summaryrefslogtreecommitdiff
path: root/source3/modules/onefs_cbrl.c
blob: 33f35a7f34d87eceb166eadb049b5ee4d22e5690 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
/*
 * Unix SMB/CIFS implementation.
 * Support for OneFS system interfaces.
 *
 * Copyright (C) Zack Kirsch, 2009
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, see <http://www.gnu.org/licenses/>.
 */

#include "includes.h"
#include "onefs.h"

#include <ifs/ifs_syscalls.h>
#include <sys/isi_cifs_brl.h>
#include <isi_ecs/isi_ecs_cbrl.h>

#undef DBGC_CLASS
#define DBGC_CLASS DBGC_LOCKING

static uint64_t onefs_get_new_id(void) {
	static uint64_t id = 0;

	id++;

	return id;
}

enum onefs_cbrl_lock_state {ONEFS_CBRL_NONE, ONEFS_CBRL_ASYNC, ONEFS_CBRL_DONE,
	ONEFS_CBRL_ERROR};

struct onefs_cbrl_blr_state {
	uint64_t id;
	enum onefs_cbrl_lock_state state;
};

static char *onefs_cbrl_blr_state_str(const struct blocking_lock_record *blr)
{
	static fstring result;
	struct onefs_cbrl_blr_state *bs;

	SMB_ASSERT(blr);

	bs = (struct onefs_cbrl_blr_state *)blr->blr_private;

	if (bs == NULL) {
		fstrcpy(result, "NULL CBRL BLR state - Posix lock?");
		return result;
	}

	switch (bs->state) {
	case ONEFS_CBRL_NONE:
		fstr_sprintf(result, "CBRL BLR id=%llu: state=NONE", bs->id);
		break;
	case ONEFS_CBRL_ASYNC:
		fstr_sprintf(result, "CBRL BLR id=%llu: state=ASYNC", bs->id);
		break;
	case ONEFS_CBRL_DONE:
		fstr_sprintf(result, "CBRL BLR id=%llu: state=DONE", bs->id);
		break;
	case ONEFS_CBRL_ERROR:
		fstr_sprintf(result, "CBRL BLR id=%llu: state=ERROR", bs->id);
		break;
	default:
		fstr_sprintf(result, "CBRL BLR id=%llu: unknown state %d",
		    bs->id, bs->state);
		break;
	}

	return result;
}

static void onefs_cbrl_enumerate_blq(const char *fn)
{
	struct smbd_server_connection *sconn = smbd_server_conn;
	struct blocking_lock_record *blr;

	if (DEBUGLVL(10))
		return;

	DEBUG(10, ("CBRL BLR records (%s):\n", fn));

	if (sconn->using_smb2) {
		struct smbd_smb2_request *smb2req;
		for (smb2req = sconn->smb2.requests; smb2req; smb2req = nextreq) {
			blr = get_pending_smb2req_blr(smb2req);
			if (blr) {
				DEBUGADD(10, ("%s\n", onefs_cbrl_blr_state_str(blr)));
			}
		}
	} else {
		for (blr = sconn->smb1.locks.blocking_lock_queue; blr; blr = blr->next)
			DEBUGADD(10, ("%s\n", onefs_cbrl_blr_state_str(blr)));
	}
}

static struct blocking_lock_record *onefs_cbrl_find_blr(uint64_t id)
{
	struct smbd_server_connection *sconn = smbd_server_conn;
	struct blocking_lock_record *blr;
	struct onefs_cbrl_blr_state *bs;

	onefs_cbrl_enumerate_blq("onefs_cbrl_find_blr");

	if (sconn->using_smb2) {
		struct smbd_smb2_request *smb2req;
		for (smb2req = sconn->smb2.requests; smb2req; smb2req = nextreq) {
			blr = get_pending_smb2req_blr(smb2req);
			if (!blr) {
				continue;
			}
			bs = (struct onefs_cbrl_blr_state *)blr->blr_private;
			if (bs == NULL)	{
				continue;
			}
			if (bs->id == id) {
				DEBUG(10, ("found %s\n",
				    onefs_cbrl_blr_state_str(blr)));
				break;
			}
	} else {
		for (blr = sconn->smb1.locks.blocking_lock_queue; blr; blr = blr->next) {
			bs = (struct onefs_cbrl_blr_state *)blr->blr_private;

			/* We don't control all of the BLRs on the BLQ. */
			if (bs == NULL)
				continue;

			if (bs->id == id) {
				DEBUG(10, ("found %s\n",
				    onefs_cbrl_blr_state_str(blr)));
				break;
			}
		}
	}

	if (blr == NULL) {
		DEBUG(5, ("Could not find CBRL BLR for id %llu\n", id));
		return NULL;
	}

	return blr;
}

static void onefs_cbrl_async_success(uint64_t id)
{
	struct blocking_lock_record *blr;
	struct onefs_cbrl_blr_state *bs;
	uint16 num_locks;

	DEBUG(10, ("CBRL async success!\n"));

	/* Find BLR with id. Its okay not to find one (race with cancel) */
	blr = onefs_cbrl_find_blr(id);
	if (blr == NULL)
		return;

	bs = (struct onefs_cbrl_blr_state *)blr->blr_private;
	SMB_ASSERT(bs);
	SMB_ASSERT(bs->state == ONEFS_CBRL_ASYNC);

	blr->lock_num++;

	num_locks = SVAL(blr->req->vwv+7, 0);

	if (blr->lock_num == num_locks)
		bs->state = ONEFS_CBRL_DONE;
	else
		bs->state = ONEFS_CBRL_NONE;

	/* Self contend our own level 2 oplock. The kernel handles
	 * contention of other opener's level 2 oplocks. */
	contend_level2_oplocks_begin(blr->fsp,
	    LEVEL2_CONTEND_WINDOWS_BRL);

	/* Process the queue, to try the next lock or finish up. */
	process_blocking_lock_queue(smbd_server_conn);
}

static void onefs_cbrl_async_failure(uint64_t id)
{
	struct blocking_lock_record *blr;
	struct onefs_cbrl_blr_state *bs;

	DEBUG(10, ("CBRL async failure!\n"));

	/* Find BLR with id. Its okay not to find one (race with cancel) */
	blr = onefs_cbrl_find_blr(id);
	if (blr == NULL)
		return;

	bs = (struct onefs_cbrl_blr_state *)blr->blr_private;
	SMB_ASSERT(bs);

	SMB_ASSERT(bs->state == ONEFS_CBRL_ASYNC);
	bs->state = ONEFS_CBRL_ERROR;

	/* Process the queue. It will end up trying to retake the same lock,
	 * see the error in onefs_cbrl_lock_windows() and fail. */
	process_blocking_lock_queue(smbd_server_conn);
}

static struct cbrl_event_ops cbrl_ops =
    {.cbrl_async_success = onefs_cbrl_async_success,
     .cbrl_async_failure = onefs_cbrl_async_failure};
 
static void onefs_cbrl_events_handler(struct event_context *ev,
					struct fd_event *fde,
					uint16_t flags,
					void *private_data)
{
	DEBUG(10, ("onefs_cbrl_events_handler\n"));

	if (cbrl_event_dispatcher(&cbrl_ops)) {
		DEBUG(0, ("cbrl_event_dispatcher failed: %s\n",
			strerror(errno)));
	}
}

static void onefs_init_cbrl(void)
{
	static bool init_done = false;
	static int cbrl_event_fd;
	static struct fd_event *cbrl_fde;

	if (init_done)
		return;

	DEBUG(10, ("onefs_init_cbrl\n"));

	/* Register the event channel for CBRL. */
	cbrl_event_fd = cbrl_event_register();
	if (cbrl_event_fd == -1) {
		DEBUG(0, ("cbrl_event_register failed: %s\n",
			strerror(errno)));
		return;
	}

	DEBUG(10, ("cbrl_event_fd = %d\n", cbrl_event_fd));

	/* Register the CBRL event_fd with samba's event system */
	cbrl_fde = event_add_fd(smbd_event_context(),
				     NULL,
				     cbrl_event_fd,
				     EVENT_FD_READ,
				     onefs_cbrl_events_handler,
				     NULL);

	init_done = true;
	return;
}

/**
 * Blocking PID. As far as I can tell, the blocking_pid is only used to tell
 * whether a posix lock or a CIFS lock blocked us. If it was a posix lock,
 * Samba polls every 10 seconds, which we don't want. -zkirsch
 */
#define ONEFS_BLOCKING_PID 0xABCDABCD

/**
 * @param[in]     br_lck        Contains the fsp.
 * @param[in]     plock         Lock request.
 * @param[in]     blocking_lock Only used for figuring out the error.
 * @param[in,out] blr           The BLR for the already-deferred operation.
 */
NTSTATUS onefs_brl_lock_windows(vfs_handle_struct *handle,
				struct byte_range_lock *br_lck,
				struct lock_struct *plock,
				bool blocking_lock,
				struct blocking_lock_record *blr)
{
	int fd = br_lck->fsp->fh->fd;
	uint64_t id = 0;
	enum cbrl_lock_type type;
	bool async = false;
	bool pending = false;
	bool pending_async = false;
	int error;
	struct onefs_cbrl_blr_state *bs;
	NTSTATUS status;

	START_PROFILE(syscall_brl_lock);

	SMB_ASSERT(plock->lock_flav == WINDOWS_LOCK);
	SMB_ASSERT(plock->lock_type != UNLOCK_LOCK);

	onefs_cbrl_enumerate_blq("onefs_brl_lock_windows");

	/* Will only initialize the first time its called. */
	onefs_init_cbrl();

	switch (plock->lock_type) {
		case WRITE_LOCK:
			type = CBRL_LK_EX;
			break;
		case READ_LOCK:
			type = CBRL_LK_SH;
			break;
		case PENDING_WRITE_LOCK:
			/* Called when a blocking lock request is added - do an
			 * async lock. */
			type = CBRL_LK_EX;
			pending = true;
			async = true;
			break;
		case PENDING_READ_LOCK:
			/* Called when a blocking lock request is added - do an
			 * async lock. */
			type = CBRL_LK_SH;
			pending = true;
			async = true;
			break;
		default:
			/* UNLOCK_LOCK: should only be used for a POSIX_LOCK */
			smb_panic("Invalid plock->lock_type passed in to "
			    "onefs_brl_lock_windows");
	}

	/* Figure out if we're actually doing the lock or a no-op. We need to
	 * do a no-op when process_blocking_lock_queue calls back into us.
	 *
	 * We know process_* is calling into us if a blr is passed in and
	 * pending is false. */
	if (!pending && blr) {
		/* Check the BLR state. */
		bs = (struct onefs_cbrl_blr_state *)blr->blr_private;
		SMB_ASSERT(bs);

		/* ASYNC still in progress: The process_* calls will keep
		 * calling even if we haven't gotten the lock. Keep erroring
		 * without calling ifs_cbrl, or getting/setting an id. */
		if (bs->state == ONEFS_CBRL_ASYNC) {
			goto failure;
		}
		else if (bs->state == ONEFS_CBRL_ERROR) {
			END_PROFILE(syscall_brl_lock);
			return NT_STATUS_NO_MEMORY;
		}

		SMB_ASSERT(bs->state == ONEFS_CBRL_NONE);
		async = true;
	}

	if (async) {
		SMB_ASSERT(blocking_lock);
		SMB_ASSERT(blr);
		id = onefs_get_new_id();
	}

	DEBUG(10, ("Calling ifs_cbrl(LOCK)...\n"));
	error = ifs_cbrl(fd, CBRL_OP_LOCK, type, plock->start,
	    plock->size, async, id, plock->context.smbpid, plock->context.tid,
	    plock->fnum);
	if (!error) {
		goto success;
	} else if (errno == EWOULDBLOCK) {
		SMB_ASSERT(!async);
	} else if (errno == EINPROGRESS) {
		SMB_ASSERT(async);

		if (pending) {
			/* Talloc a new BLR private state. */
			blr->blr_private = talloc(blr, struct onefs_cbrl_blr_state);
			pending_async = true;
		}

		/* Store the new id in the BLR private state. */
		bs = (struct onefs_cbrl_blr_state *)blr->blr_private;
		bs->id = id;
		bs->state = ONEFS_CBRL_ASYNC;
	} else {
		DEBUG(0, ("onefs_brl_lock_windows failure: error=%d (%s).\n",
			errno, strerror(errno)));
	}

failure:

	END_PROFILE(syscall_brl_lock);

	/* Failure - error or async. */
	plock->context.smbpid = (uint32) ONEFS_BLOCKING_PID;

	if (pending_async)
		status = NT_STATUS_OK;
	else
		status = brl_lock_failed(br_lck->fsp, plock, blocking_lock);

	DEBUG(10, ("returning %s.\n", nt_errstr(status)));
	return status;

success:
	/* Self contend our own level 2 oplock. The kernel handles
	 * contention of other opener's level 2 oplocks. */
	contend_level2_oplocks_begin(br_lck->fsp,
	    LEVEL2_CONTEND_WINDOWS_BRL);

	END_PROFILE(syscall_brl_lock);

	/* Success. */
	onefs_cbrl_enumerate_blq("onefs_brl_unlock_windows");
	DEBUG(10, ("returning NT_STATUS_OK.\n"));
	return NT_STATUS_OK;
}

bool onefs_brl_unlock_windows(vfs_handle_struct *handle,
			      struct messaging_context *msg_ctx,
			      struct byte_range_lock *br_lck,
			      const struct lock_struct *plock)
{
	int error;
	int fd = br_lck->fsp->fh->fd;

	START_PROFILE(syscall_brl_unlock);

	SMB_ASSERT(plock->lock_flav == WINDOWS_LOCK);
	SMB_ASSERT(plock->lock_type == UNLOCK_LOCK);

	DEBUG(10, ("Calling ifs_cbrl(UNLOCK)...\n"));
	error = ifs_cbrl(fd, CBRL_OP_UNLOCK, CBRL_LK_SH,
	    plock->start, plock->size, false, 0, plock->context.smbpid,
	    plock->context.tid, plock->fnum);

	END_PROFILE(syscall_brl_unlock);

	if (error) {
		DEBUG(10, ("returning false.\n"));
		return false;
	}

	/* For symmetry purposes, end our oplock contention even though its
	 * currently a no-op. */
	contend_level2_oplocks_end(br_lck->fsp, LEVEL2_CONTEND_WINDOWS_BRL);

	DEBUG(10, ("returning true.\n"));
	return true;

	/* Problem with storing things in TDB: I won't know what BRL to unlock in the TDB.
	 *  - I could fake it?
	 *  - I could send Samba a message with which lock is being unlocked?
	 *  - I could *easily* make the "id" something you always pass in to
	 *  lock, unlock or cancel -- it identifies a lock. Makes sense!
	 */
}

/* Default implementation only calls this on PENDING locks. */
bool onefs_brl_cancel_windows(vfs_handle_struct *handle,
			      struct byte_range_lock *br_lck,
			      struct lock_struct *plock,
			      struct blocking_lock_record *blr)
{
	int error;
	int fd = br_lck->fsp->fh->fd;
	struct onefs_cbrl_blr_state *bs;

	START_PROFILE(syscall_brl_cancel);

	SMB_ASSERT(plock);
	SMB_ASSERT(plock->lock_flav == WINDOWS_LOCK);
	SMB_ASSERT(blr);

	onefs_cbrl_enumerate_blq("onefs_brl_cancel_windows");

	bs = ((struct onefs_cbrl_blr_state *)blr->blr_private);
	SMB_ASSERT(bs);

	if (bs->state == ONEFS_CBRL_DONE || bs->state == ONEFS_CBRL_ERROR) {
		/* No-op. */
		DEBUG(10, ("State=%d, returning true\n", bs->state));
		END_PROFILE(syscall_brl_cancel);
		return true;
	}

	SMB_ASSERT(bs->state == ONEFS_CBRL_NONE ||
	    bs->state == ONEFS_CBRL_ASYNC);

	/* A real cancel. */
	DEBUG(10, ("Calling ifs_cbrl(CANCEL)...\n"));
	error = ifs_cbrl(fd, CBRL_OP_CANCEL, CBRL_LK_UNSPEC, plock->start,
	    plock->size, false, bs->id, plock->context.smbpid,
	    plock->context.tid, plock->fnum);

	END_PROFILE(syscall_brl_cancel);

	if (error) {
		DEBUG(10, ("returning false\n"));
		bs->state = ONEFS_CBRL_ERROR;
		return false;
	}

	bs->state = ONEFS_CBRL_DONE;
	onefs_cbrl_enumerate_blq("onefs_brl_cancel_windows");
	DEBUG(10, ("returning true\n"));
	return true;
}

bool onefs_strict_lock(vfs_handle_struct *handle,
			files_struct *fsp,
			struct lock_struct *plock)
{
	int error;

	START_PROFILE(syscall_strict_lock);

	SMB_ASSERT(plock->lock_type == READ_LOCK ||
	    plock->lock_type == WRITE_LOCK);

        if (!lp_locking(handle->conn->params) ||
	    !lp_strict_locking(handle->conn->params)) {
		END_PROFILE(syscall_strict_lock);
                return True;
        }

	if (plock->lock_flav == POSIX_LOCK) {
		END_PROFILE(syscall_strict_lock);
		return SMB_VFS_NEXT_STRICT_LOCK(handle, fsp, plock);
	}

	if (plock->size == 0) {
		END_PROFILE(syscall_strict_lock);
                return True;
	}

	error = ifs_cbrl(fsp->fh->fd, CBRL_OP_LOCK,
	    plock->lock_type == READ_LOCK ? CBRL_LK_RD : CBRL_LK_WR,
	    plock->start, plock->size, 0, 0, plock->context.smbpid,
	    plock->context.tid, plock->fnum);

	END_PROFILE(syscall_strict_lock);

	return (error == 0);
}

void onefs_strict_unlock(vfs_handle_struct *handle,
			files_struct *fsp,
			struct lock_struct *plock)
{
	START_PROFILE(syscall_strict_unlock);

	SMB_ASSERT(plock->lock_type == READ_LOCK ||
	    plock->lock_type == WRITE_LOCK);

        if (!lp_locking(handle->conn->params) ||
	    !lp_strict_locking(handle->conn->params)) {
		END_PROFILE(syscall_strict_unlock);
		return;
        }

	if (plock->lock_flav == POSIX_LOCK) {
		SMB_VFS_NEXT_STRICT_UNLOCK(handle, fsp, plock);
		END_PROFILE(syscall_strict_unlock);
		return;
	}

	if (plock->size == 0) {
		END_PROFILE(syscall_strict_unlock);
		return;
	}

	if (fsp->fh) {
		ifs_cbrl(fsp->fh->fd, CBRL_OP_UNLOCK,
		    plock->lock_type == READ_LOCK ? CBRL_LK_RD : CBRL_LK_WR,
		    plock->start, plock->size, 0, 0, plock->context.smbpid,
		    plock->context.tid, plock->fnum);
	}

	END_PROFILE(syscall_strict_unlock);
}

/* TODO Optimization: Abstract out brl_get_locks() in the Windows case.
 * We'll malloc some memory or whatever (can't return NULL), but not actually
 * touch the TDB. */

/* XXX brl_locktest: CBRL does not support calling this, but its only for
 * strict locking. Add empty VOP? */

/* XXX brl_lockquery: CBRL does not support calling this for WINDOWS LOCKS, but
 * its only called for POSIX LOCKS. Add empty VOP? */

/* XXX brl_close_fnum: CBRL will do this automatically. I think this is a NO-OP
 * for us, we could add an empty VOP. */