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