CIFS: Add writepage support for SMB2
[cascardo/linux.git] / fs / cifs / smb2ops.c
1 /*
2  *  SMB2 version specific operations
3  *
4  *  Copyright (c) 2012, Jeff Layton <jlayton@redhat.com>
5  *
6  *  This library is free software; you can redistribute it and/or modify
7  *  it under the terms of the GNU General Public License v2 as published
8  *  by the Free Software Foundation.
9  *
10  *  This library is distributed in the hope that it will be useful,
11  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
12  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
13  *  the GNU Lesser General Public License for more details.
14  *
15  *  You should have received a copy of the GNU Lesser General Public License
16  *  along with this library; if not, write to the Free Software
17  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18  */
19
20 #include <linux/pagemap.h>
21 #include "cifsglob.h"
22 #include "smb2pdu.h"
23 #include "smb2proto.h"
24 #include "cifsproto.h"
25 #include "cifs_debug.h"
26
27 static int
28 change_conf(struct TCP_Server_Info *server)
29 {
30         server->credits += server->echo_credits + server->oplock_credits;
31         server->oplock_credits = server->echo_credits = 0;
32         switch (server->credits) {
33         case 0:
34                 return -1;
35         case 1:
36                 server->echoes = false;
37                 server->oplocks = false;
38                 cERROR(1, "disabling echoes and oplocks");
39                 break;
40         case 2:
41                 server->echoes = true;
42                 server->oplocks = false;
43                 server->echo_credits = 1;
44                 cFYI(1, "disabling oplocks");
45                 break;
46         default:
47                 server->echoes = true;
48                 server->oplocks = true;
49                 server->echo_credits = 1;
50                 server->oplock_credits = 1;
51         }
52         server->credits -= server->echo_credits + server->oplock_credits;
53         return 0;
54 }
55
56 static void
57 smb2_add_credits(struct TCP_Server_Info *server, const unsigned int add,
58                  const int optype)
59 {
60         int *val, rc = 0;
61         spin_lock(&server->req_lock);
62         val = server->ops->get_credits_field(server, optype);
63         *val += add;
64         server->in_flight--;
65         if (server->in_flight == 0 && (optype & CIFS_OP_MASK) != CIFS_NEG_OP)
66                 rc = change_conf(server);
67         spin_unlock(&server->req_lock);
68         wake_up(&server->request_q);
69         if (rc)
70                 cifs_reconnect(server);
71 }
72
73 static void
74 smb2_set_credits(struct TCP_Server_Info *server, const int val)
75 {
76         spin_lock(&server->req_lock);
77         server->credits = val;
78         spin_unlock(&server->req_lock);
79 }
80
81 static int *
82 smb2_get_credits_field(struct TCP_Server_Info *server, const int optype)
83 {
84         switch (optype) {
85         case CIFS_ECHO_OP:
86                 return &server->echo_credits;
87         case CIFS_OBREAK_OP:
88                 return &server->oplock_credits;
89         default:
90                 return &server->credits;
91         }
92 }
93
94 static unsigned int
95 smb2_get_credits(struct mid_q_entry *mid)
96 {
97         return le16_to_cpu(((struct smb2_hdr *)mid->resp_buf)->CreditRequest);
98 }
99
100 static __u64
101 smb2_get_next_mid(struct TCP_Server_Info *server)
102 {
103         __u64 mid;
104         /* for SMB2 we need the current value */
105         spin_lock(&GlobalMid_Lock);
106         mid = server->CurrentMid++;
107         spin_unlock(&GlobalMid_Lock);
108         return mid;
109 }
110
111 static struct mid_q_entry *
112 smb2_find_mid(struct TCP_Server_Info *server, char *buf)
113 {
114         struct mid_q_entry *mid;
115         struct smb2_hdr *hdr = (struct smb2_hdr *)buf;
116
117         spin_lock(&GlobalMid_Lock);
118         list_for_each_entry(mid, &server->pending_mid_q, qhead) {
119                 if ((mid->mid == hdr->MessageId) &&
120                     (mid->mid_state == MID_REQUEST_SUBMITTED) &&
121                     (mid->command == hdr->Command)) {
122                         spin_unlock(&GlobalMid_Lock);
123                         return mid;
124                 }
125         }
126         spin_unlock(&GlobalMid_Lock);
127         return NULL;
128 }
129
130 static void
131 smb2_dump_detail(void *buf)
132 {
133 #ifdef CONFIG_CIFS_DEBUG2
134         struct smb2_hdr *smb = (struct smb2_hdr *)buf;
135
136         cERROR(1, "Cmd: %d Err: 0x%x Flags: 0x%x Mid: %llu Pid: %d",
137                   smb->Command, smb->Status, smb->Flags, smb->MessageId,
138                   smb->ProcessId);
139         cERROR(1, "smb buf %p len %u", smb, smb2_calc_size(smb));
140 #endif
141 }
142
143 static bool
144 smb2_need_neg(struct TCP_Server_Info *server)
145 {
146         return server->max_read == 0;
147 }
148
149 static int
150 smb2_negotiate(const unsigned int xid, struct cifs_ses *ses)
151 {
152         int rc;
153         ses->server->CurrentMid = 0;
154         rc = SMB2_negotiate(xid, ses);
155         /* BB we probably don't need to retry with modern servers */
156         if (rc == -EAGAIN)
157                 rc = -EHOSTDOWN;
158         return rc;
159 }
160
161 static unsigned int
162 smb2_negotiate_wsize(struct cifs_tcon *tcon, struct smb_vol *volume_info)
163 {
164         struct TCP_Server_Info *server = tcon->ses->server;
165         unsigned int wsize;
166
167         /* start with specified wsize, or default */
168         wsize = volume_info->wsize ? volume_info->wsize : CIFS_DEFAULT_IOSIZE;
169         wsize = min_t(unsigned int, wsize, server->max_write);
170         /*
171          * limit write size to 2 ** 16, because we don't support multicredit
172          * requests now.
173          */
174         wsize = min_t(unsigned int, wsize, 2 << 15);
175
176         /* limit to the amount that we can kmap at once */
177         wsize = min_t(unsigned int, wsize, CIFS_KMAP_SIZE_LIMIT);
178
179         return wsize;
180 }
181
182 static unsigned int
183 smb2_negotiate_rsize(struct cifs_tcon *tcon, struct smb_vol *volume_info)
184 {
185         struct TCP_Server_Info *server = tcon->ses->server;
186         unsigned int rsize;
187
188         /* start with specified rsize, or default */
189         rsize = volume_info->rsize ? volume_info->rsize : CIFS_DEFAULT_IOSIZE;
190         rsize = min_t(unsigned int, rsize, server->max_read);
191         /*
192          * limit write size to 2 ** 16, because we don't support multicredit
193          * requests now.
194          */
195         rsize = min_t(unsigned int, rsize, 2 << 15);
196
197         /* limit to the amount that we can kmap at once */
198         rsize = min_t(unsigned int, rsize, CIFS_KMAP_SIZE_LIMIT);
199
200         return rsize;
201 }
202
203 static int
204 smb2_is_path_accessible(const unsigned int xid, struct cifs_tcon *tcon,
205                         struct cifs_sb_info *cifs_sb, const char *full_path)
206 {
207         int rc;
208         __u64 persistent_fid, volatile_fid;
209         __le16 *utf16_path;
210
211         utf16_path = cifs_convert_path_to_utf16(full_path, cifs_sb);
212         if (!utf16_path)
213                 return -ENOMEM;
214
215         rc = SMB2_open(xid, tcon, utf16_path, &persistent_fid, &volatile_fid,
216                        FILE_READ_ATTRIBUTES, FILE_OPEN, 0, 0, NULL);
217         if (rc) {
218                 kfree(utf16_path);
219                 return rc;
220         }
221
222         rc = SMB2_close(xid, tcon, persistent_fid, volatile_fid);
223         kfree(utf16_path);
224         return rc;
225 }
226
227 static int
228 smb2_get_srv_inum(const unsigned int xid, struct cifs_tcon *tcon,
229                   struct cifs_sb_info *cifs_sb, const char *full_path,
230                   u64 *uniqueid, FILE_ALL_INFO *data)
231 {
232         *uniqueid = le64_to_cpu(data->IndexNumber);
233         return 0;
234 }
235
236 static int
237 smb2_query_file_info(const unsigned int xid, struct cifs_tcon *tcon,
238                      struct cifs_fid *fid, FILE_ALL_INFO *data)
239 {
240         int rc;
241         struct smb2_file_all_info *smb2_data;
242
243         smb2_data = kzalloc(sizeof(struct smb2_file_all_info) + MAX_NAME * 2,
244                             GFP_KERNEL);
245         if (smb2_data == NULL)
246                 return -ENOMEM;
247
248         rc = SMB2_query_info(xid, tcon, fid->persistent_fid, fid->volatile_fid,
249                              smb2_data);
250         if (!rc)
251                 move_smb2_info_to_cifs(data, smb2_data);
252         kfree(smb2_data);
253         return rc;
254 }
255
256 static char *
257 smb2_build_path_to_root(struct smb_vol *vol, struct cifs_sb_info *cifs_sb,
258                         struct cifs_tcon *tcon)
259 {
260         int pplen = vol->prepath ? strlen(vol->prepath) : 0;
261         char *full_path = NULL;
262
263         /* if no prefix path, simply set path to the root of share to "" */
264         if (pplen == 0) {
265                 full_path = kzalloc(2, GFP_KERNEL);
266                 return full_path;
267         }
268
269         cERROR(1, "prefixpath is not supported for SMB2 now");
270         return NULL;
271 }
272
273 static bool
274 smb2_can_echo(struct TCP_Server_Info *server)
275 {
276         return server->echoes;
277 }
278
279 static void
280 smb2_clear_stats(struct cifs_tcon *tcon)
281 {
282 #ifdef CONFIG_CIFS_STATS
283         int i;
284         for (i = 0; i < NUMBER_OF_SMB2_COMMANDS; i++) {
285                 atomic_set(&tcon->stats.smb2_stats.smb2_com_sent[i], 0);
286                 atomic_set(&tcon->stats.smb2_stats.smb2_com_failed[i], 0);
287         }
288 #endif
289 }
290
291 static void
292 smb2_print_stats(struct seq_file *m, struct cifs_tcon *tcon)
293 {
294 #ifdef CONFIG_CIFS_STATS
295         atomic_t *sent = tcon->stats.smb2_stats.smb2_com_sent;
296         atomic_t *failed = tcon->stats.smb2_stats.smb2_com_failed;
297         seq_printf(m, "\nNegotiates: %d sent %d failed",
298                    atomic_read(&sent[SMB2_NEGOTIATE_HE]),
299                    atomic_read(&failed[SMB2_NEGOTIATE_HE]));
300         seq_printf(m, "\nSessionSetups: %d sent %d failed",
301                    atomic_read(&sent[SMB2_SESSION_SETUP_HE]),
302                    atomic_read(&failed[SMB2_SESSION_SETUP_HE]));
303 #define SMB2LOGOFF              0x0002 /* trivial request/resp */
304         seq_printf(m, "\nLogoffs: %d sent %d failed",
305                    atomic_read(&sent[SMB2_LOGOFF_HE]),
306                    atomic_read(&failed[SMB2_LOGOFF_HE]));
307         seq_printf(m, "\nTreeConnects: %d sent %d failed",
308                    atomic_read(&sent[SMB2_TREE_CONNECT_HE]),
309                    atomic_read(&failed[SMB2_TREE_CONNECT_HE]));
310         seq_printf(m, "\nTreeDisconnects: %d sent %d failed",
311                    atomic_read(&sent[SMB2_TREE_DISCONNECT_HE]),
312                    atomic_read(&failed[SMB2_TREE_DISCONNECT_HE]));
313         seq_printf(m, "\nCreates: %d sent %d failed",
314                    atomic_read(&sent[SMB2_CREATE_HE]),
315                    atomic_read(&failed[SMB2_CREATE_HE]));
316         seq_printf(m, "\nCloses: %d sent %d failed",
317                    atomic_read(&sent[SMB2_CLOSE_HE]),
318                    atomic_read(&failed[SMB2_CLOSE_HE]));
319         seq_printf(m, "\nFlushes: %d sent %d failed",
320                    atomic_read(&sent[SMB2_FLUSH_HE]),
321                    atomic_read(&failed[SMB2_FLUSH_HE]));
322         seq_printf(m, "\nReads: %d sent %d failed",
323                    atomic_read(&sent[SMB2_READ_HE]),
324                    atomic_read(&failed[SMB2_READ_HE]));
325         seq_printf(m, "\nWrites: %d sent %d failed",
326                    atomic_read(&sent[SMB2_WRITE_HE]),
327                    atomic_read(&failed[SMB2_WRITE_HE]));
328         seq_printf(m, "\nLocks: %d sent %d failed",
329                    atomic_read(&sent[SMB2_LOCK_HE]),
330                    atomic_read(&failed[SMB2_LOCK_HE]));
331         seq_printf(m, "\nIOCTLs: %d sent %d failed",
332                    atomic_read(&sent[SMB2_IOCTL_HE]),
333                    atomic_read(&failed[SMB2_IOCTL_HE]));
334         seq_printf(m, "\nCancels: %d sent %d failed",
335                    atomic_read(&sent[SMB2_CANCEL_HE]),
336                    atomic_read(&failed[SMB2_CANCEL_HE]));
337         seq_printf(m, "\nEchos: %d sent %d failed",
338                    atomic_read(&sent[SMB2_ECHO_HE]),
339                    atomic_read(&failed[SMB2_ECHO_HE]));
340         seq_printf(m, "\nQueryDirectories: %d sent %d failed",
341                    atomic_read(&sent[SMB2_QUERY_DIRECTORY_HE]),
342                    atomic_read(&failed[SMB2_QUERY_DIRECTORY_HE]));
343         seq_printf(m, "\nChangeNotifies: %d sent %d failed",
344                    atomic_read(&sent[SMB2_CHANGE_NOTIFY_HE]),
345                    atomic_read(&failed[SMB2_CHANGE_NOTIFY_HE]));
346         seq_printf(m, "\nQueryInfos: %d sent %d failed",
347                    atomic_read(&sent[SMB2_QUERY_INFO_HE]),
348                    atomic_read(&failed[SMB2_QUERY_INFO_HE]));
349         seq_printf(m, "\nSetInfos: %d sent %d failed",
350                    atomic_read(&sent[SMB2_SET_INFO_HE]),
351                    atomic_read(&failed[SMB2_SET_INFO_HE]));
352         seq_printf(m, "\nOplockBreaks: %d sent %d failed",
353                    atomic_read(&sent[SMB2_OPLOCK_BREAK_HE]),
354                    atomic_read(&failed[SMB2_OPLOCK_BREAK_HE]));
355 #endif
356 }
357
358 static void
359 smb2_set_fid(struct cifsFileInfo *cfile, struct cifs_fid *fid, __u32 oplock)
360 {
361         /* struct cifsInodeInfo *cinode = CIFS_I(cfile->dentry->d_inode); */
362         cfile->fid.persistent_fid = fid->persistent_fid;
363         cfile->fid.volatile_fid = fid->volatile_fid;
364         /* cifs_set_oplock_level(cinode, oplock); */
365         /* cinode->can_cache_brlcks = cinode->clientCanCacheAll; */
366 }
367
368 static int
369 smb2_close_file(const unsigned int xid, struct cifs_tcon *tcon,
370                 struct cifs_fid *fid)
371 {
372         return SMB2_close(xid, tcon, fid->persistent_fid, fid->volatile_fid);
373 }
374
375 static int
376 smb2_flush_file(const unsigned int xid, struct cifs_tcon *tcon,
377                 struct cifs_fid *fid)
378 {
379         return SMB2_flush(xid, tcon, fid->persistent_fid, fid->volatile_fid);
380 }
381
382 static unsigned int
383 smb2_read_data_offset(char *buf)
384 {
385         struct smb2_read_rsp *rsp = (struct smb2_read_rsp *)buf;
386         return rsp->DataOffset;
387 }
388
389 static unsigned int
390 smb2_read_data_length(char *buf)
391 {
392         struct smb2_read_rsp *rsp = (struct smb2_read_rsp *)buf;
393         return le32_to_cpu(rsp->DataLength);
394 }
395
396
397 static int
398 smb2_sync_read(const unsigned int xid, struct cifsFileInfo *cfile,
399                struct cifs_io_parms *parms, unsigned int *bytes_read,
400                char **buf, int *buf_type)
401 {
402         parms->persistent_fid = cfile->fid.persistent_fid;
403         parms->volatile_fid = cfile->fid.volatile_fid;
404         return SMB2_read(xid, parms, bytes_read, buf, buf_type);
405 }
406
407 static int
408 smb2_sync_write(const unsigned int xid, struct cifsFileInfo *cfile,
409                 struct cifs_io_parms *parms, unsigned int *written,
410                 struct kvec *iov, unsigned long nr_segs)
411 {
412
413         parms->persistent_fid = cfile->fid.persistent_fid;
414         parms->volatile_fid = cfile->fid.volatile_fid;
415         return SMB2_write(xid, parms, written, iov, nr_segs);
416 }
417
418 struct smb_version_operations smb21_operations = {
419         .setup_request = smb2_setup_request,
420         .setup_async_request = smb2_setup_async_request,
421         .check_receive = smb2_check_receive,
422         .add_credits = smb2_add_credits,
423         .set_credits = smb2_set_credits,
424         .get_credits_field = smb2_get_credits_field,
425         .get_credits = smb2_get_credits,
426         .get_next_mid = smb2_get_next_mid,
427         .read_data_offset = smb2_read_data_offset,
428         .read_data_length = smb2_read_data_length,
429         .map_error = map_smb2_to_linux_error,
430         .find_mid = smb2_find_mid,
431         .check_message = smb2_check_message,
432         .dump_detail = smb2_dump_detail,
433         .clear_stats = smb2_clear_stats,
434         .print_stats = smb2_print_stats,
435         .need_neg = smb2_need_neg,
436         .negotiate = smb2_negotiate,
437         .negotiate_wsize = smb2_negotiate_wsize,
438         .negotiate_rsize = smb2_negotiate_rsize,
439         .sess_setup = SMB2_sess_setup,
440         .logoff = SMB2_logoff,
441         .tree_connect = SMB2_tcon,
442         .tree_disconnect = SMB2_tdis,
443         .is_path_accessible = smb2_is_path_accessible,
444         .can_echo = smb2_can_echo,
445         .echo = SMB2_echo,
446         .query_path_info = smb2_query_path_info,
447         .get_srv_inum = smb2_get_srv_inum,
448         .query_file_info = smb2_query_file_info,
449         .build_path_to_root = smb2_build_path_to_root,
450         .mkdir = smb2_mkdir,
451         .mkdir_setinfo = smb2_mkdir_setinfo,
452         .rmdir = smb2_rmdir,
453         .unlink = smb2_unlink,
454         .open = smb2_open_file,
455         .set_fid = smb2_set_fid,
456         .close = smb2_close_file,
457         .flush = smb2_flush_file,
458         .async_readv = smb2_async_readv,
459         .async_writev = smb2_async_writev,
460         .sync_read = smb2_sync_read,
461         .sync_write = smb2_sync_write,
462 };
463
464 struct smb_version_values smb21_values = {
465         .version_string = SMB21_VERSION_STRING,
466         .header_size = sizeof(struct smb2_hdr),
467         .max_header_size = MAX_SMB2_HDR_SIZE,
468         .read_rsp_size = sizeof(struct smb2_read_rsp) - 1,
469         .lock_cmd = SMB2_LOCK,
470         .cap_unix = 0,
471         .cap_nt_find = SMB2_NT_FIND,
472         .cap_large_files = SMB2_LARGE_FILES,
473 };