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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#include <linux/crc32.h>
12#include <linux/sched/mm.h>
13
14#define DM_MSG_PREFIX "zoned metadata"
15
16/*
17 * Metadata version.
18 */
19#define DMZ_META_VER 2
20
21/*
22 * On-disk super block magic.
23 */
24#define DMZ_MAGIC ((((unsigned int)('D')) << 24) | \
25 (((unsigned int)('Z')) << 16) | \
26 (((unsigned int)('B')) << 8) | \
27 ((unsigned int)('D')))
28
29/*
30 * On disk super block.
31 * This uses only 512 B but uses on disk a full 4KB block. This block is
32 * followed on disk by the mapping table of chunks to zones and the bitmap
33 * blocks indicating zone block validity.
34 * The overall resulting metadata format is:
35 * (1) Super block (1 block)
36 * (2) Chunk mapping table (nr_map_blocks)
37 * (3) Bitmap blocks (nr_bitmap_blocks)
38 * All metadata blocks are stored in conventional zones, starting from
39 * the first conventional zone found on disk.
40 */
41struct dmz_super {
42 /* Magic number */
43 __le32 magic; /* 4 */
44
45 /* Metadata version number */
46 __le32 version; /* 8 */
47
48 /* Generation number */
49 __le64 gen; /* 16 */
50
51 /* This block number */
52 __le64 sb_block; /* 24 */
53
54 /* The number of metadata blocks, including this super block */
55 __le32 nr_meta_blocks; /* 28 */
56
57 /* The number of sequential zones reserved for reclaim */
58 __le32 nr_reserved_seq; /* 32 */
59
60 /* The number of entries in the mapping table */
61 __le32 nr_chunks; /* 36 */
62
63 /* The number of blocks used for the chunk mapping table */
64 __le32 nr_map_blocks; /* 40 */
65
66 /* The number of blocks used for the block bitmaps */
67 __le32 nr_bitmap_blocks; /* 44 */
68
69 /* Checksum */
70 __le32 crc; /* 48 */
71
72 /* DM-Zoned label */
73 u8 dmz_label[32]; /* 80 */
74
75 /* DM-Zoned UUID */
76 u8 dmz_uuid[16]; /* 96 */
77
78 /* Device UUID */
79 u8 dev_uuid[16]; /* 112 */
80
81 /* Padding to full 512B sector */
82 u8 reserved[400]; /* 512 */
83};
84
85/*
86 * Chunk mapping entry: entries are indexed by chunk number
87 * and give the zone ID (dzone_id) mapping the chunk on disk.
88 * This zone may be sequential or random. If it is a sequential
89 * zone, a second zone (bzone_id) used as a write buffer may
90 * also be specified. This second zone will always be a randomly
91 * writeable zone.
92 */
93struct dmz_map {
94 __le32 dzone_id;
95 __le32 bzone_id;
96};
97
98/*
99 * Chunk mapping table metadata: 512 8-bytes entries per 4KB block.
100 */
101#define DMZ_MAP_ENTRIES (DMZ_BLOCK_SIZE / sizeof(struct dmz_map))
102#define DMZ_MAP_ENTRIES_SHIFT (ilog2(DMZ_MAP_ENTRIES))
103#define DMZ_MAP_ENTRIES_MASK (DMZ_MAP_ENTRIES - 1)
104#define DMZ_MAP_UNMAPPED UINT_MAX
105
106/*
107 * Meta data block descriptor (for cached metadata blocks).
108 */
109struct dmz_mblock {
110 struct rb_node node;
111 struct list_head link;
112 sector_t no;
113 unsigned int ref;
114 unsigned long state;
115 struct page *page;
116 void *data;
117};
118
119/*
120 * Metadata block state flags.
121 */
122enum {
123 DMZ_META_DIRTY,
124 DMZ_META_READING,
125 DMZ_META_WRITING,
126 DMZ_META_ERROR,
127};
128
129/*
130 * Super block information (one per metadata set).
131 */
132struct dmz_sb {
133 sector_t block;
134 struct dmz_dev *dev;
135 struct dmz_mblock *mblk;
136 struct dmz_super *sb;
137 struct dm_zone *zone;
138};
139
140/*
141 * In-memory metadata.
142 */
143struct dmz_metadata {
144 struct dmz_dev *dev;
145 unsigned int nr_devs;
146
147 char devname[BDEVNAME_SIZE];
148 char label[BDEVNAME_SIZE];
149 uuid_t uuid;
150
151 sector_t zone_bitmap_size;
152 unsigned int zone_nr_bitmap_blocks;
153 unsigned int zone_bits_per_mblk;
154
155 sector_t zone_nr_blocks;
156 sector_t zone_nr_blocks_shift;
157
158 sector_t zone_nr_sectors;
159 sector_t zone_nr_sectors_shift;
160
161 unsigned int nr_bitmap_blocks;
162 unsigned int nr_map_blocks;
163
164 unsigned int nr_zones;
165 unsigned int nr_useable_zones;
166 unsigned int nr_meta_blocks;
167 unsigned int nr_meta_zones;
168 unsigned int nr_data_zones;
169 unsigned int nr_cache_zones;
170 unsigned int nr_rnd_zones;
171 unsigned int nr_reserved_seq;
172 unsigned int nr_chunks;
173
174 /* Zone information array */
175 struct xarray zones;
176
177 struct dmz_sb sb[2];
178 unsigned int mblk_primary;
179 unsigned int sb_version;
180 u64 sb_gen;
181 unsigned int min_nr_mblks;
182 unsigned int max_nr_mblks;
183 atomic_t nr_mblks;
184 struct rw_semaphore mblk_sem;
185 struct mutex mblk_flush_lock;
186 spinlock_t mblk_lock;
187 struct rb_root mblk_rbtree;
188 struct list_head mblk_lru_list;
189 struct list_head mblk_dirty_list;
190 struct shrinker mblk_shrinker;
191
192 /* Zone allocation management */
193 struct mutex map_lock;
194 struct dmz_mblock **map_mblk;
195
196 unsigned int nr_cache;
197 atomic_t unmap_nr_cache;
198 struct list_head unmap_cache_list;
199 struct list_head map_cache_list;
200
201 atomic_t nr_reserved_seq_zones;
202 struct list_head reserved_seq_zones_list;
203
204 wait_queue_head_t free_wq;
205};
206
207#define dmz_zmd_info(zmd, format, args...) \
208 DMINFO("(%s): " format, (zmd)->label, ## args)
209
210#define dmz_zmd_err(zmd, format, args...) \
211 DMERR("(%s): " format, (zmd)->label, ## args)
212
213#define dmz_zmd_warn(zmd, format, args...) \
214 DMWARN("(%s): " format, (zmd)->label, ## args)
215
216#define dmz_zmd_debug(zmd, format, args...) \
217 DMDEBUG("(%s): " format, (zmd)->label, ## args)
218/*
219 * Various accessors
220 */
221static unsigned int dmz_dev_zone_id(struct dmz_metadata *zmd, struct dm_zone *zone)
222{
223 if (WARN_ON(!zone))
224 return 0;
225
226 return zone->id - zone->dev->zone_offset;
227}
228
229sector_t dmz_start_sect(struct dmz_metadata *zmd, struct dm_zone *zone)
230{
231 unsigned int zone_id = dmz_dev_zone_id(zmd, zone);
232
233 return (sector_t)zone_id << zmd->zone_nr_sectors_shift;
234}
235
236sector_t dmz_start_block(struct dmz_metadata *zmd, struct dm_zone *zone)
237{
238 unsigned int zone_id = dmz_dev_zone_id(zmd, zone);
239
240 return (sector_t)zone_id << zmd->zone_nr_blocks_shift;
241}
242
243unsigned int dmz_zone_nr_blocks(struct dmz_metadata *zmd)
244{
245 return zmd->zone_nr_blocks;
246}
247
248unsigned int dmz_zone_nr_blocks_shift(struct dmz_metadata *zmd)
249{
250 return zmd->zone_nr_blocks_shift;
251}
252
253unsigned int dmz_zone_nr_sectors(struct dmz_metadata *zmd)
254{
255 return zmd->zone_nr_sectors;
256}
257
258unsigned int dmz_zone_nr_sectors_shift(struct dmz_metadata *zmd)
259{
260 return zmd->zone_nr_sectors_shift;
261}
262
263unsigned int dmz_nr_zones(struct dmz_metadata *zmd)
264{
265 return zmd->nr_zones;
266}
267
268unsigned int dmz_nr_chunks(struct dmz_metadata *zmd)
269{
270 return zmd->nr_chunks;
271}
272
273unsigned int dmz_nr_rnd_zones(struct dmz_metadata *zmd, int idx)
274{
275 return zmd->dev[idx].nr_rnd;
276}
277
278unsigned int dmz_nr_unmap_rnd_zones(struct dmz_metadata *zmd, int idx)
279{
280 return atomic_read(&zmd->dev[idx].unmap_nr_rnd);
281}
282
283unsigned int dmz_nr_cache_zones(struct dmz_metadata *zmd)
284{
285 return zmd->nr_cache;
286}
287
288unsigned int dmz_nr_unmap_cache_zones(struct dmz_metadata *zmd)
289{
290 return atomic_read(&zmd->unmap_nr_cache);
291}
292
293unsigned int dmz_nr_seq_zones(struct dmz_metadata *zmd, int idx)
294{
295 return zmd->dev[idx].nr_seq;
296}
297
298unsigned int dmz_nr_unmap_seq_zones(struct dmz_metadata *zmd, int idx)
299{
300 return atomic_read(&zmd->dev[idx].unmap_nr_seq);
301}
302
303static struct dm_zone *dmz_get(struct dmz_metadata *zmd, unsigned int zone_id)
304{
305 return xa_load(&zmd->zones, zone_id);
306}
307
308static struct dm_zone *dmz_insert(struct dmz_metadata *zmd,
309 unsigned int zone_id, struct dmz_dev *dev)
310{
311 struct dm_zone *zone = kzalloc(sizeof(struct dm_zone), GFP_KERNEL);
312
313 if (!zone)
314 return ERR_PTR(-ENOMEM);
315
316 if (xa_insert(&zmd->zones, zone_id, zone, GFP_KERNEL)) {
317 kfree(zone);
318 return ERR_PTR(-EBUSY);
319 }
320
321 INIT_LIST_HEAD(&zone->link);
322 atomic_set(&zone->refcount, 0);
323 zone->id = zone_id;
324 zone->chunk = DMZ_MAP_UNMAPPED;
325 zone->dev = dev;
326
327 return zone;
328}
329
330const char *dmz_metadata_label(struct dmz_metadata *zmd)
331{
332 return (const char *)zmd->label;
333}
334
335bool dmz_check_dev(struct dmz_metadata *zmd)
336{
337 unsigned int i;
338
339 for (i = 0; i < zmd->nr_devs; i++) {
340 if (!dmz_check_bdev(&zmd->dev[i]))
341 return false;
342 }
343 return true;
344}
345
346bool dmz_dev_is_dying(struct dmz_metadata *zmd)
347{
348 unsigned int i;
349
350 for (i = 0; i < zmd->nr_devs; i++) {
351 if (dmz_bdev_is_dying(&zmd->dev[i]))
352 return true;
353 }
354 return false;
355}
356
357/*
358 * Lock/unlock mapping table.
359 * The map lock also protects all the zone lists.
360 */
361void dmz_lock_map(struct dmz_metadata *zmd)
362{
363 mutex_lock(&zmd->map_lock);
364}
365
366void dmz_unlock_map(struct dmz_metadata *zmd)
367{
368 mutex_unlock(&zmd->map_lock);
369}
370
371/*
372 * Lock/unlock metadata access. This is a "read" lock on a semaphore
373 * that prevents metadata flush from running while metadata are being
374 * modified. The actual metadata write mutual exclusion is achieved with
375 * the map lock and zone state management (active and reclaim state are
376 * mutually exclusive).
377 */
378void dmz_lock_metadata(struct dmz_metadata *zmd)
379{
380 down_read(&zmd->mblk_sem);
381}
382
383void dmz_unlock_metadata(struct dmz_metadata *zmd)
384{
385 up_read(&zmd->mblk_sem);
386}
387
388/*
389 * Lock/unlock flush: prevent concurrent executions
390 * of dmz_flush_metadata as well as metadata modification in reclaim
391 * while flush is being executed.
392 */
393void dmz_lock_flush(struct dmz_metadata *zmd)
394{
395 mutex_lock(&zmd->mblk_flush_lock);
396}
397
398void dmz_unlock_flush(struct dmz_metadata *zmd)
399{
400 mutex_unlock(&zmd->mblk_flush_lock);
401}
402
403/*
404 * Allocate a metadata block.
405 */
406static struct dmz_mblock *dmz_alloc_mblock(struct dmz_metadata *zmd,
407 sector_t mblk_no)
408{
409 struct dmz_mblock *mblk = NULL;
410
411 /* See if we can reuse cached blocks */
412 if (zmd->max_nr_mblks && atomic_read(&zmd->nr_mblks) > zmd->max_nr_mblks) {
413 spin_lock(&zmd->mblk_lock);
414 mblk = list_first_entry_or_null(&zmd->mblk_lru_list,
415 struct dmz_mblock, link);
416 if (mblk) {
417 list_del_init(&mblk->link);
418 rb_erase(&mblk->node, &zmd->mblk_rbtree);
419 mblk->no = mblk_no;
420 }
421 spin_unlock(&zmd->mblk_lock);
422 if (mblk)
423 return mblk;
424 }
425
426 /* Allocate a new block */
427 mblk = kmalloc(sizeof(struct dmz_mblock), GFP_NOIO);
428 if (!mblk)
429 return NULL;
430
431 mblk->page = alloc_page(GFP_NOIO);
432 if (!mblk->page) {
433 kfree(mblk);
434 return NULL;
435 }
436
437 RB_CLEAR_NODE(&mblk->node);
438 INIT_LIST_HEAD(&mblk->link);
439 mblk->ref = 0;
440 mblk->state = 0;
441 mblk->no = mblk_no;
442 mblk->data = page_address(mblk->page);
443
444 atomic_inc(&zmd->nr_mblks);
445
446 return mblk;
447}
448
449/*
450 * Free a metadata block.
451 */
452static void dmz_free_mblock(struct dmz_metadata *zmd, struct dmz_mblock *mblk)
453{
454 __free_pages(mblk->page, 0);
455 kfree(mblk);
456
457 atomic_dec(&zmd->nr_mblks);
458}
459
460/*
461 * Insert a metadata block in the rbtree.
462 */
463static void dmz_insert_mblock(struct dmz_metadata *zmd, struct dmz_mblock *mblk)
464{
465 struct rb_root *root = &zmd->mblk_rbtree;
466 struct rb_node **new = &(root->rb_node), *parent = NULL;
467 struct dmz_mblock *b;
468
469 /* Figure out where to put the new node */
470 while (*new) {
471 b = container_of(*new, struct dmz_mblock, node);
472 parent = *new;
473 new = (b->no < mblk->no) ? &((*new)->rb_left) : &((*new)->rb_right);
474 }
475
476 /* Add new node and rebalance tree */
477 rb_link_node(&mblk->node, parent, new);
478 rb_insert_color(&mblk->node, root);
479}
480
481/*
482 * Lookup a metadata block in the rbtree. If the block is found, increment
483 * its reference count.
484 */
485static struct dmz_mblock *dmz_get_mblock_fast(struct dmz_metadata *zmd,
486 sector_t mblk_no)
487{
488 struct rb_root *root = &zmd->mblk_rbtree;
489 struct rb_node *node = root->rb_node;
490 struct dmz_mblock *mblk;
491
492 while (node) {
493 mblk = container_of(node, struct dmz_mblock, node);
494 if (mblk->no == mblk_no) {
495 /*
496 * If this is the first reference to the block,
497 * remove it from the LRU list.
498 */
499 mblk->ref++;
500 if (mblk->ref == 1 &&
501 !test_bit(DMZ_META_DIRTY, &mblk->state))
502 list_del_init(&mblk->link);
503 return mblk;
504 }
505 node = (mblk->no < mblk_no) ? node->rb_left : node->rb_right;
506 }
507
508 return NULL;
509}
510
511/*
512 * Metadata block BIO end callback.
513 */
514static void dmz_mblock_bio_end_io(struct bio *bio)
515{
516 struct dmz_mblock *mblk = bio->bi_private;
517 int flag;
518
519 if (bio->bi_status)
520 set_bit(DMZ_META_ERROR, &mblk->state);
521
522 if (bio_op(bio) == REQ_OP_WRITE)
523 flag = DMZ_META_WRITING;
524 else
525 flag = DMZ_META_READING;
526
527 clear_bit_unlock(flag, &mblk->state);
528 smp_mb__after_atomic();
529 wake_up_bit(&mblk->state, flag);
530
531 bio_put(bio);
532}
533
534/*
535 * Read an uncached metadata block from disk and add it to the cache.
536 */
537static struct dmz_mblock *dmz_get_mblock_slow(struct dmz_metadata *zmd,
538 sector_t mblk_no)
539{
540 struct dmz_mblock *mblk, *m;
541 sector_t block = zmd->sb[zmd->mblk_primary].block + mblk_no;
542 struct dmz_dev *dev = zmd->sb[zmd->mblk_primary].dev;
543 struct bio *bio;
544
545 if (dmz_bdev_is_dying(dev))
546 return ERR_PTR(-EIO);
547
548 /* Get a new block and a BIO to read it */
549 mblk = dmz_alloc_mblock(zmd, mblk_no);
550 if (!mblk)
551 return ERR_PTR(-ENOMEM);
552
553 bio = bio_alloc(GFP_NOIO, 1);
554 if (!bio) {
555 dmz_free_mblock(zmd, mblk);
556 return ERR_PTR(-ENOMEM);
557 }
558
559 spin_lock(&zmd->mblk_lock);
560
561 /*
562 * Make sure that another context did not start reading
563 * the block already.
564 */
565 m = dmz_get_mblock_fast(zmd, mblk_no);
566 if (m) {
567 spin_unlock(&zmd->mblk_lock);
568 dmz_free_mblock(zmd, mblk);
569 bio_put(bio);
570 return m;
571 }
572
573 mblk->ref++;
574 set_bit(DMZ_META_READING, &mblk->state);
575 dmz_insert_mblock(zmd, mblk);
576
577 spin_unlock(&zmd->mblk_lock);
578
579 /* Submit read BIO */
580 bio->bi_iter.bi_sector = dmz_blk2sect(block);
581 bio_set_dev(bio, dev->bdev);
582 bio->bi_private = mblk;
583 bio->bi_end_io = dmz_mblock_bio_end_io;
584 bio_set_op_attrs(bio, REQ_OP_READ, REQ_META | REQ_PRIO);
585 bio_add_page(bio, mblk->page, DMZ_BLOCK_SIZE, 0);
586 submit_bio(bio);
587
588 return mblk;
589}
590
591/*
592 * Free metadata blocks.
593 */
594static unsigned long dmz_shrink_mblock_cache(struct dmz_metadata *zmd,
595 unsigned long limit)
596{
597 struct dmz_mblock *mblk;
598 unsigned long count = 0;
599
600 if (!zmd->max_nr_mblks)
601 return 0;
602
603 while (!list_empty(&zmd->mblk_lru_list) &&
604 atomic_read(&zmd->nr_mblks) > zmd->min_nr_mblks &&
605 count < limit) {
606 mblk = list_first_entry(&zmd->mblk_lru_list,
607 struct dmz_mblock, link);
608 list_del_init(&mblk->link);
609 rb_erase(&mblk->node, &zmd->mblk_rbtree);
610 dmz_free_mblock(zmd, mblk);
611 count++;
612 }
613
614 return count;
615}
616
617/*
618 * For mblock shrinker: get the number of unused metadata blocks in the cache.
619 */
620static unsigned long dmz_mblock_shrinker_count(struct shrinker *shrink,
621 struct shrink_control *sc)
622{
623 struct dmz_metadata *zmd = container_of(shrink, struct dmz_metadata, mblk_shrinker);
624
625 return atomic_read(&zmd->nr_mblks);
626}
627
628/*
629 * For mblock shrinker: scan unused metadata blocks and shrink the cache.
630 */
631static unsigned long dmz_mblock_shrinker_scan(struct shrinker *shrink,
632 struct shrink_control *sc)
633{
634 struct dmz_metadata *zmd = container_of(shrink, struct dmz_metadata, mblk_shrinker);
635 unsigned long count;
636
637 spin_lock(&zmd->mblk_lock);
638 count = dmz_shrink_mblock_cache(zmd, sc->nr_to_scan);
639 spin_unlock(&zmd->mblk_lock);
640
641 return count ? count : SHRINK_STOP;
642}
643
644/*
645 * Release a metadata block.
646 */
647static void dmz_release_mblock(struct dmz_metadata *zmd,
648 struct dmz_mblock *mblk)
649{
650
651 if (!mblk)
652 return;
653
654 spin_lock(&zmd->mblk_lock);
655
656 mblk->ref--;
657 if (mblk->ref == 0) {
658 if (test_bit(DMZ_META_ERROR, &mblk->state)) {
659 rb_erase(&mblk->node, &zmd->mblk_rbtree);
660 dmz_free_mblock(zmd, mblk);
661 } else if (!test_bit(DMZ_META_DIRTY, &mblk->state)) {
662 list_add_tail(&mblk->link, &zmd->mblk_lru_list);
663 dmz_shrink_mblock_cache(zmd, 1);
664 }
665 }
666
667 spin_unlock(&zmd->mblk_lock);
668}
669
670/*
671 * Get a metadata block from the rbtree. If the block
672 * is not present, read it from disk.
673 */
674static struct dmz_mblock *dmz_get_mblock(struct dmz_metadata *zmd,
675 sector_t mblk_no)
676{
677 struct dmz_mblock *mblk;
678 struct dmz_dev *dev = zmd->sb[zmd->mblk_primary].dev;
679
680 /* Check rbtree */
681 spin_lock(&zmd->mblk_lock);
682 mblk = dmz_get_mblock_fast(zmd, mblk_no);
683 spin_unlock(&zmd->mblk_lock);
684
685 if (!mblk) {
686 /* Cache miss: read the block from disk */
687 mblk = dmz_get_mblock_slow(zmd, mblk_no);
688 if (IS_ERR(mblk))
689 return mblk;
690 }
691
692 /* Wait for on-going read I/O and check for error */
693 wait_on_bit_io(&mblk->state, DMZ_META_READING,
694 TASK_UNINTERRUPTIBLE);
695 if (test_bit(DMZ_META_ERROR, &mblk->state)) {
696 dmz_release_mblock(zmd, mblk);
697 dmz_check_bdev(dev);
698 return ERR_PTR(-EIO);
699 }
700
701 return mblk;
702}
703
704/*
705 * Mark a metadata block dirty.
706 */
707static void dmz_dirty_mblock(struct dmz_metadata *zmd, struct dmz_mblock *mblk)
708{
709 spin_lock(&zmd->mblk_lock);
710 if (!test_and_set_bit(DMZ_META_DIRTY, &mblk->state))
711 list_add_tail(&mblk->link, &zmd->mblk_dirty_list);
712 spin_unlock(&zmd->mblk_lock);
713}
714
715/*
716 * Issue a metadata block write BIO.
717 */
718static int dmz_write_mblock(struct dmz_metadata *zmd, struct dmz_mblock *mblk,
719 unsigned int set)
720{
721 struct dmz_dev *dev = zmd->sb[set].dev;
722 sector_t block = zmd->sb[set].block + mblk->no;
723 struct bio *bio;
724
725 if (dmz_bdev_is_dying(dev))
726 return -EIO;
727
728 bio = bio_alloc(GFP_NOIO, 1);
729 if (!bio) {
730 set_bit(DMZ_META_ERROR, &mblk->state);
731 return -ENOMEM;
732 }
733
734 set_bit(DMZ_META_WRITING, &mblk->state);
735
736 bio->bi_iter.bi_sector = dmz_blk2sect(block);
737 bio_set_dev(bio, dev->bdev);
738 bio->bi_private = mblk;
739 bio->bi_end_io = dmz_mblock_bio_end_io;
740 bio_set_op_attrs(bio, REQ_OP_WRITE, REQ_META | REQ_PRIO);
741 bio_add_page(bio, mblk->page, DMZ_BLOCK_SIZE, 0);
742 submit_bio(bio);
743
744 return 0;
745}
746
747/*
748 * Read/write a metadata block.
749 */
750static int dmz_rdwr_block(struct dmz_dev *dev, int op,
751 sector_t block, struct page *page)
752{
753 struct bio *bio;
754 int ret;
755
756 if (WARN_ON(!dev))
757 return -EIO;
758
759 if (dmz_bdev_is_dying(dev))
760 return -EIO;
761
762 bio = bio_alloc(GFP_NOIO, 1);
763 if (!bio)
764 return -ENOMEM;
765
766 bio->bi_iter.bi_sector = dmz_blk2sect(block);
767 bio_set_dev(bio, dev->bdev);
768 bio_set_op_attrs(bio, op, REQ_SYNC | REQ_META | REQ_PRIO);
769 bio_add_page(bio, page, DMZ_BLOCK_SIZE, 0);
770 ret = submit_bio_wait(bio);
771 bio_put(bio);
772
773 if (ret)
774 dmz_check_bdev(dev);
775 return ret;
776}
777
778/*
779 * Write super block of the specified metadata set.
780 */
781static int dmz_write_sb(struct dmz_metadata *zmd, unsigned int set)
782{
783 struct dmz_mblock *mblk = zmd->sb[set].mblk;
784 struct dmz_super *sb = zmd->sb[set].sb;
785 struct dmz_dev *dev = zmd->sb[set].dev;
786 sector_t sb_block;
787 u64 sb_gen = zmd->sb_gen + 1;
788 int ret;
789
790 sb->magic = cpu_to_le32(DMZ_MAGIC);
791
792 sb->version = cpu_to_le32(zmd->sb_version);
793 if (zmd->sb_version > 1) {
794 BUILD_BUG_ON(UUID_SIZE != 16);
795 export_uuid(sb->dmz_uuid, &zmd->uuid);
796 memcpy(sb->dmz_label, zmd->label, BDEVNAME_SIZE);
797 export_uuid(sb->dev_uuid, &dev->uuid);
798 }
799
800 sb->gen = cpu_to_le64(sb_gen);
801
802 /*
803 * The metadata always references the absolute block address,
804 * ie relative to the entire block range, not the per-device
805 * block address.
806 */
807 sb_block = zmd->sb[set].zone->id << zmd->zone_nr_blocks_shift;
808 sb->sb_block = cpu_to_le64(sb_block);
809 sb->nr_meta_blocks = cpu_to_le32(zmd->nr_meta_blocks);
810 sb->nr_reserved_seq = cpu_to_le32(zmd->nr_reserved_seq);
811 sb->nr_chunks = cpu_to_le32(zmd->nr_chunks);
812
813 sb->nr_map_blocks = cpu_to_le32(zmd->nr_map_blocks);
814 sb->nr_bitmap_blocks = cpu_to_le32(zmd->nr_bitmap_blocks);
815
816 sb->crc = 0;
817 sb->crc = cpu_to_le32(crc32_le(sb_gen, (unsigned char *)sb, DMZ_BLOCK_SIZE));
818
819 ret = dmz_rdwr_block(dev, REQ_OP_WRITE, zmd->sb[set].block,
820 mblk->page);
821 if (ret == 0)
822 ret = blkdev_issue_flush(dev->bdev, GFP_NOIO);
823
824 return ret;
825}
826
827/*
828 * Write dirty metadata blocks to the specified set.
829 */
830static int dmz_write_dirty_mblocks(struct dmz_metadata *zmd,
831 struct list_head *write_list,
832 unsigned int set)
833{
834 struct dmz_mblock *mblk;
835 struct dmz_dev *dev = zmd->sb[set].dev;
836 struct blk_plug plug;
837 int ret = 0, nr_mblks_submitted = 0;
838
839 /* Issue writes */
840 blk_start_plug(&plug);
841 list_for_each_entry(mblk, write_list, link) {
842 ret = dmz_write_mblock(zmd, mblk, set);
843 if (ret)
844 break;
845 nr_mblks_submitted++;
846 }
847 blk_finish_plug(&plug);
848
849 /* Wait for completion */
850 list_for_each_entry(mblk, write_list, link) {
851 if (!nr_mblks_submitted)
852 break;
853 wait_on_bit_io(&mblk->state, DMZ_META_WRITING,
854 TASK_UNINTERRUPTIBLE);
855 if (test_bit(DMZ_META_ERROR, &mblk->state)) {
856 clear_bit(DMZ_META_ERROR, &mblk->state);
857 dmz_check_bdev(dev);
858 ret = -EIO;
859 }
860 nr_mblks_submitted--;
861 }
862
863 /* Flush drive cache (this will also sync data) */
864 if (ret == 0)
865 ret = blkdev_issue_flush(dev->bdev, GFP_NOIO);
866
867 return ret;
868}
869
870/*
871 * Log dirty metadata blocks.
872 */
873static int dmz_log_dirty_mblocks(struct dmz_metadata *zmd,
874 struct list_head *write_list)
875{
876 unsigned int log_set = zmd->mblk_primary ^ 0x1;
877 int ret;
878
879 /* Write dirty blocks to the log */
880 ret = dmz_write_dirty_mblocks(zmd, write_list, log_set);
881 if (ret)
882 return ret;
883
884 /*
885 * No error so far: now validate the log by updating the
886 * log index super block generation.
887 */
888 ret = dmz_write_sb(zmd, log_set);
889 if (ret)
890 return ret;
891
892 return 0;
893}
894
895/*
896 * Flush dirty metadata blocks.
897 */
898int dmz_flush_metadata(struct dmz_metadata *zmd)
899{
900 struct dmz_mblock *mblk;
901 struct list_head write_list;
902 struct dmz_dev *dev;
903 int ret;
904
905 if (WARN_ON(!zmd))
906 return 0;
907
908 INIT_LIST_HEAD(&write_list);
909
910 /*
911 * Make sure that metadata blocks are stable before logging: take
912 * the write lock on the metadata semaphore to prevent target BIOs
913 * from modifying metadata.
914 */
915 down_write(&zmd->mblk_sem);
916 dev = zmd->sb[zmd->mblk_primary].dev;
917
918 /*
919 * This is called from the target flush work and reclaim work.
920 * Concurrent execution is not allowed.
921 */
922 dmz_lock_flush(zmd);
923
924 if (dmz_bdev_is_dying(dev)) {
925 ret = -EIO;
926 goto out;
927 }
928
929 /* Get dirty blocks */
930 spin_lock(&zmd->mblk_lock);
931 list_splice_init(&zmd->mblk_dirty_list, &write_list);
932 spin_unlock(&zmd->mblk_lock);
933
934 /* If there are no dirty metadata blocks, just flush the device cache */
935 if (list_empty(&write_list)) {
936 ret = blkdev_issue_flush(dev->bdev, GFP_NOIO);
937 goto err;
938 }
939
940 /*
941 * The primary metadata set is still clean. Keep it this way until
942 * all updates are successful in the secondary set. That is, use
943 * the secondary set as a log.
944 */
945 ret = dmz_log_dirty_mblocks(zmd, &write_list);
946 if (ret)
947 goto err;
948
949 /*
950 * The log is on disk. It is now safe to update in place
951 * in the primary metadata set.
952 */
953 ret = dmz_write_dirty_mblocks(zmd, &write_list, zmd->mblk_primary);
954 if (ret)
955 goto err;
956
957 ret = dmz_write_sb(zmd, zmd->mblk_primary);
958 if (ret)
959 goto err;
960
961 while (!list_empty(&write_list)) {
962 mblk = list_first_entry(&write_list, struct dmz_mblock, link);
963 list_del_init(&mblk->link);
964
965 spin_lock(&zmd->mblk_lock);
966 clear_bit(DMZ_META_DIRTY, &mblk->state);
967 if (mblk->ref == 0)
968 list_add_tail(&mblk->link, &zmd->mblk_lru_list);
969 spin_unlock(&zmd->mblk_lock);
970 }
971
972 zmd->sb_gen++;
973out:
974 dmz_unlock_flush(zmd);
975 up_write(&zmd->mblk_sem);
976
977 return ret;
978
979err:
980 if (!list_empty(&write_list)) {
981 spin_lock(&zmd->mblk_lock);
982 list_splice(&write_list, &zmd->mblk_dirty_list);
983 spin_unlock(&zmd->mblk_lock);
984 }
985 if (!dmz_check_bdev(dev))
986 ret = -EIO;
987 goto out;
988}
989
990/*
991 * Check super block.
992 */
993static int dmz_check_sb(struct dmz_metadata *zmd, struct dmz_sb *dsb,
994 bool tertiary)
995{
996 struct dmz_super *sb = dsb->sb;
997 struct dmz_dev *dev = dsb->dev;
998 unsigned int nr_meta_zones, nr_data_zones;
999 u32 crc, stored_crc;
1000 u64 gen, sb_block;
1001
1002 if (le32_to_cpu(sb->magic) != DMZ_MAGIC) {
1003 dmz_dev_err(dev, "Invalid meta magic (needed 0x%08x, got 0x%08x)",
1004 DMZ_MAGIC, le32_to_cpu(sb->magic));
1005 return -ENXIO;
1006 }
1007
1008 zmd->sb_version = le32_to_cpu(sb->version);
1009 if (zmd->sb_version > DMZ_META_VER) {
1010 dmz_dev_err(dev, "Invalid meta version (needed %d, got %d)",
1011 DMZ_META_VER, zmd->sb_version);
1012 return -EINVAL;
1013 }
1014 if (zmd->sb_version < 2 && tertiary) {
1015 dmz_dev_err(dev, "Tertiary superblocks are not supported");
1016 return -EINVAL;
1017 }
1018
1019 gen = le64_to_cpu(sb->gen);
1020 stored_crc = le32_to_cpu(sb->crc);
1021 sb->crc = 0;
1022 crc = crc32_le(gen, (unsigned char *)sb, DMZ_BLOCK_SIZE);
1023 if (crc != stored_crc) {
1024 dmz_dev_err(dev, "Invalid checksum (needed 0x%08x, got 0x%08x)",
1025 crc, stored_crc);
1026 return -ENXIO;
1027 }
1028
1029 sb_block = le64_to_cpu(sb->sb_block);
1030 if (sb_block != (u64)dsb->zone->id << zmd->zone_nr_blocks_shift ) {
1031 dmz_dev_err(dev, "Invalid superblock position "
1032 "(is %llu expected %llu)",
1033 sb_block,
1034 (u64)dsb->zone->id << zmd->zone_nr_blocks_shift);
1035 return -EINVAL;
1036 }
1037 if (zmd->sb_version > 1) {
1038 uuid_t sb_uuid;
1039
1040 import_uuid(&sb_uuid, sb->dmz_uuid);
1041 if (uuid_is_null(&sb_uuid)) {
1042 dmz_dev_err(dev, "NULL DM-Zoned uuid");
1043 return -ENXIO;
1044 } else if (uuid_is_null(&zmd->uuid)) {
1045 uuid_copy(&zmd->uuid, &sb_uuid);
1046 } else if (!uuid_equal(&zmd->uuid, &sb_uuid)) {
1047 dmz_dev_err(dev, "mismatching DM-Zoned uuid, "
1048 "is %pUl expected %pUl",
1049 &sb_uuid, &zmd->uuid);
1050 return -ENXIO;
1051 }
1052 if (!strlen(zmd->label))
1053 memcpy(zmd->label, sb->dmz_label, BDEVNAME_SIZE);
1054 else if (memcmp(zmd->label, sb->dmz_label, BDEVNAME_SIZE)) {
1055 dmz_dev_err(dev, "mismatching DM-Zoned label, "
1056 "is %s expected %s",
1057 sb->dmz_label, zmd->label);
1058 return -ENXIO;
1059 }
1060 import_uuid(&dev->uuid, sb->dev_uuid);
1061 if (uuid_is_null(&dev->uuid)) {
1062 dmz_dev_err(dev, "NULL device uuid");
1063 return -ENXIO;
1064 }
1065
1066 if (tertiary) {
1067 /*
1068 * Generation number should be 0, but it doesn't
1069 * really matter if it isn't.
1070 */
1071 if (gen != 0)
1072 dmz_dev_warn(dev, "Invalid generation %llu",
1073 gen);
1074 return 0;
1075 }
1076 }
1077
1078 nr_meta_zones = (le32_to_cpu(sb->nr_meta_blocks) + zmd->zone_nr_blocks - 1)
1079 >> zmd->zone_nr_blocks_shift;
1080 if (!nr_meta_zones ||
1081 (zmd->nr_devs <= 1 && nr_meta_zones >= zmd->nr_rnd_zones) ||
1082 (zmd->nr_devs > 1 && nr_meta_zones >= zmd->nr_cache_zones)) {
1083 dmz_dev_err(dev, "Invalid number of metadata blocks");
1084 return -ENXIO;
1085 }
1086
1087 if (!le32_to_cpu(sb->nr_reserved_seq) ||
1088 le32_to_cpu(sb->nr_reserved_seq) >= (zmd->nr_useable_zones - nr_meta_zones)) {
1089 dmz_dev_err(dev, "Invalid number of reserved sequential zones");
1090 return -ENXIO;
1091 }
1092
1093 nr_data_zones = zmd->nr_useable_zones -
1094 (nr_meta_zones * 2 + le32_to_cpu(sb->nr_reserved_seq));
1095 if (le32_to_cpu(sb->nr_chunks) > nr_data_zones) {
1096 dmz_dev_err(dev, "Invalid number of chunks %u / %u",
1097 le32_to_cpu(sb->nr_chunks), nr_data_zones);
1098 return -ENXIO;
1099 }
1100
1101 /* OK */
1102 zmd->nr_meta_blocks = le32_to_cpu(sb->nr_meta_blocks);
1103 zmd->nr_reserved_seq = le32_to_cpu(sb->nr_reserved_seq);
1104 zmd->nr_chunks = le32_to_cpu(sb->nr_chunks);
1105 zmd->nr_map_blocks = le32_to_cpu(sb->nr_map_blocks);
1106 zmd->nr_bitmap_blocks = le32_to_cpu(sb->nr_bitmap_blocks);
1107 zmd->nr_meta_zones = nr_meta_zones;
1108 zmd->nr_data_zones = nr_data_zones;
1109
1110 return 0;
1111}
1112
1113/*
1114 * Read the first or second super block from disk.
1115 */
1116static int dmz_read_sb(struct dmz_metadata *zmd, struct dmz_sb *sb, int set)
1117{
1118 dmz_zmd_debug(zmd, "read superblock set %d dev %s block %llu",
1119 set, sb->dev->name, sb->block);
1120
1121 return dmz_rdwr_block(sb->dev, REQ_OP_READ,
1122 sb->block, sb->mblk->page);
1123}
1124
1125/*
1126 * Determine the position of the secondary super blocks on disk.
1127 * This is used only if a corruption of the primary super block
1128 * is detected.
1129 */
1130static int dmz_lookup_secondary_sb(struct dmz_metadata *zmd)
1131{
1132 unsigned int zone_nr_blocks = zmd->zone_nr_blocks;
1133 struct dmz_mblock *mblk;
1134 unsigned int zone_id = zmd->sb[0].zone->id;
1135 int i;
1136
1137 /* Allocate a block */
1138 mblk = dmz_alloc_mblock(zmd, 0);
1139 if (!mblk)
1140 return -ENOMEM;
1141
1142 zmd->sb[1].mblk = mblk;
1143 zmd->sb[1].sb = mblk->data;
1144
1145 /* Bad first super block: search for the second one */
1146 zmd->sb[1].block = zmd->sb[0].block + zone_nr_blocks;
1147 zmd->sb[1].zone = dmz_get(zmd, zone_id + 1);
1148 zmd->sb[1].dev = zmd->sb[0].dev;
1149 for (i = 1; i < zmd->nr_rnd_zones; i++) {
1150 if (dmz_read_sb(zmd, &zmd->sb[1], 1) != 0)
1151 break;
1152 if (le32_to_cpu(zmd->sb[1].sb->magic) == DMZ_MAGIC)
1153 return 0;
1154 zmd->sb[1].block += zone_nr_blocks;
1155 zmd->sb[1].zone = dmz_get(zmd, zone_id + i);
1156 }
1157
1158 dmz_free_mblock(zmd, mblk);
1159 zmd->sb[1].mblk = NULL;
1160 zmd->sb[1].zone = NULL;
1161 zmd->sb[1].dev = NULL;
1162
1163 return -EIO;
1164}
1165
1166/*
1167 * Read a super block from disk.
1168 */
1169static int dmz_get_sb(struct dmz_metadata *zmd, struct dmz_sb *sb, int set)
1170{
1171 struct dmz_mblock *mblk;
1172 int ret;
1173
1174 /* Allocate a block */
1175 mblk = dmz_alloc_mblock(zmd, 0);
1176 if (!mblk)
1177 return -ENOMEM;
1178
1179 sb->mblk = mblk;
1180 sb->sb = mblk->data;
1181
1182 /* Read super block */
1183 ret = dmz_read_sb(zmd, sb, set);
1184 if (ret) {
1185 dmz_free_mblock(zmd, mblk);
1186 sb->mblk = NULL;
1187 return ret;
1188 }
1189
1190 return 0;
1191}
1192
1193/*
1194 * Recover a metadata set.
1195 */
1196static int dmz_recover_mblocks(struct dmz_metadata *zmd, unsigned int dst_set)
1197{
1198 unsigned int src_set = dst_set ^ 0x1;
1199 struct page *page;
1200 int i, ret;
1201
1202 dmz_dev_warn(zmd->sb[dst_set].dev,
1203 "Metadata set %u invalid: recovering", dst_set);
1204
1205 if (dst_set == 0)
1206 zmd->sb[0].block = dmz_start_block(zmd, zmd->sb[0].zone);
1207 else
1208 zmd->sb[1].block = dmz_start_block(zmd, zmd->sb[1].zone);
1209
1210 page = alloc_page(GFP_NOIO);
1211 if (!page)
1212 return -ENOMEM;
1213
1214 /* Copy metadata blocks */
1215 for (i = 1; i < zmd->nr_meta_blocks; i++) {
1216 ret = dmz_rdwr_block(zmd->sb[src_set].dev, REQ_OP_READ,
1217 zmd->sb[src_set].block + i, page);
1218 if (ret)
1219 goto out;
1220 ret = dmz_rdwr_block(zmd->sb[dst_set].dev, REQ_OP_WRITE,
1221 zmd->sb[dst_set].block + i, page);
1222 if (ret)
1223 goto out;
1224 }
1225
1226 /* Finalize with the super block */
1227 if (!zmd->sb[dst_set].mblk) {
1228 zmd->sb[dst_set].mblk = dmz_alloc_mblock(zmd, 0);
1229 if (!zmd->sb[dst_set].mblk) {
1230 ret = -ENOMEM;
1231 goto out;
1232 }
1233 zmd->sb[dst_set].sb = zmd->sb[dst_set].mblk->data;
1234 }
1235
1236 ret = dmz_write_sb(zmd, dst_set);
1237out:
1238 __free_pages(page, 0);
1239
1240 return ret;
1241}
1242
1243/*
1244 * Get super block from disk.
1245 */
1246static int dmz_load_sb(struct dmz_metadata *zmd)
1247{
1248 bool sb_good[2] = {false, false};
1249 u64 sb_gen[2] = {0, 0};
1250 int ret;
1251
1252 if (!zmd->sb[0].zone) {
1253 dmz_zmd_err(zmd, "Primary super block zone not set");
1254 return -ENXIO;
1255 }
1256
1257 /* Read and check the primary super block */
1258 zmd->sb[0].block = dmz_start_block(zmd, zmd->sb[0].zone);
1259 zmd->sb[0].dev = zmd->sb[0].zone->dev;
1260 ret = dmz_get_sb(zmd, &zmd->sb[0], 0);
1261 if (ret) {
1262 dmz_dev_err(zmd->sb[0].dev, "Read primary super block failed");
1263 return ret;
1264 }
1265
1266 ret = dmz_check_sb(zmd, &zmd->sb[0], false);
1267
1268 /* Read and check secondary super block */
1269 if (ret == 0) {
1270 sb_good[0] = true;
1271 if (!zmd->sb[1].zone) {
1272 unsigned int zone_id =
1273 zmd->sb[0].zone->id + zmd->nr_meta_zones;
1274
1275 zmd->sb[1].zone = dmz_get(zmd, zone_id);
1276 }
1277 zmd->sb[1].block = dmz_start_block(zmd, zmd->sb[1].zone);
1278 zmd->sb[1].dev = zmd->sb[0].dev;
1279 ret = dmz_get_sb(zmd, &zmd->sb[1], 1);
1280 } else
1281 ret = dmz_lookup_secondary_sb(zmd);
1282
1283 if (ret) {
1284 dmz_dev_err(zmd->sb[1].dev, "Read secondary super block failed");
1285 return ret;
1286 }
1287
1288 ret = dmz_check_sb(zmd, &zmd->sb[1], false);
1289 if (ret == 0)
1290 sb_good[1] = true;
1291
1292 /* Use highest generation sb first */
1293 if (!sb_good[0] && !sb_good[1]) {
1294 dmz_zmd_err(zmd, "No valid super block found");
1295 return -EIO;
1296 }
1297
1298 if (sb_good[0])
1299 sb_gen[0] = le64_to_cpu(zmd->sb[0].sb->gen);
1300 else {
1301 ret = dmz_recover_mblocks(zmd, 0);
1302 if (ret) {
1303 dmz_dev_err(zmd->sb[0].dev,
1304 "Recovery of superblock 0 failed");
1305 return -EIO;
1306 }
1307 }
1308
1309 if (sb_good[1])
1310 sb_gen[1] = le64_to_cpu(zmd->sb[1].sb->gen);
1311 else {
1312 ret = dmz_recover_mblocks(zmd, 1);
1313
1314 if (ret) {
1315 dmz_dev_err(zmd->sb[1].dev,
1316 "Recovery of superblock 1 failed");
1317 return -EIO;
1318 }
1319 }
1320
1321 if (sb_gen[0] >= sb_gen[1]) {
1322 zmd->sb_gen = sb_gen[0];
1323 zmd->mblk_primary = 0;
1324 } else {
1325 zmd->sb_gen = sb_gen[1];
1326 zmd->mblk_primary = 1;
1327 }
1328
1329 dmz_dev_debug(zmd->sb[zmd->mblk_primary].dev,
1330 "Using super block %u (gen %llu)",
1331 zmd->mblk_primary, zmd->sb_gen);
1332
1333 if (zmd->sb_version > 1) {
1334 int i;
1335 struct dmz_sb *sb;
1336
1337 sb = kzalloc(sizeof(struct dmz_sb), GFP_KERNEL);
1338 if (!sb)
1339 return -ENOMEM;
1340 for (i = 1; i < zmd->nr_devs; i++) {
1341 sb->block = 0;
1342 sb->zone = dmz_get(zmd, zmd->dev[i].zone_offset);
1343 sb->dev = &zmd->dev[i];
1344 if (!dmz_is_meta(sb->zone)) {
1345 dmz_dev_err(sb->dev,
1346 "Tertiary super block zone %u not marked as metadata zone",
1347 sb->zone->id);
1348 ret = -EINVAL;
1349 goto out_kfree;
1350 }
1351 ret = dmz_get_sb(zmd, sb, i + 1);
1352 if (ret) {
1353 dmz_dev_err(sb->dev,
1354 "Read tertiary super block failed");
1355 dmz_free_mblock(zmd, sb->mblk);
1356 goto out_kfree;
1357 }
1358 ret = dmz_check_sb(zmd, sb, true);
1359 dmz_free_mblock(zmd, sb->mblk);
1360 if (ret == -EINVAL)
1361 goto out_kfree;
1362 }
1363 out_kfree:
1364 kfree(sb);
1365 }
1366 return ret;
1367}
1368
1369/*
1370 * Initialize a zone descriptor.
1371 */
1372static int dmz_init_zone(struct blk_zone *blkz, unsigned int num, void *data)
1373{
1374 struct dmz_dev *dev = data;
1375 struct dmz_metadata *zmd = dev->metadata;
1376 int idx = num + dev->zone_offset;
1377 struct dm_zone *zone;
1378
1379 zone = dmz_insert(zmd, idx, dev);
1380 if (IS_ERR(zone))
1381 return PTR_ERR(zone);
1382
1383 if (blkz->len != zmd->zone_nr_sectors) {
1384 if (zmd->sb_version > 1) {
1385 /* Ignore the eventual runt (smaller) zone */
1386 set_bit(DMZ_OFFLINE, &zone->flags);
1387 return 0;
1388 } else if (blkz->start + blkz->len == dev->capacity)
1389 return 0;
1390 return -ENXIO;
1391 }
1392
1393 switch (blkz->type) {
1394 case BLK_ZONE_TYPE_CONVENTIONAL:
1395 set_bit(DMZ_RND, &zone->flags);
1396 break;
1397 case BLK_ZONE_TYPE_SEQWRITE_REQ:
1398 case BLK_ZONE_TYPE_SEQWRITE_PREF:
1399 set_bit(DMZ_SEQ, &zone->flags);
1400 break;
1401 default:
1402 return -ENXIO;
1403 }
1404
1405 if (dmz_is_rnd(zone))
1406 zone->wp_block = 0;
1407 else
1408 zone->wp_block = dmz_sect2blk(blkz->wp - blkz->start);
1409
1410 if (blkz->cond == BLK_ZONE_COND_OFFLINE)
1411 set_bit(DMZ_OFFLINE, &zone->flags);
1412 else if (blkz->cond == BLK_ZONE_COND_READONLY)
1413 set_bit(DMZ_READ_ONLY, &zone->flags);
1414 else {
1415 zmd->nr_useable_zones++;
1416 if (dmz_is_rnd(zone)) {
1417 zmd->nr_rnd_zones++;
1418 if (zmd->nr_devs == 1 && !zmd->sb[0].zone) {
1419 /* Primary super block zone */
1420 zmd->sb[0].zone = zone;
1421 }
1422 }
1423 if (zmd->nr_devs > 1 && num == 0) {
1424 /*
1425 * Tertiary superblock zones are always at the
1426 * start of the zoned devices, so mark them
1427 * as metadata zone.
1428 */
1429 set_bit(DMZ_META, &zone->flags);
1430 }
1431 }
1432 return 0;
1433}
1434
1435static int dmz_emulate_zones(struct dmz_metadata *zmd, struct dmz_dev *dev)
1436{
1437 int idx;
1438 sector_t zone_offset = 0;
1439
1440 for(idx = 0; idx < dev->nr_zones; idx++) {
1441 struct dm_zone *zone;
1442
1443 zone = dmz_insert(zmd, idx, dev);
1444 if (IS_ERR(zone))
1445 return PTR_ERR(zone);
1446 set_bit(DMZ_CACHE, &zone->flags);
1447 zone->wp_block = 0;
1448 zmd->nr_cache_zones++;
1449 zmd->nr_useable_zones++;
1450 if (dev->capacity - zone_offset < zmd->zone_nr_sectors) {
1451 /* Disable runt zone */
1452 set_bit(DMZ_OFFLINE, &zone->flags);
1453 break;
1454 }
1455 zone_offset += zmd->zone_nr_sectors;
1456 }
1457 return 0;
1458}
1459
1460/*
1461 * Free zones descriptors.
1462 */
1463static void dmz_drop_zones(struct dmz_metadata *zmd)
1464{
1465 int idx;
1466
1467 for(idx = 0; idx < zmd->nr_zones; idx++) {
1468 struct dm_zone *zone = xa_load(&zmd->zones, idx);
1469
1470 kfree(zone);
1471 xa_erase(&zmd->zones, idx);
1472 }
1473 xa_destroy(&zmd->zones);
1474}
1475
1476/*
1477 * Allocate and initialize zone descriptors using the zone
1478 * information from disk.
1479 */
1480static int dmz_init_zones(struct dmz_metadata *zmd)
1481{
1482 int i, ret;
1483 struct dmz_dev *zoned_dev = &zmd->dev[0];
1484
1485 /* Init */
1486 zmd->zone_nr_sectors = zmd->dev[0].zone_nr_sectors;
1487 zmd->zone_nr_sectors_shift = ilog2(zmd->zone_nr_sectors);
1488 zmd->zone_nr_blocks = dmz_sect2blk(zmd->zone_nr_sectors);
1489 zmd->zone_nr_blocks_shift = ilog2(zmd->zone_nr_blocks);
1490 zmd->zone_bitmap_size = zmd->zone_nr_blocks >> 3;
1491 zmd->zone_nr_bitmap_blocks =
1492 max_t(sector_t, 1, zmd->zone_bitmap_size >> DMZ_BLOCK_SHIFT);
1493 zmd->zone_bits_per_mblk = min_t(sector_t, zmd->zone_nr_blocks,
1494 DMZ_BLOCK_SIZE_BITS);
1495
1496 /* Allocate zone array */
1497 zmd->nr_zones = 0;
1498 for (i = 0; i < zmd->nr_devs; i++) {
1499 struct dmz_dev *dev = &zmd->dev[i];
1500
1501 dev->metadata = zmd;
1502 zmd->nr_zones += dev->nr_zones;
1503
1504 atomic_set(&dev->unmap_nr_rnd, 0);
1505 INIT_LIST_HEAD(&dev->unmap_rnd_list);
1506 INIT_LIST_HEAD(&dev->map_rnd_list);
1507
1508 atomic_set(&dev->unmap_nr_seq, 0);
1509 INIT_LIST_HEAD(&dev->unmap_seq_list);
1510 INIT_LIST_HEAD(&dev->map_seq_list);
1511 }
1512
1513 if (!zmd->nr_zones) {
1514 DMERR("(%s): No zones found", zmd->devname);
1515 return -ENXIO;
1516 }
1517 xa_init(&zmd->zones);
1518
1519 DMDEBUG("(%s): Using %zu B for zone information",
1520 zmd->devname, sizeof(struct dm_zone) * zmd->nr_zones);
1521
1522 if (zmd->nr_devs > 1) {
1523 ret = dmz_emulate_zones(zmd, &zmd->dev[0]);
1524 if (ret < 0) {
1525 DMDEBUG("(%s): Failed to emulate zones, error %d",
1526 zmd->devname, ret);
1527 dmz_drop_zones(zmd);
1528 return ret;
1529 }
1530
1531 /*
1532 * Primary superblock zone is always at zone 0 when multiple
1533 * drives are present.
1534 */
1535 zmd->sb[0].zone = dmz_get(zmd, 0);
1536
1537 for (i = 1; i < zmd->nr_devs; i++) {
1538 zoned_dev = &zmd->dev[i];
1539
1540 ret = blkdev_report_zones(zoned_dev->bdev, 0,
1541 BLK_ALL_ZONES,
1542 dmz_init_zone, zoned_dev);
1543 if (ret < 0) {
1544 DMDEBUG("(%s): Failed to report zones, error %d",
1545 zmd->devname, ret);
1546 dmz_drop_zones(zmd);
1547 return ret;
1548 }
1549 }
1550 return 0;
1551 }
1552
1553 /*
1554 * Get zone information and initialize zone descriptors. At the same
1555 * time, determine where the super block should be: first block of the
1556 * first randomly writable zone.
1557 */
1558 ret = blkdev_report_zones(zoned_dev->bdev, 0, BLK_ALL_ZONES,
1559 dmz_init_zone, zoned_dev);
1560 if (ret < 0) {
1561 DMDEBUG("(%s): Failed to report zones, error %d",
1562 zmd->devname, ret);
1563 dmz_drop_zones(zmd);
1564 return ret;
1565 }
1566
1567 return 0;
1568}
1569
1570static int dmz_update_zone_cb(struct blk_zone *blkz, unsigned int idx,
1571 void *data)
1572{
1573 struct dm_zone *zone = data;
1574
1575 clear_bit(DMZ_OFFLINE, &zone->flags);
1576 clear_bit(DMZ_READ_ONLY, &zone->flags);
1577 if (blkz->cond == BLK_ZONE_COND_OFFLINE)
1578 set_bit(DMZ_OFFLINE, &zone->flags);
1579 else if (blkz->cond == BLK_ZONE_COND_READONLY)
1580 set_bit(DMZ_READ_ONLY, &zone->flags);
1581
1582 if (dmz_is_seq(zone))
1583 zone->wp_block = dmz_sect2blk(blkz->wp - blkz->start);
1584 else
1585 zone->wp_block = 0;
1586 return 0;
1587}
1588
1589/*
1590 * Update a zone information.
1591 */
1592static int dmz_update_zone(struct dmz_metadata *zmd, struct dm_zone *zone)
1593{
1594 struct dmz_dev *dev = zone->dev;
1595 unsigned int noio_flag;
1596 int ret;
1597
1598 if (dev->flags & DMZ_BDEV_REGULAR)
1599 return 0;
1600
1601 /*
1602 * Get zone information from disk. Since blkdev_report_zones() uses
1603 * GFP_KERNEL by default for memory allocations, set the per-task
1604 * PF_MEMALLOC_NOIO flag so that all allocations are done as if
1605 * GFP_NOIO was specified.
1606 */
1607 noio_flag = memalloc_noio_save();
1608 ret = blkdev_report_zones(dev->bdev, dmz_start_sect(zmd, zone), 1,
1609 dmz_update_zone_cb, zone);
1610 memalloc_noio_restore(noio_flag);
1611
1612 if (ret == 0)
1613 ret = -EIO;
1614 if (ret < 0) {
1615 dmz_dev_err(dev, "Get zone %u report failed",
1616 zone->id);
1617 dmz_check_bdev(dev);
1618 return ret;
1619 }
1620
1621 return 0;
1622}
1623
1624/*
1625 * Check a zone write pointer position when the zone is marked
1626 * with the sequential write error flag.
1627 */
1628static int dmz_handle_seq_write_err(struct dmz_metadata *zmd,
1629 struct dm_zone *zone)
1630{
1631 struct dmz_dev *dev = zone->dev;
1632 unsigned int wp = 0;
1633 int ret;
1634
1635 wp = zone->wp_block;
1636 ret = dmz_update_zone(zmd, zone);
1637 if (ret)
1638 return ret;
1639
1640 dmz_dev_warn(dev, "Processing zone %u write error (zone wp %u/%u)",
1641 zone->id, zone->wp_block, wp);
1642
1643 if (zone->wp_block < wp) {
1644 dmz_invalidate_blocks(zmd, zone, zone->wp_block,
1645 wp - zone->wp_block);
1646 }
1647
1648 return 0;
1649}
1650
1651/*
1652 * Reset a zone write pointer.
1653 */
1654static int dmz_reset_zone(struct dmz_metadata *zmd, struct dm_zone *zone)
1655{
1656 int ret;
1657
1658 /*
1659 * Ignore offline zones, read only zones,
1660 * and conventional zones.
1661 */
1662 if (dmz_is_offline(zone) ||
1663 dmz_is_readonly(zone) ||
1664 dmz_is_rnd(zone))
1665 return 0;
1666
1667 if (!dmz_is_empty(zone) || dmz_seq_write_err(zone)) {
1668 struct dmz_dev *dev = zone->dev;
1669
1670 ret = blkdev_zone_mgmt(dev->bdev, REQ_OP_ZONE_RESET,
1671 dmz_start_sect(zmd, zone),
1672 zmd->zone_nr_sectors, GFP_NOIO);
1673 if (ret) {
1674 dmz_dev_err(dev, "Reset zone %u failed %d",
1675 zone->id, ret);
1676 return ret;
1677 }
1678 }
1679
1680 /* Clear write error bit and rewind write pointer position */
1681 clear_bit(DMZ_SEQ_WRITE_ERR, &zone->flags);
1682 zone->wp_block = 0;
1683
1684 return 0;
1685}
1686
1687static void dmz_get_zone_weight(struct dmz_metadata *zmd, struct dm_zone *zone);
1688
1689/*
1690 * Initialize chunk mapping.
1691 */
1692static int dmz_load_mapping(struct dmz_metadata *zmd)
1693{
1694 struct dm_zone *dzone, *bzone;
1695 struct dmz_mblock *dmap_mblk = NULL;
1696 struct dmz_map *dmap;
1697 unsigned int i = 0, e = 0, chunk = 0;
1698 unsigned int dzone_id;
1699 unsigned int bzone_id;
1700
1701 /* Metadata block array for the chunk mapping table */
1702 zmd->map_mblk = kcalloc(zmd->nr_map_blocks,
1703 sizeof(struct dmz_mblk *), GFP_KERNEL);
1704 if (!zmd->map_mblk)
1705 return -ENOMEM;
1706
1707 /* Get chunk mapping table blocks and initialize zone mapping */
1708 while (chunk < zmd->nr_chunks) {
1709 if (!dmap_mblk) {
1710 /* Get mapping block */
1711 dmap_mblk = dmz_get_mblock(zmd, i + 1);
1712 if (IS_ERR(dmap_mblk))
1713 return PTR_ERR(dmap_mblk);
1714 zmd->map_mblk[i] = dmap_mblk;
1715 dmap = (struct dmz_map *) dmap_mblk->data;
1716 i++;
1717 e = 0;
1718 }
1719
1720 /* Check data zone */
1721 dzone_id = le32_to_cpu(dmap[e].dzone_id);
1722 if (dzone_id == DMZ_MAP_UNMAPPED)
1723 goto next;
1724
1725 if (dzone_id >= zmd->nr_zones) {
1726 dmz_zmd_err(zmd, "Chunk %u mapping: invalid data zone ID %u",
1727 chunk, dzone_id);
1728 return -EIO;
1729 }
1730
1731 dzone = dmz_get(zmd, dzone_id);
1732 if (!dzone) {
1733 dmz_zmd_err(zmd, "Chunk %u mapping: data zone %u not present",
1734 chunk, dzone_id);
1735 return -EIO;
1736 }
1737 set_bit(DMZ_DATA, &dzone->flags);
1738 dzone->chunk = chunk;
1739 dmz_get_zone_weight(zmd, dzone);
1740
1741 if (dmz_is_cache(dzone))
1742 list_add_tail(&dzone->link, &zmd->map_cache_list);
1743 else if (dmz_is_rnd(dzone))
1744 list_add_tail(&dzone->link, &dzone->dev->map_rnd_list);
1745 else
1746 list_add_tail(&dzone->link, &dzone->dev->map_seq_list);
1747
1748 /* Check buffer zone */
1749 bzone_id = le32_to_cpu(dmap[e].bzone_id);
1750 if (bzone_id == DMZ_MAP_UNMAPPED)
1751 goto next;
1752
1753 if (bzone_id >= zmd->nr_zones) {
1754 dmz_zmd_err(zmd, "Chunk %u mapping: invalid buffer zone ID %u",
1755 chunk, bzone_id);
1756 return -EIO;
1757 }
1758
1759 bzone = dmz_get(zmd, bzone_id);
1760 if (!bzone) {
1761 dmz_zmd_err(zmd, "Chunk %u mapping: buffer zone %u not present",
1762 chunk, bzone_id);
1763 return -EIO;
1764 }
1765 if (!dmz_is_rnd(bzone) && !dmz_is_cache(bzone)) {
1766 dmz_zmd_err(zmd, "Chunk %u mapping: invalid buffer zone %u",
1767 chunk, bzone_id);
1768 return -EIO;
1769 }
1770
1771 set_bit(DMZ_DATA, &bzone->flags);
1772 set_bit(DMZ_BUF, &bzone->flags);
1773 bzone->chunk = chunk;
1774 bzone->bzone = dzone;
1775 dzone->bzone = bzone;
1776 dmz_get_zone_weight(zmd, bzone);
1777 if (dmz_is_cache(bzone))
1778 list_add_tail(&bzone->link, &zmd->map_cache_list);
1779 else
1780 list_add_tail(&bzone->link, &bzone->dev->map_rnd_list);
1781next:
1782 chunk++;
1783 e++;
1784 if (e >= DMZ_MAP_ENTRIES)
1785 dmap_mblk = NULL;
1786 }
1787
1788 /*
1789 * At this point, only meta zones and mapped data zones were
1790 * fully initialized. All remaining zones are unmapped data
1791 * zones. Finish initializing those here.
1792 */
1793 for (i = 0; i < zmd->nr_zones; i++) {
1794 dzone = dmz_get(zmd, i);
1795 if (!dzone)
1796 continue;
1797 if (dmz_is_meta(dzone))
1798 continue;
1799 if (dmz_is_offline(dzone))
1800 continue;
1801
1802 if (dmz_is_cache(dzone))
1803 zmd->nr_cache++;
1804 else if (dmz_is_rnd(dzone))
1805 dzone->dev->nr_rnd++;
1806 else
1807 dzone->dev->nr_seq++;
1808
1809 if (dmz_is_data(dzone)) {
1810 /* Already initialized */
1811 continue;
1812 }
1813
1814 /* Unmapped data zone */
1815 set_bit(DMZ_DATA, &dzone->flags);
1816 dzone->chunk = DMZ_MAP_UNMAPPED;
1817 if (dmz_is_cache(dzone)) {
1818 list_add_tail(&dzone->link, &zmd->unmap_cache_list);
1819 atomic_inc(&zmd->unmap_nr_cache);
1820 } else if (dmz_is_rnd(dzone)) {
1821 list_add_tail(&dzone->link,
1822 &dzone->dev->unmap_rnd_list);
1823 atomic_inc(&dzone->dev->unmap_nr_rnd);
1824 } else if (atomic_read(&zmd->nr_reserved_seq_zones) < zmd->nr_reserved_seq) {
1825 list_add_tail(&dzone->link, &zmd->reserved_seq_zones_list);
1826 set_bit(DMZ_RESERVED, &dzone->flags);
1827 atomic_inc(&zmd->nr_reserved_seq_zones);
1828 dzone->dev->nr_seq--;
1829 } else {
1830 list_add_tail(&dzone->link,
1831 &dzone->dev->unmap_seq_list);
1832 atomic_inc(&dzone->dev->unmap_nr_seq);
1833 }
1834 }
1835
1836 return 0;
1837}
1838
1839/*
1840 * Set a data chunk mapping.
1841 */
1842static void dmz_set_chunk_mapping(struct dmz_metadata *zmd, unsigned int chunk,
1843 unsigned int dzone_id, unsigned int bzone_id)
1844{
1845 struct dmz_mblock *dmap_mblk = zmd->map_mblk[chunk >> DMZ_MAP_ENTRIES_SHIFT];
1846 struct dmz_map *dmap = (struct dmz_map *) dmap_mblk->data;
1847 int map_idx = chunk & DMZ_MAP_ENTRIES_MASK;
1848
1849 dmap[map_idx].dzone_id = cpu_to_le32(dzone_id);
1850 dmap[map_idx].bzone_id = cpu_to_le32(bzone_id);
1851 dmz_dirty_mblock(zmd, dmap_mblk);
1852}
1853
1854/*
1855 * The list of mapped zones is maintained in LRU order.
1856 * This rotates a zone at the end of its map list.
1857 */
1858static void __dmz_lru_zone(struct dmz_metadata *zmd, struct dm_zone *zone)
1859{
1860 if (list_empty(&zone->link))
1861 return;
1862
1863 list_del_init(&zone->link);
1864 if (dmz_is_seq(zone)) {
1865 /* LRU rotate sequential zone */
1866 list_add_tail(&zone->link, &zone->dev->map_seq_list);
1867 } else if (dmz_is_cache(zone)) {
1868 /* LRU rotate cache zone */
1869 list_add_tail(&zone->link, &zmd->map_cache_list);
1870 } else {
1871 /* LRU rotate random zone */
1872 list_add_tail(&zone->link, &zone->dev->map_rnd_list);
1873 }
1874}
1875
1876/*
1877 * The list of mapped random zones is maintained
1878 * in LRU order. This rotates a zone at the end of the list.
1879 */
1880static void dmz_lru_zone(struct dmz_metadata *zmd, struct dm_zone *zone)
1881{
1882 __dmz_lru_zone(zmd, zone);
1883 if (zone->bzone)
1884 __dmz_lru_zone(zmd, zone->bzone);
1885}
1886
1887/*
1888 * Wait for any zone to be freed.
1889 */
1890static void dmz_wait_for_free_zones(struct dmz_metadata *zmd)
1891{
1892 DEFINE_WAIT(wait);
1893
1894 prepare_to_wait(&zmd->free_wq, &wait, TASK_UNINTERRUPTIBLE);
1895 dmz_unlock_map(zmd);
1896 dmz_unlock_metadata(zmd);
1897
1898 io_schedule_timeout(HZ);
1899
1900 dmz_lock_metadata(zmd);
1901 dmz_lock_map(zmd);
1902 finish_wait(&zmd->free_wq, &wait);
1903}
1904
1905/*
1906 * Lock a zone for reclaim (set the zone RECLAIM bit).
1907 * Returns false if the zone cannot be locked or if it is already locked
1908 * and 1 otherwise.
1909 */
1910int dmz_lock_zone_reclaim(struct dm_zone *zone)
1911{
1912 /* Active zones cannot be reclaimed */
1913 if (dmz_is_active(zone))
1914 return 0;
1915
1916 return !test_and_set_bit(DMZ_RECLAIM, &zone->flags);
1917}
1918
1919/*
1920 * Clear a zone reclaim flag.
1921 */
1922void dmz_unlock_zone_reclaim(struct dm_zone *zone)
1923{
1924 WARN_ON(dmz_is_active(zone));
1925 WARN_ON(!dmz_in_reclaim(zone));
1926
1927 clear_bit_unlock(DMZ_RECLAIM, &zone->flags);
1928 smp_mb__after_atomic();
1929 wake_up_bit(&zone->flags, DMZ_RECLAIM);
1930}
1931
1932/*
1933 * Wait for a zone reclaim to complete.
1934 */
1935static void dmz_wait_for_reclaim(struct dmz_metadata *zmd, struct dm_zone *zone)
1936{
1937 dmz_unlock_map(zmd);
1938 dmz_unlock_metadata(zmd);
1939 set_bit(DMZ_RECLAIM_TERMINATE, &zone->flags);
1940 wait_on_bit_timeout(&zone->flags, DMZ_RECLAIM, TASK_UNINTERRUPTIBLE, HZ);
1941 clear_bit(DMZ_RECLAIM_TERMINATE, &zone->flags);
1942 dmz_lock_metadata(zmd);
1943 dmz_lock_map(zmd);
1944}
1945
1946/*
1947 * Select a cache or random write zone for reclaim.
1948 */
1949static struct dm_zone *dmz_get_rnd_zone_for_reclaim(struct dmz_metadata *zmd,
1950 unsigned int idx, bool idle)
1951{
1952 struct dm_zone *dzone = NULL;
1953 struct dm_zone *zone, *maxw_z = NULL;
1954 struct list_head *zone_list;
1955
1956 /* If we have cache zones select from the cache zone list */
1957 if (zmd->nr_cache) {
1958 zone_list = &zmd->map_cache_list;
1959 /* Try to relaim random zones, too, when idle */
1960 if (idle && list_empty(zone_list))
1961 zone_list = &zmd->dev[idx].map_rnd_list;
1962 } else
1963 zone_list = &zmd->dev[idx].map_rnd_list;
1964
1965 /*
1966 * Find the buffer zone with the heaviest weight or the first (oldest)
1967 * data zone that can be reclaimed.
1968 */
1969 list_for_each_entry(zone, zone_list, link) {
1970 if (dmz_is_buf(zone)) {
1971 dzone = zone->bzone;
1972 if (dmz_is_rnd(dzone) && dzone->dev->dev_idx != idx)
1973 continue;
1974 if (!maxw_z || maxw_z->weight < dzone->weight)
1975 maxw_z = dzone;
1976 } else {
1977 dzone = zone;
1978 if (dmz_lock_zone_reclaim(dzone))
1979 return dzone;
1980 }
1981 }
1982
1983 if (maxw_z && dmz_lock_zone_reclaim(maxw_z))
1984 return maxw_z;
1985
1986 /*
1987 * If we come here, none of the zones inspected could be locked for
1988 * reclaim. Try again, being more aggressive, that is, find the
1989 * first zone that can be reclaimed regardless of its weitght.
1990 */
1991 list_for_each_entry(zone, zone_list, link) {
1992 if (dmz_is_buf(zone)) {
1993 dzone = zone->bzone;
1994 if (dmz_is_rnd(dzone) && dzone->dev->dev_idx != idx)
1995 continue;
1996 } else
1997 dzone = zone;
1998 if (dmz_lock_zone_reclaim(dzone))
1999 return dzone;
2000 }
2001
2002 return NULL;
2003}
2004
2005/*
2006 * Select a buffered sequential zone for reclaim.
2007 */
2008static struct dm_zone *dmz_get_seq_zone_for_reclaim(struct dmz_metadata *zmd,
2009 unsigned int idx)
2010{
2011 struct dm_zone *zone;
2012
2013 list_for_each_entry(zone, &zmd->dev[idx].map_seq_list, link) {
2014 if (!zone->bzone)
2015 continue;
2016 if (dmz_lock_zone_reclaim(zone))
2017 return zone;
2018 }
2019
2020 return NULL;
2021}
2022
2023/*
2024 * Select a zone for reclaim.
2025 */
2026struct dm_zone *dmz_get_zone_for_reclaim(struct dmz_metadata *zmd,
2027 unsigned int dev_idx, bool idle)
2028{
2029 struct dm_zone *zone = NULL;
2030
2031 /*
2032 * Search for a zone candidate to reclaim: 2 cases are possible.
2033 * (1) There is no free sequential zones. Then a random data zone
2034 * cannot be reclaimed. So choose a sequential zone to reclaim so
2035 * that afterward a random zone can be reclaimed.
2036 * (2) At least one free sequential zone is available, then choose
2037 * the oldest random zone (data or buffer) that can be locked.
2038 */
2039 dmz_lock_map(zmd);
2040 if (list_empty(&zmd->reserved_seq_zones_list))
2041 zone = dmz_get_seq_zone_for_reclaim(zmd, dev_idx);
2042 if (!zone)
2043 zone = dmz_get_rnd_zone_for_reclaim(zmd, dev_idx, idle);
2044 dmz_unlock_map(zmd);
2045
2046 return zone;
2047}
2048
2049/*
2050 * Get the zone mapping a chunk, if the chunk is mapped already.
2051 * If no mapping exist and the operation is WRITE, a zone is
2052 * allocated and used to map the chunk.
2053 * The zone returned will be set to the active state.
2054 */
2055struct dm_zone *dmz_get_chunk_mapping(struct dmz_metadata *zmd, unsigned int chunk, int op)
2056{
2057 struct dmz_mblock *dmap_mblk = zmd->map_mblk[chunk >> DMZ_MAP_ENTRIES_SHIFT];
2058 struct dmz_map *dmap = (struct dmz_map *) dmap_mblk->data;
2059 int dmap_idx = chunk & DMZ_MAP_ENTRIES_MASK;
2060 unsigned int dzone_id;
2061 struct dm_zone *dzone = NULL;
2062 int ret = 0;
2063 int alloc_flags = zmd->nr_cache ? DMZ_ALLOC_CACHE : DMZ_ALLOC_RND;
2064
2065 dmz_lock_map(zmd);
2066again:
2067 /* Get the chunk mapping */
2068 dzone_id = le32_to_cpu(dmap[dmap_idx].dzone_id);
2069 if (dzone_id == DMZ_MAP_UNMAPPED) {
2070 /*
2071 * Read or discard in unmapped chunks are fine. But for
2072 * writes, we need a mapping, so get one.
2073 */
2074 if (op != REQ_OP_WRITE)
2075 goto out;
2076
2077 /* Allocate a random zone */
2078 dzone = dmz_alloc_zone(zmd, 0, alloc_flags);
2079 if (!dzone) {
2080 if (dmz_dev_is_dying(zmd)) {
2081 dzone = ERR_PTR(-EIO);
2082 goto out;
2083 }
2084 dmz_wait_for_free_zones(zmd);
2085 goto again;
2086 }
2087
2088 dmz_map_zone(zmd, dzone, chunk);
2089
2090 } else {
2091 /* The chunk is already mapped: get the mapping zone */
2092 dzone = dmz_get(zmd, dzone_id);
2093 if (!dzone) {
2094 dzone = ERR_PTR(-EIO);
2095 goto out;
2096 }
2097 if (dzone->chunk != chunk) {
2098 dzone = ERR_PTR(-EIO);
2099 goto out;
2100 }
2101
2102 /* Repair write pointer if the sequential dzone has error */
2103 if (dmz_seq_write_err(dzone)) {
2104 ret = dmz_handle_seq_write_err(zmd, dzone);
2105 if (ret) {
2106 dzone = ERR_PTR(-EIO);
2107 goto out;
2108 }
2109 clear_bit(DMZ_SEQ_WRITE_ERR, &dzone->flags);
2110 }
2111 }
2112
2113 /*
2114 * If the zone is being reclaimed, the chunk mapping may change
2115 * to a different zone. So wait for reclaim and retry. Otherwise,
2116 * activate the zone (this will prevent reclaim from touching it).
2117 */
2118 if (dmz_in_reclaim(dzone)) {
2119 dmz_wait_for_reclaim(zmd, dzone);
2120 goto again;
2121 }
2122 dmz_activate_zone(dzone);
2123 dmz_lru_zone(zmd, dzone);
2124out:
2125 dmz_unlock_map(zmd);
2126
2127 return dzone;
2128}
2129
2130/*
2131 * Write and discard change the block validity of data zones and their buffer
2132 * zones. Check here that valid blocks are still present. If all blocks are
2133 * invalid, the zones can be unmapped on the fly without waiting for reclaim
2134 * to do it.
2135 */
2136void dmz_put_chunk_mapping(struct dmz_metadata *zmd, struct dm_zone *dzone)
2137{
2138 struct dm_zone *bzone;
2139
2140 dmz_lock_map(zmd);
2141
2142 bzone = dzone->bzone;
2143 if (bzone) {
2144 if (dmz_weight(bzone))
2145 dmz_lru_zone(zmd, bzone);
2146 else {
2147 /* Empty buffer zone: reclaim it */
2148 dmz_unmap_zone(zmd, bzone);
2149 dmz_free_zone(zmd, bzone);
2150 bzone = NULL;
2151 }
2152 }
2153
2154 /* Deactivate the data zone */
2155 dmz_deactivate_zone(dzone);
2156 if (dmz_is_active(dzone) || bzone || dmz_weight(dzone))
2157 dmz_lru_zone(zmd, dzone);
2158 else {
2159 /* Unbuffered inactive empty data zone: reclaim it */
2160 dmz_unmap_zone(zmd, dzone);
2161 dmz_free_zone(zmd, dzone);
2162 }
2163
2164 dmz_unlock_map(zmd);
2165}
2166
2167/*
2168 * Allocate and map a random zone to buffer a chunk
2169 * already mapped to a sequential zone.
2170 */
2171struct dm_zone *dmz_get_chunk_buffer(struct dmz_metadata *zmd,
2172 struct dm_zone *dzone)
2173{
2174 struct dm_zone *bzone;
2175 int alloc_flags = zmd->nr_cache ? DMZ_ALLOC_CACHE : DMZ_ALLOC_RND;
2176
2177 dmz_lock_map(zmd);
2178again:
2179 bzone = dzone->bzone;
2180 if (bzone)
2181 goto out;
2182
2183 /* Allocate a random zone */
2184 bzone = dmz_alloc_zone(zmd, 0, alloc_flags);
2185 if (!bzone) {
2186 if (dmz_dev_is_dying(zmd)) {
2187 bzone = ERR_PTR(-EIO);
2188 goto out;
2189 }
2190 dmz_wait_for_free_zones(zmd);
2191 goto again;
2192 }
2193
2194 /* Update the chunk mapping */
2195 dmz_set_chunk_mapping(zmd, dzone->chunk, dzone->id, bzone->id);
2196
2197 set_bit(DMZ_BUF, &bzone->flags);
2198 bzone->chunk = dzone->chunk;
2199 bzone->bzone = dzone;
2200 dzone->bzone = bzone;
2201 if (dmz_is_cache(bzone))
2202 list_add_tail(&bzone->link, &zmd->map_cache_list);
2203 else
2204 list_add_tail(&bzone->link, &bzone->dev->map_rnd_list);
2205out:
2206 dmz_unlock_map(zmd);
2207
2208 return bzone;
2209}
2210
2211/*
2212 * Get an unmapped (free) zone.
2213 * This must be called with the mapping lock held.
2214 */
2215struct dm_zone *dmz_alloc_zone(struct dmz_metadata *zmd, unsigned int dev_idx,
2216 unsigned long flags)
2217{
2218 struct list_head *list;
2219 struct dm_zone *zone;
2220 int i;
2221
2222 /* Schedule reclaim to ensure free zones are available */
2223 if (!(flags & DMZ_ALLOC_RECLAIM)) {
2224 for (i = 0; i < zmd->nr_devs; i++)
2225 dmz_schedule_reclaim(zmd->dev[i].reclaim);
2226 }
2227
2228 i = 0;
2229again:
2230 if (flags & DMZ_ALLOC_CACHE)
2231 list = &zmd->unmap_cache_list;
2232 else if (flags & DMZ_ALLOC_RND)
2233 list = &zmd->dev[dev_idx].unmap_rnd_list;
2234 else
2235 list = &zmd->dev[dev_idx].unmap_seq_list;
2236
2237 if (list_empty(list)) {
2238 /*
2239 * No free zone: return NULL if this is for not reclaim.
2240 */
2241 if (!(flags & DMZ_ALLOC_RECLAIM))
2242 return NULL;
2243 /*
2244 * Try to allocate from other devices
2245 */
2246 if (i < zmd->nr_devs) {
2247 dev_idx = (dev_idx + 1) % zmd->nr_devs;
2248 i++;
2249 goto again;
2250 }
2251
2252 /*
2253 * Fallback to the reserved sequential zones
2254 */
2255 zone = list_first_entry_or_null(&zmd->reserved_seq_zones_list,
2256 struct dm_zone, link);
2257 if (zone) {
2258 list_del_init(&zone->link);
2259 atomic_dec(&zmd->nr_reserved_seq_zones);
2260 }
2261 return zone;
2262 }
2263
2264 zone = list_first_entry(list, struct dm_zone, link);
2265 list_del_init(&zone->link);
2266
2267 if (dmz_is_cache(zone))
2268 atomic_dec(&zmd->unmap_nr_cache);
2269 else if (dmz_is_rnd(zone))
2270 atomic_dec(&zone->dev->unmap_nr_rnd);
2271 else
2272 atomic_dec(&zone->dev->unmap_nr_seq);
2273
2274 if (dmz_is_offline(zone)) {
2275 dmz_zmd_warn(zmd, "Zone %u is offline", zone->id);
2276 zone = NULL;
2277 goto again;
2278 }
2279 if (dmz_is_meta(zone)) {
2280 dmz_zmd_warn(zmd, "Zone %u has metadata", zone->id);
2281 zone = NULL;
2282 goto again;
2283 }
2284 return zone;
2285}
2286
2287/*
2288 * Free a zone.
2289 * This must be called with the mapping lock held.
2290 */
2291void dmz_free_zone(struct dmz_metadata *zmd, struct dm_zone *zone)
2292{
2293 /* If this is a sequential zone, reset it */
2294 if (dmz_is_seq(zone))
2295 dmz_reset_zone(zmd, zone);
2296
2297 /* Return the zone to its type unmap list */
2298 if (dmz_is_cache(zone)) {
2299 list_add_tail(&zone->link, &zmd->unmap_cache_list);
2300 atomic_inc(&zmd->unmap_nr_cache);
2301 } else if (dmz_is_rnd(zone)) {
2302 list_add_tail(&zone->link, &zone->dev->unmap_rnd_list);
2303 atomic_inc(&zone->dev->unmap_nr_rnd);
2304 } else if (dmz_is_reserved(zone)) {
2305 list_add_tail(&zone->link, &zmd->reserved_seq_zones_list);
2306 atomic_inc(&zmd->nr_reserved_seq_zones);
2307 } else {
2308 list_add_tail(&zone->link, &zone->dev->unmap_seq_list);
2309 atomic_inc(&zone->dev->unmap_nr_seq);
2310 }
2311
2312 wake_up_all(&zmd->free_wq);
2313}
2314
2315/*
2316 * Map a chunk to a zone.
2317 * This must be called with the mapping lock held.
2318 */
2319void dmz_map_zone(struct dmz_metadata *zmd, struct dm_zone *dzone,
2320 unsigned int chunk)
2321{
2322 /* Set the chunk mapping */
2323 dmz_set_chunk_mapping(zmd, chunk, dzone->id,
2324 DMZ_MAP_UNMAPPED);
2325 dzone->chunk = chunk;
2326 if (dmz_is_cache(dzone))
2327 list_add_tail(&dzone->link, &zmd->map_cache_list);
2328 else if (dmz_is_rnd(dzone))
2329 list_add_tail(&dzone->link, &dzone->dev->map_rnd_list);
2330 else
2331 list_add_tail(&dzone->link, &dzone->dev->map_seq_list);
2332}
2333
2334/*
2335 * Unmap a zone.
2336 * This must be called with the mapping lock held.
2337 */
2338void dmz_unmap_zone(struct dmz_metadata *zmd, struct dm_zone *zone)
2339{
2340 unsigned int chunk = zone->chunk;
2341 unsigned int dzone_id;
2342
2343 if (chunk == DMZ_MAP_UNMAPPED) {
2344 /* Already unmapped */
2345 return;
2346 }
2347
2348 if (test_and_clear_bit(DMZ_BUF, &zone->flags)) {
2349 /*
2350 * Unmapping the chunk buffer zone: clear only
2351 * the chunk buffer mapping
2352 */
2353 dzone_id = zone->bzone->id;
2354 zone->bzone->bzone = NULL;
2355 zone->bzone = NULL;
2356
2357 } else {
2358 /*
2359 * Unmapping the chunk data zone: the zone must
2360 * not be buffered.
2361 */
2362 if (WARN_ON(zone->bzone)) {
2363 zone->bzone->bzone = NULL;
2364 zone->bzone = NULL;
2365 }
2366 dzone_id = DMZ_MAP_UNMAPPED;
2367 }
2368
2369 dmz_set_chunk_mapping(zmd, chunk, dzone_id, DMZ_MAP_UNMAPPED);
2370
2371 zone->chunk = DMZ_MAP_UNMAPPED;
2372 list_del_init(&zone->link);
2373}
2374
2375/*
2376 * Set @nr_bits bits in @bitmap starting from @bit.
2377 * Return the number of bits changed from 0 to 1.
2378 */
2379static unsigned int dmz_set_bits(unsigned long *bitmap,
2380 unsigned int bit, unsigned int nr_bits)
2381{
2382 unsigned long *addr;
2383 unsigned int end = bit + nr_bits;
2384 unsigned int n = 0;
2385
2386 while (bit < end) {
2387 if (((bit & (BITS_PER_LONG - 1)) == 0) &&
2388 ((end - bit) >= BITS_PER_LONG)) {
2389 /* Try to set the whole word at once */
2390 addr = bitmap + BIT_WORD(bit);
2391 if (*addr == 0) {
2392 *addr = ULONG_MAX;
2393 n += BITS_PER_LONG;
2394 bit += BITS_PER_LONG;
2395 continue;
2396 }
2397 }
2398
2399 if (!test_and_set_bit(bit, bitmap))
2400 n++;
2401 bit++;
2402 }
2403
2404 return n;
2405}
2406
2407/*
2408 * Get the bitmap block storing the bit for chunk_block in zone.
2409 */
2410static struct dmz_mblock *dmz_get_bitmap(struct dmz_metadata *zmd,
2411 struct dm_zone *zone,
2412 sector_t chunk_block)
2413{
2414 sector_t bitmap_block = 1 + zmd->nr_map_blocks +
2415 (sector_t)(zone->id * zmd->zone_nr_bitmap_blocks) +
2416 (chunk_block >> DMZ_BLOCK_SHIFT_BITS);
2417
2418 return dmz_get_mblock(zmd, bitmap_block);
2419}
2420
2421/*
2422 * Copy the valid blocks bitmap of from_zone to the bitmap of to_zone.
2423 */
2424int dmz_copy_valid_blocks(struct dmz_metadata *zmd, struct dm_zone *from_zone,
2425 struct dm_zone *to_zone)
2426{
2427 struct dmz_mblock *from_mblk, *to_mblk;
2428 sector_t chunk_block = 0;
2429
2430 /* Get the zones bitmap blocks */
2431 while (chunk_block < zmd->zone_nr_blocks) {
2432 from_mblk = dmz_get_bitmap(zmd, from_zone, chunk_block);
2433 if (IS_ERR(from_mblk))
2434 return PTR_ERR(from_mblk);
2435 to_mblk = dmz_get_bitmap(zmd, to_zone, chunk_block);
2436 if (IS_ERR(to_mblk)) {
2437 dmz_release_mblock(zmd, from_mblk);
2438 return PTR_ERR(to_mblk);
2439 }
2440
2441 memcpy(to_mblk->data, from_mblk->data, DMZ_BLOCK_SIZE);
2442 dmz_dirty_mblock(zmd, to_mblk);
2443
2444 dmz_release_mblock(zmd, to_mblk);
2445 dmz_release_mblock(zmd, from_mblk);
2446
2447 chunk_block += zmd->zone_bits_per_mblk;
2448 }
2449
2450 to_zone->weight = from_zone->weight;
2451
2452 return 0;
2453}
2454
2455/*
2456 * Merge the valid blocks bitmap of from_zone into the bitmap of to_zone,
2457 * starting from chunk_block.
2458 */
2459int dmz_merge_valid_blocks(struct dmz_metadata *zmd, struct dm_zone *from_zone,
2460 struct dm_zone *to_zone, sector_t chunk_block)
2461{
2462 unsigned int nr_blocks;
2463 int ret;
2464
2465 /* Get the zones bitmap blocks */
2466 while (chunk_block < zmd->zone_nr_blocks) {
2467 /* Get a valid region from the source zone */
2468 ret = dmz_first_valid_block(zmd, from_zone, &chunk_block);
2469 if (ret <= 0)
2470 return ret;
2471
2472 nr_blocks = ret;
2473 ret = dmz_validate_blocks(zmd, to_zone, chunk_block, nr_blocks);
2474 if (ret)
2475 return ret;
2476
2477 chunk_block += nr_blocks;
2478 }
2479
2480 return 0;
2481}
2482
2483/*
2484 * Validate all the blocks in the range [block..block+nr_blocks-1].
2485 */
2486int dmz_validate_blocks(struct dmz_metadata *zmd, struct dm_zone *zone,
2487 sector_t chunk_block, unsigned int nr_blocks)
2488{
2489 unsigned int count, bit, nr_bits;
2490 unsigned int zone_nr_blocks = zmd->zone_nr_blocks;
2491 struct dmz_mblock *mblk;
2492 unsigned int n = 0;
2493
2494 dmz_zmd_debug(zmd, "=> VALIDATE zone %u, block %llu, %u blocks",
2495 zone->id, (unsigned long long)chunk_block,
2496 nr_blocks);
2497
2498 WARN_ON(chunk_block + nr_blocks > zone_nr_blocks);
2499
2500 while (nr_blocks) {
2501 /* Get bitmap block */
2502 mblk = dmz_get_bitmap(zmd, zone, chunk_block);
2503 if (IS_ERR(mblk))
2504 return PTR_ERR(mblk);
2505
2506 /* Set bits */
2507 bit = chunk_block & DMZ_BLOCK_MASK_BITS;
2508 nr_bits = min(nr_blocks, zmd->zone_bits_per_mblk - bit);
2509
2510 count = dmz_set_bits((unsigned long *)mblk->data, bit, nr_bits);
2511 if (count) {
2512 dmz_dirty_mblock(zmd, mblk);
2513 n += count;
2514 }
2515 dmz_release_mblock(zmd, mblk);
2516
2517 nr_blocks -= nr_bits;
2518 chunk_block += nr_bits;
2519 }
2520
2521 if (likely(zone->weight + n <= zone_nr_blocks))
2522 zone->weight += n;
2523 else {
2524 dmz_zmd_warn(zmd, "Zone %u: weight %u should be <= %u",
2525 zone->id, zone->weight,
2526 zone_nr_blocks - n);
2527 zone->weight = zone_nr_blocks;
2528 }
2529
2530 return 0;
2531}
2532
2533/*
2534 * Clear nr_bits bits in bitmap starting from bit.
2535 * Return the number of bits cleared.
2536 */
2537static int dmz_clear_bits(unsigned long *bitmap, int bit, int nr_bits)
2538{
2539 unsigned long *addr;
2540 int end = bit + nr_bits;
2541 int n = 0;
2542
2543 while (bit < end) {
2544 if (((bit & (BITS_PER_LONG - 1)) == 0) &&
2545 ((end - bit) >= BITS_PER_LONG)) {
2546 /* Try to clear whole word at once */
2547 addr = bitmap + BIT_WORD(bit);
2548 if (*addr == ULONG_MAX) {
2549 *addr = 0;
2550 n += BITS_PER_LONG;
2551 bit += BITS_PER_LONG;
2552 continue;
2553 }
2554 }
2555
2556 if (test_and_clear_bit(bit, bitmap))
2557 n++;
2558 bit++;
2559 }
2560
2561 return n;
2562}
2563
2564/*
2565 * Invalidate all the blocks in the range [block..block+nr_blocks-1].
2566 */
2567int dmz_invalidate_blocks(struct dmz_metadata *zmd, struct dm_zone *zone,
2568 sector_t chunk_block, unsigned int nr_blocks)
2569{
2570 unsigned int count, bit, nr_bits;
2571 struct dmz_mblock *mblk;
2572 unsigned int n = 0;
2573
2574 dmz_zmd_debug(zmd, "=> INVALIDATE zone %u, block %llu, %u blocks",
2575 zone->id, (u64)chunk_block, nr_blocks);
2576
2577 WARN_ON(chunk_block + nr_blocks > zmd->zone_nr_blocks);
2578
2579 while (nr_blocks) {
2580 /* Get bitmap block */
2581 mblk = dmz_get_bitmap(zmd, zone, chunk_block);
2582 if (IS_ERR(mblk))
2583 return PTR_ERR(mblk);
2584
2585 /* Clear bits */
2586 bit = chunk_block & DMZ_BLOCK_MASK_BITS;
2587 nr_bits = min(nr_blocks, zmd->zone_bits_per_mblk - bit);
2588
2589 count = dmz_clear_bits((unsigned long *)mblk->data,
2590 bit, nr_bits);
2591 if (count) {
2592 dmz_dirty_mblock(zmd, mblk);
2593 n += count;
2594 }
2595 dmz_release_mblock(zmd, mblk);
2596
2597 nr_blocks -= nr_bits;
2598 chunk_block += nr_bits;
2599 }
2600
2601 if (zone->weight >= n)
2602 zone->weight -= n;
2603 else {
2604 dmz_zmd_warn(zmd, "Zone %u: weight %u should be >= %u",
2605 zone->id, zone->weight, n);
2606 zone->weight = 0;
2607 }
2608
2609 return 0;
2610}
2611
2612/*
2613 * Get a block bit value.
2614 */
2615static int dmz_test_block(struct dmz_metadata *zmd, struct dm_zone *zone,
2616 sector_t chunk_block)
2617{
2618 struct dmz_mblock *mblk;
2619 int ret;
2620
2621 WARN_ON(chunk_block >= zmd->zone_nr_blocks);
2622
2623 /* Get bitmap block */
2624 mblk = dmz_get_bitmap(zmd, zone, chunk_block);
2625 if (IS_ERR(mblk))
2626 return PTR_ERR(mblk);
2627
2628 /* Get offset */
2629 ret = test_bit(chunk_block & DMZ_BLOCK_MASK_BITS,
2630 (unsigned long *) mblk->data) != 0;
2631
2632 dmz_release_mblock(zmd, mblk);
2633
2634 return ret;
2635}
2636
2637/*
2638 * Return the number of blocks from chunk_block to the first block with a bit
2639 * value specified by set. Search at most nr_blocks blocks from chunk_block.
2640 */
2641static int dmz_to_next_set_block(struct dmz_metadata *zmd, struct dm_zone *zone,
2642 sector_t chunk_block, unsigned int nr_blocks,
2643 int set)
2644{
2645 struct dmz_mblock *mblk;
2646 unsigned int bit, set_bit, nr_bits;
2647 unsigned int zone_bits = zmd->zone_bits_per_mblk;
2648 unsigned long *bitmap;
2649 int n = 0;
2650
2651 WARN_ON(chunk_block + nr_blocks > zmd->zone_nr_blocks);
2652
2653 while (nr_blocks) {
2654 /* Get bitmap block */
2655 mblk = dmz_get_bitmap(zmd, zone, chunk_block);
2656 if (IS_ERR(mblk))
2657 return PTR_ERR(mblk);
2658
2659 /* Get offset */
2660 bitmap = (unsigned long *) mblk->data;
2661 bit = chunk_block & DMZ_BLOCK_MASK_BITS;
2662 nr_bits = min(nr_blocks, zone_bits - bit);
2663 if (set)
2664 set_bit = find_next_bit(bitmap, zone_bits, bit);
2665 else
2666 set_bit = find_next_zero_bit(bitmap, zone_bits, bit);
2667 dmz_release_mblock(zmd, mblk);
2668
2669 n += set_bit - bit;
2670 if (set_bit < zone_bits)
2671 break;
2672
2673 nr_blocks -= nr_bits;
2674 chunk_block += nr_bits;
2675 }
2676
2677 return n;
2678}
2679
2680/*
2681 * Test if chunk_block is valid. If it is, the number of consecutive
2682 * valid blocks from chunk_block will be returned.
2683 */
2684int dmz_block_valid(struct dmz_metadata *zmd, struct dm_zone *zone,
2685 sector_t chunk_block)
2686{
2687 int valid;
2688
2689 valid = dmz_test_block(zmd, zone, chunk_block);
2690 if (valid <= 0)
2691 return valid;
2692
2693 /* The block is valid: get the number of valid blocks from block */
2694 return dmz_to_next_set_block(zmd, zone, chunk_block,
2695 zmd->zone_nr_blocks - chunk_block, 0);
2696}
2697
2698/*
2699 * Find the first valid block from @chunk_block in @zone.
2700 * If such a block is found, its number is returned using
2701 * @chunk_block and the total number of valid blocks from @chunk_block
2702 * is returned.
2703 */
2704int dmz_first_valid_block(struct dmz_metadata *zmd, struct dm_zone *zone,
2705 sector_t *chunk_block)
2706{
2707 sector_t start_block = *chunk_block;
2708 int ret;
2709
2710 ret = dmz_to_next_set_block(zmd, zone, start_block,
2711 zmd->zone_nr_blocks - start_block, 1);
2712 if (ret < 0)
2713 return ret;
2714
2715 start_block += ret;
2716 *chunk_block = start_block;
2717
2718 return dmz_to_next_set_block(zmd, zone, start_block,
2719 zmd->zone_nr_blocks - start_block, 0);
2720}
2721
2722/*
2723 * Count the number of bits set starting from bit up to bit + nr_bits - 1.
2724 */
2725static int dmz_count_bits(void *bitmap, int bit, int nr_bits)
2726{
2727 unsigned long *addr;
2728 int end = bit + nr_bits;
2729 int n = 0;
2730
2731 while (bit < end) {
2732 if (((bit & (BITS_PER_LONG - 1)) == 0) &&
2733 ((end - bit) >= BITS_PER_LONG)) {
2734 addr = (unsigned long *)bitmap + BIT_WORD(bit);
2735 if (*addr == ULONG_MAX) {
2736 n += BITS_PER_LONG;
2737 bit += BITS_PER_LONG;
2738 continue;
2739 }
2740 }
2741
2742 if (test_bit(bit, bitmap))
2743 n++;
2744 bit++;
2745 }
2746
2747 return n;
2748}
2749
2750/*
2751 * Get a zone weight.
2752 */
2753static void dmz_get_zone_weight(struct dmz_metadata *zmd, struct dm_zone *zone)
2754{
2755 struct dmz_mblock *mblk;
2756 sector_t chunk_block = 0;
2757 unsigned int bit, nr_bits;
2758 unsigned int nr_blocks = zmd->zone_nr_blocks;
2759 void *bitmap;
2760 int n = 0;
2761
2762 while (nr_blocks) {
2763 /* Get bitmap block */
2764 mblk = dmz_get_bitmap(zmd, zone, chunk_block);
2765 if (IS_ERR(mblk)) {
2766 n = 0;
2767 break;
2768 }
2769
2770 /* Count bits in this block */
2771 bitmap = mblk->data;
2772 bit = chunk_block & DMZ_BLOCK_MASK_BITS;
2773 nr_bits = min(nr_blocks, zmd->zone_bits_per_mblk - bit);
2774 n += dmz_count_bits(bitmap, bit, nr_bits);
2775
2776 dmz_release_mblock(zmd, mblk);
2777
2778 nr_blocks -= nr_bits;
2779 chunk_block += nr_bits;
2780 }
2781
2782 zone->weight = n;
2783}
2784
2785/*
2786 * Cleanup the zoned metadata resources.
2787 */
2788static void dmz_cleanup_metadata(struct dmz_metadata *zmd)
2789{
2790 struct rb_root *root;
2791 struct dmz_mblock *mblk, *next;
2792 int i;
2793
2794 /* Release zone mapping resources */
2795 if (zmd->map_mblk) {
2796 for (i = 0; i < zmd->nr_map_blocks; i++)
2797 dmz_release_mblock(zmd, zmd->map_mblk[i]);
2798 kfree(zmd->map_mblk);
2799 zmd->map_mblk = NULL;
2800 }
2801
2802 /* Release super blocks */
2803 for (i = 0; i < 2; i++) {
2804 if (zmd->sb[i].mblk) {
2805 dmz_free_mblock(zmd, zmd->sb[i].mblk);
2806 zmd->sb[i].mblk = NULL;
2807 }
2808 }
2809
2810 /* Free cached blocks */
2811 while (!list_empty(&zmd->mblk_dirty_list)) {
2812 mblk = list_first_entry(&zmd->mblk_dirty_list,
2813 struct dmz_mblock, link);
2814 dmz_zmd_warn(zmd, "mblock %llu still in dirty list (ref %u)",
2815 (u64)mblk->no, mblk->ref);
2816 list_del_init(&mblk->link);
2817 rb_erase(&mblk->node, &zmd->mblk_rbtree);
2818 dmz_free_mblock(zmd, mblk);
2819 }
2820
2821 while (!list_empty(&zmd->mblk_lru_list)) {
2822 mblk = list_first_entry(&zmd->mblk_lru_list,
2823 struct dmz_mblock, link);
2824 list_del_init(&mblk->link);
2825 rb_erase(&mblk->node, &zmd->mblk_rbtree);
2826 dmz_free_mblock(zmd, mblk);
2827 }
2828
2829 /* Sanity checks: the mblock rbtree should now be empty */
2830 root = &zmd->mblk_rbtree;
2831 rbtree_postorder_for_each_entry_safe(mblk, next, root, node) {
2832 dmz_zmd_warn(zmd, "mblock %llu ref %u still in rbtree",
2833 (u64)mblk->no, mblk->ref);
2834 mblk->ref = 0;
2835 dmz_free_mblock(zmd, mblk);
2836 }
2837
2838 /* Free the zone descriptors */
2839 dmz_drop_zones(zmd);
2840
2841 mutex_destroy(&zmd->mblk_flush_lock);
2842 mutex_destroy(&zmd->map_lock);
2843}
2844
2845static void dmz_print_dev(struct dmz_metadata *zmd, int num)
2846{
2847 struct dmz_dev *dev = &zmd->dev[num];
2848
2849 if (bdev_zoned_model(dev->bdev) == BLK_ZONED_NONE)
2850 dmz_dev_info(dev, "Regular block device");
2851 else
2852 dmz_dev_info(dev, "Host-%s zoned block device",
2853 bdev_zoned_model(dev->bdev) == BLK_ZONED_HA ?
2854 "aware" : "managed");
2855 if (zmd->sb_version > 1) {
2856 sector_t sector_offset =
2857 dev->zone_offset << zmd->zone_nr_sectors_shift;
2858
2859 dmz_dev_info(dev, " %llu 512-byte logical sectors (offset %llu)",
2860 (u64)dev->capacity, (u64)sector_offset);
2861 dmz_dev_info(dev, " %u zones of %llu 512-byte logical sectors (offset %llu)",
2862 dev->nr_zones, (u64)zmd->zone_nr_sectors,
2863 (u64)dev->zone_offset);
2864 } else {
2865 dmz_dev_info(dev, " %llu 512-byte logical sectors",
2866 (u64)dev->capacity);
2867 dmz_dev_info(dev, " %u zones of %llu 512-byte logical sectors",
2868 dev->nr_zones, (u64)zmd->zone_nr_sectors);
2869 }
2870}
2871
2872/*
2873 * Initialize the zoned metadata.
2874 */
2875int dmz_ctr_metadata(struct dmz_dev *dev, int num_dev,
2876 struct dmz_metadata **metadata,
2877 const char *devname)
2878{
2879 struct dmz_metadata *zmd;
2880 unsigned int i;
2881 struct dm_zone *zone;
2882 int ret;
2883
2884 zmd = kzalloc(sizeof(struct dmz_metadata), GFP_KERNEL);
2885 if (!zmd)
2886 return -ENOMEM;
2887
2888 strcpy(zmd->devname, devname);
2889 zmd->dev = dev;
2890 zmd->nr_devs = num_dev;
2891 zmd->mblk_rbtree = RB_ROOT;
2892 init_rwsem(&zmd->mblk_sem);
2893 mutex_init(&zmd->mblk_flush_lock);
2894 spin_lock_init(&zmd->mblk_lock);
2895 INIT_LIST_HEAD(&zmd->mblk_lru_list);
2896 INIT_LIST_HEAD(&zmd->mblk_dirty_list);
2897
2898 mutex_init(&zmd->map_lock);
2899
2900 atomic_set(&zmd->unmap_nr_cache, 0);
2901 INIT_LIST_HEAD(&zmd->unmap_cache_list);
2902 INIT_LIST_HEAD(&zmd->map_cache_list);
2903
2904 atomic_set(&zmd->nr_reserved_seq_zones, 0);
2905 INIT_LIST_HEAD(&zmd->reserved_seq_zones_list);
2906
2907 init_waitqueue_head(&zmd->free_wq);
2908
2909 /* Initialize zone descriptors */
2910 ret = dmz_init_zones(zmd);
2911 if (ret)
2912 goto err;
2913
2914 /* Get super block */
2915 ret = dmz_load_sb(zmd);
2916 if (ret)
2917 goto err;
2918
2919 /* Set metadata zones starting from sb_zone */
2920 for (i = 0; i < zmd->nr_meta_zones << 1; i++) {
2921 zone = dmz_get(zmd, zmd->sb[0].zone->id + i);
2922 if (!zone) {
2923 dmz_zmd_err(zmd,
2924 "metadata zone %u not present", i);
2925 ret = -ENXIO;
2926 goto err;
2927 }
2928 if (!dmz_is_rnd(zone) && !dmz_is_cache(zone)) {
2929 dmz_zmd_err(zmd,
2930 "metadata zone %d is not random", i);
2931 ret = -ENXIO;
2932 goto err;
2933 }
2934 set_bit(DMZ_META, &zone->flags);
2935 }
2936 /* Load mapping table */
2937 ret = dmz_load_mapping(zmd);
2938 if (ret)
2939 goto err;
2940
2941 /*
2942 * Cache size boundaries: allow at least 2 super blocks, the chunk map
2943 * blocks and enough blocks to be able to cache the bitmap blocks of
2944 * up to 16 zones when idle (min_nr_mblks). Otherwise, if busy, allow
2945 * the cache to add 512 more metadata blocks.
2946 */
2947 zmd->min_nr_mblks = 2 + zmd->nr_map_blocks + zmd->zone_nr_bitmap_blocks * 16;
2948 zmd->max_nr_mblks = zmd->min_nr_mblks + 512;
2949 zmd->mblk_shrinker.count_objects = dmz_mblock_shrinker_count;
2950 zmd->mblk_shrinker.scan_objects = dmz_mblock_shrinker_scan;
2951 zmd->mblk_shrinker.seeks = DEFAULT_SEEKS;
2952
2953 /* Metadata cache shrinker */
2954 ret = register_shrinker(&zmd->mblk_shrinker);
2955 if (ret) {
2956 dmz_zmd_err(zmd, "Register metadata cache shrinker failed");
2957 goto err;
2958 }
2959
2960 dmz_zmd_info(zmd, "DM-Zoned metadata version %d", zmd->sb_version);
2961 for (i = 0; i < zmd->nr_devs; i++)
2962 dmz_print_dev(zmd, i);
2963
2964 dmz_zmd_info(zmd, " %u zones of %llu 512-byte logical sectors",
2965 zmd->nr_zones, (u64)zmd->zone_nr_sectors);
2966 dmz_zmd_debug(zmd, " %u metadata zones",
2967 zmd->nr_meta_zones * 2);
2968 dmz_zmd_debug(zmd, " %u data zones for %u chunks",
2969 zmd->nr_data_zones, zmd->nr_chunks);
2970 dmz_zmd_debug(zmd, " %u cache zones (%u unmapped)",
2971 zmd->nr_cache, atomic_read(&zmd->unmap_nr_cache));
2972 for (i = 0; i < zmd->nr_devs; i++) {
2973 dmz_zmd_debug(zmd, " %u random zones (%u unmapped)",
2974 dmz_nr_rnd_zones(zmd, i),
2975 dmz_nr_unmap_rnd_zones(zmd, i));
2976 dmz_zmd_debug(zmd, " %u sequential zones (%u unmapped)",
2977 dmz_nr_seq_zones(zmd, i),
2978 dmz_nr_unmap_seq_zones(zmd, i));
2979 }
2980 dmz_zmd_debug(zmd, " %u reserved sequential data zones",
2981 zmd->nr_reserved_seq);
2982 dmz_zmd_debug(zmd, "Format:");
2983 dmz_zmd_debug(zmd, "%u metadata blocks per set (%u max cache)",
2984 zmd->nr_meta_blocks, zmd->max_nr_mblks);
2985 dmz_zmd_debug(zmd, " %u data zone mapping blocks",
2986 zmd->nr_map_blocks);
2987 dmz_zmd_debug(zmd, " %u bitmap blocks",
2988 zmd->nr_bitmap_blocks);
2989
2990 *metadata = zmd;
2991
2992 return 0;
2993err:
2994 dmz_cleanup_metadata(zmd);
2995 kfree(zmd);
2996 *metadata = NULL;
2997
2998 return ret;
2999}
3000
3001/*
3002 * Cleanup the zoned metadata resources.
3003 */
3004void dmz_dtr_metadata(struct dmz_metadata *zmd)
3005{
3006 unregister_shrinker(&zmd->mblk_shrinker);
3007 dmz_cleanup_metadata(zmd);
3008 kfree(zmd);
3009}
3010
3011/*
3012 * Check zone information on resume.
3013 */
3014int dmz_resume_metadata(struct dmz_metadata *zmd)
3015{
3016 struct dm_zone *zone;
3017 sector_t wp_block;
3018 unsigned int i;
3019 int ret;
3020
3021 /* Check zones */
3022 for (i = 0; i < zmd->nr_zones; i++) {
3023 zone = dmz_get(zmd, i);
3024 if (!zone) {
3025 dmz_zmd_err(zmd, "Unable to get zone %u", i);
3026 return -EIO;
3027 }
3028 wp_block = zone->wp_block;
3029
3030 ret = dmz_update_zone(zmd, zone);
3031 if (ret) {
3032 dmz_zmd_err(zmd, "Broken zone %u", i);
3033 return ret;
3034 }
3035
3036 if (dmz_is_offline(zone)) {
3037 dmz_zmd_warn(zmd, "Zone %u is offline", i);
3038 continue;
3039 }
3040
3041 /* Check write pointer */
3042 if (!dmz_is_seq(zone))
3043 zone->wp_block = 0;
3044 else if (zone->wp_block != wp_block) {
3045 dmz_zmd_err(zmd, "Zone %u: Invalid wp (%llu / %llu)",
3046 i, (u64)zone->wp_block, (u64)wp_block);
3047 zone->wp_block = wp_block;
3048 dmz_invalidate_blocks(zmd, zone, zone->wp_block,
3049 zmd->zone_nr_blocks - zone->wp_block);
3050 }
3051 }
3052
3053 return 0;
3054}
1/*
2 * Copyright (C) 2017 Western Digital Corporation or its affiliates.
3 *
4 * This file is released under the GPL.
5 */
6
7#include "dm-zoned.h"
8
9#include <linux/module.h>
10#include <linux/crc32.h>
11
12#define DM_MSG_PREFIX "zoned metadata"
13
14/*
15 * Metadata version.
16 */
17#define DMZ_META_VER 1
18
19/*
20 * On-disk super block magic.
21 */
22#define DMZ_MAGIC ((((unsigned int)('D')) << 24) | \
23 (((unsigned int)('Z')) << 16) | \
24 (((unsigned int)('B')) << 8) | \
25 ((unsigned int)('D')))
26
27/*
28 * On disk super block.
29 * This uses only 512 B but uses on disk a full 4KB block. This block is
30 * followed on disk by the mapping table of chunks to zones and the bitmap
31 * blocks indicating zone block validity.
32 * The overall resulting metadata format is:
33 * (1) Super block (1 block)
34 * (2) Chunk mapping table (nr_map_blocks)
35 * (3) Bitmap blocks (nr_bitmap_blocks)
36 * All metadata blocks are stored in conventional zones, starting from the
37 * the first conventional zone found on disk.
38 */
39struct dmz_super {
40 /* Magic number */
41 __le32 magic; /* 4 */
42
43 /* Metadata version number */
44 __le32 version; /* 8 */
45
46 /* Generation number */
47 __le64 gen; /* 16 */
48
49 /* This block number */
50 __le64 sb_block; /* 24 */
51
52 /* The number of metadata blocks, including this super block */
53 __le32 nr_meta_blocks; /* 28 */
54
55 /* The number of sequential zones reserved for reclaim */
56 __le32 nr_reserved_seq; /* 32 */
57
58 /* The number of entries in the mapping table */
59 __le32 nr_chunks; /* 36 */
60
61 /* The number of blocks used for the chunk mapping table */
62 __le32 nr_map_blocks; /* 40 */
63
64 /* The number of blocks used for the block bitmaps */
65 __le32 nr_bitmap_blocks; /* 44 */
66
67 /* Checksum */
68 __le32 crc; /* 48 */
69
70 /* Padding to full 512B sector */
71 u8 reserved[464]; /* 512 */
72};
73
74/*
75 * Chunk mapping entry: entries are indexed by chunk number
76 * and give the zone ID (dzone_id) mapping the chunk on disk.
77 * This zone may be sequential or random. If it is a sequential
78 * zone, a second zone (bzone_id) used as a write buffer may
79 * also be specified. This second zone will always be a randomly
80 * writeable zone.
81 */
82struct dmz_map {
83 __le32 dzone_id;
84 __le32 bzone_id;
85};
86
87/*
88 * Chunk mapping table metadata: 512 8-bytes entries per 4KB block.
89 */
90#define DMZ_MAP_ENTRIES (DMZ_BLOCK_SIZE / sizeof(struct dmz_map))
91#define DMZ_MAP_ENTRIES_SHIFT (ilog2(DMZ_MAP_ENTRIES))
92#define DMZ_MAP_ENTRIES_MASK (DMZ_MAP_ENTRIES - 1)
93#define DMZ_MAP_UNMAPPED UINT_MAX
94
95/*
96 * Meta data block descriptor (for cached metadata blocks).
97 */
98struct dmz_mblock {
99 struct rb_node node;
100 struct list_head link;
101 sector_t no;
102 atomic_t ref;
103 unsigned long state;
104 struct page *page;
105 void *data;
106};
107
108/*
109 * Metadata block state flags.
110 */
111enum {
112 DMZ_META_DIRTY,
113 DMZ_META_READING,
114 DMZ_META_WRITING,
115 DMZ_META_ERROR,
116};
117
118/*
119 * Super block information (one per metadata set).
120 */
121struct dmz_sb {
122 sector_t block;
123 struct dmz_mblock *mblk;
124 struct dmz_super *sb;
125};
126
127/*
128 * In-memory metadata.
129 */
130struct dmz_metadata {
131 struct dmz_dev *dev;
132
133 sector_t zone_bitmap_size;
134 unsigned int zone_nr_bitmap_blocks;
135
136 unsigned int nr_bitmap_blocks;
137 unsigned int nr_map_blocks;
138
139 unsigned int nr_useable_zones;
140 unsigned int nr_meta_blocks;
141 unsigned int nr_meta_zones;
142 unsigned int nr_data_zones;
143 unsigned int nr_rnd_zones;
144 unsigned int nr_reserved_seq;
145 unsigned int nr_chunks;
146
147 /* Zone information array */
148 struct dm_zone *zones;
149
150 struct dm_zone *sb_zone;
151 struct dmz_sb sb[2];
152 unsigned int mblk_primary;
153 u64 sb_gen;
154 unsigned int min_nr_mblks;
155 unsigned int max_nr_mblks;
156 atomic_t nr_mblks;
157 struct rw_semaphore mblk_sem;
158 struct mutex mblk_flush_lock;
159 spinlock_t mblk_lock;
160 struct rb_root mblk_rbtree;
161 struct list_head mblk_lru_list;
162 struct list_head mblk_dirty_list;
163 struct shrinker mblk_shrinker;
164
165 /* Zone allocation management */
166 struct mutex map_lock;
167 struct dmz_mblock **map_mblk;
168 unsigned int nr_rnd;
169 atomic_t unmap_nr_rnd;
170 struct list_head unmap_rnd_list;
171 struct list_head map_rnd_list;
172
173 unsigned int nr_seq;
174 atomic_t unmap_nr_seq;
175 struct list_head unmap_seq_list;
176 struct list_head map_seq_list;
177
178 atomic_t nr_reserved_seq_zones;
179 struct list_head reserved_seq_zones_list;
180
181 wait_queue_head_t free_wq;
182};
183
184/*
185 * Various accessors
186 */
187unsigned int dmz_id(struct dmz_metadata *zmd, struct dm_zone *zone)
188{
189 return ((unsigned int)(zone - zmd->zones));
190}
191
192sector_t dmz_start_sect(struct dmz_metadata *zmd, struct dm_zone *zone)
193{
194 return (sector_t)dmz_id(zmd, zone) << zmd->dev->zone_nr_sectors_shift;
195}
196
197sector_t dmz_start_block(struct dmz_metadata *zmd, struct dm_zone *zone)
198{
199 return (sector_t)dmz_id(zmd, zone) << zmd->dev->zone_nr_blocks_shift;
200}
201
202unsigned int dmz_nr_chunks(struct dmz_metadata *zmd)
203{
204 return zmd->nr_chunks;
205}
206
207unsigned int dmz_nr_rnd_zones(struct dmz_metadata *zmd)
208{
209 return zmd->nr_rnd;
210}
211
212unsigned int dmz_nr_unmap_rnd_zones(struct dmz_metadata *zmd)
213{
214 return atomic_read(&zmd->unmap_nr_rnd);
215}
216
217/*
218 * Lock/unlock mapping table.
219 * The map lock also protects all the zone lists.
220 */
221void dmz_lock_map(struct dmz_metadata *zmd)
222{
223 mutex_lock(&zmd->map_lock);
224}
225
226void dmz_unlock_map(struct dmz_metadata *zmd)
227{
228 mutex_unlock(&zmd->map_lock);
229}
230
231/*
232 * Lock/unlock metadata access. This is a "read" lock on a semaphore
233 * that prevents metadata flush from running while metadata are being
234 * modified. The actual metadata write mutual exclusion is achieved with
235 * the map lock and zone styate management (active and reclaim state are
236 * mutually exclusive).
237 */
238void dmz_lock_metadata(struct dmz_metadata *zmd)
239{
240 down_read(&zmd->mblk_sem);
241}
242
243void dmz_unlock_metadata(struct dmz_metadata *zmd)
244{
245 up_read(&zmd->mblk_sem);
246}
247
248/*
249 * Lock/unlock flush: prevent concurrent executions
250 * of dmz_flush_metadata as well as metadata modification in reclaim
251 * while flush is being executed.
252 */
253void dmz_lock_flush(struct dmz_metadata *zmd)
254{
255 mutex_lock(&zmd->mblk_flush_lock);
256}
257
258void dmz_unlock_flush(struct dmz_metadata *zmd)
259{
260 mutex_unlock(&zmd->mblk_flush_lock);
261}
262
263/*
264 * Allocate a metadata block.
265 */
266static struct dmz_mblock *dmz_alloc_mblock(struct dmz_metadata *zmd,
267 sector_t mblk_no)
268{
269 struct dmz_mblock *mblk = NULL;
270
271 /* See if we can reuse cached blocks */
272 if (zmd->max_nr_mblks && atomic_read(&zmd->nr_mblks) > zmd->max_nr_mblks) {
273 spin_lock(&zmd->mblk_lock);
274 mblk = list_first_entry_or_null(&zmd->mblk_lru_list,
275 struct dmz_mblock, link);
276 if (mblk) {
277 list_del_init(&mblk->link);
278 rb_erase(&mblk->node, &zmd->mblk_rbtree);
279 mblk->no = mblk_no;
280 }
281 spin_unlock(&zmd->mblk_lock);
282 if (mblk)
283 return mblk;
284 }
285
286 /* Allocate a new block */
287 mblk = kmalloc(sizeof(struct dmz_mblock), GFP_NOIO);
288 if (!mblk)
289 return NULL;
290
291 mblk->page = alloc_page(GFP_NOIO);
292 if (!mblk->page) {
293 kfree(mblk);
294 return NULL;
295 }
296
297 RB_CLEAR_NODE(&mblk->node);
298 INIT_LIST_HEAD(&mblk->link);
299 atomic_set(&mblk->ref, 0);
300 mblk->state = 0;
301 mblk->no = mblk_no;
302 mblk->data = page_address(mblk->page);
303
304 atomic_inc(&zmd->nr_mblks);
305
306 return mblk;
307}
308
309/*
310 * Free a metadata block.
311 */
312static void dmz_free_mblock(struct dmz_metadata *zmd, struct dmz_mblock *mblk)
313{
314 __free_pages(mblk->page, 0);
315 kfree(mblk);
316
317 atomic_dec(&zmd->nr_mblks);
318}
319
320/*
321 * Insert a metadata block in the rbtree.
322 */
323static void dmz_insert_mblock(struct dmz_metadata *zmd, struct dmz_mblock *mblk)
324{
325 struct rb_root *root = &zmd->mblk_rbtree;
326 struct rb_node **new = &(root->rb_node), *parent = NULL;
327 struct dmz_mblock *b;
328
329 /* Figure out where to put the new node */
330 while (*new) {
331 b = container_of(*new, struct dmz_mblock, node);
332 parent = *new;
333 new = (b->no < mblk->no) ? &((*new)->rb_left) : &((*new)->rb_right);
334 }
335
336 /* Add new node and rebalance tree */
337 rb_link_node(&mblk->node, parent, new);
338 rb_insert_color(&mblk->node, root);
339}
340
341/*
342 * Lookup a metadata block in the rbtree.
343 */
344static struct dmz_mblock *dmz_lookup_mblock(struct dmz_metadata *zmd,
345 sector_t mblk_no)
346{
347 struct rb_root *root = &zmd->mblk_rbtree;
348 struct rb_node *node = root->rb_node;
349 struct dmz_mblock *mblk;
350
351 while (node) {
352 mblk = container_of(node, struct dmz_mblock, node);
353 if (mblk->no == mblk_no)
354 return mblk;
355 node = (mblk->no < mblk_no) ? node->rb_left : node->rb_right;
356 }
357
358 return NULL;
359}
360
361/*
362 * Metadata block BIO end callback.
363 */
364static void dmz_mblock_bio_end_io(struct bio *bio)
365{
366 struct dmz_mblock *mblk = bio->bi_private;
367 int flag;
368
369 if (bio->bi_status)
370 set_bit(DMZ_META_ERROR, &mblk->state);
371
372 if (bio_op(bio) == REQ_OP_WRITE)
373 flag = DMZ_META_WRITING;
374 else
375 flag = DMZ_META_READING;
376
377 clear_bit_unlock(flag, &mblk->state);
378 smp_mb__after_atomic();
379 wake_up_bit(&mblk->state, flag);
380
381 bio_put(bio);
382}
383
384/*
385 * Read a metadata block from disk.
386 */
387static struct dmz_mblock *dmz_fetch_mblock(struct dmz_metadata *zmd,
388 sector_t mblk_no)
389{
390 struct dmz_mblock *mblk;
391 sector_t block = zmd->sb[zmd->mblk_primary].block + mblk_no;
392 struct bio *bio;
393
394 /* Get block and insert it */
395 mblk = dmz_alloc_mblock(zmd, mblk_no);
396 if (!mblk)
397 return NULL;
398
399 spin_lock(&zmd->mblk_lock);
400 atomic_inc(&mblk->ref);
401 set_bit(DMZ_META_READING, &mblk->state);
402 dmz_insert_mblock(zmd, mblk);
403 spin_unlock(&zmd->mblk_lock);
404
405 bio = bio_alloc(GFP_NOIO, 1);
406 if (!bio) {
407 dmz_free_mblock(zmd, mblk);
408 return NULL;
409 }
410
411 bio->bi_iter.bi_sector = dmz_blk2sect(block);
412 bio_set_dev(bio, zmd->dev->bdev);
413 bio->bi_private = mblk;
414 bio->bi_end_io = dmz_mblock_bio_end_io;
415 bio_set_op_attrs(bio, REQ_OP_READ, REQ_META | REQ_PRIO);
416 bio_add_page(bio, mblk->page, DMZ_BLOCK_SIZE, 0);
417 submit_bio(bio);
418
419 return mblk;
420}
421
422/*
423 * Free metadata blocks.
424 */
425static unsigned long dmz_shrink_mblock_cache(struct dmz_metadata *zmd,
426 unsigned long limit)
427{
428 struct dmz_mblock *mblk;
429 unsigned long count = 0;
430
431 if (!zmd->max_nr_mblks)
432 return 0;
433
434 while (!list_empty(&zmd->mblk_lru_list) &&
435 atomic_read(&zmd->nr_mblks) > zmd->min_nr_mblks &&
436 count < limit) {
437 mblk = list_first_entry(&zmd->mblk_lru_list,
438 struct dmz_mblock, link);
439 list_del_init(&mblk->link);
440 rb_erase(&mblk->node, &zmd->mblk_rbtree);
441 dmz_free_mblock(zmd, mblk);
442 count++;
443 }
444
445 return count;
446}
447
448/*
449 * For mblock shrinker: get the number of unused metadata blocks in the cache.
450 */
451static unsigned long dmz_mblock_shrinker_count(struct shrinker *shrink,
452 struct shrink_control *sc)
453{
454 struct dmz_metadata *zmd = container_of(shrink, struct dmz_metadata, mblk_shrinker);
455
456 return atomic_read(&zmd->nr_mblks);
457}
458
459/*
460 * For mblock shrinker: scan unused metadata blocks and shrink the cache.
461 */
462static unsigned long dmz_mblock_shrinker_scan(struct shrinker *shrink,
463 struct shrink_control *sc)
464{
465 struct dmz_metadata *zmd = container_of(shrink, struct dmz_metadata, mblk_shrinker);
466 unsigned long count;
467
468 spin_lock(&zmd->mblk_lock);
469 count = dmz_shrink_mblock_cache(zmd, sc->nr_to_scan);
470 spin_unlock(&zmd->mblk_lock);
471
472 return count ? count : SHRINK_STOP;
473}
474
475/*
476 * Release a metadata block.
477 */
478static void dmz_release_mblock(struct dmz_metadata *zmd,
479 struct dmz_mblock *mblk)
480{
481
482 if (!mblk)
483 return;
484
485 spin_lock(&zmd->mblk_lock);
486
487 if (atomic_dec_and_test(&mblk->ref)) {
488 if (test_bit(DMZ_META_ERROR, &mblk->state)) {
489 rb_erase(&mblk->node, &zmd->mblk_rbtree);
490 dmz_free_mblock(zmd, mblk);
491 } else if (!test_bit(DMZ_META_DIRTY, &mblk->state)) {
492 list_add_tail(&mblk->link, &zmd->mblk_lru_list);
493 dmz_shrink_mblock_cache(zmd, 1);
494 }
495 }
496
497 spin_unlock(&zmd->mblk_lock);
498}
499
500/*
501 * Get a metadata block from the rbtree. If the block
502 * is not present, read it from disk.
503 */
504static struct dmz_mblock *dmz_get_mblock(struct dmz_metadata *zmd,
505 sector_t mblk_no)
506{
507 struct dmz_mblock *mblk;
508
509 /* Check rbtree */
510 spin_lock(&zmd->mblk_lock);
511 mblk = dmz_lookup_mblock(zmd, mblk_no);
512 if (mblk) {
513 /* Cache hit: remove block from LRU list */
514 if (atomic_inc_return(&mblk->ref) == 1 &&
515 !test_bit(DMZ_META_DIRTY, &mblk->state))
516 list_del_init(&mblk->link);
517 }
518 spin_unlock(&zmd->mblk_lock);
519
520 if (!mblk) {
521 /* Cache miss: read the block from disk */
522 mblk = dmz_fetch_mblock(zmd, mblk_no);
523 if (!mblk)
524 return ERR_PTR(-ENOMEM);
525 }
526
527 /* Wait for on-going read I/O and check for error */
528 wait_on_bit_io(&mblk->state, DMZ_META_READING,
529 TASK_UNINTERRUPTIBLE);
530 if (test_bit(DMZ_META_ERROR, &mblk->state)) {
531 dmz_release_mblock(zmd, mblk);
532 return ERR_PTR(-EIO);
533 }
534
535 return mblk;
536}
537
538/*
539 * Mark a metadata block dirty.
540 */
541static void dmz_dirty_mblock(struct dmz_metadata *zmd, struct dmz_mblock *mblk)
542{
543 spin_lock(&zmd->mblk_lock);
544 if (!test_and_set_bit(DMZ_META_DIRTY, &mblk->state))
545 list_add_tail(&mblk->link, &zmd->mblk_dirty_list);
546 spin_unlock(&zmd->mblk_lock);
547}
548
549/*
550 * Issue a metadata block write BIO.
551 */
552static void dmz_write_mblock(struct dmz_metadata *zmd, struct dmz_mblock *mblk,
553 unsigned int set)
554{
555 sector_t block = zmd->sb[set].block + mblk->no;
556 struct bio *bio;
557
558 bio = bio_alloc(GFP_NOIO, 1);
559 if (!bio) {
560 set_bit(DMZ_META_ERROR, &mblk->state);
561 return;
562 }
563
564 set_bit(DMZ_META_WRITING, &mblk->state);
565
566 bio->bi_iter.bi_sector = dmz_blk2sect(block);
567 bio_set_dev(bio, zmd->dev->bdev);
568 bio->bi_private = mblk;
569 bio->bi_end_io = dmz_mblock_bio_end_io;
570 bio_set_op_attrs(bio, REQ_OP_WRITE, REQ_META | REQ_PRIO);
571 bio_add_page(bio, mblk->page, DMZ_BLOCK_SIZE, 0);
572 submit_bio(bio);
573}
574
575/*
576 * Read/write a metadata block.
577 */
578static int dmz_rdwr_block(struct dmz_metadata *zmd, int op, sector_t block,
579 struct page *page)
580{
581 struct bio *bio;
582 int ret;
583
584 bio = bio_alloc(GFP_NOIO, 1);
585 if (!bio)
586 return -ENOMEM;
587
588 bio->bi_iter.bi_sector = dmz_blk2sect(block);
589 bio_set_dev(bio, zmd->dev->bdev);
590 bio_set_op_attrs(bio, op, REQ_SYNC | REQ_META | REQ_PRIO);
591 bio_add_page(bio, page, DMZ_BLOCK_SIZE, 0);
592 ret = submit_bio_wait(bio);
593 bio_put(bio);
594
595 return ret;
596}
597
598/*
599 * Write super block of the specified metadata set.
600 */
601static int dmz_write_sb(struct dmz_metadata *zmd, unsigned int set)
602{
603 sector_t block = zmd->sb[set].block;
604 struct dmz_mblock *mblk = zmd->sb[set].mblk;
605 struct dmz_super *sb = zmd->sb[set].sb;
606 u64 sb_gen = zmd->sb_gen + 1;
607 int ret;
608
609 sb->magic = cpu_to_le32(DMZ_MAGIC);
610 sb->version = cpu_to_le32(DMZ_META_VER);
611
612 sb->gen = cpu_to_le64(sb_gen);
613
614 sb->sb_block = cpu_to_le64(block);
615 sb->nr_meta_blocks = cpu_to_le32(zmd->nr_meta_blocks);
616 sb->nr_reserved_seq = cpu_to_le32(zmd->nr_reserved_seq);
617 sb->nr_chunks = cpu_to_le32(zmd->nr_chunks);
618
619 sb->nr_map_blocks = cpu_to_le32(zmd->nr_map_blocks);
620 sb->nr_bitmap_blocks = cpu_to_le32(zmd->nr_bitmap_blocks);
621
622 sb->crc = 0;
623 sb->crc = cpu_to_le32(crc32_le(sb_gen, (unsigned char *)sb, DMZ_BLOCK_SIZE));
624
625 ret = dmz_rdwr_block(zmd, REQ_OP_WRITE, block, mblk->page);
626 if (ret == 0)
627 ret = blkdev_issue_flush(zmd->dev->bdev, GFP_NOIO, NULL);
628
629 return ret;
630}
631
632/*
633 * Write dirty metadata blocks to the specified set.
634 */
635static int dmz_write_dirty_mblocks(struct dmz_metadata *zmd,
636 struct list_head *write_list,
637 unsigned int set)
638{
639 struct dmz_mblock *mblk;
640 struct blk_plug plug;
641 int ret = 0;
642
643 /* Issue writes */
644 blk_start_plug(&plug);
645 list_for_each_entry(mblk, write_list, link)
646 dmz_write_mblock(zmd, mblk, set);
647 blk_finish_plug(&plug);
648
649 /* Wait for completion */
650 list_for_each_entry(mblk, write_list, link) {
651 wait_on_bit_io(&mblk->state, DMZ_META_WRITING,
652 TASK_UNINTERRUPTIBLE);
653 if (test_bit(DMZ_META_ERROR, &mblk->state)) {
654 clear_bit(DMZ_META_ERROR, &mblk->state);
655 ret = -EIO;
656 }
657 }
658
659 /* Flush drive cache (this will also sync data) */
660 if (ret == 0)
661 ret = blkdev_issue_flush(zmd->dev->bdev, GFP_NOIO, NULL);
662
663 return ret;
664}
665
666/*
667 * Log dirty metadata blocks.
668 */
669static int dmz_log_dirty_mblocks(struct dmz_metadata *zmd,
670 struct list_head *write_list)
671{
672 unsigned int log_set = zmd->mblk_primary ^ 0x1;
673 int ret;
674
675 /* Write dirty blocks to the log */
676 ret = dmz_write_dirty_mblocks(zmd, write_list, log_set);
677 if (ret)
678 return ret;
679
680 /*
681 * No error so far: now validate the log by updating the
682 * log index super block generation.
683 */
684 ret = dmz_write_sb(zmd, log_set);
685 if (ret)
686 return ret;
687
688 return 0;
689}
690
691/*
692 * Flush dirty metadata blocks.
693 */
694int dmz_flush_metadata(struct dmz_metadata *zmd)
695{
696 struct dmz_mblock *mblk;
697 struct list_head write_list;
698 int ret;
699
700 if (WARN_ON(!zmd))
701 return 0;
702
703 INIT_LIST_HEAD(&write_list);
704
705 /*
706 * Make sure that metadata blocks are stable before logging: take
707 * the write lock on the metadata semaphore to prevent target BIOs
708 * from modifying metadata.
709 */
710 down_write(&zmd->mblk_sem);
711
712 /*
713 * This is called from the target flush work and reclaim work.
714 * Concurrent execution is not allowed.
715 */
716 dmz_lock_flush(zmd);
717
718 /* Get dirty blocks */
719 spin_lock(&zmd->mblk_lock);
720 list_splice_init(&zmd->mblk_dirty_list, &write_list);
721 spin_unlock(&zmd->mblk_lock);
722
723 /* If there are no dirty metadata blocks, just flush the device cache */
724 if (list_empty(&write_list)) {
725 ret = blkdev_issue_flush(zmd->dev->bdev, GFP_NOIO, NULL);
726 goto out;
727 }
728
729 /*
730 * The primary metadata set is still clean. Keep it this way until
731 * all updates are successful in the secondary set. That is, use
732 * the secondary set as a log.
733 */
734 ret = dmz_log_dirty_mblocks(zmd, &write_list);
735 if (ret)
736 goto out;
737
738 /*
739 * The log is on disk. It is now safe to update in place
740 * in the primary metadata set.
741 */
742 ret = dmz_write_dirty_mblocks(zmd, &write_list, zmd->mblk_primary);
743 if (ret)
744 goto out;
745
746 ret = dmz_write_sb(zmd, zmd->mblk_primary);
747 if (ret)
748 goto out;
749
750 while (!list_empty(&write_list)) {
751 mblk = list_first_entry(&write_list, struct dmz_mblock, link);
752 list_del_init(&mblk->link);
753
754 spin_lock(&zmd->mblk_lock);
755 clear_bit(DMZ_META_DIRTY, &mblk->state);
756 if (atomic_read(&mblk->ref) == 0)
757 list_add_tail(&mblk->link, &zmd->mblk_lru_list);
758 spin_unlock(&zmd->mblk_lock);
759 }
760
761 zmd->sb_gen++;
762out:
763 if (ret && !list_empty(&write_list)) {
764 spin_lock(&zmd->mblk_lock);
765 list_splice(&write_list, &zmd->mblk_dirty_list);
766 spin_unlock(&zmd->mblk_lock);
767 }
768
769 dmz_unlock_flush(zmd);
770 up_write(&zmd->mblk_sem);
771
772 return ret;
773}
774
775/*
776 * Check super block.
777 */
778static int dmz_check_sb(struct dmz_metadata *zmd, struct dmz_super *sb)
779{
780 unsigned int nr_meta_zones, nr_data_zones;
781 struct dmz_dev *dev = zmd->dev;
782 u32 crc, stored_crc;
783 u64 gen;
784
785 gen = le64_to_cpu(sb->gen);
786 stored_crc = le32_to_cpu(sb->crc);
787 sb->crc = 0;
788 crc = crc32_le(gen, (unsigned char *)sb, DMZ_BLOCK_SIZE);
789 if (crc != stored_crc) {
790 dmz_dev_err(dev, "Invalid checksum (needed 0x%08x, got 0x%08x)",
791 crc, stored_crc);
792 return -ENXIO;
793 }
794
795 if (le32_to_cpu(sb->magic) != DMZ_MAGIC) {
796 dmz_dev_err(dev, "Invalid meta magic (needed 0x%08x, got 0x%08x)",
797 DMZ_MAGIC, le32_to_cpu(sb->magic));
798 return -ENXIO;
799 }
800
801 if (le32_to_cpu(sb->version) != DMZ_META_VER) {
802 dmz_dev_err(dev, "Invalid meta version (needed %d, got %d)",
803 DMZ_META_VER, le32_to_cpu(sb->version));
804 return -ENXIO;
805 }
806
807 nr_meta_zones = (le32_to_cpu(sb->nr_meta_blocks) + dev->zone_nr_blocks - 1)
808 >> dev->zone_nr_blocks_shift;
809 if (!nr_meta_zones ||
810 nr_meta_zones >= zmd->nr_rnd_zones) {
811 dmz_dev_err(dev, "Invalid number of metadata blocks");
812 return -ENXIO;
813 }
814
815 if (!le32_to_cpu(sb->nr_reserved_seq) ||
816 le32_to_cpu(sb->nr_reserved_seq) >= (zmd->nr_useable_zones - nr_meta_zones)) {
817 dmz_dev_err(dev, "Invalid number of reserved sequential zones");
818 return -ENXIO;
819 }
820
821 nr_data_zones = zmd->nr_useable_zones -
822 (nr_meta_zones * 2 + le32_to_cpu(sb->nr_reserved_seq));
823 if (le32_to_cpu(sb->nr_chunks) > nr_data_zones) {
824 dmz_dev_err(dev, "Invalid number of chunks %u / %u",
825 le32_to_cpu(sb->nr_chunks), nr_data_zones);
826 return -ENXIO;
827 }
828
829 /* OK */
830 zmd->nr_meta_blocks = le32_to_cpu(sb->nr_meta_blocks);
831 zmd->nr_reserved_seq = le32_to_cpu(sb->nr_reserved_seq);
832 zmd->nr_chunks = le32_to_cpu(sb->nr_chunks);
833 zmd->nr_map_blocks = le32_to_cpu(sb->nr_map_blocks);
834 zmd->nr_bitmap_blocks = le32_to_cpu(sb->nr_bitmap_blocks);
835 zmd->nr_meta_zones = nr_meta_zones;
836 zmd->nr_data_zones = nr_data_zones;
837
838 return 0;
839}
840
841/*
842 * Read the first or second super block from disk.
843 */
844static int dmz_read_sb(struct dmz_metadata *zmd, unsigned int set)
845{
846 return dmz_rdwr_block(zmd, REQ_OP_READ, zmd->sb[set].block,
847 zmd->sb[set].mblk->page);
848}
849
850/*
851 * Determine the position of the secondary super blocks on disk.
852 * This is used only if a corruption of the primary super block
853 * is detected.
854 */
855static int dmz_lookup_secondary_sb(struct dmz_metadata *zmd)
856{
857 unsigned int zone_nr_blocks = zmd->dev->zone_nr_blocks;
858 struct dmz_mblock *mblk;
859 int i;
860
861 /* Allocate a block */
862 mblk = dmz_alloc_mblock(zmd, 0);
863 if (!mblk)
864 return -ENOMEM;
865
866 zmd->sb[1].mblk = mblk;
867 zmd->sb[1].sb = mblk->data;
868
869 /* Bad first super block: search for the second one */
870 zmd->sb[1].block = zmd->sb[0].block + zone_nr_blocks;
871 for (i = 0; i < zmd->nr_rnd_zones - 1; i++) {
872 if (dmz_read_sb(zmd, 1) != 0)
873 break;
874 if (le32_to_cpu(zmd->sb[1].sb->magic) == DMZ_MAGIC)
875 return 0;
876 zmd->sb[1].block += zone_nr_blocks;
877 }
878
879 dmz_free_mblock(zmd, mblk);
880 zmd->sb[1].mblk = NULL;
881
882 return -EIO;
883}
884
885/*
886 * Read the first or second super block from disk.
887 */
888static int dmz_get_sb(struct dmz_metadata *zmd, unsigned int set)
889{
890 struct dmz_mblock *mblk;
891 int ret;
892
893 /* Allocate a block */
894 mblk = dmz_alloc_mblock(zmd, 0);
895 if (!mblk)
896 return -ENOMEM;
897
898 zmd->sb[set].mblk = mblk;
899 zmd->sb[set].sb = mblk->data;
900
901 /* Read super block */
902 ret = dmz_read_sb(zmd, set);
903 if (ret) {
904 dmz_free_mblock(zmd, mblk);
905 zmd->sb[set].mblk = NULL;
906 return ret;
907 }
908
909 return 0;
910}
911
912/*
913 * Recover a metadata set.
914 */
915static int dmz_recover_mblocks(struct dmz_metadata *zmd, unsigned int dst_set)
916{
917 unsigned int src_set = dst_set ^ 0x1;
918 struct page *page;
919 int i, ret;
920
921 dmz_dev_warn(zmd->dev, "Metadata set %u invalid: recovering", dst_set);
922
923 if (dst_set == 0)
924 zmd->sb[0].block = dmz_start_block(zmd, zmd->sb_zone);
925 else {
926 zmd->sb[1].block = zmd->sb[0].block +
927 (zmd->nr_meta_zones << zmd->dev->zone_nr_blocks_shift);
928 }
929
930 page = alloc_page(GFP_NOIO);
931 if (!page)
932 return -ENOMEM;
933
934 /* Copy metadata blocks */
935 for (i = 1; i < zmd->nr_meta_blocks; i++) {
936 ret = dmz_rdwr_block(zmd, REQ_OP_READ,
937 zmd->sb[src_set].block + i, page);
938 if (ret)
939 goto out;
940 ret = dmz_rdwr_block(zmd, REQ_OP_WRITE,
941 zmd->sb[dst_set].block + i, page);
942 if (ret)
943 goto out;
944 }
945
946 /* Finalize with the super block */
947 if (!zmd->sb[dst_set].mblk) {
948 zmd->sb[dst_set].mblk = dmz_alloc_mblock(zmd, 0);
949 if (!zmd->sb[dst_set].mblk) {
950 ret = -ENOMEM;
951 goto out;
952 }
953 zmd->sb[dst_set].sb = zmd->sb[dst_set].mblk->data;
954 }
955
956 ret = dmz_write_sb(zmd, dst_set);
957out:
958 __free_pages(page, 0);
959
960 return ret;
961}
962
963/*
964 * Get super block from disk.
965 */
966static int dmz_load_sb(struct dmz_metadata *zmd)
967{
968 bool sb_good[2] = {false, false};
969 u64 sb_gen[2] = {0, 0};
970 int ret;
971
972 /* Read and check the primary super block */
973 zmd->sb[0].block = dmz_start_block(zmd, zmd->sb_zone);
974 ret = dmz_get_sb(zmd, 0);
975 if (ret) {
976 dmz_dev_err(zmd->dev, "Read primary super block failed");
977 return ret;
978 }
979
980 ret = dmz_check_sb(zmd, zmd->sb[0].sb);
981
982 /* Read and check secondary super block */
983 if (ret == 0) {
984 sb_good[0] = true;
985 zmd->sb[1].block = zmd->sb[0].block +
986 (zmd->nr_meta_zones << zmd->dev->zone_nr_blocks_shift);
987 ret = dmz_get_sb(zmd, 1);
988 } else
989 ret = dmz_lookup_secondary_sb(zmd);
990
991 if (ret) {
992 dmz_dev_err(zmd->dev, "Read secondary super block failed");
993 return ret;
994 }
995
996 ret = dmz_check_sb(zmd, zmd->sb[1].sb);
997 if (ret == 0)
998 sb_good[1] = true;
999
1000 /* Use highest generation sb first */
1001 if (!sb_good[0] && !sb_good[1]) {
1002 dmz_dev_err(zmd->dev, "No valid super block found");
1003 return -EIO;
1004 }
1005
1006 if (sb_good[0])
1007 sb_gen[0] = le64_to_cpu(zmd->sb[0].sb->gen);
1008 else
1009 ret = dmz_recover_mblocks(zmd, 0);
1010
1011 if (sb_good[1])
1012 sb_gen[1] = le64_to_cpu(zmd->sb[1].sb->gen);
1013 else
1014 ret = dmz_recover_mblocks(zmd, 1);
1015
1016 if (ret) {
1017 dmz_dev_err(zmd->dev, "Recovery failed");
1018 return -EIO;
1019 }
1020
1021 if (sb_gen[0] >= sb_gen[1]) {
1022 zmd->sb_gen = sb_gen[0];
1023 zmd->mblk_primary = 0;
1024 } else {
1025 zmd->sb_gen = sb_gen[1];
1026 zmd->mblk_primary = 1;
1027 }
1028
1029 dmz_dev_debug(zmd->dev, "Using super block %u (gen %llu)",
1030 zmd->mblk_primary, zmd->sb_gen);
1031
1032 return 0;
1033}
1034
1035/*
1036 * Initialize a zone descriptor.
1037 */
1038static int dmz_init_zone(struct dmz_metadata *zmd, struct dm_zone *zone,
1039 struct blk_zone *blkz)
1040{
1041 struct dmz_dev *dev = zmd->dev;
1042
1043 /* Ignore the eventual last runt (smaller) zone */
1044 if (blkz->len != dev->zone_nr_sectors) {
1045 if (blkz->start + blkz->len == dev->capacity)
1046 return 0;
1047 return -ENXIO;
1048 }
1049
1050 INIT_LIST_HEAD(&zone->link);
1051 atomic_set(&zone->refcount, 0);
1052 zone->chunk = DMZ_MAP_UNMAPPED;
1053
1054 if (blkz->type == BLK_ZONE_TYPE_CONVENTIONAL) {
1055 set_bit(DMZ_RND, &zone->flags);
1056 zmd->nr_rnd_zones++;
1057 } else if (blkz->type == BLK_ZONE_TYPE_SEQWRITE_REQ ||
1058 blkz->type == BLK_ZONE_TYPE_SEQWRITE_PREF) {
1059 set_bit(DMZ_SEQ, &zone->flags);
1060 } else
1061 return -ENXIO;
1062
1063 if (blkz->cond == BLK_ZONE_COND_OFFLINE)
1064 set_bit(DMZ_OFFLINE, &zone->flags);
1065 else if (blkz->cond == BLK_ZONE_COND_READONLY)
1066 set_bit(DMZ_READ_ONLY, &zone->flags);
1067
1068 if (dmz_is_rnd(zone))
1069 zone->wp_block = 0;
1070 else
1071 zone->wp_block = dmz_sect2blk(blkz->wp - blkz->start);
1072
1073 if (!dmz_is_offline(zone) && !dmz_is_readonly(zone)) {
1074 zmd->nr_useable_zones++;
1075 if (dmz_is_rnd(zone)) {
1076 zmd->nr_rnd_zones++;
1077 if (!zmd->sb_zone) {
1078 /* Super block zone */
1079 zmd->sb_zone = zone;
1080 }
1081 }
1082 }
1083
1084 return 0;
1085}
1086
1087/*
1088 * Free zones descriptors.
1089 */
1090static void dmz_drop_zones(struct dmz_metadata *zmd)
1091{
1092 kfree(zmd->zones);
1093 zmd->zones = NULL;
1094}
1095
1096/*
1097 * The size of a zone report in number of zones.
1098 * This results in 4096*64B=256KB report zones commands.
1099 */
1100#define DMZ_REPORT_NR_ZONES 4096
1101
1102/*
1103 * Allocate and initialize zone descriptors using the zone
1104 * information from disk.
1105 */
1106static int dmz_init_zones(struct dmz_metadata *zmd)
1107{
1108 struct dmz_dev *dev = zmd->dev;
1109 struct dm_zone *zone;
1110 struct blk_zone *blkz;
1111 unsigned int nr_blkz;
1112 sector_t sector = 0;
1113 int i, ret = 0;
1114
1115 /* Init */
1116 zmd->zone_bitmap_size = dev->zone_nr_blocks >> 3;
1117 zmd->zone_nr_bitmap_blocks = zmd->zone_bitmap_size >> DMZ_BLOCK_SHIFT;
1118
1119 /* Allocate zone array */
1120 zmd->zones = kcalloc(dev->nr_zones, sizeof(struct dm_zone), GFP_KERNEL);
1121 if (!zmd->zones)
1122 return -ENOMEM;
1123
1124 dmz_dev_info(dev, "Using %zu B for zone information",
1125 sizeof(struct dm_zone) * dev->nr_zones);
1126
1127 /* Get zone information */
1128 nr_blkz = DMZ_REPORT_NR_ZONES;
1129 blkz = kcalloc(nr_blkz, sizeof(struct blk_zone), GFP_KERNEL);
1130 if (!blkz) {
1131 ret = -ENOMEM;
1132 goto out;
1133 }
1134
1135 /*
1136 * Get zone information and initialize zone descriptors.
1137 * At the same time, determine where the super block
1138 * should be: first block of the first randomly writable
1139 * zone.
1140 */
1141 zone = zmd->zones;
1142 while (sector < dev->capacity) {
1143 /* Get zone information */
1144 nr_blkz = DMZ_REPORT_NR_ZONES;
1145 ret = blkdev_report_zones(dev->bdev, sector, blkz,
1146 &nr_blkz, GFP_KERNEL);
1147 if (ret) {
1148 dmz_dev_err(dev, "Report zones failed %d", ret);
1149 goto out;
1150 }
1151
1152 /* Process report */
1153 for (i = 0; i < nr_blkz; i++) {
1154 ret = dmz_init_zone(zmd, zone, &blkz[i]);
1155 if (ret)
1156 goto out;
1157 sector += dev->zone_nr_sectors;
1158 zone++;
1159 }
1160 }
1161
1162 /* The entire zone configuration of the disk should now be known */
1163 if (sector < dev->capacity) {
1164 dmz_dev_err(dev, "Failed to get correct zone information");
1165 ret = -ENXIO;
1166 }
1167out:
1168 kfree(blkz);
1169 if (ret)
1170 dmz_drop_zones(zmd);
1171
1172 return ret;
1173}
1174
1175/*
1176 * Update a zone information.
1177 */
1178static int dmz_update_zone(struct dmz_metadata *zmd, struct dm_zone *zone)
1179{
1180 unsigned int nr_blkz = 1;
1181 struct blk_zone blkz;
1182 int ret;
1183
1184 /* Get zone information from disk */
1185 ret = blkdev_report_zones(zmd->dev->bdev, dmz_start_sect(zmd, zone),
1186 &blkz, &nr_blkz, GFP_NOIO);
1187 if (ret) {
1188 dmz_dev_err(zmd->dev, "Get zone %u report failed",
1189 dmz_id(zmd, zone));
1190 return ret;
1191 }
1192
1193 clear_bit(DMZ_OFFLINE, &zone->flags);
1194 clear_bit(DMZ_READ_ONLY, &zone->flags);
1195 if (blkz.cond == BLK_ZONE_COND_OFFLINE)
1196 set_bit(DMZ_OFFLINE, &zone->flags);
1197 else if (blkz.cond == BLK_ZONE_COND_READONLY)
1198 set_bit(DMZ_READ_ONLY, &zone->flags);
1199
1200 if (dmz_is_seq(zone))
1201 zone->wp_block = dmz_sect2blk(blkz.wp - blkz.start);
1202 else
1203 zone->wp_block = 0;
1204
1205 return 0;
1206}
1207
1208/*
1209 * Check a zone write pointer position when the zone is marked
1210 * with the sequential write error flag.
1211 */
1212static int dmz_handle_seq_write_err(struct dmz_metadata *zmd,
1213 struct dm_zone *zone)
1214{
1215 unsigned int wp = 0;
1216 int ret;
1217
1218 wp = zone->wp_block;
1219 ret = dmz_update_zone(zmd, zone);
1220 if (ret)
1221 return ret;
1222
1223 dmz_dev_warn(zmd->dev, "Processing zone %u write error (zone wp %u/%u)",
1224 dmz_id(zmd, zone), zone->wp_block, wp);
1225
1226 if (zone->wp_block < wp) {
1227 dmz_invalidate_blocks(zmd, zone, zone->wp_block,
1228 wp - zone->wp_block);
1229 }
1230
1231 return 0;
1232}
1233
1234static struct dm_zone *dmz_get(struct dmz_metadata *zmd, unsigned int zone_id)
1235{
1236 return &zmd->zones[zone_id];
1237}
1238
1239/*
1240 * Reset a zone write pointer.
1241 */
1242static int dmz_reset_zone(struct dmz_metadata *zmd, struct dm_zone *zone)
1243{
1244 int ret;
1245
1246 /*
1247 * Ignore offline zones, read only zones,
1248 * and conventional zones.
1249 */
1250 if (dmz_is_offline(zone) ||
1251 dmz_is_readonly(zone) ||
1252 dmz_is_rnd(zone))
1253 return 0;
1254
1255 if (!dmz_is_empty(zone) || dmz_seq_write_err(zone)) {
1256 struct dmz_dev *dev = zmd->dev;
1257
1258 ret = blkdev_reset_zones(dev->bdev,
1259 dmz_start_sect(zmd, zone),
1260 dev->zone_nr_sectors, GFP_NOIO);
1261 if (ret) {
1262 dmz_dev_err(dev, "Reset zone %u failed %d",
1263 dmz_id(zmd, zone), ret);
1264 return ret;
1265 }
1266 }
1267
1268 /* Clear write error bit and rewind write pointer position */
1269 clear_bit(DMZ_SEQ_WRITE_ERR, &zone->flags);
1270 zone->wp_block = 0;
1271
1272 return 0;
1273}
1274
1275static void dmz_get_zone_weight(struct dmz_metadata *zmd, struct dm_zone *zone);
1276
1277/*
1278 * Initialize chunk mapping.
1279 */
1280static int dmz_load_mapping(struct dmz_metadata *zmd)
1281{
1282 struct dmz_dev *dev = zmd->dev;
1283 struct dm_zone *dzone, *bzone;
1284 struct dmz_mblock *dmap_mblk = NULL;
1285 struct dmz_map *dmap;
1286 unsigned int i = 0, e = 0, chunk = 0;
1287 unsigned int dzone_id;
1288 unsigned int bzone_id;
1289
1290 /* Metadata block array for the chunk mapping table */
1291 zmd->map_mblk = kcalloc(zmd->nr_map_blocks,
1292 sizeof(struct dmz_mblk *), GFP_KERNEL);
1293 if (!zmd->map_mblk)
1294 return -ENOMEM;
1295
1296 /* Get chunk mapping table blocks and initialize zone mapping */
1297 while (chunk < zmd->nr_chunks) {
1298 if (!dmap_mblk) {
1299 /* Get mapping block */
1300 dmap_mblk = dmz_get_mblock(zmd, i + 1);
1301 if (IS_ERR(dmap_mblk))
1302 return PTR_ERR(dmap_mblk);
1303 zmd->map_mblk[i] = dmap_mblk;
1304 dmap = (struct dmz_map *) dmap_mblk->data;
1305 i++;
1306 e = 0;
1307 }
1308
1309 /* Check data zone */
1310 dzone_id = le32_to_cpu(dmap[e].dzone_id);
1311 if (dzone_id == DMZ_MAP_UNMAPPED)
1312 goto next;
1313
1314 if (dzone_id >= dev->nr_zones) {
1315 dmz_dev_err(dev, "Chunk %u mapping: invalid data zone ID %u",
1316 chunk, dzone_id);
1317 return -EIO;
1318 }
1319
1320 dzone = dmz_get(zmd, dzone_id);
1321 set_bit(DMZ_DATA, &dzone->flags);
1322 dzone->chunk = chunk;
1323 dmz_get_zone_weight(zmd, dzone);
1324
1325 if (dmz_is_rnd(dzone))
1326 list_add_tail(&dzone->link, &zmd->map_rnd_list);
1327 else
1328 list_add_tail(&dzone->link, &zmd->map_seq_list);
1329
1330 /* Check buffer zone */
1331 bzone_id = le32_to_cpu(dmap[e].bzone_id);
1332 if (bzone_id == DMZ_MAP_UNMAPPED)
1333 goto next;
1334
1335 if (bzone_id >= dev->nr_zones) {
1336 dmz_dev_err(dev, "Chunk %u mapping: invalid buffer zone ID %u",
1337 chunk, bzone_id);
1338 return -EIO;
1339 }
1340
1341 bzone = dmz_get(zmd, bzone_id);
1342 if (!dmz_is_rnd(bzone)) {
1343 dmz_dev_err(dev, "Chunk %u mapping: invalid buffer zone %u",
1344 chunk, bzone_id);
1345 return -EIO;
1346 }
1347
1348 set_bit(DMZ_DATA, &bzone->flags);
1349 set_bit(DMZ_BUF, &bzone->flags);
1350 bzone->chunk = chunk;
1351 bzone->bzone = dzone;
1352 dzone->bzone = bzone;
1353 dmz_get_zone_weight(zmd, bzone);
1354 list_add_tail(&bzone->link, &zmd->map_rnd_list);
1355next:
1356 chunk++;
1357 e++;
1358 if (e >= DMZ_MAP_ENTRIES)
1359 dmap_mblk = NULL;
1360 }
1361
1362 /*
1363 * At this point, only meta zones and mapped data zones were
1364 * fully initialized. All remaining zones are unmapped data
1365 * zones. Finish initializing those here.
1366 */
1367 for (i = 0; i < dev->nr_zones; i++) {
1368 dzone = dmz_get(zmd, i);
1369 if (dmz_is_meta(dzone))
1370 continue;
1371
1372 if (dmz_is_rnd(dzone))
1373 zmd->nr_rnd++;
1374 else
1375 zmd->nr_seq++;
1376
1377 if (dmz_is_data(dzone)) {
1378 /* Already initialized */
1379 continue;
1380 }
1381
1382 /* Unmapped data zone */
1383 set_bit(DMZ_DATA, &dzone->flags);
1384 dzone->chunk = DMZ_MAP_UNMAPPED;
1385 if (dmz_is_rnd(dzone)) {
1386 list_add_tail(&dzone->link, &zmd->unmap_rnd_list);
1387 atomic_inc(&zmd->unmap_nr_rnd);
1388 } else if (atomic_read(&zmd->nr_reserved_seq_zones) < zmd->nr_reserved_seq) {
1389 list_add_tail(&dzone->link, &zmd->reserved_seq_zones_list);
1390 atomic_inc(&zmd->nr_reserved_seq_zones);
1391 zmd->nr_seq--;
1392 } else {
1393 list_add_tail(&dzone->link, &zmd->unmap_seq_list);
1394 atomic_inc(&zmd->unmap_nr_seq);
1395 }
1396 }
1397
1398 return 0;
1399}
1400
1401/*
1402 * Set a data chunk mapping.
1403 */
1404static void dmz_set_chunk_mapping(struct dmz_metadata *zmd, unsigned int chunk,
1405 unsigned int dzone_id, unsigned int bzone_id)
1406{
1407 struct dmz_mblock *dmap_mblk = zmd->map_mblk[chunk >> DMZ_MAP_ENTRIES_SHIFT];
1408 struct dmz_map *dmap = (struct dmz_map *) dmap_mblk->data;
1409 int map_idx = chunk & DMZ_MAP_ENTRIES_MASK;
1410
1411 dmap[map_idx].dzone_id = cpu_to_le32(dzone_id);
1412 dmap[map_idx].bzone_id = cpu_to_le32(bzone_id);
1413 dmz_dirty_mblock(zmd, dmap_mblk);
1414}
1415
1416/*
1417 * The list of mapped zones is maintained in LRU order.
1418 * This rotates a zone at the end of its map list.
1419 */
1420static void __dmz_lru_zone(struct dmz_metadata *zmd, struct dm_zone *zone)
1421{
1422 if (list_empty(&zone->link))
1423 return;
1424
1425 list_del_init(&zone->link);
1426 if (dmz_is_seq(zone)) {
1427 /* LRU rotate sequential zone */
1428 list_add_tail(&zone->link, &zmd->map_seq_list);
1429 } else {
1430 /* LRU rotate random zone */
1431 list_add_tail(&zone->link, &zmd->map_rnd_list);
1432 }
1433}
1434
1435/*
1436 * The list of mapped random zones is maintained
1437 * in LRU order. This rotates a zone at the end of the list.
1438 */
1439static void dmz_lru_zone(struct dmz_metadata *zmd, struct dm_zone *zone)
1440{
1441 __dmz_lru_zone(zmd, zone);
1442 if (zone->bzone)
1443 __dmz_lru_zone(zmd, zone->bzone);
1444}
1445
1446/*
1447 * Wait for any zone to be freed.
1448 */
1449static void dmz_wait_for_free_zones(struct dmz_metadata *zmd)
1450{
1451 DEFINE_WAIT(wait);
1452
1453 prepare_to_wait(&zmd->free_wq, &wait, TASK_UNINTERRUPTIBLE);
1454 dmz_unlock_map(zmd);
1455 dmz_unlock_metadata(zmd);
1456
1457 io_schedule_timeout(HZ);
1458
1459 dmz_lock_metadata(zmd);
1460 dmz_lock_map(zmd);
1461 finish_wait(&zmd->free_wq, &wait);
1462}
1463
1464/*
1465 * Lock a zone for reclaim (set the zone RECLAIM bit).
1466 * Returns false if the zone cannot be locked or if it is already locked
1467 * and 1 otherwise.
1468 */
1469int dmz_lock_zone_reclaim(struct dm_zone *zone)
1470{
1471 /* Active zones cannot be reclaimed */
1472 if (dmz_is_active(zone))
1473 return 0;
1474
1475 return !test_and_set_bit(DMZ_RECLAIM, &zone->flags);
1476}
1477
1478/*
1479 * Clear a zone reclaim flag.
1480 */
1481void dmz_unlock_zone_reclaim(struct dm_zone *zone)
1482{
1483 WARN_ON(dmz_is_active(zone));
1484 WARN_ON(!dmz_in_reclaim(zone));
1485
1486 clear_bit_unlock(DMZ_RECLAIM, &zone->flags);
1487 smp_mb__after_atomic();
1488 wake_up_bit(&zone->flags, DMZ_RECLAIM);
1489}
1490
1491/*
1492 * Wait for a zone reclaim to complete.
1493 */
1494static void dmz_wait_for_reclaim(struct dmz_metadata *zmd, struct dm_zone *zone)
1495{
1496 dmz_unlock_map(zmd);
1497 dmz_unlock_metadata(zmd);
1498 wait_on_bit_timeout(&zone->flags, DMZ_RECLAIM, TASK_UNINTERRUPTIBLE, HZ);
1499 dmz_lock_metadata(zmd);
1500 dmz_lock_map(zmd);
1501}
1502
1503/*
1504 * Select a random write zone for reclaim.
1505 */
1506static struct dm_zone *dmz_get_rnd_zone_for_reclaim(struct dmz_metadata *zmd)
1507{
1508 struct dm_zone *dzone = NULL;
1509 struct dm_zone *zone;
1510
1511 if (list_empty(&zmd->map_rnd_list))
1512 return NULL;
1513
1514 list_for_each_entry(zone, &zmd->map_rnd_list, link) {
1515 if (dmz_is_buf(zone))
1516 dzone = zone->bzone;
1517 else
1518 dzone = zone;
1519 if (dmz_lock_zone_reclaim(dzone))
1520 return dzone;
1521 }
1522
1523 return NULL;
1524}
1525
1526/*
1527 * Select a buffered sequential zone for reclaim.
1528 */
1529static struct dm_zone *dmz_get_seq_zone_for_reclaim(struct dmz_metadata *zmd)
1530{
1531 struct dm_zone *zone;
1532
1533 if (list_empty(&zmd->map_seq_list))
1534 return NULL;
1535
1536 list_for_each_entry(zone, &zmd->map_seq_list, link) {
1537 if (!zone->bzone)
1538 continue;
1539 if (dmz_lock_zone_reclaim(zone))
1540 return zone;
1541 }
1542
1543 return NULL;
1544}
1545
1546/*
1547 * Select a zone for reclaim.
1548 */
1549struct dm_zone *dmz_get_zone_for_reclaim(struct dmz_metadata *zmd)
1550{
1551 struct dm_zone *zone;
1552
1553 /*
1554 * Search for a zone candidate to reclaim: 2 cases are possible.
1555 * (1) There is no free sequential zones. Then a random data zone
1556 * cannot be reclaimed. So choose a sequential zone to reclaim so
1557 * that afterward a random zone can be reclaimed.
1558 * (2) At least one free sequential zone is available, then choose
1559 * the oldest random zone (data or buffer) that can be locked.
1560 */
1561 dmz_lock_map(zmd);
1562 if (list_empty(&zmd->reserved_seq_zones_list))
1563 zone = dmz_get_seq_zone_for_reclaim(zmd);
1564 else
1565 zone = dmz_get_rnd_zone_for_reclaim(zmd);
1566 dmz_unlock_map(zmd);
1567
1568 return zone;
1569}
1570
1571/*
1572 * Activate a zone (increment its reference count).
1573 */
1574void dmz_activate_zone(struct dm_zone *zone)
1575{
1576 set_bit(DMZ_ACTIVE, &zone->flags);
1577 atomic_inc(&zone->refcount);
1578}
1579
1580/*
1581 * Deactivate a zone. This decrement the zone reference counter
1582 * and clears the active state of the zone once the count reaches 0,
1583 * indicating that all BIOs to the zone have completed. Returns
1584 * true if the zone was deactivated.
1585 */
1586void dmz_deactivate_zone(struct dm_zone *zone)
1587{
1588 if (atomic_dec_and_test(&zone->refcount)) {
1589 WARN_ON(!test_bit(DMZ_ACTIVE, &zone->flags));
1590 clear_bit_unlock(DMZ_ACTIVE, &zone->flags);
1591 smp_mb__after_atomic();
1592 }
1593}
1594
1595/*
1596 * Get the zone mapping a chunk, if the chunk is mapped already.
1597 * If no mapping exist and the operation is WRITE, a zone is
1598 * allocated and used to map the chunk.
1599 * The zone returned will be set to the active state.
1600 */
1601struct dm_zone *dmz_get_chunk_mapping(struct dmz_metadata *zmd, unsigned int chunk, int op)
1602{
1603 struct dmz_mblock *dmap_mblk = zmd->map_mblk[chunk >> DMZ_MAP_ENTRIES_SHIFT];
1604 struct dmz_map *dmap = (struct dmz_map *) dmap_mblk->data;
1605 int dmap_idx = chunk & DMZ_MAP_ENTRIES_MASK;
1606 unsigned int dzone_id;
1607 struct dm_zone *dzone = NULL;
1608 int ret = 0;
1609
1610 dmz_lock_map(zmd);
1611again:
1612 /* Get the chunk mapping */
1613 dzone_id = le32_to_cpu(dmap[dmap_idx].dzone_id);
1614 if (dzone_id == DMZ_MAP_UNMAPPED) {
1615 /*
1616 * Read or discard in unmapped chunks are fine. But for
1617 * writes, we need a mapping, so get one.
1618 */
1619 if (op != REQ_OP_WRITE)
1620 goto out;
1621
1622 /* Alloate a random zone */
1623 dzone = dmz_alloc_zone(zmd, DMZ_ALLOC_RND);
1624 if (!dzone) {
1625 dmz_wait_for_free_zones(zmd);
1626 goto again;
1627 }
1628
1629 dmz_map_zone(zmd, dzone, chunk);
1630
1631 } else {
1632 /* The chunk is already mapped: get the mapping zone */
1633 dzone = dmz_get(zmd, dzone_id);
1634 if (dzone->chunk != chunk) {
1635 dzone = ERR_PTR(-EIO);
1636 goto out;
1637 }
1638
1639 /* Repair write pointer if the sequential dzone has error */
1640 if (dmz_seq_write_err(dzone)) {
1641 ret = dmz_handle_seq_write_err(zmd, dzone);
1642 if (ret) {
1643 dzone = ERR_PTR(-EIO);
1644 goto out;
1645 }
1646 clear_bit(DMZ_SEQ_WRITE_ERR, &dzone->flags);
1647 }
1648 }
1649
1650 /*
1651 * If the zone is being reclaimed, the chunk mapping may change
1652 * to a different zone. So wait for reclaim and retry. Otherwise,
1653 * activate the zone (this will prevent reclaim from touching it).
1654 */
1655 if (dmz_in_reclaim(dzone)) {
1656 dmz_wait_for_reclaim(zmd, dzone);
1657 goto again;
1658 }
1659 dmz_activate_zone(dzone);
1660 dmz_lru_zone(zmd, dzone);
1661out:
1662 dmz_unlock_map(zmd);
1663
1664 return dzone;
1665}
1666
1667/*
1668 * Write and discard change the block validity of data zones and their buffer
1669 * zones. Check here that valid blocks are still present. If all blocks are
1670 * invalid, the zones can be unmapped on the fly without waiting for reclaim
1671 * to do it.
1672 */
1673void dmz_put_chunk_mapping(struct dmz_metadata *zmd, struct dm_zone *dzone)
1674{
1675 struct dm_zone *bzone;
1676
1677 dmz_lock_map(zmd);
1678
1679 bzone = dzone->bzone;
1680 if (bzone) {
1681 if (dmz_weight(bzone))
1682 dmz_lru_zone(zmd, bzone);
1683 else {
1684 /* Empty buffer zone: reclaim it */
1685 dmz_unmap_zone(zmd, bzone);
1686 dmz_free_zone(zmd, bzone);
1687 bzone = NULL;
1688 }
1689 }
1690
1691 /* Deactivate the data zone */
1692 dmz_deactivate_zone(dzone);
1693 if (dmz_is_active(dzone) || bzone || dmz_weight(dzone))
1694 dmz_lru_zone(zmd, dzone);
1695 else {
1696 /* Unbuffered inactive empty data zone: reclaim it */
1697 dmz_unmap_zone(zmd, dzone);
1698 dmz_free_zone(zmd, dzone);
1699 }
1700
1701 dmz_unlock_map(zmd);
1702}
1703
1704/*
1705 * Allocate and map a random zone to buffer a chunk
1706 * already mapped to a sequential zone.
1707 */
1708struct dm_zone *dmz_get_chunk_buffer(struct dmz_metadata *zmd,
1709 struct dm_zone *dzone)
1710{
1711 struct dm_zone *bzone;
1712
1713 dmz_lock_map(zmd);
1714again:
1715 bzone = dzone->bzone;
1716 if (bzone)
1717 goto out;
1718
1719 /* Alloate a random zone */
1720 bzone = dmz_alloc_zone(zmd, DMZ_ALLOC_RND);
1721 if (!bzone) {
1722 dmz_wait_for_free_zones(zmd);
1723 goto again;
1724 }
1725
1726 /* Update the chunk mapping */
1727 dmz_set_chunk_mapping(zmd, dzone->chunk, dmz_id(zmd, dzone),
1728 dmz_id(zmd, bzone));
1729
1730 set_bit(DMZ_BUF, &bzone->flags);
1731 bzone->chunk = dzone->chunk;
1732 bzone->bzone = dzone;
1733 dzone->bzone = bzone;
1734 list_add_tail(&bzone->link, &zmd->map_rnd_list);
1735out:
1736 dmz_unlock_map(zmd);
1737
1738 return bzone;
1739}
1740
1741/*
1742 * Get an unmapped (free) zone.
1743 * This must be called with the mapping lock held.
1744 */
1745struct dm_zone *dmz_alloc_zone(struct dmz_metadata *zmd, unsigned long flags)
1746{
1747 struct list_head *list;
1748 struct dm_zone *zone;
1749
1750 if (flags & DMZ_ALLOC_RND)
1751 list = &zmd->unmap_rnd_list;
1752 else
1753 list = &zmd->unmap_seq_list;
1754again:
1755 if (list_empty(list)) {
1756 /*
1757 * No free zone: if this is for reclaim, allow using the
1758 * reserved sequential zones.
1759 */
1760 if (!(flags & DMZ_ALLOC_RECLAIM) ||
1761 list_empty(&zmd->reserved_seq_zones_list))
1762 return NULL;
1763
1764 zone = list_first_entry(&zmd->reserved_seq_zones_list,
1765 struct dm_zone, link);
1766 list_del_init(&zone->link);
1767 atomic_dec(&zmd->nr_reserved_seq_zones);
1768 return zone;
1769 }
1770
1771 zone = list_first_entry(list, struct dm_zone, link);
1772 list_del_init(&zone->link);
1773
1774 if (dmz_is_rnd(zone))
1775 atomic_dec(&zmd->unmap_nr_rnd);
1776 else
1777 atomic_dec(&zmd->unmap_nr_seq);
1778
1779 if (dmz_is_offline(zone)) {
1780 dmz_dev_warn(zmd->dev, "Zone %u is offline", dmz_id(zmd, zone));
1781 zone = NULL;
1782 goto again;
1783 }
1784
1785 return zone;
1786}
1787
1788/*
1789 * Free a zone.
1790 * This must be called with the mapping lock held.
1791 */
1792void dmz_free_zone(struct dmz_metadata *zmd, struct dm_zone *zone)
1793{
1794 /* If this is a sequential zone, reset it */
1795 if (dmz_is_seq(zone))
1796 dmz_reset_zone(zmd, zone);
1797
1798 /* Return the zone to its type unmap list */
1799 if (dmz_is_rnd(zone)) {
1800 list_add_tail(&zone->link, &zmd->unmap_rnd_list);
1801 atomic_inc(&zmd->unmap_nr_rnd);
1802 } else if (atomic_read(&zmd->nr_reserved_seq_zones) <
1803 zmd->nr_reserved_seq) {
1804 list_add_tail(&zone->link, &zmd->reserved_seq_zones_list);
1805 atomic_inc(&zmd->nr_reserved_seq_zones);
1806 } else {
1807 list_add_tail(&zone->link, &zmd->unmap_seq_list);
1808 atomic_inc(&zmd->unmap_nr_seq);
1809 }
1810
1811 wake_up_all(&zmd->free_wq);
1812}
1813
1814/*
1815 * Map a chunk to a zone.
1816 * This must be called with the mapping lock held.
1817 */
1818void dmz_map_zone(struct dmz_metadata *zmd, struct dm_zone *dzone,
1819 unsigned int chunk)
1820{
1821 /* Set the chunk mapping */
1822 dmz_set_chunk_mapping(zmd, chunk, dmz_id(zmd, dzone),
1823 DMZ_MAP_UNMAPPED);
1824 dzone->chunk = chunk;
1825 if (dmz_is_rnd(dzone))
1826 list_add_tail(&dzone->link, &zmd->map_rnd_list);
1827 else
1828 list_add_tail(&dzone->link, &zmd->map_seq_list);
1829}
1830
1831/*
1832 * Unmap a zone.
1833 * This must be called with the mapping lock held.
1834 */
1835void dmz_unmap_zone(struct dmz_metadata *zmd, struct dm_zone *zone)
1836{
1837 unsigned int chunk = zone->chunk;
1838 unsigned int dzone_id;
1839
1840 if (chunk == DMZ_MAP_UNMAPPED) {
1841 /* Already unmapped */
1842 return;
1843 }
1844
1845 if (test_and_clear_bit(DMZ_BUF, &zone->flags)) {
1846 /*
1847 * Unmapping the chunk buffer zone: clear only
1848 * the chunk buffer mapping
1849 */
1850 dzone_id = dmz_id(zmd, zone->bzone);
1851 zone->bzone->bzone = NULL;
1852 zone->bzone = NULL;
1853
1854 } else {
1855 /*
1856 * Unmapping the chunk data zone: the zone must
1857 * not be buffered.
1858 */
1859 if (WARN_ON(zone->bzone)) {
1860 zone->bzone->bzone = NULL;
1861 zone->bzone = NULL;
1862 }
1863 dzone_id = DMZ_MAP_UNMAPPED;
1864 }
1865
1866 dmz_set_chunk_mapping(zmd, chunk, dzone_id, DMZ_MAP_UNMAPPED);
1867
1868 zone->chunk = DMZ_MAP_UNMAPPED;
1869 list_del_init(&zone->link);
1870}
1871
1872/*
1873 * Set @nr_bits bits in @bitmap starting from @bit.
1874 * Return the number of bits changed from 0 to 1.
1875 */
1876static unsigned int dmz_set_bits(unsigned long *bitmap,
1877 unsigned int bit, unsigned int nr_bits)
1878{
1879 unsigned long *addr;
1880 unsigned int end = bit + nr_bits;
1881 unsigned int n = 0;
1882
1883 while (bit < end) {
1884 if (((bit & (BITS_PER_LONG - 1)) == 0) &&
1885 ((end - bit) >= BITS_PER_LONG)) {
1886 /* Try to set the whole word at once */
1887 addr = bitmap + BIT_WORD(bit);
1888 if (*addr == 0) {
1889 *addr = ULONG_MAX;
1890 n += BITS_PER_LONG;
1891 bit += BITS_PER_LONG;
1892 continue;
1893 }
1894 }
1895
1896 if (!test_and_set_bit(bit, bitmap))
1897 n++;
1898 bit++;
1899 }
1900
1901 return n;
1902}
1903
1904/*
1905 * Get the bitmap block storing the bit for chunk_block in zone.
1906 */
1907static struct dmz_mblock *dmz_get_bitmap(struct dmz_metadata *zmd,
1908 struct dm_zone *zone,
1909 sector_t chunk_block)
1910{
1911 sector_t bitmap_block = 1 + zmd->nr_map_blocks +
1912 (sector_t)(dmz_id(zmd, zone) * zmd->zone_nr_bitmap_blocks) +
1913 (chunk_block >> DMZ_BLOCK_SHIFT_BITS);
1914
1915 return dmz_get_mblock(zmd, bitmap_block);
1916}
1917
1918/*
1919 * Copy the valid blocks bitmap of from_zone to the bitmap of to_zone.
1920 */
1921int dmz_copy_valid_blocks(struct dmz_metadata *zmd, struct dm_zone *from_zone,
1922 struct dm_zone *to_zone)
1923{
1924 struct dmz_mblock *from_mblk, *to_mblk;
1925 sector_t chunk_block = 0;
1926
1927 /* Get the zones bitmap blocks */
1928 while (chunk_block < zmd->dev->zone_nr_blocks) {
1929 from_mblk = dmz_get_bitmap(zmd, from_zone, chunk_block);
1930 if (IS_ERR(from_mblk))
1931 return PTR_ERR(from_mblk);
1932 to_mblk = dmz_get_bitmap(zmd, to_zone, chunk_block);
1933 if (IS_ERR(to_mblk)) {
1934 dmz_release_mblock(zmd, from_mblk);
1935 return PTR_ERR(to_mblk);
1936 }
1937
1938 memcpy(to_mblk->data, from_mblk->data, DMZ_BLOCK_SIZE);
1939 dmz_dirty_mblock(zmd, to_mblk);
1940
1941 dmz_release_mblock(zmd, to_mblk);
1942 dmz_release_mblock(zmd, from_mblk);
1943
1944 chunk_block += DMZ_BLOCK_SIZE_BITS;
1945 }
1946
1947 to_zone->weight = from_zone->weight;
1948
1949 return 0;
1950}
1951
1952/*
1953 * Merge the valid blocks bitmap of from_zone into the bitmap of to_zone,
1954 * starting from chunk_block.
1955 */
1956int dmz_merge_valid_blocks(struct dmz_metadata *zmd, struct dm_zone *from_zone,
1957 struct dm_zone *to_zone, sector_t chunk_block)
1958{
1959 unsigned int nr_blocks;
1960 int ret;
1961
1962 /* Get the zones bitmap blocks */
1963 while (chunk_block < zmd->dev->zone_nr_blocks) {
1964 /* Get a valid region from the source zone */
1965 ret = dmz_first_valid_block(zmd, from_zone, &chunk_block);
1966 if (ret <= 0)
1967 return ret;
1968
1969 nr_blocks = ret;
1970 ret = dmz_validate_blocks(zmd, to_zone, chunk_block, nr_blocks);
1971 if (ret)
1972 return ret;
1973
1974 chunk_block += nr_blocks;
1975 }
1976
1977 return 0;
1978}
1979
1980/*
1981 * Validate all the blocks in the range [block..block+nr_blocks-1].
1982 */
1983int dmz_validate_blocks(struct dmz_metadata *zmd, struct dm_zone *zone,
1984 sector_t chunk_block, unsigned int nr_blocks)
1985{
1986 unsigned int count, bit, nr_bits;
1987 unsigned int zone_nr_blocks = zmd->dev->zone_nr_blocks;
1988 struct dmz_mblock *mblk;
1989 unsigned int n = 0;
1990
1991 dmz_dev_debug(zmd->dev, "=> VALIDATE zone %u, block %llu, %u blocks",
1992 dmz_id(zmd, zone), (unsigned long long)chunk_block,
1993 nr_blocks);
1994
1995 WARN_ON(chunk_block + nr_blocks > zone_nr_blocks);
1996
1997 while (nr_blocks) {
1998 /* Get bitmap block */
1999 mblk = dmz_get_bitmap(zmd, zone, chunk_block);
2000 if (IS_ERR(mblk))
2001 return PTR_ERR(mblk);
2002
2003 /* Set bits */
2004 bit = chunk_block & DMZ_BLOCK_MASK_BITS;
2005 nr_bits = min(nr_blocks, DMZ_BLOCK_SIZE_BITS - bit);
2006
2007 count = dmz_set_bits((unsigned long *)mblk->data, bit, nr_bits);
2008 if (count) {
2009 dmz_dirty_mblock(zmd, mblk);
2010 n += count;
2011 }
2012 dmz_release_mblock(zmd, mblk);
2013
2014 nr_blocks -= nr_bits;
2015 chunk_block += nr_bits;
2016 }
2017
2018 if (likely(zone->weight + n <= zone_nr_blocks))
2019 zone->weight += n;
2020 else {
2021 dmz_dev_warn(zmd->dev, "Zone %u: weight %u should be <= %u",
2022 dmz_id(zmd, zone), zone->weight,
2023 zone_nr_blocks - n);
2024 zone->weight = zone_nr_blocks;
2025 }
2026
2027 return 0;
2028}
2029
2030/*
2031 * Clear nr_bits bits in bitmap starting from bit.
2032 * Return the number of bits cleared.
2033 */
2034static int dmz_clear_bits(unsigned long *bitmap, int bit, int nr_bits)
2035{
2036 unsigned long *addr;
2037 int end = bit + nr_bits;
2038 int n = 0;
2039
2040 while (bit < end) {
2041 if (((bit & (BITS_PER_LONG - 1)) == 0) &&
2042 ((end - bit) >= BITS_PER_LONG)) {
2043 /* Try to clear whole word at once */
2044 addr = bitmap + BIT_WORD(bit);
2045 if (*addr == ULONG_MAX) {
2046 *addr = 0;
2047 n += BITS_PER_LONG;
2048 bit += BITS_PER_LONG;
2049 continue;
2050 }
2051 }
2052
2053 if (test_and_clear_bit(bit, bitmap))
2054 n++;
2055 bit++;
2056 }
2057
2058 return n;
2059}
2060
2061/*
2062 * Invalidate all the blocks in the range [block..block+nr_blocks-1].
2063 */
2064int dmz_invalidate_blocks(struct dmz_metadata *zmd, struct dm_zone *zone,
2065 sector_t chunk_block, unsigned int nr_blocks)
2066{
2067 unsigned int count, bit, nr_bits;
2068 struct dmz_mblock *mblk;
2069 unsigned int n = 0;
2070
2071 dmz_dev_debug(zmd->dev, "=> INVALIDATE zone %u, block %llu, %u blocks",
2072 dmz_id(zmd, zone), (u64)chunk_block, nr_blocks);
2073
2074 WARN_ON(chunk_block + nr_blocks > zmd->dev->zone_nr_blocks);
2075
2076 while (nr_blocks) {
2077 /* Get bitmap block */
2078 mblk = dmz_get_bitmap(zmd, zone, chunk_block);
2079 if (IS_ERR(mblk))
2080 return PTR_ERR(mblk);
2081
2082 /* Clear bits */
2083 bit = chunk_block & DMZ_BLOCK_MASK_BITS;
2084 nr_bits = min(nr_blocks, DMZ_BLOCK_SIZE_BITS - bit);
2085
2086 count = dmz_clear_bits((unsigned long *)mblk->data,
2087 bit, nr_bits);
2088 if (count) {
2089 dmz_dirty_mblock(zmd, mblk);
2090 n += count;
2091 }
2092 dmz_release_mblock(zmd, mblk);
2093
2094 nr_blocks -= nr_bits;
2095 chunk_block += nr_bits;
2096 }
2097
2098 if (zone->weight >= n)
2099 zone->weight -= n;
2100 else {
2101 dmz_dev_warn(zmd->dev, "Zone %u: weight %u should be >= %u",
2102 dmz_id(zmd, zone), zone->weight, n);
2103 zone->weight = 0;
2104 }
2105
2106 return 0;
2107}
2108
2109/*
2110 * Get a block bit value.
2111 */
2112static int dmz_test_block(struct dmz_metadata *zmd, struct dm_zone *zone,
2113 sector_t chunk_block)
2114{
2115 struct dmz_mblock *mblk;
2116 int ret;
2117
2118 WARN_ON(chunk_block >= zmd->dev->zone_nr_blocks);
2119
2120 /* Get bitmap block */
2121 mblk = dmz_get_bitmap(zmd, zone, chunk_block);
2122 if (IS_ERR(mblk))
2123 return PTR_ERR(mblk);
2124
2125 /* Get offset */
2126 ret = test_bit(chunk_block & DMZ_BLOCK_MASK_BITS,
2127 (unsigned long *) mblk->data) != 0;
2128
2129 dmz_release_mblock(zmd, mblk);
2130
2131 return ret;
2132}
2133
2134/*
2135 * Return the number of blocks from chunk_block to the first block with a bit
2136 * value specified by set. Search at most nr_blocks blocks from chunk_block.
2137 */
2138static int dmz_to_next_set_block(struct dmz_metadata *zmd, struct dm_zone *zone,
2139 sector_t chunk_block, unsigned int nr_blocks,
2140 int set)
2141{
2142 struct dmz_mblock *mblk;
2143 unsigned int bit, set_bit, nr_bits;
2144 unsigned long *bitmap;
2145 int n = 0;
2146
2147 WARN_ON(chunk_block + nr_blocks > zmd->dev->zone_nr_blocks);
2148
2149 while (nr_blocks) {
2150 /* Get bitmap block */
2151 mblk = dmz_get_bitmap(zmd, zone, chunk_block);
2152 if (IS_ERR(mblk))
2153 return PTR_ERR(mblk);
2154
2155 /* Get offset */
2156 bitmap = (unsigned long *) mblk->data;
2157 bit = chunk_block & DMZ_BLOCK_MASK_BITS;
2158 nr_bits = min(nr_blocks, DMZ_BLOCK_SIZE_BITS - bit);
2159 if (set)
2160 set_bit = find_next_bit(bitmap, DMZ_BLOCK_SIZE_BITS, bit);
2161 else
2162 set_bit = find_next_zero_bit(bitmap, DMZ_BLOCK_SIZE_BITS, bit);
2163 dmz_release_mblock(zmd, mblk);
2164
2165 n += set_bit - bit;
2166 if (set_bit < DMZ_BLOCK_SIZE_BITS)
2167 break;
2168
2169 nr_blocks -= nr_bits;
2170 chunk_block += nr_bits;
2171 }
2172
2173 return n;
2174}
2175
2176/*
2177 * Test if chunk_block is valid. If it is, the number of consecutive
2178 * valid blocks from chunk_block will be returned.
2179 */
2180int dmz_block_valid(struct dmz_metadata *zmd, struct dm_zone *zone,
2181 sector_t chunk_block)
2182{
2183 int valid;
2184
2185 valid = dmz_test_block(zmd, zone, chunk_block);
2186 if (valid <= 0)
2187 return valid;
2188
2189 /* The block is valid: get the number of valid blocks from block */
2190 return dmz_to_next_set_block(zmd, zone, chunk_block,
2191 zmd->dev->zone_nr_blocks - chunk_block, 0);
2192}
2193
2194/*
2195 * Find the first valid block from @chunk_block in @zone.
2196 * If such a block is found, its number is returned using
2197 * @chunk_block and the total number of valid blocks from @chunk_block
2198 * is returned.
2199 */
2200int dmz_first_valid_block(struct dmz_metadata *zmd, struct dm_zone *zone,
2201 sector_t *chunk_block)
2202{
2203 sector_t start_block = *chunk_block;
2204 int ret;
2205
2206 ret = dmz_to_next_set_block(zmd, zone, start_block,
2207 zmd->dev->zone_nr_blocks - start_block, 1);
2208 if (ret < 0)
2209 return ret;
2210
2211 start_block += ret;
2212 *chunk_block = start_block;
2213
2214 return dmz_to_next_set_block(zmd, zone, start_block,
2215 zmd->dev->zone_nr_blocks - start_block, 0);
2216}
2217
2218/*
2219 * Count the number of bits set starting from bit up to bit + nr_bits - 1.
2220 */
2221static int dmz_count_bits(void *bitmap, int bit, int nr_bits)
2222{
2223 unsigned long *addr;
2224 int end = bit + nr_bits;
2225 int n = 0;
2226
2227 while (bit < end) {
2228 if (((bit & (BITS_PER_LONG - 1)) == 0) &&
2229 ((end - bit) >= BITS_PER_LONG)) {
2230 addr = (unsigned long *)bitmap + BIT_WORD(bit);
2231 if (*addr == ULONG_MAX) {
2232 n += BITS_PER_LONG;
2233 bit += BITS_PER_LONG;
2234 continue;
2235 }
2236 }
2237
2238 if (test_bit(bit, bitmap))
2239 n++;
2240 bit++;
2241 }
2242
2243 return n;
2244}
2245
2246/*
2247 * Get a zone weight.
2248 */
2249static void dmz_get_zone_weight(struct dmz_metadata *zmd, struct dm_zone *zone)
2250{
2251 struct dmz_mblock *mblk;
2252 sector_t chunk_block = 0;
2253 unsigned int bit, nr_bits;
2254 unsigned int nr_blocks = zmd->dev->zone_nr_blocks;
2255 void *bitmap;
2256 int n = 0;
2257
2258 while (nr_blocks) {
2259 /* Get bitmap block */
2260 mblk = dmz_get_bitmap(zmd, zone, chunk_block);
2261 if (IS_ERR(mblk)) {
2262 n = 0;
2263 break;
2264 }
2265
2266 /* Count bits in this block */
2267 bitmap = mblk->data;
2268 bit = chunk_block & DMZ_BLOCK_MASK_BITS;
2269 nr_bits = min(nr_blocks, DMZ_BLOCK_SIZE_BITS - bit);
2270 n += dmz_count_bits(bitmap, bit, nr_bits);
2271
2272 dmz_release_mblock(zmd, mblk);
2273
2274 nr_blocks -= nr_bits;
2275 chunk_block += nr_bits;
2276 }
2277
2278 zone->weight = n;
2279}
2280
2281/*
2282 * Cleanup the zoned metadata resources.
2283 */
2284static void dmz_cleanup_metadata(struct dmz_metadata *zmd)
2285{
2286 struct rb_root *root;
2287 struct dmz_mblock *mblk, *next;
2288 int i;
2289
2290 /* Release zone mapping resources */
2291 if (zmd->map_mblk) {
2292 for (i = 0; i < zmd->nr_map_blocks; i++)
2293 dmz_release_mblock(zmd, zmd->map_mblk[i]);
2294 kfree(zmd->map_mblk);
2295 zmd->map_mblk = NULL;
2296 }
2297
2298 /* Release super blocks */
2299 for (i = 0; i < 2; i++) {
2300 if (zmd->sb[i].mblk) {
2301 dmz_free_mblock(zmd, zmd->sb[i].mblk);
2302 zmd->sb[i].mblk = NULL;
2303 }
2304 }
2305
2306 /* Free cached blocks */
2307 while (!list_empty(&zmd->mblk_dirty_list)) {
2308 mblk = list_first_entry(&zmd->mblk_dirty_list,
2309 struct dmz_mblock, link);
2310 dmz_dev_warn(zmd->dev, "mblock %llu still in dirty list (ref %u)",
2311 (u64)mblk->no, atomic_read(&mblk->ref));
2312 list_del_init(&mblk->link);
2313 rb_erase(&mblk->node, &zmd->mblk_rbtree);
2314 dmz_free_mblock(zmd, mblk);
2315 }
2316
2317 while (!list_empty(&zmd->mblk_lru_list)) {
2318 mblk = list_first_entry(&zmd->mblk_lru_list,
2319 struct dmz_mblock, link);
2320 list_del_init(&mblk->link);
2321 rb_erase(&mblk->node, &zmd->mblk_rbtree);
2322 dmz_free_mblock(zmd, mblk);
2323 }
2324
2325 /* Sanity checks: the mblock rbtree should now be empty */
2326 root = &zmd->mblk_rbtree;
2327 rbtree_postorder_for_each_entry_safe(mblk, next, root, node) {
2328 dmz_dev_warn(zmd->dev, "mblock %llu ref %u still in rbtree",
2329 (u64)mblk->no, atomic_read(&mblk->ref));
2330 atomic_set(&mblk->ref, 0);
2331 dmz_free_mblock(zmd, mblk);
2332 }
2333
2334 /* Free the zone descriptors */
2335 dmz_drop_zones(zmd);
2336
2337 mutex_destroy(&zmd->mblk_flush_lock);
2338 mutex_destroy(&zmd->map_lock);
2339}
2340
2341/*
2342 * Initialize the zoned metadata.
2343 */
2344int dmz_ctr_metadata(struct dmz_dev *dev, struct dmz_metadata **metadata)
2345{
2346 struct dmz_metadata *zmd;
2347 unsigned int i, zid;
2348 struct dm_zone *zone;
2349 int ret;
2350
2351 zmd = kzalloc(sizeof(struct dmz_metadata), GFP_KERNEL);
2352 if (!zmd)
2353 return -ENOMEM;
2354
2355 zmd->dev = dev;
2356 zmd->mblk_rbtree = RB_ROOT;
2357 init_rwsem(&zmd->mblk_sem);
2358 mutex_init(&zmd->mblk_flush_lock);
2359 spin_lock_init(&zmd->mblk_lock);
2360 INIT_LIST_HEAD(&zmd->mblk_lru_list);
2361 INIT_LIST_HEAD(&zmd->mblk_dirty_list);
2362
2363 mutex_init(&zmd->map_lock);
2364 atomic_set(&zmd->unmap_nr_rnd, 0);
2365 INIT_LIST_HEAD(&zmd->unmap_rnd_list);
2366 INIT_LIST_HEAD(&zmd->map_rnd_list);
2367
2368 atomic_set(&zmd->unmap_nr_seq, 0);
2369 INIT_LIST_HEAD(&zmd->unmap_seq_list);
2370 INIT_LIST_HEAD(&zmd->map_seq_list);
2371
2372 atomic_set(&zmd->nr_reserved_seq_zones, 0);
2373 INIT_LIST_HEAD(&zmd->reserved_seq_zones_list);
2374
2375 init_waitqueue_head(&zmd->free_wq);
2376
2377 /* Initialize zone descriptors */
2378 ret = dmz_init_zones(zmd);
2379 if (ret)
2380 goto err;
2381
2382 /* Get super block */
2383 ret = dmz_load_sb(zmd);
2384 if (ret)
2385 goto err;
2386
2387 /* Set metadata zones starting from sb_zone */
2388 zid = dmz_id(zmd, zmd->sb_zone);
2389 for (i = 0; i < zmd->nr_meta_zones << 1; i++) {
2390 zone = dmz_get(zmd, zid + i);
2391 if (!dmz_is_rnd(zone))
2392 goto err;
2393 set_bit(DMZ_META, &zone->flags);
2394 }
2395
2396 /* Load mapping table */
2397 ret = dmz_load_mapping(zmd);
2398 if (ret)
2399 goto err;
2400
2401 /*
2402 * Cache size boundaries: allow at least 2 super blocks, the chunk map
2403 * blocks and enough blocks to be able to cache the bitmap blocks of
2404 * up to 16 zones when idle (min_nr_mblks). Otherwise, if busy, allow
2405 * the cache to add 512 more metadata blocks.
2406 */
2407 zmd->min_nr_mblks = 2 + zmd->nr_map_blocks + zmd->zone_nr_bitmap_blocks * 16;
2408 zmd->max_nr_mblks = zmd->min_nr_mblks + 512;
2409 zmd->mblk_shrinker.count_objects = dmz_mblock_shrinker_count;
2410 zmd->mblk_shrinker.scan_objects = dmz_mblock_shrinker_scan;
2411 zmd->mblk_shrinker.seeks = DEFAULT_SEEKS;
2412
2413 /* Metadata cache shrinker */
2414 ret = register_shrinker(&zmd->mblk_shrinker);
2415 if (ret) {
2416 dmz_dev_err(dev, "Register metadata cache shrinker failed");
2417 goto err;
2418 }
2419
2420 dmz_dev_info(dev, "Host-%s zoned block device",
2421 bdev_zoned_model(dev->bdev) == BLK_ZONED_HA ?
2422 "aware" : "managed");
2423 dmz_dev_info(dev, " %llu 512-byte logical sectors",
2424 (u64)dev->capacity);
2425 dmz_dev_info(dev, " %u zones of %llu 512-byte logical sectors",
2426 dev->nr_zones, (u64)dev->zone_nr_sectors);
2427 dmz_dev_info(dev, " %u metadata zones",
2428 zmd->nr_meta_zones * 2);
2429 dmz_dev_info(dev, " %u data zones for %u chunks",
2430 zmd->nr_data_zones, zmd->nr_chunks);
2431 dmz_dev_info(dev, " %u random zones (%u unmapped)",
2432 zmd->nr_rnd, atomic_read(&zmd->unmap_nr_rnd));
2433 dmz_dev_info(dev, " %u sequential zones (%u unmapped)",
2434 zmd->nr_seq, atomic_read(&zmd->unmap_nr_seq));
2435 dmz_dev_info(dev, " %u reserved sequential data zones",
2436 zmd->nr_reserved_seq);
2437
2438 dmz_dev_debug(dev, "Format:");
2439 dmz_dev_debug(dev, "%u metadata blocks per set (%u max cache)",
2440 zmd->nr_meta_blocks, zmd->max_nr_mblks);
2441 dmz_dev_debug(dev, " %u data zone mapping blocks",
2442 zmd->nr_map_blocks);
2443 dmz_dev_debug(dev, " %u bitmap blocks",
2444 zmd->nr_bitmap_blocks);
2445
2446 *metadata = zmd;
2447
2448 return 0;
2449err:
2450 dmz_cleanup_metadata(zmd);
2451 kfree(zmd);
2452 *metadata = NULL;
2453
2454 return ret;
2455}
2456
2457/*
2458 * Cleanup the zoned metadata resources.
2459 */
2460void dmz_dtr_metadata(struct dmz_metadata *zmd)
2461{
2462 unregister_shrinker(&zmd->mblk_shrinker);
2463 dmz_cleanup_metadata(zmd);
2464 kfree(zmd);
2465}
2466
2467/*
2468 * Check zone information on resume.
2469 */
2470int dmz_resume_metadata(struct dmz_metadata *zmd)
2471{
2472 struct dmz_dev *dev = zmd->dev;
2473 struct dm_zone *zone;
2474 sector_t wp_block;
2475 unsigned int i;
2476 int ret;
2477
2478 /* Check zones */
2479 for (i = 0; i < dev->nr_zones; i++) {
2480 zone = dmz_get(zmd, i);
2481 if (!zone) {
2482 dmz_dev_err(dev, "Unable to get zone %u", i);
2483 return -EIO;
2484 }
2485
2486 wp_block = zone->wp_block;
2487
2488 ret = dmz_update_zone(zmd, zone);
2489 if (ret) {
2490 dmz_dev_err(dev, "Broken zone %u", i);
2491 return ret;
2492 }
2493
2494 if (dmz_is_offline(zone)) {
2495 dmz_dev_warn(dev, "Zone %u is offline", i);
2496 continue;
2497 }
2498
2499 /* Check write pointer */
2500 if (!dmz_is_seq(zone))
2501 zone->wp_block = 0;
2502 else if (zone->wp_block != wp_block) {
2503 dmz_dev_err(dev, "Zone %u: Invalid wp (%llu / %llu)",
2504 i, (u64)zone->wp_block, (u64)wp_block);
2505 zone->wp_block = wp_block;
2506 dmz_invalidate_blocks(zmd, zone, zone->wp_block,
2507 dev->zone_nr_blocks - zone->wp_block);
2508 }
2509 }
2510
2511 return 0;
2512}