1/*
2 *   fs/cifs/ioctl.c
3 *
4 *   vfs operations that deal with io control
5 *
6 *   Copyright (C) International Business Machines  Corp., 2005,2013
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 <linux/file.h>
26#include <linux/mount.h>
27#include <linux/mm.h>
28#include <linux/pagemap.h>
29#include "cifspdu.h"
30#include "cifsglob.h"
31#include "cifsproto.h"
32#include "cifs_debug.h"
33#include "cifsfs.h"
34
35#define CIFS_IOCTL_MAGIC	0xCF
36#define CIFS_IOC_COPYCHUNK_FILE	_IOW(CIFS_IOCTL_MAGIC, 3, int)
37
38static long cifs_ioctl_clone(unsigned int xid, struct file *dst_file,
39			unsigned long srcfd, u64 off, u64 len, u64 destoff)
40{
41	int rc;
42	struct cifsFileInfo *smb_file_target = dst_file->private_data;
43	struct inode *target_inode = file_inode(dst_file);
44	struct cifs_tcon *target_tcon;
45	struct fd src_file;
46	struct cifsFileInfo *smb_file_src;
47	struct inode *src_inode;
48	struct cifs_tcon *src_tcon;
49
50	cifs_dbg(FYI, "ioctl clone range\n");
51	/* the destination must be opened for writing */
52	if (!(dst_file->f_mode & FMODE_WRITE)) {
53		cifs_dbg(FYI, "file target not open for write\n");
54		return -EINVAL;
55	}
56
57	/* check if target volume is readonly and take reference */
58	rc = mnt_want_write_file(dst_file);
59	if (rc) {
60		cifs_dbg(FYI, "mnt_want_write failed with rc %d\n", rc);
61		return rc;
62	}
63
64	src_file = fdget(srcfd);
65	if (!src_file.file) {
66		rc = -EBADF;
67		goto out_drop_write;
68	}
69
70	if (src_file.file->f_op->unlocked_ioctl != cifs_ioctl) {
71		rc = -EBADF;
72		cifs_dbg(VFS, "src file seems to be from a different filesystem type\n");
73		goto out_fput;
74	}
75
76	if ((!src_file.file->private_data) || (!dst_file->private_data)) {
77		rc = -EBADF;
78		cifs_dbg(VFS, "missing cifsFileInfo on copy range src file\n");
79		goto out_fput;
80	}
81
82	rc = -EXDEV;
83	smb_file_target = dst_file->private_data;
84	smb_file_src = src_file.file->private_data;
85	src_tcon = tlink_tcon(smb_file_src->tlink);
86	target_tcon = tlink_tcon(smb_file_target->tlink);
87
88	/* check if source and target are on same tree connection */
89	if (src_tcon != target_tcon) {
90		cifs_dbg(VFS, "file copy src and target on different volume\n");
91		goto out_fput;
92	}
93
94	src_inode = file_inode(src_file.file);
95	rc = -EINVAL;
96	if (S_ISDIR(src_inode->i_mode))
97		goto out_fput;
98
99	/*
100	 * Note: cifs case is easier than btrfs since server responsible for
101	 * checks for proper open modes and file type and if it wants
102	 * server could even support copy of range where source = target
103	 */
104	lock_two_nondirectories(target_inode, src_inode);
105
106	/* determine range to clone */
107	rc = -EINVAL;
108	if (off + len > src_inode->i_size || off + len < off)
109		goto out_unlock;
110	if (len == 0)
111		len = src_inode->i_size - off;
112
113	cifs_dbg(FYI, "about to flush pages\n");
114	/* should we flush first and last page first */
115	truncate_inode_pages_range(&target_inode->i_data, destoff,
116				   PAGE_CACHE_ALIGN(destoff + len)-1);
117
118	if (target_tcon->ses->server->ops->clone_range)
119		rc = target_tcon->ses->server->ops->clone_range(xid,
120			smb_file_src, smb_file_target, off, len, destoff);
121
122	/* force revalidate of size and timestamps of target file now
123	   that target is updated on the server */
124	CIFS_I(target_inode)->time = 0;
125out_unlock:
126	/* although unlocking in the reverse order from locking is not
127	   strictly necessary here it is a little cleaner to be consistent */
128	unlock_two_nondirectories(src_inode, target_inode);
129out_fput:
130	fdput(src_file);
131out_drop_write:
132	mnt_drop_write_file(dst_file);
133	return rc;
134}
135
136long cifs_ioctl(struct file *filep, unsigned int command, unsigned long arg)
137{
138	struct inode *inode = file_inode(filep);
139	int rc = -ENOTTY; /* strange error - but the precedent */
140	unsigned int xid;
141	struct cifs_sb_info *cifs_sb;
142	struct cifsFileInfo *pSMBFile = filep->private_data;
143	struct cifs_tcon *tcon;
144	__u64	ExtAttrBits = 0;
145	__u64   caps;
146
147	xid = get_xid();
148
149	cifs_dbg(FYI, "ioctl file %p  cmd %u  arg %lu\n", filep, command, arg);
150
151	cifs_sb = CIFS_SB(inode->i_sb);
152
153	switch (command) {
154		case FS_IOC_GETFLAGS:
155			if (pSMBFile == NULL)
156				break;
157			tcon = tlink_tcon(pSMBFile->tlink);
158			caps = le64_to_cpu(tcon->fsUnixInfo.Capability);
159#ifdef CONFIG_CIFS_POSIX
160			if (CIFS_UNIX_EXTATTR_CAP & caps) {
161				__u64	ExtAttrMask = 0;
162				rc = CIFSGetExtAttr(xid, tcon,
163						    pSMBFile->fid.netfid,
164						    &ExtAttrBits, &ExtAttrMask);
165				if (rc == 0)
166					rc = put_user(ExtAttrBits &
167						FS_FL_USER_VISIBLE,
168						(int __user *)arg);
169				if (rc != EOPNOTSUPP)
170					break;
171			}
172#endif /* CONFIG_CIFS_POSIX */
173			rc = 0;
174			if (CIFS_I(inode)->cifsAttrs & ATTR_COMPRESSED) {
175				/* add in the compressed bit */
176				ExtAttrBits = FS_COMPR_FL;
177				rc = put_user(ExtAttrBits & FS_FL_USER_VISIBLE,
178					      (int __user *)arg);
179			}
180			break;
181		case FS_IOC_SETFLAGS:
182			if (pSMBFile == NULL)
183				break;
184			tcon = tlink_tcon(pSMBFile->tlink);
185			caps = le64_to_cpu(tcon->fsUnixInfo.Capability);
186
187			if (get_user(ExtAttrBits, (int __user *)arg)) {
188				rc = -EFAULT;
189				break;
190			}
191
192			/*
193			 * if (CIFS_UNIX_EXTATTR_CAP & caps)
194			 *	rc = CIFSSetExtAttr(xid, tcon,
195			 *		       pSMBFile->fid.netfid,
196			 *		       extAttrBits,
197			 *		       &ExtAttrMask);
198			 * if (rc != EOPNOTSUPP)
199			 *	break;
200			 */
201
202			/* Currently only flag we can set is compressed flag */
203			if ((ExtAttrBits & FS_COMPR_FL) == 0)
204				break;
205
206			/* Try to set compress flag */
207			if (tcon->ses->server->ops->set_compression) {
208				rc = tcon->ses->server->ops->set_compression(
209							xid, tcon, pSMBFile);
210				cifs_dbg(FYI, "set compress flag rc %d\n", rc);
211			}
212			break;
213		case CIFS_IOC_COPYCHUNK_FILE:
214			rc = cifs_ioctl_clone(xid, filep, arg, 0, 0, 0);
215			break;
216		default:
217			cifs_dbg(FYI, "unsupported ioctl\n");
218			break;
219	}
220
221	free_xid(xid);
222	return rc;
223}
224