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gpio: rcar: Fix runtime PM imbalance on error
[linux/fpc-iii.git] / drivers / md / dm-zoned-metadata.c
blob369de15c4e80cc0b0245ded032b8d3789bb915be
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 1
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 */
41 struct 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 /* Padding to full 512B sector */
73 u8 reserved[464]; /* 512 */
74 };
75
76 /*
77 * Chunk mapping entry: entries are indexed by chunk number
78 * and give the zone ID (dzone_id) mapping the chunk on disk.
79 * This zone may be sequential or random. If it is a sequential
80 * zone, a second zone (bzone_id) used as a write buffer may
81 * also be specified. This second zone will always be a randomly
82 * writeable zone.
83 */
84 struct dmz_map {
85 __le32 dzone_id;
86 __le32 bzone_id;
87 };
88
89 /*
90 * Chunk mapping table metadata: 512 8-bytes entries per 4KB block.
91 */
92 #define DMZ_MAP_ENTRIES (DMZ_BLOCK_SIZE / sizeof(struct dmz_map))
93 #define DMZ_MAP_ENTRIES_SHIFT (ilog2(DMZ_MAP_ENTRIES))
94 #define DMZ_MAP_ENTRIES_MASK (DMZ_MAP_ENTRIES - 1)
95 #define DMZ_MAP_UNMAPPED UINT_MAX
96
97 /*
98 * Meta data block descriptor (for cached metadata blocks).
99 */
100 struct dmz_mblock {
101 struct rb_node node;
102 struct list_head link;
103 sector_t no;
104 unsigned int ref;
105 unsigned long state;
106 struct page *page;
107 void *data;
108 };
109
110 /*
111 * Metadata block state flags.
112 */
113 enum {
114 DMZ_META_DIRTY,
115 DMZ_META_READING,
116 DMZ_META_WRITING,
117 DMZ_META_ERROR,
118 };
119
120 /*
121 * Super block information (one per metadata set).
122 */
123 struct dmz_sb {
124 sector_t block;
125 struct dmz_mblock *mblk;
126 struct dmz_super *sb;
127 };
128
129 /*
130 * In-memory metadata.
131 */
132 struct dmz_metadata {
133 struct dmz_dev *dev;
134
135 sector_t zone_bitmap_size;
136 unsigned int zone_nr_bitmap_blocks;
137 unsigned int zone_bits_per_mblk;
138
139 unsigned int nr_bitmap_blocks;
140 unsigned int nr_map_blocks;
141
142 unsigned int nr_useable_zones;
143 unsigned int nr_meta_blocks;
144 unsigned int nr_meta_zones;
145 unsigned int nr_data_zones;
146 unsigned int nr_rnd_zones;
147 unsigned int nr_reserved_seq;
148 unsigned int nr_chunks;
149
150 /* Zone information array */
151 struct dm_zone *zones;
152
153 struct dm_zone *sb_zone;
154 struct dmz_sb sb[2];
155 unsigned int mblk_primary;
156 u64 sb_gen;
157 unsigned int min_nr_mblks;
158 unsigned int max_nr_mblks;
159 atomic_t nr_mblks;
160 struct rw_semaphore mblk_sem;
161 struct mutex mblk_flush_lock;
162 spinlock_t mblk_lock;
163 struct rb_root mblk_rbtree;
164 struct list_head mblk_lru_list;
165 struct list_head mblk_dirty_list;
166 struct shrinker mblk_shrinker;
167
168 /* Zone allocation management */
169 struct mutex map_lock;
170 struct dmz_mblock **map_mblk;
171 unsigned int nr_rnd;
172 atomic_t unmap_nr_rnd;
173 struct list_head unmap_rnd_list;
174 struct list_head map_rnd_list;
175
176 unsigned int nr_seq;
177 atomic_t unmap_nr_seq;
178 struct list_head unmap_seq_list;
179 struct list_head map_seq_list;
180
181 atomic_t nr_reserved_seq_zones;
182 struct list_head reserved_seq_zones_list;
183
184 wait_queue_head_t free_wq;
185 };
186
187 /*
188 * Various accessors
189 */
190 unsigned int dmz_id(struct dmz_metadata *zmd, struct dm_zone *zone)
191 {
192 return ((unsigned int)(zone - zmd->zones));
193 }
194
195 sector_t dmz_start_sect(struct dmz_metadata *zmd, struct dm_zone *zone)
196 {
197 return (sector_t)dmz_id(zmd, zone) << zmd->dev->zone_nr_sectors_shift;
198 }
199
200 sector_t dmz_start_block(struct dmz_metadata *zmd, struct dm_zone *zone)
201 {
202 return (sector_t)dmz_id(zmd, zone) << zmd->dev->zone_nr_blocks_shift;
203 }
204
205 unsigned int dmz_nr_chunks(struct dmz_metadata *zmd)
206 {
207 return zmd->nr_chunks;
208 }
209
210 unsigned int dmz_nr_rnd_zones(struct dmz_metadata *zmd)
211 {
212 return zmd->nr_rnd;
213 }
214
215 unsigned int dmz_nr_unmap_rnd_zones(struct dmz_metadata *zmd)
216 {
217 return atomic_read(&zmd->unmap_nr_rnd);
218 }
219
220 /*
221 * Lock/unlock mapping table.
222 * The map lock also protects all the zone lists.
223 */
224 void dmz_lock_map(struct dmz_metadata *zmd)
225 {
226 mutex_lock(&zmd->map_lock);
227 }
228
229 void dmz_unlock_map(struct dmz_metadata *zmd)
230 {
231 mutex_unlock(&zmd->map_lock);
232 }
233
234 /*
235 * Lock/unlock metadata access. This is a "read" lock on a semaphore
236 * that prevents metadata flush from running while metadata are being
237 * modified. The actual metadata write mutual exclusion is achieved with
238 * the map lock and zone state management (active and reclaim state are
239 * mutually exclusive).
240 */
241 void dmz_lock_metadata(struct dmz_metadata *zmd)
242 {
243 down_read(&zmd->mblk_sem);
244 }
245
246 void dmz_unlock_metadata(struct dmz_metadata *zmd)
247 {
248 up_read(&zmd->mblk_sem);
249 }
250
251 /*
252 * Lock/unlock flush: prevent concurrent executions
253 * of dmz_flush_metadata as well as metadata modification in reclaim
254 * while flush is being executed.
255 */
256 void dmz_lock_flush(struct dmz_metadata *zmd)
257 {
258 mutex_lock(&zmd->mblk_flush_lock);
259 }
260
261 void dmz_unlock_flush(struct dmz_metadata *zmd)
262 {
263 mutex_unlock(&zmd->mblk_flush_lock);
264 }
265
266 /*
267 * Allocate a metadata block.
268 */
269 static struct dmz_mblock *dmz_alloc_mblock(struct dmz_metadata *zmd,
270 sector_t mblk_no)
271 {
272 struct dmz_mblock *mblk = NULL;
273
274 /* See if we can reuse cached blocks */
275 if (zmd->max_nr_mblks && atomic_read(&zmd->nr_mblks) > zmd->max_nr_mblks) {
276 spin_lock(&zmd->mblk_lock);
277 mblk = list_first_entry_or_null(&zmd->mblk_lru_list,
278 struct dmz_mblock, link);
279 if (mblk) {
280 list_del_init(&mblk->link);
281 rb_erase(&mblk->node, &zmd->mblk_rbtree);
282 mblk->no = mblk_no;
283 }
284 spin_unlock(&zmd->mblk_lock);
285 if (mblk)
286 return mblk;
287 }
288
289 /* Allocate a new block */
290 mblk = kmalloc(sizeof(struct dmz_mblock), GFP_NOIO);
291 if (!mblk)
292 return NULL;
293
294 mblk->page = alloc_page(GFP_NOIO);
295 if (!mblk->page) {
296 kfree(mblk);
297 return NULL;
298 }
299
300 RB_CLEAR_NODE(&mblk->node);
301 INIT_LIST_HEAD(&mblk->link);
302 mblk->ref = 0;
303 mblk->state = 0;
304 mblk->no = mblk_no;
305 mblk->data = page_address(mblk->page);
306
307 atomic_inc(&zmd->nr_mblks);
308
309 return mblk;
310 }
311
312 /*
313 * Free a metadata block.
314 */
315 static void dmz_free_mblock(struct dmz_metadata *zmd, struct dmz_mblock *mblk)
316 {
317 __free_pages(mblk->page, 0);
318 kfree(mblk);
319
320 atomic_dec(&zmd->nr_mblks);
321 }
322
323 /*
324 * Insert a metadata block in the rbtree.
325 */
326 static void dmz_insert_mblock(struct dmz_metadata *zmd, struct dmz_mblock *mblk)
327 {
328 struct rb_root *root = &zmd->mblk_rbtree;
329 struct rb_node **new = &(root->rb_node), *parent = NULL;
330 struct dmz_mblock *b;
331
332 /* Figure out where to put the new node */
333 while (*new) {
334 b = container_of(*new, struct dmz_mblock, node);
335 parent = *new;
336 new = (b->no < mblk->no) ? &((*new)->rb_left) : &((*new)->rb_right);
337 }
338
339 /* Add new node and rebalance tree */
340 rb_link_node(&mblk->node, parent, new);
341 rb_insert_color(&mblk->node, root);
342 }
343
344 /*
345 * Lookup a metadata block in the rbtree. If the block is found, increment
346 * its reference count.
347 */
348 static struct dmz_mblock *dmz_get_mblock_fast(struct dmz_metadata *zmd,
349 sector_t mblk_no)
350 {
351 struct rb_root *root = &zmd->mblk_rbtree;
352 struct rb_node *node = root->rb_node;
353 struct dmz_mblock *mblk;
354
355 while (node) {
356 mblk = container_of(node, struct dmz_mblock, node);
357 if (mblk->no == mblk_no) {
358 /*
359 * If this is the first reference to the block,
360 * remove it from the LRU list.
361 */
362 mblk->ref++;
363 if (mblk->ref == 1 &&
364 !test_bit(DMZ_META_DIRTY, &mblk->state))
365 list_del_init(&mblk->link);
366 return mblk;
367 }
368 node = (mblk->no < mblk_no) ? node->rb_left : node->rb_right;
369 }
370
371 return NULL;
372 }
373
374 /*
375 * Metadata block BIO end callback.
376 */
377 static void dmz_mblock_bio_end_io(struct bio *bio)
378 {
379 struct dmz_mblock *mblk = bio->bi_private;
380 int flag;
381
382 if (bio->bi_status)
383 set_bit(DMZ_META_ERROR, &mblk->state);
384
385 if (bio_op(bio) == REQ_OP_WRITE)
386 flag = DMZ_META_WRITING;
387 else
388 flag = DMZ_META_READING;
389
390 clear_bit_unlock(flag, &mblk->state);
391 smp_mb__after_atomic();
392 wake_up_bit(&mblk->state, flag);
393
394 bio_put(bio);
395 }
396
397 /*
398 * Read an uncached metadata block from disk and add it to the cache.
399 */
400 static struct dmz_mblock *dmz_get_mblock_slow(struct dmz_metadata *zmd,
401 sector_t mblk_no)
402 {
403 struct dmz_mblock *mblk, *m;
404 sector_t block = zmd->sb[zmd->mblk_primary].block + mblk_no;
405 struct bio *bio;
406
407 if (dmz_bdev_is_dying(zmd->dev))
408 return ERR_PTR(-EIO);
409
410 /* Get a new block and a BIO to read it */
411 mblk = dmz_alloc_mblock(zmd, mblk_no);
412 if (!mblk)
413 return ERR_PTR(-ENOMEM);
414
415 bio = bio_alloc(GFP_NOIO, 1);
416 if (!bio) {
417 dmz_free_mblock(zmd, mblk);
418 return ERR_PTR(-ENOMEM);
419 }
420
421 spin_lock(&zmd->mblk_lock);
422
423 /*
424 * Make sure that another context did not start reading
425 * the block already.
426 */
427 m = dmz_get_mblock_fast(zmd, mblk_no);
428 if (m) {
429 spin_unlock(&zmd->mblk_lock);
430 dmz_free_mblock(zmd, mblk);
431 bio_put(bio);
432 return m;
433 }
434
435 mblk->ref++;
436 set_bit(DMZ_META_READING, &mblk->state);
437 dmz_insert_mblock(zmd, mblk);
438
439 spin_unlock(&zmd->mblk_lock);
440
441 /* Submit read BIO */
442 bio->bi_iter.bi_sector = dmz_blk2sect(block);
443 bio_set_dev(bio, zmd->dev->bdev);
444 bio->bi_private = mblk;
445 bio->bi_end_io = dmz_mblock_bio_end_io;
446 bio_set_op_attrs(bio, REQ_OP_READ, REQ_META | REQ_PRIO);
447 bio_add_page(bio, mblk->page, DMZ_BLOCK_SIZE, 0);
448 submit_bio(bio);
449
450 return mblk;
451 }
452
453 /*
454 * Free metadata blocks.
455 */
456 static unsigned long dmz_shrink_mblock_cache(struct dmz_metadata *zmd,
457 unsigned long limit)
458 {
459 struct dmz_mblock *mblk;
460 unsigned long count = 0;
461
462 if (!zmd->max_nr_mblks)
463 return 0;
464
465 while (!list_empty(&zmd->mblk_lru_list) &&
466 atomic_read(&zmd->nr_mblks) > zmd->min_nr_mblks &&
467 count < limit) {
468 mblk = list_first_entry(&zmd->mblk_lru_list,
469 struct dmz_mblock, link);
470 list_del_init(&mblk->link);
471 rb_erase(&mblk->node, &zmd->mblk_rbtree);
472 dmz_free_mblock(zmd, mblk);
473 count++;
474 }
475
476 return count;
477 }
478
479 /*
480 * For mblock shrinker: get the number of unused metadata blocks in the cache.
481 */
482 static unsigned long dmz_mblock_shrinker_count(struct shrinker *shrink,
483 struct shrink_control *sc)
484 {
485 struct dmz_metadata *zmd = container_of(shrink, struct dmz_metadata, mblk_shrinker);
486
487 return atomic_read(&zmd->nr_mblks);
488 }
489
490 /*
491 * For mblock shrinker: scan unused metadata blocks and shrink the cache.
492 */
493 static unsigned long dmz_mblock_shrinker_scan(struct shrinker *shrink,
494 struct shrink_control *sc)
495 {
496 struct dmz_metadata *zmd = container_of(shrink, struct dmz_metadata, mblk_shrinker);
497 unsigned long count;
498
499 spin_lock(&zmd->mblk_lock);
500 count = dmz_shrink_mblock_cache(zmd, sc->nr_to_scan);
501 spin_unlock(&zmd->mblk_lock);
502
503 return count ? count : SHRINK_STOP;
504 }
505
506 /*
507 * Release a metadata block.
508 */
509 static void dmz_release_mblock(struct dmz_metadata *zmd,
510 struct dmz_mblock *mblk)
511 {
512
513 if (!mblk)
514 return;
515
516 spin_lock(&zmd->mblk_lock);
517
518 mblk->ref--;
519 if (mblk->ref == 0) {
520 if (test_bit(DMZ_META_ERROR, &mblk->state)) {
521 rb_erase(&mblk->node, &zmd->mblk_rbtree);
522 dmz_free_mblock(zmd, mblk);
523 } else if (!test_bit(DMZ_META_DIRTY, &mblk->state)) {
524 list_add_tail(&mblk->link, &zmd->mblk_lru_list);
525 dmz_shrink_mblock_cache(zmd, 1);
526 }
527 }
528
529 spin_unlock(&zmd->mblk_lock);
530 }
531
532 /*
533 * Get a metadata block from the rbtree. If the block
534 * is not present, read it from disk.
535 */
536 static struct dmz_mblock *dmz_get_mblock(struct dmz_metadata *zmd,
537 sector_t mblk_no)
538 {
539 struct dmz_mblock *mblk;
540
541 /* Check rbtree */
542 spin_lock(&zmd->mblk_lock);
543 mblk = dmz_get_mblock_fast(zmd, mblk_no);
544 spin_unlock(&zmd->mblk_lock);
545
546 if (!mblk) {
547 /* Cache miss: read the block from disk */
548 mblk = dmz_get_mblock_slow(zmd, mblk_no);
549 if (IS_ERR(mblk))
550 return mblk;
551 }
552
553 /* Wait for on-going read I/O and check for error */
554 wait_on_bit_io(&mblk->state, DMZ_META_READING,
555 TASK_UNINTERRUPTIBLE);
556 if (test_bit(DMZ_META_ERROR, &mblk->state)) {
557 dmz_release_mblock(zmd, mblk);
558 dmz_check_bdev(zmd->dev);
559 return ERR_PTR(-EIO);
560 }
561
562 return mblk;
563 }
564
565 /*
566 * Mark a metadata block dirty.
567 */
568 static void dmz_dirty_mblock(struct dmz_metadata *zmd, struct dmz_mblock *mblk)
569 {
570 spin_lock(&zmd->mblk_lock);
571 if (!test_and_set_bit(DMZ_META_DIRTY, &mblk->state))
572 list_add_tail(&mblk->link, &zmd->mblk_dirty_list);
573 spin_unlock(&zmd->mblk_lock);
574 }
575
576 /*
577 * Issue a metadata block write BIO.
578 */
579 static int dmz_write_mblock(struct dmz_metadata *zmd, struct dmz_mblock *mblk,
580 unsigned int set)
581 {
582 sector_t block = zmd->sb[set].block + mblk->no;
583 struct bio *bio;
584
585 if (dmz_bdev_is_dying(zmd->dev))
586 return -EIO;
587
588 bio = bio_alloc(GFP_NOIO, 1);
589 if (!bio) {
590 set_bit(DMZ_META_ERROR, &mblk->state);
591 return -ENOMEM;
592 }
593
594 set_bit(DMZ_META_WRITING, &mblk->state);
595
596 bio->bi_iter.bi_sector = dmz_blk2sect(block);
597 bio_set_dev(bio, zmd->dev->bdev);
598 bio->bi_private = mblk;
599 bio->bi_end_io = dmz_mblock_bio_end_io;
600 bio_set_op_attrs(bio, REQ_OP_WRITE, REQ_META | REQ_PRIO);
601 bio_add_page(bio, mblk->page, DMZ_BLOCK_SIZE, 0);
602 submit_bio(bio);
603
604 return 0;
605 }
606
607 /*
608 * Read/write a metadata block.
609 */
610 static int dmz_rdwr_block(struct dmz_metadata *zmd, int op, sector_t block,
611 struct page *page)
612 {
613 struct bio *bio;
614 int ret;
615
616 if (dmz_bdev_is_dying(zmd->dev))
617 return -EIO;
618
619 bio = bio_alloc(GFP_NOIO, 1);
620 if (!bio)
621 return -ENOMEM;
622
623 bio->bi_iter.bi_sector = dmz_blk2sect(block);
624 bio_set_dev(bio, zmd->dev->bdev);
625 bio_set_op_attrs(bio, op, REQ_SYNC | REQ_META | REQ_PRIO);
626 bio_add_page(bio, page, DMZ_BLOCK_SIZE, 0);
627 ret = submit_bio_wait(bio);
628 bio_put(bio);
629
630 if (ret)
631 dmz_check_bdev(zmd->dev);
632 return ret;
633 }
634
635 /*
636 * Write super block of the specified metadata set.
637 */
638 static int dmz_write_sb(struct dmz_metadata *zmd, unsigned int set)
639 {
640 sector_t block = zmd->sb[set].block;
641 struct dmz_mblock *mblk = zmd->sb[set].mblk;
642 struct dmz_super *sb = zmd->sb[set].sb;
643 u64 sb_gen = zmd->sb_gen + 1;
644 int ret;
645
646 sb->magic = cpu_to_le32(DMZ_MAGIC);
647 sb->version = cpu_to_le32(DMZ_META_VER);
648
649 sb->gen = cpu_to_le64(sb_gen);
650
651 sb->sb_block = cpu_to_le64(block);
652 sb->nr_meta_blocks = cpu_to_le32(zmd->nr_meta_blocks);
653 sb->nr_reserved_seq = cpu_to_le32(zmd->nr_reserved_seq);
654 sb->nr_chunks = cpu_to_le32(zmd->nr_chunks);
655
656 sb->nr_map_blocks = cpu_to_le32(zmd->nr_map_blocks);
657 sb->nr_bitmap_blocks = cpu_to_le32(zmd->nr_bitmap_blocks);
658
659 sb->crc = 0;
660 sb->crc = cpu_to_le32(crc32_le(sb_gen, (unsigned char *)sb, DMZ_BLOCK_SIZE));
661
662 ret = dmz_rdwr_block(zmd, REQ_OP_WRITE, block, mblk->page);
663 if (ret == 0)
664 ret = blkdev_issue_flush(zmd->dev->bdev, GFP_NOIO, NULL);
665
666 return ret;
667 }
668
669 /*
670 * Write dirty metadata blocks to the specified set.
671 */
672 static int dmz_write_dirty_mblocks(struct dmz_metadata *zmd,
673 struct list_head *write_list,
674 unsigned int set)
675 {
676 struct dmz_mblock *mblk;
677 struct blk_plug plug;
678 int ret = 0, nr_mblks_submitted = 0;
679
680 /* Issue writes */
681 blk_start_plug(&plug);
682 list_for_each_entry(mblk, write_list, link) {
683 ret = dmz_write_mblock(zmd, mblk, set);
684 if (ret)
685 break;
686 nr_mblks_submitted++;
687 }
688 blk_finish_plug(&plug);
689
690 /* Wait for completion */
691 list_for_each_entry(mblk, write_list, link) {
692 if (!nr_mblks_submitted)
693 break;
694 wait_on_bit_io(&mblk->state, DMZ_META_WRITING,
695 TASK_UNINTERRUPTIBLE);
696 if (test_bit(DMZ_META_ERROR, &mblk->state)) {
697 clear_bit(DMZ_META_ERROR, &mblk->state);
698 dmz_check_bdev(zmd->dev);
699 ret = -EIO;
700 }
701 nr_mblks_submitted--;
702 }
703
704 /* Flush drive cache (this will also sync data) */
705 if (ret == 0)
706 ret = blkdev_issue_flush(zmd->dev->bdev, GFP_NOIO, NULL);
707
708 return ret;
709 }
710
711 /*
712 * Log dirty metadata blocks.
713 */
714 static int dmz_log_dirty_mblocks(struct dmz_metadata *zmd,
715 struct list_head *write_list)
716 {
717 unsigned int log_set = zmd->mblk_primary ^ 0x1;
718 int ret;
719
720 /* Write dirty blocks to the log */
721 ret = dmz_write_dirty_mblocks(zmd, write_list, log_set);
722 if (ret)
723 return ret;
724
725 /*
726 * No error so far: now validate the log by updating the
727 * log index super block generation.
728 */
729 ret = dmz_write_sb(zmd, log_set);
730 if (ret)
731 return ret;
732
733 return 0;
734 }
735
736 /*
737 * Flush dirty metadata blocks.
738 */
739 int dmz_flush_metadata(struct dmz_metadata *zmd)
740 {
741 struct dmz_mblock *mblk;
742 struct list_head write_list;
743 int ret;
744
745 if (WARN_ON(!zmd))
746 return 0;
747
748 INIT_LIST_HEAD(&write_list);
749
750 /*
751 * Make sure that metadata blocks are stable before logging: take
752 * the write lock on the metadata semaphore to prevent target BIOs
753 * from modifying metadata.
754 */
755 down_write(&zmd->mblk_sem);
756
757 /*
758 * This is called from the target flush work and reclaim work.
759 * Concurrent execution is not allowed.
760 */
761 dmz_lock_flush(zmd);
762
763 if (dmz_bdev_is_dying(zmd->dev)) {
764 ret = -EIO;
765 goto out;
766 }
767
768 /* Get dirty blocks */
769 spin_lock(&zmd->mblk_lock);
770 list_splice_init(&zmd->mblk_dirty_list, &write_list);
771 spin_unlock(&zmd->mblk_lock);
772
773 /* If there are no dirty metadata blocks, just flush the device cache */
774 if (list_empty(&write_list)) {
775 ret = blkdev_issue_flush(zmd->dev->bdev, GFP_NOIO, NULL);
776 goto err;
777 }
778
779 /*
780 * The primary metadata set is still clean. Keep it this way until
781 * all updates are successful in the secondary set. That is, use
782 * the secondary set as a log.
783 */
784 ret = dmz_log_dirty_mblocks(zmd, &write_list);
785 if (ret)
786 goto err;
787
788 /*
789 * The log is on disk. It is now safe to update in place
790 * in the primary metadata set.
791 */
792 ret = dmz_write_dirty_mblocks(zmd, &write_list, zmd->mblk_primary);
793 if (ret)
794 goto err;
795
796 ret = dmz_write_sb(zmd, zmd->mblk_primary);
797 if (ret)
798 goto err;
799
800 while (!list_empty(&write_list)) {
801 mblk = list_first_entry(&write_list, struct dmz_mblock, link);
802 list_del_init(&mblk->link);
803
804 spin_lock(&zmd->mblk_lock);
805 clear_bit(DMZ_META_DIRTY, &mblk->state);
806 if (mblk->ref == 0)
807 list_add_tail(&mblk->link, &zmd->mblk_lru_list);
808 spin_unlock(&zmd->mblk_lock);
809 }
810
811 zmd->sb_gen++;
812 out:
813 dmz_unlock_flush(zmd);
814 up_write(&zmd->mblk_sem);
815
816 return ret;
817
818 err:
819 if (!list_empty(&write_list)) {
820 spin_lock(&zmd->mblk_lock);
821 list_splice(&write_list, &zmd->mblk_dirty_list);
822 spin_unlock(&zmd->mblk_lock);
823 }
824 if (!dmz_check_bdev(zmd->dev))
825 ret = -EIO;
826 goto out;
827 }
828
829 /*
830 * Check super block.
831 */
832 static int dmz_check_sb(struct dmz_metadata *zmd, struct dmz_super *sb)
833 {
834 unsigned int nr_meta_zones, nr_data_zones;
835 struct dmz_dev *dev = zmd->dev;
836 u32 crc, stored_crc;
837 u64 gen;
838
839 gen = le64_to_cpu(sb->gen);
840 stored_crc = le32_to_cpu(sb->crc);
841 sb->crc = 0;
842 crc = crc32_le(gen, (unsigned char *)sb, DMZ_BLOCK_SIZE);
843 if (crc != stored_crc) {
844 dmz_dev_err(dev, "Invalid checksum (needed 0x%08x, got 0x%08x)",
845 crc, stored_crc);
846 return -ENXIO;
847 }
848
849 if (le32_to_cpu(sb->magic) != DMZ_MAGIC) {
850 dmz_dev_err(dev, "Invalid meta magic (needed 0x%08x, got 0x%08x)",
851 DMZ_MAGIC, le32_to_cpu(sb->magic));
852 return -ENXIO;
853 }
854
855 if (le32_to_cpu(sb->version) != DMZ_META_VER) {
856 dmz_dev_err(dev, "Invalid meta version (needed %d, got %d)",
857 DMZ_META_VER, le32_to_cpu(sb->version));
858 return -ENXIO;
859 }
860
861 nr_meta_zones = (le32_to_cpu(sb->nr_meta_blocks) + dev->zone_nr_blocks - 1)
862 >> dev->zone_nr_blocks_shift;
863 if (!nr_meta_zones ||
864 nr_meta_zones >= zmd->nr_rnd_zones) {
865 dmz_dev_err(dev, "Invalid number of metadata blocks");
866 return -ENXIO;
867 }
868
869 if (!le32_to_cpu(sb->nr_reserved_seq) ||
870 le32_to_cpu(sb->nr_reserved_seq) >= (zmd->nr_useable_zones - nr_meta_zones)) {
871 dmz_dev_err(dev, "Invalid number of reserved sequential zones");
872 return -ENXIO;
873 }
874
875 nr_data_zones = zmd->nr_useable_zones -
876 (nr_meta_zones * 2 + le32_to_cpu(sb->nr_reserved_seq));
877 if (le32_to_cpu(sb->nr_chunks) > nr_data_zones) {
878 dmz_dev_err(dev, "Invalid number of chunks %u / %u",
879 le32_to_cpu(sb->nr_chunks), nr_data_zones);
880 return -ENXIO;
881 }
882
883 /* OK */
884 zmd->nr_meta_blocks = le32_to_cpu(sb->nr_meta_blocks);
885 zmd->nr_reserved_seq = le32_to_cpu(sb->nr_reserved_seq);
886 zmd->nr_chunks = le32_to_cpu(sb->nr_chunks);
887 zmd->nr_map_blocks = le32_to_cpu(sb->nr_map_blocks);
888 zmd->nr_bitmap_blocks = le32_to_cpu(sb->nr_bitmap_blocks);
889 zmd->nr_meta_zones = nr_meta_zones;
890 zmd->nr_data_zones = nr_data_zones;
891
892 return 0;
893 }
894
895 /*
896 * Read the first or second super block from disk.
897 */
898 static int dmz_read_sb(struct dmz_metadata *zmd, unsigned int set)
899 {
900 return dmz_rdwr_block(zmd, REQ_OP_READ, zmd->sb[set].block,
901 zmd->sb[set].mblk->page);
902 }
903
904 /*
905 * Determine the position of the secondary super blocks on disk.
906 * This is used only if a corruption of the primary super block
907 * is detected.
908 */
909 static int dmz_lookup_secondary_sb(struct dmz_metadata *zmd)
910 {
911 unsigned int zone_nr_blocks = zmd->dev->zone_nr_blocks;
912 struct dmz_mblock *mblk;
913 int i;
914
915 /* Allocate a block */
916 mblk = dmz_alloc_mblock(zmd, 0);
917 if (!mblk)
918 return -ENOMEM;
919
920 zmd->sb[1].mblk = mblk;
921 zmd->sb[1].sb = mblk->data;
922
923 /* Bad first super block: search for the second one */
924 zmd->sb[1].block = zmd->sb[0].block + zone_nr_blocks;
925 for (i = 0; i < zmd->nr_rnd_zones - 1; i++) {
926 if (dmz_read_sb(zmd, 1) != 0)
927 break;
928 if (le32_to_cpu(zmd->sb[1].sb->magic) == DMZ_MAGIC)
929 return 0;
930 zmd->sb[1].block += zone_nr_blocks;
931 }
932
933 dmz_free_mblock(zmd, mblk);
934 zmd->sb[1].mblk = NULL;
935
936 return -EIO;
937 }
938
939 /*
940 * Read the first or second super block from disk.
941 */
942 static int dmz_get_sb(struct dmz_metadata *zmd, unsigned int set)
943 {
944 struct dmz_mblock *mblk;
945 int ret;
946
947 /* Allocate a block */
948 mblk = dmz_alloc_mblock(zmd, 0);
949 if (!mblk)
950 return -ENOMEM;
951
952 zmd->sb[set].mblk = mblk;
953 zmd->sb[set].sb = mblk->data;
954
955 /* Read super block */
956 ret = dmz_read_sb(zmd, set);
957 if (ret) {
958 dmz_free_mblock(zmd, mblk);
959 zmd->sb[set].mblk = NULL;
960 return ret;
961 }
962
963 return 0;
964 }
965
966 /*
967 * Recover a metadata set.
968 */
969 static int dmz_recover_mblocks(struct dmz_metadata *zmd, unsigned int dst_set)
970 {
971 unsigned int src_set = dst_set ^ 0x1;
972 struct page *page;
973 int i, ret;
974
975 dmz_dev_warn(zmd->dev, "Metadata set %u invalid: recovering", dst_set);
976
977 if (dst_set == 0)
978 zmd->sb[0].block = dmz_start_block(zmd, zmd->sb_zone);
979 else {
980 zmd->sb[1].block = zmd->sb[0].block +
981 (zmd->nr_meta_zones << zmd->dev->zone_nr_blocks_shift);
982 }
983
984 page = alloc_page(GFP_NOIO);
985 if (!page)
986 return -ENOMEM;
987
988 /* Copy metadata blocks */
989 for (i = 1; i < zmd->nr_meta_blocks; i++) {
990 ret = dmz_rdwr_block(zmd, REQ_OP_READ,
991 zmd->sb[src_set].block + i, page);
992 if (ret)
993 goto out;
994 ret = dmz_rdwr_block(zmd, REQ_OP_WRITE,
995 zmd->sb[dst_set].block + i, page);
996 if (ret)
997 goto out;
998 }
999
1000 /* Finalize with the super block */
1001 if (!zmd->sb[dst_set].mblk) {
1002 zmd->sb[dst_set].mblk = dmz_alloc_mblock(zmd, 0);
1003 if (!zmd->sb[dst_set].mblk) {
1004 ret = -ENOMEM;
1005 goto out;
1006 }
1007 zmd->sb[dst_set].sb = zmd->sb[dst_set].mblk->data;
1008 }
1009
1010 ret = dmz_write_sb(zmd, dst_set);
1011 out:
1012 __free_pages(page, 0);
1013
1014 return ret;
1015 }
1016
1017 /*
1018 * Get super block from disk.
1019 */
1020 static int dmz_load_sb(struct dmz_metadata *zmd)
1021 {
1022 bool sb_good[2] = {false, false};
1023 u64 sb_gen[2] = {0, 0};
1024 int ret;
1025
1026 /* Read and check the primary super block */
1027 zmd->sb[0].block = dmz_start_block(zmd, zmd->sb_zone);
1028 ret = dmz_get_sb(zmd, 0);
1029 if (ret) {
1030 dmz_dev_err(zmd->dev, "Read primary super block failed");
1031 return ret;
1032 }
1033
1034 ret = dmz_check_sb(zmd, zmd->sb[0].sb);
1035
1036 /* Read and check secondary super block */
1037 if (ret == 0) {
1038 sb_good[0] = true;
1039 zmd->sb[1].block = zmd->sb[0].block +
1040 (zmd->nr_meta_zones << zmd->dev->zone_nr_blocks_shift);
1041 ret = dmz_get_sb(zmd, 1);
1042 } else
1043 ret = dmz_lookup_secondary_sb(zmd);
1044
1045 if (ret) {
1046 dmz_dev_err(zmd->dev, "Read secondary super block failed");
1047 return ret;
1048 }
1049
1050 ret = dmz_check_sb(zmd, zmd->sb[1].sb);
1051 if (ret == 0)
1052 sb_good[1] = true;
1053
1054 /* Use highest generation sb first */
1055 if (!sb_good[0] && !sb_good[1]) {
1056 dmz_dev_err(zmd->dev, "No valid super block found");
1057 return -EIO;
1058 }
1059
1060 if (sb_good[0])
1061 sb_gen[0] = le64_to_cpu(zmd->sb[0].sb->gen);
1062 else
1063 ret = dmz_recover_mblocks(zmd, 0);
1064
1065 if (sb_good[1])
1066 sb_gen[1] = le64_to_cpu(zmd->sb[1].sb->gen);
1067 else
1068 ret = dmz_recover_mblocks(zmd, 1);
1069
1070 if (ret) {
1071 dmz_dev_err(zmd->dev, "Recovery failed");
1072 return -EIO;
1073 }
1074
1075 if (sb_gen[0] >= sb_gen[1]) {
1076 zmd->sb_gen = sb_gen[0];
1077 zmd->mblk_primary = 0;
1078 } else {
1079 zmd->sb_gen = sb_gen[1];
1080 zmd->mblk_primary = 1;
1081 }
1082
1083 dmz_dev_debug(zmd->dev, "Using super block %u (gen %llu)",
1084 zmd->mblk_primary, zmd->sb_gen);
1085
1086 return 0;
1087 }
1088
1089 /*
1090 * Initialize a zone descriptor.
1091 */
1092 static int dmz_init_zone(struct blk_zone *blkz, unsigned int idx, void *data)
1093 {
1094 struct dmz_metadata *zmd = data;
1095 struct dm_zone *zone = &zmd->zones[idx];
1096 struct dmz_dev *dev = zmd->dev;
1097
1098 /* Ignore the eventual last runt (smaller) zone */
1099 if (blkz->len != dev->zone_nr_sectors) {
1100 if (blkz->start + blkz->len == dev->capacity)
1101 return 0;
1102 return -ENXIO;
1103 }
1104
1105 INIT_LIST_HEAD(&zone->link);
1106 atomic_set(&zone->refcount, 0);
1107 zone->chunk = DMZ_MAP_UNMAPPED;
1108
1109 switch (blkz->type) {
1110 case BLK_ZONE_TYPE_CONVENTIONAL:
1111 set_bit(DMZ_RND, &zone->flags);
1112 break;
1113 case BLK_ZONE_TYPE_SEQWRITE_REQ:
1114 case BLK_ZONE_TYPE_SEQWRITE_PREF:
1115 set_bit(DMZ_SEQ, &zone->flags);
1116 break;
1117 default:
1118 return -ENXIO;
1119 }
1120
1121 if (dmz_is_rnd(zone))
1122 zone->wp_block = 0;
1123 else
1124 zone->wp_block = dmz_sect2blk(blkz->wp - blkz->start);
1125
1126 if (blkz->cond == BLK_ZONE_COND_OFFLINE)
1127 set_bit(DMZ_OFFLINE, &zone->flags);
1128 else if (blkz->cond == BLK_ZONE_COND_READONLY)
1129 set_bit(DMZ_READ_ONLY, &zone->flags);
1130 else {
1131 zmd->nr_useable_zones++;
1132 if (dmz_is_rnd(zone)) {
1133 zmd->nr_rnd_zones++;
1134 if (!zmd->sb_zone) {
1135 /* Super block zone */
1136 zmd->sb_zone = zone;
1137 }
1138 }
1139 }
1140
1141 return 0;
1142 }
1143
1144 /*
1145 * Free zones descriptors.
1146 */
1147 static void dmz_drop_zones(struct dmz_metadata *zmd)
1148 {
1149 kfree(zmd->zones);
1150 zmd->zones = NULL;
1151 }
1152
1153 /*
1154 * Allocate and initialize zone descriptors using the zone
1155 * information from disk.
1156 */
1157 static int dmz_init_zones(struct dmz_metadata *zmd)
1158 {
1159 struct dmz_dev *dev = zmd->dev;
1160 int ret;
1161
1162 /* Init */
1163 zmd->zone_bitmap_size = dev->zone_nr_blocks >> 3;
1164 zmd->zone_nr_bitmap_blocks =
1165 max_t(sector_t, 1, zmd->zone_bitmap_size >> DMZ_BLOCK_SHIFT);
1166 zmd->zone_bits_per_mblk = min_t(sector_t, dev->zone_nr_blocks,
1167 DMZ_BLOCK_SIZE_BITS);
1168
1169 /* Allocate zone array */
1170 zmd->zones = kcalloc(dev->nr_zones, sizeof(struct dm_zone), GFP_KERNEL);
1171 if (!zmd->zones)
1172 return -ENOMEM;
1173
1174 dmz_dev_info(dev, "Using %zu B for zone information",
1175 sizeof(struct dm_zone) * dev->nr_zones);
1176
1177 /*
1178 * Get zone information and initialize zone descriptors. At the same
1179 * time, determine where the super block should be: first block of the
1180 * first randomly writable zone.
1181 */
1182 ret = blkdev_report_zones(dev->bdev, 0, BLK_ALL_ZONES, dmz_init_zone,
1183 zmd);
1184 if (ret < 0) {
1185 dmz_drop_zones(zmd);
1186 return ret;
1187 }
1188
1189 return 0;
1190 }
1191
1192 static int dmz_update_zone_cb(struct blk_zone *blkz, unsigned int idx,
1193 void *data)
1194 {
1195 struct dm_zone *zone = data;
1196
1197 clear_bit(DMZ_OFFLINE, &zone->flags);
1198 clear_bit(DMZ_READ_ONLY, &zone->flags);
1199 if (blkz->cond == BLK_ZONE_COND_OFFLINE)
1200 set_bit(DMZ_OFFLINE, &zone->flags);
1201 else if (blkz->cond == BLK_ZONE_COND_READONLY)
1202 set_bit(DMZ_READ_ONLY, &zone->flags);
1203
1204 if (dmz_is_seq(zone))
1205 zone->wp_block = dmz_sect2blk(blkz->wp - blkz->start);
1206 else
1207 zone->wp_block = 0;
1208 return 0;
1209 }
1210
1211 /*
1212 * Update a zone information.
1213 */
1214 static int dmz_update_zone(struct dmz_metadata *zmd, struct dm_zone *zone)
1215 {
1216 unsigned int noio_flag;
1217 int ret;
1218
1219 /*
1220 * Get zone information from disk. Since blkdev_report_zones() uses
1221 * GFP_KERNEL by default for memory allocations, set the per-task
1222 * PF_MEMALLOC_NOIO flag so that all allocations are done as if
1223 * GFP_NOIO was specified.
1224 */
1225 noio_flag = memalloc_noio_save();
1226 ret = blkdev_report_zones(zmd->dev->bdev, dmz_start_sect(zmd, zone), 1,
1227 dmz_update_zone_cb, zone);
1228 memalloc_noio_restore(noio_flag);
1229
1230 if (ret == 0)
1231 ret = -EIO;
1232 if (ret < 0) {
1233 dmz_dev_err(zmd->dev, "Get zone %u report failed",
1234 dmz_id(zmd, zone));
1235 dmz_check_bdev(zmd->dev);
1236 return ret;
1237 }
1238
1239 return 0;
1240 }
1241
1242 /*
1243 * Check a zone write pointer position when the zone is marked
1244 * with the sequential write error flag.
1245 */
1246 static int dmz_handle_seq_write_err(struct dmz_metadata *zmd,
1247 struct dm_zone *zone)
1248 {
1249 unsigned int wp = 0;
1250 int ret;
1251
1252 wp = zone->wp_block;
1253 ret = dmz_update_zone(zmd, zone);
1254 if (ret)
1255 return ret;
1256
1257 dmz_dev_warn(zmd->dev, "Processing zone %u write error (zone wp %u/%u)",
1258 dmz_id(zmd, zone), zone->wp_block, wp);
1259
1260 if (zone->wp_block < wp) {
1261 dmz_invalidate_blocks(zmd, zone, zone->wp_block,
1262 wp - zone->wp_block);
1263 }
1264
1265 return 0;
1266 }
1267
1268 static struct dm_zone *dmz_get(struct dmz_metadata *zmd, unsigned int zone_id)
1269 {
1270 return &zmd->zones[zone_id];
1271 }
1272
1273 /*
1274 * Reset a zone write pointer.
1275 */
1276 static int dmz_reset_zone(struct dmz_metadata *zmd, struct dm_zone *zone)
1277 {
1278 int ret;
1279
1280 /*
1281 * Ignore offline zones, read only zones,
1282 * and conventional zones.
1283 */
1284 if (dmz_is_offline(zone) ||
1285 dmz_is_readonly(zone) ||
1286 dmz_is_rnd(zone))
1287 return 0;
1288
1289 if (!dmz_is_empty(zone) || dmz_seq_write_err(zone)) {
1290 struct dmz_dev *dev = zmd->dev;
1291
1292 ret = blkdev_zone_mgmt(dev->bdev, REQ_OP_ZONE_RESET,
1293 dmz_start_sect(zmd, zone),
1294 dev->zone_nr_sectors, GFP_NOIO);
1295 if (ret) {
1296 dmz_dev_err(dev, "Reset zone %u failed %d",
1297 dmz_id(zmd, zone), ret);
1298 return ret;
1299 }
1300 }
1301
1302 /* Clear write error bit and rewind write pointer position */
1303 clear_bit(DMZ_SEQ_WRITE_ERR, &zone->flags);
1304 zone->wp_block = 0;
1305
1306 return 0;
1307 }
1308
1309 static void dmz_get_zone_weight(struct dmz_metadata *zmd, struct dm_zone *zone);
1310
1311 /*
1312 * Initialize chunk mapping.
1313 */
1314 static int dmz_load_mapping(struct dmz_metadata *zmd)
1315 {
1316 struct dmz_dev *dev = zmd->dev;
1317 struct dm_zone *dzone, *bzone;
1318 struct dmz_mblock *dmap_mblk = NULL;
1319 struct dmz_map *dmap;
1320 unsigned int i = 0, e = 0, chunk = 0;
1321 unsigned int dzone_id;
1322 unsigned int bzone_id;
1323
1324 /* Metadata block array for the chunk mapping table */
1325 zmd->map_mblk = kcalloc(zmd->nr_map_blocks,
1326 sizeof(struct dmz_mblk *), GFP_KERNEL);
1327 if (!zmd->map_mblk)
1328 return -ENOMEM;
1329
1330 /* Get chunk mapping table blocks and initialize zone mapping */
1331 while (chunk < zmd->nr_chunks) {
1332 if (!dmap_mblk) {
1333 /* Get mapping block */
1334 dmap_mblk = dmz_get_mblock(zmd, i + 1);
1335 if (IS_ERR(dmap_mblk))
1336 return PTR_ERR(dmap_mblk);
1337 zmd->map_mblk[i] = dmap_mblk;
1338 dmap = (struct dmz_map *) dmap_mblk->data;
1339 i++;
1340 e = 0;
1341 }
1342
1343 /* Check data zone */
1344 dzone_id = le32_to_cpu(dmap[e].dzone_id);
1345 if (dzone_id == DMZ_MAP_UNMAPPED)
1346 goto next;
1347
1348 if (dzone_id >= dev->nr_zones) {
1349 dmz_dev_err(dev, "Chunk %u mapping: invalid data zone ID %u",
1350 chunk, dzone_id);
1351 return -EIO;
1352 }
1353
1354 dzone = dmz_get(zmd, dzone_id);
1355 set_bit(DMZ_DATA, &dzone->flags);
1356 dzone->chunk = chunk;
1357 dmz_get_zone_weight(zmd, dzone);
1358
1359 if (dmz_is_rnd(dzone))
1360 list_add_tail(&dzone->link, &zmd->map_rnd_list);
1361 else
1362 list_add_tail(&dzone->link, &zmd->map_seq_list);
1363
1364 /* Check buffer zone */
1365 bzone_id = le32_to_cpu(dmap[e].bzone_id);
1366 if (bzone_id == DMZ_MAP_UNMAPPED)
1367 goto next;
1368
1369 if (bzone_id >= dev->nr_zones) {
1370 dmz_dev_err(dev, "Chunk %u mapping: invalid buffer zone ID %u",
1371 chunk, bzone_id);
1372 return -EIO;
1373 }
1374
1375 bzone = dmz_get(zmd, bzone_id);
1376 if (!dmz_is_rnd(bzone)) {
1377 dmz_dev_err(dev, "Chunk %u mapping: invalid buffer zone %u",
1378 chunk, bzone_id);
1379 return -EIO;
1380 }
1381
1382 set_bit(DMZ_DATA, &bzone->flags);
1383 set_bit(DMZ_BUF, &bzone->flags);
1384 bzone->chunk = chunk;
1385 bzone->bzone = dzone;
1386 dzone->bzone = bzone;
1387 dmz_get_zone_weight(zmd, bzone);
1388 list_add_tail(&bzone->link, &zmd->map_rnd_list);
1389 next:
1390 chunk++;
1391 e++;
1392 if (e >= DMZ_MAP_ENTRIES)
1393 dmap_mblk = NULL;
1394 }
1395
1396 /*
1397 * At this point, only meta zones and mapped data zones were
1398 * fully initialized. All remaining zones are unmapped data
1399 * zones. Finish initializing those here.
1400 */
1401 for (i = 0; i < dev->nr_zones; i++) {
1402 dzone = dmz_get(zmd, i);
1403 if (dmz_is_meta(dzone))
1404 continue;
1405
1406 if (dmz_is_rnd(dzone))
1407 zmd->nr_rnd++;
1408 else
1409 zmd->nr_seq++;
1410
1411 if (dmz_is_data(dzone)) {
1412 /* Already initialized */
1413 continue;
1414 }
1415
1416 /* Unmapped data zone */
1417 set_bit(DMZ_DATA, &dzone->flags);
1418 dzone->chunk = DMZ_MAP_UNMAPPED;
1419 if (dmz_is_rnd(dzone)) {
1420 list_add_tail(&dzone->link, &zmd->unmap_rnd_list);
1421 atomic_inc(&zmd->unmap_nr_rnd);
1422 } else if (atomic_read(&zmd->nr_reserved_seq_zones) < zmd->nr_reserved_seq) {
1423 list_add_tail(&dzone->link, &zmd->reserved_seq_zones_list);
1424 atomic_inc(&zmd->nr_reserved_seq_zones);
1425 zmd->nr_seq--;
1426 } else {
1427 list_add_tail(&dzone->link, &zmd->unmap_seq_list);
1428 atomic_inc(&zmd->unmap_nr_seq);
1429 }
1430 }
1431
1432 return 0;
1433 }
1434
1435 /*
1436 * Set a data chunk mapping.
1437 */
1438 static void dmz_set_chunk_mapping(struct dmz_metadata *zmd, unsigned int chunk,
1439 unsigned int dzone_id, unsigned int bzone_id)
1440 {
1441 struct dmz_mblock *dmap_mblk = zmd->map_mblk[chunk >> DMZ_MAP_ENTRIES_SHIFT];
1442 struct dmz_map *dmap = (struct dmz_map *) dmap_mblk->data;
1443 int map_idx = chunk & DMZ_MAP_ENTRIES_MASK;
1444
1445 dmap[map_idx].dzone_id = cpu_to_le32(dzone_id);
1446 dmap[map_idx].bzone_id = cpu_to_le32(bzone_id);
1447 dmz_dirty_mblock(zmd, dmap_mblk);
1448 }
1449
1450 /*
1451 * The list of mapped zones is maintained in LRU order.
1452 * This rotates a zone at the end of its map list.
1453 */
1454 static void __dmz_lru_zone(struct dmz_metadata *zmd, struct dm_zone *zone)
1455 {
1456 if (list_empty(&zone->link))
1457 return;
1458
1459 list_del_init(&zone->link);
1460 if (dmz_is_seq(zone)) {
1461 /* LRU rotate sequential zone */
1462 list_add_tail(&zone->link, &zmd->map_seq_list);
1463 } else {
1464 /* LRU rotate random zone */
1465 list_add_tail(&zone->link, &zmd->map_rnd_list);
1466 }
1467 }
1468
1469 /*
1470 * The list of mapped random zones is maintained
1471 * in LRU order. This rotates a zone at the end of the list.
1472 */
1473 static void dmz_lru_zone(struct dmz_metadata *zmd, struct dm_zone *zone)
1474 {
1475 __dmz_lru_zone(zmd, zone);
1476 if (zone->bzone)
1477 __dmz_lru_zone(zmd, zone->bzone);
1478 }
1479
1480 /*
1481 * Wait for any zone to be freed.
1482 */
1483 static void dmz_wait_for_free_zones(struct dmz_metadata *zmd)
1484 {
1485 DEFINE_WAIT(wait);
1486
1487 prepare_to_wait(&zmd->free_wq, &wait, TASK_UNINTERRUPTIBLE);
1488 dmz_unlock_map(zmd);
1489 dmz_unlock_metadata(zmd);
1490
1491 io_schedule_timeout(HZ);
1492
1493 dmz_lock_metadata(zmd);
1494 dmz_lock_map(zmd);
1495 finish_wait(&zmd->free_wq, &wait);
1496 }
1497
1498 /*
1499 * Lock a zone for reclaim (set the zone RECLAIM bit).
1500 * Returns false if the zone cannot be locked or if it is already locked
1501 * and 1 otherwise.
1502 */
1503 int dmz_lock_zone_reclaim(struct dm_zone *zone)
1504 {
1505 /* Active zones cannot be reclaimed */
1506 if (dmz_is_active(zone))
1507 return 0;
1508
1509 return !test_and_set_bit(DMZ_RECLAIM, &zone->flags);
1510 }
1511
1512 /*
1513 * Clear a zone reclaim flag.
1514 */
1515 void dmz_unlock_zone_reclaim(struct dm_zone *zone)
1516 {
1517 WARN_ON(dmz_is_active(zone));
1518 WARN_ON(!dmz_in_reclaim(zone));
1519
1520 clear_bit_unlock(DMZ_RECLAIM, &zone->flags);
1521 smp_mb__after_atomic();
1522 wake_up_bit(&zone->flags, DMZ_RECLAIM);
1523 }
1524
1525 /*
1526 * Wait for a zone reclaim to complete.
1527 */
1528 static void dmz_wait_for_reclaim(struct dmz_metadata *zmd, struct dm_zone *zone)
1529 {
1530 dmz_unlock_map(zmd);
1531 dmz_unlock_metadata(zmd);
1532 wait_on_bit_timeout(&zone->flags, DMZ_RECLAIM, TASK_UNINTERRUPTIBLE, HZ);
1533 dmz_lock_metadata(zmd);
1534 dmz_lock_map(zmd);
1535 }
1536
1537 /*
1538 * Select a random write zone for reclaim.
1539 */
1540 static struct dm_zone *dmz_get_rnd_zone_for_reclaim(struct dmz_metadata *zmd)
1541 {
1542 struct dm_zone *dzone = NULL;
1543 struct dm_zone *zone;
1544
1545 if (list_empty(&zmd->map_rnd_list))
1546 return ERR_PTR(-EBUSY);
1547
1548 list_for_each_entry(zone, &zmd->map_rnd_list, link) {
1549 if (dmz_is_buf(zone))
1550 dzone = zone->bzone;
1551 else
1552 dzone = zone;
1553 if (dmz_lock_zone_reclaim(dzone))
1554 return dzone;
1555 }
1556
1557 return ERR_PTR(-EBUSY);
1558 }
1559
1560 /*
1561 * Select a buffered sequential zone for reclaim.
1562 */
1563 static struct dm_zone *dmz_get_seq_zone_for_reclaim(struct dmz_metadata *zmd)
1564 {
1565 struct dm_zone *zone;
1566
1567 if (list_empty(&zmd->map_seq_list))
1568 return ERR_PTR(-EBUSY);
1569
1570 list_for_each_entry(zone, &zmd->map_seq_list, link) {
1571 if (!zone->bzone)
1572 continue;
1573 if (dmz_lock_zone_reclaim(zone))
1574 return zone;
1575 }
1576
1577 return ERR_PTR(-EBUSY);
1578 }
1579
1580 /*
1581 * Select a zone for reclaim.
1582 */
1583 struct dm_zone *dmz_get_zone_for_reclaim(struct dmz_metadata *zmd)
1584 {
1585 struct dm_zone *zone;
1586
1587 /*
1588 * Search for a zone candidate to reclaim: 2 cases are possible.
1589 * (1) There is no free sequential zones. Then a random data zone
1590 * cannot be reclaimed. So choose a sequential zone to reclaim so
1591 * that afterward a random zone can be reclaimed.
1592 * (2) At least one free sequential zone is available, then choose
1593 * the oldest random zone (data or buffer) that can be locked.
1594 */
1595 dmz_lock_map(zmd);
1596 if (list_empty(&zmd->reserved_seq_zones_list))
1597 zone = dmz_get_seq_zone_for_reclaim(zmd);
1598 else
1599 zone = dmz_get_rnd_zone_for_reclaim(zmd);
1600 dmz_unlock_map(zmd);
1601
1602 return zone;
1603 }
1604
1605 /*
1606 * Get the zone mapping a chunk, if the chunk is mapped already.
1607 * If no mapping exist and the operation is WRITE, a zone is
1608 * allocated and used to map the chunk.
1609 * The zone returned will be set to the active state.
1610 */
1611 struct dm_zone *dmz_get_chunk_mapping(struct dmz_metadata *zmd, unsigned int chunk, int op)
1612 {
1613 struct dmz_mblock *dmap_mblk = zmd->map_mblk[chunk >> DMZ_MAP_ENTRIES_SHIFT];
1614 struct dmz_map *dmap = (struct dmz_map *) dmap_mblk->data;
1615 int dmap_idx = chunk & DMZ_MAP_ENTRIES_MASK;
1616 unsigned int dzone_id;
1617 struct dm_zone *dzone = NULL;
1618 int ret = 0;
1619
1620 dmz_lock_map(zmd);
1621 again:
1622 /* Get the chunk mapping */
1623 dzone_id = le32_to_cpu(dmap[dmap_idx].dzone_id);
1624 if (dzone_id == DMZ_MAP_UNMAPPED) {
1625 /*
1626 * Read or discard in unmapped chunks are fine. But for
1627 * writes, we need a mapping, so get one.
1628 */
1629 if (op != REQ_OP_WRITE)
1630 goto out;
1631
1632 /* Allocate a random zone */
1633 dzone = dmz_alloc_zone(zmd, DMZ_ALLOC_RND);
1634 if (!dzone) {
1635 if (dmz_bdev_is_dying(zmd->dev)) {
1636 dzone = ERR_PTR(-EIO);
1637 goto out;
1638 }
1639 dmz_wait_for_free_zones(zmd);
1640 goto again;
1641 }
1642
1643 dmz_map_zone(zmd, dzone, chunk);
1644
1645 } else {
1646 /* The chunk is already mapped: get the mapping zone */
1647 dzone = dmz_get(zmd, dzone_id);
1648 if (dzone->chunk != chunk) {
1649 dzone = ERR_PTR(-EIO);
1650 goto out;
1651 }
1652
1653 /* Repair write pointer if the sequential dzone has error */
1654 if (dmz_seq_write_err(dzone)) {
1655 ret = dmz_handle_seq_write_err(zmd, dzone);
1656 if (ret) {
1657 dzone = ERR_PTR(-EIO);
1658 goto out;
1659 }
1660 clear_bit(DMZ_SEQ_WRITE_ERR, &dzone->flags);
1661 }
1662 }
1663
1664 /*
1665 * If the zone is being reclaimed, the chunk mapping may change
1666 * to a different zone. So wait for reclaim and retry. Otherwise,
1667 * activate the zone (this will prevent reclaim from touching it).
1668 */
1669 if (dmz_in_reclaim(dzone)) {
1670 dmz_wait_for_reclaim(zmd, dzone);
1671 goto again;
1672 }
1673 dmz_activate_zone(dzone);
1674 dmz_lru_zone(zmd, dzone);
1675 out:
1676 dmz_unlock_map(zmd);
1677
1678 return dzone;
1679 }
1680
1681 /*
1682 * Write and discard change the block validity of data zones and their buffer
1683 * zones. Check here that valid blocks are still present. If all blocks are
1684 * invalid, the zones can be unmapped on the fly without waiting for reclaim
1685 * to do it.
1686 */
1687 void dmz_put_chunk_mapping(struct dmz_metadata *zmd, struct dm_zone *dzone)
1688 {
1689 struct dm_zone *bzone;
1690
1691 dmz_lock_map(zmd);
1692
1693 bzone = dzone->bzone;
1694 if (bzone) {
1695 if (dmz_weight(bzone))
1696 dmz_lru_zone(zmd, bzone);
1697 else {
1698 /* Empty buffer zone: reclaim it */
1699 dmz_unmap_zone(zmd, bzone);
1700 dmz_free_zone(zmd, bzone);
1701 bzone = NULL;
1702 }
1703 }
1704
1705 /* Deactivate the data zone */
1706 dmz_deactivate_zone(dzone);
1707 if (dmz_is_active(dzone) || bzone || dmz_weight(dzone))
1708 dmz_lru_zone(zmd, dzone);
1709 else {
1710 /* Unbuffered inactive empty data zone: reclaim it */
1711 dmz_unmap_zone(zmd, dzone);
1712 dmz_free_zone(zmd, dzone);
1713 }
1714
1715 dmz_unlock_map(zmd);
1716 }
1717
1718 /*
1719 * Allocate and map a random zone to buffer a chunk
1720 * already mapped to a sequential zone.
1721 */
1722 struct dm_zone *dmz_get_chunk_buffer(struct dmz_metadata *zmd,
1723 struct dm_zone *dzone)
1724 {
1725 struct dm_zone *bzone;
1726
1727 dmz_lock_map(zmd);
1728 again:
1729 bzone = dzone->bzone;
1730 if (bzone)
1731 goto out;
1732
1733 /* Allocate a random zone */
1734 bzone = dmz_alloc_zone(zmd, DMZ_ALLOC_RND);
1735 if (!bzone) {
1736 if (dmz_bdev_is_dying(zmd->dev)) {
1737 bzone = ERR_PTR(-EIO);
1738 goto out;
1739 }
1740 dmz_wait_for_free_zones(zmd);
1741 goto again;
1742 }
1743
1744 /* Update the chunk mapping */
1745 dmz_set_chunk_mapping(zmd, dzone->chunk, dmz_id(zmd, dzone),
1746 dmz_id(zmd, bzone));
1747
1748 set_bit(DMZ_BUF, &bzone->flags);
1749 bzone->chunk = dzone->chunk;
1750 bzone->bzone = dzone;
1751 dzone->bzone = bzone;
1752 list_add_tail(&bzone->link, &zmd->map_rnd_list);
1753 out:
1754 dmz_unlock_map(zmd);
1755
1756 return bzone;
1757 }
1758
1759 /*
1760 * Get an unmapped (free) zone.
1761 * This must be called with the mapping lock held.
1762 */
1763 struct dm_zone *dmz_alloc_zone(struct dmz_metadata *zmd, unsigned long flags)
1764 {
1765 struct list_head *list;
1766 struct dm_zone *zone;
1767
1768 if (flags & DMZ_ALLOC_RND)
1769 list = &zmd->unmap_rnd_list;
1770 else
1771 list = &zmd->unmap_seq_list;
1772 again:
1773 if (list_empty(list)) {
1774 /*
1775 * No free zone: if this is for reclaim, allow using the
1776 * reserved sequential zones.
1777 */
1778 if (!(flags & DMZ_ALLOC_RECLAIM) ||
1779 list_empty(&zmd->reserved_seq_zones_list))
1780 return NULL;
1781
1782 zone = list_first_entry(&zmd->reserved_seq_zones_list,
1783 struct dm_zone, link);
1784 list_del_init(&zone->link);
1785 atomic_dec(&zmd->nr_reserved_seq_zones);
1786 return zone;
1787 }
1788
1789 zone = list_first_entry(list, struct dm_zone, link);
1790 list_del_init(&zone->link);
1791
1792 if (dmz_is_rnd(zone))
1793 atomic_dec(&zmd->unmap_nr_rnd);
1794 else
1795 atomic_dec(&zmd->unmap_nr_seq);
1796
1797 if (dmz_is_offline(zone)) {
1798 dmz_dev_warn(zmd->dev, "Zone %u is offline", dmz_id(zmd, zone));
1799 zone = NULL;
1800 goto again;
1801 }
1802
1803 return zone;
1804 }
1805
1806 /*
1807 * Free a zone.
1808 * This must be called with the mapping lock held.
1809 */
1810 void dmz_free_zone(struct dmz_metadata *zmd, struct dm_zone *zone)
1811 {
1812 /* If this is a sequential zone, reset it */
1813 if (dmz_is_seq(zone))
1814 dmz_reset_zone(zmd, zone);
1815
1816 /* Return the zone to its type unmap list */
1817 if (dmz_is_rnd(zone)) {
1818 list_add_tail(&zone->link, &zmd->unmap_rnd_list);
1819 atomic_inc(&zmd->unmap_nr_rnd);
1820 } else if (atomic_read(&zmd->nr_reserved_seq_zones) <
1821 zmd->nr_reserved_seq) {
1822 list_add_tail(&zone->link, &zmd->reserved_seq_zones_list);
1823 atomic_inc(&zmd->nr_reserved_seq_zones);
1824 } else {
1825 list_add_tail(&zone->link, &zmd->unmap_seq_list);
1826 atomic_inc(&zmd->unmap_nr_seq);
1827 }
1828
1829 wake_up_all(&zmd->free_wq);
1830 }
1831
1832 /*
1833 * Map a chunk to a zone.
1834 * This must be called with the mapping lock held.
1835 */
1836 void dmz_map_zone(struct dmz_metadata *zmd, struct dm_zone *dzone,
1837 unsigned int chunk)
1838 {
1839 /* Set the chunk mapping */
1840 dmz_set_chunk_mapping(zmd, chunk, dmz_id(zmd, dzone),
1841 DMZ_MAP_UNMAPPED);
1842 dzone->chunk = chunk;
1843 if (dmz_is_rnd(dzone))
1844 list_add_tail(&dzone->link, &zmd->map_rnd_list);
1845 else
1846 list_add_tail(&dzone->link, &zmd->map_seq_list);
1847 }
1848
1849 /*
1850 * Unmap a zone.
1851 * This must be called with the mapping lock held.
1852 */
1853 void dmz_unmap_zone(struct dmz_metadata *zmd, struct dm_zone *zone)
1854 {
1855 unsigned int chunk = zone->chunk;
1856 unsigned int dzone_id;
1857
1858 if (chunk == DMZ_MAP_UNMAPPED) {
1859 /* Already unmapped */
1860 return;
1861 }
1862
1863 if (test_and_clear_bit(DMZ_BUF, &zone->flags)) {
1864 /*
1865 * Unmapping the chunk buffer zone: clear only
1866 * the chunk buffer mapping
1867 */
1868 dzone_id = dmz_id(zmd, zone->bzone);
1869 zone->bzone->bzone = NULL;
1870 zone->bzone = NULL;
1871
1872 } else {
1873 /*
1874 * Unmapping the chunk data zone: the zone must
1875 * not be buffered.
1876 */
1877 if (WARN_ON(zone->bzone)) {
1878 zone->bzone->bzone = NULL;
1879 zone->bzone = NULL;
1880 }
1881 dzone_id = DMZ_MAP_UNMAPPED;
1882 }
1883
1884 dmz_set_chunk_mapping(zmd, chunk, dzone_id, DMZ_MAP_UNMAPPED);
1885
1886 zone->chunk = DMZ_MAP_UNMAPPED;
1887 list_del_init(&zone->link);
1888 }
1889
1890 /*
1891 * Set @nr_bits bits in @bitmap starting from @bit.
1892 * Return the number of bits changed from 0 to 1.
1893 */
1894 static unsigned int dmz_set_bits(unsigned long *bitmap,
1895 unsigned int bit, unsigned int nr_bits)
1896 {
1897 unsigned long *addr;
1898 unsigned int end = bit + nr_bits;
1899 unsigned int n = 0;
1900
1901 while (bit < end) {
1902 if (((bit & (BITS_PER_LONG - 1)) == 0) &&
1903 ((end - bit) >= BITS_PER_LONG)) {
1904 /* Try to set the whole word at once */
1905 addr = bitmap + BIT_WORD(bit);
1906 if (*addr == 0) {
1907 *addr = ULONG_MAX;
1908 n += BITS_PER_LONG;
1909 bit += BITS_PER_LONG;
1910 continue;
1911 }
1912 }
1913
1914 if (!test_and_set_bit(bit, bitmap))
1915 n++;
1916 bit++;
1917 }
1918
1919 return n;
1920 }
1921
1922 /*
1923 * Get the bitmap block storing the bit for chunk_block in zone.
1924 */
1925 static struct dmz_mblock *dmz_get_bitmap(struct dmz_metadata *zmd,
1926 struct dm_zone *zone,
1927 sector_t chunk_block)
1928 {
1929 sector_t bitmap_block = 1 + zmd->nr_map_blocks +
1930 (sector_t)(dmz_id(zmd, zone) * zmd->zone_nr_bitmap_blocks) +
1931 (chunk_block >> DMZ_BLOCK_SHIFT_BITS);
1932
1933 return dmz_get_mblock(zmd, bitmap_block);
1934 }
1935
1936 /*
1937 * Copy the valid blocks bitmap of from_zone to the bitmap of to_zone.
1938 */
1939 int dmz_copy_valid_blocks(struct dmz_metadata *zmd, struct dm_zone *from_zone,
1940 struct dm_zone *to_zone)
1941 {
1942 struct dmz_mblock *from_mblk, *to_mblk;
1943 sector_t chunk_block = 0;
1944
1945 /* Get the zones bitmap blocks */
1946 while (chunk_block < zmd->dev->zone_nr_blocks) {
1947 from_mblk = dmz_get_bitmap(zmd, from_zone, chunk_block);
1948 if (IS_ERR(from_mblk))
1949 return PTR_ERR(from_mblk);
1950 to_mblk = dmz_get_bitmap(zmd, to_zone, chunk_block);
1951 if (IS_ERR(to_mblk)) {
1952 dmz_release_mblock(zmd, from_mblk);
1953 return PTR_ERR(to_mblk);
1954 }
1955
1956 memcpy(to_mblk->data, from_mblk->data, DMZ_BLOCK_SIZE);
1957 dmz_dirty_mblock(zmd, to_mblk);
1958
1959 dmz_release_mblock(zmd, to_mblk);
1960 dmz_release_mblock(zmd, from_mblk);
1961
1962 chunk_block += zmd->zone_bits_per_mblk;
1963 }
1964
1965 to_zone->weight = from_zone->weight;
1966
1967 return 0;
1968 }
1969
1970 /*
1971 * Merge the valid blocks bitmap of from_zone into the bitmap of to_zone,
1972 * starting from chunk_block.
1973 */
1974 int dmz_merge_valid_blocks(struct dmz_metadata *zmd, struct dm_zone *from_zone,
1975 struct dm_zone *to_zone, sector_t chunk_block)
1976 {
1977 unsigned int nr_blocks;
1978 int ret;
1979
1980 /* Get the zones bitmap blocks */
1981 while (chunk_block < zmd->dev->zone_nr_blocks) {
1982 /* Get a valid region from the source zone */
1983 ret = dmz_first_valid_block(zmd, from_zone, &chunk_block);
1984 if (ret <= 0)
1985 return ret;
1986
1987 nr_blocks = ret;
1988 ret = dmz_validate_blocks(zmd, to_zone, chunk_block, nr_blocks);
1989 if (ret)
1990 return ret;
1991
1992 chunk_block += nr_blocks;
1993 }
1994
1995 return 0;
1996 }
1997
1998 /*
1999 * Validate all the blocks in the range [block..block+nr_blocks-1].
2000 */
2001 int dmz_validate_blocks(struct dmz_metadata *zmd, struct dm_zone *zone,
2002 sector_t chunk_block, unsigned int nr_blocks)
2003 {
2004 unsigned int count, bit, nr_bits;
2005 unsigned int zone_nr_blocks = zmd->dev->zone_nr_blocks;
2006 struct dmz_mblock *mblk;
2007 unsigned int n = 0;
2008
2009 dmz_dev_debug(zmd->dev, "=> VALIDATE zone %u, block %llu, %u blocks",
2010 dmz_id(zmd, zone), (unsigned long long)chunk_block,
2011 nr_blocks);
2012
2013 WARN_ON(chunk_block + nr_blocks > zone_nr_blocks);
2014
2015 while (nr_blocks) {
2016 /* Get bitmap block */
2017 mblk = dmz_get_bitmap(zmd, zone, chunk_block);
2018 if (IS_ERR(mblk))
2019 return PTR_ERR(mblk);
2020
2021 /* Set bits */
2022 bit = chunk_block & DMZ_BLOCK_MASK_BITS;
2023 nr_bits = min(nr_blocks, zmd->zone_bits_per_mblk - bit);
2024
2025 count = dmz_set_bits((unsigned long *)mblk->data, bit, nr_bits);
2026 if (count) {
2027 dmz_dirty_mblock(zmd, mblk);
2028 n += count;
2029 }
2030 dmz_release_mblock(zmd, mblk);
2031
2032 nr_blocks -= nr_bits;
2033 chunk_block += nr_bits;
2034 }
2035
2036 if (likely(zone->weight + n <= zone_nr_blocks))
2037 zone->weight += n;
2038 else {
2039 dmz_dev_warn(zmd->dev, "Zone %u: weight %u should be <= %u",
2040 dmz_id(zmd, zone), zone->weight,
2041 zone_nr_blocks - n);
2042 zone->weight = zone_nr_blocks;
2043 }
2044
2045 return 0;
2046 }
2047
2048 /*
2049 * Clear nr_bits bits in bitmap starting from bit.
2050 * Return the number of bits cleared.
2051 */
2052 static int dmz_clear_bits(unsigned long *bitmap, int bit, int nr_bits)
2053 {
2054 unsigned long *addr;
2055 int end = bit + nr_bits;
2056 int n = 0;
2057
2058 while (bit < end) {
2059 if (((bit & (BITS_PER_LONG - 1)) == 0) &&
2060 ((end - bit) >= BITS_PER_LONG)) {
2061 /* Try to clear whole word at once */
2062 addr = bitmap + BIT_WORD(bit);
2063 if (*addr == ULONG_MAX) {
2064 *addr = 0;
2065 n += BITS_PER_LONG;
2066 bit += BITS_PER_LONG;
2067 continue;
2068 }
2069 }
2070
2071 if (test_and_clear_bit(bit, bitmap))
2072 n++;
2073 bit++;
2074 }
2075
2076 return n;
2077 }
2078
2079 /*
2080 * Invalidate all the blocks in the range [block..block+nr_blocks-1].
2081 */
2082 int dmz_invalidate_blocks(struct dmz_metadata *zmd, struct dm_zone *zone,
2083 sector_t chunk_block, unsigned int nr_blocks)
2084 {
2085 unsigned int count, bit, nr_bits;
2086 struct dmz_mblock *mblk;
2087 unsigned int n = 0;
2088
2089 dmz_dev_debug(zmd->dev, "=> INVALIDATE zone %u, block %llu, %u blocks",
2090 dmz_id(zmd, zone), (u64)chunk_block, nr_blocks);
2091
2092 WARN_ON(chunk_block + nr_blocks > zmd->dev->zone_nr_blocks);
2093
2094 while (nr_blocks) {
2095 /* Get bitmap block */
2096 mblk = dmz_get_bitmap(zmd, zone, chunk_block);
2097 if (IS_ERR(mblk))
2098 return PTR_ERR(mblk);
2099
2100 /* Clear bits */
2101 bit = chunk_block & DMZ_BLOCK_MASK_BITS;
2102 nr_bits = min(nr_blocks, zmd->zone_bits_per_mblk - bit);
2103
2104 count = dmz_clear_bits((unsigned long *)mblk->data,
2105 bit, nr_bits);
2106 if (count) {
2107 dmz_dirty_mblock(zmd, mblk);
2108 n += count;
2109 }
2110 dmz_release_mblock(zmd, mblk);
2111
2112 nr_blocks -= nr_bits;
2113 chunk_block += nr_bits;
2114 }
2115
2116 if (zone->weight >= n)
2117 zone->weight -= n;
2118 else {
2119 dmz_dev_warn(zmd->dev, "Zone %u: weight %u should be >= %u",
2120 dmz_id(zmd, zone), zone->weight, n);
2121 zone->weight = 0;
2122 }
2123
2124 return 0;
2125 }
2126
2127 /*
2128 * Get a block bit value.
2129 */
2130 static int dmz_test_block(struct dmz_metadata *zmd, struct dm_zone *zone,
2131 sector_t chunk_block)
2132 {
2133 struct dmz_mblock *mblk;
2134 int ret;
2135
2136 WARN_ON(chunk_block >= zmd->dev->zone_nr_blocks);
2137
2138 /* Get bitmap block */
2139 mblk = dmz_get_bitmap(zmd, zone, chunk_block);
2140 if (IS_ERR(mblk))
2141 return PTR_ERR(mblk);
2142
2143 /* Get offset */
2144 ret = test_bit(chunk_block & DMZ_BLOCK_MASK_BITS,
2145 (unsigned long *) mblk->data) != 0;
2146
2147 dmz_release_mblock(zmd, mblk);
2148
2149 return ret;
2150 }
2151
2152 /*
2153 * Return the number of blocks from chunk_block to the first block with a bit
2154 * value specified by set. Search at most nr_blocks blocks from chunk_block.
2155 */
2156 static int dmz_to_next_set_block(struct dmz_metadata *zmd, struct dm_zone *zone,
2157 sector_t chunk_block, unsigned int nr_blocks,
2158 int set)
2159 {
2160 struct dmz_mblock *mblk;
2161 unsigned int bit, set_bit, nr_bits;
2162 unsigned int zone_bits = zmd->zone_bits_per_mblk;
2163 unsigned long *bitmap;
2164 int n = 0;
2165
2166 WARN_ON(chunk_block + nr_blocks > zmd->dev->zone_nr_blocks);
2167
2168 while (nr_blocks) {
2169 /* Get bitmap block */
2170 mblk = dmz_get_bitmap(zmd, zone, chunk_block);
2171 if (IS_ERR(mblk))
2172 return PTR_ERR(mblk);
2173
2174 /* Get offset */
2175 bitmap = (unsigned long *) mblk->data;
2176 bit = chunk_block & DMZ_BLOCK_MASK_BITS;
2177 nr_bits = min(nr_blocks, zone_bits - bit);
2178 if (set)
2179 set_bit = find_next_bit(bitmap, zone_bits, bit);
2180 else
2181 set_bit = find_next_zero_bit(bitmap, zone_bits, bit);
2182 dmz_release_mblock(zmd, mblk);
2183
2184 n += set_bit - bit;
2185 if (set_bit < zone_bits)
2186 break;
2187
2188 nr_blocks -= nr_bits;
2189 chunk_block += nr_bits;
2190 }
2191
2192 return n;
2193 }
2194
2195 /*
2196 * Test if chunk_block is valid. If it is, the number of consecutive
2197 * valid blocks from chunk_block will be returned.
2198 */
2199 int dmz_block_valid(struct dmz_metadata *zmd, struct dm_zone *zone,
2200 sector_t chunk_block)
2201 {
2202 int valid;
2203
2204 valid = dmz_test_block(zmd, zone, chunk_block);
2205 if (valid <= 0)
2206 return valid;
2207
2208 /* The block is valid: get the number of valid blocks from block */
2209 return dmz_to_next_set_block(zmd, zone, chunk_block,
2210 zmd->dev->zone_nr_blocks - chunk_block, 0);
2211 }
2212
2213 /*
2214 * Find the first valid block from @chunk_block in @zone.
2215 * If such a block is found, its number is returned using
2216 * @chunk_block and the total number of valid blocks from @chunk_block
2217 * is returned.
2218 */
2219 int dmz_first_valid_block(struct dmz_metadata *zmd, struct dm_zone *zone,
2220 sector_t *chunk_block)
2221 {
2222 sector_t start_block = *chunk_block;
2223 int ret;
2224
2225 ret = dmz_to_next_set_block(zmd, zone, start_block,
2226 zmd->dev->zone_nr_blocks - start_block, 1);
2227 if (ret < 0)
2228 return ret;
2229
2230 start_block += ret;
2231 *chunk_block = start_block;
2232
2233 return dmz_to_next_set_block(zmd, zone, start_block,
2234 zmd->dev->zone_nr_blocks - start_block, 0);
2235 }
2236
2237 /*
2238 * Count the number of bits set starting from bit up to bit + nr_bits - 1.
2239 */
2240 static int dmz_count_bits(void *bitmap, int bit, int nr_bits)
2241 {
2242 unsigned long *addr;
2243 int end = bit + nr_bits;
2244 int n = 0;
2245
2246 while (bit < end) {
2247 if (((bit & (BITS_PER_LONG - 1)) == 0) &&
2248 ((end - bit) >= BITS_PER_LONG)) {
2249 addr = (unsigned long *)bitmap + BIT_WORD(bit);
2250 if (*addr == ULONG_MAX) {
2251 n += BITS_PER_LONG;
2252 bit += BITS_PER_LONG;
2253 continue;
2254 }
2255 }
2256
2257 if (test_bit(bit, bitmap))
2258 n++;
2259 bit++;
2260 }
2261
2262 return n;
2263 }
2264
2265 /*
2266 * Get a zone weight.
2267 */
2268 static void dmz_get_zone_weight(struct dmz_metadata *zmd, struct dm_zone *zone)
2269 {
2270 struct dmz_mblock *mblk;
2271 sector_t chunk_block = 0;
2272 unsigned int bit, nr_bits;
2273 unsigned int nr_blocks = zmd->dev->zone_nr_blocks;
2274 void *bitmap;
2275 int n = 0;
2276
2277 while (nr_blocks) {
2278 /* Get bitmap block */
2279 mblk = dmz_get_bitmap(zmd, zone, chunk_block);
2280 if (IS_ERR(mblk)) {
2281 n = 0;
2282 break;
2283 }
2284
2285 /* Count bits in this block */
2286 bitmap = mblk->data;
2287 bit = chunk_block & DMZ_BLOCK_MASK_BITS;
2288 nr_bits = min(nr_blocks, zmd->zone_bits_per_mblk - bit);
2289 n += dmz_count_bits(bitmap, bit, nr_bits);
2290
2291 dmz_release_mblock(zmd, mblk);
2292
2293 nr_blocks -= nr_bits;
2294 chunk_block += nr_bits;
2295 }
2296
2297 zone->weight = n;
2298 }
2299
2300 /*
2301 * Cleanup the zoned metadata resources.
2302 */
2303 static void dmz_cleanup_metadata(struct dmz_metadata *zmd)
2304 {
2305 struct rb_root *root;
2306 struct dmz_mblock *mblk, *next;
2307 int i;
2308
2309 /* Release zone mapping resources */
2310 if (zmd->map_mblk) {
2311 for (i = 0; i < zmd->nr_map_blocks; i++)
2312 dmz_release_mblock(zmd, zmd->map_mblk[i]);
2313 kfree(zmd->map_mblk);
2314 zmd->map_mblk = NULL;
2315 }
2316
2317 /* Release super blocks */
2318 for (i = 0; i < 2; i++) {
2319 if (zmd->sb[i].mblk) {
2320 dmz_free_mblock(zmd, zmd->sb[i].mblk);
2321 zmd->sb[i].mblk = NULL;
2322 }
2323 }
2324
2325 /* Free cached blocks */
2326 while (!list_empty(&zmd->mblk_dirty_list)) {
2327 mblk = list_first_entry(&zmd->mblk_dirty_list,
2328 struct dmz_mblock, link);
2329 dmz_dev_warn(zmd->dev, "mblock %llu still in dirty list (ref %u)",
2330 (u64)mblk->no, mblk->ref);
2331 list_del_init(&mblk->link);
2332 rb_erase(&mblk->node, &zmd->mblk_rbtree);
2333 dmz_free_mblock(zmd, mblk);
2334 }
2335
2336 while (!list_empty(&zmd->mblk_lru_list)) {
2337 mblk = list_first_entry(&zmd->mblk_lru_list,
2338 struct dmz_mblock, link);
2339 list_del_init(&mblk->link);
2340 rb_erase(&mblk->node, &zmd->mblk_rbtree);
2341 dmz_free_mblock(zmd, mblk);
2342 }
2343
2344 /* Sanity checks: the mblock rbtree should now be empty */
2345 root = &zmd->mblk_rbtree;
2346 rbtree_postorder_for_each_entry_safe(mblk, next, root, node) {
2347 dmz_dev_warn(zmd->dev, "mblock %llu ref %u still in rbtree",
2348 (u64)mblk->no, mblk->ref);
2349 mblk->ref = 0;
2350 dmz_free_mblock(zmd, mblk);
2351 }
2352
2353 /* Free the zone descriptors */
2354 dmz_drop_zones(zmd);
2355
2356 mutex_destroy(&zmd->mblk_flush_lock);
2357 mutex_destroy(&zmd->map_lock);
2358 }
2359
2360 /*
2361 * Initialize the zoned metadata.
2362 */
2363 int dmz_ctr_metadata(struct dmz_dev *dev, struct dmz_metadata **metadata)
2364 {
2365 struct dmz_metadata *zmd;
2366 unsigned int i, zid;
2367 struct dm_zone *zone;
2368 int ret;
2369
2370 zmd = kzalloc(sizeof(struct dmz_metadata), GFP_KERNEL);
2371 if (!zmd)
2372 return -ENOMEM;
2373
2374 zmd->dev = dev;
2375 zmd->mblk_rbtree = RB_ROOT;
2376 init_rwsem(&zmd->mblk_sem);
2377 mutex_init(&zmd->mblk_flush_lock);
2378 spin_lock_init(&zmd->mblk_lock);
2379 INIT_LIST_HEAD(&zmd->mblk_lru_list);
2380 INIT_LIST_HEAD(&zmd->mblk_dirty_list);
2381
2382 mutex_init(&zmd->map_lock);
2383 atomic_set(&zmd->unmap_nr_rnd, 0);
2384 INIT_LIST_HEAD(&zmd->unmap_rnd_list);
2385 INIT_LIST_HEAD(&zmd->map_rnd_list);
2386
2387 atomic_set(&zmd->unmap_nr_seq, 0);
2388 INIT_LIST_HEAD(&zmd->unmap_seq_list);
2389 INIT_LIST_HEAD(&zmd->map_seq_list);
2390
2391 atomic_set(&zmd->nr_reserved_seq_zones, 0);
2392 INIT_LIST_HEAD(&zmd->reserved_seq_zones_list);
2393
2394 init_waitqueue_head(&zmd->free_wq);
2395
2396 /* Initialize zone descriptors */
2397 ret = dmz_init_zones(zmd);
2398 if (ret)
2399 goto err;
2400
2401 /* Get super block */
2402 ret = dmz_load_sb(zmd);
2403 if (ret)
2404 goto err;
2405
2406 /* Set metadata zones starting from sb_zone */
2407 zid = dmz_id(zmd, zmd->sb_zone);
2408 for (i = 0; i < zmd->nr_meta_zones << 1; i++) {
2409 zone = dmz_get(zmd, zid + i);
2410 if (!dmz_is_rnd(zone))
2411 goto err;
2412 set_bit(DMZ_META, &zone->flags);
2413 }
2414
2415 /* Load mapping table */
2416 ret = dmz_load_mapping(zmd);
2417 if (ret)
2418 goto err;
2419
2420 /*
2421 * Cache size boundaries: allow at least 2 super blocks, the chunk map
2422 * blocks and enough blocks to be able to cache the bitmap blocks of
2423 * up to 16 zones when idle (min_nr_mblks). Otherwise, if busy, allow
2424 * the cache to add 512 more metadata blocks.
2425 */
2426 zmd->min_nr_mblks = 2 + zmd->nr_map_blocks + zmd->zone_nr_bitmap_blocks * 16;
2427 zmd->max_nr_mblks = zmd->min_nr_mblks + 512;
2428 zmd->mblk_shrinker.count_objects = dmz_mblock_shrinker_count;
2429 zmd->mblk_shrinker.scan_objects = dmz_mblock_shrinker_scan;
2430 zmd->mblk_shrinker.seeks = DEFAULT_SEEKS;
2431
2432 /* Metadata cache shrinker */
2433 ret = register_shrinker(&zmd->mblk_shrinker);
2434 if (ret) {
2435 dmz_dev_err(dev, "Register metadata cache shrinker failed");
2436 goto err;
2437 }
2438
2439 dmz_dev_info(dev, "Host-%s zoned block device",
2440 bdev_zoned_model(dev->bdev) == BLK_ZONED_HA ?
2441 "aware" : "managed");
2442 dmz_dev_info(dev, " %llu 512-byte logical sectors",
2443 (u64)dev->capacity);
2444 dmz_dev_info(dev, " %u zones of %llu 512-byte logical sectors",
2445 dev->nr_zones, (u64)dev->zone_nr_sectors);
2446 dmz_dev_info(dev, " %u metadata zones",
2447 zmd->nr_meta_zones * 2);
2448 dmz_dev_info(dev, " %u data zones for %u chunks",
2449 zmd->nr_data_zones, zmd->nr_chunks);
2450 dmz_dev_info(dev, " %u random zones (%u unmapped)",
2451 zmd->nr_rnd, atomic_read(&zmd->unmap_nr_rnd));
2452 dmz_dev_info(dev, " %u sequential zones (%u unmapped)",
2453 zmd->nr_seq, atomic_read(&zmd->unmap_nr_seq));
2454 dmz_dev_info(dev, " %u reserved sequential data zones",
2455 zmd->nr_reserved_seq);
2456
2457 dmz_dev_debug(dev, "Format:");
2458 dmz_dev_debug(dev, "%u metadata blocks per set (%u max cache)",
2459 zmd->nr_meta_blocks, zmd->max_nr_mblks);
2460 dmz_dev_debug(dev, " %u data zone mapping blocks",
2461 zmd->nr_map_blocks);
2462 dmz_dev_debug(dev, " %u bitmap blocks",
2463 zmd->nr_bitmap_blocks);
2464
2465 *metadata = zmd;
2466
2467 return 0;
2468 err:
2469 dmz_cleanup_metadata(zmd);
2470 kfree(zmd);
2471 *metadata = NULL;
2472
2473 return ret;
2474 }
2475
2476 /*
2477 * Cleanup the zoned metadata resources.
2478 */
2479 void dmz_dtr_metadata(struct dmz_metadata *zmd)
2480 {
2481 unregister_shrinker(&zmd->mblk_shrinker);
2482 dmz_cleanup_metadata(zmd);
2483 kfree(zmd);
2484 }
2485
2486 /*
2487 * Check zone information on resume.
2488 */
2489 int dmz_resume_metadata(struct dmz_metadata *zmd)
2490 {
2491 struct dmz_dev *dev = zmd->dev;
2492 struct dm_zone *zone;
2493 sector_t wp_block;
2494 unsigned int i;
2495 int ret;
2496
2497 /* Check zones */
2498 for (i = 0; i < dev->nr_zones; i++) {
2499 zone = dmz_get(zmd, i);
2500 if (!zone) {
2501 dmz_dev_err(dev, "Unable to get zone %u", i);
2502 return -EIO;
2503 }
2504
2505 wp_block = zone->wp_block;
2506
2507 ret = dmz_update_zone(zmd, zone);
2508 if (ret) {
2509 dmz_dev_err(dev, "Broken zone %u", i);
2510 return ret;
2511 }
2512
2513 if (dmz_is_offline(zone)) {
2514 dmz_dev_warn(dev, "Zone %u is offline", i);
2515 continue;
2516 }
2517
2518 /* Check write pointer */
2519 if (!dmz_is_seq(zone))
2520 zone->wp_block = 0;
2521 else if (zone->wp_block != wp_block) {
2522 dmz_dev_err(dev, "Zone %u: Invalid wp (%llu / %llu)",
2523 i, (u64)zone->wp_block, (u64)wp_block);
2524 zone->wp_block = wp_block;
2525 dmz_invalidate_blocks(zmd, zone, zone->wp_block,
2526 dev->zone_nr_blocks - zone->wp_block);
2527 }
2528 }
2529
2530 return 0;
2531 }
Linux with added FPC-III support