xref: /spdk/module/bdev/raid/bdev_raid.c (revision f8abbede89d30584d2a4f8427b13896f8591b873)
1 /*   SPDX-License-Identifier: BSD-3-Clause
2  *   Copyright (C) 2018 Intel Corporation.
3  *   All rights reserved.
4  *   Copyright (c) 2022, NVIDIA CORPORATION & AFFILIATES. All rights reserved.
5  */
6 
7 #include "bdev_raid.h"
8 #include "spdk/env.h"
9 #include "spdk/thread.h"
10 #include "spdk/log.h"
11 #include "spdk/string.h"
12 #include "spdk/util.h"
13 #include "spdk/json.h"
14 
15 static bool g_shutdown_started = false;
16 
17 /* List of all raid bdevs */
18 struct raid_all_tailq g_raid_bdev_list = TAILQ_HEAD_INITIALIZER(g_raid_bdev_list);
19 
20 static TAILQ_HEAD(, raid_bdev_module) g_raid_modules = TAILQ_HEAD_INITIALIZER(g_raid_modules);
21 
22 static struct raid_bdev_module *
23 raid_bdev_module_find(enum raid_level level)
24 {
25 	struct raid_bdev_module *raid_module;
26 
27 	TAILQ_FOREACH(raid_module, &g_raid_modules, link) {
28 		if (raid_module->level == level) {
29 			return raid_module;
30 		}
31 	}
32 
33 	return NULL;
34 }
35 
36 void
37 raid_bdev_module_list_add(struct raid_bdev_module *raid_module)
38 {
39 	if (raid_bdev_module_find(raid_module->level) != NULL) {
40 		SPDK_ERRLOG("module for raid level '%s' already registered.\n",
41 			    raid_bdev_level_to_str(raid_module->level));
42 		assert(false);
43 	} else {
44 		TAILQ_INSERT_TAIL(&g_raid_modules, raid_module, link);
45 	}
46 }
47 
48 /* Function declarations */
49 static void	raid_bdev_examine(struct spdk_bdev *bdev);
50 static int	raid_bdev_init(void);
51 static void	raid_bdev_deconfigure(struct raid_bdev *raid_bdev,
52 				      raid_bdev_destruct_cb cb_fn, void *cb_arg);
53 
54 /*
55  * brief:
56  * raid_bdev_create_cb function is a cb function for raid bdev which creates the
57  * hierarchy from raid bdev to base bdev io channels. It will be called per core
58  * params:
59  * io_device - pointer to raid bdev io device represented by raid_bdev
60  * ctx_buf - pointer to context buffer for raid bdev io channel
61  * returns:
62  * 0 - success
63  * non zero - failure
64  */
65 static int
66 raid_bdev_create_cb(void *io_device, void *ctx_buf)
67 {
68 	struct raid_bdev            *raid_bdev = io_device;
69 	struct raid_bdev_io_channel *raid_ch = ctx_buf;
70 	uint8_t i;
71 	int ret = 0;
72 
73 	SPDK_DEBUGLOG(bdev_raid, "raid_bdev_create_cb, %p\n", raid_ch);
74 
75 	assert(raid_bdev != NULL);
76 	assert(raid_bdev->state == RAID_BDEV_STATE_ONLINE);
77 
78 	raid_ch->num_channels = raid_bdev->num_base_bdevs;
79 
80 	raid_ch->base_channel = calloc(raid_ch->num_channels,
81 				       sizeof(struct spdk_io_channel *));
82 	if (!raid_ch->base_channel) {
83 		SPDK_ERRLOG("Unable to allocate base bdevs io channel\n");
84 		return -ENOMEM;
85 	}
86 
87 	spdk_spin_lock(&raid_bdev->base_bdev_lock);
88 	for (i = 0; i < raid_ch->num_channels; i++) {
89 		/*
90 		 * Get the spdk_io_channel for all the base bdevs. This is used during
91 		 * split logic to send the respective child bdev ios to respective base
92 		 * bdev io channel.
93 		 */
94 		if (raid_bdev->base_bdev_info[i].desc == NULL) {
95 			continue;
96 		}
97 		raid_ch->base_channel[i] = spdk_bdev_get_io_channel(
98 						   raid_bdev->base_bdev_info[i].desc);
99 		if (!raid_ch->base_channel[i]) {
100 			SPDK_ERRLOG("Unable to create io channel for base bdev\n");
101 			ret = -ENOMEM;
102 			break;
103 		}
104 	}
105 	spdk_spin_unlock(&raid_bdev->base_bdev_lock);
106 
107 	if (!ret && raid_bdev->module->get_io_channel) {
108 		raid_ch->module_channel = raid_bdev->module->get_io_channel(raid_bdev);
109 		if (!raid_ch->module_channel) {
110 			SPDK_ERRLOG("Unable to create io channel for raid module\n");
111 			ret = -ENOMEM;
112 		}
113 	}
114 
115 	if (ret) {
116 		for (i = 0; i < raid_ch->num_channels; i++) {
117 			if (raid_ch->base_channel[i] != NULL) {
118 				spdk_put_io_channel(raid_ch->base_channel[i]);
119 			}
120 		}
121 		free(raid_ch->base_channel);
122 		raid_ch->base_channel = NULL;
123 	}
124 	return ret;
125 }
126 
127 /*
128  * brief:
129  * raid_bdev_destroy_cb function is a cb function for raid bdev which deletes the
130  * hierarchy from raid bdev to base bdev io channels. It will be called per core
131  * params:
132  * io_device - pointer to raid bdev io device represented by raid_bdev
133  * ctx_buf - pointer to context buffer for raid bdev io channel
134  * returns:
135  * none
136  */
137 static void
138 raid_bdev_destroy_cb(void *io_device, void *ctx_buf)
139 {
140 	struct raid_bdev_io_channel *raid_ch = ctx_buf;
141 	uint8_t i;
142 
143 	SPDK_DEBUGLOG(bdev_raid, "raid_bdev_destroy_cb\n");
144 
145 	assert(raid_ch != NULL);
146 	assert(raid_ch->base_channel);
147 
148 	if (raid_ch->module_channel) {
149 		spdk_put_io_channel(raid_ch->module_channel);
150 	}
151 
152 	for (i = 0; i < raid_ch->num_channels; i++) {
153 		/* Free base bdev channels */
154 		if (raid_ch->base_channel[i] != NULL) {
155 			spdk_put_io_channel(raid_ch->base_channel[i]);
156 		}
157 	}
158 	free(raid_ch->base_channel);
159 	raid_ch->base_channel = NULL;
160 }
161 
162 /*
163  * brief:
164  * raid_bdev_cleanup is used to cleanup raid_bdev related data
165  * structures.
166  * params:
167  * raid_bdev - pointer to raid_bdev
168  * returns:
169  * none
170  */
171 static void
172 raid_bdev_cleanup(struct raid_bdev *raid_bdev)
173 {
174 	struct raid_base_bdev_info *base_info;
175 
176 	SPDK_DEBUGLOG(bdev_raid, "raid_bdev_cleanup, %p name %s, state %s\n",
177 		      raid_bdev, raid_bdev->bdev.name, raid_bdev_state_to_str(raid_bdev->state));
178 	assert(raid_bdev->state != RAID_BDEV_STATE_ONLINE);
179 	assert(spdk_get_thread() == spdk_thread_get_app_thread());
180 
181 	RAID_FOR_EACH_BASE_BDEV(raid_bdev, base_info) {
182 		assert(base_info->desc == NULL);
183 		free(base_info->name);
184 	}
185 
186 	TAILQ_REMOVE(&g_raid_bdev_list, raid_bdev, global_link);
187 }
188 
189 static void
190 raid_bdev_free(struct raid_bdev *raid_bdev)
191 {
192 	spdk_spin_destroy(&raid_bdev->base_bdev_lock);
193 	free(raid_bdev->base_bdev_info);
194 	free(raid_bdev->bdev.name);
195 	free(raid_bdev);
196 }
197 
198 static void
199 raid_bdev_cleanup_and_free(struct raid_bdev *raid_bdev)
200 {
201 	raid_bdev_cleanup(raid_bdev);
202 	raid_bdev_free(raid_bdev);
203 }
204 
205 /*
206  * brief:
207  * free resource of base bdev for raid bdev
208  * params:
209  * base_info - raid base bdev info
210  * returns:
211  * 0 - success
212  * non zero - failure
213  */
214 static void
215 raid_bdev_free_base_bdev_resource(struct raid_base_bdev_info *base_info)
216 {
217 	struct raid_bdev *raid_bdev = base_info->raid_bdev;
218 
219 	assert(spdk_get_thread() == spdk_thread_get_app_thread());
220 
221 	free(base_info->name);
222 	base_info->name = NULL;
223 
224 	if (base_info->desc == NULL) {
225 		return;
226 	}
227 
228 	spdk_bdev_module_release_bdev(spdk_bdev_desc_get_bdev(base_info->desc));
229 	spdk_bdev_close(base_info->desc);
230 	base_info->desc = NULL;
231 
232 	assert(raid_bdev->num_base_bdevs_discovered);
233 	raid_bdev->num_base_bdevs_discovered--;
234 }
235 
236 static void
237 raid_bdev_io_device_unregister_cb(void *io_device)
238 {
239 	struct raid_bdev *raid_bdev = io_device;
240 
241 	if (raid_bdev->num_base_bdevs_discovered == 0) {
242 		/* Free raid_bdev when there are no base bdevs left */
243 		SPDK_DEBUGLOG(bdev_raid, "raid bdev base bdevs is 0, going to free all in destruct\n");
244 		raid_bdev_cleanup(raid_bdev);
245 		spdk_bdev_destruct_done(&raid_bdev->bdev, 0);
246 		raid_bdev_free(raid_bdev);
247 	} else {
248 		spdk_bdev_destruct_done(&raid_bdev->bdev, 0);
249 	}
250 }
251 
252 void
253 raid_bdev_module_stop_done(struct raid_bdev *raid_bdev)
254 {
255 	if (raid_bdev->state != RAID_BDEV_STATE_CONFIGURING) {
256 		spdk_io_device_unregister(raid_bdev, raid_bdev_io_device_unregister_cb);
257 	}
258 }
259 
260 static void
261 _raid_bdev_destruct(void *ctxt)
262 {
263 	struct raid_bdev *raid_bdev = ctxt;
264 	struct raid_base_bdev_info *base_info;
265 
266 	SPDK_DEBUGLOG(bdev_raid, "raid_bdev_destruct\n");
267 
268 	RAID_FOR_EACH_BASE_BDEV(raid_bdev, base_info) {
269 		/*
270 		 * Close all base bdev descriptors for which call has come from below
271 		 * layers.  Also close the descriptors if we have started shutdown.
272 		 */
273 		if (g_shutdown_started || base_info->remove_scheduled == true) {
274 			raid_bdev_free_base_bdev_resource(base_info);
275 		}
276 	}
277 
278 	if (g_shutdown_started) {
279 		raid_bdev->state = RAID_BDEV_STATE_OFFLINE;
280 	}
281 
282 	if (raid_bdev->module->stop != NULL) {
283 		if (raid_bdev->module->stop(raid_bdev) == false) {
284 			return;
285 		}
286 	}
287 
288 	raid_bdev_module_stop_done(raid_bdev);
289 }
290 
291 static int
292 raid_bdev_destruct(void *ctx)
293 {
294 	spdk_thread_exec_msg(spdk_thread_get_app_thread(), _raid_bdev_destruct, ctx);
295 
296 	return 1;
297 }
298 
299 void
300 raid_bdev_io_complete(struct raid_bdev_io *raid_io, enum spdk_bdev_io_status status)
301 {
302 	struct spdk_bdev_io *bdev_io = spdk_bdev_io_from_ctx(raid_io);
303 
304 	spdk_bdev_io_complete(bdev_io, status);
305 }
306 
307 /*
308  * brief:
309  * raid_bdev_io_complete_part - signal the completion of a part of the expected
310  * base bdev IOs and complete the raid_io if this is the final expected IO.
311  * The caller should first set raid_io->base_bdev_io_remaining. This function
312  * will decrement this counter by the value of the 'completed' parameter and
313  * complete the raid_io if the counter reaches 0. The caller is free to
314  * interpret the 'base_bdev_io_remaining' and 'completed' values as needed,
315  * it can represent e.g. blocks or IOs.
316  * params:
317  * raid_io - pointer to raid_bdev_io
318  * completed - the part of the raid_io that has been completed
319  * status - status of the base IO
320  * returns:
321  * true - if the raid_io is completed
322  * false - otherwise
323  */
324 bool
325 raid_bdev_io_complete_part(struct raid_bdev_io *raid_io, uint64_t completed,
326 			   enum spdk_bdev_io_status status)
327 {
328 	assert(raid_io->base_bdev_io_remaining >= completed);
329 	raid_io->base_bdev_io_remaining -= completed;
330 
331 	if (status != SPDK_BDEV_IO_STATUS_SUCCESS) {
332 		raid_io->base_bdev_io_status = status;
333 	}
334 
335 	if (raid_io->base_bdev_io_remaining == 0) {
336 		raid_bdev_io_complete(raid_io, raid_io->base_bdev_io_status);
337 		return true;
338 	} else {
339 		return false;
340 	}
341 }
342 
343 /*
344  * brief:
345  * raid_bdev_queue_io_wait function processes the IO which failed to submit.
346  * It will try to queue the IOs after storing the context to bdev wait queue logic.
347  * params:
348  * raid_io - pointer to raid_bdev_io
349  * bdev - the block device that the IO is submitted to
350  * ch - io channel
351  * cb_fn - callback when the spdk_bdev_io for bdev becomes available
352  * returns:
353  * none
354  */
355 void
356 raid_bdev_queue_io_wait(struct raid_bdev_io *raid_io, struct spdk_bdev *bdev,
357 			struct spdk_io_channel *ch, spdk_bdev_io_wait_cb cb_fn)
358 {
359 	raid_io->waitq_entry.bdev = bdev;
360 	raid_io->waitq_entry.cb_fn = cb_fn;
361 	raid_io->waitq_entry.cb_arg = raid_io;
362 	spdk_bdev_queue_io_wait(bdev, ch, &raid_io->waitq_entry);
363 }
364 
365 static void
366 raid_base_bdev_reset_complete(struct spdk_bdev_io *bdev_io, bool success, void *cb_arg)
367 {
368 	struct raid_bdev_io *raid_io = cb_arg;
369 
370 	spdk_bdev_free_io(bdev_io);
371 
372 	raid_bdev_io_complete_part(raid_io, 1, success ?
373 				   SPDK_BDEV_IO_STATUS_SUCCESS :
374 				   SPDK_BDEV_IO_STATUS_FAILED);
375 }
376 
377 static void raid_bdev_submit_reset_request(struct raid_bdev_io *raid_io);
378 
379 static void
380 _raid_bdev_submit_reset_request(void *_raid_io)
381 {
382 	struct raid_bdev_io *raid_io = _raid_io;
383 
384 	raid_bdev_submit_reset_request(raid_io);
385 }
386 
387 /*
388  * brief:
389  * raid_bdev_submit_reset_request function submits reset requests
390  * to member disks; it will submit as many as possible unless a reset fails with -ENOMEM, in
391  * which case it will queue it for later submission
392  * params:
393  * raid_io
394  * returns:
395  * none
396  */
397 static void
398 raid_bdev_submit_reset_request(struct raid_bdev_io *raid_io)
399 {
400 	struct raid_bdev		*raid_bdev;
401 	int				ret;
402 	uint8_t				i;
403 	struct raid_base_bdev_info	*base_info;
404 	struct spdk_io_channel		*base_ch;
405 
406 	raid_bdev = raid_io->raid_bdev;
407 
408 	if (raid_io->base_bdev_io_remaining == 0) {
409 		raid_io->base_bdev_io_remaining = raid_bdev->num_base_bdevs;
410 	}
411 
412 	for (i = raid_io->base_bdev_io_submitted; i < raid_bdev->num_base_bdevs; i++) {
413 		base_info = &raid_bdev->base_bdev_info[i];
414 		base_ch = raid_io->raid_ch->base_channel[i];
415 		if (base_ch == NULL) {
416 			raid_io->base_bdev_io_submitted++;
417 			raid_bdev_io_complete_part(raid_io, 1, SPDK_BDEV_IO_STATUS_SUCCESS);
418 			continue;
419 		}
420 		ret = spdk_bdev_reset(base_info->desc, base_ch,
421 				      raid_base_bdev_reset_complete, raid_io);
422 		if (ret == 0) {
423 			raid_io->base_bdev_io_submitted++;
424 		} else if (ret == -ENOMEM) {
425 			raid_bdev_queue_io_wait(raid_io, spdk_bdev_desc_get_bdev(base_info->desc),
426 						base_ch, _raid_bdev_submit_reset_request);
427 			return;
428 		} else {
429 			SPDK_ERRLOG("bdev io submit error not due to ENOMEM, it should not happen\n");
430 			assert(false);
431 			raid_bdev_io_complete(raid_io, SPDK_BDEV_IO_STATUS_FAILED);
432 			return;
433 		}
434 	}
435 }
436 
437 /*
438  * brief:
439  * Callback function to spdk_bdev_io_get_buf.
440  * params:
441  * ch - pointer to raid bdev io channel
442  * bdev_io - pointer to parent bdev_io on raid bdev device
443  * success - True if buffer is allocated or false otherwise.
444  * returns:
445  * none
446  */
447 static void
448 raid_bdev_get_buf_cb(struct spdk_io_channel *ch, struct spdk_bdev_io *bdev_io,
449 		     bool success)
450 {
451 	struct raid_bdev_io *raid_io = (struct raid_bdev_io *)bdev_io->driver_ctx;
452 
453 	if (!success) {
454 		raid_bdev_io_complete(raid_io, SPDK_BDEV_IO_STATUS_FAILED);
455 		return;
456 	}
457 
458 	raid_io->raid_bdev->module->submit_rw_request(raid_io);
459 }
460 
461 /*
462  * brief:
463  * raid_bdev_submit_request function is the submit_request function pointer of
464  * raid bdev function table. This is used to submit the io on raid_bdev to below
465  * layers.
466  * params:
467  * ch - pointer to raid bdev io channel
468  * bdev_io - pointer to parent bdev_io on raid bdev device
469  * returns:
470  * none
471  */
472 static void
473 raid_bdev_submit_request(struct spdk_io_channel *ch, struct spdk_bdev_io *bdev_io)
474 {
475 	struct raid_bdev_io *raid_io = (struct raid_bdev_io *)bdev_io->driver_ctx;
476 
477 	raid_io->raid_bdev = bdev_io->bdev->ctxt;
478 	raid_io->raid_ch = spdk_io_channel_get_ctx(ch);
479 	raid_io->base_bdev_io_remaining = 0;
480 	raid_io->base_bdev_io_submitted = 0;
481 	raid_io->base_bdev_io_status = SPDK_BDEV_IO_STATUS_SUCCESS;
482 
483 	switch (bdev_io->type) {
484 	case SPDK_BDEV_IO_TYPE_READ:
485 		spdk_bdev_io_get_buf(bdev_io, raid_bdev_get_buf_cb,
486 				     bdev_io->u.bdev.num_blocks * bdev_io->bdev->blocklen);
487 		break;
488 	case SPDK_BDEV_IO_TYPE_WRITE:
489 		raid_io->raid_bdev->module->submit_rw_request(raid_io);
490 		break;
491 
492 	case SPDK_BDEV_IO_TYPE_RESET:
493 		raid_bdev_submit_reset_request(raid_io);
494 		break;
495 
496 	case SPDK_BDEV_IO_TYPE_FLUSH:
497 	case SPDK_BDEV_IO_TYPE_UNMAP:
498 		raid_io->raid_bdev->module->submit_null_payload_request(raid_io);
499 		break;
500 
501 	default:
502 		SPDK_ERRLOG("submit request, invalid io type %u\n", bdev_io->type);
503 		raid_bdev_io_complete(raid_io, SPDK_BDEV_IO_STATUS_FAILED);
504 		break;
505 	}
506 }
507 
508 /*
509  * brief:
510  * _raid_bdev_io_type_supported checks whether io_type is supported in
511  * all base bdev modules of raid bdev module. If anyone among the base_bdevs
512  * doesn't support, the raid device doesn't supports.
513  *
514  * params:
515  * raid_bdev - pointer to raid bdev context
516  * io_type - io type
517  * returns:
518  * true - io_type is supported
519  * false - io_type is not supported
520  */
521 inline static bool
522 _raid_bdev_io_type_supported(struct raid_bdev *raid_bdev, enum spdk_bdev_io_type io_type)
523 {
524 	struct raid_base_bdev_info *base_info;
525 
526 	if (io_type == SPDK_BDEV_IO_TYPE_FLUSH ||
527 	    io_type == SPDK_BDEV_IO_TYPE_UNMAP) {
528 		if (raid_bdev->module->submit_null_payload_request == NULL) {
529 			return false;
530 		}
531 	}
532 
533 	RAID_FOR_EACH_BASE_BDEV(raid_bdev, base_info) {
534 		if (base_info->desc == NULL) {
535 			continue;
536 		}
537 
538 		if (spdk_bdev_io_type_supported(spdk_bdev_desc_get_bdev(base_info->desc), io_type) == false) {
539 			return false;
540 		}
541 	}
542 
543 	return true;
544 }
545 
546 /*
547  * brief:
548  * raid_bdev_io_type_supported is the io_supported function for bdev function
549  * table which returns whether the particular io type is supported or not by
550  * raid bdev module
551  * params:
552  * ctx - pointer to raid bdev context
553  * type - io type
554  * returns:
555  * true - io_type is supported
556  * false - io_type is not supported
557  */
558 static bool
559 raid_bdev_io_type_supported(void *ctx, enum spdk_bdev_io_type io_type)
560 {
561 	switch (io_type) {
562 	case SPDK_BDEV_IO_TYPE_READ:
563 	case SPDK_BDEV_IO_TYPE_WRITE:
564 		return true;
565 
566 	case SPDK_BDEV_IO_TYPE_FLUSH:
567 	case SPDK_BDEV_IO_TYPE_RESET:
568 	case SPDK_BDEV_IO_TYPE_UNMAP:
569 		return _raid_bdev_io_type_supported(ctx, io_type);
570 
571 	default:
572 		return false;
573 	}
574 
575 	return false;
576 }
577 
578 /*
579  * brief:
580  * raid_bdev_get_io_channel is the get_io_channel function table pointer for
581  * raid bdev. This is used to return the io channel for this raid bdev
582  * params:
583  * ctxt - pointer to raid_bdev
584  * returns:
585  * pointer to io channel for raid bdev
586  */
587 static struct spdk_io_channel *
588 raid_bdev_get_io_channel(void *ctxt)
589 {
590 	struct raid_bdev *raid_bdev = ctxt;
591 
592 	return spdk_get_io_channel(raid_bdev);
593 }
594 
595 void
596 raid_bdev_write_info_json(struct raid_bdev *raid_bdev, struct spdk_json_write_ctx *w)
597 {
598 	struct raid_base_bdev_info *base_info;
599 	char uuid_str[SPDK_UUID_STRING_LEN];
600 
601 	assert(raid_bdev != NULL);
602 	assert(spdk_get_thread() == spdk_thread_get_app_thread());
603 
604 	spdk_uuid_fmt_lower(uuid_str, sizeof(uuid_str), &raid_bdev->bdev.uuid);
605 	spdk_json_write_named_string(w, "uuid", uuid_str);
606 	spdk_json_write_named_uint32(w, "strip_size_kb", raid_bdev->strip_size_kb);
607 	spdk_json_write_named_string(w, "state", raid_bdev_state_to_str(raid_bdev->state));
608 	spdk_json_write_named_string(w, "raid_level", raid_bdev_level_to_str(raid_bdev->level));
609 	spdk_json_write_named_bool(w, "superblock", raid_bdev->superblock_enabled);
610 	spdk_json_write_named_uint32(w, "num_base_bdevs", raid_bdev->num_base_bdevs);
611 	spdk_json_write_named_uint32(w, "num_base_bdevs_discovered", raid_bdev->num_base_bdevs_discovered);
612 	spdk_json_write_name(w, "base_bdevs_list");
613 	spdk_json_write_array_begin(w);
614 	RAID_FOR_EACH_BASE_BDEV(raid_bdev, base_info) {
615 		if (base_info->desc) {
616 			spdk_json_write_string(w, spdk_bdev_desc_get_bdev(base_info->desc)->name);
617 		} else {
618 			spdk_json_write_null(w);
619 		}
620 	}
621 	spdk_json_write_array_end(w);
622 }
623 
624 /*
625  * brief:
626  * raid_bdev_dump_info_json is the function table pointer for raid bdev
627  * params:
628  * ctx - pointer to raid_bdev
629  * w - pointer to json context
630  * returns:
631  * 0 - success
632  * non zero - failure
633  */
634 static int
635 raid_bdev_dump_info_json(void *ctx, struct spdk_json_write_ctx *w)
636 {
637 	struct raid_bdev *raid_bdev = ctx;
638 
639 	SPDK_DEBUGLOG(bdev_raid, "raid_bdev_dump_config_json\n");
640 
641 	/* Dump the raid bdev configuration related information */
642 	spdk_json_write_named_object_begin(w, "raid");
643 	raid_bdev_write_info_json(raid_bdev, w);
644 	spdk_json_write_object_end(w);
645 
646 	return 0;
647 }
648 
649 /*
650  * brief:
651  * raid_bdev_write_config_json is the function table pointer for raid bdev
652  * params:
653  * bdev - pointer to spdk_bdev
654  * w - pointer to json context
655  * returns:
656  * none
657  */
658 static void
659 raid_bdev_write_config_json(struct spdk_bdev *bdev, struct spdk_json_write_ctx *w)
660 {
661 	struct raid_bdev *raid_bdev = bdev->ctxt;
662 	struct raid_base_bdev_info *base_info;
663 	char uuid_str[SPDK_UUID_STRING_LEN];
664 
665 	assert(spdk_get_thread() == spdk_thread_get_app_thread());
666 
667 	if (raid_bdev->superblock_enabled) {
668 		/* raid bdev configuration is stored in the superblock */
669 		return;
670 	}
671 
672 	spdk_json_write_object_begin(w);
673 
674 	spdk_json_write_named_string(w, "method", "bdev_raid_create");
675 
676 	spdk_json_write_named_object_begin(w, "params");
677 	spdk_json_write_named_string(w, "name", bdev->name);
678 	spdk_uuid_fmt_lower(uuid_str, sizeof(uuid_str), &raid_bdev->bdev.uuid);
679 	spdk_json_write_named_string(w, "uuid", uuid_str);
680 	spdk_json_write_named_uint32(w, "strip_size_kb", raid_bdev->strip_size_kb);
681 	spdk_json_write_named_string(w, "raid_level", raid_bdev_level_to_str(raid_bdev->level));
682 	spdk_json_write_named_bool(w, "superblock", raid_bdev->superblock_enabled);
683 
684 	spdk_json_write_named_array_begin(w, "base_bdevs");
685 	RAID_FOR_EACH_BASE_BDEV(raid_bdev, base_info) {
686 		if (base_info->desc) {
687 			spdk_json_write_string(w, spdk_bdev_desc_get_bdev(base_info->desc)->name);
688 		}
689 	}
690 	spdk_json_write_array_end(w);
691 	spdk_json_write_object_end(w);
692 
693 	spdk_json_write_object_end(w);
694 }
695 
696 static int
697 raid_bdev_get_memory_domains(void *ctx, struct spdk_memory_domain **domains, int array_size)
698 {
699 	struct raid_bdev *raid_bdev = ctx;
700 	struct raid_base_bdev_info *base_info;
701 	int domains_count = 0, rc = 0;
702 
703 	if (raid_bdev->module->memory_domains_supported == false) {
704 		return 0;
705 	}
706 
707 	spdk_spin_lock(&raid_bdev->base_bdev_lock);
708 
709 	/* First loop to get the number of memory domains */
710 	RAID_FOR_EACH_BASE_BDEV(raid_bdev, base_info) {
711 		if (base_info->desc == NULL) {
712 			continue;
713 		}
714 		rc = spdk_bdev_get_memory_domains(spdk_bdev_desc_get_bdev(base_info->desc), NULL, 0);
715 		if (rc < 0) {
716 			goto out;
717 		}
718 		domains_count += rc;
719 	}
720 
721 	if (!domains || array_size < domains_count) {
722 		goto out;
723 	}
724 
725 	RAID_FOR_EACH_BASE_BDEV(raid_bdev, base_info) {
726 		if (base_info->desc == NULL) {
727 			continue;
728 		}
729 		rc = spdk_bdev_get_memory_domains(spdk_bdev_desc_get_bdev(base_info->desc), domains, array_size);
730 		if (rc < 0) {
731 			goto out;
732 		}
733 		domains += rc;
734 		array_size -= rc;
735 	}
736 out:
737 	spdk_spin_unlock(&raid_bdev->base_bdev_lock);
738 
739 	if (rc < 0) {
740 		return rc;
741 	}
742 
743 	return domains_count;
744 }
745 
746 /* g_raid_bdev_fn_table is the function table for raid bdev */
747 static const struct spdk_bdev_fn_table g_raid_bdev_fn_table = {
748 	.destruct		= raid_bdev_destruct,
749 	.submit_request		= raid_bdev_submit_request,
750 	.io_type_supported	= raid_bdev_io_type_supported,
751 	.get_io_channel		= raid_bdev_get_io_channel,
752 	.dump_info_json		= raid_bdev_dump_info_json,
753 	.write_config_json	= raid_bdev_write_config_json,
754 	.get_memory_domains	= raid_bdev_get_memory_domains,
755 };
756 
757 struct raid_bdev *
758 raid_bdev_find_by_name(const char *name)
759 {
760 	struct raid_bdev *raid_bdev;
761 
762 	TAILQ_FOREACH(raid_bdev, &g_raid_bdev_list, global_link) {
763 		if (strcmp(raid_bdev->bdev.name, name) == 0) {
764 			return raid_bdev;
765 		}
766 	}
767 
768 	return NULL;
769 }
770 
771 static struct {
772 	const char *name;
773 	enum raid_level value;
774 } g_raid_level_names[] = {
775 	{ "raid0", RAID0 },
776 	{ "0", RAID0 },
777 	{ "raid1", RAID1 },
778 	{ "1", RAID1 },
779 	{ "raid5f", RAID5F },
780 	{ "5f", RAID5F },
781 	{ "concat", CONCAT },
782 	{ }
783 };
784 
785 static struct {
786 	const char *name;
787 	enum raid_bdev_state value;
788 } g_raid_state_names[] = {
789 	{ "online", RAID_BDEV_STATE_ONLINE },
790 	{ "configuring", RAID_BDEV_STATE_CONFIGURING },
791 	{ "offline", RAID_BDEV_STATE_OFFLINE },
792 	{ }
793 };
794 
795 /* We have to use the typedef in the function declaration to appease astyle. */
796 typedef enum raid_level raid_level_t;
797 typedef enum raid_bdev_state raid_bdev_state_t;
798 
799 raid_level_t
800 raid_bdev_str_to_level(const char *str)
801 {
802 	unsigned int i;
803 
804 	assert(str != NULL);
805 
806 	for (i = 0; g_raid_level_names[i].name != NULL; i++) {
807 		if (strcasecmp(g_raid_level_names[i].name, str) == 0) {
808 			return g_raid_level_names[i].value;
809 		}
810 	}
811 
812 	return INVALID_RAID_LEVEL;
813 }
814 
815 const char *
816 raid_bdev_level_to_str(enum raid_level level)
817 {
818 	unsigned int i;
819 
820 	for (i = 0; g_raid_level_names[i].name != NULL; i++) {
821 		if (g_raid_level_names[i].value == level) {
822 			return g_raid_level_names[i].name;
823 		}
824 	}
825 
826 	return "";
827 }
828 
829 raid_bdev_state_t
830 raid_bdev_str_to_state(const char *str)
831 {
832 	unsigned int i;
833 
834 	assert(str != NULL);
835 
836 	for (i = 0; g_raid_state_names[i].name != NULL; i++) {
837 		if (strcasecmp(g_raid_state_names[i].name, str) == 0) {
838 			return g_raid_state_names[i].value;
839 		}
840 	}
841 
842 	return RAID_BDEV_STATE_MAX;
843 }
844 
845 const char *
846 raid_bdev_state_to_str(enum raid_bdev_state state)
847 {
848 	unsigned int i;
849 
850 	for (i = 0; g_raid_state_names[i].name != NULL; i++) {
851 		if (g_raid_state_names[i].value == state) {
852 			return g_raid_state_names[i].name;
853 		}
854 	}
855 
856 	assert(false);
857 	return "";
858 }
859 
860 /*
861  * brief:
862  * raid_bdev_fini_start is called when bdev layer is starting the
863  * shutdown process
864  * params:
865  * none
866  * returns:
867  * none
868  */
869 static void
870 raid_bdev_fini_start(void)
871 {
872 	SPDK_DEBUGLOG(bdev_raid, "raid_bdev_fini_start\n");
873 	g_shutdown_started = true;
874 }
875 
876 /*
877  * brief:
878  * raid_bdev_exit is called on raid bdev module exit time by bdev layer
879  * params:
880  * none
881  * returns:
882  * none
883  */
884 static void
885 raid_bdev_exit(void)
886 {
887 	struct raid_bdev *raid_bdev, *tmp;
888 
889 	SPDK_DEBUGLOG(bdev_raid, "raid_bdev_exit\n");
890 
891 	TAILQ_FOREACH_SAFE(raid_bdev, &g_raid_bdev_list, global_link, tmp) {
892 		raid_bdev_cleanup_and_free(raid_bdev);
893 	}
894 }
895 
896 /*
897  * brief:
898  * raid_bdev_get_ctx_size is used to return the context size of bdev_io for raid
899  * module
900  * params:
901  * none
902  * returns:
903  * size of spdk_bdev_io context for raid
904  */
905 static int
906 raid_bdev_get_ctx_size(void)
907 {
908 	SPDK_DEBUGLOG(bdev_raid, "raid_bdev_get_ctx_size\n");
909 	return sizeof(struct raid_bdev_io);
910 }
911 
912 static struct spdk_bdev_module g_raid_if = {
913 	.name = "raid",
914 	.module_init = raid_bdev_init,
915 	.fini_start = raid_bdev_fini_start,
916 	.module_fini = raid_bdev_exit,
917 	.get_ctx_size = raid_bdev_get_ctx_size,
918 	.examine_config = raid_bdev_examine,
919 	.async_init = false,
920 	.async_fini = false,
921 };
922 SPDK_BDEV_MODULE_REGISTER(raid, &g_raid_if)
923 
924 /*
925  * brief:
926  * raid_bdev_init is the initialization function for raid bdev module
927  * params:
928  * none
929  * returns:
930  * 0 - success
931  * non zero - failure
932  */
933 static int
934 raid_bdev_init(void)
935 {
936 	return 0;
937 }
938 
939 /*
940  * brief:
941  * raid_bdev_create allocates raid bdev based on passed configuration
942  * params:
943  * name - name for raid bdev
944  * strip_size - strip size in KB
945  * num_base_bdevs - number of base bdevs
946  * level - raid level
947  * superblock_enabled - true if raid should have superblock
948  * uuid - uuid to set for the bdev
949  * raid_bdev_out - the created raid bdev
950  * returns:
951  * 0 - success
952  * non zero - failure
953  */
954 int
955 raid_bdev_create(const char *name, uint32_t strip_size, uint8_t num_base_bdevs,
956 		 enum raid_level level, bool superblock_enabled, const struct spdk_uuid *uuid,
957 		 struct raid_bdev **raid_bdev_out)
958 {
959 	struct raid_bdev *raid_bdev;
960 	struct spdk_bdev *raid_bdev_gen;
961 	struct raid_bdev_module *module;
962 	struct raid_base_bdev_info *base_info;
963 	uint8_t min_operational;
964 
965 	if (raid_bdev_find_by_name(name) != NULL) {
966 		SPDK_ERRLOG("Duplicate raid bdev name found: %s\n", name);
967 		return -EEXIST;
968 	}
969 
970 	if (level == RAID1) {
971 		if (strip_size != 0) {
972 			SPDK_ERRLOG("Strip size is not supported by raid1\n");
973 			return -EINVAL;
974 		}
975 	} else if (spdk_u32_is_pow2(strip_size) == false) {
976 		SPDK_ERRLOG("Invalid strip size %" PRIu32 "\n", strip_size);
977 		return -EINVAL;
978 	}
979 
980 	module = raid_bdev_module_find(level);
981 	if (module == NULL) {
982 		SPDK_ERRLOG("Unsupported raid level '%d'\n", level);
983 		return -EINVAL;
984 	}
985 
986 	assert(module->base_bdevs_min != 0);
987 	if (num_base_bdevs < module->base_bdevs_min) {
988 		SPDK_ERRLOG("At least %u base devices required for %s\n",
989 			    module->base_bdevs_min,
990 			    raid_bdev_level_to_str(level));
991 		return -EINVAL;
992 	}
993 
994 	switch (module->base_bdevs_constraint.type) {
995 	case CONSTRAINT_MAX_BASE_BDEVS_REMOVED:
996 		min_operational = num_base_bdevs - module->base_bdevs_constraint.value;
997 		break;
998 	case CONSTRAINT_MIN_BASE_BDEVS_OPERATIONAL:
999 		min_operational = module->base_bdevs_constraint.value;
1000 		break;
1001 	case CONSTRAINT_UNSET:
1002 		if (module->base_bdevs_constraint.value != 0) {
1003 			SPDK_ERRLOG("Unexpected constraint value '%u' provided for raid bdev '%s'.\n",
1004 				    (uint8_t)module->base_bdevs_constraint.value, name);
1005 			return -EINVAL;
1006 		}
1007 		min_operational = num_base_bdevs;
1008 		break;
1009 	default:
1010 		SPDK_ERRLOG("Unrecognised constraint type '%u' in module for raid level '%s'.\n",
1011 			    (uint8_t)module->base_bdevs_constraint.type,
1012 			    raid_bdev_level_to_str(module->level));
1013 		return -EINVAL;
1014 	};
1015 
1016 	if (min_operational == 0 || min_operational > num_base_bdevs) {
1017 		SPDK_ERRLOG("Wrong constraint value for raid level '%s'.\n",
1018 			    raid_bdev_level_to_str(module->level));
1019 		return -EINVAL;
1020 	}
1021 
1022 	raid_bdev = calloc(1, sizeof(*raid_bdev));
1023 	if (!raid_bdev) {
1024 		SPDK_ERRLOG("Unable to allocate memory for raid bdev\n");
1025 		return -ENOMEM;
1026 	}
1027 
1028 	spdk_spin_init(&raid_bdev->base_bdev_lock);
1029 	raid_bdev->module = module;
1030 	raid_bdev->num_base_bdevs = num_base_bdevs;
1031 	raid_bdev->base_bdev_info = calloc(raid_bdev->num_base_bdevs,
1032 					   sizeof(struct raid_base_bdev_info));
1033 	if (!raid_bdev->base_bdev_info) {
1034 		SPDK_ERRLOG("Unable able to allocate base bdev info\n");
1035 		raid_bdev_free(raid_bdev);
1036 		return -ENOMEM;
1037 	}
1038 
1039 	RAID_FOR_EACH_BASE_BDEV(raid_bdev, base_info) {
1040 		base_info->raid_bdev = raid_bdev;
1041 	}
1042 
1043 	/* strip_size_kb is from the rpc param.  strip_size is in blocks and used
1044 	 * internally and set later.
1045 	 */
1046 	raid_bdev->strip_size = 0;
1047 	raid_bdev->strip_size_kb = strip_size;
1048 	raid_bdev->state = RAID_BDEV_STATE_CONFIGURING;
1049 	raid_bdev->level = level;
1050 	raid_bdev->min_base_bdevs_operational = min_operational;
1051 	raid_bdev->superblock_enabled = superblock_enabled;
1052 
1053 	raid_bdev_gen = &raid_bdev->bdev;
1054 
1055 	raid_bdev_gen->name = strdup(name);
1056 	if (!raid_bdev_gen->name) {
1057 		SPDK_ERRLOG("Unable to allocate name for raid\n");
1058 		raid_bdev_free(raid_bdev);
1059 		return -ENOMEM;
1060 	}
1061 
1062 	raid_bdev_gen->product_name = "Raid Volume";
1063 	raid_bdev_gen->ctxt = raid_bdev;
1064 	raid_bdev_gen->fn_table = &g_raid_bdev_fn_table;
1065 	raid_bdev_gen->module = &g_raid_if;
1066 	raid_bdev_gen->write_cache = 0;
1067 	spdk_uuid_copy(&raid_bdev_gen->uuid, uuid);
1068 
1069 	TAILQ_INSERT_TAIL(&g_raid_bdev_list, raid_bdev, global_link);
1070 
1071 	*raid_bdev_out = raid_bdev;
1072 
1073 	return 0;
1074 }
1075 
1076 /*
1077  * brief:
1078  * Check underlying block devices against support for metadata. Do not configure
1079  * md support when parameters from block devices are inconsistent.
1080  * params:
1081  * raid_bdev - pointer to raid bdev
1082  * returns:
1083  * 0 - The raid bdev md parameters were successfully configured.
1084  * non zero - Failed to configure md.
1085  */
1086 static int
1087 raid_bdev_configure_md(struct raid_bdev *raid_bdev)
1088 {
1089 	struct spdk_bdev *base_bdev;
1090 	uint8_t i;
1091 
1092 	for (i = 0; i < raid_bdev->num_base_bdevs; i++) {
1093 		base_bdev = spdk_bdev_desc_get_bdev(raid_bdev->base_bdev_info[i].desc);
1094 
1095 		/* Currently, RAID bdevs do not support DIF or DIX, so a RAID bdev cannot
1096 		 * be created on top of any bdev which supports it */
1097 		if (spdk_bdev_get_dif_type(base_bdev) != SPDK_DIF_DISABLE) {
1098 			SPDK_ERRLOG("at least one base bdev has DIF or DIX enabled "
1099 				    "- unsupported RAID configuration\n");
1100 			return -EPERM;
1101 		}
1102 
1103 		if (i == 0) {
1104 			raid_bdev->bdev.md_len = spdk_bdev_get_md_size(base_bdev);
1105 			raid_bdev->bdev.md_interleave = spdk_bdev_is_md_interleaved(base_bdev);
1106 			continue;
1107 		}
1108 
1109 		if (raid_bdev->bdev.md_len != spdk_bdev_get_md_size(base_bdev) ||
1110 		    raid_bdev->bdev.md_interleave != spdk_bdev_is_md_interleaved(base_bdev)) {
1111 			SPDK_ERRLOG("base bdevs are configured with different metadata formats\n");
1112 			return -EPERM;
1113 		}
1114 	}
1115 
1116 	return 0;
1117 }
1118 
1119 /*
1120  * brief:
1121  * If raid bdev config is complete, then only register the raid bdev to
1122  * bdev layer and remove this raid bdev from configuring list and
1123  * insert the raid bdev to configured list
1124  * params:
1125  * raid_bdev - pointer to raid bdev
1126  * returns:
1127  * 0 - success
1128  * non zero - failure
1129  */
1130 static int
1131 raid_bdev_configure(struct raid_bdev *raid_bdev)
1132 {
1133 	uint32_t blocklen = 0;
1134 	struct spdk_bdev *raid_bdev_gen;
1135 	struct raid_base_bdev_info *base_info;
1136 	struct spdk_bdev *base_bdev;
1137 	int rc = 0;
1138 
1139 	assert(raid_bdev->state == RAID_BDEV_STATE_CONFIGURING);
1140 	assert(raid_bdev->num_base_bdevs_discovered == raid_bdev->num_base_bdevs);
1141 
1142 	RAID_FOR_EACH_BASE_BDEV(raid_bdev, base_info) {
1143 		assert(base_info->desc != NULL);
1144 		base_bdev = spdk_bdev_desc_get_bdev(base_info->desc);
1145 		/* Check blocklen for all base bdevs that it should be same */
1146 		if (blocklen == 0) {
1147 			blocklen = base_bdev->blocklen;
1148 		} else if (blocklen != base_bdev->blocklen) {
1149 			/*
1150 			 * Assumption is that all the base bdevs for any raid bdev should
1151 			 * have same blocklen
1152 			 */
1153 			SPDK_ERRLOG("Blocklen of various bdevs not matching\n");
1154 			return -EINVAL;
1155 		}
1156 	}
1157 	assert(blocklen > 0);
1158 
1159 	/* The strip_size_kb is read in from user in KB. Convert to blocks here for
1160 	 * internal use.
1161 	 */
1162 	raid_bdev->strip_size = (raid_bdev->strip_size_kb * 1024) / blocklen;
1163 	if (raid_bdev->strip_size == 0 && raid_bdev->level != RAID1) {
1164 		SPDK_ERRLOG("Strip size cannot be smaller than the device block size\n");
1165 		return -EINVAL;
1166 	}
1167 	raid_bdev->strip_size_shift = spdk_u32log2(raid_bdev->strip_size);
1168 	raid_bdev->blocklen_shift = spdk_u32log2(blocklen);
1169 
1170 	raid_bdev_gen = &raid_bdev->bdev;
1171 	raid_bdev_gen->blocklen = blocklen;
1172 
1173 	rc = raid_bdev_configure_md(raid_bdev);
1174 	if (rc != 0) {
1175 		SPDK_ERRLOG("raid metadata configuration failed\n");
1176 		return rc;
1177 	}
1178 
1179 	rc = raid_bdev->module->start(raid_bdev);
1180 	if (rc != 0) {
1181 		SPDK_ERRLOG("raid module startup callback failed\n");
1182 		return rc;
1183 	}
1184 	raid_bdev->state = RAID_BDEV_STATE_ONLINE;
1185 	SPDK_DEBUGLOG(bdev_raid, "io device register %p\n", raid_bdev);
1186 	SPDK_DEBUGLOG(bdev_raid, "blockcnt %" PRIu64 ", blocklen %u\n",
1187 		      raid_bdev_gen->blockcnt, raid_bdev_gen->blocklen);
1188 	spdk_io_device_register(raid_bdev, raid_bdev_create_cb, raid_bdev_destroy_cb,
1189 				sizeof(struct raid_bdev_io_channel),
1190 				raid_bdev->bdev.name);
1191 	rc = spdk_bdev_register(raid_bdev_gen);
1192 	if (rc != 0) {
1193 		SPDK_ERRLOG("Unable to register raid bdev and stay at configuring state\n");
1194 		if (raid_bdev->module->stop != NULL) {
1195 			raid_bdev->module->stop(raid_bdev);
1196 		}
1197 		spdk_io_device_unregister(raid_bdev, NULL);
1198 		raid_bdev->state = RAID_BDEV_STATE_CONFIGURING;
1199 		return rc;
1200 	}
1201 	SPDK_DEBUGLOG(bdev_raid, "raid bdev generic %p\n", raid_bdev_gen);
1202 	SPDK_DEBUGLOG(bdev_raid, "raid bdev is created with name %s, raid_bdev %p\n",
1203 		      raid_bdev_gen->name, raid_bdev);
1204 
1205 	return 0;
1206 }
1207 
1208 /*
1209  * brief:
1210  * If raid bdev is online and registered, change the bdev state to
1211  * configuring and unregister this raid device. Queue this raid device
1212  * in configuring list
1213  * params:
1214  * raid_bdev - pointer to raid bdev
1215  * cb_fn - callback function
1216  * cb_arg - argument to callback function
1217  * returns:
1218  * none
1219  */
1220 static void
1221 raid_bdev_deconfigure(struct raid_bdev *raid_bdev, raid_bdev_destruct_cb cb_fn,
1222 		      void *cb_arg)
1223 {
1224 	if (raid_bdev->state != RAID_BDEV_STATE_ONLINE) {
1225 		if (cb_fn) {
1226 			cb_fn(cb_arg, 0);
1227 		}
1228 		return;
1229 	}
1230 
1231 	raid_bdev->state = RAID_BDEV_STATE_OFFLINE;
1232 	assert(raid_bdev->num_base_bdevs_discovered);
1233 	SPDK_DEBUGLOG(bdev_raid, "raid bdev state changing from online to offline\n");
1234 
1235 	spdk_bdev_unregister(&raid_bdev->bdev, cb_fn, cb_arg);
1236 }
1237 
1238 /*
1239  * brief:
1240  * raid_bdev_find_base_info_by_bdev function finds the base bdev info by bdev.
1241  * params:
1242  * base_bdev - pointer to base bdev
1243  * returns:
1244  * base bdev info if found, otherwise NULL.
1245  */
1246 static struct raid_base_bdev_info *
1247 raid_bdev_find_base_info_by_bdev(struct spdk_bdev *base_bdev)
1248 {
1249 	struct raid_bdev *raid_bdev;
1250 	struct raid_base_bdev_info *base_info;
1251 
1252 	TAILQ_FOREACH(raid_bdev, &g_raid_bdev_list, global_link) {
1253 		RAID_FOR_EACH_BASE_BDEV(raid_bdev, base_info) {
1254 			if (base_info->desc != NULL &&
1255 			    spdk_bdev_desc_get_bdev(base_info->desc) == base_bdev) {
1256 				return base_info;
1257 			}
1258 		}
1259 	}
1260 
1261 	return NULL;
1262 }
1263 
1264 static void
1265 raid_bdev_remove_base_bdev_on_unquiesced(void *ctx, int status)
1266 {
1267 	struct raid_base_bdev_info *base_info = ctx;
1268 	struct raid_bdev *raid_bdev = base_info->raid_bdev;
1269 
1270 	base_info->remove_scheduled = false;
1271 
1272 	if (status != 0) {
1273 		SPDK_ERRLOG("Failed to unquiesce raid bdev %s: %s\n",
1274 			    raid_bdev->bdev.name, spdk_strerror(-status));
1275 		goto out;
1276 	}
1277 
1278 	spdk_spin_lock(&raid_bdev->base_bdev_lock);
1279 	raid_bdev_free_base_bdev_resource(base_info);
1280 	spdk_spin_unlock(&raid_bdev->base_bdev_lock);
1281 out:
1282 	if (base_info->remove_cb != NULL) {
1283 		base_info->remove_cb(base_info->remove_cb_ctx, status);
1284 	}
1285 }
1286 
1287 static void
1288 raid_bdev_channel_remove_base_bdev(struct spdk_io_channel_iter *i)
1289 {
1290 	struct raid_base_bdev_info *base_info = spdk_io_channel_iter_get_ctx(i);
1291 	struct spdk_io_channel *ch = spdk_io_channel_iter_get_channel(i);
1292 	struct raid_bdev_io_channel *raid_ch = spdk_io_channel_get_ctx(ch);
1293 	uint8_t idx = base_info - base_info->raid_bdev->base_bdev_info;
1294 
1295 	SPDK_DEBUGLOG(bdev_raid, "slot: %u raid_ch: %p\n", idx, raid_ch);
1296 
1297 	if (raid_ch->base_channel[idx] != NULL) {
1298 		spdk_put_io_channel(raid_ch->base_channel[idx]);
1299 		raid_ch->base_channel[idx] = NULL;
1300 	}
1301 
1302 	spdk_for_each_channel_continue(i, 0);
1303 }
1304 
1305 static void
1306 raid_bdev_channels_remove_base_bdev_done(struct spdk_io_channel_iter *i, int status)
1307 {
1308 	struct raid_base_bdev_info *base_info = spdk_io_channel_iter_get_ctx(i);
1309 	struct raid_bdev *raid_bdev = base_info->raid_bdev;
1310 
1311 	spdk_bdev_unquiesce(&raid_bdev->bdev, &g_raid_if, raid_bdev_remove_base_bdev_on_unquiesced,
1312 			    base_info);
1313 }
1314 
1315 static void
1316 raid_bdev_remove_base_bdev_on_quiesced(void *ctx, int status)
1317 {
1318 	struct raid_base_bdev_info *base_info = ctx;
1319 	struct raid_bdev *raid_bdev = base_info->raid_bdev;
1320 
1321 	if (status != 0) {
1322 		SPDK_ERRLOG("Failed to quiesce raid bdev %s: %s\n",
1323 			    raid_bdev->bdev.name, spdk_strerror(-status));
1324 		base_info->remove_scheduled = false;
1325 		if (base_info->remove_cb != NULL) {
1326 			base_info->remove_cb(base_info->remove_cb_ctx, status);
1327 		}
1328 		return;
1329 	}
1330 
1331 	spdk_for_each_channel(raid_bdev, raid_bdev_channel_remove_base_bdev, base_info,
1332 			      raid_bdev_channels_remove_base_bdev_done);
1333 }
1334 
1335 /*
1336  * brief:
1337  * raid_bdev_remove_base_bdev function is called by below layers when base_bdev
1338  * is removed. This function checks if this base bdev is part of any raid bdev
1339  * or not. If yes, it takes necessary action on that particular raid bdev.
1340  * params:
1341  * base_bdev - pointer to base bdev which got removed
1342  * cb_fn - callback function
1343  * cb_arg - argument to callback function
1344  * returns:
1345  * 0 - success
1346  * non zero - failure
1347  */
1348 int
1349 raid_bdev_remove_base_bdev(struct spdk_bdev *base_bdev, raid_bdev_remove_base_bdev_cb cb_fn,
1350 			   void *cb_ctx)
1351 {
1352 	struct raid_bdev *raid_bdev;
1353 	struct raid_base_bdev_info *base_info;
1354 
1355 	SPDK_DEBUGLOG(bdev_raid, "%s\n", base_bdev->name);
1356 
1357 	/* Find the raid_bdev which has claimed this base_bdev */
1358 	base_info = raid_bdev_find_base_info_by_bdev(base_bdev);
1359 	if (!base_info) {
1360 		SPDK_ERRLOG("bdev to remove '%s' not found\n", base_bdev->name);
1361 		return -ENODEV;
1362 	}
1363 	raid_bdev = base_info->raid_bdev;
1364 
1365 	assert(spdk_get_thread() == spdk_thread_get_app_thread());
1366 
1367 	if (base_info->remove_scheduled) {
1368 		return 0;
1369 	}
1370 
1371 	assert(base_info->desc);
1372 	base_info->remove_scheduled = true;
1373 	base_info->remove_cb = cb_fn;
1374 	base_info->remove_cb_ctx = cb_ctx;
1375 
1376 	if (raid_bdev->state != RAID_BDEV_STATE_ONLINE) {
1377 		/*
1378 		 * As raid bdev is not registered yet or already unregistered,
1379 		 * so cleanup should be done here itself.
1380 		 */
1381 		raid_bdev_free_base_bdev_resource(base_info);
1382 		if (raid_bdev->num_base_bdevs_discovered == 0) {
1383 			/* There is no base bdev for this raid, so free the raid device. */
1384 			raid_bdev_cleanup_and_free(raid_bdev);
1385 		}
1386 	} else if (raid_bdev->num_base_bdevs_discovered == raid_bdev->min_base_bdevs_operational) {
1387 		/*
1388 		 * After this base bdev is removed there will not be enough base bdevs
1389 		 * to keep the raid bdev operational.
1390 		 */
1391 		raid_bdev_deconfigure(raid_bdev, cb_fn, cb_ctx);
1392 	} else {
1393 		int ret;
1394 
1395 		ret = spdk_bdev_quiesce(&raid_bdev->bdev, &g_raid_if,
1396 					raid_bdev_remove_base_bdev_on_quiesced, base_info);
1397 		if (ret != 0) {
1398 			base_info->remove_scheduled = false;
1399 		}
1400 	}
1401 
1402 	return 0;
1403 }
1404 
1405 /*
1406  * brief:
1407  * raid_bdev_resize_base_bdev function is called by below layers when base_bdev
1408  * is resized. This function checks if the smallest size of the base_bdevs is changed.
1409  * If yes, call module handler to resize the raid_bdev if implemented.
1410  * params:
1411  * base_bdev - pointer to base bdev which got resized.
1412  * returns:
1413  * none
1414  */
1415 static void
1416 raid_bdev_resize_base_bdev(struct spdk_bdev *base_bdev)
1417 {
1418 	struct raid_bdev *raid_bdev;
1419 	struct raid_base_bdev_info *base_info;
1420 
1421 	SPDK_DEBUGLOG(bdev_raid, "raid_bdev_resize_base_bdev\n");
1422 
1423 	base_info = raid_bdev_find_base_info_by_bdev(base_bdev);
1424 
1425 	/* Find the raid_bdev which has claimed this base_bdev */
1426 	if (!base_info) {
1427 		SPDK_ERRLOG("raid_bdev whose base_bdev '%s' not found\n", base_bdev->name);
1428 		return;
1429 	}
1430 	raid_bdev = base_info->raid_bdev;
1431 
1432 	assert(spdk_get_thread() == spdk_thread_get_app_thread());
1433 
1434 	SPDK_NOTICELOG("base_bdev '%s' was resized: old size %" PRIu64 ", new size %" PRIu64 "\n",
1435 		       base_bdev->name, base_info->blockcnt, base_bdev->blockcnt);
1436 
1437 	if (raid_bdev->module->resize) {
1438 		raid_bdev->module->resize(raid_bdev);
1439 	}
1440 }
1441 
1442 /*
1443  * brief:
1444  * raid_bdev_event_base_bdev function is called by below layers when base_bdev
1445  * triggers asynchronous event.
1446  * params:
1447  * type - event details.
1448  * bdev - bdev that triggered event.
1449  * event_ctx - context for event.
1450  * returns:
1451  * none
1452  */
1453 static void
1454 raid_bdev_event_base_bdev(enum spdk_bdev_event_type type, struct spdk_bdev *bdev,
1455 			  void *event_ctx)
1456 {
1457 	int rc;
1458 
1459 	switch (type) {
1460 	case SPDK_BDEV_EVENT_REMOVE:
1461 		rc = raid_bdev_remove_base_bdev(bdev, NULL, NULL);
1462 		if (rc != 0) {
1463 			SPDK_ERRLOG("Failed to remove base bdev %s: %s\n",
1464 				    spdk_bdev_get_name(bdev), spdk_strerror(-rc));
1465 		}
1466 		break;
1467 	case SPDK_BDEV_EVENT_RESIZE:
1468 		raid_bdev_resize_base_bdev(bdev);
1469 		break;
1470 	default:
1471 		SPDK_NOTICELOG("Unsupported bdev event: type %d\n", type);
1472 		break;
1473 	}
1474 }
1475 
1476 /*
1477  * brief:
1478  * Deletes the specified raid bdev
1479  * params:
1480  * raid_bdev - pointer to raid bdev
1481  * cb_fn - callback function
1482  * cb_arg - argument to callback function
1483  */
1484 void
1485 raid_bdev_delete(struct raid_bdev *raid_bdev, raid_bdev_destruct_cb cb_fn, void *cb_arg)
1486 {
1487 	struct raid_base_bdev_info *base_info;
1488 
1489 	SPDK_DEBUGLOG(bdev_raid, "delete raid bdev: %s\n", raid_bdev->bdev.name);
1490 
1491 	if (raid_bdev->destroy_started) {
1492 		SPDK_DEBUGLOG(bdev_raid, "destroying raid bdev %s is already started\n",
1493 			      raid_bdev->bdev.name);
1494 		if (cb_fn) {
1495 			cb_fn(cb_arg, -EALREADY);
1496 		}
1497 		return;
1498 	}
1499 
1500 	raid_bdev->destroy_started = true;
1501 
1502 	RAID_FOR_EACH_BASE_BDEV(raid_bdev, base_info) {
1503 		base_info->remove_scheduled = true;
1504 
1505 		if (raid_bdev->state != RAID_BDEV_STATE_ONLINE) {
1506 			/*
1507 			 * As raid bdev is not registered yet or already unregistered,
1508 			 * so cleanup should be done here itself.
1509 			 */
1510 			raid_bdev_free_base_bdev_resource(base_info);
1511 		}
1512 	}
1513 
1514 	if (raid_bdev->num_base_bdevs_discovered == 0) {
1515 		/* There is no base bdev for this raid, so free the raid device. */
1516 		raid_bdev_cleanup_and_free(raid_bdev);
1517 		if (cb_fn) {
1518 			cb_fn(cb_arg, 0);
1519 		}
1520 	} else {
1521 		raid_bdev_deconfigure(raid_bdev, cb_fn, cb_arg);
1522 	}
1523 }
1524 
1525 static int
1526 raid_bdev_configure_base_bdev(struct raid_base_bdev_info *base_info)
1527 {
1528 	struct raid_bdev *raid_bdev = base_info->raid_bdev;
1529 	struct spdk_bdev_desc *desc;
1530 	struct spdk_bdev *bdev;
1531 	int rc;
1532 
1533 	assert(spdk_get_thread() == spdk_thread_get_app_thread());
1534 	assert(base_info->name != NULL);
1535 	assert(base_info->desc == NULL);
1536 
1537 	rc = spdk_bdev_open_ext(base_info->name, true, raid_bdev_event_base_bdev, NULL, &desc);
1538 	if (rc != 0) {
1539 		if (rc != -ENODEV) {
1540 			SPDK_ERRLOG("Unable to create desc on bdev '%s'\n", base_info->name);
1541 		}
1542 		return rc;
1543 	}
1544 
1545 	bdev = spdk_bdev_desc_get_bdev(desc);
1546 
1547 	rc = spdk_bdev_module_claim_bdev(bdev, NULL, &g_raid_if);
1548 	if (rc != 0) {
1549 		SPDK_ERRLOG("Unable to claim this bdev as it is already claimed\n");
1550 		spdk_bdev_close(desc);
1551 		return rc;
1552 	}
1553 
1554 	SPDK_DEBUGLOG(bdev_raid, "bdev %s is claimed\n", bdev->name);
1555 
1556 	assert(raid_bdev->state != RAID_BDEV_STATE_ONLINE);
1557 
1558 	base_info->desc = desc;
1559 	base_info->blockcnt = bdev->blockcnt;
1560 	base_info->data_offset = 0;
1561 	base_info->data_size = bdev->blockcnt;
1562 	raid_bdev->num_base_bdevs_discovered++;
1563 	assert(raid_bdev->num_base_bdevs_discovered <= raid_bdev->num_base_bdevs);
1564 
1565 	if (raid_bdev->superblock_enabled) {
1566 		assert((RAID_BDEV_MIN_DATA_OFFSET_SIZE % bdev->blocklen) == 0);
1567 		base_info->data_offset = RAID_BDEV_MIN_DATA_OFFSET_SIZE / bdev->blocklen;
1568 
1569 		if (bdev->optimal_io_boundary) {
1570 			base_info->data_offset = spdk_divide_round_up(base_info->data_offset,
1571 						 bdev->optimal_io_boundary) * bdev->optimal_io_boundary;
1572 		}
1573 
1574 		if (base_info->data_offset >= bdev->blockcnt) {
1575 			SPDK_ERRLOG("Data offset %lu exceeds base bdev capacity %lu on bdev '%s'\n",
1576 				    base_info->data_offset, bdev->blockcnt, base_info->name);
1577 			return -EINVAL;
1578 		}
1579 
1580 		base_info->data_size = bdev->blockcnt - base_info->data_offset;
1581 	}
1582 
1583 	if (raid_bdev->num_base_bdevs_discovered == raid_bdev->num_base_bdevs) {
1584 		rc = raid_bdev_configure(raid_bdev);
1585 		if (rc != 0) {
1586 			SPDK_ERRLOG("Failed to configure raid bdev\n");
1587 			return rc;
1588 		}
1589 	}
1590 
1591 	return 0;
1592 }
1593 
1594 /*
1595  * brief:
1596  * raid_bdev_add_base_device function is the actual function which either adds
1597  * the nvme base device to existing raid bdev or create a new raid bdev. It also claims
1598  * the base device and keep the open descriptor.
1599  * params:
1600  * raid_bdev - pointer to raid bdev
1601  * name - name of the base bdev
1602  * slot - position to add base bdev
1603  * returns:
1604  * 0 - success
1605  * non zero - failure
1606  */
1607 int
1608 raid_bdev_add_base_device(struct raid_bdev *raid_bdev, const char *name, uint8_t slot)
1609 {
1610 	struct raid_base_bdev_info *base_info;
1611 	int rc;
1612 
1613 	if (slot >= raid_bdev->num_base_bdevs) {
1614 		return -EINVAL;
1615 	}
1616 
1617 	base_info = &raid_bdev->base_bdev_info[slot];
1618 
1619 	if (base_info->name != NULL) {
1620 		SPDK_ERRLOG("Slot %u on raid bdev '%s' already assigned to bdev '%s'\n",
1621 			    slot, raid_bdev->bdev.name, base_info->name);
1622 		return -EBUSY;
1623 	}
1624 
1625 	base_info->name = strdup(name);
1626 	if (base_info->name == NULL) {
1627 		return -ENOMEM;
1628 	}
1629 
1630 	rc = raid_bdev_configure_base_bdev(base_info);
1631 	if (rc != 0) {
1632 		if (rc != -ENODEV) {
1633 			SPDK_ERRLOG("Failed to allocate resource for bdev '%s'\n", name);
1634 		}
1635 		return rc;
1636 	}
1637 
1638 	return 0;
1639 }
1640 
1641 /*
1642  * brief:
1643  * raid_bdev_examine function is the examine function call by the below layers
1644  * like bdev_nvme layer. This function will check if this base bdev can be
1645  * claimed by this raid bdev or not.
1646  * params:
1647  * bdev - pointer to base bdev
1648  * returns:
1649  * none
1650  */
1651 static void
1652 raid_bdev_examine(struct spdk_bdev *bdev)
1653 {
1654 	struct raid_bdev *raid_bdev;
1655 	struct raid_base_bdev_info *base_info;
1656 
1657 	TAILQ_FOREACH(raid_bdev, &g_raid_bdev_list, global_link) {
1658 		RAID_FOR_EACH_BASE_BDEV(raid_bdev, base_info) {
1659 			if (base_info->desc == NULL && base_info->name != NULL &&
1660 			    strcmp(bdev->name, base_info->name) == 0) {
1661 				raid_bdev_configure_base_bdev(base_info);
1662 				break;
1663 			}
1664 		}
1665 	}
1666 
1667 	spdk_bdev_module_examine_done(&g_raid_if);
1668 }
1669 
1670 /* Log component for bdev raid bdev module */
1671 SPDK_LOG_REGISTER_COMPONENT(bdev_raid)
1672