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1// SPDX-License-Identifier: GPL-2.0
2#include <linux/vmalloc.h>
3#include <linux/bitmap.h>
4#include "null_blk.h"
5
6#define CREATE_TRACE_POINTS
7#include "trace.h"
8
9#undef pr_fmt
10#define pr_fmt(fmt) "null_blk: " fmt
11
12static inline sector_t mb_to_sects(unsigned long mb)
13{
14 return ((sector_t)mb * SZ_1M) >> SECTOR_SHIFT;
15}
16
17static inline unsigned int null_zone_no(struct nullb_device *dev, sector_t sect)
18{
19 return sect >> ilog2(dev->zone_size_sects);
20}
21
22static inline void null_lock_zone_res(struct nullb_device *dev)
23{
24 if (dev->need_zone_res_mgmt)
25 spin_lock_irq(&dev->zone_res_lock);
26}
27
28static inline void null_unlock_zone_res(struct nullb_device *dev)
29{
30 if (dev->need_zone_res_mgmt)
31 spin_unlock_irq(&dev->zone_res_lock);
32}
33
34static inline void null_init_zone_lock(struct nullb_device *dev,
35 struct nullb_zone *zone)
36{
37 if (!dev->memory_backed)
38 spin_lock_init(&zone->spinlock);
39 else
40 mutex_init(&zone->mutex);
41}
42
43static inline void null_lock_zone(struct nullb_device *dev,
44 struct nullb_zone *zone)
45{
46 if (!dev->memory_backed)
47 spin_lock_irq(&zone->spinlock);
48 else
49 mutex_lock(&zone->mutex);
50}
51
52static inline void null_unlock_zone(struct nullb_device *dev,
53 struct nullb_zone *zone)
54{
55 if (!dev->memory_backed)
56 spin_unlock_irq(&zone->spinlock);
57 else
58 mutex_unlock(&zone->mutex);
59}
60
61int null_init_zoned_dev(struct nullb_device *dev, struct request_queue *q)
62{
63 sector_t dev_capacity_sects, zone_capacity_sects;
64 struct nullb_zone *zone;
65 sector_t sector = 0;
66 unsigned int i;
67
68 if (!is_power_of_2(dev->zone_size)) {
69 pr_err("zone_size must be power-of-two\n");
70 return -EINVAL;
71 }
72 if (dev->zone_size > dev->size) {
73 pr_err("Zone size larger than device capacity\n");
74 return -EINVAL;
75 }
76
77 if (!dev->zone_capacity)
78 dev->zone_capacity = dev->zone_size;
79
80 if (dev->zone_capacity > dev->zone_size) {
81 pr_err("zone capacity (%lu MB) larger than zone size (%lu MB)\n",
82 dev->zone_capacity, dev->zone_size);
83 return -EINVAL;
84 }
85
86 zone_capacity_sects = mb_to_sects(dev->zone_capacity);
87 dev_capacity_sects = mb_to_sects(dev->size);
88 dev->zone_size_sects = mb_to_sects(dev->zone_size);
89 dev->nr_zones = round_up(dev_capacity_sects, dev->zone_size_sects)
90 >> ilog2(dev->zone_size_sects);
91
92 dev->zones = kvmalloc_array(dev->nr_zones, sizeof(struct nullb_zone),
93 GFP_KERNEL | __GFP_ZERO);
94 if (!dev->zones)
95 return -ENOMEM;
96
97 spin_lock_init(&dev->zone_res_lock);
98
99 if (dev->zone_nr_conv >= dev->nr_zones) {
100 dev->zone_nr_conv = dev->nr_zones - 1;
101 pr_info("changed the number of conventional zones to %u",
102 dev->zone_nr_conv);
103 }
104
105 /* Max active zones has to be < nbr of seq zones in order to be enforceable */
106 if (dev->zone_max_active >= dev->nr_zones - dev->zone_nr_conv) {
107 dev->zone_max_active = 0;
108 pr_info("zone_max_active limit disabled, limit >= zone count\n");
109 }
110
111 /* Max open zones has to be <= max active zones */
112 if (dev->zone_max_active && dev->zone_max_open > dev->zone_max_active) {
113 dev->zone_max_open = dev->zone_max_active;
114 pr_info("changed the maximum number of open zones to %u\n",
115 dev->nr_zones);
116 } else if (dev->zone_max_open >= dev->nr_zones - dev->zone_nr_conv) {
117 dev->zone_max_open = 0;
118 pr_info("zone_max_open limit disabled, limit >= zone count\n");
119 }
120 dev->need_zone_res_mgmt = dev->zone_max_active || dev->zone_max_open;
121 dev->imp_close_zone_no = dev->zone_nr_conv;
122
123 for (i = 0; i < dev->zone_nr_conv; i++) {
124 zone = &dev->zones[i];
125
126 null_init_zone_lock(dev, zone);
127 zone->start = sector;
128 zone->len = dev->zone_size_sects;
129 zone->capacity = zone->len;
130 zone->wp = zone->start + zone->len;
131 zone->type = BLK_ZONE_TYPE_CONVENTIONAL;
132 zone->cond = BLK_ZONE_COND_NOT_WP;
133
134 sector += dev->zone_size_sects;
135 }
136
137 for (i = dev->zone_nr_conv; i < dev->nr_zones; i++) {
138 zone = &dev->zones[i];
139
140 null_init_zone_lock(dev, zone);
141 zone->start = zone->wp = sector;
142 if (zone->start + dev->zone_size_sects > dev_capacity_sects)
143 zone->len = dev_capacity_sects - zone->start;
144 else
145 zone->len = dev->zone_size_sects;
146 zone->capacity =
147 min_t(sector_t, zone->len, zone_capacity_sects);
148 zone->type = BLK_ZONE_TYPE_SEQWRITE_REQ;
149 zone->cond = BLK_ZONE_COND_EMPTY;
150
151 sector += dev->zone_size_sects;
152 }
153
154 return 0;
155}
156
157int null_register_zoned_dev(struct nullb *nullb)
158{
159 struct nullb_device *dev = nullb->dev;
160 struct request_queue *q = nullb->q;
161
162 disk_set_zoned(nullb->disk);
163 blk_queue_flag_set(QUEUE_FLAG_ZONE_RESETALL, q);
164 blk_queue_required_elevator_features(q, ELEVATOR_F_ZBD_SEQ_WRITE);
165 blk_queue_chunk_sectors(q, dev->zone_size_sects);
166 nullb->disk->nr_zones = bdev_nr_zones(nullb->disk->part0);
167 blk_queue_max_zone_append_sectors(q, dev->zone_size_sects);
168 disk_set_max_open_zones(nullb->disk, dev->zone_max_open);
169 disk_set_max_active_zones(nullb->disk, dev->zone_max_active);
170
171 if (queue_is_mq(q))
172 return blk_revalidate_disk_zones(nullb->disk, NULL);
173
174 return 0;
175}
176
177void null_free_zoned_dev(struct nullb_device *dev)
178{
179 kvfree(dev->zones);
180 dev->zones = NULL;
181}
182
183int null_report_zones(struct gendisk *disk, sector_t sector,
184 unsigned int nr_zones, report_zones_cb cb, void *data)
185{
186 struct nullb *nullb = disk->private_data;
187 struct nullb_device *dev = nullb->dev;
188 unsigned int first_zone, i;
189 struct nullb_zone *zone;
190 struct blk_zone blkz;
191 int error;
192
193 first_zone = null_zone_no(dev, sector);
194 if (first_zone >= dev->nr_zones)
195 return 0;
196
197 nr_zones = min(nr_zones, dev->nr_zones - first_zone);
198 trace_nullb_report_zones(nullb, nr_zones);
199
200 memset(&blkz, 0, sizeof(struct blk_zone));
201 zone = &dev->zones[first_zone];
202 for (i = 0; i < nr_zones; i++, zone++) {
203 /*
204 * Stacked DM target drivers will remap the zone information by
205 * modifying the zone information passed to the report callback.
206 * So use a local copy to avoid corruption of the device zone
207 * array.
208 */
209 null_lock_zone(dev, zone);
210 blkz.start = zone->start;
211 blkz.len = zone->len;
212 blkz.wp = zone->wp;
213 blkz.type = zone->type;
214 blkz.cond = zone->cond;
215 blkz.capacity = zone->capacity;
216 null_unlock_zone(dev, zone);
217
218 error = cb(&blkz, i, data);
219 if (error)
220 return error;
221 }
222
223 return nr_zones;
224}
225
226/*
227 * This is called in the case of memory backing from null_process_cmd()
228 * with the target zone already locked.
229 */
230size_t null_zone_valid_read_len(struct nullb *nullb,
231 sector_t sector, unsigned int len)
232{
233 struct nullb_device *dev = nullb->dev;
234 struct nullb_zone *zone = &dev->zones[null_zone_no(dev, sector)];
235 unsigned int nr_sectors = len >> SECTOR_SHIFT;
236
237 /* Read must be below the write pointer position */
238 if (zone->type == BLK_ZONE_TYPE_CONVENTIONAL ||
239 sector + nr_sectors <= zone->wp)
240 return len;
241
242 if (sector > zone->wp)
243 return 0;
244
245 return (zone->wp - sector) << SECTOR_SHIFT;
246}
247
248static blk_status_t __null_close_zone(struct nullb_device *dev,
249 struct nullb_zone *zone)
250{
251 switch (zone->cond) {
252 case BLK_ZONE_COND_CLOSED:
253 /* close operation on closed is not an error */
254 return BLK_STS_OK;
255 case BLK_ZONE_COND_IMP_OPEN:
256 dev->nr_zones_imp_open--;
257 break;
258 case BLK_ZONE_COND_EXP_OPEN:
259 dev->nr_zones_exp_open--;
260 break;
261 case BLK_ZONE_COND_EMPTY:
262 case BLK_ZONE_COND_FULL:
263 default:
264 return BLK_STS_IOERR;
265 }
266
267 if (zone->wp == zone->start) {
268 zone->cond = BLK_ZONE_COND_EMPTY;
269 } else {
270 zone->cond = BLK_ZONE_COND_CLOSED;
271 dev->nr_zones_closed++;
272 }
273
274 return BLK_STS_OK;
275}
276
277static void null_close_imp_open_zone(struct nullb_device *dev)
278{
279 struct nullb_zone *zone;
280 unsigned int zno, i;
281
282 zno = dev->imp_close_zone_no;
283 if (zno >= dev->nr_zones)
284 zno = dev->zone_nr_conv;
285
286 for (i = dev->zone_nr_conv; i < dev->nr_zones; i++) {
287 zone = &dev->zones[zno];
288 zno++;
289 if (zno >= dev->nr_zones)
290 zno = dev->zone_nr_conv;
291
292 if (zone->cond == BLK_ZONE_COND_IMP_OPEN) {
293 __null_close_zone(dev, zone);
294 dev->imp_close_zone_no = zno;
295 return;
296 }
297 }
298}
299
300static blk_status_t null_check_active(struct nullb_device *dev)
301{
302 if (!dev->zone_max_active)
303 return BLK_STS_OK;
304
305 if (dev->nr_zones_exp_open + dev->nr_zones_imp_open +
306 dev->nr_zones_closed < dev->zone_max_active)
307 return BLK_STS_OK;
308
309 return BLK_STS_ZONE_ACTIVE_RESOURCE;
310}
311
312static blk_status_t null_check_open(struct nullb_device *dev)
313{
314 if (!dev->zone_max_open)
315 return BLK_STS_OK;
316
317 if (dev->nr_zones_exp_open + dev->nr_zones_imp_open < dev->zone_max_open)
318 return BLK_STS_OK;
319
320 if (dev->nr_zones_imp_open) {
321 if (null_check_active(dev) == BLK_STS_OK) {
322 null_close_imp_open_zone(dev);
323 return BLK_STS_OK;
324 }
325 }
326
327 return BLK_STS_ZONE_OPEN_RESOURCE;
328}
329
330/*
331 * This function matches the manage open zone resources function in the ZBC standard,
332 * with the addition of max active zones support (added in the ZNS standard).
333 *
334 * The function determines if a zone can transition to implicit open or explicit open,
335 * while maintaining the max open zone (and max active zone) limit(s). It may close an
336 * implicit open zone in order to make additional zone resources available.
337 *
338 * ZBC states that an implicit open zone shall be closed only if there is not
339 * room within the open limit. However, with the addition of an active limit,
340 * it is not certain that closing an implicit open zone will allow a new zone
341 * to be opened, since we might already be at the active limit capacity.
342 */
343static blk_status_t null_check_zone_resources(struct nullb_device *dev,
344 struct nullb_zone *zone)
345{
346 blk_status_t ret;
347
348 switch (zone->cond) {
349 case BLK_ZONE_COND_EMPTY:
350 ret = null_check_active(dev);
351 if (ret != BLK_STS_OK)
352 return ret;
353 fallthrough;
354 case BLK_ZONE_COND_CLOSED:
355 return null_check_open(dev);
356 default:
357 /* Should never be called for other states */
358 WARN_ON(1);
359 return BLK_STS_IOERR;
360 }
361}
362
363static blk_status_t null_zone_write(struct nullb_cmd *cmd, sector_t sector,
364 unsigned int nr_sectors, bool append)
365{
366 struct nullb_device *dev = cmd->nq->dev;
367 unsigned int zno = null_zone_no(dev, sector);
368 struct nullb_zone *zone = &dev->zones[zno];
369 blk_status_t ret;
370
371 trace_nullb_zone_op(cmd, zno, zone->cond);
372
373 if (zone->type == BLK_ZONE_TYPE_CONVENTIONAL) {
374 if (append)
375 return BLK_STS_IOERR;
376 return null_process_cmd(cmd, REQ_OP_WRITE, sector, nr_sectors);
377 }
378
379 null_lock_zone(dev, zone);
380
381 if (zone->cond == BLK_ZONE_COND_FULL ||
382 zone->cond == BLK_ZONE_COND_READONLY ||
383 zone->cond == BLK_ZONE_COND_OFFLINE) {
384 /* Cannot write to the zone */
385 ret = BLK_STS_IOERR;
386 goto unlock;
387 }
388
389 /*
390 * Regular writes must be at the write pointer position.
391 * Zone append writes are automatically issued at the write
392 * pointer and the position returned using the request or BIO
393 * sector.
394 */
395 if (append) {
396 sector = zone->wp;
397 if (dev->queue_mode == NULL_Q_MQ)
398 cmd->rq->__sector = sector;
399 else
400 cmd->bio->bi_iter.bi_sector = sector;
401 } else if (sector != zone->wp) {
402 ret = BLK_STS_IOERR;
403 goto unlock;
404 }
405
406 if (zone->wp + nr_sectors > zone->start + zone->capacity) {
407 ret = BLK_STS_IOERR;
408 goto unlock;
409 }
410
411 if (zone->cond == BLK_ZONE_COND_CLOSED ||
412 zone->cond == BLK_ZONE_COND_EMPTY) {
413 null_lock_zone_res(dev);
414
415 ret = null_check_zone_resources(dev, zone);
416 if (ret != BLK_STS_OK) {
417 null_unlock_zone_res(dev);
418 goto unlock;
419 }
420 if (zone->cond == BLK_ZONE_COND_CLOSED) {
421 dev->nr_zones_closed--;
422 dev->nr_zones_imp_open++;
423 } else if (zone->cond == BLK_ZONE_COND_EMPTY) {
424 dev->nr_zones_imp_open++;
425 }
426
427 if (zone->cond != BLK_ZONE_COND_EXP_OPEN)
428 zone->cond = BLK_ZONE_COND_IMP_OPEN;
429
430 null_unlock_zone_res(dev);
431 }
432
433 ret = null_process_cmd(cmd, REQ_OP_WRITE, sector, nr_sectors);
434 if (ret != BLK_STS_OK)
435 goto unlock;
436
437 zone->wp += nr_sectors;
438 if (zone->wp == zone->start + zone->capacity) {
439 null_lock_zone_res(dev);
440 if (zone->cond == BLK_ZONE_COND_EXP_OPEN)
441 dev->nr_zones_exp_open--;
442 else if (zone->cond == BLK_ZONE_COND_IMP_OPEN)
443 dev->nr_zones_imp_open--;
444 zone->cond = BLK_ZONE_COND_FULL;
445 null_unlock_zone_res(dev);
446 }
447
448 ret = BLK_STS_OK;
449
450unlock:
451 null_unlock_zone(dev, zone);
452
453 return ret;
454}
455
456static blk_status_t null_open_zone(struct nullb_device *dev,
457 struct nullb_zone *zone)
458{
459 blk_status_t ret = BLK_STS_OK;
460
461 if (zone->type == BLK_ZONE_TYPE_CONVENTIONAL)
462 return BLK_STS_IOERR;
463
464 null_lock_zone_res(dev);
465
466 switch (zone->cond) {
467 case BLK_ZONE_COND_EXP_OPEN:
468 /* open operation on exp open is not an error */
469 goto unlock;
470 case BLK_ZONE_COND_EMPTY:
471 ret = null_check_zone_resources(dev, zone);
472 if (ret != BLK_STS_OK)
473 goto unlock;
474 break;
475 case BLK_ZONE_COND_IMP_OPEN:
476 dev->nr_zones_imp_open--;
477 break;
478 case BLK_ZONE_COND_CLOSED:
479 ret = null_check_zone_resources(dev, zone);
480 if (ret != BLK_STS_OK)
481 goto unlock;
482 dev->nr_zones_closed--;
483 break;
484 case BLK_ZONE_COND_FULL:
485 default:
486 ret = BLK_STS_IOERR;
487 goto unlock;
488 }
489
490 zone->cond = BLK_ZONE_COND_EXP_OPEN;
491 dev->nr_zones_exp_open++;
492
493unlock:
494 null_unlock_zone_res(dev);
495
496 return ret;
497}
498
499static blk_status_t null_close_zone(struct nullb_device *dev,
500 struct nullb_zone *zone)
501{
502 blk_status_t ret;
503
504 if (zone->type == BLK_ZONE_TYPE_CONVENTIONAL)
505 return BLK_STS_IOERR;
506
507 null_lock_zone_res(dev);
508 ret = __null_close_zone(dev, zone);
509 null_unlock_zone_res(dev);
510
511 return ret;
512}
513
514static blk_status_t null_finish_zone(struct nullb_device *dev,
515 struct nullb_zone *zone)
516{
517 blk_status_t ret = BLK_STS_OK;
518
519 if (zone->type == BLK_ZONE_TYPE_CONVENTIONAL)
520 return BLK_STS_IOERR;
521
522 null_lock_zone_res(dev);
523
524 switch (zone->cond) {
525 case BLK_ZONE_COND_FULL:
526 /* finish operation on full is not an error */
527 goto unlock;
528 case BLK_ZONE_COND_EMPTY:
529 ret = null_check_zone_resources(dev, zone);
530 if (ret != BLK_STS_OK)
531 goto unlock;
532 break;
533 case BLK_ZONE_COND_IMP_OPEN:
534 dev->nr_zones_imp_open--;
535 break;
536 case BLK_ZONE_COND_EXP_OPEN:
537 dev->nr_zones_exp_open--;
538 break;
539 case BLK_ZONE_COND_CLOSED:
540 ret = null_check_zone_resources(dev, zone);
541 if (ret != BLK_STS_OK)
542 goto unlock;
543 dev->nr_zones_closed--;
544 break;
545 default:
546 ret = BLK_STS_IOERR;
547 goto unlock;
548 }
549
550 zone->cond = BLK_ZONE_COND_FULL;
551 zone->wp = zone->start + zone->len;
552
553unlock:
554 null_unlock_zone_res(dev);
555
556 return ret;
557}
558
559static blk_status_t null_reset_zone(struct nullb_device *dev,
560 struct nullb_zone *zone)
561{
562 if (zone->type == BLK_ZONE_TYPE_CONVENTIONAL)
563 return BLK_STS_IOERR;
564
565 null_lock_zone_res(dev);
566
567 switch (zone->cond) {
568 case BLK_ZONE_COND_EMPTY:
569 /* reset operation on empty is not an error */
570 null_unlock_zone_res(dev);
571 return BLK_STS_OK;
572 case BLK_ZONE_COND_IMP_OPEN:
573 dev->nr_zones_imp_open--;
574 break;
575 case BLK_ZONE_COND_EXP_OPEN:
576 dev->nr_zones_exp_open--;
577 break;
578 case BLK_ZONE_COND_CLOSED:
579 dev->nr_zones_closed--;
580 break;
581 case BLK_ZONE_COND_FULL:
582 break;
583 default:
584 null_unlock_zone_res(dev);
585 return BLK_STS_IOERR;
586 }
587
588 zone->cond = BLK_ZONE_COND_EMPTY;
589 zone->wp = zone->start;
590
591 null_unlock_zone_res(dev);
592
593 if (dev->memory_backed)
594 return null_handle_discard(dev, zone->start, zone->len);
595
596 return BLK_STS_OK;
597}
598
599static blk_status_t null_zone_mgmt(struct nullb_cmd *cmd, enum req_op op,
600 sector_t sector)
601{
602 struct nullb_device *dev = cmd->nq->dev;
603 unsigned int zone_no;
604 struct nullb_zone *zone;
605 blk_status_t ret;
606 size_t i;
607
608 if (op == REQ_OP_ZONE_RESET_ALL) {
609 for (i = dev->zone_nr_conv; i < dev->nr_zones; i++) {
610 zone = &dev->zones[i];
611 null_lock_zone(dev, zone);
612 if (zone->cond != BLK_ZONE_COND_EMPTY &&
613 zone->cond != BLK_ZONE_COND_READONLY &&
614 zone->cond != BLK_ZONE_COND_OFFLINE) {
615 null_reset_zone(dev, zone);
616 trace_nullb_zone_op(cmd, i, zone->cond);
617 }
618 null_unlock_zone(dev, zone);
619 }
620 return BLK_STS_OK;
621 }
622
623 zone_no = null_zone_no(dev, sector);
624 zone = &dev->zones[zone_no];
625
626 null_lock_zone(dev, zone);
627
628 if (zone->cond == BLK_ZONE_COND_READONLY ||
629 zone->cond == BLK_ZONE_COND_OFFLINE) {
630 ret = BLK_STS_IOERR;
631 goto unlock;
632 }
633
634 switch (op) {
635 case REQ_OP_ZONE_RESET:
636 ret = null_reset_zone(dev, zone);
637 break;
638 case REQ_OP_ZONE_OPEN:
639 ret = null_open_zone(dev, zone);
640 break;
641 case REQ_OP_ZONE_CLOSE:
642 ret = null_close_zone(dev, zone);
643 break;
644 case REQ_OP_ZONE_FINISH:
645 ret = null_finish_zone(dev, zone);
646 break;
647 default:
648 ret = BLK_STS_NOTSUPP;
649 break;
650 }
651
652 if (ret == BLK_STS_OK)
653 trace_nullb_zone_op(cmd, zone_no, zone->cond);
654
655unlock:
656 null_unlock_zone(dev, zone);
657
658 return ret;
659}
660
661blk_status_t null_process_zoned_cmd(struct nullb_cmd *cmd, enum req_op op,
662 sector_t sector, sector_t nr_sectors)
663{
664 struct nullb_device *dev;
665 struct nullb_zone *zone;
666 blk_status_t sts;
667
668 switch (op) {
669 case REQ_OP_WRITE:
670 return null_zone_write(cmd, sector, nr_sectors, false);
671 case REQ_OP_ZONE_APPEND:
672 return null_zone_write(cmd, sector, nr_sectors, true);
673 case REQ_OP_ZONE_RESET:
674 case REQ_OP_ZONE_RESET_ALL:
675 case REQ_OP_ZONE_OPEN:
676 case REQ_OP_ZONE_CLOSE:
677 case REQ_OP_ZONE_FINISH:
678 return null_zone_mgmt(cmd, op, sector);
679 default:
680 dev = cmd->nq->dev;
681 zone = &dev->zones[null_zone_no(dev, sector)];
682 if (zone->cond == BLK_ZONE_COND_OFFLINE)
683 return BLK_STS_IOERR;
684
685 null_lock_zone(dev, zone);
686 sts = null_process_cmd(cmd, op, sector, nr_sectors);
687 null_unlock_zone(dev, zone);
688 return sts;
689 }
690}
691
692/*
693 * Set a zone in the read-only or offline condition.
694 */
695static void null_set_zone_cond(struct nullb_device *dev,
696 struct nullb_zone *zone, enum blk_zone_cond cond)
697{
698 if (WARN_ON_ONCE(cond != BLK_ZONE_COND_READONLY &&
699 cond != BLK_ZONE_COND_OFFLINE))
700 return;
701
702 null_lock_zone(dev, zone);
703
704 /*
705 * If the read-only condition is requested again to zones already in
706 * read-only condition, restore back normal empty condition. Do the same
707 * if the offline condition is requested for offline zones. Otherwise,
708 * set the specified zone condition to the zones. Finish the zones
709 * beforehand to free up zone resources.
710 */
711 if (zone->cond == cond) {
712 zone->cond = BLK_ZONE_COND_EMPTY;
713 zone->wp = zone->start;
714 if (dev->memory_backed)
715 null_handle_discard(dev, zone->start, zone->len);
716 } else {
717 if (zone->cond != BLK_ZONE_COND_READONLY &&
718 zone->cond != BLK_ZONE_COND_OFFLINE)
719 null_finish_zone(dev, zone);
720 zone->cond = cond;
721 zone->wp = (sector_t)-1;
722 }
723
724 null_unlock_zone(dev, zone);
725}
726
727/*
728 * Identify a zone from the sector written to configfs file. Then set zone
729 * condition to the zone.
730 */
731ssize_t zone_cond_store(struct nullb_device *dev, const char *page,
732 size_t count, enum blk_zone_cond cond)
733{
734 unsigned long long sector;
735 unsigned int zone_no;
736 int ret;
737
738 if (!dev->zoned) {
739 pr_err("null_blk device is not zoned\n");
740 return -EINVAL;
741 }
742
743 if (!dev->zones) {
744 pr_err("null_blk device is not yet powered\n");
745 return -EINVAL;
746 }
747
748 ret = kstrtoull(page, 0, §or);
749 if (ret < 0)
750 return ret;
751
752 zone_no = null_zone_no(dev, sector);
753 if (zone_no >= dev->nr_zones) {
754 pr_err("Sector out of range\n");
755 return -EINVAL;
756 }
757
758 if (dev->zones[zone_no].type == BLK_ZONE_TYPE_CONVENTIONAL) {
759 pr_err("Can not change condition of conventional zones\n");
760 return -EINVAL;
761 }
762
763 null_set_zone_cond(dev, &dev->zones[zone_no], cond);
764
765 return count;
766}