xref: /spdk/module/bdev/daos/bdev_daos.c (revision 510f4c134a21b45ff3a5add9ebc6c6cf7e49aeab)
1 /*   SPDX-License-Identifier: BSD-3-Clause
2  *   Copyright (c) Intel Corporation.
3  *   All rights reserved.
4  *   Copyright (c) croit GmbH.
5  *   All rights reserved.
6  */
7 
8 #include <sys/queue.h>
9 
10 #include "spdk/bdev.h"
11 #include "spdk/bdev_module.h"
12 #include "spdk/endian.h"
13 #include "spdk/env.h"
14 #include "spdk/json.h"
15 #include "spdk/thread.h"
16 #include "spdk/queue.h"
17 #include "spdk/string.h"
18 #include "spdk/stdinc.h"
19 #include "spdk/log.h"
20 
21 #include <daos.h>
22 #include <daos_event.h>
23 #include <daos_fs.h>
24 #include <daos_types.h>
25 #include <daos_pool.h>
26 #include <daos_cont.h>
27 #include <daos_errno.h>
28 
29 #include "bdev_daos.h"
30 
31 #define BDEV_DAOS_IOVECS_MAX 32
32 
33 struct bdev_daos_task {
34 	daos_event_t ev;
35 	struct spdk_thread *submit_td;
36 	struct spdk_bdev_io *bdev_io;
37 
38 	enum spdk_bdev_io_status status;
39 
40 	uint64_t offset;
41 
42 	/* DAOS version of iovec and scatter/gather */
43 	daos_size_t read_size;
44 	d_iov_t diovs[BDEV_DAOS_IOVECS_MAX];
45 	d_sg_list_t sgl;
46 };
47 
48 struct bdev_daos {
49 	struct spdk_bdev disk;
50 
51 	char pool_name[DAOS_PROP_MAX_LABEL_BUF_LEN];
52 	char cont_name[DAOS_PROP_MAX_LABEL_BUF_LEN];
53 
54 	struct bdev_daos_task *reset_task;
55 	struct spdk_poller    *reset_retry_timer;
56 };
57 
58 struct bdev_daos_io_channel {
59 	struct bdev_daos *disk;
60 	struct spdk_poller *poller;
61 
62 	daos_handle_t pool;
63 	daos_handle_t cont;
64 
65 	dfs_t *dfs;
66 	dfs_obj_t *obj;
67 	daos_handle_t queue;
68 };
69 
70 static uint32_t g_bdev_daos_init_count = 0;
71 static pthread_mutex_t g_bdev_daos_init_mutex = PTHREAD_MUTEX_INITIALIZER;
72 
73 static int bdev_daos_initialize(void);
74 
75 static int bdev_get_daos_engine(void);
76 static int bdev_daos_put_engine(void);
77 
78 static int
79 bdev_daos_get_ctx_size(void)
80 {
81 	return sizeof(struct bdev_daos_task);
82 }
83 
84 static struct spdk_bdev_module daos_if = {
85 	.name = "daos",
86 	.module_init = bdev_daos_initialize,
87 	.get_ctx_size = bdev_daos_get_ctx_size,
88 };
89 
90 SPDK_BDEV_MODULE_REGISTER(daos, &daos_if)
91 
92 static void
93 bdev_daos_free(struct bdev_daos *bdev_daos)
94 {
95 	if (!bdev_daos) {
96 		return;
97 	}
98 
99 	free(bdev_daos->disk.name);
100 	free(bdev_daos);
101 }
102 
103 static void
104 bdev_daos_destruct_cb(void *io_device)
105 {
106 	int rc;
107 	struct bdev_daos *daos = io_device;
108 
109 	assert(daos != NULL);
110 
111 	bdev_daos_free(daos);
112 
113 	rc = bdev_daos_put_engine();
114 	if (rc) {
115 		SPDK_ERRLOG("could not de-initialize DAOS engine: " DF_RC "\n", DP_RC(rc));
116 	}
117 }
118 
119 static int
120 bdev_daos_destruct(void *ctx)
121 {
122 	struct bdev_daos *daos = ctx;
123 
124 	SPDK_NOTICELOG("%s: destroying bdev_daos device\n", daos->disk.name);
125 
126 	spdk_io_device_unregister(daos, bdev_daos_destruct_cb);
127 
128 	return 0;
129 }
130 
131 static void
132 _bdev_daos_io_complete(void *bdev_daos_task)
133 {
134 	struct bdev_daos_task *task = bdev_daos_task;
135 
136 	SPDK_DEBUGLOG(bdev_daos, "completed IO at %#lx with status %s\n", task->offset,
137 		      task->status == SPDK_BDEV_IO_STATUS_SUCCESS ? "SUCCESS" : "FAILURE");
138 
139 	spdk_bdev_io_complete(spdk_bdev_io_from_ctx(task), task->status);
140 }
141 
142 static void
143 bdev_daos_io_complete(struct spdk_bdev_io *bdev_io, enum spdk_bdev_io_status status)
144 {
145 	struct bdev_daos_task *task = (struct bdev_daos_task *)bdev_io->driver_ctx;
146 	struct spdk_thread *current_thread = spdk_get_thread();
147 
148 	assert(task->submit_td != NULL);
149 
150 	task->status = status;
151 	if (task->submit_td != current_thread) {
152 		spdk_thread_send_msg(task->submit_td, _bdev_daos_io_complete, task);
153 	} else {
154 		_bdev_daos_io_complete(task);
155 	}
156 }
157 
158 static int64_t
159 bdev_daos_writev(struct bdev_daos *daos, struct bdev_daos_io_channel *ch,
160 		 struct bdev_daos_task *task,
161 		 struct iovec *iov, int iovcnt, uint64_t nbytes, uint64_t offset)
162 {
163 	int rc;
164 	struct iovec *io = iov;
165 
166 	SPDK_DEBUGLOG(bdev_daos, "write %d iovs size %lu to off: %#lx\n",
167 		      iovcnt, nbytes, offset);
168 
169 	assert(ch != NULL);
170 	assert(daos != NULL);
171 	assert(task != NULL);
172 	assert(iov != NULL);
173 
174 	if (iovcnt > BDEV_DAOS_IOVECS_MAX) {
175 		SPDK_ERRLOG("iovs number [%d] exceeds max allowed limit [%d]\n", iovcnt,
176 			    BDEV_DAOS_IOVECS_MAX);
177 		return -E2BIG;
178 	}
179 
180 	if ((rc = daos_event_init(&task->ev, ch->queue, NULL))) {
181 		SPDK_ERRLOG("%s: could not initialize async event: " DF_RC "\n",
182 			    daos->disk.name, DP_RC(rc));
183 		return -EINVAL;
184 	}
185 
186 	for (int i = 0; i < iovcnt; i++, iov++) {
187 		d_iov_set(&(task->diovs[i]), io->iov_base, io->iov_len);
188 	}
189 
190 	task->sgl.sg_nr = iovcnt;
191 	task->sgl.sg_nr_out = 0;
192 	task->sgl.sg_iovs = task->diovs;
193 	task->offset = offset;
194 
195 	if ((rc = dfs_write(ch->dfs, ch->obj, &task->sgl, offset, &task->ev))) {
196 		SPDK_ERRLOG("%s: could not start async write: " DF_RC "\n",
197 			    daos->disk.name, DP_RC(rc));
198 		daos_event_fini(&task->ev);
199 		return -EINVAL;
200 	}
201 
202 	return nbytes;
203 }
204 
205 static int64_t
206 bdev_daos_readv(struct bdev_daos *daos, struct bdev_daos_io_channel *ch,
207 		struct bdev_daos_task *task,
208 		struct iovec *iov, int iovcnt, uint64_t nbytes, uint64_t offset)
209 {
210 	int rc;
211 	struct iovec *io = iov;
212 
213 	SPDK_DEBUGLOG(bdev_daos, "read %d iovs size %lu to off: %#lx\n",
214 		      iovcnt, nbytes, offset);
215 
216 	assert(ch != NULL);
217 	assert(daos != NULL);
218 	assert(task != NULL);
219 	assert(iov != NULL);
220 
221 	if (iovcnt > BDEV_DAOS_IOVECS_MAX) {
222 		SPDK_ERRLOG("iovs number [%d] exceeds max allowed limit [%d]\n", iovcnt,
223 			    BDEV_DAOS_IOVECS_MAX);
224 		return -E2BIG;
225 	}
226 
227 	if ((rc = daos_event_init(&task->ev, ch->queue, NULL))) {
228 		SPDK_ERRLOG("%s: could not initialize async event: " DF_RC "\n",
229 			    daos->disk.name, DP_RC(rc));
230 		return -EINVAL;
231 	}
232 
233 	for (int i = 0; i < iovcnt; i++, io++) {
234 		d_iov_set(&(task->diovs[i]), io->iov_base, io->iov_len);
235 	}
236 
237 	task->sgl.sg_nr = iovcnt;
238 	task->sgl.sg_nr_out = 0;
239 	task->sgl.sg_iovs = task->diovs;
240 	task->offset = offset;
241 
242 	if ((rc = dfs_read(ch->dfs, ch->obj, &task->sgl, offset, &task->read_size, &task->ev))) {
243 		SPDK_ERRLOG("%s: could not start async read: " DF_RC "\n",
244 			    daos->disk.name, DP_RC(rc));
245 		daos_event_fini(&task->ev);
246 		return -EINVAL;
247 	}
248 
249 	return nbytes;
250 }
251 
252 static void
253 bdev_daos_get_buf_cb(struct spdk_io_channel *ch, struct spdk_bdev_io *bdev_io,
254 		     bool success)
255 {
256 	int64_t rc;
257 	struct bdev_daos_io_channel *dch = spdk_io_channel_get_ctx(ch);
258 
259 	if (!success) {
260 		bdev_daos_io_complete(bdev_io, SPDK_BDEV_IO_STATUS_FAILED);
261 		return;
262 	}
263 
264 	rc = bdev_daos_readv((struct bdev_daos *)bdev_io->bdev->ctxt,
265 			     dch,
266 			     (struct bdev_daos_task *)bdev_io->driver_ctx,
267 			     bdev_io->u.bdev.iovs,
268 			     bdev_io->u.bdev.iovcnt,
269 			     bdev_io->u.bdev.num_blocks * bdev_io->bdev->blocklen,
270 			     bdev_io->u.bdev.offset_blocks * bdev_io->bdev->blocklen);
271 
272 	if (rc < 0) {
273 		spdk_bdev_io_complete(bdev_io, SPDK_BDEV_IO_STATUS_FAILED);
274 		return;
275 	}
276 }
277 
278 static void
279 _bdev_daos_get_io_inflight(struct spdk_io_channel_iter *i)
280 {
281 	struct spdk_io_channel *ch = spdk_io_channel_iter_get_channel(i);
282 	struct bdev_daos_io_channel *dch = spdk_io_channel_get_ctx(ch);
283 	int io_inflight = daos_eq_query(dch->queue, DAOS_EQR_WAITING, 0, NULL);
284 
285 	if (io_inflight > 0) {
286 		spdk_for_each_channel_continue(i, -1);
287 		return;
288 	}
289 
290 	spdk_for_each_channel_continue(i, 0);
291 }
292 
293 static int bdev_daos_reset_retry_timer(void *arg);
294 
295 static void
296 _bdev_daos_get_io_inflight_done(struct spdk_io_channel_iter *i, int status)
297 {
298 	struct bdev_daos *daos = spdk_io_channel_iter_get_ctx(i);
299 
300 	if (status == -1) {
301 		daos->reset_retry_timer = SPDK_POLLER_REGISTER(bdev_daos_reset_retry_timer, daos, 1000);
302 		return;
303 	}
304 
305 	spdk_bdev_io_complete(spdk_bdev_io_from_ctx(daos->reset_task), SPDK_BDEV_IO_STATUS_SUCCESS);
306 }
307 
308 static int
309 bdev_daos_reset_retry_timer(void *arg)
310 {
311 	struct bdev_daos *daos = arg;
312 
313 	if (daos->reset_retry_timer) {
314 		spdk_poller_unregister(&daos->reset_retry_timer);
315 	}
316 
317 	spdk_for_each_channel(daos,
318 			      _bdev_daos_get_io_inflight,
319 			      daos,
320 			      _bdev_daos_get_io_inflight_done);
321 
322 	return SPDK_POLLER_BUSY;
323 }
324 
325 static void
326 bdev_daos_reset(struct bdev_daos *daos, struct bdev_daos_task *task)
327 {
328 	assert(daos != NULL);
329 	assert(task != NULL);
330 
331 	daos->reset_task = task;
332 	bdev_daos_reset_retry_timer(daos);
333 }
334 
335 
336 static int64_t
337 bdev_daos_unmap(struct bdev_daos_io_channel *ch, uint64_t nbytes,
338 		uint64_t offset)
339 {
340 	SPDK_DEBUGLOG(bdev_daos, "unmap at %#lx with size %#lx\n", offset, nbytes);
341 	return dfs_punch(ch->dfs, ch->obj, offset, nbytes);
342 }
343 
344 static void
345 _bdev_daos_submit_request(struct spdk_io_channel *ch, struct spdk_bdev_io *bdev_io)
346 {
347 	struct bdev_daos_io_channel *dch = spdk_io_channel_get_ctx(ch);
348 
349 	int64_t rc;
350 	switch (bdev_io->type) {
351 	case SPDK_BDEV_IO_TYPE_READ:
352 		spdk_bdev_io_get_buf(bdev_io, bdev_daos_get_buf_cb,
353 				     bdev_io->u.bdev.num_blocks * bdev_io->bdev->blocklen);
354 		break;
355 
356 	case SPDK_BDEV_IO_TYPE_WRITE:
357 		rc = bdev_daos_writev((struct bdev_daos *)bdev_io->bdev->ctxt,
358 				      dch,
359 				      (struct bdev_daos_task *)bdev_io->driver_ctx,
360 				      bdev_io->u.bdev.iovs,
361 				      bdev_io->u.bdev.iovcnt,
362 				      bdev_io->u.bdev.num_blocks * bdev_io->bdev->blocklen,
363 				      bdev_io->u.bdev.offset_blocks * bdev_io->bdev->blocklen);
364 		if (rc < 0) {
365 			spdk_bdev_io_complete(bdev_io, SPDK_BDEV_IO_STATUS_FAILED);
366 			return;
367 		}
368 		break;
369 
370 	case SPDK_BDEV_IO_TYPE_RESET:
371 		/* Can't cancel in-flight requests, but can wait for their completions */
372 		bdev_daos_reset((struct bdev_daos *)bdev_io->bdev->ctxt,
373 				(struct bdev_daos_task *)bdev_io->driver_ctx);
374 		break;
375 
376 	case SPDK_BDEV_IO_TYPE_FLUSH:
377 		/* NOOP because DAOS requests land on PMEM and writes are persistent upon completion */
378 		spdk_bdev_io_complete(bdev_io, SPDK_BDEV_IO_STATUS_SUCCESS);
379 		break;
380 
381 	case SPDK_BDEV_IO_TYPE_UNMAP:
382 		rc = bdev_daos_unmap(dch,
383 				     bdev_io->u.bdev.num_blocks * bdev_io->bdev->blocklen,
384 				     bdev_io->u.bdev.offset_blocks * bdev_io->bdev->blocklen);
385 		if (!rc) {
386 			spdk_bdev_io_complete(bdev_io, SPDK_BDEV_IO_STATUS_SUCCESS);
387 		} else {
388 			SPDK_DEBUGLOG(bdev_daos, "%s: could not unmap: " DF_RC "\n",
389 				      dch->disk->disk.name, DP_RC((int)rc));
390 			spdk_bdev_io_complete(bdev_io, SPDK_BDEV_IO_STATUS_FAILED);
391 		}
392 
393 		break;
394 
395 	default:
396 		SPDK_ERRLOG("Wrong io type\n");
397 		spdk_bdev_io_complete(bdev_io, SPDK_BDEV_IO_STATUS_FAILED);
398 		break;
399 	}
400 }
401 
402 static void
403 bdev_daos_submit_request(struct spdk_io_channel *ch, struct spdk_bdev_io *bdev_io)
404 {
405 	struct bdev_daos_task *task = (struct bdev_daos_task *)bdev_io->driver_ctx;
406 	struct spdk_thread *submit_td = spdk_io_channel_get_thread(ch);
407 
408 	assert(task != NULL);
409 
410 	task->submit_td = submit_td;
411 	task->bdev_io = bdev_io;
412 
413 	_bdev_daos_submit_request(ch, bdev_io);
414 }
415 
416 #define POLLING_EVENTS_NUM 64
417 
418 static int
419 bdev_daos_channel_poll(void *arg)
420 {
421 	daos_event_t *evp[POLLING_EVENTS_NUM];
422 	struct bdev_daos_io_channel *ch = arg;
423 
424 	assert(ch != NULL);
425 	assert(ch->disk != NULL);
426 
427 	int rc = daos_eq_poll(ch->queue, 0, DAOS_EQ_NOWAIT,
428 			      POLLING_EVENTS_NUM, evp);
429 
430 	if (rc < 0) {
431 		SPDK_DEBUGLOG(bdev_daos, "%s: could not poll daos event queue: " DF_RC "\n",
432 			      ch->disk->disk.name, DP_RC(rc));
433 		/*
434 		 * TODO: There are cases when this is self healing, e.g.
435 		 * brief network issues, DAOS agent restarting etc.
436 		 * However, if the issue persists over some time better would be
437 		 * to remove a bdev or the whole controller
438 		 */
439 		return SPDK_POLLER_BUSY;
440 	}
441 
442 	for (int i = 0; i < rc; ++i) {
443 		struct bdev_daos_task *task = container_of(evp[i], struct bdev_daos_task, ev);
444 		enum spdk_bdev_io_status status = SPDK_BDEV_IO_STATUS_SUCCESS;
445 
446 		assert(task != NULL);
447 
448 		if (task->ev.ev_error != DER_SUCCESS) {
449 			status = SPDK_BDEV_IO_STATUS_FAILED;
450 		}
451 
452 		daos_event_fini(&task->ev);
453 		bdev_daos_io_complete(task->bdev_io, status);
454 	}
455 
456 	return rc > 0 ? SPDK_POLLER_BUSY : SPDK_POLLER_IDLE;
457 }
458 
459 static bool
460 bdev_daos_io_type_supported(void *ctx, enum spdk_bdev_io_type io_type)
461 {
462 	switch (io_type) {
463 	case SPDK_BDEV_IO_TYPE_READ:
464 	case SPDK_BDEV_IO_TYPE_WRITE:
465 	case SPDK_BDEV_IO_TYPE_RESET:
466 	case SPDK_BDEV_IO_TYPE_FLUSH:
467 	case SPDK_BDEV_IO_TYPE_UNMAP:
468 		return true;
469 
470 	default:
471 		return false;
472 	}
473 }
474 
475 static struct spdk_io_channel *
476 bdev_daos_get_io_channel(void *ctx)
477 {
478 	return spdk_get_io_channel(ctx);
479 }
480 
481 static void
482 bdev_daos_write_json_config(struct spdk_bdev *bdev, struct spdk_json_write_ctx *w)
483 {
484 	char uuid_str[SPDK_UUID_STRING_LEN];
485 	struct bdev_daos *daos = bdev->ctxt;
486 
487 	spdk_json_write_object_begin(w);
488 
489 	spdk_json_write_named_string(w, "method", "bdev_daos_create");
490 
491 	spdk_json_write_named_object_begin(w, "params");
492 	spdk_json_write_named_string(w, "name", bdev->name);
493 	spdk_json_write_named_string(w, "pool", daos->pool_name);
494 	spdk_json_write_named_string(w, "cont", daos->cont_name);
495 	spdk_json_write_named_uint64(w, "num_blocks", bdev->blockcnt);
496 	spdk_json_write_named_uint32(w, "block_size", bdev->blocklen);
497 	spdk_uuid_fmt_lower(uuid_str, sizeof(uuid_str), &bdev->uuid);
498 	spdk_json_write_named_string(w, "uuid", uuid_str);
499 
500 	spdk_json_write_object_end(w);
501 
502 	spdk_json_write_object_end(w);
503 }
504 
505 static const struct spdk_bdev_fn_table daos_fn_table = {
506 	.destruct		= bdev_daos_destruct,
507 	.submit_request		= bdev_daos_submit_request,
508 	.io_type_supported	= bdev_daos_io_type_supported,
509 	.get_io_channel		= bdev_daos_get_io_channel,
510 	.write_config_json	= bdev_daos_write_json_config,
511 };
512 
513 static void *
514 _bdev_daos_io_channel_create_cb(void *ctx)
515 {
516 	int rc = 0 ;
517 	struct bdev_daos_io_channel *ch = ctx;
518 	struct bdev_daos *daos = ch->disk;
519 
520 	daos_pool_info_t pinfo;
521 	daos_cont_info_t cinfo;
522 	daos_oclass_id_t obj_class = OC_SX;
523 
524 	int fd_oflag = O_CREAT | O_RDWR;
525 	mode_t mode = S_IFREG | S_IRWXU | S_IRWXG | S_IRWXO;
526 
527 	rc = bdev_get_daos_engine();
528 	if (rc) {
529 		SPDK_ERRLOG("could not initialize DAOS engine: " DF_RC "\n", DP_RC(rc));
530 		return NULL;
531 	}
532 
533 	SPDK_DEBUGLOG(bdev_daos, "connecting to daos pool '%s'\n", daos->pool_name);
534 	if ((rc = daos_pool_connect(daos->pool_name, NULL, DAOS_PC_RW, &ch->pool, &pinfo, NULL))) {
535 		SPDK_ERRLOG("%s: could not connect to daos pool: " DF_RC "\n",
536 			    daos->disk.name, DP_RC(rc));
537 		return NULL;
538 	}
539 	SPDK_DEBUGLOG(bdev_daos, "connecting to daos container '%s'\n", daos->cont_name);
540 	if ((rc = daos_cont_open(ch->pool, daos->cont_name, DAOS_COO_RW, &ch->cont, &cinfo, NULL))) {
541 		SPDK_ERRLOG("%s: could not open daos container: " DF_RC "\n",
542 			    daos->disk.name, DP_RC(rc));
543 		goto cleanup_pool;
544 	}
545 	SPDK_DEBUGLOG(bdev_daos, "mounting daos dfs\n");
546 	if ((rc = dfs_mount(ch->pool, ch->cont, O_RDWR, &ch->dfs))) {
547 		SPDK_ERRLOG("%s: could not mount daos dfs: " DF_RC "\n",
548 			    daos->disk.name, DP_RC(rc));
549 		goto cleanup_cont;
550 	}
551 	SPDK_DEBUGLOG(bdev_daos, "opening dfs object\n");
552 	if ((rc = dfs_open(ch->dfs, NULL, daos->disk.name, mode, fd_oflag, obj_class,
553 			   0, NULL, &ch->obj))) {
554 		SPDK_ERRLOG("%s: could not open dfs object: " DF_RC "\n",
555 			    daos->disk.name, DP_RC(rc));
556 		goto cleanup_mount;
557 	}
558 	if ((rc = daos_eq_create(&ch->queue))) {
559 		SPDK_ERRLOG("%s: could not create daos event queue: " DF_RC "\n",
560 			    daos->disk.name, DP_RC(rc));
561 		goto cleanup_obj;
562 	}
563 
564 	return ctx;
565 
566 cleanup_obj:
567 	dfs_release(ch->obj);
568 cleanup_mount:
569 	dfs_umount(ch->dfs);
570 cleanup_cont:
571 	daos_cont_close(ch->cont, NULL);
572 cleanup_pool:
573 	daos_pool_disconnect(ch->pool, NULL);
574 
575 	return NULL;
576 }
577 
578 static int
579 bdev_daos_io_channel_create_cb(void *io_device, void *ctx_buf)
580 {
581 	struct bdev_daos_io_channel *ch = ctx_buf;
582 
583 	ch->disk = io_device;
584 
585 	if (spdk_call_unaffinitized(_bdev_daos_io_channel_create_cb, ch) == NULL) {
586 		return EINVAL;
587 	}
588 
589 	SPDK_DEBUGLOG(bdev_daos, "%s: starting daos event queue poller\n",
590 		      ch->disk->disk.name);
591 
592 	ch->poller = SPDK_POLLER_REGISTER(bdev_daos_channel_poll, ch, 0);
593 
594 	return 0;
595 }
596 
597 static void
598 bdev_daos_io_channel_destroy_cb(void *io_device, void *ctx_buf)
599 {
600 	int rc;
601 	struct bdev_daos_io_channel *ch = ctx_buf;
602 
603 	SPDK_DEBUGLOG(bdev_daos, "stopping daos event queue poller\n");
604 
605 	spdk_poller_unregister(&ch->poller);
606 
607 	if ((rc = daos_eq_destroy(ch->queue, DAOS_EQ_DESTROY_FORCE))) {
608 		SPDK_ERRLOG("could not destroy daos event queue: " DF_RC "\n", DP_RC(rc));
609 	}
610 	if ((rc = dfs_release(ch->obj))) {
611 		SPDK_ERRLOG("could not release dfs object: " DF_RC "\n", DP_RC(rc));
612 	}
613 	if ((rc = dfs_umount(ch->dfs))) {
614 		SPDK_ERRLOG("could not unmount dfs: " DF_RC "\n", DP_RC(rc));
615 	}
616 	if ((rc = daos_cont_close(ch->cont, NULL))) {
617 		SPDK_ERRLOG("could not close container: " DF_RC "\n", DP_RC(rc));
618 	}
619 	if ((rc = daos_pool_disconnect(ch->pool, NULL))) {
620 		SPDK_ERRLOG("could not disconnect from pool: " DF_RC "\n", DP_RC(rc));
621 	}
622 	rc = bdev_daos_put_engine();
623 	if (rc) {
624 		SPDK_ERRLOG("could not de-initialize DAOS engine: " DF_RC "\n", DP_RC(rc));
625 	}
626 }
627 
628 int
629 create_bdev_daos(struct spdk_bdev **bdev,
630 		 const char *name, const struct spdk_uuid *uuid,
631 		 const char *pool, const char *cont,
632 		 uint64_t num_blocks, uint32_t block_size)
633 {
634 	int rc;
635 	size_t len;
636 	struct bdev_daos *daos;
637 
638 	SPDK_NOTICELOG("%s: creating bdev_daos disk on '%s:%s'\n", name, pool, cont);
639 
640 	if (num_blocks == 0) {
641 		SPDK_ERRLOG("Disk num_blocks must be greater than 0");
642 		return -EINVAL;
643 	}
644 
645 	if (block_size % 512) {
646 		SPDK_ERRLOG("block size must be 512 bytes aligned\n");
647 		return -EINVAL;
648 	}
649 
650 	if (!name) {
651 		SPDK_ERRLOG("device name cannot be empty\n");
652 		return -EINVAL;
653 	}
654 
655 	if (!pool) {
656 		SPDK_ERRLOG("daos pool cannot be empty\n");
657 		return -EINVAL;
658 	}
659 	if (!cont) {
660 		SPDK_ERRLOG("daos cont cannot be empty\n");
661 		return -EINVAL;
662 	}
663 
664 	daos = calloc(1, sizeof(*daos));
665 	if (!daos) {
666 		SPDK_ERRLOG("calloc() failed\n");
667 		return -ENOMEM;
668 	}
669 
670 	len = strlen(pool);
671 	if (len > DAOS_PROP_LABEL_MAX_LEN) {
672 		SPDK_ERRLOG("daos pool name is too long\n");
673 		free(daos);
674 		return -EINVAL;
675 	}
676 	memcpy(daos->pool_name, pool, len);
677 
678 	len = strlen(cont);
679 	if (len > DAOS_PROP_LABEL_MAX_LEN) {
680 		SPDK_ERRLOG("daos cont name is too long\n");
681 		free(daos);
682 		return -EINVAL;
683 	}
684 	memcpy(daos->cont_name, cont, len);
685 
686 	daos->disk.name = strdup(name);
687 	daos->disk.product_name = "DAOS bdev";
688 
689 	daos->disk.write_cache = 0;
690 	daos->disk.blocklen = block_size;
691 	daos->disk.blockcnt = num_blocks;
692 
693 	if (uuid) {
694 		daos->disk.uuid = *uuid;
695 	} else {
696 		spdk_uuid_generate(&daos->disk.uuid);
697 	}
698 
699 	daos->disk.ctxt = daos;
700 	daos->disk.fn_table = &daos_fn_table;
701 	daos->disk.module = &daos_if;
702 
703 	rc = bdev_get_daos_engine();
704 	if (rc) {
705 		SPDK_ERRLOG("could not initialize DAOS engine: " DF_RC "\n", DP_RC(rc));
706 		bdev_daos_free(daos);
707 		return rc;
708 	}
709 
710 	spdk_io_device_register(daos, bdev_daos_io_channel_create_cb,
711 				bdev_daos_io_channel_destroy_cb,
712 				sizeof(struct bdev_daos_io_channel),
713 				daos->disk.name);
714 
715 
716 	rc = spdk_bdev_register(&daos->disk);
717 	if (rc) {
718 		spdk_io_device_unregister(daos, NULL);
719 		bdev_daos_free(daos);
720 		return rc;
721 	}
722 
723 	*bdev = &(daos->disk);
724 
725 	return rc;
726 }
727 
728 void
729 delete_bdev_daos(struct spdk_bdev *bdev, spdk_delete_daos_complete cb_fn, void *cb_arg)
730 {
731 	if (!bdev || bdev->module != &daos_if) {
732 		cb_fn(cb_arg, -ENODEV);
733 		return;
734 	}
735 
736 	spdk_bdev_unregister(bdev, cb_fn, cb_arg);
737 }
738 
739 static int
740 bdev_get_daos_engine(void)
741 {
742 	int rc = 0;
743 
744 	pthread_mutex_lock(&g_bdev_daos_init_mutex);
745 	if (g_bdev_daos_init_count++ > 0) {
746 		pthread_mutex_unlock(&g_bdev_daos_init_mutex);
747 		return 0;
748 	}
749 	SPDK_DEBUGLOG(bdev_daos, "initializing DAOS engine\n");
750 
751 	rc = daos_init();
752 	pthread_mutex_unlock(&g_bdev_daos_init_mutex);
753 
754 	if (rc != -DER_ALREADY && rc) {
755 		return rc;
756 	}
757 	return 0;
758 }
759 
760 static int
761 bdev_daos_put_engine(void)
762 {
763 	int rc = 0;
764 
765 	pthread_mutex_lock(&g_bdev_daos_init_mutex);
766 	if (--g_bdev_daos_init_count > 0) {
767 		pthread_mutex_unlock(&g_bdev_daos_init_mutex);
768 		return 0;
769 	}
770 	SPDK_DEBUGLOG(bdev_daos, "de-initializing DAOS engine\n");
771 
772 	rc = daos_fini();
773 	pthread_mutex_unlock(&g_bdev_daos_init_mutex);
774 
775 	return rc;
776 }
777 
778 static int
779 bdev_daos_initialize(void)
780 {
781 	/* DAOS engine and client initialization happens
782 	   during the first bdev creation */
783 	return 0;
784 }
785 
786 SPDK_LOG_REGISTER_COMPONENT(bdev_daos)
787