the GNU Lesser General Public License as published
11  *   by the Free Software Foundation; either version 2.1 of the License, or
12  *   (at your option) any later version.
13  *
14  *   This library is distributed in the hope that it will be useful,
15  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
16  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
17  *   the GNU Lesser General Public License for more details.
18  *
19  *   You should have received a copy of the GNU Lesser General Public License
20  *   along with this library; if not, write to the Free Software
21  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
22  */
23
24 #include <linux/fs.h>
25 #include "cifspdu.h"
26 #include "cifsglob.h"
27 #include "cifsproto.h"
28 #include "cifs_debug.h"
29 #include "cifsfs.h"
30
31 #define CIFS_IOC_CHECKUMOUNT _IO(0xCF, 2)
32
33 long cifs_ioctl(struct file *filep, unsigned int command, unsigned long arg)
34 {
35         struct inode *inode = filep->f_dentry->d_inode;
36         int rc = -ENOTTY; /* strange error - but the precedent */
37         int xid;
38         struct cifs_sb_info *cifs_sb;
39 #ifdef CONFIG_CIFS_POSIX
40         struct cifsFileInfo *pSMBFile = filep->private_data;
41         struct cifsTconInfo *tcon;
42         __u64   ExtAttrBits = 0;
43         __u64   ExtAttrMask = 0;
44         __u64   caps;
45 #endif /* CONFIG_CIFS_POSIX */
46
47         xid = GetXid();
48
49         cFYI(1, "ioctl file %p  cmd %u  arg %lu", filep, command, arg);
50
51         cifs_sb = CIFS_SB(inode->i_sb);
52
53         switch (command) {
54                 case CIFS_IOC_CHECKUMOUNT:
55                         cFYI(1, "User unmount attempted");
56                         if (cifs_sb->mnt_uid == current_uid())
57                                 rc = 0;
58                         else {
59                                 rc = -EACCES;
60                                 cFYI(1, "uids do not match");
61                         }
62                         break;
63 #ifdef CONFIG_CIFS_POSIX
64                 case FS_IOC_GETFLAGS:
65                         if (pSMBFile == NULL)
66                                 break;
67                         tcon = tlink_tcon(pSMBFile->tlink);
68                         caps = le64_to_cpu(tcon->fsUnixInfo.Capability);
69                         if (CIFS_UNIX_EXTATTR_CAP & caps) {
70                                 rc = CIFSGetExtAttr(xid, tcon, pSMBFile->netfid,
71                                         &ExtAttrBits, &ExtAttrMask);
72                                 if (rc == 0)
73                                         rc = put_user(ExtAttrBits &
74                                                 FS_FL_USER_VISIBLE,
75                                                 (int __user *)arg);
76                         }
77                         break;
78
79                 case FS_IOC_SETFLAGS:
80                         if (pSMBFile == NULL)
81                                 break;
82                         tcon = tlink_tcon(pSMBFile->tlink);
83                         caps = le64_to_cpu(tcon->fsUnixInfo.Capability);
84                         if (CIFS_UNIX_EXTATTR_CAP & caps) {
85                                 if (get_user(ExtAttrBits, (int __user *)arg)) {
86                                         rc = -EFAULT;
87                                         break;
88                                 }
89                                 /* rc= CIFSGetExtAttr(xid,tcon,pSMBFile->netfid,
90                                         extAttrBits, &ExtAttrMask);*/
91                         }
92                         cFYI(1, "set flags not implemented yet");
93                         break;
94 #endif /* CONFIG_CIFS_POSIX */
95                 default:
96                         cFYI(1, "unsupported ioctl");
97                         break;
98         }
99
100         FreeXid(xid);
101         return rc;
102 }