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v6.2
   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * Copyright (C) 2017 Western Digital Corporation or its affiliates.
   4 *
   5 * This file is released under the GPL.
   6 */
   7
   8#include "dm-zoned.h"
   9
  10#include <linux/module.h>
  11
  12#define	DM_MSG_PREFIX		"zoned"
  13
  14#define DMZ_MIN_BIOS		8192
  15
  16/*
  17 * Zone BIO context.
  18 */
  19struct dmz_bioctx {
  20	struct dmz_dev		*dev;
  21	struct dm_zone		*zone;
  22	struct bio		*bio;
  23	refcount_t		ref;
  24};
  25
  26/*
  27 * Chunk work descriptor.
  28 */
  29struct dm_chunk_work {
  30	struct work_struct	work;
  31	refcount_t		refcount;
  32	struct dmz_target	*target;
  33	unsigned int		chunk;
  34	struct bio_list		bio_list;
  35};
  36
  37/*
  38 * Target descriptor.
  39 */
  40struct dmz_target {
  41	struct dm_dev		**ddev;
  42	unsigned int		nr_ddevs;
  43
  44	unsigned int		flags;
  45
  46	/* Zoned block device information */
  47	struct dmz_dev		*dev;
  48
  49	/* For metadata handling */
  50	struct dmz_metadata     *metadata;
  51
  52	/* For chunk work */
  53	struct radix_tree_root	chunk_rxtree;
  54	struct workqueue_struct *chunk_wq;
  55	struct mutex		chunk_lock;
  56
  57	/* For cloned BIOs to zones */
  58	struct bio_set		bio_set;
  59
  60	/* For flush */
  61	spinlock_t		flush_lock;
  62	struct bio_list		flush_list;
  63	struct delayed_work	flush_work;
  64	struct workqueue_struct *flush_wq;
  65};
  66
  67/*
  68 * Flush intervals (seconds).
  69 */
  70#define DMZ_FLUSH_PERIOD	(10 * HZ)
  71
  72/*
  73 * Target BIO completion.
  74 */
  75static inline void dmz_bio_endio(struct bio *bio, blk_status_t status)
  76{
  77	struct dmz_bioctx *bioctx =
  78		dm_per_bio_data(bio, sizeof(struct dmz_bioctx));
  79
  80	if (status != BLK_STS_OK && bio->bi_status == BLK_STS_OK)
  81		bio->bi_status = status;
  82	if (bioctx->dev && bio->bi_status != BLK_STS_OK)
  83		bioctx->dev->flags |= DMZ_CHECK_BDEV;
  84
  85	if (refcount_dec_and_test(&bioctx->ref)) {
  86		struct dm_zone *zone = bioctx->zone;
  87
  88		if (zone) {
  89			if (bio->bi_status != BLK_STS_OK &&
  90			    bio_op(bio) == REQ_OP_WRITE &&
  91			    dmz_is_seq(zone))
  92				set_bit(DMZ_SEQ_WRITE_ERR, &zone->flags);
  93			dmz_deactivate_zone(zone);
  94		}
  95		bio_endio(bio);
  96	}
  97}
  98
  99/*
 100 * Completion callback for an internally cloned target BIO. This terminates the
 101 * target BIO when there are no more references to its context.
 102 */
 103static void dmz_clone_endio(struct bio *clone)
 104{
 105	struct dmz_bioctx *bioctx = clone->bi_private;
 106	blk_status_t status = clone->bi_status;
 107
 108	bio_put(clone);
 109	dmz_bio_endio(bioctx->bio, status);
 110}
 111
 112/*
 113 * Issue a clone of a target BIO. The clone may only partially process the
 114 * original target BIO.
 115 */
 116static int dmz_submit_bio(struct dmz_target *dmz, struct dm_zone *zone,
 117			  struct bio *bio, sector_t chunk_block,
 118			  unsigned int nr_blocks)
 119{
 120	struct dmz_bioctx *bioctx =
 121		dm_per_bio_data(bio, sizeof(struct dmz_bioctx));
 122	struct dmz_dev *dev = zone->dev;
 123	struct bio *clone;
 124
 125	if (dev->flags & DMZ_BDEV_DYING)
 126		return -EIO;
 127
 128	clone = bio_alloc_clone(dev->bdev, bio, GFP_NOIO, &dmz->bio_set);
 129	if (!clone)
 130		return -ENOMEM;
 131
 
 132	bioctx->dev = dev;
 133	clone->bi_iter.bi_sector =
 134		dmz_start_sect(dmz->metadata, zone) + dmz_blk2sect(chunk_block);
 135	clone->bi_iter.bi_size = dmz_blk2sect(nr_blocks) << SECTOR_SHIFT;
 136	clone->bi_end_io = dmz_clone_endio;
 137	clone->bi_private = bioctx;
 138
 139	bio_advance(bio, clone->bi_iter.bi_size);
 140
 141	refcount_inc(&bioctx->ref);
 142	submit_bio_noacct(clone);
 143
 144	if (bio_op(bio) == REQ_OP_WRITE && dmz_is_seq(zone))
 145		zone->wp_block += nr_blocks;
 146
 147	return 0;
 148}
 149
 150/*
 151 * Zero out pages of discarded blocks accessed by a read BIO.
 152 */
 153static void dmz_handle_read_zero(struct dmz_target *dmz, struct bio *bio,
 154				 sector_t chunk_block, unsigned int nr_blocks)
 155{
 156	unsigned int size = nr_blocks << DMZ_BLOCK_SHIFT;
 157
 158	/* Clear nr_blocks */
 159	swap(bio->bi_iter.bi_size, size);
 160	zero_fill_bio(bio);
 161	swap(bio->bi_iter.bi_size, size);
 162
 163	bio_advance(bio, size);
 164}
 165
 166/*
 167 * Process a read BIO.
 168 */
 169static int dmz_handle_read(struct dmz_target *dmz, struct dm_zone *zone,
 170			   struct bio *bio)
 171{
 172	struct dmz_metadata *zmd = dmz->metadata;
 173	sector_t chunk_block = dmz_chunk_block(zmd, dmz_bio_block(bio));
 174	unsigned int nr_blocks = dmz_bio_blocks(bio);
 175	sector_t end_block = chunk_block + nr_blocks;
 176	struct dm_zone *rzone, *bzone;
 177	int ret;
 178
 179	/* Read into unmapped chunks need only zeroing the BIO buffer */
 180	if (!zone) {
 181		zero_fill_bio(bio);
 182		return 0;
 183	}
 184
 185	DMDEBUG("(%s): READ chunk %llu -> %s zone %u, block %llu, %u blocks",
 186		dmz_metadata_label(zmd),
 187		(unsigned long long)dmz_bio_chunk(zmd, bio),
 188		(dmz_is_rnd(zone) ? "RND" :
 189		 (dmz_is_cache(zone) ? "CACHE" : "SEQ")),
 190		zone->id,
 191		(unsigned long long)chunk_block, nr_blocks);
 192
 193	/* Check block validity to determine the read location */
 194	bzone = zone->bzone;
 195	while (chunk_block < end_block) {
 196		nr_blocks = 0;
 197		if (dmz_is_rnd(zone) || dmz_is_cache(zone) ||
 198		    chunk_block < zone->wp_block) {
 199			/* Test block validity in the data zone */
 200			ret = dmz_block_valid(zmd, zone, chunk_block);
 201			if (ret < 0)
 202				return ret;
 203			if (ret > 0) {
 204				/* Read data zone blocks */
 205				nr_blocks = ret;
 206				rzone = zone;
 207			}
 208		}
 209
 210		/*
 211		 * No valid blocks found in the data zone.
 212		 * Check the buffer zone, if there is one.
 213		 */
 214		if (!nr_blocks && bzone) {
 215			ret = dmz_block_valid(zmd, bzone, chunk_block);
 216			if (ret < 0)
 217				return ret;
 218			if (ret > 0) {
 219				/* Read buffer zone blocks */
 220				nr_blocks = ret;
 221				rzone = bzone;
 222			}
 223		}
 224
 225		if (nr_blocks) {
 226			/* Valid blocks found: read them */
 227			nr_blocks = min_t(unsigned int, nr_blocks,
 228					  end_block - chunk_block);
 229			ret = dmz_submit_bio(dmz, rzone, bio,
 230					     chunk_block, nr_blocks);
 231			if (ret)
 232				return ret;
 233			chunk_block += nr_blocks;
 234		} else {
 235			/* No valid block: zeroout the current BIO block */
 236			dmz_handle_read_zero(dmz, bio, chunk_block, 1);
 237			chunk_block++;
 238		}
 239	}
 240
 241	return 0;
 242}
 243
 244/*
 245 * Write blocks directly in a data zone, at the write pointer.
 246 * If a buffer zone is assigned, invalidate the blocks written
 247 * in place.
 248 */
 249static int dmz_handle_direct_write(struct dmz_target *dmz,
 250				   struct dm_zone *zone, struct bio *bio,
 251				   sector_t chunk_block,
 252				   unsigned int nr_blocks)
 253{
 254	struct dmz_metadata *zmd = dmz->metadata;
 255	struct dm_zone *bzone = zone->bzone;
 256	int ret;
 257
 258	if (dmz_is_readonly(zone))
 259		return -EROFS;
 260
 261	/* Submit write */
 262	ret = dmz_submit_bio(dmz, zone, bio, chunk_block, nr_blocks);
 263	if (ret)
 264		return ret;
 265
 266	/*
 267	 * Validate the blocks in the data zone and invalidate
 268	 * in the buffer zone, if there is one.
 269	 */
 270	ret = dmz_validate_blocks(zmd, zone, chunk_block, nr_blocks);
 271	if (ret == 0 && bzone)
 272		ret = dmz_invalidate_blocks(zmd, bzone, chunk_block, nr_blocks);
 273
 274	return ret;
 275}
 276
 277/*
 278 * Write blocks in the buffer zone of @zone.
 279 * If no buffer zone is assigned yet, get one.
 280 * Called with @zone write locked.
 281 */
 282static int dmz_handle_buffered_write(struct dmz_target *dmz,
 283				     struct dm_zone *zone, struct bio *bio,
 284				     sector_t chunk_block,
 285				     unsigned int nr_blocks)
 286{
 287	struct dmz_metadata *zmd = dmz->metadata;
 288	struct dm_zone *bzone;
 289	int ret;
 290
 291	/* Get the buffer zone. One will be allocated if needed */
 292	bzone = dmz_get_chunk_buffer(zmd, zone);
 293	if (IS_ERR(bzone))
 294		return PTR_ERR(bzone);
 295
 296	if (dmz_is_readonly(bzone))
 297		return -EROFS;
 298
 299	/* Submit write */
 300	ret = dmz_submit_bio(dmz, bzone, bio, chunk_block, nr_blocks);
 301	if (ret)
 302		return ret;
 303
 304	/*
 305	 * Validate the blocks in the buffer zone
 306	 * and invalidate in the data zone.
 307	 */
 308	ret = dmz_validate_blocks(zmd, bzone, chunk_block, nr_blocks);
 309	if (ret == 0 && chunk_block < zone->wp_block)
 310		ret = dmz_invalidate_blocks(zmd, zone, chunk_block, nr_blocks);
 311
 312	return ret;
 313}
 314
 315/*
 316 * Process a write BIO.
 317 */
 318static int dmz_handle_write(struct dmz_target *dmz, struct dm_zone *zone,
 319			    struct bio *bio)
 320{
 321	struct dmz_metadata *zmd = dmz->metadata;
 322	sector_t chunk_block = dmz_chunk_block(zmd, dmz_bio_block(bio));
 323	unsigned int nr_blocks = dmz_bio_blocks(bio);
 324
 325	if (!zone)
 326		return -ENOSPC;
 327
 328	DMDEBUG("(%s): WRITE chunk %llu -> %s zone %u, block %llu, %u blocks",
 329		dmz_metadata_label(zmd),
 330		(unsigned long long)dmz_bio_chunk(zmd, bio),
 331		(dmz_is_rnd(zone) ? "RND" :
 332		 (dmz_is_cache(zone) ? "CACHE" : "SEQ")),
 333		zone->id,
 334		(unsigned long long)chunk_block, nr_blocks);
 335
 336	if (dmz_is_rnd(zone) || dmz_is_cache(zone) ||
 337	    chunk_block == zone->wp_block) {
 338		/*
 339		 * zone is a random zone or it is a sequential zone
 340		 * and the BIO is aligned to the zone write pointer:
 341		 * direct write the zone.
 342		 */
 343		return dmz_handle_direct_write(dmz, zone, bio,
 344					       chunk_block, nr_blocks);
 345	}
 346
 347	/*
 348	 * This is an unaligned write in a sequential zone:
 349	 * use buffered write.
 350	 */
 351	return dmz_handle_buffered_write(dmz, zone, bio, chunk_block, nr_blocks);
 352}
 353
 354/*
 355 * Process a discard BIO.
 356 */
 357static int dmz_handle_discard(struct dmz_target *dmz, struct dm_zone *zone,
 358			      struct bio *bio)
 359{
 360	struct dmz_metadata *zmd = dmz->metadata;
 361	sector_t block = dmz_bio_block(bio);
 362	unsigned int nr_blocks = dmz_bio_blocks(bio);
 363	sector_t chunk_block = dmz_chunk_block(zmd, block);
 364	int ret = 0;
 365
 366	/* For unmapped chunks, there is nothing to do */
 367	if (!zone)
 368		return 0;
 369
 370	if (dmz_is_readonly(zone))
 371		return -EROFS;
 372
 373	DMDEBUG("(%s): DISCARD chunk %llu -> zone %u, block %llu, %u blocks",
 374		dmz_metadata_label(dmz->metadata),
 375		(unsigned long long)dmz_bio_chunk(zmd, bio),
 376		zone->id,
 377		(unsigned long long)chunk_block, nr_blocks);
 378
 379	/*
 380	 * Invalidate blocks in the data zone and its
 381	 * buffer zone if one is mapped.
 382	 */
 383	if (dmz_is_rnd(zone) || dmz_is_cache(zone) ||
 384	    chunk_block < zone->wp_block)
 385		ret = dmz_invalidate_blocks(zmd, zone, chunk_block, nr_blocks);
 386	if (ret == 0 && zone->bzone)
 387		ret = dmz_invalidate_blocks(zmd, zone->bzone,
 388					    chunk_block, nr_blocks);
 389	return ret;
 390}
 391
 392/*
 393 * Process a BIO.
 394 */
 395static void dmz_handle_bio(struct dmz_target *dmz, struct dm_chunk_work *cw,
 396			   struct bio *bio)
 397{
 398	struct dmz_bioctx *bioctx =
 399		dm_per_bio_data(bio, sizeof(struct dmz_bioctx));
 400	struct dmz_metadata *zmd = dmz->metadata;
 401	struct dm_zone *zone;
 402	int ret;
 403
 404	dmz_lock_metadata(zmd);
 405
 406	/*
 407	 * Get the data zone mapping the chunk. There may be no
 408	 * mapping for read and discard. If a mapping is obtained,
 409	 + the zone returned will be set to active state.
 410	 */
 411	zone = dmz_get_chunk_mapping(zmd, dmz_bio_chunk(zmd, bio),
 412				     bio_op(bio));
 413	if (IS_ERR(zone)) {
 414		ret = PTR_ERR(zone);
 415		goto out;
 416	}
 417
 418	/* Process the BIO */
 419	if (zone) {
 420		dmz_activate_zone(zone);
 421		bioctx->zone = zone;
 422		dmz_reclaim_bio_acc(zone->dev->reclaim);
 423	}
 424
 425	switch (bio_op(bio)) {
 426	case REQ_OP_READ:
 427		ret = dmz_handle_read(dmz, zone, bio);
 428		break;
 429	case REQ_OP_WRITE:
 430		ret = dmz_handle_write(dmz, zone, bio);
 431		break;
 432	case REQ_OP_DISCARD:
 433	case REQ_OP_WRITE_ZEROES:
 434		ret = dmz_handle_discard(dmz, zone, bio);
 435		break;
 436	default:
 437		DMERR("(%s): Unsupported BIO operation 0x%x",
 438		      dmz_metadata_label(dmz->metadata), bio_op(bio));
 439		ret = -EIO;
 440	}
 441
 442	/*
 443	 * Release the chunk mapping. This will check that the mapping
 444	 * is still valid, that is, that the zone used still has valid blocks.
 445	 */
 446	if (zone)
 447		dmz_put_chunk_mapping(zmd, zone);
 448out:
 449	dmz_bio_endio(bio, errno_to_blk_status(ret));
 450
 451	dmz_unlock_metadata(zmd);
 452}
 453
 454/*
 455 * Increment a chunk reference counter.
 456 */
 457static inline void dmz_get_chunk_work(struct dm_chunk_work *cw)
 458{
 459	refcount_inc(&cw->refcount);
 460}
 461
 462/*
 463 * Decrement a chunk work reference count and
 464 * free it if it becomes 0.
 465 */
 466static void dmz_put_chunk_work(struct dm_chunk_work *cw)
 467{
 468	if (refcount_dec_and_test(&cw->refcount)) {
 469		WARN_ON(!bio_list_empty(&cw->bio_list));
 470		radix_tree_delete(&cw->target->chunk_rxtree, cw->chunk);
 471		kfree(cw);
 472	}
 473}
 474
 475/*
 476 * Chunk BIO work function.
 477 */
 478static void dmz_chunk_work(struct work_struct *work)
 479{
 480	struct dm_chunk_work *cw = container_of(work, struct dm_chunk_work, work);
 481	struct dmz_target *dmz = cw->target;
 482	struct bio *bio;
 483
 484	mutex_lock(&dmz->chunk_lock);
 485
 486	/* Process the chunk BIOs */
 487	while ((bio = bio_list_pop(&cw->bio_list))) {
 488		mutex_unlock(&dmz->chunk_lock);
 489		dmz_handle_bio(dmz, cw, bio);
 490		mutex_lock(&dmz->chunk_lock);
 491		dmz_put_chunk_work(cw);
 492	}
 493
 494	/* Queueing the work incremented the work refcount */
 495	dmz_put_chunk_work(cw);
 496
 497	mutex_unlock(&dmz->chunk_lock);
 498}
 499
 500/*
 501 * Flush work.
 502 */
 503static void dmz_flush_work(struct work_struct *work)
 504{
 505	struct dmz_target *dmz = container_of(work, struct dmz_target, flush_work.work);
 506	struct bio *bio;
 507	int ret;
 508
 509	/* Flush dirty metadata blocks */
 510	ret = dmz_flush_metadata(dmz->metadata);
 511	if (ret)
 512		DMDEBUG("(%s): Metadata flush failed, rc=%d",
 513			dmz_metadata_label(dmz->metadata), ret);
 514
 515	/* Process queued flush requests */
 516	while (1) {
 517		spin_lock(&dmz->flush_lock);
 518		bio = bio_list_pop(&dmz->flush_list);
 519		spin_unlock(&dmz->flush_lock);
 520
 521		if (!bio)
 522			break;
 523
 524		dmz_bio_endio(bio, errno_to_blk_status(ret));
 525	}
 526
 527	queue_delayed_work(dmz->flush_wq, &dmz->flush_work, DMZ_FLUSH_PERIOD);
 528}
 529
 530/*
 531 * Get a chunk work and start it to process a new BIO.
 532 * If the BIO chunk has no work yet, create one.
 533 */
 534static int dmz_queue_chunk_work(struct dmz_target *dmz, struct bio *bio)
 535{
 536	unsigned int chunk = dmz_bio_chunk(dmz->metadata, bio);
 537	struct dm_chunk_work *cw;
 538	int ret = 0;
 539
 540	mutex_lock(&dmz->chunk_lock);
 541
 542	/* Get the BIO chunk work. If one is not active yet, create one */
 543	cw = radix_tree_lookup(&dmz->chunk_rxtree, chunk);
 544	if (cw) {
 545		dmz_get_chunk_work(cw);
 546	} else {
 547		/* Create a new chunk work */
 548		cw = kmalloc(sizeof(struct dm_chunk_work), GFP_NOIO);
 549		if (unlikely(!cw)) {
 550			ret = -ENOMEM;
 551			goto out;
 552		}
 553
 554		INIT_WORK(&cw->work, dmz_chunk_work);
 555		refcount_set(&cw->refcount, 1);
 556		cw->target = dmz;
 557		cw->chunk = chunk;
 558		bio_list_init(&cw->bio_list);
 559
 560		ret = radix_tree_insert(&dmz->chunk_rxtree, chunk, cw);
 561		if (unlikely(ret)) {
 562			kfree(cw);
 563			goto out;
 564		}
 565	}
 566
 567	bio_list_add(&cw->bio_list, bio);
 568
 569	if (queue_work(dmz->chunk_wq, &cw->work))
 570		dmz_get_chunk_work(cw);
 571out:
 572	mutex_unlock(&dmz->chunk_lock);
 573	return ret;
 574}
 575
 576/*
 577 * Check if the backing device is being removed. If it's on the way out,
 578 * start failing I/O. Reclaim and metadata components also call this
 579 * function to cleanly abort operation in the event of such failure.
 580 */
 581bool dmz_bdev_is_dying(struct dmz_dev *dmz_dev)
 582{
 583	if (dmz_dev->flags & DMZ_BDEV_DYING)
 584		return true;
 585
 586	if (dmz_dev->flags & DMZ_CHECK_BDEV)
 587		return !dmz_check_bdev(dmz_dev);
 588
 589	if (blk_queue_dying(bdev_get_queue(dmz_dev->bdev))) {
 590		dmz_dev_warn(dmz_dev, "Backing device queue dying");
 591		dmz_dev->flags |= DMZ_BDEV_DYING;
 592	}
 593
 594	return dmz_dev->flags & DMZ_BDEV_DYING;
 595}
 596
 597/*
 598 * Check the backing device availability. This detects such events as
 599 * backing device going offline due to errors, media removals, etc.
 600 * This check is less efficient than dmz_bdev_is_dying() and should
 601 * only be performed as a part of error handling.
 602 */
 603bool dmz_check_bdev(struct dmz_dev *dmz_dev)
 604{
 605	struct gendisk *disk;
 606
 607	dmz_dev->flags &= ~DMZ_CHECK_BDEV;
 608
 609	if (dmz_bdev_is_dying(dmz_dev))
 610		return false;
 611
 612	disk = dmz_dev->bdev->bd_disk;
 613	if (disk->fops->check_events &&
 614	    disk->fops->check_events(disk, 0) & DISK_EVENT_MEDIA_CHANGE) {
 615		dmz_dev_warn(dmz_dev, "Backing device offline");
 616		dmz_dev->flags |= DMZ_BDEV_DYING;
 617	}
 618
 619	return !(dmz_dev->flags & DMZ_BDEV_DYING);
 620}
 621
 622/*
 623 * Process a new BIO.
 624 */
 625static int dmz_map(struct dm_target *ti, struct bio *bio)
 626{
 627	struct dmz_target *dmz = ti->private;
 628	struct dmz_metadata *zmd = dmz->metadata;
 629	struct dmz_bioctx *bioctx = dm_per_bio_data(bio, sizeof(struct dmz_bioctx));
 630	sector_t sector = bio->bi_iter.bi_sector;
 631	unsigned int nr_sectors = bio_sectors(bio);
 632	sector_t chunk_sector;
 633	int ret;
 634
 635	if (dmz_dev_is_dying(zmd))
 636		return DM_MAPIO_KILL;
 637
 638	DMDEBUG("(%s): BIO op %d sector %llu + %u => chunk %llu, block %llu, %u blocks",
 639		dmz_metadata_label(zmd),
 640		bio_op(bio), (unsigned long long)sector, nr_sectors,
 641		(unsigned long long)dmz_bio_chunk(zmd, bio),
 642		(unsigned long long)dmz_chunk_block(zmd, dmz_bio_block(bio)),
 643		(unsigned int)dmz_bio_blocks(bio));
 644
 645	if (!nr_sectors && bio_op(bio) != REQ_OP_WRITE)
 646		return DM_MAPIO_REMAPPED;
 647
 648	/* The BIO should be block aligned */
 649	if ((nr_sectors & DMZ_BLOCK_SECTORS_MASK) || (sector & DMZ_BLOCK_SECTORS_MASK))
 650		return DM_MAPIO_KILL;
 651
 652	/* Initialize the BIO context */
 653	bioctx->dev = NULL;
 654	bioctx->zone = NULL;
 655	bioctx->bio = bio;
 656	refcount_set(&bioctx->ref, 1);
 657
 658	/* Set the BIO pending in the flush list */
 659	if (!nr_sectors && bio_op(bio) == REQ_OP_WRITE) {
 660		spin_lock(&dmz->flush_lock);
 661		bio_list_add(&dmz->flush_list, bio);
 662		spin_unlock(&dmz->flush_lock);
 663		mod_delayed_work(dmz->flush_wq, &dmz->flush_work, 0);
 664		return DM_MAPIO_SUBMITTED;
 665	}
 666
 667	/* Split zone BIOs to fit entirely into a zone */
 668	chunk_sector = sector & (dmz_zone_nr_sectors(zmd) - 1);
 669	if (chunk_sector + nr_sectors > dmz_zone_nr_sectors(zmd))
 670		dm_accept_partial_bio(bio, dmz_zone_nr_sectors(zmd) - chunk_sector);
 671
 672	/* Now ready to handle this BIO */
 673	ret = dmz_queue_chunk_work(dmz, bio);
 674	if (ret) {
 675		DMDEBUG("(%s): BIO op %d, can't process chunk %llu, err %i",
 676			dmz_metadata_label(zmd),
 677			bio_op(bio), (u64)dmz_bio_chunk(zmd, bio),
 678			ret);
 679		return DM_MAPIO_REQUEUE;
 680	}
 681
 682	return DM_MAPIO_SUBMITTED;
 683}
 684
 685/*
 686 * Get zoned device information.
 687 */
 688static int dmz_get_zoned_device(struct dm_target *ti, char *path,
 689				int idx, int nr_devs)
 690{
 691	struct dmz_target *dmz = ti->private;
 692	struct dm_dev *ddev;
 693	struct dmz_dev *dev;
 694	int ret;
 695	struct block_device *bdev;
 696
 697	/* Get the target device */
 698	ret = dm_get_device(ti, path, dm_table_get_mode(ti->table), &ddev);
 699	if (ret) {
 700		ti->error = "Get target device failed";
 701		return ret;
 702	}
 703
 704	bdev = ddev->bdev;
 705	if (bdev_zoned_model(bdev) == BLK_ZONED_NONE) {
 706		if (nr_devs == 1) {
 707			ti->error = "Invalid regular device";
 708			goto err;
 709		}
 710		if (idx != 0) {
 711			ti->error = "First device must be a regular device";
 712			goto err;
 713		}
 714		if (dmz->ddev[0]) {
 715			ti->error = "Too many regular devices";
 716			goto err;
 717		}
 718		dev = &dmz->dev[idx];
 719		dev->flags = DMZ_BDEV_REGULAR;
 720	} else {
 721		if (dmz->ddev[idx]) {
 722			ti->error = "Too many zoned devices";
 723			goto err;
 724		}
 725		if (nr_devs > 1 && idx == 0) {
 726			ti->error = "First device must be a regular device";
 727			goto err;
 728		}
 729		dev = &dmz->dev[idx];
 730	}
 731	dev->bdev = bdev;
 732	dev->dev_idx = idx;
 
 733
 734	dev->capacity = bdev_nr_sectors(bdev);
 735	if (ti->begin) {
 736		ti->error = "Partial mapping is not supported";
 737		goto err;
 738	}
 739
 740	dmz->ddev[idx] = ddev;
 741
 742	return 0;
 743err:
 744	dm_put_device(ti, ddev);
 745	return -EINVAL;
 746}
 747
 748/*
 749 * Cleanup zoned device information.
 750 */
 751static void dmz_put_zoned_device(struct dm_target *ti)
 752{
 753	struct dmz_target *dmz = ti->private;
 754	int i;
 755
 756	for (i = 0; i < dmz->nr_ddevs; i++) {
 757		if (dmz->ddev[i]) {
 758			dm_put_device(ti, dmz->ddev[i]);
 759			dmz->ddev[i] = NULL;
 760		}
 761	}
 762}
 763
 764static int dmz_fixup_devices(struct dm_target *ti)
 765{
 766	struct dmz_target *dmz = ti->private;
 767	struct dmz_dev *reg_dev = NULL;
 
 768	sector_t zone_nr_sectors = 0;
 769	int i;
 770
 771	/*
 772	 * When we have more than on devices, the first one must be a
 773	 * regular block device and the others zoned block devices.
 774	 */
 775	if (dmz->nr_ddevs > 1) {
 776		reg_dev = &dmz->dev[0];
 777		if (!(reg_dev->flags & DMZ_BDEV_REGULAR)) {
 778			ti->error = "Primary disk is not a regular device";
 779			return -EINVAL;
 780		}
 781		for (i = 1; i < dmz->nr_ddevs; i++) {
 782			struct dmz_dev *zoned_dev = &dmz->dev[i];
 783			struct block_device *bdev = zoned_dev->bdev;
 784
 785			if (zoned_dev->flags & DMZ_BDEV_REGULAR) {
 786				ti->error = "Secondary disk is not a zoned device";
 787				return -EINVAL;
 788			}
 
 789			if (zone_nr_sectors &&
 790			    zone_nr_sectors != bdev_zone_sectors(bdev)) {
 791				ti->error = "Zone nr sectors mismatch";
 792				return -EINVAL;
 793			}
 794			zone_nr_sectors = bdev_zone_sectors(bdev);
 795			zoned_dev->zone_nr_sectors = zone_nr_sectors;
 796			zoned_dev->nr_zones = bdev_nr_zones(bdev);
 
 797		}
 798	} else {
 799		struct dmz_dev *zoned_dev = &dmz->dev[0];
 800		struct block_device *bdev = zoned_dev->bdev;
 801
 802		if (zoned_dev->flags & DMZ_BDEV_REGULAR) {
 803			ti->error = "Disk is not a zoned device";
 804			return -EINVAL;
 805		}
 806		zoned_dev->zone_nr_sectors = bdev_zone_sectors(bdev);
 807		zoned_dev->nr_zones = bdev_nr_zones(bdev);
 
 808	}
 809
 810	if (reg_dev) {
 811		sector_t zone_offset;
 812
 813		reg_dev->zone_nr_sectors = zone_nr_sectors;
 814		reg_dev->nr_zones =
 815			DIV_ROUND_UP_SECTOR_T(reg_dev->capacity,
 816					      reg_dev->zone_nr_sectors);
 817		reg_dev->zone_offset = 0;
 818		zone_offset = reg_dev->nr_zones;
 819		for (i = 1; i < dmz->nr_ddevs; i++) {
 820			dmz->dev[i].zone_offset = zone_offset;
 821			zone_offset += dmz->dev[i].nr_zones;
 822		}
 823	}
 824	return 0;
 825}
 826
 827/*
 828 * Setup target.
 829 */
 830static int dmz_ctr(struct dm_target *ti, unsigned int argc, char **argv)
 831{
 832	struct dmz_target *dmz;
 833	int ret, i;
 834
 835	/* Check arguments */
 836	if (argc < 1) {
 837		ti->error = "Invalid argument count";
 838		return -EINVAL;
 839	}
 840
 841	/* Allocate and initialize the target descriptor */
 842	dmz = kzalloc(sizeof(struct dmz_target), GFP_KERNEL);
 843	if (!dmz) {
 844		ti->error = "Unable to allocate the zoned target descriptor";
 845		return -ENOMEM;
 846	}
 847	dmz->dev = kcalloc(argc, sizeof(struct dmz_dev), GFP_KERNEL);
 848	if (!dmz->dev) {
 849		ti->error = "Unable to allocate the zoned device descriptors";
 850		kfree(dmz);
 851		return -ENOMEM;
 852	}
 853	dmz->ddev = kcalloc(argc, sizeof(struct dm_dev *), GFP_KERNEL);
 854	if (!dmz->ddev) {
 855		ti->error = "Unable to allocate the dm device descriptors";
 856		ret = -ENOMEM;
 857		goto err;
 858	}
 859	dmz->nr_ddevs = argc;
 860
 861	ti->private = dmz;
 862
 863	/* Get the target zoned block device */
 864	for (i = 0; i < argc; i++) {
 865		ret = dmz_get_zoned_device(ti, argv[i], i, argc);
 866		if (ret)
 867			goto err_dev;
 868	}
 869	ret = dmz_fixup_devices(ti);
 870	if (ret)
 871		goto err_dev;
 872
 873	/* Initialize metadata */
 874	ret = dmz_ctr_metadata(dmz->dev, argc, &dmz->metadata,
 875			       dm_table_device_name(ti->table));
 876	if (ret) {
 877		ti->error = "Metadata initialization failed";
 878		goto err_dev;
 879	}
 880
 881	/* Set target (no write same support) */
 882	ti->max_io_len = dmz_zone_nr_sectors(dmz->metadata);
 883	ti->num_flush_bios = 1;
 884	ti->num_discard_bios = 1;
 885	ti->num_write_zeroes_bios = 1;
 886	ti->per_io_data_size = sizeof(struct dmz_bioctx);
 887	ti->flush_supported = true;
 888	ti->discards_supported = true;
 889
 890	/* The exposed capacity is the number of chunks that can be mapped */
 891	ti->len = (sector_t)dmz_nr_chunks(dmz->metadata) <<
 892		dmz_zone_nr_sectors_shift(dmz->metadata);
 893
 894	/* Zone BIO */
 895	ret = bioset_init(&dmz->bio_set, DMZ_MIN_BIOS, 0, 0);
 896	if (ret) {
 897		ti->error = "Create BIO set failed";
 898		goto err_meta;
 899	}
 900
 901	/* Chunk BIO work */
 902	mutex_init(&dmz->chunk_lock);
 903	INIT_RADIX_TREE(&dmz->chunk_rxtree, GFP_NOIO);
 904	dmz->chunk_wq = alloc_workqueue("dmz_cwq_%s",
 905					WQ_MEM_RECLAIM | WQ_UNBOUND, 0,
 906					dmz_metadata_label(dmz->metadata));
 907	if (!dmz->chunk_wq) {
 908		ti->error = "Create chunk workqueue failed";
 909		ret = -ENOMEM;
 910		goto err_bio;
 911	}
 912
 913	/* Flush work */
 914	spin_lock_init(&dmz->flush_lock);
 915	bio_list_init(&dmz->flush_list);
 916	INIT_DELAYED_WORK(&dmz->flush_work, dmz_flush_work);
 917	dmz->flush_wq = alloc_ordered_workqueue("dmz_fwq_%s", WQ_MEM_RECLAIM,
 918						dmz_metadata_label(dmz->metadata));
 919	if (!dmz->flush_wq) {
 920		ti->error = "Create flush workqueue failed";
 921		ret = -ENOMEM;
 922		goto err_cwq;
 923	}
 924	mod_delayed_work(dmz->flush_wq, &dmz->flush_work, DMZ_FLUSH_PERIOD);
 925
 926	/* Initialize reclaim */
 927	for (i = 0; i < dmz->nr_ddevs; i++) {
 928		ret = dmz_ctr_reclaim(dmz->metadata, &dmz->dev[i].reclaim, i);
 929		if (ret) {
 930			ti->error = "Zone reclaim initialization failed";
 931			goto err_fwq;
 932		}
 933	}
 934
 935	DMINFO("(%s): Target device: %llu 512-byte logical sectors (%llu blocks)",
 936	       dmz_metadata_label(dmz->metadata),
 937	       (unsigned long long)ti->len,
 938	       (unsigned long long)dmz_sect2blk(ti->len));
 939
 940	return 0;
 941err_fwq:
 942	destroy_workqueue(dmz->flush_wq);
 943err_cwq:
 944	destroy_workqueue(dmz->chunk_wq);
 945err_bio:
 946	mutex_destroy(&dmz->chunk_lock);
 947	bioset_exit(&dmz->bio_set);
 948err_meta:
 949	dmz_dtr_metadata(dmz->metadata);
 950err_dev:
 951	dmz_put_zoned_device(ti);
 952err:
 953	kfree(dmz->dev);
 954	kfree(dmz);
 955
 956	return ret;
 957}
 958
 959/*
 960 * Cleanup target.
 961 */
 962static void dmz_dtr(struct dm_target *ti)
 963{
 964	struct dmz_target *dmz = ti->private;
 965	int i;
 966
 
 967	destroy_workqueue(dmz->chunk_wq);
 968
 969	for (i = 0; i < dmz->nr_ddevs; i++)
 970		dmz_dtr_reclaim(dmz->dev[i].reclaim);
 971
 972	cancel_delayed_work_sync(&dmz->flush_work);
 973	destroy_workqueue(dmz->flush_wq);
 974
 975	(void) dmz_flush_metadata(dmz->metadata);
 976
 977	dmz_dtr_metadata(dmz->metadata);
 978
 979	bioset_exit(&dmz->bio_set);
 980
 981	dmz_put_zoned_device(ti);
 982
 983	mutex_destroy(&dmz->chunk_lock);
 984
 985	kfree(dmz->dev);
 986	kfree(dmz);
 987}
 988
 989/*
 990 * Setup target request queue limits.
 991 */
 992static void dmz_io_hints(struct dm_target *ti, struct queue_limits *limits)
 993{
 994	struct dmz_target *dmz = ti->private;
 995	unsigned int chunk_sectors = dmz_zone_nr_sectors(dmz->metadata);
 996
 997	limits->logical_block_size = DMZ_BLOCK_SIZE;
 998	limits->physical_block_size = DMZ_BLOCK_SIZE;
 999
1000	blk_limits_io_min(limits, DMZ_BLOCK_SIZE);
1001	blk_limits_io_opt(limits, DMZ_BLOCK_SIZE);
1002
1003	limits->discard_alignment = 0;
1004	limits->discard_granularity = DMZ_BLOCK_SIZE;
1005	limits->max_discard_sectors = chunk_sectors;
1006	limits->max_hw_discard_sectors = chunk_sectors;
1007	limits->max_write_zeroes_sectors = chunk_sectors;
1008
1009	/* FS hint to try to align to the device zone size */
1010	limits->chunk_sectors = chunk_sectors;
1011	limits->max_sectors = chunk_sectors;
1012
1013	/* We are exposing a drive-managed zoned block device */
1014	limits->zoned = BLK_ZONED_NONE;
1015}
1016
1017/*
1018 * Pass on ioctl to the backend device.
1019 */
1020static int dmz_prepare_ioctl(struct dm_target *ti, struct block_device **bdev)
1021{
1022	struct dmz_target *dmz = ti->private;
1023	struct dmz_dev *dev = &dmz->dev[0];
1024
1025	if (!dmz_check_bdev(dev))
1026		return -EIO;
1027
1028	*bdev = dev->bdev;
1029
1030	return 0;
1031}
1032
1033/*
1034 * Stop works on suspend.
1035 */
1036static void dmz_suspend(struct dm_target *ti)
1037{
1038	struct dmz_target *dmz = ti->private;
1039	int i;
1040
1041	flush_workqueue(dmz->chunk_wq);
1042	for (i = 0; i < dmz->nr_ddevs; i++)
1043		dmz_suspend_reclaim(dmz->dev[i].reclaim);
1044	cancel_delayed_work_sync(&dmz->flush_work);
1045}
1046
1047/*
1048 * Restart works on resume or if suspend failed.
1049 */
1050static void dmz_resume(struct dm_target *ti)
1051{
1052	struct dmz_target *dmz = ti->private;
1053	int i;
1054
1055	queue_delayed_work(dmz->flush_wq, &dmz->flush_work, DMZ_FLUSH_PERIOD);
1056	for (i = 0; i < dmz->nr_ddevs; i++)
1057		dmz_resume_reclaim(dmz->dev[i].reclaim);
1058}
1059
1060static int dmz_iterate_devices(struct dm_target *ti,
1061			       iterate_devices_callout_fn fn, void *data)
1062{
1063	struct dmz_target *dmz = ti->private;
1064	unsigned int zone_nr_sectors = dmz_zone_nr_sectors(dmz->metadata);
1065	sector_t capacity;
1066	int i, r;
1067
1068	for (i = 0; i < dmz->nr_ddevs; i++) {
1069		capacity = dmz->dev[i].capacity & ~(zone_nr_sectors - 1);
1070		r = fn(ti, dmz->ddev[i], 0, capacity, data);
1071		if (r)
1072			break;
1073	}
1074	return r;
1075}
1076
1077static void dmz_status(struct dm_target *ti, status_type_t type,
1078		       unsigned int status_flags, char *result,
1079		       unsigned int maxlen)
1080{
1081	struct dmz_target *dmz = ti->private;
1082	ssize_t sz = 0;
1083	char buf[BDEVNAME_SIZE];
1084	struct dmz_dev *dev;
1085	int i;
1086
1087	switch (type) {
1088	case STATUSTYPE_INFO:
1089		DMEMIT("%u zones %u/%u cache",
1090		       dmz_nr_zones(dmz->metadata),
1091		       dmz_nr_unmap_cache_zones(dmz->metadata),
1092		       dmz_nr_cache_zones(dmz->metadata));
1093		for (i = 0; i < dmz->nr_ddevs; i++) {
1094			/*
1095			 * For a multi-device setup the first device
1096			 * contains only cache zones.
1097			 */
1098			if ((i == 0) &&
1099			    (dmz_nr_cache_zones(dmz->metadata) > 0))
1100				continue;
1101			DMEMIT(" %u/%u random %u/%u sequential",
1102			       dmz_nr_unmap_rnd_zones(dmz->metadata, i),
1103			       dmz_nr_rnd_zones(dmz->metadata, i),
1104			       dmz_nr_unmap_seq_zones(dmz->metadata, i),
1105			       dmz_nr_seq_zones(dmz->metadata, i));
1106		}
1107		break;
1108	case STATUSTYPE_TABLE:
1109		dev = &dmz->dev[0];
1110		format_dev_t(buf, dev->bdev->bd_dev);
1111		DMEMIT("%s", buf);
1112		for (i = 1; i < dmz->nr_ddevs; i++) {
1113			dev = &dmz->dev[i];
1114			format_dev_t(buf, dev->bdev->bd_dev);
1115			DMEMIT(" %s", buf);
1116		}
1117		break;
1118	case STATUSTYPE_IMA:
1119		*result = '\0';
1120		break;
1121	}
1122	return;
1123}
1124
1125static int dmz_message(struct dm_target *ti, unsigned int argc, char **argv,
1126		       char *result, unsigned int maxlen)
1127{
1128	struct dmz_target *dmz = ti->private;
1129	int r = -EINVAL;
1130
1131	if (!strcasecmp(argv[0], "reclaim")) {
1132		int i;
1133
1134		for (i = 0; i < dmz->nr_ddevs; i++)
1135			dmz_schedule_reclaim(dmz->dev[i].reclaim);
1136		r = 0;
1137	} else
1138		DMERR("unrecognized message %s", argv[0]);
1139	return r;
1140}
1141
1142static struct target_type dmz_type = {
1143	.name		 = "zoned",
1144	.version	 = {2, 0, 0},
1145	.features	 = DM_TARGET_SINGLETON | DM_TARGET_MIXED_ZONED_MODEL,
1146	.module		 = THIS_MODULE,
1147	.ctr		 = dmz_ctr,
1148	.dtr		 = dmz_dtr,
1149	.map		 = dmz_map,
1150	.io_hints	 = dmz_io_hints,
1151	.prepare_ioctl	 = dmz_prepare_ioctl,
1152	.postsuspend	 = dmz_suspend,
1153	.resume		 = dmz_resume,
1154	.iterate_devices = dmz_iterate_devices,
1155	.status		 = dmz_status,
1156	.message	 = dmz_message,
1157};
1158
1159static int __init dmz_init(void)
1160{
1161	return dm_register_target(&dmz_type);
1162}
1163
1164static void __exit dmz_exit(void)
1165{
1166	dm_unregister_target(&dmz_type);
1167}
1168
1169module_init(dmz_init);
1170module_exit(dmz_exit);
1171
1172MODULE_DESCRIPTION(DM_NAME " target for zoned block devices");
1173MODULE_AUTHOR("Damien Le Moal <damien.lemoal@wdc.com>");
1174MODULE_LICENSE("GPL");
v5.9
   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * Copyright (C) 2017 Western Digital Corporation or its affiliates.
   4 *
   5 * This file is released under the GPL.
   6 */
   7
   8#include "dm-zoned.h"
   9
  10#include <linux/module.h>
  11
  12#define	DM_MSG_PREFIX		"zoned"
  13
  14#define DMZ_MIN_BIOS		8192
  15
  16/*
  17 * Zone BIO context.
  18 */
  19struct dmz_bioctx {
  20	struct dmz_dev		*dev;
  21	struct dm_zone		*zone;
  22	struct bio		*bio;
  23	refcount_t		ref;
  24};
  25
  26/*
  27 * Chunk work descriptor.
  28 */
  29struct dm_chunk_work {
  30	struct work_struct	work;
  31	refcount_t		refcount;
  32	struct dmz_target	*target;
  33	unsigned int		chunk;
  34	struct bio_list		bio_list;
  35};
  36
  37/*
  38 * Target descriptor.
  39 */
  40struct dmz_target {
  41	struct dm_dev		**ddev;
  42	unsigned int		nr_ddevs;
  43
  44	unsigned int		flags;
  45
  46	/* Zoned block device information */
  47	struct dmz_dev		*dev;
  48
  49	/* For metadata handling */
  50	struct dmz_metadata     *metadata;
  51
  52	/* For chunk work */
  53	struct radix_tree_root	chunk_rxtree;
  54	struct workqueue_struct *chunk_wq;
  55	struct mutex		chunk_lock;
  56
  57	/* For cloned BIOs to zones */
  58	struct bio_set		bio_set;
  59
  60	/* For flush */
  61	spinlock_t		flush_lock;
  62	struct bio_list		flush_list;
  63	struct delayed_work	flush_work;
  64	struct workqueue_struct *flush_wq;
  65};
  66
  67/*
  68 * Flush intervals (seconds).
  69 */
  70#define DMZ_FLUSH_PERIOD	(10 * HZ)
  71
  72/*
  73 * Target BIO completion.
  74 */
  75static inline void dmz_bio_endio(struct bio *bio, blk_status_t status)
  76{
  77	struct dmz_bioctx *bioctx =
  78		dm_per_bio_data(bio, sizeof(struct dmz_bioctx));
  79
  80	if (status != BLK_STS_OK && bio->bi_status == BLK_STS_OK)
  81		bio->bi_status = status;
  82	if (bioctx->dev && bio->bi_status != BLK_STS_OK)
  83		bioctx->dev->flags |= DMZ_CHECK_BDEV;
  84
  85	if (refcount_dec_and_test(&bioctx->ref)) {
  86		struct dm_zone *zone = bioctx->zone;
  87
  88		if (zone) {
  89			if (bio->bi_status != BLK_STS_OK &&
  90			    bio_op(bio) == REQ_OP_WRITE &&
  91			    dmz_is_seq(zone))
  92				set_bit(DMZ_SEQ_WRITE_ERR, &zone->flags);
  93			dmz_deactivate_zone(zone);
  94		}
  95		bio_endio(bio);
  96	}
  97}
  98
  99/*
 100 * Completion callback for an internally cloned target BIO. This terminates the
 101 * target BIO when there are no more references to its context.
 102 */
 103static void dmz_clone_endio(struct bio *clone)
 104{
 105	struct dmz_bioctx *bioctx = clone->bi_private;
 106	blk_status_t status = clone->bi_status;
 107
 108	bio_put(clone);
 109	dmz_bio_endio(bioctx->bio, status);
 110}
 111
 112/*
 113 * Issue a clone of a target BIO. The clone may only partially process the
 114 * original target BIO.
 115 */
 116static int dmz_submit_bio(struct dmz_target *dmz, struct dm_zone *zone,
 117			  struct bio *bio, sector_t chunk_block,
 118			  unsigned int nr_blocks)
 119{
 120	struct dmz_bioctx *bioctx =
 121		dm_per_bio_data(bio, sizeof(struct dmz_bioctx));
 122	struct dmz_dev *dev = zone->dev;
 123	struct bio *clone;
 124
 125	if (dev->flags & DMZ_BDEV_DYING)
 126		return -EIO;
 127
 128	clone = bio_clone_fast(bio, GFP_NOIO, &dmz->bio_set);
 129	if (!clone)
 130		return -ENOMEM;
 131
 132	bio_set_dev(clone, dev->bdev);
 133	bioctx->dev = dev;
 134	clone->bi_iter.bi_sector =
 135		dmz_start_sect(dmz->metadata, zone) + dmz_blk2sect(chunk_block);
 136	clone->bi_iter.bi_size = dmz_blk2sect(nr_blocks) << SECTOR_SHIFT;
 137	clone->bi_end_io = dmz_clone_endio;
 138	clone->bi_private = bioctx;
 139
 140	bio_advance(bio, clone->bi_iter.bi_size);
 141
 142	refcount_inc(&bioctx->ref);
 143	submit_bio_noacct(clone);
 144
 145	if (bio_op(bio) == REQ_OP_WRITE && dmz_is_seq(zone))
 146		zone->wp_block += nr_blocks;
 147
 148	return 0;
 149}
 150
 151/*
 152 * Zero out pages of discarded blocks accessed by a read BIO.
 153 */
 154static void dmz_handle_read_zero(struct dmz_target *dmz, struct bio *bio,
 155				 sector_t chunk_block, unsigned int nr_blocks)
 156{
 157	unsigned int size = nr_blocks << DMZ_BLOCK_SHIFT;
 158
 159	/* Clear nr_blocks */
 160	swap(bio->bi_iter.bi_size, size);
 161	zero_fill_bio(bio);
 162	swap(bio->bi_iter.bi_size, size);
 163
 164	bio_advance(bio, size);
 165}
 166
 167/*
 168 * Process a read BIO.
 169 */
 170static int dmz_handle_read(struct dmz_target *dmz, struct dm_zone *zone,
 171			   struct bio *bio)
 172{
 173	struct dmz_metadata *zmd = dmz->metadata;
 174	sector_t chunk_block = dmz_chunk_block(zmd, dmz_bio_block(bio));
 175	unsigned int nr_blocks = dmz_bio_blocks(bio);
 176	sector_t end_block = chunk_block + nr_blocks;
 177	struct dm_zone *rzone, *bzone;
 178	int ret;
 179
 180	/* Read into unmapped chunks need only zeroing the BIO buffer */
 181	if (!zone) {
 182		zero_fill_bio(bio);
 183		return 0;
 184	}
 185
 186	DMDEBUG("(%s): READ chunk %llu -> %s zone %u, block %llu, %u blocks",
 187		dmz_metadata_label(zmd),
 188		(unsigned long long)dmz_bio_chunk(zmd, bio),
 189		(dmz_is_rnd(zone) ? "RND" :
 190		 (dmz_is_cache(zone) ? "CACHE" : "SEQ")),
 191		zone->id,
 192		(unsigned long long)chunk_block, nr_blocks);
 193
 194	/* Check block validity to determine the read location */
 195	bzone = zone->bzone;
 196	while (chunk_block < end_block) {
 197		nr_blocks = 0;
 198		if (dmz_is_rnd(zone) || dmz_is_cache(zone) ||
 199		    chunk_block < zone->wp_block) {
 200			/* Test block validity in the data zone */
 201			ret = dmz_block_valid(zmd, zone, chunk_block);
 202			if (ret < 0)
 203				return ret;
 204			if (ret > 0) {
 205				/* Read data zone blocks */
 206				nr_blocks = ret;
 207				rzone = zone;
 208			}
 209		}
 210
 211		/*
 212		 * No valid blocks found in the data zone.
 213		 * Check the buffer zone, if there is one.
 214		 */
 215		if (!nr_blocks && bzone) {
 216			ret = dmz_block_valid(zmd, bzone, chunk_block);
 217			if (ret < 0)
 218				return ret;
 219			if (ret > 0) {
 220				/* Read buffer zone blocks */
 221				nr_blocks = ret;
 222				rzone = bzone;
 223			}
 224		}
 225
 226		if (nr_blocks) {
 227			/* Valid blocks found: read them */
 228			nr_blocks = min_t(unsigned int, nr_blocks,
 229					  end_block - chunk_block);
 230			ret = dmz_submit_bio(dmz, rzone, bio,
 231					     chunk_block, nr_blocks);
 232			if (ret)
 233				return ret;
 234			chunk_block += nr_blocks;
 235		} else {
 236			/* No valid block: zeroout the current BIO block */
 237			dmz_handle_read_zero(dmz, bio, chunk_block, 1);
 238			chunk_block++;
 239		}
 240	}
 241
 242	return 0;
 243}
 244
 245/*
 246 * Write blocks directly in a data zone, at the write pointer.
 247 * If a buffer zone is assigned, invalidate the blocks written
 248 * in place.
 249 */
 250static int dmz_handle_direct_write(struct dmz_target *dmz,
 251				   struct dm_zone *zone, struct bio *bio,
 252				   sector_t chunk_block,
 253				   unsigned int nr_blocks)
 254{
 255	struct dmz_metadata *zmd = dmz->metadata;
 256	struct dm_zone *bzone = zone->bzone;
 257	int ret;
 258
 259	if (dmz_is_readonly(zone))
 260		return -EROFS;
 261
 262	/* Submit write */
 263	ret = dmz_submit_bio(dmz, zone, bio, chunk_block, nr_blocks);
 264	if (ret)
 265		return ret;
 266
 267	/*
 268	 * Validate the blocks in the data zone and invalidate
 269	 * in the buffer zone, if there is one.
 270	 */
 271	ret = dmz_validate_blocks(zmd, zone, chunk_block, nr_blocks);
 272	if (ret == 0 && bzone)
 273		ret = dmz_invalidate_blocks(zmd, bzone, chunk_block, nr_blocks);
 274
 275	return ret;
 276}
 277
 278/*
 279 * Write blocks in the buffer zone of @zone.
 280 * If no buffer zone is assigned yet, get one.
 281 * Called with @zone write locked.
 282 */
 283static int dmz_handle_buffered_write(struct dmz_target *dmz,
 284				     struct dm_zone *zone, struct bio *bio,
 285				     sector_t chunk_block,
 286				     unsigned int nr_blocks)
 287{
 288	struct dmz_metadata *zmd = dmz->metadata;
 289	struct dm_zone *bzone;
 290	int ret;
 291
 292	/* Get the buffer zone. One will be allocated if needed */
 293	bzone = dmz_get_chunk_buffer(zmd, zone);
 294	if (IS_ERR(bzone))
 295		return PTR_ERR(bzone);
 296
 297	if (dmz_is_readonly(bzone))
 298		return -EROFS;
 299
 300	/* Submit write */
 301	ret = dmz_submit_bio(dmz, bzone, bio, chunk_block, nr_blocks);
 302	if (ret)
 303		return ret;
 304
 305	/*
 306	 * Validate the blocks in the buffer zone
 307	 * and invalidate in the data zone.
 308	 */
 309	ret = dmz_validate_blocks(zmd, bzone, chunk_block, nr_blocks);
 310	if (ret == 0 && chunk_block < zone->wp_block)
 311		ret = dmz_invalidate_blocks(zmd, zone, chunk_block, nr_blocks);
 312
 313	return ret;
 314}
 315
 316/*
 317 * Process a write BIO.
 318 */
 319static int dmz_handle_write(struct dmz_target *dmz, struct dm_zone *zone,
 320			    struct bio *bio)
 321{
 322	struct dmz_metadata *zmd = dmz->metadata;
 323	sector_t chunk_block = dmz_chunk_block(zmd, dmz_bio_block(bio));
 324	unsigned int nr_blocks = dmz_bio_blocks(bio);
 325
 326	if (!zone)
 327		return -ENOSPC;
 328
 329	DMDEBUG("(%s): WRITE chunk %llu -> %s zone %u, block %llu, %u blocks",
 330		dmz_metadata_label(zmd),
 331		(unsigned long long)dmz_bio_chunk(zmd, bio),
 332		(dmz_is_rnd(zone) ? "RND" :
 333		 (dmz_is_cache(zone) ? "CACHE" : "SEQ")),
 334		zone->id,
 335		(unsigned long long)chunk_block, nr_blocks);
 336
 337	if (dmz_is_rnd(zone) || dmz_is_cache(zone) ||
 338	    chunk_block == zone->wp_block) {
 339		/*
 340		 * zone is a random zone or it is a sequential zone
 341		 * and the BIO is aligned to the zone write pointer:
 342		 * direct write the zone.
 343		 */
 344		return dmz_handle_direct_write(dmz, zone, bio,
 345					       chunk_block, nr_blocks);
 346	}
 347
 348	/*
 349	 * This is an unaligned write in a sequential zone:
 350	 * use buffered write.
 351	 */
 352	return dmz_handle_buffered_write(dmz, zone, bio, chunk_block, nr_blocks);
 353}
 354
 355/*
 356 * Process a discard BIO.
 357 */
 358static int dmz_handle_discard(struct dmz_target *dmz, struct dm_zone *zone,
 359			      struct bio *bio)
 360{
 361	struct dmz_metadata *zmd = dmz->metadata;
 362	sector_t block = dmz_bio_block(bio);
 363	unsigned int nr_blocks = dmz_bio_blocks(bio);
 364	sector_t chunk_block = dmz_chunk_block(zmd, block);
 365	int ret = 0;
 366
 367	/* For unmapped chunks, there is nothing to do */
 368	if (!zone)
 369		return 0;
 370
 371	if (dmz_is_readonly(zone))
 372		return -EROFS;
 373
 374	DMDEBUG("(%s): DISCARD chunk %llu -> zone %u, block %llu, %u blocks",
 375		dmz_metadata_label(dmz->metadata),
 376		(unsigned long long)dmz_bio_chunk(zmd, bio),
 377		zone->id,
 378		(unsigned long long)chunk_block, nr_blocks);
 379
 380	/*
 381	 * Invalidate blocks in the data zone and its
 382	 * buffer zone if one is mapped.
 383	 */
 384	if (dmz_is_rnd(zone) || dmz_is_cache(zone) ||
 385	    chunk_block < zone->wp_block)
 386		ret = dmz_invalidate_blocks(zmd, zone, chunk_block, nr_blocks);
 387	if (ret == 0 && zone->bzone)
 388		ret = dmz_invalidate_blocks(zmd, zone->bzone,
 389					    chunk_block, nr_blocks);
 390	return ret;
 391}
 392
 393/*
 394 * Process a BIO.
 395 */
 396static void dmz_handle_bio(struct dmz_target *dmz, struct dm_chunk_work *cw,
 397			   struct bio *bio)
 398{
 399	struct dmz_bioctx *bioctx =
 400		dm_per_bio_data(bio, sizeof(struct dmz_bioctx));
 401	struct dmz_metadata *zmd = dmz->metadata;
 402	struct dm_zone *zone;
 403	int ret;
 404
 405	dmz_lock_metadata(zmd);
 406
 407	/*
 408	 * Get the data zone mapping the chunk. There may be no
 409	 * mapping for read and discard. If a mapping is obtained,
 410	 + the zone returned will be set to active state.
 411	 */
 412	zone = dmz_get_chunk_mapping(zmd, dmz_bio_chunk(zmd, bio),
 413				     bio_op(bio));
 414	if (IS_ERR(zone)) {
 415		ret = PTR_ERR(zone);
 416		goto out;
 417	}
 418
 419	/* Process the BIO */
 420	if (zone) {
 421		dmz_activate_zone(zone);
 422		bioctx->zone = zone;
 423		dmz_reclaim_bio_acc(zone->dev->reclaim);
 424	}
 425
 426	switch (bio_op(bio)) {
 427	case REQ_OP_READ:
 428		ret = dmz_handle_read(dmz, zone, bio);
 429		break;
 430	case REQ_OP_WRITE:
 431		ret = dmz_handle_write(dmz, zone, bio);
 432		break;
 433	case REQ_OP_DISCARD:
 434	case REQ_OP_WRITE_ZEROES:
 435		ret = dmz_handle_discard(dmz, zone, bio);
 436		break;
 437	default:
 438		DMERR("(%s): Unsupported BIO operation 0x%x",
 439		      dmz_metadata_label(dmz->metadata), bio_op(bio));
 440		ret = -EIO;
 441	}
 442
 443	/*
 444	 * Release the chunk mapping. This will check that the mapping
 445	 * is still valid, that is, that the zone used still has valid blocks.
 446	 */
 447	if (zone)
 448		dmz_put_chunk_mapping(zmd, zone);
 449out:
 450	dmz_bio_endio(bio, errno_to_blk_status(ret));
 451
 452	dmz_unlock_metadata(zmd);
 453}
 454
 455/*
 456 * Increment a chunk reference counter.
 457 */
 458static inline void dmz_get_chunk_work(struct dm_chunk_work *cw)
 459{
 460	refcount_inc(&cw->refcount);
 461}
 462
 463/*
 464 * Decrement a chunk work reference count and
 465 * free it if it becomes 0.
 466 */
 467static void dmz_put_chunk_work(struct dm_chunk_work *cw)
 468{
 469	if (refcount_dec_and_test(&cw->refcount)) {
 470		WARN_ON(!bio_list_empty(&cw->bio_list));
 471		radix_tree_delete(&cw->target->chunk_rxtree, cw->chunk);
 472		kfree(cw);
 473	}
 474}
 475
 476/*
 477 * Chunk BIO work function.
 478 */
 479static void dmz_chunk_work(struct work_struct *work)
 480{
 481	struct dm_chunk_work *cw = container_of(work, struct dm_chunk_work, work);
 482	struct dmz_target *dmz = cw->target;
 483	struct bio *bio;
 484
 485	mutex_lock(&dmz->chunk_lock);
 486
 487	/* Process the chunk BIOs */
 488	while ((bio = bio_list_pop(&cw->bio_list))) {
 489		mutex_unlock(&dmz->chunk_lock);
 490		dmz_handle_bio(dmz, cw, bio);
 491		mutex_lock(&dmz->chunk_lock);
 492		dmz_put_chunk_work(cw);
 493	}
 494
 495	/* Queueing the work incremented the work refcount */
 496	dmz_put_chunk_work(cw);
 497
 498	mutex_unlock(&dmz->chunk_lock);
 499}
 500
 501/*
 502 * Flush work.
 503 */
 504static void dmz_flush_work(struct work_struct *work)
 505{
 506	struct dmz_target *dmz = container_of(work, struct dmz_target, flush_work.work);
 507	struct bio *bio;
 508	int ret;
 509
 510	/* Flush dirty metadata blocks */
 511	ret = dmz_flush_metadata(dmz->metadata);
 512	if (ret)
 513		DMDEBUG("(%s): Metadata flush failed, rc=%d",
 514			dmz_metadata_label(dmz->metadata), ret);
 515
 516	/* Process queued flush requests */
 517	while (1) {
 518		spin_lock(&dmz->flush_lock);
 519		bio = bio_list_pop(&dmz->flush_list);
 520		spin_unlock(&dmz->flush_lock);
 521
 522		if (!bio)
 523			break;
 524
 525		dmz_bio_endio(bio, errno_to_blk_status(ret));
 526	}
 527
 528	queue_delayed_work(dmz->flush_wq, &dmz->flush_work, DMZ_FLUSH_PERIOD);
 529}
 530
 531/*
 532 * Get a chunk work and start it to process a new BIO.
 533 * If the BIO chunk has no work yet, create one.
 534 */
 535static int dmz_queue_chunk_work(struct dmz_target *dmz, struct bio *bio)
 536{
 537	unsigned int chunk = dmz_bio_chunk(dmz->metadata, bio);
 538	struct dm_chunk_work *cw;
 539	int ret = 0;
 540
 541	mutex_lock(&dmz->chunk_lock);
 542
 543	/* Get the BIO chunk work. If one is not active yet, create one */
 544	cw = radix_tree_lookup(&dmz->chunk_rxtree, chunk);
 545	if (cw) {
 546		dmz_get_chunk_work(cw);
 547	} else {
 548		/* Create a new chunk work */
 549		cw = kmalloc(sizeof(struct dm_chunk_work), GFP_NOIO);
 550		if (unlikely(!cw)) {
 551			ret = -ENOMEM;
 552			goto out;
 553		}
 554
 555		INIT_WORK(&cw->work, dmz_chunk_work);
 556		refcount_set(&cw->refcount, 1);
 557		cw->target = dmz;
 558		cw->chunk = chunk;
 559		bio_list_init(&cw->bio_list);
 560
 561		ret = radix_tree_insert(&dmz->chunk_rxtree, chunk, cw);
 562		if (unlikely(ret)) {
 563			kfree(cw);
 564			goto out;
 565		}
 566	}
 567
 568	bio_list_add(&cw->bio_list, bio);
 569
 570	if (queue_work(dmz->chunk_wq, &cw->work))
 571		dmz_get_chunk_work(cw);
 572out:
 573	mutex_unlock(&dmz->chunk_lock);
 574	return ret;
 575}
 576
 577/*
 578 * Check if the backing device is being removed. If it's on the way out,
 579 * start failing I/O. Reclaim and metadata components also call this
 580 * function to cleanly abort operation in the event of such failure.
 581 */
 582bool dmz_bdev_is_dying(struct dmz_dev *dmz_dev)
 583{
 584	if (dmz_dev->flags & DMZ_BDEV_DYING)
 585		return true;
 586
 587	if (dmz_dev->flags & DMZ_CHECK_BDEV)
 588		return !dmz_check_bdev(dmz_dev);
 589
 590	if (blk_queue_dying(bdev_get_queue(dmz_dev->bdev))) {
 591		dmz_dev_warn(dmz_dev, "Backing device queue dying");
 592		dmz_dev->flags |= DMZ_BDEV_DYING;
 593	}
 594
 595	return dmz_dev->flags & DMZ_BDEV_DYING;
 596}
 597
 598/*
 599 * Check the backing device availability. This detects such events as
 600 * backing device going offline due to errors, media removals, etc.
 601 * This check is less efficient than dmz_bdev_is_dying() and should
 602 * only be performed as a part of error handling.
 603 */
 604bool dmz_check_bdev(struct dmz_dev *dmz_dev)
 605{
 606	struct gendisk *disk;
 607
 608	dmz_dev->flags &= ~DMZ_CHECK_BDEV;
 609
 610	if (dmz_bdev_is_dying(dmz_dev))
 611		return false;
 612
 613	disk = dmz_dev->bdev->bd_disk;
 614	if (disk->fops->check_events &&
 615	    disk->fops->check_events(disk, 0) & DISK_EVENT_MEDIA_CHANGE) {
 616		dmz_dev_warn(dmz_dev, "Backing device offline");
 617		dmz_dev->flags |= DMZ_BDEV_DYING;
 618	}
 619
 620	return !(dmz_dev->flags & DMZ_BDEV_DYING);
 621}
 622
 623/*
 624 * Process a new BIO.
 625 */
 626static int dmz_map(struct dm_target *ti, struct bio *bio)
 627{
 628	struct dmz_target *dmz = ti->private;
 629	struct dmz_metadata *zmd = dmz->metadata;
 630	struct dmz_bioctx *bioctx = dm_per_bio_data(bio, sizeof(struct dmz_bioctx));
 631	sector_t sector = bio->bi_iter.bi_sector;
 632	unsigned int nr_sectors = bio_sectors(bio);
 633	sector_t chunk_sector;
 634	int ret;
 635
 636	if (dmz_dev_is_dying(zmd))
 637		return DM_MAPIO_KILL;
 638
 639	DMDEBUG("(%s): BIO op %d sector %llu + %u => chunk %llu, block %llu, %u blocks",
 640		dmz_metadata_label(zmd),
 641		bio_op(bio), (unsigned long long)sector, nr_sectors,
 642		(unsigned long long)dmz_bio_chunk(zmd, bio),
 643		(unsigned long long)dmz_chunk_block(zmd, dmz_bio_block(bio)),
 644		(unsigned int)dmz_bio_blocks(bio));
 645
 646	if (!nr_sectors && bio_op(bio) != REQ_OP_WRITE)
 647		return DM_MAPIO_REMAPPED;
 648
 649	/* The BIO should be block aligned */
 650	if ((nr_sectors & DMZ_BLOCK_SECTORS_MASK) || (sector & DMZ_BLOCK_SECTORS_MASK))
 651		return DM_MAPIO_KILL;
 652
 653	/* Initialize the BIO context */
 654	bioctx->dev = NULL;
 655	bioctx->zone = NULL;
 656	bioctx->bio = bio;
 657	refcount_set(&bioctx->ref, 1);
 658
 659	/* Set the BIO pending in the flush list */
 660	if (!nr_sectors && bio_op(bio) == REQ_OP_WRITE) {
 661		spin_lock(&dmz->flush_lock);
 662		bio_list_add(&dmz->flush_list, bio);
 663		spin_unlock(&dmz->flush_lock);
 664		mod_delayed_work(dmz->flush_wq, &dmz->flush_work, 0);
 665		return DM_MAPIO_SUBMITTED;
 666	}
 667
 668	/* Split zone BIOs to fit entirely into a zone */
 669	chunk_sector = sector & (dmz_zone_nr_sectors(zmd) - 1);
 670	if (chunk_sector + nr_sectors > dmz_zone_nr_sectors(zmd))
 671		dm_accept_partial_bio(bio, dmz_zone_nr_sectors(zmd) - chunk_sector);
 672
 673	/* Now ready to handle this BIO */
 674	ret = dmz_queue_chunk_work(dmz, bio);
 675	if (ret) {
 676		DMDEBUG("(%s): BIO op %d, can't process chunk %llu, err %i",
 677			dmz_metadata_label(zmd),
 678			bio_op(bio), (u64)dmz_bio_chunk(zmd, bio),
 679			ret);
 680		return DM_MAPIO_REQUEUE;
 681	}
 682
 683	return DM_MAPIO_SUBMITTED;
 684}
 685
 686/*
 687 * Get zoned device information.
 688 */
 689static int dmz_get_zoned_device(struct dm_target *ti, char *path,
 690				int idx, int nr_devs)
 691{
 692	struct dmz_target *dmz = ti->private;
 693	struct dm_dev *ddev;
 694	struct dmz_dev *dev;
 695	int ret;
 696	struct block_device *bdev;
 697
 698	/* Get the target device */
 699	ret = dm_get_device(ti, path, dm_table_get_mode(ti->table), &ddev);
 700	if (ret) {
 701		ti->error = "Get target device failed";
 702		return ret;
 703	}
 704
 705	bdev = ddev->bdev;
 706	if (bdev_zoned_model(bdev) == BLK_ZONED_NONE) {
 707		if (nr_devs == 1) {
 708			ti->error = "Invalid regular device";
 709			goto err;
 710		}
 711		if (idx != 0) {
 712			ti->error = "First device must be a regular device";
 713			goto err;
 714		}
 715		if (dmz->ddev[0]) {
 716			ti->error = "Too many regular devices";
 717			goto err;
 718		}
 719		dev = &dmz->dev[idx];
 720		dev->flags = DMZ_BDEV_REGULAR;
 721	} else {
 722		if (dmz->ddev[idx]) {
 723			ti->error = "Too many zoned devices";
 724			goto err;
 725		}
 726		if (nr_devs > 1 && idx == 0) {
 727			ti->error = "First device must be a regular device";
 728			goto err;
 729		}
 730		dev = &dmz->dev[idx];
 731	}
 732	dev->bdev = bdev;
 733	dev->dev_idx = idx;
 734	(void)bdevname(dev->bdev, dev->name);
 735
 736	dev->capacity = i_size_read(bdev->bd_inode) >> SECTOR_SHIFT;
 737	if (ti->begin) {
 738		ti->error = "Partial mapping is not supported";
 739		goto err;
 740	}
 741
 742	dmz->ddev[idx] = ddev;
 743
 744	return 0;
 745err:
 746	dm_put_device(ti, ddev);
 747	return -EINVAL;
 748}
 749
 750/*
 751 * Cleanup zoned device information.
 752 */
 753static void dmz_put_zoned_device(struct dm_target *ti)
 754{
 755	struct dmz_target *dmz = ti->private;
 756	int i;
 757
 758	for (i = 0; i < dmz->nr_ddevs; i++) {
 759		if (dmz->ddev[i]) {
 760			dm_put_device(ti, dmz->ddev[i]);
 761			dmz->ddev[i] = NULL;
 762		}
 763	}
 764}
 765
 766static int dmz_fixup_devices(struct dm_target *ti)
 767{
 768	struct dmz_target *dmz = ti->private;
 769	struct dmz_dev *reg_dev, *zoned_dev;
 770	struct request_queue *q;
 771	sector_t zone_nr_sectors = 0;
 772	int i;
 773
 774	/*
 775	 * When we have more than on devices, the first one must be a
 776	 * regular block device and the others zoned block devices.
 777	 */
 778	if (dmz->nr_ddevs > 1) {
 779		reg_dev = &dmz->dev[0];
 780		if (!(reg_dev->flags & DMZ_BDEV_REGULAR)) {
 781			ti->error = "Primary disk is not a regular device";
 782			return -EINVAL;
 783		}
 784		for (i = 1; i < dmz->nr_ddevs; i++) {
 785			zoned_dev = &dmz->dev[i];
 
 
 786			if (zoned_dev->flags & DMZ_BDEV_REGULAR) {
 787				ti->error = "Secondary disk is not a zoned device";
 788				return -EINVAL;
 789			}
 790			q = bdev_get_queue(zoned_dev->bdev);
 791			if (zone_nr_sectors &&
 792			    zone_nr_sectors != blk_queue_zone_sectors(q)) {
 793				ti->error = "Zone nr sectors mismatch";
 794				return -EINVAL;
 795			}
 796			zone_nr_sectors = blk_queue_zone_sectors(q);
 797			zoned_dev->zone_nr_sectors = zone_nr_sectors;
 798			zoned_dev->nr_zones =
 799				blkdev_nr_zones(zoned_dev->bdev->bd_disk);
 800		}
 801	} else {
 802		reg_dev = NULL;
 803		zoned_dev = &dmz->dev[0];
 
 804		if (zoned_dev->flags & DMZ_BDEV_REGULAR) {
 805			ti->error = "Disk is not a zoned device";
 806			return -EINVAL;
 807		}
 808		q = bdev_get_queue(zoned_dev->bdev);
 809		zoned_dev->zone_nr_sectors = blk_queue_zone_sectors(q);
 810		zoned_dev->nr_zones = blkdev_nr_zones(zoned_dev->bdev->bd_disk);
 811	}
 812
 813	if (reg_dev) {
 814		sector_t zone_offset;
 815
 816		reg_dev->zone_nr_sectors = zone_nr_sectors;
 817		reg_dev->nr_zones =
 818			DIV_ROUND_UP_SECTOR_T(reg_dev->capacity,
 819					      reg_dev->zone_nr_sectors);
 820		reg_dev->zone_offset = 0;
 821		zone_offset = reg_dev->nr_zones;
 822		for (i = 1; i < dmz->nr_ddevs; i++) {
 823			dmz->dev[i].zone_offset = zone_offset;
 824			zone_offset += dmz->dev[i].nr_zones;
 825		}
 826	}
 827	return 0;
 828}
 829
 830/*
 831 * Setup target.
 832 */
 833static int dmz_ctr(struct dm_target *ti, unsigned int argc, char **argv)
 834{
 835	struct dmz_target *dmz;
 836	int ret, i;
 837
 838	/* Check arguments */
 839	if (argc < 1) {
 840		ti->error = "Invalid argument count";
 841		return -EINVAL;
 842	}
 843
 844	/* Allocate and initialize the target descriptor */
 845	dmz = kzalloc(sizeof(struct dmz_target), GFP_KERNEL);
 846	if (!dmz) {
 847		ti->error = "Unable to allocate the zoned target descriptor";
 848		return -ENOMEM;
 849	}
 850	dmz->dev = kcalloc(argc, sizeof(struct dmz_dev), GFP_KERNEL);
 851	if (!dmz->dev) {
 852		ti->error = "Unable to allocate the zoned device descriptors";
 853		kfree(dmz);
 854		return -ENOMEM;
 855	}
 856	dmz->ddev = kcalloc(argc, sizeof(struct dm_dev *), GFP_KERNEL);
 857	if (!dmz->ddev) {
 858		ti->error = "Unable to allocate the dm device descriptors";
 859		ret = -ENOMEM;
 860		goto err;
 861	}
 862	dmz->nr_ddevs = argc;
 863
 864	ti->private = dmz;
 865
 866	/* Get the target zoned block device */
 867	for (i = 0; i < argc; i++) {
 868		ret = dmz_get_zoned_device(ti, argv[i], i, argc);
 869		if (ret)
 870			goto err_dev;
 871	}
 872	ret = dmz_fixup_devices(ti);
 873	if (ret)
 874		goto err_dev;
 875
 876	/* Initialize metadata */
 877	ret = dmz_ctr_metadata(dmz->dev, argc, &dmz->metadata,
 878			       dm_table_device_name(ti->table));
 879	if (ret) {
 880		ti->error = "Metadata initialization failed";
 881		goto err_dev;
 882	}
 883
 884	/* Set target (no write same support) */
 885	ti->max_io_len = dmz_zone_nr_sectors(dmz->metadata);
 886	ti->num_flush_bios = 1;
 887	ti->num_discard_bios = 1;
 888	ti->num_write_zeroes_bios = 1;
 889	ti->per_io_data_size = sizeof(struct dmz_bioctx);
 890	ti->flush_supported = true;
 891	ti->discards_supported = true;
 892
 893	/* The exposed capacity is the number of chunks that can be mapped */
 894	ti->len = (sector_t)dmz_nr_chunks(dmz->metadata) <<
 895		dmz_zone_nr_sectors_shift(dmz->metadata);
 896
 897	/* Zone BIO */
 898	ret = bioset_init(&dmz->bio_set, DMZ_MIN_BIOS, 0, 0);
 899	if (ret) {
 900		ti->error = "Create BIO set failed";
 901		goto err_meta;
 902	}
 903
 904	/* Chunk BIO work */
 905	mutex_init(&dmz->chunk_lock);
 906	INIT_RADIX_TREE(&dmz->chunk_rxtree, GFP_NOIO);
 907	dmz->chunk_wq = alloc_workqueue("dmz_cwq_%s",
 908					WQ_MEM_RECLAIM | WQ_UNBOUND, 0,
 909					dmz_metadata_label(dmz->metadata));
 910	if (!dmz->chunk_wq) {
 911		ti->error = "Create chunk workqueue failed";
 912		ret = -ENOMEM;
 913		goto err_bio;
 914	}
 915
 916	/* Flush work */
 917	spin_lock_init(&dmz->flush_lock);
 918	bio_list_init(&dmz->flush_list);
 919	INIT_DELAYED_WORK(&dmz->flush_work, dmz_flush_work);
 920	dmz->flush_wq = alloc_ordered_workqueue("dmz_fwq_%s", WQ_MEM_RECLAIM,
 921						dmz_metadata_label(dmz->metadata));
 922	if (!dmz->flush_wq) {
 923		ti->error = "Create flush workqueue failed";
 924		ret = -ENOMEM;
 925		goto err_cwq;
 926	}
 927	mod_delayed_work(dmz->flush_wq, &dmz->flush_work, DMZ_FLUSH_PERIOD);
 928
 929	/* Initialize reclaim */
 930	for (i = 0; i < dmz->nr_ddevs; i++) {
 931		ret = dmz_ctr_reclaim(dmz->metadata, &dmz->dev[i].reclaim, i);
 932		if (ret) {
 933			ti->error = "Zone reclaim initialization failed";
 934			goto err_fwq;
 935		}
 936	}
 937
 938	DMINFO("(%s): Target device: %llu 512-byte logical sectors (%llu blocks)",
 939	       dmz_metadata_label(dmz->metadata),
 940	       (unsigned long long)ti->len,
 941	       (unsigned long long)dmz_sect2blk(ti->len));
 942
 943	return 0;
 944err_fwq:
 945	destroy_workqueue(dmz->flush_wq);
 946err_cwq:
 947	destroy_workqueue(dmz->chunk_wq);
 948err_bio:
 949	mutex_destroy(&dmz->chunk_lock);
 950	bioset_exit(&dmz->bio_set);
 951err_meta:
 952	dmz_dtr_metadata(dmz->metadata);
 953err_dev:
 954	dmz_put_zoned_device(ti);
 955err:
 956	kfree(dmz->dev);
 957	kfree(dmz);
 958
 959	return ret;
 960}
 961
 962/*
 963 * Cleanup target.
 964 */
 965static void dmz_dtr(struct dm_target *ti)
 966{
 967	struct dmz_target *dmz = ti->private;
 968	int i;
 969
 970	flush_workqueue(dmz->chunk_wq);
 971	destroy_workqueue(dmz->chunk_wq);
 972
 973	for (i = 0; i < dmz->nr_ddevs; i++)
 974		dmz_dtr_reclaim(dmz->dev[i].reclaim);
 975
 976	cancel_delayed_work_sync(&dmz->flush_work);
 977	destroy_workqueue(dmz->flush_wq);
 978
 979	(void) dmz_flush_metadata(dmz->metadata);
 980
 981	dmz_dtr_metadata(dmz->metadata);
 982
 983	bioset_exit(&dmz->bio_set);
 984
 985	dmz_put_zoned_device(ti);
 986
 987	mutex_destroy(&dmz->chunk_lock);
 988
 989	kfree(dmz->dev);
 990	kfree(dmz);
 991}
 992
 993/*
 994 * Setup target request queue limits.
 995 */
 996static void dmz_io_hints(struct dm_target *ti, struct queue_limits *limits)
 997{
 998	struct dmz_target *dmz = ti->private;
 999	unsigned int chunk_sectors = dmz_zone_nr_sectors(dmz->metadata);
1000
1001	limits->logical_block_size = DMZ_BLOCK_SIZE;
1002	limits->physical_block_size = DMZ_BLOCK_SIZE;
1003
1004	blk_limits_io_min(limits, DMZ_BLOCK_SIZE);
1005	blk_limits_io_opt(limits, DMZ_BLOCK_SIZE);
1006
1007	limits->discard_alignment = DMZ_BLOCK_SIZE;
1008	limits->discard_granularity = DMZ_BLOCK_SIZE;
1009	limits->max_discard_sectors = chunk_sectors;
1010	limits->max_hw_discard_sectors = chunk_sectors;
1011	limits->max_write_zeroes_sectors = chunk_sectors;
1012
1013	/* FS hint to try to align to the device zone size */
1014	limits->chunk_sectors = chunk_sectors;
1015	limits->max_sectors = chunk_sectors;
1016
1017	/* We are exposing a drive-managed zoned block device */
1018	limits->zoned = BLK_ZONED_NONE;
1019}
1020
1021/*
1022 * Pass on ioctl to the backend device.
1023 */
1024static int dmz_prepare_ioctl(struct dm_target *ti, struct block_device **bdev)
1025{
1026	struct dmz_target *dmz = ti->private;
1027	struct dmz_dev *dev = &dmz->dev[0];
1028
1029	if (!dmz_check_bdev(dev))
1030		return -EIO;
1031
1032	*bdev = dev->bdev;
1033
1034	return 0;
1035}
1036
1037/*
1038 * Stop works on suspend.
1039 */
1040static void dmz_suspend(struct dm_target *ti)
1041{
1042	struct dmz_target *dmz = ti->private;
1043	int i;
1044
1045	flush_workqueue(dmz->chunk_wq);
1046	for (i = 0; i < dmz->nr_ddevs; i++)
1047		dmz_suspend_reclaim(dmz->dev[i].reclaim);
1048	cancel_delayed_work_sync(&dmz->flush_work);
1049}
1050
1051/*
1052 * Restart works on resume or if suspend failed.
1053 */
1054static void dmz_resume(struct dm_target *ti)
1055{
1056	struct dmz_target *dmz = ti->private;
1057	int i;
1058
1059	queue_delayed_work(dmz->flush_wq, &dmz->flush_work, DMZ_FLUSH_PERIOD);
1060	for (i = 0; i < dmz->nr_ddevs; i++)
1061		dmz_resume_reclaim(dmz->dev[i].reclaim);
1062}
1063
1064static int dmz_iterate_devices(struct dm_target *ti,
1065			       iterate_devices_callout_fn fn, void *data)
1066{
1067	struct dmz_target *dmz = ti->private;
1068	unsigned int zone_nr_sectors = dmz_zone_nr_sectors(dmz->metadata);
1069	sector_t capacity;
1070	int i, r;
1071
1072	for (i = 0; i < dmz->nr_ddevs; i++) {
1073		capacity = dmz->dev[i].capacity & ~(zone_nr_sectors - 1);
1074		r = fn(ti, dmz->ddev[i], 0, capacity, data);
1075		if (r)
1076			break;
1077	}
1078	return r;
1079}
1080
1081static void dmz_status(struct dm_target *ti, status_type_t type,
1082		       unsigned int status_flags, char *result,
1083		       unsigned int maxlen)
1084{
1085	struct dmz_target *dmz = ti->private;
1086	ssize_t sz = 0;
1087	char buf[BDEVNAME_SIZE];
1088	struct dmz_dev *dev;
1089	int i;
1090
1091	switch (type) {
1092	case STATUSTYPE_INFO:
1093		DMEMIT("%u zones %u/%u cache",
1094		       dmz_nr_zones(dmz->metadata),
1095		       dmz_nr_unmap_cache_zones(dmz->metadata),
1096		       dmz_nr_cache_zones(dmz->metadata));
1097		for (i = 0; i < dmz->nr_ddevs; i++) {
1098			/*
1099			 * For a multi-device setup the first device
1100			 * contains only cache zones.
1101			 */
1102			if ((i == 0) &&
1103			    (dmz_nr_cache_zones(dmz->metadata) > 0))
1104				continue;
1105			DMEMIT(" %u/%u random %u/%u sequential",
1106			       dmz_nr_unmap_rnd_zones(dmz->metadata, i),
1107			       dmz_nr_rnd_zones(dmz->metadata, i),
1108			       dmz_nr_unmap_seq_zones(dmz->metadata, i),
1109			       dmz_nr_seq_zones(dmz->metadata, i));
1110		}
1111		break;
1112	case STATUSTYPE_TABLE:
1113		dev = &dmz->dev[0];
1114		format_dev_t(buf, dev->bdev->bd_dev);
1115		DMEMIT("%s", buf);
1116		for (i = 1; i < dmz->nr_ddevs; i++) {
1117			dev = &dmz->dev[i];
1118			format_dev_t(buf, dev->bdev->bd_dev);
1119			DMEMIT(" %s", buf);
1120		}
1121		break;
 
 
 
1122	}
1123	return;
1124}
1125
1126static int dmz_message(struct dm_target *ti, unsigned int argc, char **argv,
1127		       char *result, unsigned int maxlen)
1128{
1129	struct dmz_target *dmz = ti->private;
1130	int r = -EINVAL;
1131
1132	if (!strcasecmp(argv[0], "reclaim")) {
1133		int i;
1134
1135		for (i = 0; i < dmz->nr_ddevs; i++)
1136			dmz_schedule_reclaim(dmz->dev[i].reclaim);
1137		r = 0;
1138	} else
1139		DMERR("unrecognized message %s", argv[0]);
1140	return r;
1141}
1142
1143static struct target_type dmz_type = {
1144	.name		 = "zoned",
1145	.version	 = {2, 0, 0},
1146	.features	 = DM_TARGET_SINGLETON | DM_TARGET_ZONED_HM,
1147	.module		 = THIS_MODULE,
1148	.ctr		 = dmz_ctr,
1149	.dtr		 = dmz_dtr,
1150	.map		 = dmz_map,
1151	.io_hints	 = dmz_io_hints,
1152	.prepare_ioctl	 = dmz_prepare_ioctl,
1153	.postsuspend	 = dmz_suspend,
1154	.resume		 = dmz_resume,
1155	.iterate_devices = dmz_iterate_devices,
1156	.status		 = dmz_status,
1157	.message	 = dmz_message,
1158};
1159
1160static int __init dmz_init(void)
1161{
1162	return dm_register_target(&dmz_type);
1163}
1164
1165static void __exit dmz_exit(void)
1166{
1167	dm_unregister_target(&dmz_type);
1168}
1169
1170module_init(dmz_init);
1171module_exit(dmz_exit);
1172
1173MODULE_DESCRIPTION(DM_NAME " target for zoned block devices");
1174MODULE_AUTHOR("Damien Le Moal <damien.lemoal@wdc.com>");
1175MODULE_LICENSE("GPL");