xref: /linux/drivers/block/null_blk/zoned.c (revision 55ab7e14222e5f0b0fd9f7711ca391d2924b35e3)
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 
12 #define NULL_ZONE_INVALID_WP	((sector_t)-1)
13 
mb_to_sects(unsigned long mb)14 static inline sector_t mb_to_sects(unsigned long mb)
15 {
16 	return ((sector_t)mb * SZ_1M) >> SECTOR_SHIFT;
17 }
18 
null_zone_no(struct nullb_device * dev,sector_t sect)19 static inline unsigned int null_zone_no(struct nullb_device *dev, sector_t sect)
20 {
21 	if (WARN_ON_ONCE(!dev->zone_size_sects))
22 		return 0;
23 	return sect >> ilog2(dev->zone_size_sects);
24 }
25 
null_init_zone_lock(struct nullb_device * dev,struct nullb_zone * zone)26 static inline void null_init_zone_lock(struct nullb_device *dev,
27 				       struct nullb_zone *zone)
28 {
29 	if (!dev->memory_backed)
30 		spin_lock_init(&zone->spinlock);
31 	else
32 		mutex_init(&zone->mutex);
33 }
34 
null_lock_zone(struct nullb_device * dev,struct nullb_zone * zone)35 static inline void null_lock_zone(struct nullb_device *dev,
36 				  struct nullb_zone *zone)
37 {
38 	if (!dev->memory_backed)
39 		spin_lock_irq(&zone->spinlock);
40 	else
41 		mutex_lock(&zone->mutex);
42 }
43 
null_unlock_zone(struct nullb_device * dev,struct nullb_zone * zone)44 static inline void null_unlock_zone(struct nullb_device *dev,
45 				    struct nullb_zone *zone)
46 {
47 	if (!dev->memory_backed)
48 		spin_unlock_irq(&zone->spinlock);
49 	else
50 		mutex_unlock(&zone->mutex);
51 }
52 
null_init_zoned_dev(struct nullb_device * dev,struct queue_limits * lim)53 int null_init_zoned_dev(struct nullb_device *dev,
54 			struct queue_limits *lim)
55 {
56 	sector_t dev_capacity_sects, zone_capacity_sects;
57 	struct nullb_zone *zone;
58 	sector_t sector = 0;
59 	unsigned int i;
60 
61 	if (!dev->zone_size || !is_power_of_2(dev->zone_size)) {
62 		pr_err("zone_size must be non-zero power-of-two\n");
63 		return -EINVAL;
64 	}
65 	if (dev->zone_size > dev->size) {
66 		pr_err("Zone size larger than device capacity\n");
67 		return -EINVAL;
68 	}
69 
70 	if (!dev->zone_capacity)
71 		dev->zone_capacity = dev->zone_size;
72 
73 	if (dev->zone_capacity > dev->zone_size) {
74 		pr_err("zone capacity (%lu MB) larger than zone size (%lu MB)\n",
75 		       dev->zone_capacity, dev->zone_size);
76 		return -EINVAL;
77 	}
78 
79 	/*
80 	 * If a smaller zone capacity was requested, do not allow a smaller last
81 	 * zone at the same time as such zone configuration does not correspond
82 	 * to any real zoned device.
83 	 */
84 	if (dev->zone_capacity != dev->zone_size &&
85 	    dev->size & (dev->zone_size - 1)) {
86 		pr_err("A smaller last zone is not allowed with zone capacity smaller than zone size.\n");
87 		return -EINVAL;
88 	}
89 
90 	zone_capacity_sects = mb_to_sects(dev->zone_capacity);
91 	dev_capacity_sects = mb_to_sects(dev->size);
92 	dev->zone_size_sects = mb_to_sects(dev->zone_size);
93 	if (!dev->zone_size_sects) {
94 		pr_err("zone_size too large or too small, leads to zero sectors\n");
95 		return -EINVAL;
96 	}
97 	dev->nr_zones = round_up(dev_capacity_sects, dev->zone_size_sects)
98 		>> ilog2(dev->zone_size_sects);
99 
100 	dev->zones = kvmalloc_objs(struct nullb_zone, dev->nr_zones,
101 				   GFP_KERNEL | __GFP_ZERO);
102 	if (!dev->zones)
103 		return -ENOMEM;
104 
105 	spin_lock_init(&dev->zone_res_lock);
106 
107 	if (dev->zone_nr_conv >= dev->nr_zones) {
108 		dev->zone_nr_conv = dev->nr_zones - 1;
109 		pr_info("changed the number of conventional zones to %u",
110 			dev->zone_nr_conv);
111 	}
112 
113 	dev->zone_append_max_sectors =
114 		min(ALIGN_DOWN(dev->zone_append_max_sectors,
115 			       dev->blocksize >> SECTOR_SHIFT),
116 		    zone_capacity_sects);
117 
118 	/* Max active zones has to be < nbr of seq zones in order to be enforceable */
119 	if (dev->zone_max_active >= dev->nr_zones - dev->zone_nr_conv) {
120 		dev->zone_max_active = 0;
121 		pr_info("zone_max_active limit disabled, limit >= zone count\n");
122 	}
123 
124 	/* Max open zones has to be <= max active zones */
125 	if (dev->zone_max_active && dev->zone_max_open > dev->zone_max_active) {
126 		dev->zone_max_open = dev->zone_max_active;
127 		pr_info("changed the maximum number of open zones to %u\n",
128 			dev->zone_max_open);
129 	} else if (dev->zone_max_open >= dev->nr_zones - dev->zone_nr_conv) {
130 		dev->zone_max_open = 0;
131 		pr_info("zone_max_open limit disabled, limit >= zone count\n");
132 	}
133 	dev->need_zone_res_mgmt = dev->zone_max_active || dev->zone_max_open;
134 	dev->imp_close_zone_no = dev->zone_nr_conv;
135 
136 	for (i = 0; i <  dev->zone_nr_conv; i++) {
137 		zone = &dev->zones[i];
138 
139 		null_init_zone_lock(dev, zone);
140 		zone->start = sector;
141 		zone->len = dev->zone_size_sects;
142 		zone->capacity = zone->len;
143 		zone->wp = zone->start + zone->len;
144 		zone->type = BLK_ZONE_TYPE_CONVENTIONAL;
145 		zone->cond = BLK_ZONE_COND_NOT_WP;
146 
147 		sector += dev->zone_size_sects;
148 	}
149 
150 	for (i = dev->zone_nr_conv; i < dev->nr_zones; i++) {
151 		zone = &dev->zones[i];
152 
153 		null_init_zone_lock(dev, zone);
154 		zone->start = sector;
155 		if (zone->start + dev->zone_size_sects > dev_capacity_sects)
156 			zone->len = dev_capacity_sects - zone->start;
157 		else
158 			zone->len = dev->zone_size_sects;
159 		zone->capacity =
160 			min_t(sector_t, zone->len, zone_capacity_sects);
161 		zone->type = BLK_ZONE_TYPE_SEQWRITE_REQ;
162 		if (dev->zone_full) {
163 			zone->cond = BLK_ZONE_COND_FULL;
164 			zone->wp = zone->start + zone->capacity;
165 		} else{
166 			zone->cond = BLK_ZONE_COND_EMPTY;
167 			zone->wp = zone->start;
168 		}
169 
170 		sector += dev->zone_size_sects;
171 	}
172 
173 	lim->features |= BLK_FEAT_ZONED;
174 	lim->chunk_sectors = dev->zone_size_sects;
175 	lim->max_hw_zone_append_sectors = dev->zone_append_max_sectors;
176 	lim->max_open_zones = dev->zone_max_open;
177 	lim->max_active_zones = dev->zone_max_active;
178 	return 0;
179 }
180 
null_register_zoned_dev(struct nullb * nullb)181 int null_register_zoned_dev(struct nullb *nullb)
182 {
183 	struct request_queue *q = nullb->q;
184 	struct gendisk *disk = nullb->disk;
185 
186 	pr_info("%s: using %s zone append\n",
187 		disk->disk_name,
188 		queue_emulates_zone_append(q) ? "emulated" : "native");
189 
190 	return blk_revalidate_disk_zones(disk);
191 }
192 
null_free_zoned_dev(struct nullb_device * dev)193 void null_free_zoned_dev(struct nullb_device *dev)
194 {
195 	kvfree(dev->zones);
196 	dev->zones = NULL;
197 }
198 
null_report_zones(struct gendisk * disk,sector_t sector,unsigned int nr_zones,struct blk_report_zones_args * args)199 int null_report_zones(struct gendisk *disk, sector_t sector,
200 		unsigned int nr_zones, struct blk_report_zones_args *args)
201 {
202 	struct nullb *nullb = disk->private_data;
203 	struct nullb_device *dev = nullb->dev;
204 	unsigned int first_zone, i;
205 	struct nullb_zone *zone;
206 	struct blk_zone blkz;
207 	int error;
208 
209 	first_zone = null_zone_no(dev, sector);
210 	if (first_zone >= dev->nr_zones)
211 		return 0;
212 
213 	nr_zones = min(nr_zones, dev->nr_zones - first_zone);
214 	trace_nullb_report_zones(nullb, nr_zones);
215 
216 	memset(&blkz, 0, sizeof(struct blk_zone));
217 	zone = &dev->zones[first_zone];
218 	for (i = 0; i < nr_zones; i++, zone++) {
219 		/*
220 		 * Stacked DM target drivers will remap the zone information by
221 		 * modifying the zone information passed to the report callback.
222 		 * So use a local copy to avoid corruption of the device zone
223 		 * array.
224 		 */
225 		null_lock_zone(dev, zone);
226 		blkz.start = zone->start;
227 		blkz.len = zone->len;
228 		blkz.wp = zone->wp;
229 		blkz.type = zone->type;
230 		blkz.cond = zone->cond;
231 		blkz.capacity = zone->capacity;
232 		null_unlock_zone(dev, zone);
233 
234 		error = disk_report_zone(disk, &blkz, i, args);
235 		if (error)
236 			return error;
237 	}
238 
239 	return nr_zones;
240 }
241 
242 /*
243  * This is called in the case of memory backing from null_process_cmd()
244  * with the target zone already locked.
245  */
null_zone_valid_read_len(struct nullb * nullb,sector_t sector,unsigned int len)246 size_t null_zone_valid_read_len(struct nullb *nullb,
247 				sector_t sector, unsigned int len)
248 {
249 	struct nullb_device *dev = nullb->dev;
250 	struct nullb_zone *zone = &dev->zones[null_zone_no(dev, sector)];
251 	unsigned int nr_sectors = DIV_ROUND_UP(len, SECTOR_SIZE);
252 
253 	/* Read must be below the write pointer position */
254 	if (zone->type == BLK_ZONE_TYPE_CONVENTIONAL ||
255 	    sector + nr_sectors <= zone->wp)
256 		return len;
257 
258 	if (sector > zone->wp)
259 		return 0;
260 
261 	return (zone->wp - sector) << SECTOR_SHIFT;
262 }
263 
null_close_imp_open_zone(struct nullb_device * dev)264 static void null_close_imp_open_zone(struct nullb_device *dev)
265 {
266 	struct nullb_zone *zone;
267 	unsigned int zno, i;
268 
269 	zno = dev->imp_close_zone_no;
270 	if (zno >= dev->nr_zones)
271 		zno = dev->zone_nr_conv;
272 
273 	for (i = dev->zone_nr_conv; i < dev->nr_zones; i++) {
274 		zone = &dev->zones[zno];
275 		zno++;
276 		if (zno >= dev->nr_zones)
277 			zno = dev->zone_nr_conv;
278 
279 		if (zone->cond == BLK_ZONE_COND_IMP_OPEN) {
280 			dev->nr_zones_imp_open--;
281 			if (zone->wp == zone->start) {
282 				zone->cond = BLK_ZONE_COND_EMPTY;
283 			} else {
284 				zone->cond = BLK_ZONE_COND_CLOSED;
285 				dev->nr_zones_closed++;
286 			}
287 			dev->imp_close_zone_no = zno;
288 			return;
289 		}
290 	}
291 }
292 
null_check_active(struct nullb_device * dev)293 static blk_status_t null_check_active(struct nullb_device *dev)
294 {
295 	if (!dev->zone_max_active)
296 		return BLK_STS_OK;
297 
298 	if (dev->nr_zones_exp_open + dev->nr_zones_imp_open +
299 			dev->nr_zones_closed < dev->zone_max_active)
300 		return BLK_STS_OK;
301 
302 	return BLK_STS_ZONE_ACTIVE_RESOURCE;
303 }
304 
null_check_open(struct nullb_device * dev)305 static blk_status_t null_check_open(struct nullb_device *dev)
306 {
307 	if (!dev->zone_max_open)
308 		return BLK_STS_OK;
309 
310 	if (dev->nr_zones_exp_open + dev->nr_zones_imp_open < dev->zone_max_open)
311 		return BLK_STS_OK;
312 
313 	if (dev->nr_zones_imp_open) {
314 		if (null_check_active(dev) == BLK_STS_OK) {
315 			null_close_imp_open_zone(dev);
316 			return BLK_STS_OK;
317 		}
318 	}
319 
320 	return BLK_STS_ZONE_OPEN_RESOURCE;
321 }
322 
323 /*
324  * This function matches the manage open zone resources function in the ZBC standard,
325  * with the addition of max active zones support (added in the ZNS standard).
326  *
327  * The function determines if a zone can transition to implicit open or explicit open,
328  * while maintaining the max open zone (and max active zone) limit(s). It may close an
329  * implicit open zone in order to make additional zone resources available.
330  *
331  * ZBC states that an implicit open zone shall be closed only if there is not
332  * room within the open limit. However, with the addition of an active limit,
333  * it is not certain that closing an implicit open zone will allow a new zone
334  * to be opened, since we might already be at the active limit capacity.
335  */
null_check_zone_resources(struct nullb_device * dev,struct nullb_zone * zone)336 static blk_status_t null_check_zone_resources(struct nullb_device *dev,
337 					      struct nullb_zone *zone)
338 {
339 	blk_status_t ret;
340 
341 	switch (zone->cond) {
342 	case BLK_ZONE_COND_EMPTY:
343 		ret = null_check_active(dev);
344 		if (ret != BLK_STS_OK)
345 			return ret;
346 		fallthrough;
347 	case BLK_ZONE_COND_CLOSED:
348 		return null_check_open(dev);
349 	default:
350 		/* Should never be called for other states */
351 		WARN_ON(1);
352 		return BLK_STS_IOERR;
353 	}
354 }
355 
null_zone_write(struct nullb_cmd * cmd,sector_t sector,unsigned int nr_sectors,bool append)356 static blk_status_t null_zone_write(struct nullb_cmd *cmd, sector_t sector,
357 				    unsigned int nr_sectors, bool append)
358 {
359 	struct nullb_device *dev = cmd->nq->dev;
360 	unsigned int zno = null_zone_no(dev, sector);
361 	struct nullb_zone *zone = &dev->zones[zno];
362 	blk_status_t badblocks_ret = BLK_STS_OK;
363 	blk_status_t ret;
364 
365 	trace_nullb_zone_op(cmd, zno, zone->cond);
366 
367 	if (zone->type == BLK_ZONE_TYPE_CONVENTIONAL) {
368 		if (append)
369 			return BLK_STS_IOERR;
370 		return null_process_cmd(cmd, REQ_OP_WRITE, sector, nr_sectors);
371 	}
372 
373 	null_lock_zone(dev, zone);
374 
375 	/*
376 	 * Regular writes must be at the write pointer position. Zone append
377 	 * writes are automatically issued at the write pointer and the position
378 	 * returned using the request sector. Note that we do not check the zone
379 	 * condition because for FULL, READONLY and OFFLINE zones, the sector
380 	 * check against the zone write pointer will always result in failing
381 	 * the command.
382 	 */
383 	if (append) {
384 		if (WARN_ON_ONCE(!dev->zone_append_max_sectors) ||
385 		    zone->wp == NULL_ZONE_INVALID_WP) {
386 			ret = BLK_STS_IOERR;
387 			goto unlock_zone;
388 		}
389 		sector = zone->wp;
390 		blk_mq_rq_from_pdu(cmd)->__sector = sector;
391 	}
392 
393 	if (sector != zone->wp ||
394 	    zone->wp + nr_sectors > zone->start + zone->capacity) {
395 		ret = BLK_STS_IOERR;
396 		goto unlock_zone;
397 	}
398 
399 	if (zone->cond == BLK_ZONE_COND_CLOSED ||
400 	    zone->cond == BLK_ZONE_COND_EMPTY) {
401 		if (dev->need_zone_res_mgmt) {
402 			spin_lock(&dev->zone_res_lock);
403 
404 			ret = null_check_zone_resources(dev, zone);
405 			if (ret != BLK_STS_OK) {
406 				spin_unlock(&dev->zone_res_lock);
407 				goto unlock_zone;
408 			}
409 			if (zone->cond == BLK_ZONE_COND_CLOSED) {
410 				dev->nr_zones_closed--;
411 				dev->nr_zones_imp_open++;
412 			} else if (zone->cond == BLK_ZONE_COND_EMPTY) {
413 				dev->nr_zones_imp_open++;
414 			}
415 
416 			spin_unlock(&dev->zone_res_lock);
417 		}
418 
419 		zone->cond = BLK_ZONE_COND_IMP_OPEN;
420 	}
421 
422 	if (dev->badblocks.shift != -1) {
423 		badblocks_ret = null_handle_badblocks(cmd, sector, &nr_sectors);
424 		if (badblocks_ret != BLK_STS_OK && !nr_sectors) {
425 			ret = badblocks_ret;
426 			goto unlock_zone;
427 		}
428 	}
429 
430 	if (dev->memory_backed) {
431 		ret = null_handle_memory_backed(cmd, REQ_OP_WRITE, sector,
432 						nr_sectors);
433 		if (ret != BLK_STS_OK)
434 			goto unlock_zone;
435 	}
436 
437 	zone->wp += nr_sectors;
438 	if (zone->wp == zone->start + zone->capacity) {
439 		if (dev->need_zone_res_mgmt) {
440 			spin_lock(&dev->zone_res_lock);
441 			if (zone->cond == BLK_ZONE_COND_EXP_OPEN)
442 				dev->nr_zones_exp_open--;
443 			else if (zone->cond == BLK_ZONE_COND_IMP_OPEN)
444 				dev->nr_zones_imp_open--;
445 			spin_unlock(&dev->zone_res_lock);
446 		}
447 		zone->cond = BLK_ZONE_COND_FULL;
448 	}
449 
450 	ret = badblocks_ret;
451 
452 unlock_zone:
453 	null_unlock_zone(dev, zone);
454 
455 	return ret;
456 }
457 
null_open_zone(struct nullb_device * dev,struct nullb_zone * zone)458 static blk_status_t null_open_zone(struct nullb_device *dev,
459 				   struct nullb_zone *zone)
460 {
461 	blk_status_t ret = BLK_STS_OK;
462 
463 	if (zone->type == BLK_ZONE_TYPE_CONVENTIONAL)
464 		return BLK_STS_IOERR;
465 
466 	switch (zone->cond) {
467 	case BLK_ZONE_COND_EXP_OPEN:
468 		/* Open operation on exp open is not an error */
469 		return BLK_STS_OK;
470 	case BLK_ZONE_COND_EMPTY:
471 	case BLK_ZONE_COND_IMP_OPEN:
472 	case BLK_ZONE_COND_CLOSED:
473 		break;
474 	case BLK_ZONE_COND_FULL:
475 	default:
476 		return BLK_STS_IOERR;
477 	}
478 
479 	if (dev->need_zone_res_mgmt) {
480 		spin_lock(&dev->zone_res_lock);
481 
482 		switch (zone->cond) {
483 		case BLK_ZONE_COND_EMPTY:
484 			ret = null_check_zone_resources(dev, zone);
485 			if (ret != BLK_STS_OK) {
486 				spin_unlock(&dev->zone_res_lock);
487 				return ret;
488 			}
489 			break;
490 		case BLK_ZONE_COND_IMP_OPEN:
491 			dev->nr_zones_imp_open--;
492 			break;
493 		case BLK_ZONE_COND_CLOSED:
494 			ret = null_check_zone_resources(dev, zone);
495 			if (ret != BLK_STS_OK) {
496 				spin_unlock(&dev->zone_res_lock);
497 				return ret;
498 			}
499 			dev->nr_zones_closed--;
500 			break;
501 		default:
502 			break;
503 		}
504 
505 		dev->nr_zones_exp_open++;
506 
507 		spin_unlock(&dev->zone_res_lock);
508 	}
509 
510 	zone->cond = BLK_ZONE_COND_EXP_OPEN;
511 
512 	return BLK_STS_OK;
513 }
514 
null_close_zone(struct nullb_device * dev,struct nullb_zone * zone)515 static blk_status_t null_close_zone(struct nullb_device *dev,
516 				    struct nullb_zone *zone)
517 {
518 	if (zone->type == BLK_ZONE_TYPE_CONVENTIONAL)
519 		return BLK_STS_IOERR;
520 
521 	switch (zone->cond) {
522 	case BLK_ZONE_COND_CLOSED:
523 		/* close operation on closed is not an error */
524 		return BLK_STS_OK;
525 	case BLK_ZONE_COND_IMP_OPEN:
526 	case BLK_ZONE_COND_EXP_OPEN:
527 		break;
528 	case BLK_ZONE_COND_EMPTY:
529 	case BLK_ZONE_COND_FULL:
530 	default:
531 		return BLK_STS_IOERR;
532 	}
533 
534 	if (dev->need_zone_res_mgmt) {
535 		spin_lock(&dev->zone_res_lock);
536 
537 		switch (zone->cond) {
538 		case BLK_ZONE_COND_IMP_OPEN:
539 			dev->nr_zones_imp_open--;
540 			break;
541 		case BLK_ZONE_COND_EXP_OPEN:
542 			dev->nr_zones_exp_open--;
543 			break;
544 		default:
545 			break;
546 		}
547 
548 		if (zone->wp > zone->start)
549 			dev->nr_zones_closed++;
550 
551 		spin_unlock(&dev->zone_res_lock);
552 	}
553 
554 	if (zone->wp == zone->start)
555 		zone->cond = BLK_ZONE_COND_EMPTY;
556 	else
557 		zone->cond = BLK_ZONE_COND_CLOSED;
558 
559 	return BLK_STS_OK;
560 }
561 
null_finish_zone(struct nullb_device * dev,struct nullb_zone * zone)562 static blk_status_t null_finish_zone(struct nullb_device *dev,
563 				     struct nullb_zone *zone)
564 {
565 	blk_status_t ret = BLK_STS_OK;
566 
567 	if (zone->type == BLK_ZONE_TYPE_CONVENTIONAL)
568 		return BLK_STS_IOERR;
569 
570 	if (dev->need_zone_res_mgmt) {
571 		spin_lock(&dev->zone_res_lock);
572 
573 		switch (zone->cond) {
574 		case BLK_ZONE_COND_FULL:
575 			/* Finish operation on full is not an error */
576 			spin_unlock(&dev->zone_res_lock);
577 			return BLK_STS_OK;
578 		case BLK_ZONE_COND_EMPTY:
579 			ret = null_check_zone_resources(dev, zone);
580 			if (ret != BLK_STS_OK) {
581 				spin_unlock(&dev->zone_res_lock);
582 				return ret;
583 			}
584 			break;
585 		case BLK_ZONE_COND_IMP_OPEN:
586 			dev->nr_zones_imp_open--;
587 			break;
588 		case BLK_ZONE_COND_EXP_OPEN:
589 			dev->nr_zones_exp_open--;
590 			break;
591 		case BLK_ZONE_COND_CLOSED:
592 			ret = null_check_zone_resources(dev, zone);
593 			if (ret != BLK_STS_OK) {
594 				spin_unlock(&dev->zone_res_lock);
595 				return ret;
596 			}
597 			dev->nr_zones_closed--;
598 			break;
599 		default:
600 			spin_unlock(&dev->zone_res_lock);
601 			return BLK_STS_IOERR;
602 		}
603 
604 		spin_unlock(&dev->zone_res_lock);
605 	}
606 
607 	zone->cond = BLK_ZONE_COND_FULL;
608 	zone->wp = zone->start + zone->len;
609 
610 	return BLK_STS_OK;
611 }
612 
null_reset_zone(struct nullb_device * dev,struct nullb_zone * zone)613 static blk_status_t null_reset_zone(struct nullb_device *dev,
614 				    struct nullb_zone *zone)
615 {
616 	if (zone->type == BLK_ZONE_TYPE_CONVENTIONAL)
617 		return BLK_STS_IOERR;
618 
619 	if (dev->need_zone_res_mgmt) {
620 		spin_lock(&dev->zone_res_lock);
621 
622 		switch (zone->cond) {
623 		case BLK_ZONE_COND_IMP_OPEN:
624 			dev->nr_zones_imp_open--;
625 			break;
626 		case BLK_ZONE_COND_EXP_OPEN:
627 			dev->nr_zones_exp_open--;
628 			break;
629 		case BLK_ZONE_COND_CLOSED:
630 			dev->nr_zones_closed--;
631 			break;
632 		case BLK_ZONE_COND_EMPTY:
633 		case BLK_ZONE_COND_FULL:
634 			break;
635 		default:
636 			spin_unlock(&dev->zone_res_lock);
637 			return BLK_STS_IOERR;
638 		}
639 
640 		spin_unlock(&dev->zone_res_lock);
641 	}
642 
643 	zone->cond = BLK_ZONE_COND_EMPTY;
644 	zone->wp = zone->start;
645 
646 	if (dev->memory_backed)
647 		return null_handle_discard(dev, zone->start, zone->len);
648 
649 	return BLK_STS_OK;
650 }
651 
null_zone_mgmt(struct nullb_cmd * cmd,enum req_op op,sector_t sector)652 static blk_status_t null_zone_mgmt(struct nullb_cmd *cmd, enum req_op op,
653 				   sector_t sector)
654 {
655 	struct nullb_device *dev = cmd->nq->dev;
656 	unsigned int zone_no;
657 	struct nullb_zone *zone;
658 	blk_status_t ret;
659 	size_t i;
660 
661 	if (op == REQ_OP_ZONE_RESET_ALL) {
662 		for (i = dev->zone_nr_conv; i < dev->nr_zones; i++) {
663 			zone = &dev->zones[i];
664 			null_lock_zone(dev, zone);
665 			if (zone->cond != BLK_ZONE_COND_EMPTY &&
666 			    zone->cond != BLK_ZONE_COND_READONLY &&
667 			    zone->cond != BLK_ZONE_COND_OFFLINE) {
668 				null_reset_zone(dev, zone);
669 				trace_nullb_zone_op(cmd, i, zone->cond);
670 			}
671 			null_unlock_zone(dev, zone);
672 		}
673 		return BLK_STS_OK;
674 	}
675 
676 	zone_no = null_zone_no(dev, sector);
677 	zone = &dev->zones[zone_no];
678 
679 	null_lock_zone(dev, zone);
680 
681 	if (zone->cond == BLK_ZONE_COND_READONLY ||
682 	    zone->cond == BLK_ZONE_COND_OFFLINE) {
683 		ret = BLK_STS_IOERR;
684 		goto unlock;
685 	}
686 
687 	switch (op) {
688 	case REQ_OP_ZONE_RESET:
689 		ret = null_reset_zone(dev, zone);
690 		break;
691 	case REQ_OP_ZONE_OPEN:
692 		ret = null_open_zone(dev, zone);
693 		break;
694 	case REQ_OP_ZONE_CLOSE:
695 		ret = null_close_zone(dev, zone);
696 		break;
697 	case REQ_OP_ZONE_FINISH:
698 		ret = null_finish_zone(dev, zone);
699 		break;
700 	default:
701 		ret = BLK_STS_NOTSUPP;
702 		break;
703 	}
704 
705 	if (ret == BLK_STS_OK)
706 		trace_nullb_zone_op(cmd, zone_no, zone->cond);
707 
708 unlock:
709 	null_unlock_zone(dev, zone);
710 
711 	return ret;
712 }
713 
null_process_zoned_cmd(struct nullb_cmd * cmd,enum req_op op,sector_t sector,sector_t nr_sectors)714 blk_status_t null_process_zoned_cmd(struct nullb_cmd *cmd, enum req_op op,
715 				    sector_t sector, sector_t nr_sectors)
716 {
717 	struct nullb_device *dev;
718 	struct nullb_zone *zone;
719 	blk_status_t sts;
720 
721 	switch (op) {
722 	case REQ_OP_WRITE:
723 		return null_zone_write(cmd, sector, nr_sectors, false);
724 	case REQ_OP_ZONE_APPEND:
725 		return null_zone_write(cmd, sector, nr_sectors, true);
726 	case REQ_OP_ZONE_RESET:
727 	case REQ_OP_ZONE_RESET_ALL:
728 	case REQ_OP_ZONE_OPEN:
729 	case REQ_OP_ZONE_CLOSE:
730 	case REQ_OP_ZONE_FINISH:
731 		return null_zone_mgmt(cmd, op, sector);
732 	default:
733 		dev = cmd->nq->dev;
734 		zone = &dev->zones[null_zone_no(dev, sector)];
735 		if (zone->cond == BLK_ZONE_COND_OFFLINE)
736 			return BLK_STS_IOERR;
737 
738 		null_lock_zone(dev, zone);
739 		sts = null_process_cmd(cmd, op, sector, nr_sectors);
740 		null_unlock_zone(dev, zone);
741 		return sts;
742 	}
743 }
744 
745 /*
746  * Set a zone in the read-only or offline condition.
747  */
null_set_zone_cond(struct nullb_device * dev,struct nullb_zone * zone,enum blk_zone_cond cond)748 static void null_set_zone_cond(struct nullb_device *dev,
749 			       struct nullb_zone *zone, enum blk_zone_cond cond)
750 {
751 	if (WARN_ON_ONCE(cond != BLK_ZONE_COND_READONLY &&
752 			 cond != BLK_ZONE_COND_OFFLINE))
753 		return;
754 
755 	null_lock_zone(dev, zone);
756 
757 	/*
758 	 * If the read-only condition is requested again to zones already in
759 	 * read-only condition, restore back normal empty condition. Do the same
760 	 * if the offline condition is requested for offline zones. Otherwise,
761 	 * set the specified zone condition to the zones. Finish the zones
762 	 * beforehand to free up zone resources.
763 	 */
764 	if (zone->cond == cond) {
765 		zone->cond = BLK_ZONE_COND_EMPTY;
766 		zone->wp = zone->start;
767 		if (dev->memory_backed)
768 			null_handle_discard(dev, zone->start, zone->len);
769 	} else {
770 		if (zone->cond != BLK_ZONE_COND_READONLY &&
771 		    zone->cond != BLK_ZONE_COND_OFFLINE)
772 			null_finish_zone(dev, zone);
773 		zone->cond = cond;
774 		zone->wp = NULL_ZONE_INVALID_WP;
775 	}
776 
777 	null_unlock_zone(dev, zone);
778 }
779 
780 /*
781  * Identify a zone from the sector written to configfs file. Then set zone
782  * condition to the zone.
783  */
zone_cond_store(struct nullb_device * dev,const char * page,size_t count,enum blk_zone_cond cond)784 ssize_t zone_cond_store(struct nullb_device *dev, const char *page,
785 			size_t count, enum blk_zone_cond cond)
786 {
787 	unsigned long long sector;
788 	unsigned int zone_no;
789 	int ret;
790 
791 	if (!dev->zoned) {
792 		pr_err("null_blk device is not zoned\n");
793 		return -EINVAL;
794 	}
795 
796 	if (!dev->zones) {
797 		pr_err("null_blk device is not yet powered\n");
798 		return -EINVAL;
799 	}
800 
801 	ret = kstrtoull(page, 0, &sector);
802 	if (ret < 0)
803 		return ret;
804 
805 	zone_no = null_zone_no(dev, sector);
806 	if (zone_no >= dev->nr_zones) {
807 		pr_err("Sector out of range\n");
808 		return -EINVAL;
809 	}
810 
811 	if (dev->zones[zone_no].type == BLK_ZONE_TYPE_CONVENTIONAL) {
812 		pr_err("Can not change condition of conventional zones\n");
813 		return -EINVAL;
814 	}
815 
816 	null_set_zone_cond(dev, &dev->zones[zone_no], cond);
817 
818 	return count;
819 }
820