xref: /spdk/module/bdev/ftl/bdev_ftl.c (revision 02e00efc878bf58046830c28dfe3b417597ef68c)
1 /*   SPDX-License-Identifier: BSD-3-Clause
2  *   Copyright (C) 2020 Intel Corporation.
3  *   All rights reserved.
4  *   Copyright 2023 Solidigm All Rights Reserved
5  */
6 
7 #include "spdk/stdinc.h"
8 #include "spdk/bdev.h"
9 #include "spdk/env.h"
10 #include "spdk/thread.h"
11 #include "spdk/json.h"
12 #include "spdk/string.h"
13 #include "spdk/likely.h"
14 #include "spdk/util.h"
15 #include "spdk/string.h"
16 #include "spdk/ftl.h"
17 #include "spdk/log.h"
18 
19 #include "bdev_ftl.h"
20 
21 struct ftl_bdev {
22 	struct spdk_bdev	bdev;
23 	struct spdk_ftl_dev	*dev;
24 	ftl_bdev_init_fn	init_cb;
25 	void			*init_arg;
26 	int			rc;
27 	struct spdk_bdev_desc	*base_bdev_desc;
28 	struct spdk_bdev_desc	*cache_bdev_desc;
29 };
30 
31 struct bdev_ftl_action {
32 	struct spdk_bdev_desc	*ftl_bdev_desc;
33 	struct ftl_bdev		*ftl_bdev_dev;
34 	spdk_ftl_fn		cb_fn;
35 	void			*cb_arg;
36 	int			rc;
37 	size_t			ctx_size;
38 	char			ctx[0];
39 };
40 
41 struct ftl_deferred_init {
42 	struct spdk_ftl_conf		conf;
43 
44 	LIST_ENTRY(ftl_deferred_init)	entry;
45 };
46 
47 static LIST_HEAD(, ftl_deferred_init)	g_deferred_init = LIST_HEAD_INITIALIZER(g_deferred_init);
48 
49 static int bdev_ftl_initialize(void);
50 static void bdev_ftl_finish(void);
51 static void bdev_ftl_examine(struct spdk_bdev *bdev);
52 
53 static void bdev_ftl_action_finish_cb(void *cb_arg, int status);
54 static struct bdev_ftl_action *bdev_ftl_action_start(const char *bdev_name,
55 		size_t ctx_size, spdk_ftl_fn cb_fn, void *cb_arg);
56 static void bdev_ftl_action_finish(struct bdev_ftl_action *action);
57 
58 static int
59 bdev_ftl_get_ctx_size(void)
60 {
61 	return spdk_ftl_io_size();
62 }
63 
64 static struct spdk_bdev_module g_ftl_if = {
65 	.name		= "ftl",
66 	.module_init	= bdev_ftl_initialize,
67 	.module_fini	= bdev_ftl_finish,
68 	.examine_disk	= bdev_ftl_examine,
69 	.get_ctx_size	= bdev_ftl_get_ctx_size,
70 };
71 
72 SPDK_BDEV_MODULE_REGISTER(ftl, &g_ftl_if)
73 
74 static void
75 bdev_ftl_free(struct ftl_bdev *ftl_bdev)
76 {
77 	spdk_bdev_close(ftl_bdev->base_bdev_desc);
78 	spdk_bdev_close(ftl_bdev->cache_bdev_desc);
79 	free(ftl_bdev->bdev.name);
80 	free(ftl_bdev);
81 }
82 
83 static void
84 bdev_ftl_dev_free_cb(void *ctx, int status)
85 {
86 	struct ftl_bdev *ftl_bdev = ctx;
87 
88 	spdk_bdev_destruct_done(&ftl_bdev->bdev, status);
89 	bdev_ftl_free(ftl_bdev);
90 }
91 
92 static int
93 bdev_ftl_destruct(void *ctx)
94 {
95 	struct ftl_bdev *ftl_bdev = ctx;
96 
97 	spdk_ftl_dev_free(ftl_bdev->dev, bdev_ftl_dev_free_cb, ftl_bdev);
98 
99 	/* return 1 to indicate that the destruction is asynchronous */
100 	return 1;
101 }
102 
103 static void
104 bdev_ftl_cb(void *arg, int rc)
105 {
106 	struct spdk_bdev_io *bdev_io = arg;
107 	enum spdk_bdev_io_status status;
108 
109 	switch (rc) {
110 	case 0:
111 		status = SPDK_BDEV_IO_STATUS_SUCCESS;
112 		break;
113 	case -EAGAIN:
114 	case -ENOMEM:
115 		status = SPDK_BDEV_IO_STATUS_NOMEM;
116 		break;
117 	default:
118 		status = SPDK_BDEV_IO_STATUS_FAILED;
119 		break;
120 	}
121 
122 	spdk_bdev_io_complete(bdev_io, status);
123 }
124 
125 static void
126 bdev_ftl_get_buf_cb(struct spdk_io_channel *ch, struct spdk_bdev_io *bdev_io,
127 		    bool success)
128 {
129 	struct ftl_bdev *ftl_bdev;
130 	int rc;
131 
132 	ftl_bdev = bdev_io->bdev->ctxt;
133 
134 	if (!success) {
135 		spdk_bdev_io_complete(bdev_io, SPDK_BDEV_IO_STATUS_FAILED);
136 		return;
137 	}
138 
139 	rc = spdk_ftl_readv(ftl_bdev->dev, (struct ftl_io *)bdev_io->driver_ctx,
140 			    ch,
141 			    bdev_io->u.bdev.offset_blocks,
142 			    bdev_io->u.bdev.num_blocks,
143 			    bdev_io->u.bdev.iovs, bdev_io->u.bdev.iovcnt, bdev_ftl_cb, bdev_io);
144 
145 	if (spdk_unlikely(rc != 0)) {
146 		bdev_ftl_cb(bdev_io, rc);
147 	}
148 }
149 
150 static int
151 _bdev_ftl_submit_request(struct spdk_io_channel *ch, struct spdk_bdev_io *bdev_io)
152 {
153 	struct ftl_bdev *ftl_bdev = (struct ftl_bdev *)bdev_io->bdev->ctxt;
154 
155 	switch (bdev_io->type) {
156 	case SPDK_BDEV_IO_TYPE_READ:
157 		spdk_bdev_io_get_buf(bdev_io, bdev_ftl_get_buf_cb,
158 				     bdev_io->u.bdev.num_blocks * bdev_io->bdev->blocklen);
159 		return 0;
160 
161 	case SPDK_BDEV_IO_TYPE_WRITE:
162 		return spdk_ftl_writev(ftl_bdev->dev, (struct ftl_io *)bdev_io->driver_ctx,
163 				       ch, bdev_io->u.bdev.offset_blocks,
164 				       bdev_io->u.bdev.num_blocks, bdev_io->u.bdev.iovs,
165 				       bdev_io->u.bdev.iovcnt, bdev_ftl_cb, bdev_io);
166 
167 	case SPDK_BDEV_IO_TYPE_UNMAP:
168 		return spdk_ftl_unmap(ftl_bdev->dev, (struct ftl_io *)bdev_io->driver_ctx,
169 				      ch, bdev_io->u.bdev.offset_blocks,
170 				      bdev_io->u.bdev.num_blocks, bdev_ftl_cb, bdev_io);
171 	case SPDK_BDEV_IO_TYPE_FLUSH:
172 		spdk_bdev_io_complete(bdev_io, SPDK_BDEV_IO_STATUS_SUCCESS);
173 		return 0;
174 	default:
175 		return -ENOTSUP;
176 	}
177 }
178 
179 static void
180 bdev_ftl_submit_request(struct spdk_io_channel *ch, struct spdk_bdev_io *bdev_io)
181 {
182 	int rc = _bdev_ftl_submit_request(ch, bdev_io);
183 
184 	if (spdk_unlikely(rc != 0)) {
185 		bdev_ftl_cb(bdev_io, rc);
186 	}
187 }
188 
189 static bool
190 bdev_ftl_io_type_supported(void *ctx, enum spdk_bdev_io_type io_type)
191 {
192 	switch (io_type) {
193 	case SPDK_BDEV_IO_TYPE_READ:
194 	case SPDK_BDEV_IO_TYPE_WRITE:
195 	case SPDK_BDEV_IO_TYPE_FLUSH:
196 	case SPDK_BDEV_IO_TYPE_UNMAP:
197 		return true;
198 	default:
199 		return false;
200 	}
201 }
202 
203 static struct spdk_io_channel *
204 bdev_ftl_get_io_channel(void *ctx)
205 {
206 	struct ftl_bdev *ftl_bdev = ctx;
207 
208 	return spdk_ftl_get_io_channel(ftl_bdev->dev);
209 }
210 
211 static void
212 bdev_ftl_write_config_json(struct spdk_bdev *bdev, struct spdk_json_write_ctx *w)
213 {
214 	struct ftl_bdev *ftl_bdev = bdev->ctxt;
215 	struct spdk_ftl_conf conf;
216 	char uuid[SPDK_UUID_STRING_LEN];
217 
218 	spdk_ftl_dev_get_conf(ftl_bdev->dev, &conf, sizeof(conf));
219 
220 	spdk_json_write_object_begin(w);
221 
222 	spdk_json_write_named_string(w, "method", "bdev_ftl_create");
223 
224 	spdk_json_write_named_object_begin(w, "params");
225 	spdk_json_write_named_string(w, "name", ftl_bdev->bdev.name);
226 
227 	spdk_json_write_named_uint64(w, "overprovisioning", conf.overprovisioning);
228 	spdk_json_write_named_uint64(w, "l2p_dram_limit", conf.l2p_dram_limit);
229 
230 	if (conf.core_mask) {
231 		spdk_json_write_named_string(w, "core_mask", conf.core_mask);
232 	}
233 
234 	spdk_uuid_fmt_lower(uuid, sizeof(uuid), &conf.uuid);
235 	spdk_json_write_named_string(w, "uuid", uuid);
236 
237 	spdk_json_write_named_bool(w, "fast_shutdown", conf.fast_shutdown);
238 
239 	spdk_json_write_named_string(w, "base_bdev", conf.base_bdev);
240 
241 	if (conf.cache_bdev) {
242 		spdk_json_write_named_string(w, "cache", conf.cache_bdev);
243 	}
244 
245 	spdk_json_write_object_end(w);
246 	spdk_json_write_object_end(w);
247 }
248 
249 static int
250 bdev_ftl_dump_info_json(void *ctx, struct spdk_json_write_ctx *w)
251 {
252 	struct ftl_bdev *ftl_bdev = ctx;
253 	struct spdk_ftl_attrs attrs;
254 	struct spdk_ftl_conf conf;
255 
256 	spdk_ftl_dev_get_attrs(ftl_bdev->dev, &attrs, sizeof(attrs));
257 	spdk_ftl_dev_get_conf(ftl_bdev->dev, &conf, sizeof(conf));
258 
259 	spdk_json_write_named_object_begin(w, "ftl");
260 
261 	spdk_json_write_named_string(w, "base_bdev", conf.base_bdev);
262 
263 	if (conf.cache_bdev) {
264 		spdk_json_write_named_string(w, "cache", conf.cache_bdev);
265 	}
266 
267 	/* ftl */
268 	spdk_json_write_object_end(w);
269 
270 	return 0;
271 }
272 
273 static const struct spdk_bdev_fn_table ftl_fn_table = {
274 	.destruct		= bdev_ftl_destruct,
275 	.submit_request		= bdev_ftl_submit_request,
276 	.io_type_supported	= bdev_ftl_io_type_supported,
277 	.get_io_channel		= bdev_ftl_get_io_channel,
278 	.write_config_json	= bdev_ftl_write_config_json,
279 	.dump_info_json		= bdev_ftl_dump_info_json,
280 };
281 
282 static void
283 bdev_ftl_create_err_complete(struct ftl_bdev *ftl_bdev)
284 {
285 	ftl_bdev_init_fn init_cb = ftl_bdev->init_cb;
286 	void *init_arg = ftl_bdev->init_arg;
287 	int rc = ftl_bdev->rc;
288 
289 	bdev_ftl_free(ftl_bdev);
290 
291 	assert(rc);
292 	init_cb(NULL, init_arg, rc);
293 }
294 
295 static void
296 bdev_ftl_create_err_cleanup_cb(void *ctx, int status)
297 {
298 	struct ftl_bdev *ftl_bdev = ctx;
299 
300 	if (status) {
301 		SPDK_ERRLOG("Fatal ERROR of FTL cleanup, name %s\n", ftl_bdev->bdev.name);
302 	}
303 
304 	bdev_ftl_create_err_complete(ftl_bdev);
305 }
306 
307 static void
308 bdev_ftl_create_cb(struct spdk_ftl_dev *dev, void *ctx, int status)
309 {
310 	struct ftl_bdev		*ftl_bdev = ctx;
311 	struct ftl_bdev_info	info = {};
312 	struct spdk_ftl_attrs	attrs;
313 	struct spdk_ftl_conf	conf;
314 	ftl_bdev_init_fn	init_cb = ftl_bdev->init_cb;
315 	void			*init_arg = ftl_bdev->init_arg;
316 
317 	if (status) {
318 		SPDK_ERRLOG("Failed to create FTL device (%d)\n", status);
319 		ftl_bdev->rc = status;
320 		goto error;
321 	}
322 
323 	spdk_ftl_dev_get_attrs(dev, &attrs, sizeof(attrs));
324 	spdk_ftl_dev_get_conf(dev, &conf, sizeof(conf));
325 
326 	ftl_bdev->dev = dev;
327 	ftl_bdev->bdev.product_name = "FTL disk";
328 	ftl_bdev->bdev.write_cache = 0;
329 	ftl_bdev->bdev.blocklen = attrs.block_size;
330 	ftl_bdev->bdev.blockcnt = attrs.num_blocks;
331 	ftl_bdev->bdev.uuid = conf.uuid;
332 	ftl_bdev->bdev.optimal_io_boundary = attrs.optimum_io_size;
333 	ftl_bdev->bdev.split_on_optimal_io_boundary = true;
334 
335 	SPDK_DEBUGLOG(bdev_ftl, "Creating bdev %s:\n", ftl_bdev->bdev.name);
336 	SPDK_DEBUGLOG(bdev_ftl, "\tblock_len:\t%zu\n", attrs.block_size);
337 	SPDK_DEBUGLOG(bdev_ftl, "\tnum_blocks:\t%"PRIu64"\n", attrs.num_blocks);
338 
339 	ftl_bdev->bdev.ctxt = ftl_bdev;
340 	ftl_bdev->bdev.fn_table = &ftl_fn_table;
341 	ftl_bdev->bdev.module = &g_ftl_if;
342 
343 	status = spdk_bdev_register(&ftl_bdev->bdev);
344 	if (status) {
345 		ftl_bdev->rc = status;
346 		goto error;
347 	}
348 
349 	info.name = ftl_bdev->bdev.name;
350 	info.uuid = ftl_bdev->bdev.uuid;
351 
352 	init_cb(&info, init_arg, 0);
353 	return;
354 
355 error:
356 	if (ftl_bdev->dev) {
357 		/* Cleanup all FTL */
358 		spdk_ftl_dev_set_fast_shutdown(ftl_bdev->dev, false);
359 
360 		/* FTL was created, but we have got an error, so we need to delete it */
361 		spdk_ftl_dev_free(dev, bdev_ftl_create_err_cleanup_cb, ftl_bdev);
362 	} else {
363 		bdev_ftl_create_err_complete(ftl_bdev);
364 	}
365 }
366 
367 static void
368 bdev_ftl_defer_free(struct ftl_deferred_init *init)
369 {
370 	spdk_ftl_conf_deinit(&init->conf);
371 	free(init);
372 }
373 
374 int
375 bdev_ftl_defer_init(const struct spdk_ftl_conf *conf)
376 {
377 	struct ftl_deferred_init *init;
378 	int rc;
379 
380 	init = calloc(1, sizeof(*init));
381 	if (!init) {
382 		return -ENOMEM;
383 	}
384 
385 	rc = spdk_ftl_conf_copy(&init->conf, conf);
386 	if (rc) {
387 		free(init);
388 		return -ENOMEM;
389 	}
390 
391 	LIST_INSERT_HEAD(&g_deferred_init, init, entry);
392 
393 	return 0;
394 }
395 
396 static void
397 bdev_ftl_create_bdev_event_cb(enum spdk_bdev_event_type type, struct spdk_bdev *bdev, void *ctx)
398 {
399 }
400 
401 int
402 bdev_ftl_create_bdev(const struct spdk_ftl_conf *conf, ftl_bdev_init_fn cb, void *cb_arg)
403 {
404 	struct ftl_bdev *ftl_bdev;
405 	struct spdk_bdev_desc *base_bdev_desc, *cache_bdev_desc;
406 	int rc;
407 
408 	rc = spdk_bdev_open_ext(conf->base_bdev, false, bdev_ftl_create_bdev_event_cb, NULL,
409 				&base_bdev_desc);
410 	if (rc) {
411 		return rc;
412 	}
413 	rc = spdk_bdev_open_ext(conf->cache_bdev, false, bdev_ftl_create_bdev_event_cb, NULL,
414 				&cache_bdev_desc);
415 	if (rc) {
416 		spdk_bdev_close(base_bdev_desc);
417 		return rc;
418 	}
419 
420 	ftl_bdev = calloc(1, sizeof(*ftl_bdev));
421 	if (!ftl_bdev) {
422 		SPDK_ERRLOG("Could not allocate ftl_bdev\n");
423 		spdk_bdev_close(base_bdev_desc);
424 		spdk_bdev_close(cache_bdev_desc);
425 		return -ENOMEM;
426 	}
427 
428 	ftl_bdev->base_bdev_desc = base_bdev_desc;
429 	ftl_bdev->cache_bdev_desc = cache_bdev_desc;
430 
431 	ftl_bdev->bdev.name = strdup(conf->name);
432 	if (!ftl_bdev->bdev.name) {
433 		rc = -ENOMEM;
434 		goto error;
435 	}
436 
437 	ftl_bdev->init_cb = cb;
438 	ftl_bdev->init_arg = cb_arg;
439 
440 	rc = spdk_ftl_dev_init(conf, bdev_ftl_create_cb, ftl_bdev);
441 	if (rc) {
442 		SPDK_ERRLOG("Could not create FTL device\n");
443 		goto error;
444 	}
445 
446 	return 0;
447 
448 error:
449 	bdev_ftl_free(ftl_bdev);
450 	return rc;
451 }
452 
453 static int
454 bdev_ftl_initialize(void)
455 {
456 	return spdk_ftl_init();
457 }
458 
459 static void
460 bdev_ftl_event_cb(enum spdk_bdev_event_type type, struct spdk_bdev *bdev, void *ctx)
461 {
462 }
463 
464 void
465 bdev_ftl_delete_bdev(const char *name, bool fast_shutdown, spdk_bdev_unregister_cb cb_fn,
466 		     void *cb_arg)
467 {
468 	struct spdk_bdev_desc	*ftl_bdev_desc;
469 	struct spdk_bdev *bdev;
470 	struct ftl_bdev *ftl;
471 	int rc;
472 
473 	rc = spdk_bdev_open_ext(name, false, bdev_ftl_event_cb, NULL, &ftl_bdev_desc);
474 
475 	if (rc) {
476 		goto not_found;
477 	}
478 
479 	bdev = spdk_bdev_desc_get_bdev(ftl_bdev_desc);
480 
481 	if (bdev->module != &g_ftl_if) {
482 		goto bdev_opened;
483 	}
484 
485 	ftl = bdev->ctxt;
486 	assert(ftl);
487 	spdk_ftl_dev_set_fast_shutdown(ftl->dev, fast_shutdown);
488 	spdk_bdev_close(ftl_bdev_desc);
489 
490 	rc = spdk_bdev_unregister_by_name(name, &g_ftl_if, cb_fn, cb_arg);
491 	if (rc) {
492 		cb_fn(cb_arg, rc);
493 	}
494 
495 	return;
496 bdev_opened:
497 	spdk_bdev_close(ftl_bdev_desc);
498 not_found:
499 	cb_fn(cb_arg, -ENODEV);
500 }
501 
502 void
503 bdev_ftl_unmap(const char *name, uint64_t lba, uint64_t num_blocks, spdk_ftl_fn cb_fn,
504 	       void *cb_arg)
505 {
506 	struct bdev_ftl_action *action;
507 
508 	action = bdev_ftl_action_start(name, 0, cb_fn, cb_arg);
509 	if (!action) {
510 		return;
511 	}
512 
513 	/* It's ok to pass NULL as IO channel - FTL will detect this and use it's internal IO channel for management operations */
514 	action->rc = spdk_ftl_unmap(action->ftl_bdev_dev->dev, NULL, NULL, lba, num_blocks,
515 				    bdev_ftl_action_finish_cb, action);
516 	if (action->rc) {
517 		bdev_ftl_action_finish(action);
518 	}
519 }
520 
521 static void
522 bdev_ftl_get_stats_cb(struct ftl_stats *stats, void *cb_arg)
523 {
524 	struct bdev_ftl_action *action = cb_arg;
525 
526 	bdev_ftl_action_finish(action);
527 }
528 
529 void
530 bdev_ftl_get_stats(const char *name, spdk_ftl_fn cb, struct rpc_ftl_stats_ctx *ftl_stats_ctx)
531 {
532 	struct bdev_ftl_action *action;
533 
534 	action = bdev_ftl_action_start(name, 0, cb, ftl_stats_ctx);
535 	if (!action) {
536 		return;
537 	}
538 	ftl_stats_ctx->ftl_bdev_desc = action->ftl_bdev_desc;
539 	action->rc = spdk_ftl_get_stats(action->ftl_bdev_dev->dev, &ftl_stats_ctx->ftl_stats,
540 					bdev_ftl_get_stats_cb, action);
541 	if (action->rc) {
542 		bdev_ftl_action_finish(action);
543 	}
544 }
545 
546 void
547 bdev_ftl_get_properties(const char *name, spdk_ftl_fn cb_fn, struct spdk_jsonrpc_request *request)
548 {
549 	struct bdev_ftl_action *action;
550 
551 	action = bdev_ftl_action_start(name, 0, cb_fn, request);
552 	if (!action) {
553 		return;
554 	}
555 
556 	action->rc = spdk_ftl_get_properties(action->ftl_bdev_dev->dev, request,
557 					     bdev_ftl_action_finish_cb, action);
558 	if (action->rc) {
559 		bdev_ftl_action_finish(action);
560 	}
561 }
562 
563 static void
564 bdev_ftl_finish(void)
565 {
566 	spdk_ftl_fini();
567 }
568 
569 static void
570 bdev_ftl_create_deferred_cb(const struct ftl_bdev_info *info, void *ctx, int status)
571 {
572 	struct ftl_deferred_init *opts = ctx;
573 
574 	if (status) {
575 		SPDK_ERRLOG("Failed to initialize FTL bdev '%s'\n", opts->conf.name);
576 	}
577 
578 	bdev_ftl_defer_free(opts);
579 
580 	spdk_bdev_module_examine_done(&g_ftl_if);
581 }
582 
583 static void
584 bdev_ftl_examine(struct spdk_bdev *bdev)
585 {
586 	struct ftl_deferred_init *opts;
587 	int rc;
588 
589 	LIST_FOREACH(opts, &g_deferred_init, entry) {
590 		/* spdk_bdev_module_examine_done will be called by bdev_ftl_create_deferred_cb */
591 		rc = bdev_ftl_create_bdev(&opts->conf, bdev_ftl_create_deferred_cb, opts);
592 		if (rc == -ENODEV) {
593 			continue;
594 		}
595 
596 		LIST_REMOVE(opts, entry);
597 
598 		if (rc) {
599 			bdev_ftl_create_deferred_cb(NULL, opts, rc);
600 		}
601 		return;
602 	}
603 
604 	spdk_bdev_module_examine_done(&g_ftl_if);
605 }
606 
607 SPDK_LOG_REGISTER_COMPONENT(bdev_ftl)
608 
609 /*
610  * Generic function to execute an action on the FTL bdev
611  */
612 static void
613 bdev_ftl_action_finish(struct bdev_ftl_action *action)
614 {
615 	action->cb_fn(action->cb_arg, action->rc);
616 	if (action->ftl_bdev_desc) {
617 		spdk_bdev_close(action->ftl_bdev_desc);
618 	}
619 	free(action);
620 }
621 
622 static struct bdev_ftl_action *
623 bdev_ftl_action_start(const char *bdev_name, size_t ctx_size, spdk_ftl_fn cb_fn, void *cb_arg)
624 {
625 	struct spdk_bdev *bdev;
626 	struct bdev_ftl_action *action = calloc(1, sizeof(*action) + ctx_size);
627 
628 	if (NULL == action) {
629 		cb_fn(cb_arg, -ENOMEM);
630 		return NULL;
631 	}
632 	action->cb_arg = cb_arg;
633 	action->cb_fn = cb_fn;
634 
635 	action->rc = spdk_bdev_open_ext(bdev_name, false, bdev_ftl_event_cb, NULL, &action->ftl_bdev_desc);
636 	if (action->rc) {
637 		goto error;
638 	}
639 
640 	bdev = spdk_bdev_desc_get_bdev(action->ftl_bdev_desc);
641 	if (bdev->module != &g_ftl_if) {
642 		action->rc = -ENODEV;
643 		goto error;
644 	}
645 
646 	action->ftl_bdev_dev = bdev->ctxt;
647 	assert(action->ftl_bdev_dev);
648 
649 	return action;
650 error:
651 	bdev_ftl_action_finish(action);
652 	return NULL;
653 }
654 
655 static void
656 bdev_ftl_action_finish_cb(void *cb_arg, int status)
657 {
658 	struct bdev_ftl_action *action = cb_arg;
659 
660 	action->rc = status;
661 	bdev_ftl_action_finish(action);
662 }
663