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 #include "cifs_ioctl.h"
35 #include <linux/btrfs.h>
36 
cifs_ioctl_clone(unsigned int xid,struct file * dst_file,unsigned long srcfd,u64 off,u64 len,u64 destoff,bool dup_extents)37 static long cifs_ioctl_clone(unsigned int xid, struct file *dst_file,
38 			unsigned long srcfd, u64 off, u64 len, u64 destoff,
39 			bool dup_extents)
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 source and target on same server (or volume if dup_extents) */
89 	if (dup_extents && (src_tcon != target_tcon)) {
90 		cifs_dbg(VFS, "source and target of copy not on same share\n");
91 		goto out_fput;
92 	}
93 
94 	if (!dup_extents && (src_tcon->ses != target_tcon->ses)) {
95 		cifs_dbg(VFS, "source and target of copy not on same server\n");
96 		goto out_fput;
97 	}
98 
99 	src_inode = file_inode(src_file.file);
100 	rc = -EINVAL;
101 	if (S_ISDIR(src_inode->i_mode))
102 		goto out_fput;
103 
104 	/*
105 	 * Note: cifs case is easier than btrfs since server responsible for
106 	 * checks for proper open modes and file type and if it wants
107 	 * server could even support copy of range where source = target
108 	 */
109 	lock_two_nondirectories(target_inode, src_inode);
110 
111 	/* determine range to clone */
112 	rc = -EINVAL;
113 	if (off + len > src_inode->i_size || off + len < off)
114 		goto out_unlock;
115 	if (len == 0)
116 		len = src_inode->i_size - off;
117 
118 	cifs_dbg(FYI, "about to flush pages\n");
119 	/* should we flush first and last page first */
120 	truncate_inode_pages_range(&target_inode->i_data, destoff,
121 				   PAGE_CACHE_ALIGN(destoff + len)-1);
122 
123 	if (dup_extents && target_tcon->ses->server->ops->duplicate_extents)
124 		rc = target_tcon->ses->server->ops->duplicate_extents(xid,
125 			smb_file_src, smb_file_target, off, len, destoff);
126 	else if (!dup_extents && target_tcon->ses->server->ops->clone_range)
127 		rc = target_tcon->ses->server->ops->clone_range(xid,
128 			smb_file_src, smb_file_target, off, len, destoff);
129 	else
130 		rc = -EOPNOTSUPP;
131 
132 	/* force revalidate of size and timestamps of target file now
133 	   that target is updated on the server */
134 	CIFS_I(target_inode)->time = 0;
135 out_unlock:
136 	/* although unlocking in the reverse order from locking is not
137 	   strictly necessary here it is a little cleaner to be consistent */
138 	unlock_two_nondirectories(src_inode, target_inode);
139 out_fput:
140 	fdput(src_file);
141 out_drop_write:
142 	mnt_drop_write_file(dst_file);
143 	return rc;
144 }
145 
smb_mnt_get_fsinfo(unsigned int xid,struct cifs_tcon * tcon,void __user * arg)146 static long smb_mnt_get_fsinfo(unsigned int xid, struct cifs_tcon *tcon,
147 				void __user *arg)
148 {
149 	int rc = 0;
150 	struct smb_mnt_fs_info *fsinf;
151 
152 	fsinf = kzalloc(sizeof(struct smb_mnt_fs_info), GFP_KERNEL);
153 	if (fsinf == NULL)
154 		return -ENOMEM;
155 
156 	fsinf->version = 1;
157 	fsinf->protocol_id = tcon->ses->server->vals->protocol_id;
158 	fsinf->device_characteristics =
159 			le32_to_cpu(tcon->fsDevInfo.DeviceCharacteristics);
160 	fsinf->device_type = le32_to_cpu(tcon->fsDevInfo.DeviceType);
161 	fsinf->fs_attributes = le32_to_cpu(tcon->fsAttrInfo.Attributes);
162 	fsinf->max_path_component =
163 		le32_to_cpu(tcon->fsAttrInfo.MaxPathNameComponentLength);
164 #ifdef CONFIG_CIFS_SMB2
165 	fsinf->vol_serial_number = tcon->vol_serial_number;
166 	fsinf->vol_create_time = le64_to_cpu(tcon->vol_create_time);
167 	fsinf->share_flags = tcon->share_flags;
168 	fsinf->share_caps = le32_to_cpu(tcon->capabilities);
169 	fsinf->sector_flags = tcon->ss_flags;
170 	fsinf->optimal_sector_size = tcon->perf_sector_size;
171 	fsinf->max_bytes_chunk = tcon->max_bytes_chunk;
172 	fsinf->maximal_access = tcon->maximal_access;
173 #endif /* SMB2 */
174 	fsinf->cifs_posix_caps = le64_to_cpu(tcon->fsUnixInfo.Capability);
175 
176 	if (copy_to_user(arg, fsinf, sizeof(struct smb_mnt_fs_info)))
177 		rc = -EFAULT;
178 
179 	kfree(fsinf);
180 	return rc;
181 }
182 
cifs_ioctl(struct file * filep,unsigned int command,unsigned long arg)183 long cifs_ioctl(struct file *filep, unsigned int command, unsigned long arg)
184 {
185 	struct inode *inode = file_inode(filep);
186 	int rc = -ENOTTY; /* strange error - but the precedent */
187 	unsigned int xid;
188 	struct cifs_sb_info *cifs_sb;
189 	struct cifsFileInfo *pSMBFile = filep->private_data;
190 	struct cifs_tcon *tcon;
191 	__u64	ExtAttrBits = 0;
192 	__u64   caps;
193 
194 	xid = get_xid();
195 
196 	cifs_sb = CIFS_SB(inode->i_sb);
197 
198 	switch (command) {
199 		case FS_IOC_GETFLAGS:
200 			if (pSMBFile == NULL)
201 				break;
202 			tcon = tlink_tcon(pSMBFile->tlink);
203 			caps = le64_to_cpu(tcon->fsUnixInfo.Capability);
204 #ifdef CONFIG_CIFS_POSIX
205 			if (CIFS_UNIX_EXTATTR_CAP & caps) {
206 				__u64	ExtAttrMask = 0;
207 				rc = CIFSGetExtAttr(xid, tcon,
208 						    pSMBFile->fid.netfid,
209 						    &ExtAttrBits, &ExtAttrMask);
210 				if (rc == 0)
211 					rc = put_user(ExtAttrBits &
212 						FS_FL_USER_VISIBLE,
213 						(int __user *)arg);
214 				if (rc != EOPNOTSUPP)
215 					break;
216 			}
217 #endif /* CONFIG_CIFS_POSIX */
218 			rc = 0;
219 			if (CIFS_I(inode)->cifsAttrs & ATTR_COMPRESSED) {
220 				/* add in the compressed bit */
221 				ExtAttrBits = FS_COMPR_FL;
222 				rc = put_user(ExtAttrBits & FS_FL_USER_VISIBLE,
223 					      (int __user *)arg);
224 			}
225 			break;
226 		case FS_IOC_SETFLAGS:
227 			if (pSMBFile == NULL)
228 				break;
229 			tcon = tlink_tcon(pSMBFile->tlink);
230 			caps = le64_to_cpu(tcon->fsUnixInfo.Capability);
231 
232 			if (get_user(ExtAttrBits, (int __user *)arg)) {
233 				rc = -EFAULT;
234 				break;
235 			}
236 
237 			/*
238 			 * if (CIFS_UNIX_EXTATTR_CAP & caps)
239 			 *	rc = CIFSSetExtAttr(xid, tcon,
240 			 *		       pSMBFile->fid.netfid,
241 			 *		       extAttrBits,
242 			 *		       &ExtAttrMask);
243 			 * if (rc != EOPNOTSUPP)
244 			 *	break;
245 			 */
246 
247 			/* Currently only flag we can set is compressed flag */
248 			if ((ExtAttrBits & FS_COMPR_FL) == 0)
249 				break;
250 
251 			/* Try to set compress flag */
252 			if (tcon->ses->server->ops->set_compression) {
253 				rc = tcon->ses->server->ops->set_compression(
254 							xid, tcon, pSMBFile);
255 				cifs_dbg(FYI, "set compress flag rc %d\n", rc);
256 			}
257 			break;
258 		case CIFS_IOC_COPYCHUNK_FILE:
259 			rc = cifs_ioctl_clone(xid, filep, arg, 0, 0, 0, false);
260 			break;
261 		case BTRFS_IOC_CLONE:
262 			rc = cifs_ioctl_clone(xid, filep, arg, 0, 0, 0, true);
263 			break;
264 		case CIFS_IOC_SET_INTEGRITY:
265 			if (pSMBFile == NULL)
266 				break;
267 			tcon = tlink_tcon(pSMBFile->tlink);
268 			if (tcon->ses->server->ops->set_integrity)
269 				rc = tcon->ses->server->ops->set_integrity(xid,
270 						tcon, pSMBFile);
271 			else
272 				rc = -EOPNOTSUPP;
273 			break;
274 		case CIFS_IOC_GET_MNT_INFO:
275 			tcon = tlink_tcon(pSMBFile->tlink);
276 			rc = smb_mnt_get_fsinfo(xid, tcon, (void __user *)arg);
277 			break;
278 		default:
279 			cifs_dbg(FYI, "unsupported ioctl\n");
280 			break;
281 	}
282 
283 	free_xid(xid);
284 	return rc;
285 }
286