xref: /spdk/module/bdev/rbd/bdev_rbd.c (revision 712a3f69d32632bf6c862f00200f7f437d3f7529)
1 /*-
2  *   BSD LICENSE
3  *
4  *   Copyright (c) Intel Corporation.
5  *   All rights reserved.
6  *
7  *   Redistribution and use in source and binary forms, with or without
8  *   modification, are permitted provided that the following conditions
9  *   are met:
10  *
11  *     * Redistributions of source code must retain the above copyright
12  *       notice, this list of conditions and the following disclaimer.
13  *     * Redistributions in binary form must reproduce the above copyright
14  *       notice, this list of conditions and the following disclaimer in
15  *       the documentation and/or other materials provided with the
16  *       distribution.
17  *     * Neither the name of Intel Corporation nor the names of its
18  *       contributors may be used to endorse or promote products derived
19  *       from this software without specific prior written permission.
20  *
21  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
22  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
23  *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
24  *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
25  *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
26  *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
27  *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
28  *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
29  *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30  *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
31  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32  */
33 
34 #include "spdk/stdinc.h"
35 
36 #include "bdev_rbd.h"
37 
38 #include <rbd/librbd.h>
39 #include <rados/librados.h>
40 #include <sys/eventfd.h>
41 
42 #include "spdk/conf.h"
43 #include "spdk/env.h"
44 #include "spdk/bdev.h"
45 #include "spdk/thread.h"
46 #include "spdk/json.h"
47 #include "spdk/string.h"
48 #include "spdk/util.h"
49 
50 #include "spdk/bdev_module.h"
51 #include "spdk_internal/log.h"
52 
53 #define SPDK_RBD_QUEUE_DEPTH 128
54 
55 static int bdev_rbd_count = 0;
56 
57 #define BDEV_RBD_POLL_US 50
58 
59 struct bdev_rbd {
60 	struct spdk_bdev disk;
61 	char *rbd_name;
62 	char *user_id;
63 	char *pool_name;
64 	char **config;
65 	rbd_image_info_t info;
66 	TAILQ_ENTRY(bdev_rbd) tailq;
67 	struct spdk_poller *reset_timer;
68 	struct spdk_bdev_io *reset_bdev_io;
69 };
70 
71 struct bdev_rbd_io_channel {
72 	rados_ioctx_t io_ctx;
73 	rados_t cluster;
74 	struct pollfd pfd;
75 	rbd_image_t image;
76 	struct bdev_rbd *disk;
77 	struct spdk_poller *poller;
78 };
79 
80 struct bdev_rbd_io {
81 	uint64_t remaining_len;
82 	int num_segments;
83 	bool failed;
84 };
85 
86 static void
87 bdev_rbd_free(struct bdev_rbd *rbd)
88 {
89 	if (!rbd) {
90 		return;
91 	}
92 
93 	free(rbd->disk.name);
94 	free(rbd->rbd_name);
95 	free(rbd->user_id);
96 	free(rbd->pool_name);
97 	spdk_bdev_rbd_free_config(rbd->config);
98 	free(rbd);
99 }
100 
101 void
102 spdk_bdev_rbd_free_config(char **config)
103 {
104 	char **entry;
105 
106 	if (config) {
107 		for (entry = config; *entry; entry++) {
108 			free(*entry);
109 		}
110 		free(config);
111 	}
112 }
113 
114 char **
115 spdk_bdev_rbd_dup_config(const char *const *config)
116 {
117 	size_t count;
118 	char **copy;
119 
120 	if (!config) {
121 		return NULL;
122 	}
123 	for (count = 0; config[count]; count++) {}
124 	copy = calloc(count + 1, sizeof(*copy));
125 	if (!copy) {
126 		return NULL;
127 	}
128 	for (count = 0; config[count]; count++) {
129 		if (!(copy[count] = strdup(config[count]))) {
130 			spdk_bdev_rbd_free_config(copy);
131 			return NULL;
132 		}
133 	}
134 	return copy;
135 }
136 
137 static int
138 bdev_rados_context_init(const char *user_id, const char *rbd_pool_name, const char *const *config,
139 			rados_t *cluster, rados_ioctx_t *io_ctx)
140 {
141 	int ret;
142 
143 	ret = rados_create(cluster, user_id);
144 	if (ret < 0) {
145 		SPDK_ERRLOG("Failed to create rados_t struct\n");
146 		return -1;
147 	}
148 
149 	if (config) {
150 		const char *const *entry = config;
151 		while (*entry) {
152 			ret = rados_conf_set(*cluster, entry[0], entry[1]);
153 			if (ret < 0) {
154 				SPDK_ERRLOG("Failed to set %s = %s\n", entry[0], entry[1]);
155 				rados_shutdown(*cluster);
156 				return -1;
157 			}
158 			entry += 2;
159 		}
160 	} else {
161 		ret = rados_conf_read_file(*cluster, NULL);
162 		if (ret < 0) {
163 			SPDK_ERRLOG("Failed to read conf file\n");
164 			rados_shutdown(*cluster);
165 			return -1;
166 		}
167 	}
168 
169 	ret = rados_connect(*cluster);
170 	if (ret < 0) {
171 		SPDK_ERRLOG("Failed to connect to rbd_pool\n");
172 		rados_shutdown(*cluster);
173 		return -1;
174 	}
175 
176 	ret = rados_ioctx_create(*cluster, rbd_pool_name, io_ctx);
177 
178 	if (ret < 0) {
179 		SPDK_ERRLOG("Failed to create ioctx\n");
180 		rados_shutdown(*cluster);
181 		return -1;
182 	}
183 
184 	return 0;
185 }
186 
187 static int
188 bdev_rbd_init(const char *user_id, const char *rbd_pool_name, const char *const *config,
189 	      const char *rbd_name, rbd_image_info_t *info)
190 {
191 	int ret;
192 	rados_t cluster = NULL;
193 	rados_ioctx_t io_ctx = NULL;
194 	rbd_image_t image = NULL;
195 
196 	ret = bdev_rados_context_init(user_id, rbd_pool_name, config, &cluster, &io_ctx);
197 	if (ret < 0) {
198 		SPDK_ERRLOG("Failed to create rados context for user_id=%s and rbd_pool=%s\n",
199 			    user_id ? user_id : "admin (the default)", rbd_pool_name);
200 		return -1;
201 	}
202 
203 	ret = rbd_open(io_ctx, rbd_name, &image, NULL);
204 	if (ret < 0) {
205 		SPDK_ERRLOG("Failed to open specified rbd device\n");
206 		goto err;
207 	}
208 	ret = rbd_stat(image, info, sizeof(*info));
209 	rbd_close(image);
210 	if (ret < 0) {
211 		SPDK_ERRLOG("Failed to stat specified rbd device\n");
212 		goto err;
213 	}
214 
215 	rados_ioctx_destroy(io_ctx);
216 	return 0;
217 err:
218 	rados_ioctx_destroy(io_ctx);
219 	rados_shutdown(cluster);
220 	return -1;
221 }
222 
223 static void
224 bdev_rbd_exit(rbd_image_t image)
225 {
226 	rbd_flush(image);
227 	rbd_close(image);
228 }
229 
230 static void
231 bdev_rbd_finish_aiocb(rbd_completion_t cb, void *arg)
232 {
233 	/* Doing nothing here */
234 }
235 
236 static int
237 bdev_rbd_start_aio(rbd_image_t image, struct spdk_bdev_io *bdev_io,
238 		   void *buf, uint64_t offset, size_t len)
239 {
240 	int ret;
241 	rbd_completion_t comp;
242 
243 	ret = rbd_aio_create_completion(bdev_io, bdev_rbd_finish_aiocb,
244 					&comp);
245 	if (ret < 0) {
246 		return -1;
247 	}
248 
249 	if (bdev_io->type == SPDK_BDEV_IO_TYPE_READ) {
250 		ret = rbd_aio_read(image, offset, len,
251 				   buf, comp);
252 	} else if (bdev_io->type == SPDK_BDEV_IO_TYPE_WRITE) {
253 		ret = rbd_aio_write(image, offset, len,
254 				    buf, comp);
255 	} else if (bdev_io->type == SPDK_BDEV_IO_TYPE_FLUSH) {
256 		ret = rbd_aio_flush(image, comp);
257 	}
258 
259 	if (ret < 0) {
260 		rbd_aio_release(comp);
261 		return -1;
262 	}
263 
264 	return 0;
265 }
266 
267 static int bdev_rbd_library_init(void);
268 
269 static int
270 bdev_rbd_get_ctx_size(void)
271 {
272 	return sizeof(struct bdev_rbd_io);
273 }
274 
275 static struct spdk_bdev_module rbd_if = {
276 	.name = "rbd",
277 	.module_init = bdev_rbd_library_init,
278 	.get_ctx_size = bdev_rbd_get_ctx_size,
279 
280 };
281 SPDK_BDEV_MODULE_REGISTER(rbd, &rbd_if)
282 
283 static int64_t
284 bdev_rbd_rw(struct bdev_rbd *disk, struct spdk_io_channel *ch,
285 	    struct spdk_bdev_io *bdev_io, struct iovec *iov,
286 	    int iovcnt, size_t len, uint64_t offset)
287 {
288 	struct bdev_rbd_io *rbd_io = (struct bdev_rbd_io *)bdev_io->driver_ctx;
289 	struct bdev_rbd_io_channel *rbdio_ch = spdk_io_channel_get_ctx(ch);
290 	size_t remaining = len;
291 	int i, rc;
292 
293 	rbd_io->remaining_len = 0;
294 	rbd_io->num_segments = 0;
295 	rbd_io->failed = false;
296 
297 	for (i = 0; i < iovcnt && remaining > 0; i++) {
298 		size_t seg_len = spdk_min(remaining, iov[i].iov_len);
299 
300 		rc = bdev_rbd_start_aio(rbdio_ch->image, bdev_io, iov[i].iov_base, offset, seg_len);
301 		if (rc) {
302 			/*
303 			 * This bdev_rbd_start_aio() call failed, but if any previous ones were
304 			 * submitted, we need to wait for them to finish.
305 			 */
306 			if (rbd_io->num_segments == 0) {
307 				/* No previous I/O submitted - return error code immediately. */
308 				return rc;
309 			}
310 
311 			/* Return and wait for outstanding I/O to complete. */
312 			rbd_io->failed = true;
313 			return 0;
314 		}
315 
316 		rbd_io->num_segments++;
317 		rbd_io->remaining_len += seg_len;
318 
319 		offset += seg_len;
320 		remaining -= seg_len;
321 	}
322 
323 	return 0;
324 }
325 
326 static int64_t
327 bdev_rbd_flush(struct bdev_rbd *disk, struct spdk_io_channel *ch,
328 	       struct spdk_bdev_io *bdev_io, uint64_t offset, uint64_t nbytes)
329 {
330 	struct bdev_rbd_io_channel *rbdio_ch = spdk_io_channel_get_ctx(ch);
331 
332 	return bdev_rbd_start_aio(rbdio_ch->image, bdev_io, NULL, offset, nbytes);
333 }
334 
335 static int
336 bdev_rbd_reset_timer(void *arg)
337 {
338 	struct bdev_rbd *disk = arg;
339 
340 	/*
341 	 * TODO: This should check if any I/O is still in flight before completing the reset.
342 	 * For now, just complete after the timer expires.
343 	 */
344 	spdk_bdev_io_complete(disk->reset_bdev_io, SPDK_BDEV_IO_STATUS_SUCCESS);
345 	spdk_poller_unregister(&disk->reset_timer);
346 	disk->reset_bdev_io = NULL;
347 
348 	return -1;
349 }
350 
351 static int
352 bdev_rbd_reset(struct bdev_rbd *disk, struct spdk_bdev_io *bdev_io)
353 {
354 	/*
355 	 * HACK: Since librbd doesn't provide any way to cancel outstanding aio, just kick off a
356 	 * timer to wait for in-flight I/O to complete.
357 	 */
358 	assert(disk->reset_bdev_io == NULL);
359 	disk->reset_bdev_io = bdev_io;
360 	disk->reset_timer = spdk_poller_register(bdev_rbd_reset_timer, disk, 1 * 1000 * 1000);
361 
362 	return 0;
363 }
364 
365 static int
366 bdev_rbd_destruct(void *ctx)
367 {
368 	struct bdev_rbd *rbd = ctx;
369 
370 	spdk_io_device_unregister(rbd, NULL);
371 
372 	bdev_rbd_free(rbd);
373 	return 0;
374 }
375 
376 static void
377 bdev_rbd_get_buf_cb(struct spdk_io_channel *ch, struct spdk_bdev_io *bdev_io,
378 		    bool success)
379 {
380 	int ret;
381 
382 	if (!success) {
383 		spdk_bdev_io_complete(bdev_io, SPDK_BDEV_IO_STATUS_FAILED);
384 		return;
385 	}
386 
387 	ret = bdev_rbd_rw(bdev_io->bdev->ctxt,
388 			  ch,
389 			  bdev_io,
390 			  bdev_io->u.bdev.iovs,
391 			  bdev_io->u.bdev.iovcnt,
392 			  bdev_io->u.bdev.num_blocks * bdev_io->bdev->blocklen,
393 			  bdev_io->u.bdev.offset_blocks * bdev_io->bdev->blocklen);
394 
395 	if (ret != 0) {
396 		spdk_bdev_io_complete(bdev_io, SPDK_BDEV_IO_STATUS_FAILED);
397 	}
398 }
399 
400 static int _bdev_rbd_submit_request(struct spdk_io_channel *ch, struct spdk_bdev_io *bdev_io)
401 {
402 	switch (bdev_io->type) {
403 	case SPDK_BDEV_IO_TYPE_READ:
404 		spdk_bdev_io_get_buf(bdev_io, bdev_rbd_get_buf_cb,
405 				     bdev_io->u.bdev.num_blocks * bdev_io->bdev->blocklen);
406 		return 0;
407 
408 	case SPDK_BDEV_IO_TYPE_WRITE:
409 		return bdev_rbd_rw((struct bdev_rbd *)bdev_io->bdev->ctxt,
410 				   ch,
411 				   bdev_io,
412 				   bdev_io->u.bdev.iovs,
413 				   bdev_io->u.bdev.iovcnt,
414 				   bdev_io->u.bdev.num_blocks * bdev_io->bdev->blocklen,
415 				   bdev_io->u.bdev.offset_blocks * bdev_io->bdev->blocklen);
416 
417 	case SPDK_BDEV_IO_TYPE_FLUSH:
418 		return bdev_rbd_flush((struct bdev_rbd *)bdev_io->bdev->ctxt,
419 				      ch,
420 				      bdev_io,
421 				      bdev_io->u.bdev.offset_blocks * bdev_io->bdev->blocklen,
422 				      bdev_io->u.bdev.num_blocks * bdev_io->bdev->blocklen);
423 
424 	case SPDK_BDEV_IO_TYPE_RESET:
425 		return bdev_rbd_reset((struct bdev_rbd *)bdev_io->bdev->ctxt,
426 				      bdev_io);
427 
428 	default:
429 		return -1;
430 	}
431 	return 0;
432 }
433 
434 static void bdev_rbd_submit_request(struct spdk_io_channel *ch, struct spdk_bdev_io *bdev_io)
435 {
436 	if (_bdev_rbd_submit_request(ch, bdev_io) < 0) {
437 		spdk_bdev_io_complete(bdev_io, SPDK_BDEV_IO_STATUS_FAILED);
438 	}
439 }
440 
441 static bool
442 bdev_rbd_io_type_supported(void *ctx, enum spdk_bdev_io_type io_type)
443 {
444 	switch (io_type) {
445 	case SPDK_BDEV_IO_TYPE_READ:
446 	case SPDK_BDEV_IO_TYPE_WRITE:
447 	case SPDK_BDEV_IO_TYPE_FLUSH:
448 	case SPDK_BDEV_IO_TYPE_RESET:
449 		return true;
450 
451 	default:
452 		return false;
453 	}
454 }
455 
456 static int
457 bdev_rbd_io_poll(void *arg)
458 {
459 	struct bdev_rbd_io_channel *ch = arg;
460 	int i, io_status, rc;
461 	rbd_completion_t comps[SPDK_RBD_QUEUE_DEPTH];
462 	struct spdk_bdev_io *bdev_io;
463 	struct bdev_rbd_io *rbd_io;
464 
465 	rc = poll(&ch->pfd, 1, 0);
466 
467 	/* check the return value of poll since we have only one fd for each channel */
468 	if (rc != 1) {
469 		return 0;
470 	}
471 
472 	rc = rbd_poll_io_events(ch->image, comps, SPDK_RBD_QUEUE_DEPTH);
473 	for (i = 0; i < rc; i++) {
474 		bdev_io = rbd_aio_get_arg(comps[i]);
475 		rbd_io = (struct bdev_rbd_io *)bdev_io->driver_ctx;
476 		io_status = rbd_aio_get_return_value(comps[i]);
477 
478 		assert(rbd_io->num_segments > 0);
479 		rbd_io->num_segments--;
480 
481 		if (bdev_io->type == SPDK_BDEV_IO_TYPE_READ) {
482 			if (io_status > 0) {
483 				/* For reads, io_status is the length */
484 				rbd_io->remaining_len -= io_status;
485 			}
486 
487 			if (rbd_io->num_segments == 0 && rbd_io->remaining_len != 0) {
488 				rbd_io->failed = true;
489 			}
490 		} else {
491 			/* For others, 0 means success */
492 			if (io_status != 0) {
493 				rbd_io->failed = true;
494 			}
495 		}
496 
497 		rbd_aio_release(comps[i]);
498 
499 		if (rbd_io->num_segments == 0) {
500 			spdk_bdev_io_complete(bdev_io,
501 					      rbd_io->failed ? SPDK_BDEV_IO_STATUS_FAILED : SPDK_BDEV_IO_STATUS_SUCCESS);
502 		}
503 	}
504 
505 	return rc;
506 }
507 
508 static void
509 bdev_rbd_free_channel(struct bdev_rbd_io_channel *ch)
510 {
511 	if (!ch) {
512 		return;
513 	}
514 
515 	if (ch->image) {
516 		bdev_rbd_exit(ch->image);
517 	}
518 
519 	if (ch->io_ctx) {
520 		rados_ioctx_destroy(ch->io_ctx);
521 	}
522 
523 	if (ch->cluster) {
524 		rados_shutdown(ch->cluster);
525 	}
526 
527 	if (ch->pfd.fd >= 0) {
528 		close(ch->pfd.fd);
529 	}
530 }
531 
532 static void *
533 bdev_rbd_handle(void *arg)
534 {
535 	struct bdev_rbd_io_channel *ch = arg;
536 	void *ret = arg;
537 
538 	if (rbd_open(ch->io_ctx, ch->disk->rbd_name, &ch->image, NULL) < 0) {
539 		SPDK_ERRLOG("Failed to open specified rbd device\n");
540 		ret = NULL;
541 	}
542 
543 	return ret;
544 }
545 
546 static int
547 bdev_rbd_create_cb(void *io_device, void *ctx_buf)
548 {
549 	struct bdev_rbd_io_channel *ch = ctx_buf;
550 	int ret;
551 
552 	ch->disk = io_device;
553 	ch->image = NULL;
554 	ch->io_ctx = NULL;
555 	ch->pfd.fd = -1;
556 
557 	ret = bdev_rados_context_init(ch->disk->user_id, ch->disk->pool_name,
558 				      (const char *const *)ch->disk->config,
559 				      &ch->cluster, &ch->io_ctx);
560 	if (ret < 0) {
561 		SPDK_ERRLOG("Failed to create rados context for user_id %s and rbd_pool=%s\n",
562 			    ch->disk->user_id ? ch->disk->user_id : "admin (the default)", ch->disk->pool_name);
563 		goto err;
564 	}
565 
566 	if (spdk_call_unaffinitized(bdev_rbd_handle, ch) == NULL) {
567 		goto err;
568 	}
569 
570 	ch->pfd.fd = eventfd(0, EFD_NONBLOCK);
571 	if (ch->pfd.fd < 0) {
572 		SPDK_ERRLOG("Failed to get eventfd\n");
573 		goto err;
574 	}
575 
576 	ch->pfd.events = POLLIN;
577 	ret = rbd_set_image_notification(ch->image, ch->pfd.fd, EVENT_TYPE_EVENTFD);
578 	if (ret < 0) {
579 		SPDK_ERRLOG("Failed to set rbd image notification\n");
580 		goto err;
581 	}
582 
583 	ch->poller = spdk_poller_register(bdev_rbd_io_poll, ch, BDEV_RBD_POLL_US);
584 
585 	return 0;
586 
587 err:
588 	bdev_rbd_free_channel(ch);
589 	return -1;
590 }
591 
592 static void
593 bdev_rbd_destroy_cb(void *io_device, void *ctx_buf)
594 {
595 	struct bdev_rbd_io_channel *io_channel = ctx_buf;
596 
597 	bdev_rbd_free_channel(io_channel);
598 
599 	spdk_poller_unregister(&io_channel->poller);
600 }
601 
602 static struct spdk_io_channel *
603 bdev_rbd_get_io_channel(void *ctx)
604 {
605 	struct bdev_rbd *rbd_bdev = ctx;
606 
607 	return spdk_get_io_channel(rbd_bdev);
608 }
609 
610 static int
611 bdev_rbd_dump_info_json(void *ctx, struct spdk_json_write_ctx *w)
612 {
613 	struct bdev_rbd *rbd_bdev = ctx;
614 
615 	spdk_json_write_named_object_begin(w, "rbd");
616 
617 	spdk_json_write_named_string(w, "pool_name", rbd_bdev->pool_name);
618 
619 	spdk_json_write_named_string(w, "rbd_name", rbd_bdev->rbd_name);
620 
621 	if (rbd_bdev->user_id) {
622 		spdk_json_write_named_string(w, "user_id", rbd_bdev->user_id);
623 	}
624 
625 	if (rbd_bdev->config) {
626 		char **entry = rbd_bdev->config;
627 
628 		spdk_json_write_named_object_begin(w, "config");
629 		while (*entry) {
630 			spdk_json_write_named_string(w, entry[0], entry[1]);
631 			entry += 2;
632 		}
633 		spdk_json_write_object_end(w);
634 	}
635 
636 	spdk_json_write_object_end(w);
637 
638 	return 0;
639 }
640 
641 static void
642 bdev_rbd_write_config_json(struct spdk_bdev *bdev, struct spdk_json_write_ctx *w)
643 {
644 	struct bdev_rbd *rbd = bdev->ctxt;
645 
646 	spdk_json_write_object_begin(w);
647 
648 	spdk_json_write_named_string(w, "method", "bdev_rbd_create");
649 
650 	spdk_json_write_named_object_begin(w, "params");
651 	spdk_json_write_named_string(w, "name", bdev->name);
652 	spdk_json_write_named_string(w, "pool_name", rbd->pool_name);
653 	spdk_json_write_named_string(w, "rbd_name", rbd->rbd_name);
654 	spdk_json_write_named_uint32(w, "block_size", bdev->blocklen);
655 	if (rbd->user_id) {
656 		spdk_json_write_named_string(w, "user_id", rbd->user_id);
657 	}
658 
659 	if (rbd->config) {
660 		char **entry = rbd->config;
661 
662 		spdk_json_write_named_object_begin(w, "config");
663 		while (*entry) {
664 			spdk_json_write_named_string(w, entry[0], entry[1]);
665 			entry += 2;
666 		}
667 		spdk_json_write_object_end(w);
668 	}
669 
670 	spdk_json_write_object_end(w);
671 
672 	spdk_json_write_object_end(w);
673 }
674 
675 static const struct spdk_bdev_fn_table rbd_fn_table = {
676 	.destruct		= bdev_rbd_destruct,
677 	.submit_request		= bdev_rbd_submit_request,
678 	.io_type_supported	= bdev_rbd_io_type_supported,
679 	.get_io_channel		= bdev_rbd_get_io_channel,
680 	.dump_info_json		= bdev_rbd_dump_info_json,
681 	.write_config_json	= bdev_rbd_write_config_json,
682 };
683 
684 int
685 spdk_bdev_rbd_create(struct spdk_bdev **bdev, const char *name, const char *user_id,
686 		     const char *pool_name,
687 		     const char *const *config,
688 		     const char *rbd_name,
689 		     uint32_t block_size)
690 {
691 	struct bdev_rbd *rbd;
692 	int ret;
693 
694 	if ((pool_name == NULL) || (rbd_name == NULL)) {
695 		return -EINVAL;
696 	}
697 
698 	rbd = calloc(1, sizeof(struct bdev_rbd));
699 	if (rbd == NULL) {
700 		SPDK_ERRLOG("Failed to allocate bdev_rbd struct\n");
701 		return -ENOMEM;
702 	}
703 
704 	rbd->rbd_name = strdup(rbd_name);
705 	if (!rbd->rbd_name) {
706 		bdev_rbd_free(rbd);
707 		return -ENOMEM;
708 	}
709 
710 	if (user_id) {
711 		rbd->user_id = strdup(user_id);
712 		if (!rbd->user_id) {
713 			bdev_rbd_free(rbd);
714 			return -ENOMEM;
715 		}
716 	}
717 
718 	rbd->pool_name = strdup(pool_name);
719 	if (!rbd->pool_name) {
720 		bdev_rbd_free(rbd);
721 		return -ENOMEM;
722 	}
723 
724 	if (config && !(rbd->config = spdk_bdev_rbd_dup_config(config))) {
725 		bdev_rbd_free(rbd);
726 		return -ENOMEM;
727 	}
728 
729 	ret = bdev_rbd_init(rbd->user_id, rbd->pool_name,
730 			    (const char *const *)rbd->config,
731 			    rbd_name, &rbd->info);
732 	if (ret < 0) {
733 		bdev_rbd_free(rbd);
734 		SPDK_ERRLOG("Failed to init rbd device\n");
735 		return ret;
736 	}
737 
738 	if (name) {
739 		rbd->disk.name = strdup(name);
740 	} else {
741 		rbd->disk.name = spdk_sprintf_alloc("Ceph%d", bdev_rbd_count);
742 	}
743 	if (!rbd->disk.name) {
744 		bdev_rbd_free(rbd);
745 		return -ENOMEM;
746 	}
747 	rbd->disk.product_name = "Ceph Rbd Disk";
748 	bdev_rbd_count++;
749 
750 	rbd->disk.write_cache = 0;
751 	rbd->disk.blocklen = block_size;
752 	rbd->disk.blockcnt = rbd->info.size / rbd->disk.blocklen;
753 	rbd->disk.ctxt = rbd;
754 	rbd->disk.fn_table = &rbd_fn_table;
755 	rbd->disk.module = &rbd_if;
756 
757 	SPDK_NOTICELOG("Add %s rbd disk to lun\n", rbd->disk.name);
758 
759 	spdk_io_device_register(rbd, bdev_rbd_create_cb,
760 				bdev_rbd_destroy_cb,
761 				sizeof(struct bdev_rbd_io_channel),
762 				rbd_name);
763 	ret = spdk_bdev_register(&rbd->disk);
764 	if (ret) {
765 		spdk_io_device_unregister(rbd, NULL);
766 		bdev_rbd_free(rbd);
767 		return ret;
768 	}
769 
770 	*bdev = &(rbd->disk);
771 
772 	return ret;
773 }
774 
775 void
776 spdk_bdev_rbd_delete(struct spdk_bdev *bdev, spdk_delete_rbd_complete cb_fn, void *cb_arg)
777 {
778 	if (!bdev || bdev->module != &rbd_if) {
779 		cb_fn(cb_arg, -ENODEV);
780 		return;
781 	}
782 
783 	spdk_bdev_unregister(bdev, cb_fn, cb_arg);
784 }
785 
786 static int
787 bdev_rbd_library_init(void)
788 {
789 	int i, rc = 0;
790 	const char *val;
791 	const char *pool_name;
792 	const char *rbd_name;
793 	struct spdk_bdev *bdev;
794 	uint32_t block_size;
795 	long int tmp;
796 
797 	struct spdk_conf_section *sp = spdk_conf_find_section(NULL, "Ceph");
798 
799 	if (sp == NULL) {
800 		/*
801 		 * Ceph section not found.  Do not initialize any rbd LUNS.
802 		 */
803 		goto end;
804 	}
805 
806 	/* Init rbd block devices */
807 	for (i = 0; ; i++) {
808 		val = spdk_conf_section_get_nval(sp, "Ceph", i);
809 		if (val == NULL) {
810 			break;
811 		}
812 
813 		/* get the Rbd_pool name */
814 		pool_name = spdk_conf_section_get_nmval(sp, "Ceph", i, 0);
815 		if (pool_name == NULL) {
816 			SPDK_ERRLOG("Ceph%d: rbd pool name needs to be provided\n", i);
817 			rc = -1;
818 			goto end;
819 		}
820 
821 		rbd_name = spdk_conf_section_get_nmval(sp, "Ceph", i, 1);
822 		if (rbd_name == NULL) {
823 			SPDK_ERRLOG("Ceph%d: format error\n", i);
824 			rc = -1;
825 			goto end;
826 		}
827 
828 		val = spdk_conf_section_get_nmval(sp, "Ceph", i, 2);
829 
830 		if (val == NULL) {
831 			block_size = 512; /* default value */
832 		} else {
833 			tmp = spdk_strtol(val, 10);
834 			if (tmp <= 0) {
835 				SPDK_ERRLOG("Invalid block size\n");
836 				rc = -1;
837 				goto end;
838 			} else if (tmp & 0x1ff) {
839 				SPDK_ERRLOG("current block_size = %ld, it should be multiple of 512\n",
840 					    tmp);
841 				rc = -1;
842 				goto end;
843 			}
844 			block_size = (uint32_t)tmp;
845 		}
846 
847 		/* TODO(?): user_id and rbd config values */
848 		rc = spdk_bdev_rbd_create(&bdev, NULL, NULL, pool_name, NULL, rbd_name, block_size);
849 		if (rc) {
850 			goto end;
851 		}
852 	}
853 
854 end:
855 	return rc;
856 }
857 
858 SPDK_LOG_REGISTER_COMPONENT("bdev_rbd", SPDK_LOG_BDEV_RBD)
859