xref: /spdk/module/bdev/daos/bdev_daos.c (revision 1b1967bdd61daa5ec110e2ca6c73c7b38a60bb89)
1 /*   SPDX-License-Identifier: BSD-3-Clause
2  *   Copyright (c) croit GmbH.
3  *   All rights reserved.
4  */
5 
6 #include <sys/queue.h>
7 
8 #include "spdk/bdev.h"
9 #include "spdk/bdev_module.h"
10 #include "spdk/endian.h"
11 #include "spdk/env.h"
12 #include "spdk/json.h"
13 #include "spdk/thread.h"
14 #include "spdk/queue.h"
15 #include "spdk/string.h"
16 #include "spdk/stdinc.h"
17 #include "spdk/log.h"
18 
19 #include <daos.h>
20 #include <daos_event.h>
21 #include <daos_fs.h>
22 #include <daos_types.h>
23 #include <daos_pool.h>
24 #include <daos_cont.h>
25 #include <daos_errno.h>
26 
27 #include "bdev_daos.h"
28 
29 #define BDEV_DAOS_IOVECS_MAX 32
30 
31 struct bdev_daos_task {
32 	daos_event_t ev;
33 	struct spdk_thread *submit_td;
34 	struct spdk_bdev_io *bdev_io;
35 
36 	enum spdk_bdev_io_status status;
37 
38 	uint64_t offset;
39 
40 	/* DAOS version of iovec and scatter/gather */
41 	daos_size_t read_size;
42 	d_iov_t diovs[BDEV_DAOS_IOVECS_MAX];
43 	d_sg_list_t sgl;
44 };
45 
46 struct bdev_daos {
47 	struct spdk_bdev disk;
48 	daos_oclass_id_t oclass;
49 
50 	char pool_name[DAOS_PROP_MAX_LABEL_BUF_LEN];
51 	char cont_name[DAOS_PROP_MAX_LABEL_BUF_LEN];
52 
53 	struct bdev_daos_task *reset_task;
54 	struct spdk_poller    *reset_retry_timer;
55 };
56 
57 struct bdev_daos_io_channel {
58 	struct bdev_daos *disk;
59 	struct spdk_poller *poller;
60 
61 	daos_handle_t pool;
62 	daos_handle_t cont;
63 
64 	dfs_t *dfs;
65 	dfs_obj_t *obj;
66 	daos_handle_t queue;
67 };
68 
69 static uint32_t g_bdev_daos_init_count = 0;
70 static pthread_mutex_t g_bdev_daos_init_mutex = PTHREAD_MUTEX_INITIALIZER;
71 
72 static int bdev_daos_initialize(void);
73 
74 static int bdev_get_daos_engine(void);
75 static int bdev_daos_put_engine(void);
76 
77 static int
78 bdev_daos_get_ctx_size(void)
79 {
80 	return sizeof(struct bdev_daos_task);
81 }
82 
83 static struct spdk_bdev_module daos_if = {
84 	.name = "daos",
85 	.module_init = bdev_daos_initialize,
86 	.get_ctx_size = bdev_daos_get_ctx_size,
87 };
88 
89 SPDK_BDEV_MODULE_REGISTER(daos, &daos_if)
90 
91 static void
92 bdev_daos_free(struct bdev_daos *bdev_daos)
93 {
94 	if (!bdev_daos) {
95 		return;
96 	}
97 
98 	free(bdev_daos->disk.name);
99 	free(bdev_daos);
100 }
101 
102 static void
103 bdev_daos_destruct_cb(void *io_device)
104 {
105 	int rc;
106 	struct bdev_daos *daos = io_device;
107 
108 	assert(daos != NULL);
109 
110 	bdev_daos_free(daos);
111 
112 	rc = bdev_daos_put_engine();
113 	if (rc) {
114 		SPDK_ERRLOG("could not de-initialize DAOS engine: " DF_RC "\n", DP_RC(rc));
115 	}
116 }
117 
118 static int
119 bdev_daos_destruct(void *ctx)
120 {
121 	struct bdev_daos *daos = ctx;
122 
123 	SPDK_NOTICELOG("%s: destroying bdev_daos device\n", daos->disk.name);
124 
125 	spdk_io_device_unregister(daos, bdev_daos_destruct_cb);
126 
127 	return 0;
128 }
129 
130 static void
131 _bdev_daos_io_complete(void *bdev_daos_task)
132 {
133 	struct bdev_daos_task *task = bdev_daos_task;
134 
135 	SPDK_DEBUGLOG(bdev_daos, "completed IO at %#lx with status %s\n", task->offset,
136 		      task->status == SPDK_BDEV_IO_STATUS_SUCCESS ? "SUCCESS" : "FAILURE");
137 
138 	spdk_bdev_io_complete(spdk_bdev_io_from_ctx(task), task->status);
139 }
140 
141 static void
142 bdev_daos_io_complete(struct spdk_bdev_io *bdev_io, enum spdk_bdev_io_status status)
143 {
144 	struct bdev_daos_task *task = (struct bdev_daos_task *)bdev_io->driver_ctx;
145 	struct spdk_thread *current_thread = spdk_get_thread();
146 
147 	assert(task->submit_td != NULL);
148 
149 	task->status = status;
150 	if (task->submit_td != current_thread) {
151 		spdk_thread_send_msg(task->submit_td, _bdev_daos_io_complete, task);
152 	} else {
153 		_bdev_daos_io_complete(task);
154 	}
155 }
156 
157 static int64_t
158 bdev_daos_writev(struct bdev_daos *daos, struct bdev_daos_io_channel *ch,
159 		 struct bdev_daos_task *task,
160 		 struct iovec *iov, int iovcnt, uint64_t nbytes, uint64_t offset)
161 {
162 	int rc;
163 
164 	SPDK_DEBUGLOG(bdev_daos, "write %d iovs size %lu to off: %#lx\n",
165 		      iovcnt, nbytes, offset);
166 
167 	assert(ch != NULL);
168 	assert(daos != NULL);
169 	assert(task != NULL);
170 	assert(iov != NULL);
171 
172 	if (iovcnt > BDEV_DAOS_IOVECS_MAX) {
173 		SPDK_ERRLOG("iovs number [%d] exceeds max allowed limit [%d]\n", iovcnt,
174 			    BDEV_DAOS_IOVECS_MAX);
175 		return -E2BIG;
176 	}
177 
178 	if ((rc = daos_event_init(&task->ev, ch->queue, NULL))) {
179 		SPDK_ERRLOG("%s: could not initialize async event: " DF_RC "\n",
180 			    daos->disk.name, DP_RC(rc));
181 		return -EINVAL;
182 	}
183 
184 	for (int i = 0; i < iovcnt; i++, iov++) {
185 		d_iov_set(&(task->diovs[i]), iov->iov_base, iov->iov_len);
186 	}
187 
188 	task->sgl.sg_nr = iovcnt;
189 	task->sgl.sg_nr_out = 0;
190 	task->sgl.sg_iovs = task->diovs;
191 	task->offset = offset;
192 
193 	if ((rc = dfs_write(ch->dfs, ch->obj, &task->sgl, offset, &task->ev))) {
194 		SPDK_ERRLOG("%s: could not start async write: " DF_RC "\n",
195 			    daos->disk.name, DP_RC(rc));
196 		daos_event_fini(&task->ev);
197 		return -EINVAL;
198 	}
199 
200 	return nbytes;
201 }
202 
203 static int64_t
204 bdev_daos_readv(struct bdev_daos *daos, struct bdev_daos_io_channel *ch,
205 		struct bdev_daos_task *task,
206 		struct iovec *iov, int iovcnt, uint64_t nbytes, uint64_t offset)
207 {
208 	int rc;
209 
210 	SPDK_DEBUGLOG(bdev_daos, "read %d iovs size %lu to off: %#lx\n",
211 		      iovcnt, nbytes, offset);
212 
213 	assert(ch != NULL);
214 	assert(daos != NULL);
215 	assert(task != NULL);
216 	assert(iov != NULL);
217 
218 	if (iovcnt > BDEV_DAOS_IOVECS_MAX) {
219 		SPDK_ERRLOG("iovs number [%d] exceeds max allowed limit [%d]\n", iovcnt,
220 			    BDEV_DAOS_IOVECS_MAX);
221 		return -E2BIG;
222 	}
223 
224 	if ((rc = daos_event_init(&task->ev, ch->queue, NULL))) {
225 		SPDK_ERRLOG("%s: could not initialize async event: " DF_RC "\n",
226 			    daos->disk.name, DP_RC(rc));
227 		return -EINVAL;
228 	}
229 
230 	for (int i = 0; i < iovcnt; i++, iov++) {
231 		d_iov_set(&(task->diovs[i]), iov->iov_base, iov->iov_len);
232 	}
233 
234 	task->sgl.sg_nr = iovcnt;
235 	task->sgl.sg_nr_out = 0;
236 	task->sgl.sg_iovs = task->diovs;
237 	task->offset = offset;
238 
239 	if ((rc = dfs_read(ch->dfs, ch->obj, &task->sgl, offset, &task->read_size, &task->ev))) {
240 		SPDK_ERRLOG("%s: could not start async read: " DF_RC "\n",
241 			    daos->disk.name, DP_RC(rc));
242 		daos_event_fini(&task->ev);
243 		return -EINVAL;
244 	}
245 
246 	return nbytes;
247 }
248 
249 static void
250 bdev_daos_get_buf_cb(struct spdk_io_channel *ch, struct spdk_bdev_io *bdev_io,
251 		     bool success)
252 {
253 	int64_t rc;
254 	struct bdev_daos_io_channel *dch = spdk_io_channel_get_ctx(ch);
255 
256 	if (!success) {
257 		bdev_daos_io_complete(bdev_io, SPDK_BDEV_IO_STATUS_FAILED);
258 		return;
259 	}
260 
261 	rc = bdev_daos_readv((struct bdev_daos *)bdev_io->bdev->ctxt,
262 			     dch,
263 			     (struct bdev_daos_task *)bdev_io->driver_ctx,
264 			     bdev_io->u.bdev.iovs,
265 			     bdev_io->u.bdev.iovcnt,
266 			     bdev_io->u.bdev.num_blocks * bdev_io->bdev->blocklen,
267 			     bdev_io->u.bdev.offset_blocks * bdev_io->bdev->blocklen);
268 
269 	if (rc < 0) {
270 		spdk_bdev_io_complete(bdev_io, SPDK_BDEV_IO_STATUS_FAILED);
271 		return;
272 	}
273 }
274 
275 static void
276 _bdev_daos_get_io_inflight(struct spdk_io_channel_iter *i)
277 {
278 	struct spdk_io_channel *ch = spdk_io_channel_iter_get_channel(i);
279 	struct bdev_daos_io_channel *dch = spdk_io_channel_get_ctx(ch);
280 	int io_inflight = daos_eq_query(dch->queue, DAOS_EQR_WAITING, 0, NULL);
281 
282 	if (io_inflight > 0) {
283 		spdk_for_each_channel_continue(i, -1);
284 		return;
285 	}
286 
287 	spdk_for_each_channel_continue(i, 0);
288 }
289 
290 static int bdev_daos_reset_retry_timer(void *arg);
291 
292 static void
293 _bdev_daos_get_io_inflight_done(struct spdk_io_channel_iter *i, int status)
294 {
295 	struct bdev_daos *daos = spdk_io_channel_iter_get_ctx(i);
296 
297 	if (status == -1) {
298 		daos->reset_retry_timer = SPDK_POLLER_REGISTER(bdev_daos_reset_retry_timer, daos, 1000);
299 		return;
300 	}
301 
302 	spdk_bdev_io_complete(spdk_bdev_io_from_ctx(daos->reset_task), SPDK_BDEV_IO_STATUS_SUCCESS);
303 }
304 
305 static int
306 bdev_daos_reset_retry_timer(void *arg)
307 {
308 	struct bdev_daos *daos = arg;
309 
310 	if (daos->reset_retry_timer) {
311 		spdk_poller_unregister(&daos->reset_retry_timer);
312 	}
313 
314 	spdk_for_each_channel(daos,
315 			      _bdev_daos_get_io_inflight,
316 			      daos,
317 			      _bdev_daos_get_io_inflight_done);
318 
319 	return SPDK_POLLER_BUSY;
320 }
321 
322 static void
323 bdev_daos_reset(struct bdev_daos *daos, struct bdev_daos_task *task)
324 {
325 	assert(daos != NULL);
326 	assert(task != NULL);
327 
328 	daos->reset_task = task;
329 	bdev_daos_reset_retry_timer(daos);
330 }
331 
332 
333 static int64_t
334 bdev_daos_unmap(struct bdev_daos_io_channel *ch, uint64_t nbytes,
335 		uint64_t offset)
336 {
337 	SPDK_DEBUGLOG(bdev_daos, "unmap at %#lx with size %#lx\n", offset, nbytes);
338 	return dfs_punch(ch->dfs, ch->obj, offset, nbytes);
339 }
340 
341 static void
342 _bdev_daos_submit_request(struct spdk_io_channel *ch, struct spdk_bdev_io *bdev_io)
343 {
344 	struct bdev_daos_io_channel *dch = spdk_io_channel_get_ctx(ch);
345 
346 	int64_t rc;
347 	switch (bdev_io->type) {
348 	case SPDK_BDEV_IO_TYPE_READ:
349 		spdk_bdev_io_get_buf(bdev_io, bdev_daos_get_buf_cb,
350 				     bdev_io->u.bdev.num_blocks * bdev_io->bdev->blocklen);
351 		break;
352 
353 	case SPDK_BDEV_IO_TYPE_WRITE:
354 		rc = bdev_daos_writev((struct bdev_daos *)bdev_io->bdev->ctxt,
355 				      dch,
356 				      (struct bdev_daos_task *)bdev_io->driver_ctx,
357 				      bdev_io->u.bdev.iovs,
358 				      bdev_io->u.bdev.iovcnt,
359 				      bdev_io->u.bdev.num_blocks * bdev_io->bdev->blocklen,
360 				      bdev_io->u.bdev.offset_blocks * bdev_io->bdev->blocklen);
361 		if (rc < 0) {
362 			spdk_bdev_io_complete(bdev_io, SPDK_BDEV_IO_STATUS_FAILED);
363 			return;
364 		}
365 		break;
366 
367 	case SPDK_BDEV_IO_TYPE_RESET:
368 		/* Can't cancel in-flight requests, but can wait for their completions */
369 		bdev_daos_reset((struct bdev_daos *)bdev_io->bdev->ctxt,
370 				(struct bdev_daos_task *)bdev_io->driver_ctx);
371 		break;
372 
373 	case SPDK_BDEV_IO_TYPE_FLUSH:
374 		/* NOOP because DAOS requests land on PMEM and writes are persistent upon completion */
375 		spdk_bdev_io_complete(bdev_io, SPDK_BDEV_IO_STATUS_SUCCESS);
376 		break;
377 
378 	case SPDK_BDEV_IO_TYPE_UNMAP:
379 		rc = bdev_daos_unmap(dch,
380 				     bdev_io->u.bdev.num_blocks * bdev_io->bdev->blocklen,
381 				     bdev_io->u.bdev.offset_blocks * bdev_io->bdev->blocklen);
382 		if (!rc) {
383 			spdk_bdev_io_complete(bdev_io, SPDK_BDEV_IO_STATUS_SUCCESS);
384 		} else {
385 			SPDK_DEBUGLOG(bdev_daos, "%s: could not unmap: " DF_RC "\n",
386 				      dch->disk->disk.name, DP_RC((int)rc));
387 			spdk_bdev_io_complete(bdev_io, SPDK_BDEV_IO_STATUS_FAILED);
388 		}
389 
390 		break;
391 
392 	default:
393 		SPDK_ERRLOG("Wrong io type\n");
394 		spdk_bdev_io_complete(bdev_io, SPDK_BDEV_IO_STATUS_FAILED);
395 		break;
396 	}
397 }
398 
399 static void
400 bdev_daos_submit_request(struct spdk_io_channel *ch, struct spdk_bdev_io *bdev_io)
401 {
402 	struct bdev_daos_task *task = (struct bdev_daos_task *)bdev_io->driver_ctx;
403 	struct spdk_thread *submit_td = spdk_io_channel_get_thread(ch);
404 
405 	assert(task != NULL);
406 
407 	task->submit_td = submit_td;
408 	task->bdev_io = bdev_io;
409 
410 	_bdev_daos_submit_request(ch, bdev_io);
411 }
412 
413 #define POLLING_EVENTS_NUM 64
414 
415 static int
416 bdev_daos_channel_poll(void *arg)
417 {
418 	daos_event_t *evp[POLLING_EVENTS_NUM];
419 	struct bdev_daos_io_channel *ch = arg;
420 
421 	assert(ch != NULL);
422 	assert(ch->disk != NULL);
423 
424 	int rc = daos_eq_poll(ch->queue, 0, DAOS_EQ_NOWAIT,
425 			      POLLING_EVENTS_NUM, evp);
426 
427 	if (rc < 0) {
428 		SPDK_DEBUGLOG(bdev_daos, "%s: could not poll daos event queue: " DF_RC "\n",
429 			      ch->disk->disk.name, DP_RC(rc));
430 		/*
431 		 * TODO: There are cases when this is self healing, e.g.
432 		 * brief network issues, DAOS agent restarting etc.
433 		 * However, if the issue persists over some time better would be
434 		 * to remove a bdev or the whole controller
435 		 */
436 		return SPDK_POLLER_BUSY;
437 	}
438 
439 	for (int i = 0; i < rc; ++i) {
440 		struct bdev_daos_task *task = SPDK_CONTAINEROF(evp[i], struct bdev_daos_task, ev);
441 		enum spdk_bdev_io_status status = SPDK_BDEV_IO_STATUS_SUCCESS;
442 
443 		assert(task != NULL);
444 
445 		if (task->ev.ev_error != DER_SUCCESS) {
446 			status = SPDK_BDEV_IO_STATUS_FAILED;
447 		}
448 
449 		daos_event_fini(&task->ev);
450 		bdev_daos_io_complete(task->bdev_io, status);
451 	}
452 
453 	return rc > 0 ? SPDK_POLLER_BUSY : SPDK_POLLER_IDLE;
454 }
455 
456 static bool
457 bdev_daos_io_type_supported(void *ctx, enum spdk_bdev_io_type io_type)
458 {
459 	switch (io_type) {
460 	case SPDK_BDEV_IO_TYPE_READ:
461 	case SPDK_BDEV_IO_TYPE_WRITE:
462 	case SPDK_BDEV_IO_TYPE_RESET:
463 	case SPDK_BDEV_IO_TYPE_FLUSH:
464 	case SPDK_BDEV_IO_TYPE_UNMAP:
465 		return true;
466 
467 	default:
468 		return false;
469 	}
470 }
471 
472 static struct spdk_io_channel *
473 bdev_daos_get_io_channel(void *ctx)
474 {
475 	return spdk_get_io_channel(ctx);
476 }
477 
478 static void
479 bdev_daos_write_json_config(struct spdk_bdev *bdev, struct spdk_json_write_ctx *w)
480 {
481 	char uuid_str[SPDK_UUID_STRING_LEN];
482 	struct bdev_daos *daos = bdev->ctxt;
483 
484 	spdk_json_write_object_begin(w);
485 
486 	spdk_json_write_named_string(w, "method", "bdev_daos_create");
487 
488 	spdk_json_write_named_object_begin(w, "params");
489 	spdk_json_write_named_string(w, "name", bdev->name);
490 	spdk_json_write_named_string(w, "pool", daos->pool_name);
491 	spdk_json_write_named_string(w, "cont", daos->cont_name);
492 	spdk_json_write_named_uint64(w, "num_blocks", bdev->blockcnt);
493 	spdk_json_write_named_uint32(w, "block_size", bdev->blocklen);
494 	spdk_uuid_fmt_lower(uuid_str, sizeof(uuid_str), &bdev->uuid);
495 	spdk_json_write_named_string(w, "uuid", uuid_str);
496 
497 	spdk_json_write_object_end(w);
498 
499 	spdk_json_write_object_end(w);
500 }
501 
502 static const struct spdk_bdev_fn_table daos_fn_table = {
503 	.destruct		= bdev_daos_destruct,
504 	.submit_request		= bdev_daos_submit_request,
505 	.io_type_supported	= bdev_daos_io_type_supported,
506 	.get_io_channel		= bdev_daos_get_io_channel,
507 	.write_config_json	= bdev_daos_write_json_config,
508 };
509 
510 static int
511 bdev_daos_io_channel_setup_daos(struct bdev_daos_io_channel *ch)
512 {
513 	int rc = 0;
514 	struct bdev_daos *daos = ch->disk;
515 	daos_pool_info_t pinfo;
516 	daos_cont_info_t cinfo;
517 
518 	int fd_oflag = O_CREAT | O_RDWR;
519 	mode_t mode = S_IFREG | S_IRWXU | S_IRWXG | S_IRWXO;
520 
521 	rc = bdev_get_daos_engine();
522 	if (rc) {
523 		SPDK_ERRLOG("could not initialize DAOS engine: " DF_RC "\n", DP_RC(rc));
524 		return rc;
525 	}
526 
527 	SPDK_DEBUGLOG(bdev_daos, "connecting to daos pool '%s'\n", daos->pool_name);
528 	if ((rc = daos_pool_connect(daos->pool_name, NULL, DAOS_PC_RW, &ch->pool, &pinfo, NULL))) {
529 		SPDK_ERRLOG("%s: could not connect to daos pool: " DF_RC "\n",
530 			    daos->disk.name, DP_RC(rc));
531 		return rc;
532 	}
533 	SPDK_DEBUGLOG(bdev_daos, "connecting to daos container '%s'\n", daos->cont_name);
534 	if ((rc = daos_cont_open(ch->pool, daos->cont_name, DAOS_COO_RW, &ch->cont, &cinfo, NULL))) {
535 		SPDK_ERRLOG("%s: could not open daos container: " DF_RC "\n",
536 			    daos->disk.name, DP_RC(rc));
537 		goto cleanup_pool;
538 	}
539 	SPDK_DEBUGLOG(bdev_daos, "mounting daos dfs\n");
540 	if ((rc = dfs_mount(ch->pool, ch->cont, O_RDWR, &ch->dfs))) {
541 		SPDK_ERRLOG("%s: could not mount daos dfs: " DF_RC "\n",
542 			    daos->disk.name, DP_RC(rc));
543 		goto cleanup_cont;
544 	}
545 	SPDK_DEBUGLOG(bdev_daos, "opening dfs object\n");
546 	if ((rc = dfs_open(ch->dfs, NULL, daos->disk.name, mode, fd_oflag, daos->oclass,
547 			   0, NULL, &ch->obj))) {
548 		SPDK_ERRLOG("%s: could not open dfs object: " DF_RC "\n",
549 			    daos->disk.name, DP_RC(rc));
550 		goto cleanup_mount;
551 	}
552 	if ((rc = daos_eq_create(&ch->queue))) {
553 		SPDK_ERRLOG("%s: could not create daos event queue: " DF_RC "\n",
554 			    daos->disk.name, DP_RC(rc));
555 		goto cleanup_obj;
556 	}
557 
558 	return 0;
559 
560 cleanup_obj:
561 	dfs_release(ch->obj);
562 cleanup_mount:
563 	dfs_umount(ch->dfs);
564 cleanup_cont:
565 	daos_cont_close(ch->cont, NULL);
566 cleanup_pool:
567 	daos_pool_disconnect(ch->pool, NULL);
568 
569 	return rc;
570 }
571 
572 static int
573 bdev_daos_io_channel_create_cb(void *io_device, void *ctx_buf)
574 {
575 	struct bdev_daos_io_channel *ch = ctx_buf;
576 
577 	ch->disk = io_device;
578 
579 	if (bdev_daos_io_channel_setup_daos(ch)) {
580 		return -EINVAL;
581 	}
582 
583 	SPDK_DEBUGLOG(bdev_daos, "%s: starting daos event queue poller\n",
584 		      ch->disk->disk.name);
585 
586 	ch->poller = SPDK_POLLER_REGISTER(bdev_daos_channel_poll, ch, 0);
587 
588 	return 0;
589 }
590 
591 static void
592 bdev_daos_io_channel_destroy_cb(void *io_device, void *ctx_buf)
593 {
594 	int rc;
595 	struct bdev_daos_io_channel *ch = ctx_buf;
596 
597 	SPDK_DEBUGLOG(bdev_daos, "stopping daos event queue poller\n");
598 
599 	spdk_poller_unregister(&ch->poller);
600 
601 	if ((rc = daos_eq_destroy(ch->queue, DAOS_EQ_DESTROY_FORCE))) {
602 		SPDK_ERRLOG("could not destroy daos event queue: " DF_RC "\n", DP_RC(rc));
603 	}
604 	if ((rc = dfs_release(ch->obj))) {
605 		SPDK_ERRLOG("could not release dfs object: " DF_RC "\n", DP_RC(rc));
606 	}
607 	if ((rc = dfs_umount(ch->dfs))) {
608 		SPDK_ERRLOG("could not unmount dfs: " DF_RC "\n", DP_RC(rc));
609 	}
610 	if ((rc = daos_cont_close(ch->cont, NULL))) {
611 		SPDK_ERRLOG("could not close container: " DF_RC "\n", DP_RC(rc));
612 	}
613 	if ((rc = daos_pool_disconnect(ch->pool, NULL))) {
614 		SPDK_ERRLOG("could not disconnect from pool: " DF_RC "\n", DP_RC(rc));
615 	}
616 	rc = bdev_daos_put_engine();
617 	if (rc) {
618 		SPDK_ERRLOG("could not de-initialize DAOS engine: " DF_RC "\n", DP_RC(rc));
619 	}
620 }
621 
622 int
623 create_bdev_daos(struct spdk_bdev **bdev,
624 		 const char *name, const struct spdk_uuid *uuid,
625 		 const char *pool, const char *cont, const char *oclass,
626 		 uint64_t num_blocks, uint32_t block_size)
627 {
628 	int rc;
629 	size_t len;
630 	struct bdev_daos *daos;
631 	struct bdev_daos_io_channel ch = {};
632 
633 	SPDK_NOTICELOG("%s: creating bdev_daos disk on '%s:%s'\n", name, pool, cont);
634 
635 	if (num_blocks == 0) {
636 		SPDK_ERRLOG("Disk num_blocks must be greater than 0");
637 		return -EINVAL;
638 	}
639 
640 	if (block_size % 512) {
641 		SPDK_ERRLOG("block size must be 512 bytes aligned\n");
642 		return -EINVAL;
643 	}
644 
645 	if (!name) {
646 		SPDK_ERRLOG("device name cannot be empty\n");
647 		return -EINVAL;
648 	}
649 
650 	if (!pool) {
651 		SPDK_ERRLOG("daos pool cannot be empty\n");
652 		return -EINVAL;
653 	}
654 	if (!cont) {
655 		SPDK_ERRLOG("daos cont cannot be empty\n");
656 		return -EINVAL;
657 	}
658 
659 	daos = calloc(1, sizeof(*daos));
660 	if (!daos) {
661 		SPDK_ERRLOG("calloc() failed\n");
662 		return -ENOMEM;
663 	}
664 
665 	if (!oclass) {
666 		oclass = "SX"; /* Max throughput by default */
667 	}
668 	daos->oclass = daos_oclass_name2id(oclass);
669 	if (daos->oclass == OC_UNKNOWN) {
670 		SPDK_ERRLOG("could not parse daos oclass: '%s'\n", oclass);
671 		free(daos);
672 		return -EINVAL;
673 	}
674 
675 	len = strlen(pool);
676 	if (len > DAOS_PROP_LABEL_MAX_LEN) {
677 		SPDK_ERRLOG("daos pool name is too long\n");
678 		free(daos);
679 		return -EINVAL;
680 	}
681 	memcpy(daos->pool_name, pool, len);
682 
683 	len = strlen(cont);
684 	if (len > DAOS_PROP_LABEL_MAX_LEN) {
685 		SPDK_ERRLOG("daos cont name is too long\n");
686 		free(daos);
687 		return -EINVAL;
688 	}
689 	memcpy(daos->cont_name, cont, len);
690 
691 	daos->disk.name = strdup(name);
692 	daos->disk.product_name = "DAOS bdev";
693 
694 	daos->disk.write_cache = 0;
695 	daos->disk.blocklen = block_size;
696 	daos->disk.blockcnt = num_blocks;
697 
698 	if (uuid) {
699 		daos->disk.uuid = *uuid;
700 	}
701 
702 	daos->disk.ctxt = daos;
703 	daos->disk.fn_table = &daos_fn_table;
704 	daos->disk.module = &daos_if;
705 
706 	rc = bdev_get_daos_engine();
707 	if (rc) {
708 		SPDK_ERRLOG("could not initialize DAOS engine: " DF_RC "\n", DP_RC(rc));
709 		bdev_daos_free(daos);
710 		return rc;
711 	}
712 
713 	/* We try to connect to the DAOS container during channel creation, so simulate
714 	 * creating a channel here, so that we can return a failure when the DAOS bdev
715 	 * is created, instead of finding it out later when the first channel is created
716 	 * and leaving unusable bdev registered.
717 	 */
718 	rc = bdev_daos_io_channel_create_cb(daos, &ch);
719 	if (rc) {
720 		SPDK_ERRLOG("'%s' could not initialize io-channel: %s", name, strerror(-rc));
721 		bdev_daos_free(daos);
722 		return rc;
723 	}
724 	bdev_daos_io_channel_destroy_cb(daos, &ch);
725 
726 	spdk_io_device_register(daos, bdev_daos_io_channel_create_cb,
727 				bdev_daos_io_channel_destroy_cb,
728 				sizeof(struct bdev_daos_io_channel),
729 				daos->disk.name);
730 
731 
732 	rc = spdk_bdev_register(&daos->disk);
733 	if (rc) {
734 		spdk_io_device_unregister(daos, NULL);
735 		bdev_daos_free(daos);
736 		return rc;
737 	}
738 
739 	*bdev = &(daos->disk);
740 
741 	return rc;
742 }
743 
744 static void
745 dummy_bdev_event_cb(enum spdk_bdev_event_type type, struct spdk_bdev *bdev, void *ctx)
746 {
747 }
748 
749 int
750 bdev_daos_resize(const char *name, const uint64_t new_size_in_mb)
751 {
752 	int rc = 0;
753 	struct spdk_bdev_desc *desc;
754 	struct spdk_bdev *bdev;
755 	struct spdk_io_channel *ch;
756 	struct bdev_daos_io_channel *dch;
757 	uint64_t new_size_in_byte;
758 	uint64_t current_size_in_mb;
759 
760 	rc = spdk_bdev_open_ext(name, false, dummy_bdev_event_cb, NULL, &desc);
761 	if (rc != 0) {
762 		return rc;
763 	}
764 
765 	bdev = spdk_bdev_desc_get_bdev(desc);
766 	if (bdev->module != &daos_if) {
767 		rc = -EINVAL;
768 		goto exit;
769 	}
770 
771 	current_size_in_mb = bdev->blocklen * bdev->blockcnt / (1024 * 1024);
772 	if (current_size_in_mb > new_size_in_mb) {
773 		SPDK_ERRLOG("The new bdev size must be larger than current bdev size.\n");
774 		rc = -EINVAL;
775 		goto exit;
776 	}
777 
778 	ch = bdev_daos_get_io_channel(bdev);
779 	dch = spdk_io_channel_get_ctx(ch);
780 	new_size_in_byte = new_size_in_mb * 1024 * 1024;
781 
782 	rc = dfs_punch(dch->dfs, dch->obj, new_size_in_byte, DFS_MAX_FSIZE);
783 	spdk_put_io_channel(ch);
784 	if (rc != 0) {
785 		SPDK_ERRLOG("failed to resize daos bdev: " DF_RC "\n", DP_RC(rc));
786 		rc = -EINTR;
787 		goto exit;
788 	}
789 
790 	SPDK_NOTICELOG("DAOS bdev device is resized: bdev name %s, old block count %" PRIu64
791 		       ", new block count %"
792 		       PRIu64 "\n",
793 		       bdev->name,
794 		       bdev->blockcnt,
795 		       new_size_in_byte / bdev->blocklen);
796 	rc = spdk_bdev_notify_blockcnt_change(bdev, new_size_in_byte / bdev->blocklen);
797 	if (rc != 0) {
798 		SPDK_ERRLOG("failed to notify block cnt change.\n");
799 	}
800 
801 exit:
802 	spdk_bdev_close(desc);
803 	return rc;
804 }
805 
806 void
807 delete_bdev_daos(const char *bdev_name, spdk_bdev_unregister_cb cb_fn, void *cb_arg)
808 {
809 	int rc;
810 
811 	rc = spdk_bdev_unregister_by_name(bdev_name, &daos_if, cb_fn, cb_arg);
812 	if (rc != 0) {
813 		cb_fn(cb_arg, rc);
814 	}
815 }
816 
817 static int
818 bdev_get_daos_engine(void)
819 {
820 	int rc = 0;
821 
822 	pthread_mutex_lock(&g_bdev_daos_init_mutex);
823 	if (g_bdev_daos_init_count++ > 0) {
824 		pthread_mutex_unlock(&g_bdev_daos_init_mutex);
825 		return 0;
826 	}
827 	SPDK_DEBUGLOG(bdev_daos, "initializing DAOS engine\n");
828 
829 	rc = daos_init();
830 	pthread_mutex_unlock(&g_bdev_daos_init_mutex);
831 
832 	if (rc != -DER_ALREADY && rc) {
833 		return rc;
834 	}
835 	return 0;
836 }
837 
838 static int
839 bdev_daos_put_engine(void)
840 {
841 	int rc = 0;
842 
843 	pthread_mutex_lock(&g_bdev_daos_init_mutex);
844 	if (--g_bdev_daos_init_count > 0) {
845 		pthread_mutex_unlock(&g_bdev_daos_init_mutex);
846 		return 0;
847 	}
848 	SPDK_DEBUGLOG(bdev_daos, "de-initializing DAOS engine\n");
849 
850 	rc = daos_fini();
851 	pthread_mutex_unlock(&g_bdev_daos_init_mutex);
852 
853 	return rc;
854 }
855 
856 static int
857 bdev_daos_initialize(void)
858 {
859 	/* DAOS engine and client initialization happens
860 	   during the first bdev creation */
861 	return 0;
862 }
863 
864 SPDK_LOG_REGISTER_COMPONENT(bdev_daos)
865