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Linux kernel mirror (for testing)
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kernel
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linux
1/*
2 * fs/cifs/smb2file.c
3 *
4 * Copyright (C) International Business Machines Corp., 2002, 2011
5 * Author(s): Steve French (sfrench@us.ibm.com),
6 * Pavel Shilovsky ((pshilovsky@samba.org) 2012
7 *
8 * This library is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU Lesser General Public License as published
10 * by the Free Software Foundation; either version 2.1 of the License, or
11 * (at your option) any later version.
12 *
13 * This library is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
16 * the GNU Lesser General Public License for more details.
17 *
18 * You should have received a copy of the GNU Lesser General Public License
19 * along with this library; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
21 */
22#include <linux/fs.h>
23#include <linux/stat.h>
24#include <linux/slab.h>
25#include <linux/pagemap.h>
26#include <asm/div64.h>
27#include "cifsfs.h"
28#include "cifspdu.h"
29#include "cifsglob.h"
30#include "cifsproto.h"
31#include "cifs_debug.h"
32#include "cifs_fs_sb.h"
33#include "cifs_unicode.h"
34#include "fscache.h"
35#include "smb2proto.h"
36
37int
38smb2_open_file(const unsigned int xid, struct cifs_open_parms *oparms,
39 __u32 *oplock, FILE_ALL_INFO *buf)
40{
41 int rc;
42 __le16 *smb2_path;
43 struct smb2_file_all_info *smb2_data = NULL;
44 __u8 smb2_oplock;
45 struct cifs_fid *fid = oparms->fid;
46 struct network_resiliency_req nr_ioctl_req;
47
48 smb2_path = cifs_convert_path_to_utf16(oparms->path, oparms->cifs_sb);
49 if (smb2_path == NULL) {
50 rc = -ENOMEM;
51 goto out;
52 }
53
54 smb2_data = kzalloc(sizeof(struct smb2_file_all_info) + PATH_MAX * 2,
55 GFP_KERNEL);
56 if (smb2_data == NULL) {
57 rc = -ENOMEM;
58 goto out;
59 }
60
61 oparms->desired_access |= FILE_READ_ATTRIBUTES;
62 smb2_oplock = SMB2_OPLOCK_LEVEL_BATCH;
63
64 rc = SMB2_open(xid, oparms, smb2_path, &smb2_oplock, smb2_data, NULL,
65 NULL);
66 if (rc)
67 goto out;
68
69
70 if (oparms->tcon->use_resilient) {
71 /* default timeout is 0, servers pick default (120 seconds) */
72 nr_ioctl_req.Timeout =
73 cpu_to_le32(oparms->tcon->handle_timeout);
74 nr_ioctl_req.Reserved = 0;
75 rc = SMB2_ioctl(xid, oparms->tcon, fid->persistent_fid,
76 fid->volatile_fid, FSCTL_LMR_REQUEST_RESILIENCY,
77 true /* is_fsctl */,
78 (char *)&nr_ioctl_req, sizeof(nr_ioctl_req),
79 CIFSMaxBufSize, NULL, NULL /* no return info */);
80 if (rc == -EOPNOTSUPP) {
81 cifs_dbg(VFS,
82 "resiliency not supported by server, disabling\n");
83 oparms->tcon->use_resilient = false;
84 } else if (rc)
85 cifs_dbg(FYI, "error %d setting resiliency\n", rc);
86
87 rc = 0;
88 }
89
90 if (buf) {
91 /* if open response does not have IndexNumber field - get it */
92 if (smb2_data->IndexNumber == 0) {
93 rc = SMB2_get_srv_num(xid, oparms->tcon,
94 fid->persistent_fid,
95 fid->volatile_fid,
96 &smb2_data->IndexNumber);
97 if (rc) {
98 /*
99 * let get_inode_info disable server inode
100 * numbers
101 */
102 smb2_data->IndexNumber = 0;
103 rc = 0;
104 }
105 }
106 move_smb2_info_to_cifs(buf, smb2_data);
107 }
108
109 *oplock = smb2_oplock;
110out:
111 kfree(smb2_data);
112 kfree(smb2_path);
113 return rc;
114}
115
116int
117smb2_unlock_range(struct cifsFileInfo *cfile, struct file_lock *flock,
118 const unsigned int xid)
119{
120 int rc = 0, stored_rc;
121 unsigned int max_num, num = 0, max_buf;
122 struct smb2_lock_element *buf, *cur;
123 struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
124 struct cifsInodeInfo *cinode = CIFS_I(d_inode(cfile->dentry));
125 struct cifsLockInfo *li, *tmp;
126 __u64 length = 1 + flock->fl_end - flock->fl_start;
127 struct list_head tmp_llist;
128
129 INIT_LIST_HEAD(&tmp_llist);
130
131 /*
132 * Accessing maxBuf is racy with cifs_reconnect - need to store value
133 * and check it before using.
134 */
135 max_buf = tcon->ses->server->maxBuf;
136 if (max_buf < sizeof(struct smb2_lock_element))
137 return -EINVAL;
138
139 BUILD_BUG_ON(sizeof(struct smb2_lock_element) > PAGE_SIZE);
140 max_buf = min_t(unsigned int, max_buf, PAGE_SIZE);
141 max_num = max_buf / sizeof(struct smb2_lock_element);
142 buf = kcalloc(max_num, sizeof(struct smb2_lock_element), GFP_KERNEL);
143 if (!buf)
144 return -ENOMEM;
145
146 cur = buf;
147
148 cifs_down_write(&cinode->lock_sem);
149 list_for_each_entry_safe(li, tmp, &cfile->llist->locks, llist) {
150 if (flock->fl_start > li->offset ||
151 (flock->fl_start + length) <
152 (li->offset + li->length))
153 continue;
154 if (current->tgid != li->pid)
155 continue;
156 if (cinode->can_cache_brlcks) {
157 /*
158 * We can cache brlock requests - simply remove a lock
159 * from the file's list.
160 */
161 list_del(&li->llist);
162 cifs_del_lock_waiters(li);
163 kfree(li);
164 continue;
165 }
166 cur->Length = cpu_to_le64(li->length);
167 cur->Offset = cpu_to_le64(li->offset);
168 cur->Flags = cpu_to_le32(SMB2_LOCKFLAG_UNLOCK);
169 /*
170 * We need to save a lock here to let us add it again to the
171 * file's list if the unlock range request fails on the server.
172 */
173 list_move(&li->llist, &tmp_llist);
174 if (++num == max_num) {
175 stored_rc = smb2_lockv(xid, tcon,
176 cfile->fid.persistent_fid,
177 cfile->fid.volatile_fid,
178 current->tgid, num, buf);
179 if (stored_rc) {
180 /*
181 * We failed on the unlock range request - add
182 * all locks from the tmp list to the head of
183 * the file's list.
184 */
185 cifs_move_llist(&tmp_llist,
186 &cfile->llist->locks);
187 rc = stored_rc;
188 } else
189 /*
190 * The unlock range request succeed - free the
191 * tmp list.
192 */
193 cifs_free_llist(&tmp_llist);
194 cur = buf;
195 num = 0;
196 } else
197 cur++;
198 }
199 if (num) {
200 stored_rc = smb2_lockv(xid, tcon, cfile->fid.persistent_fid,
201 cfile->fid.volatile_fid, current->tgid,
202 num, buf);
203 if (stored_rc) {
204 cifs_move_llist(&tmp_llist, &cfile->llist->locks);
205 rc = stored_rc;
206 } else
207 cifs_free_llist(&tmp_llist);
208 }
209 up_write(&cinode->lock_sem);
210
211 kfree(buf);
212 return rc;
213}
214
215static int
216smb2_push_mand_fdlocks(struct cifs_fid_locks *fdlocks, const unsigned int xid,
217 struct smb2_lock_element *buf, unsigned int max_num)
218{
219 int rc = 0, stored_rc;
220 struct cifsFileInfo *cfile = fdlocks->cfile;
221 struct cifsLockInfo *li;
222 unsigned int num = 0;
223 struct smb2_lock_element *cur = buf;
224 struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
225
226 list_for_each_entry(li, &fdlocks->locks, llist) {
227 cur->Length = cpu_to_le64(li->length);
228 cur->Offset = cpu_to_le64(li->offset);
229 cur->Flags = cpu_to_le32(li->type |
230 SMB2_LOCKFLAG_FAIL_IMMEDIATELY);
231 if (++num == max_num) {
232 stored_rc = smb2_lockv(xid, tcon,
233 cfile->fid.persistent_fid,
234 cfile->fid.volatile_fid,
235 current->tgid, num, buf);
236 if (stored_rc)
237 rc = stored_rc;
238 cur = buf;
239 num = 0;
240 } else
241 cur++;
242 }
243 if (num) {
244 stored_rc = smb2_lockv(xid, tcon,
245 cfile->fid.persistent_fid,
246 cfile->fid.volatile_fid,
247 current->tgid, num, buf);
248 if (stored_rc)
249 rc = stored_rc;
250 }
251
252 return rc;
253}
254
255int
256smb2_push_mandatory_locks(struct cifsFileInfo *cfile)
257{
258 int rc = 0, stored_rc;
259 unsigned int xid;
260 unsigned int max_num, max_buf;
261 struct smb2_lock_element *buf;
262 struct cifsInodeInfo *cinode = CIFS_I(d_inode(cfile->dentry));
263 struct cifs_fid_locks *fdlocks;
264
265 xid = get_xid();
266
267 /*
268 * Accessing maxBuf is racy with cifs_reconnect - need to store value
269 * and check it for zero before using.
270 */
271 max_buf = tlink_tcon(cfile->tlink)->ses->server->maxBuf;
272 if (max_buf < sizeof(struct smb2_lock_element)) {
273 free_xid(xid);
274 return -EINVAL;
275 }
276
277 BUILD_BUG_ON(sizeof(struct smb2_lock_element) > PAGE_SIZE);
278 max_buf = min_t(unsigned int, max_buf, PAGE_SIZE);
279 max_num = max_buf / sizeof(struct smb2_lock_element);
280 buf = kcalloc(max_num, sizeof(struct smb2_lock_element), GFP_KERNEL);
281 if (!buf) {
282 free_xid(xid);
283 return -ENOMEM;
284 }
285
286 list_for_each_entry(fdlocks, &cinode->llist, llist) {
287 stored_rc = smb2_push_mand_fdlocks(fdlocks, xid, buf, max_num);
288 if (stored_rc)
289 rc = stored_rc;
290 }
291
292 kfree(buf);
293 free_xid(xid);
294 return rc;
295}