1 // SPDX-License-Identifier: GPL-2.0
2 
3 #include <linux/bitops.h>
4 #include <linux/slab.h>
5 #include <linux/blkdev.h>
6 #include <linux/sched/mm.h>
7 #include <linux/atomic.h>
8 #include <linux/vmalloc.h>
9 #include "ctree.h"
10 #include "volumes.h"
11 #include "zoned.h"
12 #include "rcu-string.h"
13 #include "disk-io.h"
14 #include "block-group.h"
15 #include "dev-replace.h"
16 #include "space-info.h"
17 #include "fs.h"
18 #include "accessors.h"
19 #include "bio.h"
20 
21 /* Maximum number of zones to report per blkdev_report_zones() call */
22 #define BTRFS_REPORT_NR_ZONES   4096
23 /* Invalid allocation pointer value for missing devices */
24 #define WP_MISSING_DEV ((u64)-1)
25 /* Pseudo write pointer value for conventional zone */
26 #define WP_CONVENTIONAL ((u64)-2)
27 
28 /*
29  * Location of the first zone of superblock logging zone pairs.
30  *
31  * - primary superblock:    0B (zone 0)
32  * - first copy:          512G (zone starting at that offset)
33  * - second copy:           4T (zone starting at that offset)
34  */
35 #define BTRFS_SB_LOG_PRIMARY_OFFSET	(0ULL)
36 #define BTRFS_SB_LOG_FIRST_OFFSET	(512ULL * SZ_1G)
37 #define BTRFS_SB_LOG_SECOND_OFFSET	(4096ULL * SZ_1G)
38 
39 #define BTRFS_SB_LOG_FIRST_SHIFT	const_ilog2(BTRFS_SB_LOG_FIRST_OFFSET)
40 #define BTRFS_SB_LOG_SECOND_SHIFT	const_ilog2(BTRFS_SB_LOG_SECOND_OFFSET)
41 
42 /* Number of superblock log zones */
43 #define BTRFS_NR_SB_LOG_ZONES 2
44 
45 /*
46  * Minimum of active zones we need:
47  *
48  * - BTRFS_SUPER_MIRROR_MAX zones for superblock mirrors
49  * - 3 zones to ensure at least one zone per SYSTEM, META and DATA block group
50  * - 1 zone for tree-log dedicated block group
51  * - 1 zone for relocation
52  */
53 #define BTRFS_MIN_ACTIVE_ZONES		(BTRFS_SUPER_MIRROR_MAX + 5)
54 
55 /*
56  * Minimum / maximum supported zone size. Currently, SMR disks have a zone
57  * size of 256MiB, and we are expecting ZNS drives to be in the 1-4GiB range.
58  * We do not expect the zone size to become larger than 8GiB or smaller than
59  * 4MiB in the near future.
60  */
61 #define BTRFS_MAX_ZONE_SIZE		SZ_8G
62 #define BTRFS_MIN_ZONE_SIZE		SZ_4M
63 
64 #define SUPER_INFO_SECTORS	((u64)BTRFS_SUPER_INFO_SIZE >> SECTOR_SHIFT)
65 
66 static void wait_eb_writebacks(struct btrfs_block_group *block_group);
67 static int do_zone_finish(struct btrfs_block_group *block_group, bool fully_written);
68 
sb_zone_is_full(const struct blk_zone * zone)69 static inline bool sb_zone_is_full(const struct blk_zone *zone)
70 {
71 	return (zone->cond == BLK_ZONE_COND_FULL) ||
72 		(zone->wp + SUPER_INFO_SECTORS > zone->start + zone->capacity);
73 }
74 
copy_zone_info_cb(struct blk_zone * zone,unsigned int idx,void * data)75 static int copy_zone_info_cb(struct blk_zone *zone, unsigned int idx, void *data)
76 {
77 	struct blk_zone *zones = data;
78 
79 	memcpy(&zones[idx], zone, sizeof(*zone));
80 
81 	return 0;
82 }
83 
sb_write_pointer(struct block_device * bdev,struct blk_zone * zones,u64 * wp_ret)84 static int sb_write_pointer(struct block_device *bdev, struct blk_zone *zones,
85 			    u64 *wp_ret)
86 {
87 	bool empty[BTRFS_NR_SB_LOG_ZONES];
88 	bool full[BTRFS_NR_SB_LOG_ZONES];
89 	sector_t sector;
90 
91 	for (int i = 0; i < BTRFS_NR_SB_LOG_ZONES; i++) {
92 		ASSERT(zones[i].type != BLK_ZONE_TYPE_CONVENTIONAL);
93 		empty[i] = (zones[i].cond == BLK_ZONE_COND_EMPTY);
94 		full[i] = sb_zone_is_full(&zones[i]);
95 	}
96 
97 	/*
98 	 * Possible states of log buffer zones
99 	 *
100 	 *           Empty[0]  In use[0]  Full[0]
101 	 * Empty[1]         *          0        1
102 	 * In use[1]        x          x        1
103 	 * Full[1]          0          0        C
104 	 *
105 	 * Log position:
106 	 *   *: Special case, no superblock is written
107 	 *   0: Use write pointer of zones[0]
108 	 *   1: Use write pointer of zones[1]
109 	 *   C: Compare super blocks from zones[0] and zones[1], use the latest
110 	 *      one determined by generation
111 	 *   x: Invalid state
112 	 */
113 
114 	if (empty[0] && empty[1]) {
115 		/* Special case to distinguish no superblock to read */
116 		*wp_ret = zones[0].start << SECTOR_SHIFT;
117 		return -ENOENT;
118 	} else if (full[0] && full[1]) {
119 		/* Compare two super blocks */
120 		struct address_space *mapping = bdev->bd_mapping;
121 		struct page *page[BTRFS_NR_SB_LOG_ZONES];
122 		struct btrfs_super_block *super[BTRFS_NR_SB_LOG_ZONES];
123 
124 		for (int i = 0; i < BTRFS_NR_SB_LOG_ZONES; i++) {
125 			u64 zone_end = (zones[i].start + zones[i].capacity) << SECTOR_SHIFT;
126 			u64 bytenr = ALIGN_DOWN(zone_end, BTRFS_SUPER_INFO_SIZE) -
127 						BTRFS_SUPER_INFO_SIZE;
128 
129 			page[i] = read_cache_page_gfp(mapping,
130 					bytenr >> PAGE_SHIFT, GFP_NOFS);
131 			if (IS_ERR(page[i])) {
132 				if (i == 1)
133 					btrfs_release_disk_super(super[0]);
134 				return PTR_ERR(page[i]);
135 			}
136 			super[i] = page_address(page[i]);
137 		}
138 
139 		if (btrfs_super_generation(super[0]) >
140 		    btrfs_super_generation(super[1]))
141 			sector = zones[1].start;
142 		else
143 			sector = zones[0].start;
144 
145 		for (int i = 0; i < BTRFS_NR_SB_LOG_ZONES; i++)
146 			btrfs_release_disk_super(super[i]);
147 	} else if (!full[0] && (empty[1] || full[1])) {
148 		sector = zones[0].wp;
149 	} else if (full[0]) {
150 		sector = zones[1].wp;
151 	} else {
152 		return -EUCLEAN;
153 	}
154 	*wp_ret = sector << SECTOR_SHIFT;
155 	return 0;
156 }
157 
158 /*
159  * Get the first zone number of the superblock mirror
160  */
sb_zone_number(int shift,int mirror)161 static inline u32 sb_zone_number(int shift, int mirror)
162 {
163 	u64 zone = U64_MAX;
164 
165 	ASSERT(mirror < BTRFS_SUPER_MIRROR_MAX);
166 	switch (mirror) {
167 	case 0: zone = 0; break;
168 	case 1: zone = 1ULL << (BTRFS_SB_LOG_FIRST_SHIFT - shift); break;
169 	case 2: zone = 1ULL << (BTRFS_SB_LOG_SECOND_SHIFT - shift); break;
170 	}
171 
172 	ASSERT(zone <= U32_MAX);
173 
174 	return (u32)zone;
175 }
176 
zone_start_sector(u32 zone_number,struct block_device * bdev)177 static inline sector_t zone_start_sector(u32 zone_number,
178 					 struct block_device *bdev)
179 {
180 	return (sector_t)zone_number << ilog2(bdev_zone_sectors(bdev));
181 }
182 
zone_start_physical(u32 zone_number,struct btrfs_zoned_device_info * zone_info)183 static inline u64 zone_start_physical(u32 zone_number,
184 				      struct btrfs_zoned_device_info *zone_info)
185 {
186 	return (u64)zone_number << zone_info->zone_size_shift;
187 }
188 
189 /*
190  * Emulate blkdev_report_zones() for a non-zoned device. It slices up the block
191  * device into static sized chunks and fake a conventional zone on each of
192  * them.
193  */
emulate_report_zones(struct btrfs_device * device,u64 pos,struct blk_zone * zones,unsigned int nr_zones)194 static int emulate_report_zones(struct btrfs_device *device, u64 pos,
195 				struct blk_zone *zones, unsigned int nr_zones)
196 {
197 	const sector_t zone_sectors = device->fs_info->zone_size >> SECTOR_SHIFT;
198 	sector_t bdev_size = bdev_nr_sectors(device->bdev);
199 	unsigned int i;
200 
201 	pos >>= SECTOR_SHIFT;
202 	for (i = 0; i < nr_zones; i++) {
203 		zones[i].start = i * zone_sectors + pos;
204 		zones[i].len = zone_sectors;
205 		zones[i].capacity = zone_sectors;
206 		zones[i].wp = zones[i].start + zone_sectors;
207 		zones[i].type = BLK_ZONE_TYPE_CONVENTIONAL;
208 		zones[i].cond = BLK_ZONE_COND_NOT_WP;
209 
210 		if (zones[i].wp >= bdev_size) {
211 			i++;
212 			break;
213 		}
214 	}
215 
216 	return i;
217 }
218 
btrfs_get_dev_zones(struct btrfs_device * device,u64 pos,struct blk_zone * zones,unsigned int * nr_zones)219 static int btrfs_get_dev_zones(struct btrfs_device *device, u64 pos,
220 			       struct blk_zone *zones, unsigned int *nr_zones)
221 {
222 	struct btrfs_zoned_device_info *zinfo = device->zone_info;
223 	int ret;
224 
225 	if (!*nr_zones)
226 		return 0;
227 
228 	if (!bdev_is_zoned(device->bdev)) {
229 		ret = emulate_report_zones(device, pos, zones, *nr_zones);
230 		*nr_zones = ret;
231 		return 0;
232 	}
233 
234 	/* Check cache */
235 	if (zinfo->zone_cache) {
236 		unsigned int i;
237 		u32 zno;
238 
239 		ASSERT(IS_ALIGNED(pos, zinfo->zone_size));
240 		zno = pos >> zinfo->zone_size_shift;
241 		/*
242 		 * We cannot report zones beyond the zone end. So, it is OK to
243 		 * cap *nr_zones to at the end.
244 		 */
245 		*nr_zones = min_t(u32, *nr_zones, zinfo->nr_zones - zno);
246 
247 		for (i = 0; i < *nr_zones; i++) {
248 			struct blk_zone *zone_info;
249 
250 			zone_info = &zinfo->zone_cache[zno + i];
251 			if (!zone_info->len)
252 				break;
253 		}
254 
255 		if (i == *nr_zones) {
256 			/* Cache hit on all the zones */
257 			memcpy(zones, zinfo->zone_cache + zno,
258 			       sizeof(*zinfo->zone_cache) * *nr_zones);
259 			return 0;
260 		}
261 	}
262 
263 	ret = blkdev_report_zones(device->bdev, pos >> SECTOR_SHIFT, *nr_zones,
264 				  copy_zone_info_cb, zones);
265 	if (ret < 0) {
266 		btrfs_err_in_rcu(device->fs_info,
267 				 "zoned: failed to read zone %llu on %s (devid %llu)",
268 				 pos, rcu_str_deref(device->name),
269 				 device->devid);
270 		return ret;
271 	}
272 	*nr_zones = ret;
273 	if (!ret)
274 		return -EIO;
275 
276 	/* Populate cache */
277 	if (zinfo->zone_cache) {
278 		u32 zno = pos >> zinfo->zone_size_shift;
279 
280 		memcpy(zinfo->zone_cache + zno, zones,
281 		       sizeof(*zinfo->zone_cache) * *nr_zones);
282 	}
283 
284 	return 0;
285 }
286 
287 /* The emulated zone size is determined from the size of device extent */
calculate_emulated_zone_size(struct btrfs_fs_info * fs_info)288 static int calculate_emulated_zone_size(struct btrfs_fs_info *fs_info)
289 {
290 	BTRFS_PATH_AUTO_FREE(path);
291 	struct btrfs_root *root = fs_info->dev_root;
292 	struct btrfs_key key;
293 	struct extent_buffer *leaf;
294 	struct btrfs_dev_extent *dext;
295 	int ret = 0;
296 
297 	key.objectid = 1;
298 	key.type = BTRFS_DEV_EXTENT_KEY;
299 	key.offset = 0;
300 
301 	path = btrfs_alloc_path();
302 	if (!path)
303 		return -ENOMEM;
304 
305 	ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
306 	if (ret < 0)
307 		return ret;
308 
309 	if (path->slots[0] >= btrfs_header_nritems(path->nodes[0])) {
310 		ret = btrfs_next_leaf(root, path);
311 		if (ret < 0)
312 			return ret;
313 		/* No dev extents at all? Not good */
314 		if (ret > 0)
315 			return -EUCLEAN;
316 	}
317 
318 	leaf = path->nodes[0];
319 	dext = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_extent);
320 	fs_info->zone_size = btrfs_dev_extent_length(leaf, dext);
321 	return 0;
322 }
323 
btrfs_get_dev_zone_info_all_devices(struct btrfs_fs_info * fs_info)324 int btrfs_get_dev_zone_info_all_devices(struct btrfs_fs_info *fs_info)
325 {
326 	struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
327 	struct btrfs_device *device;
328 	int ret = 0;
329 
330 	/* fs_info->zone_size might not set yet. Use the incomapt flag here. */
331 	if (!btrfs_fs_incompat(fs_info, ZONED))
332 		return 0;
333 
334 	mutex_lock(&fs_devices->device_list_mutex);
335 	list_for_each_entry(device, &fs_devices->devices, dev_list) {
336 		/* We can skip reading of zone info for missing devices */
337 		if (!device->bdev)
338 			continue;
339 
340 		ret = btrfs_get_dev_zone_info(device, true);
341 		if (ret)
342 			break;
343 	}
344 	mutex_unlock(&fs_devices->device_list_mutex);
345 
346 	return ret;
347 }
348 
btrfs_get_dev_zone_info(struct btrfs_device * device,bool populate_cache)349 int btrfs_get_dev_zone_info(struct btrfs_device *device, bool populate_cache)
350 {
351 	struct btrfs_fs_info *fs_info = device->fs_info;
352 	struct btrfs_zoned_device_info *zone_info = NULL;
353 	struct block_device *bdev = device->bdev;
354 	unsigned int max_active_zones;
355 	unsigned int nactive;
356 	sector_t nr_sectors;
357 	sector_t sector = 0;
358 	struct blk_zone *zones = NULL;
359 	unsigned int i, nreported = 0, nr_zones;
360 	sector_t zone_sectors;
361 	char *model, *emulated;
362 	int ret;
363 
364 	/*
365 	 * Cannot use btrfs_is_zoned here, since fs_info::zone_size might not
366 	 * yet be set.
367 	 */
368 	if (!btrfs_fs_incompat(fs_info, ZONED))
369 		return 0;
370 
371 	if (device->zone_info)
372 		return 0;
373 
374 	zone_info = kzalloc(sizeof(*zone_info), GFP_KERNEL);
375 	if (!zone_info)
376 		return -ENOMEM;
377 
378 	device->zone_info = zone_info;
379 
380 	if (!bdev_is_zoned(bdev)) {
381 		if (!fs_info->zone_size) {
382 			ret = calculate_emulated_zone_size(fs_info);
383 			if (ret)
384 				goto out;
385 		}
386 
387 		ASSERT(fs_info->zone_size);
388 		zone_sectors = fs_info->zone_size >> SECTOR_SHIFT;
389 	} else {
390 		zone_sectors = bdev_zone_sectors(bdev);
391 	}
392 
393 	ASSERT(is_power_of_two_u64(zone_sectors));
394 	zone_info->zone_size = zone_sectors << SECTOR_SHIFT;
395 
396 	/* We reject devices with a zone size larger than 8GB */
397 	if (zone_info->zone_size > BTRFS_MAX_ZONE_SIZE) {
398 		btrfs_err_in_rcu(fs_info,
399 		"zoned: %s: zone size %llu larger than supported maximum %llu",
400 				 rcu_str_deref(device->name),
401 				 zone_info->zone_size, BTRFS_MAX_ZONE_SIZE);
402 		ret = -EINVAL;
403 		goto out;
404 	} else if (zone_info->zone_size < BTRFS_MIN_ZONE_SIZE) {
405 		btrfs_err_in_rcu(fs_info,
406 		"zoned: %s: zone size %llu smaller than supported minimum %u",
407 				 rcu_str_deref(device->name),
408 				 zone_info->zone_size, BTRFS_MIN_ZONE_SIZE);
409 		ret = -EINVAL;
410 		goto out;
411 	}
412 
413 	nr_sectors = bdev_nr_sectors(bdev);
414 	zone_info->zone_size_shift = ilog2(zone_info->zone_size);
415 	zone_info->nr_zones = nr_sectors >> ilog2(zone_sectors);
416 	if (!IS_ALIGNED(nr_sectors, zone_sectors))
417 		zone_info->nr_zones++;
418 
419 	max_active_zones = bdev_max_active_zones(bdev);
420 	if (max_active_zones && max_active_zones < BTRFS_MIN_ACTIVE_ZONES) {
421 		btrfs_err_in_rcu(fs_info,
422 "zoned: %s: max active zones %u is too small, need at least %u active zones",
423 				 rcu_str_deref(device->name), max_active_zones,
424 				 BTRFS_MIN_ACTIVE_ZONES);
425 		ret = -EINVAL;
426 		goto out;
427 	}
428 	zone_info->max_active_zones = max_active_zones;
429 
430 	zone_info->seq_zones = bitmap_zalloc(zone_info->nr_zones, GFP_KERNEL);
431 	if (!zone_info->seq_zones) {
432 		ret = -ENOMEM;
433 		goto out;
434 	}
435 
436 	zone_info->empty_zones = bitmap_zalloc(zone_info->nr_zones, GFP_KERNEL);
437 	if (!zone_info->empty_zones) {
438 		ret = -ENOMEM;
439 		goto out;
440 	}
441 
442 	zone_info->active_zones = bitmap_zalloc(zone_info->nr_zones, GFP_KERNEL);
443 	if (!zone_info->active_zones) {
444 		ret = -ENOMEM;
445 		goto out;
446 	}
447 
448 	zones = kvcalloc(BTRFS_REPORT_NR_ZONES, sizeof(struct blk_zone), GFP_KERNEL);
449 	if (!zones) {
450 		ret = -ENOMEM;
451 		goto out;
452 	}
453 
454 	/*
455 	 * Enable zone cache only for a zoned device. On a non-zoned device, we
456 	 * fill the zone info with emulated CONVENTIONAL zones, so no need to
457 	 * use the cache.
458 	 */
459 	if (populate_cache && bdev_is_zoned(device->bdev)) {
460 		zone_info->zone_cache = vcalloc(zone_info->nr_zones,
461 						sizeof(struct blk_zone));
462 		if (!zone_info->zone_cache) {
463 			btrfs_err_in_rcu(device->fs_info,
464 				"zoned: failed to allocate zone cache for %s",
465 				rcu_str_deref(device->name));
466 			ret = -ENOMEM;
467 			goto out;
468 		}
469 	}
470 
471 	/* Get zones type */
472 	nactive = 0;
473 	while (sector < nr_sectors) {
474 		nr_zones = BTRFS_REPORT_NR_ZONES;
475 		ret = btrfs_get_dev_zones(device, sector << SECTOR_SHIFT, zones,
476 					  &nr_zones);
477 		if (ret)
478 			goto out;
479 
480 		for (i = 0; i < nr_zones; i++) {
481 			if (zones[i].type == BLK_ZONE_TYPE_SEQWRITE_REQ)
482 				__set_bit(nreported, zone_info->seq_zones);
483 			switch (zones[i].cond) {
484 			case BLK_ZONE_COND_EMPTY:
485 				__set_bit(nreported, zone_info->empty_zones);
486 				break;
487 			case BLK_ZONE_COND_IMP_OPEN:
488 			case BLK_ZONE_COND_EXP_OPEN:
489 			case BLK_ZONE_COND_CLOSED:
490 				__set_bit(nreported, zone_info->active_zones);
491 				nactive++;
492 				break;
493 			}
494 			nreported++;
495 		}
496 		sector = zones[nr_zones - 1].start + zones[nr_zones - 1].len;
497 	}
498 
499 	if (nreported != zone_info->nr_zones) {
500 		btrfs_err_in_rcu(device->fs_info,
501 				 "inconsistent number of zones on %s (%u/%u)",
502 				 rcu_str_deref(device->name), nreported,
503 				 zone_info->nr_zones);
504 		ret = -EIO;
505 		goto out;
506 	}
507 
508 	if (max_active_zones) {
509 		if (nactive > max_active_zones) {
510 			btrfs_err_in_rcu(device->fs_info,
511 			"zoned: %u active zones on %s exceeds max_active_zones %u",
512 					 nactive, rcu_str_deref(device->name),
513 					 max_active_zones);
514 			ret = -EIO;
515 			goto out;
516 		}
517 		atomic_set(&zone_info->active_zones_left,
518 			   max_active_zones - nactive);
519 		set_bit(BTRFS_FS_ACTIVE_ZONE_TRACKING, &fs_info->flags);
520 	}
521 
522 	/* Validate superblock log */
523 	nr_zones = BTRFS_NR_SB_LOG_ZONES;
524 	for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
525 		u32 sb_zone;
526 		u64 sb_wp;
527 		int sb_pos = BTRFS_NR_SB_LOG_ZONES * i;
528 
529 		sb_zone = sb_zone_number(zone_info->zone_size_shift, i);
530 		if (sb_zone + 1 >= zone_info->nr_zones)
531 			continue;
532 
533 		ret = btrfs_get_dev_zones(device,
534 					  zone_start_physical(sb_zone, zone_info),
535 					  &zone_info->sb_zones[sb_pos],
536 					  &nr_zones);
537 		if (ret)
538 			goto out;
539 
540 		if (nr_zones != BTRFS_NR_SB_LOG_ZONES) {
541 			btrfs_err_in_rcu(device->fs_info,
542 	"zoned: failed to read super block log zone info at devid %llu zone %u",
543 					 device->devid, sb_zone);
544 			ret = -EUCLEAN;
545 			goto out;
546 		}
547 
548 		/*
549 		 * If zones[0] is conventional, always use the beginning of the
550 		 * zone to record superblock. No need to validate in that case.
551 		 */
552 		if (zone_info->sb_zones[BTRFS_NR_SB_LOG_ZONES * i].type ==
553 		    BLK_ZONE_TYPE_CONVENTIONAL)
554 			continue;
555 
556 		ret = sb_write_pointer(device->bdev,
557 				       &zone_info->sb_zones[sb_pos], &sb_wp);
558 		if (ret != -ENOENT && ret) {
559 			btrfs_err_in_rcu(device->fs_info,
560 			"zoned: super block log zone corrupted devid %llu zone %u",
561 					 device->devid, sb_zone);
562 			ret = -EUCLEAN;
563 			goto out;
564 		}
565 	}
566 
567 
568 	kvfree(zones);
569 
570 	if (bdev_is_zoned(bdev)) {
571 		model = "host-managed zoned";
572 		emulated = "";
573 	} else {
574 		model = "regular";
575 		emulated = "emulated ";
576 	}
577 
578 	btrfs_info_in_rcu(fs_info,
579 		"%s block device %s, %u %szones of %llu bytes",
580 		model, rcu_str_deref(device->name), zone_info->nr_zones,
581 		emulated, zone_info->zone_size);
582 
583 	return 0;
584 
585 out:
586 	kvfree(zones);
587 	btrfs_destroy_dev_zone_info(device);
588 	return ret;
589 }
590 
btrfs_destroy_dev_zone_info(struct btrfs_device * device)591 void btrfs_destroy_dev_zone_info(struct btrfs_device *device)
592 {
593 	struct btrfs_zoned_device_info *zone_info = device->zone_info;
594 
595 	if (!zone_info)
596 		return;
597 
598 	bitmap_free(zone_info->active_zones);
599 	bitmap_free(zone_info->seq_zones);
600 	bitmap_free(zone_info->empty_zones);
601 	vfree(zone_info->zone_cache);
602 	kfree(zone_info);
603 	device->zone_info = NULL;
604 }
605 
btrfs_clone_dev_zone_info(struct btrfs_device * orig_dev)606 struct btrfs_zoned_device_info *btrfs_clone_dev_zone_info(struct btrfs_device *orig_dev)
607 {
608 	struct btrfs_zoned_device_info *zone_info;
609 
610 	zone_info = kmemdup(orig_dev->zone_info, sizeof(*zone_info), GFP_KERNEL);
611 	if (!zone_info)
612 		return NULL;
613 
614 	zone_info->seq_zones = bitmap_zalloc(zone_info->nr_zones, GFP_KERNEL);
615 	if (!zone_info->seq_zones)
616 		goto out;
617 
618 	bitmap_copy(zone_info->seq_zones, orig_dev->zone_info->seq_zones,
619 		    zone_info->nr_zones);
620 
621 	zone_info->empty_zones = bitmap_zalloc(zone_info->nr_zones, GFP_KERNEL);
622 	if (!zone_info->empty_zones)
623 		goto out;
624 
625 	bitmap_copy(zone_info->empty_zones, orig_dev->zone_info->empty_zones,
626 		    zone_info->nr_zones);
627 
628 	zone_info->active_zones = bitmap_zalloc(zone_info->nr_zones, GFP_KERNEL);
629 	if (!zone_info->active_zones)
630 		goto out;
631 
632 	bitmap_copy(zone_info->active_zones, orig_dev->zone_info->active_zones,
633 		    zone_info->nr_zones);
634 	zone_info->zone_cache = NULL;
635 
636 	return zone_info;
637 
638 out:
639 	bitmap_free(zone_info->seq_zones);
640 	bitmap_free(zone_info->empty_zones);
641 	bitmap_free(zone_info->active_zones);
642 	kfree(zone_info);
643 	return NULL;
644 }
645 
btrfs_get_dev_zone(struct btrfs_device * device,u64 pos,struct blk_zone * zone)646 static int btrfs_get_dev_zone(struct btrfs_device *device, u64 pos, struct blk_zone *zone)
647 {
648 	unsigned int nr_zones = 1;
649 	int ret;
650 
651 	ret = btrfs_get_dev_zones(device, pos, zone, &nr_zones);
652 	if (ret != 0 || !nr_zones)
653 		return ret ? ret : -EIO;
654 
655 	return 0;
656 }
657 
btrfs_check_for_zoned_device(struct btrfs_fs_info * fs_info)658 static int btrfs_check_for_zoned_device(struct btrfs_fs_info *fs_info)
659 {
660 	struct btrfs_device *device;
661 
662 	list_for_each_entry(device, &fs_info->fs_devices->devices, dev_list) {
663 		if (device->bdev && bdev_is_zoned(device->bdev)) {
664 			btrfs_err(fs_info,
665 				"zoned: mode not enabled but zoned device found: %pg",
666 				device->bdev);
667 			return -EINVAL;
668 		}
669 	}
670 
671 	return 0;
672 }
673 
btrfs_check_zoned_mode(struct btrfs_fs_info * fs_info)674 int btrfs_check_zoned_mode(struct btrfs_fs_info *fs_info)
675 {
676 	struct queue_limits *lim = &fs_info->limits;
677 	struct btrfs_device *device;
678 	u64 zone_size = 0;
679 	int ret;
680 
681 	/*
682 	 * Host-Managed devices can't be used without the ZONED flag.  With the
683 	 * ZONED all devices can be used, using zone emulation if required.
684 	 */
685 	if (!btrfs_fs_incompat(fs_info, ZONED))
686 		return btrfs_check_for_zoned_device(fs_info);
687 
688 	blk_set_stacking_limits(lim);
689 
690 	list_for_each_entry(device, &fs_info->fs_devices->devices, dev_list) {
691 		struct btrfs_zoned_device_info *zone_info = device->zone_info;
692 
693 		if (!device->bdev)
694 			continue;
695 
696 		if (!zone_size) {
697 			zone_size = zone_info->zone_size;
698 		} else if (zone_info->zone_size != zone_size) {
699 			btrfs_err(fs_info,
700 		"zoned: unequal block device zone sizes: have %llu found %llu",
701 				  zone_info->zone_size, zone_size);
702 			return -EINVAL;
703 		}
704 
705 		/*
706 		 * With the zoned emulation, we can have non-zoned device on the
707 		 * zoned mode. In this case, we don't have a valid max zone
708 		 * append size.
709 		 */
710 		if (bdev_is_zoned(device->bdev)) {
711 			blk_stack_limits(lim,
712 					 &bdev_get_queue(device->bdev)->limits,
713 					 0);
714 		}
715 	}
716 
717 	/*
718 	 * stripe_size is always aligned to BTRFS_STRIPE_LEN in
719 	 * btrfs_create_chunk(). Since we want stripe_len == zone_size,
720 	 * check the alignment here.
721 	 */
722 	if (!IS_ALIGNED(zone_size, BTRFS_STRIPE_LEN)) {
723 		btrfs_err(fs_info,
724 			  "zoned: zone size %llu not aligned to stripe %u",
725 			  zone_size, BTRFS_STRIPE_LEN);
726 		return -EINVAL;
727 	}
728 
729 	if (btrfs_fs_incompat(fs_info, MIXED_GROUPS)) {
730 		btrfs_err(fs_info, "zoned: mixed block groups not supported");
731 		return -EINVAL;
732 	}
733 
734 	fs_info->zone_size = zone_size;
735 	/*
736 	 * Also limit max_zone_append_size by max_segments * PAGE_SIZE.
737 	 * Technically, we can have multiple pages per segment. But, since
738 	 * we add the pages one by one to a bio, and cannot increase the
739 	 * metadata reservation even if it increases the number of extents, it
740 	 * is safe to stick with the limit.
741 	 */
742 	fs_info->max_zone_append_size = ALIGN_DOWN(
743 		min3((u64)lim->max_zone_append_sectors << SECTOR_SHIFT,
744 		     (u64)lim->max_sectors << SECTOR_SHIFT,
745 		     (u64)lim->max_segments << PAGE_SHIFT),
746 		fs_info->sectorsize);
747 	fs_info->fs_devices->chunk_alloc_policy = BTRFS_CHUNK_ALLOC_ZONED;
748 	if (fs_info->max_zone_append_size < fs_info->max_extent_size)
749 		fs_info->max_extent_size = fs_info->max_zone_append_size;
750 
751 	/*
752 	 * Check mount options here, because we might change fs_info->zoned
753 	 * from fs_info->zone_size.
754 	 */
755 	ret = btrfs_check_mountopts_zoned(fs_info, &fs_info->mount_opt);
756 	if (ret)
757 		return ret;
758 
759 	btrfs_info(fs_info, "zoned mode enabled with zone size %llu", zone_size);
760 	return 0;
761 }
762 
btrfs_check_mountopts_zoned(const struct btrfs_fs_info * info,unsigned long long * mount_opt)763 int btrfs_check_mountopts_zoned(const struct btrfs_fs_info *info,
764 				unsigned long long *mount_opt)
765 {
766 	if (!btrfs_is_zoned(info))
767 		return 0;
768 
769 	/*
770 	 * Space cache writing is not COWed. Disable that to avoid write errors
771 	 * in sequential zones.
772 	 */
773 	if (btrfs_raw_test_opt(*mount_opt, SPACE_CACHE)) {
774 		btrfs_err(info, "zoned: space cache v1 is not supported");
775 		return -EINVAL;
776 	}
777 
778 	if (btrfs_raw_test_opt(*mount_opt, NODATACOW)) {
779 		btrfs_err(info, "zoned: NODATACOW not supported");
780 		return -EINVAL;
781 	}
782 
783 	if (btrfs_raw_test_opt(*mount_opt, DISCARD_ASYNC)) {
784 		btrfs_info(info,
785 			   "zoned: async discard ignored and disabled for zoned mode");
786 		btrfs_clear_opt(*mount_opt, DISCARD_ASYNC);
787 	}
788 
789 	return 0;
790 }
791 
sb_log_location(struct block_device * bdev,struct blk_zone * zones,int rw,u64 * bytenr_ret)792 static int sb_log_location(struct block_device *bdev, struct blk_zone *zones,
793 			   int rw, u64 *bytenr_ret)
794 {
795 	u64 wp;
796 	int ret;
797 
798 	if (zones[0].type == BLK_ZONE_TYPE_CONVENTIONAL) {
799 		*bytenr_ret = zones[0].start << SECTOR_SHIFT;
800 		return 0;
801 	}
802 
803 	ret = sb_write_pointer(bdev, zones, &wp);
804 	if (ret != -ENOENT && ret < 0)
805 		return ret;
806 
807 	if (rw == WRITE) {
808 		struct blk_zone *reset = NULL;
809 
810 		if (wp == zones[0].start << SECTOR_SHIFT)
811 			reset = &zones[0];
812 		else if (wp == zones[1].start << SECTOR_SHIFT)
813 			reset = &zones[1];
814 
815 		if (reset && reset->cond != BLK_ZONE_COND_EMPTY) {
816 			unsigned int nofs_flags;
817 
818 			ASSERT(sb_zone_is_full(reset));
819 
820 			nofs_flags = memalloc_nofs_save();
821 			ret = blkdev_zone_mgmt(bdev, REQ_OP_ZONE_RESET,
822 					       reset->start, reset->len);
823 			memalloc_nofs_restore(nofs_flags);
824 			if (ret)
825 				return ret;
826 
827 			reset->cond = BLK_ZONE_COND_EMPTY;
828 			reset->wp = reset->start;
829 		}
830 	} else if (ret != -ENOENT) {
831 		/*
832 		 * For READ, we want the previous one. Move write pointer to
833 		 * the end of a zone, if it is at the head of a zone.
834 		 */
835 		u64 zone_end = 0;
836 
837 		if (wp == zones[0].start << SECTOR_SHIFT)
838 			zone_end = zones[1].start + zones[1].capacity;
839 		else if (wp == zones[1].start << SECTOR_SHIFT)
840 			zone_end = zones[0].start + zones[0].capacity;
841 		if (zone_end)
842 			wp = ALIGN_DOWN(zone_end << SECTOR_SHIFT,
843 					BTRFS_SUPER_INFO_SIZE);
844 
845 		wp -= BTRFS_SUPER_INFO_SIZE;
846 	}
847 
848 	*bytenr_ret = wp;
849 	return 0;
850 
851 }
852 
btrfs_sb_log_location_bdev(struct block_device * bdev,int mirror,int rw,u64 * bytenr_ret)853 int btrfs_sb_log_location_bdev(struct block_device *bdev, int mirror, int rw,
854 			       u64 *bytenr_ret)
855 {
856 	struct blk_zone zones[BTRFS_NR_SB_LOG_ZONES];
857 	sector_t zone_sectors;
858 	u32 sb_zone;
859 	int ret;
860 	u8 zone_sectors_shift;
861 	sector_t nr_sectors;
862 	u32 nr_zones;
863 
864 	if (!bdev_is_zoned(bdev)) {
865 		*bytenr_ret = btrfs_sb_offset(mirror);
866 		return 0;
867 	}
868 
869 	ASSERT(rw == READ || rw == WRITE);
870 
871 	zone_sectors = bdev_zone_sectors(bdev);
872 	if (!is_power_of_2(zone_sectors))
873 		return -EINVAL;
874 	zone_sectors_shift = ilog2(zone_sectors);
875 	nr_sectors = bdev_nr_sectors(bdev);
876 	nr_zones = nr_sectors >> zone_sectors_shift;
877 
878 	sb_zone = sb_zone_number(zone_sectors_shift + SECTOR_SHIFT, mirror);
879 	if (sb_zone + 1 >= nr_zones)
880 		return -ENOENT;
881 
882 	ret = blkdev_report_zones(bdev, zone_start_sector(sb_zone, bdev),
883 				  BTRFS_NR_SB_LOG_ZONES, copy_zone_info_cb,
884 				  zones);
885 	if (ret < 0)
886 		return ret;
887 	if (ret != BTRFS_NR_SB_LOG_ZONES)
888 		return -EIO;
889 
890 	return sb_log_location(bdev, zones, rw, bytenr_ret);
891 }
892 
btrfs_sb_log_location(struct btrfs_device * device,int mirror,int rw,u64 * bytenr_ret)893 int btrfs_sb_log_location(struct btrfs_device *device, int mirror, int rw,
894 			  u64 *bytenr_ret)
895 {
896 	struct btrfs_zoned_device_info *zinfo = device->zone_info;
897 	u32 zone_num;
898 
899 	/*
900 	 * For a zoned filesystem on a non-zoned block device, use the same
901 	 * super block locations as regular filesystem. Doing so, the super
902 	 * block can always be retrieved and the zoned flag of the volume
903 	 * detected from the super block information.
904 	 */
905 	if (!bdev_is_zoned(device->bdev)) {
906 		*bytenr_ret = btrfs_sb_offset(mirror);
907 		return 0;
908 	}
909 
910 	zone_num = sb_zone_number(zinfo->zone_size_shift, mirror);
911 	if (zone_num + 1 >= zinfo->nr_zones)
912 		return -ENOENT;
913 
914 	return sb_log_location(device->bdev,
915 			       &zinfo->sb_zones[BTRFS_NR_SB_LOG_ZONES * mirror],
916 			       rw, bytenr_ret);
917 }
918 
is_sb_log_zone(struct btrfs_zoned_device_info * zinfo,int mirror)919 static inline bool is_sb_log_zone(struct btrfs_zoned_device_info *zinfo,
920 				  int mirror)
921 {
922 	u32 zone_num;
923 
924 	if (!zinfo)
925 		return false;
926 
927 	zone_num = sb_zone_number(zinfo->zone_size_shift, mirror);
928 	if (zone_num + 1 >= zinfo->nr_zones)
929 		return false;
930 
931 	if (!test_bit(zone_num, zinfo->seq_zones))
932 		return false;
933 
934 	return true;
935 }
936 
btrfs_advance_sb_log(struct btrfs_device * device,int mirror)937 int btrfs_advance_sb_log(struct btrfs_device *device, int mirror)
938 {
939 	struct btrfs_zoned_device_info *zinfo = device->zone_info;
940 	struct blk_zone *zone;
941 	int i;
942 
943 	if (!is_sb_log_zone(zinfo, mirror))
944 		return 0;
945 
946 	zone = &zinfo->sb_zones[BTRFS_NR_SB_LOG_ZONES * mirror];
947 	for (i = 0; i < BTRFS_NR_SB_LOG_ZONES; i++) {
948 		/* Advance the next zone */
949 		if (zone->cond == BLK_ZONE_COND_FULL) {
950 			zone++;
951 			continue;
952 		}
953 
954 		if (zone->cond == BLK_ZONE_COND_EMPTY)
955 			zone->cond = BLK_ZONE_COND_IMP_OPEN;
956 
957 		zone->wp += SUPER_INFO_SECTORS;
958 
959 		if (sb_zone_is_full(zone)) {
960 			/*
961 			 * No room left to write new superblock. Since
962 			 * superblock is written with REQ_SYNC, it is safe to
963 			 * finish the zone now.
964 			 *
965 			 * If the write pointer is exactly at the capacity,
966 			 * explicit ZONE_FINISH is not necessary.
967 			 */
968 			if (zone->wp != zone->start + zone->capacity) {
969 				unsigned int nofs_flags;
970 				int ret;
971 
972 				nofs_flags = memalloc_nofs_save();
973 				ret = blkdev_zone_mgmt(device->bdev,
974 						REQ_OP_ZONE_FINISH, zone->start,
975 						zone->len);
976 				memalloc_nofs_restore(nofs_flags);
977 				if (ret)
978 					return ret;
979 			}
980 
981 			zone->wp = zone->start + zone->len;
982 			zone->cond = BLK_ZONE_COND_FULL;
983 		}
984 		return 0;
985 	}
986 
987 	/* All the zones are FULL. Should not reach here. */
988 	ASSERT(0);
989 	return -EIO;
990 }
991 
btrfs_reset_sb_log_zones(struct block_device * bdev,int mirror)992 int btrfs_reset_sb_log_zones(struct block_device *bdev, int mirror)
993 {
994 	unsigned int nofs_flags;
995 	sector_t zone_sectors;
996 	sector_t nr_sectors;
997 	u8 zone_sectors_shift;
998 	u32 sb_zone;
999 	u32 nr_zones;
1000 	int ret;
1001 
1002 	zone_sectors = bdev_zone_sectors(bdev);
1003 	zone_sectors_shift = ilog2(zone_sectors);
1004 	nr_sectors = bdev_nr_sectors(bdev);
1005 	nr_zones = nr_sectors >> zone_sectors_shift;
1006 
1007 	sb_zone = sb_zone_number(zone_sectors_shift + SECTOR_SHIFT, mirror);
1008 	if (sb_zone + 1 >= nr_zones)
1009 		return -ENOENT;
1010 
1011 	nofs_flags = memalloc_nofs_save();
1012 	ret = blkdev_zone_mgmt(bdev, REQ_OP_ZONE_RESET,
1013 			       zone_start_sector(sb_zone, bdev),
1014 			       zone_sectors * BTRFS_NR_SB_LOG_ZONES);
1015 	memalloc_nofs_restore(nofs_flags);
1016 	return ret;
1017 }
1018 
1019 /*
1020  * Find allocatable zones within a given region.
1021  *
1022  * @device:	the device to allocate a region on
1023  * @hole_start: the position of the hole to allocate the region
1024  * @num_bytes:	size of wanted region
1025  * @hole_end:	the end of the hole
1026  * @return:	position of allocatable zones
1027  *
1028  * Allocatable region should not contain any superblock locations.
1029  */
btrfs_find_allocatable_zones(struct btrfs_device * device,u64 hole_start,u64 hole_end,u64 num_bytes)1030 u64 btrfs_find_allocatable_zones(struct btrfs_device *device, u64 hole_start,
1031 				 u64 hole_end, u64 num_bytes)
1032 {
1033 	struct btrfs_zoned_device_info *zinfo = device->zone_info;
1034 	const u8 shift = zinfo->zone_size_shift;
1035 	u64 nzones = num_bytes >> shift;
1036 	u64 pos = hole_start;
1037 	u64 begin, end;
1038 	bool have_sb;
1039 	int i;
1040 
1041 	ASSERT(IS_ALIGNED(hole_start, zinfo->zone_size));
1042 	ASSERT(IS_ALIGNED(num_bytes, zinfo->zone_size));
1043 
1044 	while (pos < hole_end) {
1045 		begin = pos >> shift;
1046 		end = begin + nzones;
1047 
1048 		if (end > zinfo->nr_zones)
1049 			return hole_end;
1050 
1051 		/* Check if zones in the region are all empty */
1052 		if (btrfs_dev_is_sequential(device, pos) &&
1053 		    !bitmap_test_range_all_set(zinfo->empty_zones, begin, nzones)) {
1054 			pos += zinfo->zone_size;
1055 			continue;
1056 		}
1057 
1058 		have_sb = false;
1059 		for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
1060 			u32 sb_zone;
1061 			u64 sb_pos;
1062 
1063 			sb_zone = sb_zone_number(shift, i);
1064 			if (!(end <= sb_zone ||
1065 			      sb_zone + BTRFS_NR_SB_LOG_ZONES <= begin)) {
1066 				have_sb = true;
1067 				pos = zone_start_physical(
1068 					sb_zone + BTRFS_NR_SB_LOG_ZONES, zinfo);
1069 				break;
1070 			}
1071 
1072 			/* We also need to exclude regular superblock positions */
1073 			sb_pos = btrfs_sb_offset(i);
1074 			if (!(pos + num_bytes <= sb_pos ||
1075 			      sb_pos + BTRFS_SUPER_INFO_SIZE <= pos)) {
1076 				have_sb = true;
1077 				pos = ALIGN(sb_pos + BTRFS_SUPER_INFO_SIZE,
1078 					    zinfo->zone_size);
1079 				break;
1080 			}
1081 		}
1082 		if (!have_sb)
1083 			break;
1084 	}
1085 
1086 	return pos;
1087 }
1088 
btrfs_dev_set_active_zone(struct btrfs_device * device,u64 pos)1089 static bool btrfs_dev_set_active_zone(struct btrfs_device *device, u64 pos)
1090 {
1091 	struct btrfs_zoned_device_info *zone_info = device->zone_info;
1092 	unsigned int zno = (pos >> zone_info->zone_size_shift);
1093 
1094 	/* We can use any number of zones */
1095 	if (zone_info->max_active_zones == 0)
1096 		return true;
1097 
1098 	if (!test_bit(zno, zone_info->active_zones)) {
1099 		/* Active zone left? */
1100 		if (atomic_dec_if_positive(&zone_info->active_zones_left) < 0)
1101 			return false;
1102 		if (test_and_set_bit(zno, zone_info->active_zones)) {
1103 			/* Someone already set the bit */
1104 			atomic_inc(&zone_info->active_zones_left);
1105 		}
1106 	}
1107 
1108 	return true;
1109 }
1110 
btrfs_dev_clear_active_zone(struct btrfs_device * device,u64 pos)1111 static void btrfs_dev_clear_active_zone(struct btrfs_device *device, u64 pos)
1112 {
1113 	struct btrfs_zoned_device_info *zone_info = device->zone_info;
1114 	unsigned int zno = (pos >> zone_info->zone_size_shift);
1115 
1116 	/* We can use any number of zones */
1117 	if (zone_info->max_active_zones == 0)
1118 		return;
1119 
1120 	if (test_and_clear_bit(zno, zone_info->active_zones))
1121 		atomic_inc(&zone_info->active_zones_left);
1122 }
1123 
btrfs_reset_device_zone(struct btrfs_device * device,u64 physical,u64 length,u64 * bytes)1124 int btrfs_reset_device_zone(struct btrfs_device *device, u64 physical,
1125 			    u64 length, u64 *bytes)
1126 {
1127 	unsigned int nofs_flags;
1128 	int ret;
1129 
1130 	*bytes = 0;
1131 	nofs_flags = memalloc_nofs_save();
1132 	ret = blkdev_zone_mgmt(device->bdev, REQ_OP_ZONE_RESET,
1133 			       physical >> SECTOR_SHIFT, length >> SECTOR_SHIFT);
1134 	memalloc_nofs_restore(nofs_flags);
1135 	if (ret)
1136 		return ret;
1137 
1138 	*bytes = length;
1139 	while (length) {
1140 		btrfs_dev_set_zone_empty(device, physical);
1141 		btrfs_dev_clear_active_zone(device, physical);
1142 		physical += device->zone_info->zone_size;
1143 		length -= device->zone_info->zone_size;
1144 	}
1145 
1146 	return 0;
1147 }
1148 
btrfs_ensure_empty_zones(struct btrfs_device * device,u64 start,u64 size)1149 int btrfs_ensure_empty_zones(struct btrfs_device *device, u64 start, u64 size)
1150 {
1151 	struct btrfs_zoned_device_info *zinfo = device->zone_info;
1152 	const u8 shift = zinfo->zone_size_shift;
1153 	unsigned long begin = start >> shift;
1154 	unsigned long nbits = size >> shift;
1155 	u64 pos;
1156 	int ret;
1157 
1158 	ASSERT(IS_ALIGNED(start, zinfo->zone_size));
1159 	ASSERT(IS_ALIGNED(size, zinfo->zone_size));
1160 
1161 	if (begin + nbits > zinfo->nr_zones)
1162 		return -ERANGE;
1163 
1164 	/* All the zones are conventional */
1165 	if (bitmap_test_range_all_zero(zinfo->seq_zones, begin, nbits))
1166 		return 0;
1167 
1168 	/* All the zones are sequential and empty */
1169 	if (bitmap_test_range_all_set(zinfo->seq_zones, begin, nbits) &&
1170 	    bitmap_test_range_all_set(zinfo->empty_zones, begin, nbits))
1171 		return 0;
1172 
1173 	for (pos = start; pos < start + size; pos += zinfo->zone_size) {
1174 		u64 reset_bytes;
1175 
1176 		if (!btrfs_dev_is_sequential(device, pos) ||
1177 		    btrfs_dev_is_empty_zone(device, pos))
1178 			continue;
1179 
1180 		/* Free regions should be empty */
1181 		btrfs_warn_in_rcu(
1182 			device->fs_info,
1183 		"zoned: resetting device %s (devid %llu) zone %llu for allocation",
1184 			rcu_str_deref(device->name), device->devid, pos >> shift);
1185 		WARN_ON_ONCE(1);
1186 
1187 		ret = btrfs_reset_device_zone(device, pos, zinfo->zone_size,
1188 					      &reset_bytes);
1189 		if (ret)
1190 			return ret;
1191 	}
1192 
1193 	return 0;
1194 }
1195 
1196 /*
1197  * Calculate an allocation pointer from the extent allocation information
1198  * for a block group consist of conventional zones. It is pointed to the
1199  * end of the highest addressed extent in the block group as an allocation
1200  * offset.
1201  */
calculate_alloc_pointer(struct btrfs_block_group * cache,u64 * offset_ret,bool new)1202 static int calculate_alloc_pointer(struct btrfs_block_group *cache,
1203 				   u64 *offset_ret, bool new)
1204 {
1205 	struct btrfs_fs_info *fs_info = cache->fs_info;
1206 	struct btrfs_root *root;
1207 	BTRFS_PATH_AUTO_FREE(path);
1208 	struct btrfs_key key;
1209 	struct btrfs_key found_key;
1210 	int ret;
1211 	u64 length;
1212 
1213 	/*
1214 	 * Avoid  tree lookups for a new block group, there's no use for it.
1215 	 * It must always be 0.
1216 	 *
1217 	 * Also, we have a lock chain of extent buffer lock -> chunk mutex.
1218 	 * For new a block group, this function is called from
1219 	 * btrfs_make_block_group() which is already taking the chunk mutex.
1220 	 * Thus, we cannot call calculate_alloc_pointer() which takes extent
1221 	 * buffer locks to avoid deadlock.
1222 	 */
1223 	if (new) {
1224 		*offset_ret = 0;
1225 		return 0;
1226 	}
1227 
1228 	path = btrfs_alloc_path();
1229 	if (!path)
1230 		return -ENOMEM;
1231 
1232 	key.objectid = cache->start + cache->length;
1233 	key.type = 0;
1234 	key.offset = 0;
1235 
1236 	root = btrfs_extent_root(fs_info, key.objectid);
1237 	ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1238 	/* We should not find the exact match */
1239 	if (!ret)
1240 		ret = -EUCLEAN;
1241 	if (ret < 0)
1242 		return ret;
1243 
1244 	ret = btrfs_previous_extent_item(root, path, cache->start);
1245 	if (ret) {
1246 		if (ret == 1) {
1247 			ret = 0;
1248 			*offset_ret = 0;
1249 		}
1250 		return ret;
1251 	}
1252 
1253 	btrfs_item_key_to_cpu(path->nodes[0], &found_key, path->slots[0]);
1254 
1255 	if (found_key.type == BTRFS_EXTENT_ITEM_KEY)
1256 		length = found_key.offset;
1257 	else
1258 		length = fs_info->nodesize;
1259 
1260 	if (!(found_key.objectid >= cache->start &&
1261 	       found_key.objectid + length <= cache->start + cache->length)) {
1262 		return -EUCLEAN;
1263 	}
1264 	*offset_ret = found_key.objectid + length - cache->start;
1265 	return 0;
1266 }
1267 
1268 struct zone_info {
1269 	u64 physical;
1270 	u64 capacity;
1271 	u64 alloc_offset;
1272 };
1273 
btrfs_load_zone_info(struct btrfs_fs_info * fs_info,int zone_idx,struct zone_info * info,unsigned long * active,struct btrfs_chunk_map * map)1274 static int btrfs_load_zone_info(struct btrfs_fs_info *fs_info, int zone_idx,
1275 				struct zone_info *info, unsigned long *active,
1276 				struct btrfs_chunk_map *map)
1277 {
1278 	struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
1279 	struct btrfs_device *device;
1280 	int dev_replace_is_ongoing = 0;
1281 	unsigned int nofs_flag;
1282 	struct blk_zone zone;
1283 	int ret;
1284 
1285 	info->physical = map->stripes[zone_idx].physical;
1286 
1287 	down_read(&dev_replace->rwsem);
1288 	device = map->stripes[zone_idx].dev;
1289 
1290 	if (!device->bdev) {
1291 		up_read(&dev_replace->rwsem);
1292 		info->alloc_offset = WP_MISSING_DEV;
1293 		return 0;
1294 	}
1295 
1296 	/* Consider a zone as active if we can allow any number of active zones. */
1297 	if (!device->zone_info->max_active_zones)
1298 		__set_bit(zone_idx, active);
1299 
1300 	if (!btrfs_dev_is_sequential(device, info->physical)) {
1301 		up_read(&dev_replace->rwsem);
1302 		info->alloc_offset = WP_CONVENTIONAL;
1303 		return 0;
1304 	}
1305 
1306 	/* This zone will be used for allocation, so mark this zone non-empty. */
1307 	btrfs_dev_clear_zone_empty(device, info->physical);
1308 
1309 	dev_replace_is_ongoing = btrfs_dev_replace_is_ongoing(dev_replace);
1310 	if (dev_replace_is_ongoing && dev_replace->tgtdev != NULL)
1311 		btrfs_dev_clear_zone_empty(dev_replace->tgtdev, info->physical);
1312 
1313 	/*
1314 	 * The group is mapped to a sequential zone. Get the zone write pointer
1315 	 * to determine the allocation offset within the zone.
1316 	 */
1317 	WARN_ON(!IS_ALIGNED(info->physical, fs_info->zone_size));
1318 	nofs_flag = memalloc_nofs_save();
1319 	ret = btrfs_get_dev_zone(device, info->physical, &zone);
1320 	memalloc_nofs_restore(nofs_flag);
1321 	if (ret) {
1322 		up_read(&dev_replace->rwsem);
1323 		if (ret != -EIO && ret != -EOPNOTSUPP)
1324 			return ret;
1325 		info->alloc_offset = WP_MISSING_DEV;
1326 		return 0;
1327 	}
1328 
1329 	if (zone.type == BLK_ZONE_TYPE_CONVENTIONAL) {
1330 		btrfs_err_in_rcu(fs_info,
1331 		"zoned: unexpected conventional zone %llu on device %s (devid %llu)",
1332 			zone.start << SECTOR_SHIFT, rcu_str_deref(device->name),
1333 			device->devid);
1334 		up_read(&dev_replace->rwsem);
1335 		return -EIO;
1336 	}
1337 
1338 	info->capacity = (zone.capacity << SECTOR_SHIFT);
1339 
1340 	switch (zone.cond) {
1341 	case BLK_ZONE_COND_OFFLINE:
1342 	case BLK_ZONE_COND_READONLY:
1343 		btrfs_err_in_rcu(fs_info,
1344 		"zoned: offline/readonly zone %llu on device %s (devid %llu)",
1345 			  (info->physical >> device->zone_info->zone_size_shift),
1346 			  rcu_str_deref(device->name), device->devid);
1347 		info->alloc_offset = WP_MISSING_DEV;
1348 		break;
1349 	case BLK_ZONE_COND_EMPTY:
1350 		info->alloc_offset = 0;
1351 		break;
1352 	case BLK_ZONE_COND_FULL:
1353 		info->alloc_offset = info->capacity;
1354 		break;
1355 	default:
1356 		/* Partially used zone. */
1357 		info->alloc_offset = ((zone.wp - zone.start) << SECTOR_SHIFT);
1358 		__set_bit(zone_idx, active);
1359 		break;
1360 	}
1361 
1362 	up_read(&dev_replace->rwsem);
1363 
1364 	return 0;
1365 }
1366 
btrfs_load_block_group_single(struct btrfs_block_group * bg,struct zone_info * info,unsigned long * active)1367 static int btrfs_load_block_group_single(struct btrfs_block_group *bg,
1368 					 struct zone_info *info,
1369 					 unsigned long *active)
1370 {
1371 	if (info->alloc_offset == WP_MISSING_DEV) {
1372 		btrfs_err(bg->fs_info,
1373 			"zoned: cannot recover write pointer for zone %llu",
1374 			info->physical);
1375 		return -EIO;
1376 	}
1377 
1378 	bg->alloc_offset = info->alloc_offset;
1379 	bg->zone_capacity = info->capacity;
1380 	if (test_bit(0, active))
1381 		set_bit(BLOCK_GROUP_FLAG_ZONE_IS_ACTIVE, &bg->runtime_flags);
1382 	return 0;
1383 }
1384 
btrfs_load_block_group_dup(struct btrfs_block_group * bg,struct btrfs_chunk_map * map,struct zone_info * zone_info,unsigned long * active)1385 static int btrfs_load_block_group_dup(struct btrfs_block_group *bg,
1386 				      struct btrfs_chunk_map *map,
1387 				      struct zone_info *zone_info,
1388 				      unsigned long *active)
1389 {
1390 	struct btrfs_fs_info *fs_info = bg->fs_info;
1391 
1392 	if ((map->type & BTRFS_BLOCK_GROUP_DATA) && !fs_info->stripe_root) {
1393 		btrfs_err(fs_info, "zoned: data DUP profile needs raid-stripe-tree");
1394 		return -EINVAL;
1395 	}
1396 
1397 	bg->zone_capacity = min_not_zero(zone_info[0].capacity, zone_info[1].capacity);
1398 
1399 	if (zone_info[0].alloc_offset == WP_MISSING_DEV) {
1400 		btrfs_err(bg->fs_info,
1401 			  "zoned: cannot recover write pointer for zone %llu",
1402 			  zone_info[0].physical);
1403 		return -EIO;
1404 	}
1405 	if (zone_info[1].alloc_offset == WP_MISSING_DEV) {
1406 		btrfs_err(bg->fs_info,
1407 			  "zoned: cannot recover write pointer for zone %llu",
1408 			  zone_info[1].physical);
1409 		return -EIO;
1410 	}
1411 	if (zone_info[0].alloc_offset != zone_info[1].alloc_offset) {
1412 		btrfs_err(bg->fs_info,
1413 			  "zoned: write pointer offset mismatch of zones in DUP profile");
1414 		return -EIO;
1415 	}
1416 
1417 	if (test_bit(0, active) != test_bit(1, active)) {
1418 		if (!btrfs_zone_activate(bg))
1419 			return -EIO;
1420 	} else if (test_bit(0, active)) {
1421 		set_bit(BLOCK_GROUP_FLAG_ZONE_IS_ACTIVE, &bg->runtime_flags);
1422 	}
1423 
1424 	bg->alloc_offset = zone_info[0].alloc_offset;
1425 	return 0;
1426 }
1427 
btrfs_load_block_group_raid1(struct btrfs_block_group * bg,struct btrfs_chunk_map * map,struct zone_info * zone_info,unsigned long * active)1428 static int btrfs_load_block_group_raid1(struct btrfs_block_group *bg,
1429 					struct btrfs_chunk_map *map,
1430 					struct zone_info *zone_info,
1431 					unsigned long *active)
1432 {
1433 	struct btrfs_fs_info *fs_info = bg->fs_info;
1434 	int i;
1435 
1436 	if ((map->type & BTRFS_BLOCK_GROUP_DATA) && !fs_info->stripe_root) {
1437 		btrfs_err(fs_info, "zoned: data %s needs raid-stripe-tree",
1438 			  btrfs_bg_type_to_raid_name(map->type));
1439 		return -EINVAL;
1440 	}
1441 
1442 	/* In case a device is missing we have a cap of 0, so don't use it. */
1443 	bg->zone_capacity = min_not_zero(zone_info[0].capacity, zone_info[1].capacity);
1444 
1445 	for (i = 0; i < map->num_stripes; i++) {
1446 		if (zone_info[i].alloc_offset == WP_MISSING_DEV ||
1447 		    zone_info[i].alloc_offset == WP_CONVENTIONAL)
1448 			continue;
1449 
1450 		if ((zone_info[0].alloc_offset != zone_info[i].alloc_offset) &&
1451 		    !btrfs_test_opt(fs_info, DEGRADED)) {
1452 			btrfs_err(fs_info,
1453 			"zoned: write pointer offset mismatch of zones in %s profile",
1454 				  btrfs_bg_type_to_raid_name(map->type));
1455 			return -EIO;
1456 		}
1457 		if (test_bit(0, active) != test_bit(i, active)) {
1458 			if (!btrfs_test_opt(fs_info, DEGRADED) &&
1459 			    !btrfs_zone_activate(bg)) {
1460 				return -EIO;
1461 			}
1462 		} else {
1463 			if (test_bit(0, active))
1464 				set_bit(BLOCK_GROUP_FLAG_ZONE_IS_ACTIVE, &bg->runtime_flags);
1465 		}
1466 	}
1467 
1468 	if (zone_info[0].alloc_offset != WP_MISSING_DEV)
1469 		bg->alloc_offset = zone_info[0].alloc_offset;
1470 	else
1471 		bg->alloc_offset = zone_info[i - 1].alloc_offset;
1472 
1473 	return 0;
1474 }
1475 
btrfs_load_block_group_raid0(struct btrfs_block_group * bg,struct btrfs_chunk_map * map,struct zone_info * zone_info,unsigned long * active)1476 static int btrfs_load_block_group_raid0(struct btrfs_block_group *bg,
1477 					struct btrfs_chunk_map *map,
1478 					struct zone_info *zone_info,
1479 					unsigned long *active)
1480 {
1481 	struct btrfs_fs_info *fs_info = bg->fs_info;
1482 
1483 	if ((map->type & BTRFS_BLOCK_GROUP_DATA) && !fs_info->stripe_root) {
1484 		btrfs_err(fs_info, "zoned: data %s needs raid-stripe-tree",
1485 			  btrfs_bg_type_to_raid_name(map->type));
1486 		return -EINVAL;
1487 	}
1488 
1489 	for (int i = 0; i < map->num_stripes; i++) {
1490 		if (zone_info[i].alloc_offset == WP_MISSING_DEV ||
1491 		    zone_info[i].alloc_offset == WP_CONVENTIONAL)
1492 			continue;
1493 
1494 		if (test_bit(0, active) != test_bit(i, active)) {
1495 			if (!btrfs_zone_activate(bg))
1496 				return -EIO;
1497 		} else {
1498 			if (test_bit(0, active))
1499 				set_bit(BLOCK_GROUP_FLAG_ZONE_IS_ACTIVE, &bg->runtime_flags);
1500 		}
1501 		bg->zone_capacity += zone_info[i].capacity;
1502 		bg->alloc_offset += zone_info[i].alloc_offset;
1503 	}
1504 
1505 	return 0;
1506 }
1507 
btrfs_load_block_group_raid10(struct btrfs_block_group * bg,struct btrfs_chunk_map * map,struct zone_info * zone_info,unsigned long * active)1508 static int btrfs_load_block_group_raid10(struct btrfs_block_group *bg,
1509 					 struct btrfs_chunk_map *map,
1510 					 struct zone_info *zone_info,
1511 					 unsigned long *active)
1512 {
1513 	struct btrfs_fs_info *fs_info = bg->fs_info;
1514 
1515 	if ((map->type & BTRFS_BLOCK_GROUP_DATA) && !fs_info->stripe_root) {
1516 		btrfs_err(fs_info, "zoned: data %s needs raid-stripe-tree",
1517 			  btrfs_bg_type_to_raid_name(map->type));
1518 		return -EINVAL;
1519 	}
1520 
1521 	for (int i = 0; i < map->num_stripes; i++) {
1522 		if (zone_info[i].alloc_offset == WP_MISSING_DEV ||
1523 		    zone_info[i].alloc_offset == WP_CONVENTIONAL)
1524 			continue;
1525 
1526 		if (test_bit(0, active) != test_bit(i, active)) {
1527 			if (!btrfs_zone_activate(bg))
1528 				return -EIO;
1529 		} else {
1530 			if (test_bit(0, active))
1531 				set_bit(BLOCK_GROUP_FLAG_ZONE_IS_ACTIVE, &bg->runtime_flags);
1532 		}
1533 
1534 		if ((i % map->sub_stripes) == 0) {
1535 			bg->zone_capacity += zone_info[i].capacity;
1536 			bg->alloc_offset += zone_info[i].alloc_offset;
1537 		}
1538 	}
1539 
1540 	return 0;
1541 }
1542 
btrfs_load_block_group_zone_info(struct btrfs_block_group * cache,bool new)1543 int btrfs_load_block_group_zone_info(struct btrfs_block_group *cache, bool new)
1544 {
1545 	struct btrfs_fs_info *fs_info = cache->fs_info;
1546 	struct btrfs_chunk_map *map;
1547 	u64 logical = cache->start;
1548 	u64 length = cache->length;
1549 	struct zone_info *zone_info = NULL;
1550 	int ret;
1551 	int i;
1552 	unsigned long *active = NULL;
1553 	u64 last_alloc = 0;
1554 	u32 num_sequential = 0, num_conventional = 0;
1555 	u64 profile;
1556 
1557 	if (!btrfs_is_zoned(fs_info))
1558 		return 0;
1559 
1560 	/* Sanity check */
1561 	if (!IS_ALIGNED(length, fs_info->zone_size)) {
1562 		btrfs_err(fs_info,
1563 		"zoned: block group %llu len %llu unaligned to zone size %llu",
1564 			  logical, length, fs_info->zone_size);
1565 		return -EIO;
1566 	}
1567 
1568 	map = btrfs_find_chunk_map(fs_info, logical, length);
1569 	if (!map)
1570 		return -EINVAL;
1571 
1572 	cache->physical_map = map;
1573 
1574 	zone_info = kcalloc(map->num_stripes, sizeof(*zone_info), GFP_NOFS);
1575 	if (!zone_info) {
1576 		ret = -ENOMEM;
1577 		goto out;
1578 	}
1579 
1580 	active = bitmap_zalloc(map->num_stripes, GFP_NOFS);
1581 	if (!active) {
1582 		ret = -ENOMEM;
1583 		goto out;
1584 	}
1585 
1586 	for (i = 0; i < map->num_stripes; i++) {
1587 		ret = btrfs_load_zone_info(fs_info, i, &zone_info[i], active, map);
1588 		if (ret)
1589 			goto out;
1590 
1591 		if (zone_info[i].alloc_offset == WP_CONVENTIONAL)
1592 			num_conventional++;
1593 		else
1594 			num_sequential++;
1595 	}
1596 
1597 	if (num_sequential > 0)
1598 		set_bit(BLOCK_GROUP_FLAG_SEQUENTIAL_ZONE, &cache->runtime_flags);
1599 
1600 	if (num_conventional > 0) {
1601 		/* Zone capacity is always zone size in emulation */
1602 		cache->zone_capacity = cache->length;
1603 		ret = calculate_alloc_pointer(cache, &last_alloc, new);
1604 		if (ret) {
1605 			btrfs_err(fs_info,
1606 			"zoned: failed to determine allocation offset of bg %llu",
1607 				  cache->start);
1608 			goto out;
1609 		} else if (map->num_stripes == num_conventional) {
1610 			cache->alloc_offset = last_alloc;
1611 			set_bit(BLOCK_GROUP_FLAG_ZONE_IS_ACTIVE, &cache->runtime_flags);
1612 			goto out;
1613 		}
1614 	}
1615 
1616 	profile = map->type & BTRFS_BLOCK_GROUP_PROFILE_MASK;
1617 	switch (profile) {
1618 	case 0: /* single */
1619 		ret = btrfs_load_block_group_single(cache, &zone_info[0], active);
1620 		break;
1621 	case BTRFS_BLOCK_GROUP_DUP:
1622 		ret = btrfs_load_block_group_dup(cache, map, zone_info, active);
1623 		break;
1624 	case BTRFS_BLOCK_GROUP_RAID1:
1625 	case BTRFS_BLOCK_GROUP_RAID1C3:
1626 	case BTRFS_BLOCK_GROUP_RAID1C4:
1627 		ret = btrfs_load_block_group_raid1(cache, map, zone_info, active);
1628 		break;
1629 	case BTRFS_BLOCK_GROUP_RAID0:
1630 		ret = btrfs_load_block_group_raid0(cache, map, zone_info, active);
1631 		break;
1632 	case BTRFS_BLOCK_GROUP_RAID10:
1633 		ret = btrfs_load_block_group_raid10(cache, map, zone_info, active);
1634 		break;
1635 	case BTRFS_BLOCK_GROUP_RAID5:
1636 	case BTRFS_BLOCK_GROUP_RAID6:
1637 	default:
1638 		btrfs_err(fs_info, "zoned: profile %s not yet supported",
1639 			  btrfs_bg_type_to_raid_name(map->type));
1640 		ret = -EINVAL;
1641 		goto out;
1642 	}
1643 
1644 	if (ret == -EIO && profile != 0 && profile != BTRFS_BLOCK_GROUP_RAID0 &&
1645 	    profile != BTRFS_BLOCK_GROUP_RAID10) {
1646 		/*
1647 		 * Detected broken write pointer.  Make this block group
1648 		 * unallocatable by setting the allocation pointer at the end of
1649 		 * allocatable region. Relocating this block group will fix the
1650 		 * mismatch.
1651 		 *
1652 		 * Currently, we cannot handle RAID0 or RAID10 case like this
1653 		 * because we don't have a proper zone_capacity value. But,
1654 		 * reading from this block group won't work anyway by a missing
1655 		 * stripe.
1656 		 */
1657 		cache->alloc_offset = cache->zone_capacity;
1658 		ret = 0;
1659 	}
1660 
1661 out:
1662 	/* Reject non SINGLE data profiles without RST */
1663 	if ((map->type & BTRFS_BLOCK_GROUP_DATA) &&
1664 	    (map->type & BTRFS_BLOCK_GROUP_PROFILE_MASK) &&
1665 	    !fs_info->stripe_root) {
1666 		btrfs_err(fs_info, "zoned: data %s needs raid-stripe-tree",
1667 			  btrfs_bg_type_to_raid_name(map->type));
1668 		return -EINVAL;
1669 	}
1670 
1671 	if (cache->alloc_offset > cache->zone_capacity) {
1672 		btrfs_err(fs_info,
1673 "zoned: invalid write pointer %llu (larger than zone capacity %llu) in block group %llu",
1674 			  cache->alloc_offset, cache->zone_capacity,
1675 			  cache->start);
1676 		ret = -EIO;
1677 	}
1678 
1679 	/* An extent is allocated after the write pointer */
1680 	if (!ret && num_conventional && last_alloc > cache->alloc_offset) {
1681 		btrfs_err(fs_info,
1682 			  "zoned: got wrong write pointer in BG %llu: %llu > %llu",
1683 			  logical, last_alloc, cache->alloc_offset);
1684 		ret = -EIO;
1685 	}
1686 
1687 	if (!ret) {
1688 		cache->meta_write_pointer = cache->alloc_offset + cache->start;
1689 		if (test_bit(BLOCK_GROUP_FLAG_ZONE_IS_ACTIVE, &cache->runtime_flags)) {
1690 			btrfs_get_block_group(cache);
1691 			spin_lock(&fs_info->zone_active_bgs_lock);
1692 			list_add_tail(&cache->active_bg_list,
1693 				      &fs_info->zone_active_bgs);
1694 			spin_unlock(&fs_info->zone_active_bgs_lock);
1695 		}
1696 	} else {
1697 		btrfs_free_chunk_map(cache->physical_map);
1698 		cache->physical_map = NULL;
1699 	}
1700 	bitmap_free(active);
1701 	kfree(zone_info);
1702 
1703 	return ret;
1704 }
1705 
btrfs_calc_zone_unusable(struct btrfs_block_group * cache)1706 void btrfs_calc_zone_unusable(struct btrfs_block_group *cache)
1707 {
1708 	u64 unusable, free;
1709 
1710 	if (!btrfs_is_zoned(cache->fs_info))
1711 		return;
1712 
1713 	WARN_ON(cache->bytes_super != 0);
1714 	unusable = (cache->alloc_offset - cache->used) +
1715 		   (cache->length - cache->zone_capacity);
1716 	free = cache->zone_capacity - cache->alloc_offset;
1717 
1718 	/* We only need ->free_space in ALLOC_SEQ block groups */
1719 	cache->cached = BTRFS_CACHE_FINISHED;
1720 	cache->free_space_ctl->free_space = free;
1721 	cache->zone_unusable = unusable;
1722 }
1723 
btrfs_use_zone_append(struct btrfs_bio * bbio)1724 bool btrfs_use_zone_append(struct btrfs_bio *bbio)
1725 {
1726 	u64 start = (bbio->bio.bi_iter.bi_sector << SECTOR_SHIFT);
1727 	struct btrfs_inode *inode = bbio->inode;
1728 	struct btrfs_fs_info *fs_info = bbio->fs_info;
1729 	struct btrfs_block_group *cache;
1730 	bool ret = false;
1731 
1732 	if (!btrfs_is_zoned(fs_info))
1733 		return false;
1734 
1735 	if (!inode || !is_data_inode(inode))
1736 		return false;
1737 
1738 	if (btrfs_op(&bbio->bio) != BTRFS_MAP_WRITE)
1739 		return false;
1740 
1741 	/*
1742 	 * Using REQ_OP_ZONE_APPNED for relocation can break assumptions on the
1743 	 * extent layout the relocation code has.
1744 	 * Furthermore we have set aside own block-group from which only the
1745 	 * relocation "process" can allocate and make sure only one process at a
1746 	 * time can add pages to an extent that gets relocated, so it's safe to
1747 	 * use regular REQ_OP_WRITE for this special case.
1748 	 */
1749 	if (btrfs_is_data_reloc_root(inode->root))
1750 		return false;
1751 
1752 	cache = btrfs_lookup_block_group(fs_info, start);
1753 	ASSERT(cache);
1754 	if (!cache)
1755 		return false;
1756 
1757 	ret = !!test_bit(BLOCK_GROUP_FLAG_SEQUENTIAL_ZONE, &cache->runtime_flags);
1758 	btrfs_put_block_group(cache);
1759 
1760 	return ret;
1761 }
1762 
btrfs_record_physical_zoned(struct btrfs_bio * bbio)1763 void btrfs_record_physical_zoned(struct btrfs_bio *bbio)
1764 {
1765 	const u64 physical = bbio->bio.bi_iter.bi_sector << SECTOR_SHIFT;
1766 	struct btrfs_ordered_sum *sum = bbio->sums;
1767 
1768 	if (physical < bbio->orig_physical)
1769 		sum->logical -= bbio->orig_physical - physical;
1770 	else
1771 		sum->logical += physical - bbio->orig_physical;
1772 }
1773 
btrfs_rewrite_logical_zoned(struct btrfs_ordered_extent * ordered,u64 logical)1774 static void btrfs_rewrite_logical_zoned(struct btrfs_ordered_extent *ordered,
1775 					u64 logical)
1776 {
1777 	struct extent_map_tree *em_tree = &ordered->inode->extent_tree;
1778 	struct extent_map *em;
1779 
1780 	ordered->disk_bytenr = logical;
1781 
1782 	write_lock(&em_tree->lock);
1783 	em = search_extent_mapping(em_tree, ordered->file_offset,
1784 				   ordered->num_bytes);
1785 	/* The em should be a new COW extent, thus it should not have an offset. */
1786 	ASSERT(em->offset == 0);
1787 	em->disk_bytenr = logical;
1788 	free_extent_map(em);
1789 	write_unlock(&em_tree->lock);
1790 }
1791 
btrfs_zoned_split_ordered(struct btrfs_ordered_extent * ordered,u64 logical,u64 len)1792 static bool btrfs_zoned_split_ordered(struct btrfs_ordered_extent *ordered,
1793 				      u64 logical, u64 len)
1794 {
1795 	struct btrfs_ordered_extent *new;
1796 
1797 	if (!test_bit(BTRFS_ORDERED_NOCOW, &ordered->flags) &&
1798 	    split_extent_map(ordered->inode, ordered->file_offset,
1799 			     ordered->num_bytes, len, logical))
1800 		return false;
1801 
1802 	new = btrfs_split_ordered_extent(ordered, len);
1803 	if (IS_ERR(new))
1804 		return false;
1805 	new->disk_bytenr = logical;
1806 	btrfs_finish_one_ordered(new);
1807 	return true;
1808 }
1809 
btrfs_finish_ordered_zoned(struct btrfs_ordered_extent * ordered)1810 void btrfs_finish_ordered_zoned(struct btrfs_ordered_extent *ordered)
1811 {
1812 	struct btrfs_inode *inode = ordered->inode;
1813 	struct btrfs_fs_info *fs_info = inode->root->fs_info;
1814 	struct btrfs_ordered_sum *sum;
1815 	u64 logical, len;
1816 
1817 	/*
1818 	 * Write to pre-allocated region is for the data relocation, and so
1819 	 * it should use WRITE operation. No split/rewrite are necessary.
1820 	 */
1821 	if (test_bit(BTRFS_ORDERED_PREALLOC, &ordered->flags))
1822 		return;
1823 
1824 	ASSERT(!list_empty(&ordered->list));
1825 	/* The ordered->list can be empty in the above pre-alloc case. */
1826 	sum = list_first_entry(&ordered->list, struct btrfs_ordered_sum, list);
1827 	logical = sum->logical;
1828 	len = sum->len;
1829 
1830 	while (len < ordered->disk_num_bytes) {
1831 		sum = list_next_entry(sum, list);
1832 		if (sum->logical == logical + len) {
1833 			len += sum->len;
1834 			continue;
1835 		}
1836 		if (!btrfs_zoned_split_ordered(ordered, logical, len)) {
1837 			set_bit(BTRFS_ORDERED_IOERR, &ordered->flags);
1838 			btrfs_err(fs_info, "failed to split ordered extent");
1839 			goto out;
1840 		}
1841 		logical = sum->logical;
1842 		len = sum->len;
1843 	}
1844 
1845 	if (ordered->disk_bytenr != logical)
1846 		btrfs_rewrite_logical_zoned(ordered, logical);
1847 
1848 out:
1849 	/*
1850 	 * If we end up here for nodatasum I/O, the btrfs_ordered_sum structures
1851 	 * were allocated by btrfs_alloc_dummy_sum only to record the logical
1852 	 * addresses and don't contain actual checksums.  We thus must free them
1853 	 * here so that we don't attempt to log the csums later.
1854 	 */
1855 	if ((inode->flags & BTRFS_INODE_NODATASUM) ||
1856 	    test_bit(BTRFS_FS_STATE_NO_DATA_CSUMS, &fs_info->fs_state)) {
1857 		while ((sum = list_first_entry_or_null(&ordered->list,
1858 						       typeof(*sum), list))) {
1859 			list_del(&sum->list);
1860 			kfree(sum);
1861 		}
1862 	}
1863 }
1864 
check_bg_is_active(struct btrfs_eb_write_context * ctx,struct btrfs_block_group ** active_bg)1865 static bool check_bg_is_active(struct btrfs_eb_write_context *ctx,
1866 			       struct btrfs_block_group **active_bg)
1867 {
1868 	const struct writeback_control *wbc = ctx->wbc;
1869 	struct btrfs_block_group *block_group = ctx->zoned_bg;
1870 	struct btrfs_fs_info *fs_info = block_group->fs_info;
1871 
1872 	if (test_bit(BLOCK_GROUP_FLAG_ZONE_IS_ACTIVE, &block_group->runtime_flags))
1873 		return true;
1874 
1875 	if (fs_info->treelog_bg == block_group->start) {
1876 		if (!btrfs_zone_activate(block_group)) {
1877 			int ret_fin = btrfs_zone_finish_one_bg(fs_info);
1878 
1879 			if (ret_fin != 1 || !btrfs_zone_activate(block_group))
1880 				return false;
1881 		}
1882 	} else if (*active_bg != block_group) {
1883 		struct btrfs_block_group *tgt = *active_bg;
1884 
1885 		/* zoned_meta_io_lock protects fs_info->active_{meta,system}_bg. */
1886 		lockdep_assert_held(&fs_info->zoned_meta_io_lock);
1887 
1888 		if (tgt) {
1889 			/*
1890 			 * If there is an unsent IO left in the allocated area,
1891 			 * we cannot wait for them as it may cause a deadlock.
1892 			 */
1893 			if (tgt->meta_write_pointer < tgt->start + tgt->alloc_offset) {
1894 				if (wbc->sync_mode == WB_SYNC_NONE ||
1895 				    (wbc->sync_mode == WB_SYNC_ALL && !wbc->for_sync))
1896 					return false;
1897 			}
1898 
1899 			/* Pivot active metadata/system block group. */
1900 			btrfs_zoned_meta_io_unlock(fs_info);
1901 			wait_eb_writebacks(tgt);
1902 			do_zone_finish(tgt, true);
1903 			btrfs_zoned_meta_io_lock(fs_info);
1904 			if (*active_bg == tgt) {
1905 				btrfs_put_block_group(tgt);
1906 				*active_bg = NULL;
1907 			}
1908 		}
1909 		if (!btrfs_zone_activate(block_group))
1910 			return false;
1911 		if (*active_bg != block_group) {
1912 			ASSERT(*active_bg == NULL);
1913 			*active_bg = block_group;
1914 			btrfs_get_block_group(block_group);
1915 		}
1916 	}
1917 
1918 	return true;
1919 }
1920 
1921 /*
1922  * Check if @ctx->eb is aligned to the write pointer.
1923  *
1924  * Return:
1925  *   0:        @ctx->eb is at the write pointer. You can write it.
1926  *   -EAGAIN:  There is a hole. The caller should handle the case.
1927  *   -EBUSY:   There is a hole, but the caller can just bail out.
1928  */
btrfs_check_meta_write_pointer(struct btrfs_fs_info * fs_info,struct btrfs_eb_write_context * ctx)1929 int btrfs_check_meta_write_pointer(struct btrfs_fs_info *fs_info,
1930 				   struct btrfs_eb_write_context *ctx)
1931 {
1932 	const struct writeback_control *wbc = ctx->wbc;
1933 	const struct extent_buffer *eb = ctx->eb;
1934 	struct btrfs_block_group *block_group = ctx->zoned_bg;
1935 
1936 	if (!btrfs_is_zoned(fs_info))
1937 		return 0;
1938 
1939 	if (block_group) {
1940 		if (block_group->start > eb->start ||
1941 		    block_group->start + block_group->length <= eb->start) {
1942 			btrfs_put_block_group(block_group);
1943 			block_group = NULL;
1944 			ctx->zoned_bg = NULL;
1945 		}
1946 	}
1947 
1948 	if (!block_group) {
1949 		block_group = btrfs_lookup_block_group(fs_info, eb->start);
1950 		if (!block_group)
1951 			return 0;
1952 		ctx->zoned_bg = block_group;
1953 	}
1954 
1955 	if (block_group->meta_write_pointer == eb->start) {
1956 		struct btrfs_block_group **tgt;
1957 
1958 		if (!test_bit(BTRFS_FS_ACTIVE_ZONE_TRACKING, &fs_info->flags))
1959 			return 0;
1960 
1961 		if (block_group->flags & BTRFS_BLOCK_GROUP_SYSTEM)
1962 			tgt = &fs_info->active_system_bg;
1963 		else
1964 			tgt = &fs_info->active_meta_bg;
1965 		if (check_bg_is_active(ctx, tgt))
1966 			return 0;
1967 	}
1968 
1969 	/*
1970 	 * Since we may release fs_info->zoned_meta_io_lock, someone can already
1971 	 * start writing this eb. In that case, we can just bail out.
1972 	 */
1973 	if (block_group->meta_write_pointer > eb->start)
1974 		return -EBUSY;
1975 
1976 	/* If for_sync, this hole will be filled with trasnsaction commit. */
1977 	if (wbc->sync_mode == WB_SYNC_ALL && !wbc->for_sync)
1978 		return -EAGAIN;
1979 	return -EBUSY;
1980 }
1981 
btrfs_zoned_issue_zeroout(struct btrfs_device * device,u64 physical,u64 length)1982 int btrfs_zoned_issue_zeroout(struct btrfs_device *device, u64 physical, u64 length)
1983 {
1984 	if (!btrfs_dev_is_sequential(device, physical))
1985 		return -EOPNOTSUPP;
1986 
1987 	return blkdev_issue_zeroout(device->bdev, physical >> SECTOR_SHIFT,
1988 				    length >> SECTOR_SHIFT, GFP_NOFS, 0);
1989 }
1990 
read_zone_info(struct btrfs_fs_info * fs_info,u64 logical,struct blk_zone * zone)1991 static int read_zone_info(struct btrfs_fs_info *fs_info, u64 logical,
1992 			  struct blk_zone *zone)
1993 {
1994 	struct btrfs_io_context *bioc = NULL;
1995 	u64 mapped_length = PAGE_SIZE;
1996 	unsigned int nofs_flag;
1997 	int nmirrors;
1998 	int i, ret;
1999 
2000 	ret = btrfs_map_block(fs_info, BTRFS_MAP_GET_READ_MIRRORS, logical,
2001 			      &mapped_length, &bioc, NULL, NULL);
2002 	if (ret || !bioc || mapped_length < PAGE_SIZE) {
2003 		ret = -EIO;
2004 		goto out_put_bioc;
2005 	}
2006 
2007 	if (bioc->map_type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
2008 		ret = -EINVAL;
2009 		goto out_put_bioc;
2010 	}
2011 
2012 	nofs_flag = memalloc_nofs_save();
2013 	nmirrors = (int)bioc->num_stripes;
2014 	for (i = 0; i < nmirrors; i++) {
2015 		u64 physical = bioc->stripes[i].physical;
2016 		struct btrfs_device *dev = bioc->stripes[i].dev;
2017 
2018 		/* Missing device */
2019 		if (!dev->bdev)
2020 			continue;
2021 
2022 		ret = btrfs_get_dev_zone(dev, physical, zone);
2023 		/* Failing device */
2024 		if (ret == -EIO || ret == -EOPNOTSUPP)
2025 			continue;
2026 		break;
2027 	}
2028 	memalloc_nofs_restore(nofs_flag);
2029 out_put_bioc:
2030 	btrfs_put_bioc(bioc);
2031 	return ret;
2032 }
2033 
2034 /*
2035  * Synchronize write pointer in a zone at @physical_start on @tgt_dev, by
2036  * filling zeros between @physical_pos to a write pointer of dev-replace
2037  * source device.
2038  */
btrfs_sync_zone_write_pointer(struct btrfs_device * tgt_dev,u64 logical,u64 physical_start,u64 physical_pos)2039 int btrfs_sync_zone_write_pointer(struct btrfs_device *tgt_dev, u64 logical,
2040 				    u64 physical_start, u64 physical_pos)
2041 {
2042 	struct btrfs_fs_info *fs_info = tgt_dev->fs_info;
2043 	struct blk_zone zone;
2044 	u64 length;
2045 	u64 wp;
2046 	int ret;
2047 
2048 	if (!btrfs_dev_is_sequential(tgt_dev, physical_pos))
2049 		return 0;
2050 
2051 	ret = read_zone_info(fs_info, logical, &zone);
2052 	if (ret)
2053 		return ret;
2054 
2055 	wp = physical_start + ((zone.wp - zone.start) << SECTOR_SHIFT);
2056 
2057 	if (physical_pos == wp)
2058 		return 0;
2059 
2060 	if (physical_pos > wp)
2061 		return -EUCLEAN;
2062 
2063 	length = wp - physical_pos;
2064 	return btrfs_zoned_issue_zeroout(tgt_dev, physical_pos, length);
2065 }
2066 
2067 /*
2068  * Activate block group and underlying device zones
2069  *
2070  * @block_group: the block group to activate
2071  *
2072  * Return: true on success, false otherwise
2073  */
btrfs_zone_activate(struct btrfs_block_group * block_group)2074 bool btrfs_zone_activate(struct btrfs_block_group *block_group)
2075 {
2076 	struct btrfs_fs_info *fs_info = block_group->fs_info;
2077 	struct btrfs_chunk_map *map;
2078 	struct btrfs_device *device;
2079 	u64 physical;
2080 	const bool is_data = (block_group->flags & BTRFS_BLOCK_GROUP_DATA);
2081 	bool ret;
2082 	int i;
2083 
2084 	if (!btrfs_is_zoned(block_group->fs_info))
2085 		return true;
2086 
2087 	map = block_group->physical_map;
2088 
2089 	spin_lock(&fs_info->zone_active_bgs_lock);
2090 	spin_lock(&block_group->lock);
2091 	if (test_bit(BLOCK_GROUP_FLAG_ZONE_IS_ACTIVE, &block_group->runtime_flags)) {
2092 		ret = true;
2093 		goto out_unlock;
2094 	}
2095 
2096 	/* No space left */
2097 	if (btrfs_zoned_bg_is_full(block_group)) {
2098 		ret = false;
2099 		goto out_unlock;
2100 	}
2101 
2102 	for (i = 0; i < map->num_stripes; i++) {
2103 		struct btrfs_zoned_device_info *zinfo;
2104 		int reserved = 0;
2105 
2106 		device = map->stripes[i].dev;
2107 		physical = map->stripes[i].physical;
2108 		zinfo = device->zone_info;
2109 
2110 		if (zinfo->max_active_zones == 0)
2111 			continue;
2112 
2113 		if (is_data)
2114 			reserved = zinfo->reserved_active_zones;
2115 		/*
2116 		 * For the data block group, leave active zones for one
2117 		 * metadata block group and one system block group.
2118 		 */
2119 		if (atomic_read(&zinfo->active_zones_left) <= reserved) {
2120 			ret = false;
2121 			goto out_unlock;
2122 		}
2123 
2124 		if (!btrfs_dev_set_active_zone(device, physical)) {
2125 			/* Cannot activate the zone */
2126 			ret = false;
2127 			goto out_unlock;
2128 		}
2129 		if (!is_data)
2130 			zinfo->reserved_active_zones--;
2131 	}
2132 
2133 	/* Successfully activated all the zones */
2134 	set_bit(BLOCK_GROUP_FLAG_ZONE_IS_ACTIVE, &block_group->runtime_flags);
2135 	spin_unlock(&block_group->lock);
2136 
2137 	/* For the active block group list */
2138 	btrfs_get_block_group(block_group);
2139 	list_add_tail(&block_group->active_bg_list, &fs_info->zone_active_bgs);
2140 	spin_unlock(&fs_info->zone_active_bgs_lock);
2141 
2142 	return true;
2143 
2144 out_unlock:
2145 	spin_unlock(&block_group->lock);
2146 	spin_unlock(&fs_info->zone_active_bgs_lock);
2147 	return ret;
2148 }
2149 
wait_eb_writebacks(struct btrfs_block_group * block_group)2150 static void wait_eb_writebacks(struct btrfs_block_group *block_group)
2151 {
2152 	struct btrfs_fs_info *fs_info = block_group->fs_info;
2153 	const u64 end = block_group->start + block_group->length;
2154 	struct radix_tree_iter iter;
2155 	struct extent_buffer *eb;
2156 	void __rcu **slot;
2157 
2158 	rcu_read_lock();
2159 	radix_tree_for_each_slot(slot, &fs_info->buffer_radix, &iter,
2160 				 block_group->start >> fs_info->sectorsize_bits) {
2161 		eb = radix_tree_deref_slot(slot);
2162 		if (!eb)
2163 			continue;
2164 		if (radix_tree_deref_retry(eb)) {
2165 			slot = radix_tree_iter_retry(&iter);
2166 			continue;
2167 		}
2168 
2169 		if (eb->start < block_group->start)
2170 			continue;
2171 		if (eb->start >= end)
2172 			break;
2173 
2174 		slot = radix_tree_iter_resume(slot, &iter);
2175 		rcu_read_unlock();
2176 		wait_on_extent_buffer_writeback(eb);
2177 		rcu_read_lock();
2178 	}
2179 	rcu_read_unlock();
2180 }
2181 
do_zone_finish(struct btrfs_block_group * block_group,bool fully_written)2182 static int do_zone_finish(struct btrfs_block_group *block_group, bool fully_written)
2183 {
2184 	struct btrfs_fs_info *fs_info = block_group->fs_info;
2185 	struct btrfs_chunk_map *map;
2186 	const bool is_metadata = (block_group->flags &
2187 			(BTRFS_BLOCK_GROUP_METADATA | BTRFS_BLOCK_GROUP_SYSTEM));
2188 	struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
2189 	int ret = 0;
2190 	int i;
2191 
2192 	spin_lock(&block_group->lock);
2193 	if (!test_bit(BLOCK_GROUP_FLAG_ZONE_IS_ACTIVE, &block_group->runtime_flags)) {
2194 		spin_unlock(&block_group->lock);
2195 		return 0;
2196 	}
2197 
2198 	/* Check if we have unwritten allocated space */
2199 	if (is_metadata &&
2200 	    block_group->start + block_group->alloc_offset > block_group->meta_write_pointer) {
2201 		spin_unlock(&block_group->lock);
2202 		return -EAGAIN;
2203 	}
2204 
2205 	/*
2206 	 * If we are sure that the block group is full (= no more room left for
2207 	 * new allocation) and the IO for the last usable block is completed, we
2208 	 * don't need to wait for the other IOs. This holds because we ensure
2209 	 * the sequential IO submissions using the ZONE_APPEND command for data
2210 	 * and block_group->meta_write_pointer for metadata.
2211 	 */
2212 	if (!fully_written) {
2213 		if (test_bit(BLOCK_GROUP_FLAG_ZONED_DATA_RELOC, &block_group->runtime_flags)) {
2214 			spin_unlock(&block_group->lock);
2215 			return -EAGAIN;
2216 		}
2217 		spin_unlock(&block_group->lock);
2218 
2219 		ret = btrfs_inc_block_group_ro(block_group, false);
2220 		if (ret)
2221 			return ret;
2222 
2223 		/* Ensure all writes in this block group finish */
2224 		btrfs_wait_block_group_reservations(block_group);
2225 		/* No need to wait for NOCOW writers. Zoned mode does not allow that */
2226 		btrfs_wait_ordered_roots(fs_info, U64_MAX, block_group);
2227 		/* Wait for extent buffers to be written. */
2228 		if (is_metadata)
2229 			wait_eb_writebacks(block_group);
2230 
2231 		spin_lock(&block_group->lock);
2232 
2233 		/*
2234 		 * Bail out if someone already deactivated the block group, or
2235 		 * allocated space is left in the block group.
2236 		 */
2237 		if (!test_bit(BLOCK_GROUP_FLAG_ZONE_IS_ACTIVE,
2238 			      &block_group->runtime_flags)) {
2239 			spin_unlock(&block_group->lock);
2240 			btrfs_dec_block_group_ro(block_group);
2241 			return 0;
2242 		}
2243 
2244 		if (block_group->reserved ||
2245 		    test_bit(BLOCK_GROUP_FLAG_ZONED_DATA_RELOC,
2246 			     &block_group->runtime_flags)) {
2247 			spin_unlock(&block_group->lock);
2248 			btrfs_dec_block_group_ro(block_group);
2249 			return -EAGAIN;
2250 		}
2251 	}
2252 
2253 	clear_bit(BLOCK_GROUP_FLAG_ZONE_IS_ACTIVE, &block_group->runtime_flags);
2254 	block_group->alloc_offset = block_group->zone_capacity;
2255 	if (block_group->flags & (BTRFS_BLOCK_GROUP_METADATA | BTRFS_BLOCK_GROUP_SYSTEM))
2256 		block_group->meta_write_pointer = block_group->start +
2257 						  block_group->zone_capacity;
2258 	block_group->free_space_ctl->free_space = 0;
2259 	btrfs_clear_treelog_bg(block_group);
2260 	btrfs_clear_data_reloc_bg(block_group);
2261 	spin_unlock(&block_group->lock);
2262 
2263 	down_read(&dev_replace->rwsem);
2264 	map = block_group->physical_map;
2265 	for (i = 0; i < map->num_stripes; i++) {
2266 		struct btrfs_device *device = map->stripes[i].dev;
2267 		const u64 physical = map->stripes[i].physical;
2268 		struct btrfs_zoned_device_info *zinfo = device->zone_info;
2269 		unsigned int nofs_flags;
2270 
2271 		if (zinfo->max_active_zones == 0)
2272 			continue;
2273 
2274 		nofs_flags = memalloc_nofs_save();
2275 		ret = blkdev_zone_mgmt(device->bdev, REQ_OP_ZONE_FINISH,
2276 				       physical >> SECTOR_SHIFT,
2277 				       zinfo->zone_size >> SECTOR_SHIFT);
2278 		memalloc_nofs_restore(nofs_flags);
2279 
2280 		if (ret) {
2281 			up_read(&dev_replace->rwsem);
2282 			return ret;
2283 		}
2284 
2285 		if (!(block_group->flags & BTRFS_BLOCK_GROUP_DATA))
2286 			zinfo->reserved_active_zones++;
2287 		btrfs_dev_clear_active_zone(device, physical);
2288 	}
2289 	up_read(&dev_replace->rwsem);
2290 
2291 	if (!fully_written)
2292 		btrfs_dec_block_group_ro(block_group);
2293 
2294 	spin_lock(&fs_info->zone_active_bgs_lock);
2295 	ASSERT(!list_empty(&block_group->active_bg_list));
2296 	list_del_init(&block_group->active_bg_list);
2297 	spin_unlock(&fs_info->zone_active_bgs_lock);
2298 
2299 	/* For active_bg_list */
2300 	btrfs_put_block_group(block_group);
2301 
2302 	clear_and_wake_up_bit(BTRFS_FS_NEED_ZONE_FINISH, &fs_info->flags);
2303 
2304 	return 0;
2305 }
2306 
btrfs_zone_finish(struct btrfs_block_group * block_group)2307 int btrfs_zone_finish(struct btrfs_block_group *block_group)
2308 {
2309 	if (!btrfs_is_zoned(block_group->fs_info))
2310 		return 0;
2311 
2312 	return do_zone_finish(block_group, false);
2313 }
2314 
btrfs_can_activate_zone(struct btrfs_fs_devices * fs_devices,u64 flags)2315 bool btrfs_can_activate_zone(struct btrfs_fs_devices *fs_devices, u64 flags)
2316 {
2317 	struct btrfs_fs_info *fs_info = fs_devices->fs_info;
2318 	struct btrfs_device *device;
2319 	bool ret = false;
2320 
2321 	if (!btrfs_is_zoned(fs_info))
2322 		return true;
2323 
2324 	/* Check if there is a device with active zones left */
2325 	mutex_lock(&fs_info->chunk_mutex);
2326 	spin_lock(&fs_info->zone_active_bgs_lock);
2327 	list_for_each_entry(device, &fs_devices->alloc_list, dev_alloc_list) {
2328 		struct btrfs_zoned_device_info *zinfo = device->zone_info;
2329 		int reserved = 0;
2330 
2331 		if (!device->bdev)
2332 			continue;
2333 
2334 		if (!zinfo->max_active_zones) {
2335 			ret = true;
2336 			break;
2337 		}
2338 
2339 		if (flags & BTRFS_BLOCK_GROUP_DATA)
2340 			reserved = zinfo->reserved_active_zones;
2341 
2342 		switch (flags & BTRFS_BLOCK_GROUP_PROFILE_MASK) {
2343 		case 0: /* single */
2344 			ret = (atomic_read(&zinfo->active_zones_left) >= (1 + reserved));
2345 			break;
2346 		case BTRFS_BLOCK_GROUP_DUP:
2347 			ret = (atomic_read(&zinfo->active_zones_left) >= (2 + reserved));
2348 			break;
2349 		}
2350 		if (ret)
2351 			break;
2352 	}
2353 	spin_unlock(&fs_info->zone_active_bgs_lock);
2354 	mutex_unlock(&fs_info->chunk_mutex);
2355 
2356 	if (!ret)
2357 		set_bit(BTRFS_FS_NEED_ZONE_FINISH, &fs_info->flags);
2358 
2359 	return ret;
2360 }
2361 
btrfs_zone_finish_endio(struct btrfs_fs_info * fs_info,u64 logical,u64 length)2362 void btrfs_zone_finish_endio(struct btrfs_fs_info *fs_info, u64 logical, u64 length)
2363 {
2364 	struct btrfs_block_group *block_group;
2365 	u64 min_alloc_bytes;
2366 
2367 	if (!btrfs_is_zoned(fs_info))
2368 		return;
2369 
2370 	block_group = btrfs_lookup_block_group(fs_info, logical);
2371 	ASSERT(block_group);
2372 
2373 	/* No MIXED_BG on zoned btrfs. */
2374 	if (block_group->flags & BTRFS_BLOCK_GROUP_DATA)
2375 		min_alloc_bytes = fs_info->sectorsize;
2376 	else
2377 		min_alloc_bytes = fs_info->nodesize;
2378 
2379 	/* Bail out if we can allocate more data from this block group. */
2380 	if (logical + length + min_alloc_bytes <=
2381 	    block_group->start + block_group->zone_capacity)
2382 		goto out;
2383 
2384 	do_zone_finish(block_group, true);
2385 
2386 out:
2387 	btrfs_put_block_group(block_group);
2388 }
2389 
btrfs_zone_finish_endio_workfn(struct work_struct * work)2390 static void btrfs_zone_finish_endio_workfn(struct work_struct *work)
2391 {
2392 	struct btrfs_block_group *bg =
2393 		container_of(work, struct btrfs_block_group, zone_finish_work);
2394 
2395 	wait_on_extent_buffer_writeback(bg->last_eb);
2396 	free_extent_buffer(bg->last_eb);
2397 	btrfs_zone_finish_endio(bg->fs_info, bg->start, bg->length);
2398 	btrfs_put_block_group(bg);
2399 }
2400 
btrfs_schedule_zone_finish_bg(struct btrfs_block_group * bg,struct extent_buffer * eb)2401 void btrfs_schedule_zone_finish_bg(struct btrfs_block_group *bg,
2402 				   struct extent_buffer *eb)
2403 {
2404 	if (!test_bit(BLOCK_GROUP_FLAG_SEQUENTIAL_ZONE, &bg->runtime_flags) ||
2405 	    eb->start + eb->len * 2 <= bg->start + bg->zone_capacity)
2406 		return;
2407 
2408 	if (WARN_ON(bg->zone_finish_work.func == btrfs_zone_finish_endio_workfn)) {
2409 		btrfs_err(bg->fs_info, "double scheduling of bg %llu zone finishing",
2410 			  bg->start);
2411 		return;
2412 	}
2413 
2414 	/* For the work */
2415 	btrfs_get_block_group(bg);
2416 	atomic_inc(&eb->refs);
2417 	bg->last_eb = eb;
2418 	INIT_WORK(&bg->zone_finish_work, btrfs_zone_finish_endio_workfn);
2419 	queue_work(system_unbound_wq, &bg->zone_finish_work);
2420 }
2421 
btrfs_clear_data_reloc_bg(struct btrfs_block_group * bg)2422 void btrfs_clear_data_reloc_bg(struct btrfs_block_group *bg)
2423 {
2424 	struct btrfs_fs_info *fs_info = bg->fs_info;
2425 
2426 	spin_lock(&fs_info->relocation_bg_lock);
2427 	if (fs_info->data_reloc_bg == bg->start)
2428 		fs_info->data_reloc_bg = 0;
2429 	spin_unlock(&fs_info->relocation_bg_lock);
2430 }
2431 
btrfs_free_zone_cache(struct btrfs_fs_info * fs_info)2432 void btrfs_free_zone_cache(struct btrfs_fs_info *fs_info)
2433 {
2434 	struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
2435 	struct btrfs_device *device;
2436 
2437 	if (!btrfs_is_zoned(fs_info))
2438 		return;
2439 
2440 	mutex_lock(&fs_devices->device_list_mutex);
2441 	list_for_each_entry(device, &fs_devices->devices, dev_list) {
2442 		if (device->zone_info) {
2443 			vfree(device->zone_info->zone_cache);
2444 			device->zone_info->zone_cache = NULL;
2445 		}
2446 	}
2447 	mutex_unlock(&fs_devices->device_list_mutex);
2448 }
2449 
btrfs_zoned_should_reclaim(const struct btrfs_fs_info * fs_info)2450 bool btrfs_zoned_should_reclaim(const struct btrfs_fs_info *fs_info)
2451 {
2452 	struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
2453 	struct btrfs_device *device;
2454 	u64 used = 0;
2455 	u64 total = 0;
2456 	u64 factor;
2457 
2458 	ASSERT(btrfs_is_zoned(fs_info));
2459 
2460 	if (fs_info->bg_reclaim_threshold == 0)
2461 		return false;
2462 
2463 	mutex_lock(&fs_devices->device_list_mutex);
2464 	list_for_each_entry(device, &fs_devices->devices, dev_list) {
2465 		if (!device->bdev)
2466 			continue;
2467 
2468 		total += device->disk_total_bytes;
2469 		used += device->bytes_used;
2470 	}
2471 	mutex_unlock(&fs_devices->device_list_mutex);
2472 
2473 	factor = div64_u64(used * 100, total);
2474 	return factor >= fs_info->bg_reclaim_threshold;
2475 }
2476 
btrfs_zoned_release_data_reloc_bg(struct btrfs_fs_info * fs_info,u64 logical,u64 length)2477 void btrfs_zoned_release_data_reloc_bg(struct btrfs_fs_info *fs_info, u64 logical,
2478 				       u64 length)
2479 {
2480 	struct btrfs_block_group *block_group;
2481 
2482 	if (!btrfs_is_zoned(fs_info))
2483 		return;
2484 
2485 	block_group = btrfs_lookup_block_group(fs_info, logical);
2486 	/* It should be called on a previous data relocation block group. */
2487 	ASSERT(block_group && (block_group->flags & BTRFS_BLOCK_GROUP_DATA));
2488 
2489 	spin_lock(&block_group->lock);
2490 	if (!test_bit(BLOCK_GROUP_FLAG_ZONED_DATA_RELOC, &block_group->runtime_flags))
2491 		goto out;
2492 
2493 	/* All relocation extents are written. */
2494 	if (block_group->start + block_group->alloc_offset == logical + length) {
2495 		/*
2496 		 * Now, release this block group for further allocations and
2497 		 * zone finish.
2498 		 */
2499 		clear_bit(BLOCK_GROUP_FLAG_ZONED_DATA_RELOC,
2500 			  &block_group->runtime_flags);
2501 	}
2502 
2503 out:
2504 	spin_unlock(&block_group->lock);
2505 	btrfs_put_block_group(block_group);
2506 }
2507 
btrfs_zone_finish_one_bg(struct btrfs_fs_info * fs_info)2508 int btrfs_zone_finish_one_bg(struct btrfs_fs_info *fs_info)
2509 {
2510 	struct btrfs_block_group *block_group;
2511 	struct btrfs_block_group *min_bg = NULL;
2512 	u64 min_avail = U64_MAX;
2513 	int ret;
2514 
2515 	spin_lock(&fs_info->zone_active_bgs_lock);
2516 	list_for_each_entry(block_group, &fs_info->zone_active_bgs,
2517 			    active_bg_list) {
2518 		u64 avail;
2519 
2520 		spin_lock(&block_group->lock);
2521 		if (block_group->reserved || block_group->alloc_offset == 0 ||
2522 		    (block_group->flags & BTRFS_BLOCK_GROUP_SYSTEM) ||
2523 		    test_bit(BLOCK_GROUP_FLAG_ZONED_DATA_RELOC, &block_group->runtime_flags)) {
2524 			spin_unlock(&block_group->lock);
2525 			continue;
2526 		}
2527 
2528 		avail = block_group->zone_capacity - block_group->alloc_offset;
2529 		if (min_avail > avail) {
2530 			if (min_bg)
2531 				btrfs_put_block_group(min_bg);
2532 			min_bg = block_group;
2533 			min_avail = avail;
2534 			btrfs_get_block_group(min_bg);
2535 		}
2536 		spin_unlock(&block_group->lock);
2537 	}
2538 	spin_unlock(&fs_info->zone_active_bgs_lock);
2539 
2540 	if (!min_bg)
2541 		return 0;
2542 
2543 	ret = btrfs_zone_finish(min_bg);
2544 	btrfs_put_block_group(min_bg);
2545 
2546 	return ret < 0 ? ret : 1;
2547 }
2548 
btrfs_zoned_activate_one_bg(struct btrfs_fs_info * fs_info,struct btrfs_space_info * space_info,bool do_finish)2549 int btrfs_zoned_activate_one_bg(struct btrfs_fs_info *fs_info,
2550 				struct btrfs_space_info *space_info,
2551 				bool do_finish)
2552 {
2553 	struct btrfs_block_group *bg;
2554 	int index;
2555 
2556 	if (!btrfs_is_zoned(fs_info) || (space_info->flags & BTRFS_BLOCK_GROUP_DATA))
2557 		return 0;
2558 
2559 	for (;;) {
2560 		int ret;
2561 		bool need_finish = false;
2562 
2563 		down_read(&space_info->groups_sem);
2564 		for (index = 0; index < BTRFS_NR_RAID_TYPES; index++) {
2565 			list_for_each_entry(bg, &space_info->block_groups[index],
2566 					    list) {
2567 				if (!spin_trylock(&bg->lock))
2568 					continue;
2569 				if (btrfs_zoned_bg_is_full(bg) ||
2570 				    test_bit(BLOCK_GROUP_FLAG_ZONE_IS_ACTIVE,
2571 					     &bg->runtime_flags)) {
2572 					spin_unlock(&bg->lock);
2573 					continue;
2574 				}
2575 				spin_unlock(&bg->lock);
2576 
2577 				if (btrfs_zone_activate(bg)) {
2578 					up_read(&space_info->groups_sem);
2579 					return 1;
2580 				}
2581 
2582 				need_finish = true;
2583 			}
2584 		}
2585 		up_read(&space_info->groups_sem);
2586 
2587 		if (!do_finish || !need_finish)
2588 			break;
2589 
2590 		ret = btrfs_zone_finish_one_bg(fs_info);
2591 		if (ret == 0)
2592 			break;
2593 		if (ret < 0)
2594 			return ret;
2595 	}
2596 
2597 	return 0;
2598 }
2599 
2600 /*
2601  * Reserve zones for one metadata block group, one tree-log block group, and one
2602  * system block group.
2603  */
btrfs_check_active_zone_reservation(struct btrfs_fs_info * fs_info)2604 void btrfs_check_active_zone_reservation(struct btrfs_fs_info *fs_info)
2605 {
2606 	struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
2607 	struct btrfs_block_group *block_group;
2608 	struct btrfs_device *device;
2609 	/* Reserve zones for normal SINGLE metadata and tree-log block group. */
2610 	unsigned int metadata_reserve = 2;
2611 	/* Reserve a zone for SINGLE system block group. */
2612 	unsigned int system_reserve = 1;
2613 
2614 	if (!test_bit(BTRFS_FS_ACTIVE_ZONE_TRACKING, &fs_info->flags))
2615 		return;
2616 
2617 	/*
2618 	 * This function is called from the mount context. So, there is no
2619 	 * parallel process touching the bits. No need for read_seqretry().
2620 	 */
2621 	if (fs_info->avail_metadata_alloc_bits & BTRFS_BLOCK_GROUP_DUP)
2622 		metadata_reserve = 4;
2623 	if (fs_info->avail_system_alloc_bits & BTRFS_BLOCK_GROUP_DUP)
2624 		system_reserve = 2;
2625 
2626 	/* Apply the reservation on all the devices. */
2627 	mutex_lock(&fs_devices->device_list_mutex);
2628 	list_for_each_entry(device, &fs_devices->devices, dev_list) {
2629 		if (!device->bdev)
2630 			continue;
2631 
2632 		device->zone_info->reserved_active_zones =
2633 			metadata_reserve + system_reserve;
2634 	}
2635 	mutex_unlock(&fs_devices->device_list_mutex);
2636 
2637 	/* Release reservation for currently active block groups. */
2638 	spin_lock(&fs_info->zone_active_bgs_lock);
2639 	list_for_each_entry(block_group, &fs_info->zone_active_bgs, active_bg_list) {
2640 		struct btrfs_chunk_map *map = block_group->physical_map;
2641 
2642 		if (!(block_group->flags &
2643 		      (BTRFS_BLOCK_GROUP_METADATA | BTRFS_BLOCK_GROUP_SYSTEM)))
2644 			continue;
2645 
2646 		for (int i = 0; i < map->num_stripes; i++)
2647 			map->stripes[i].dev->zone_info->reserved_active_zones--;
2648 	}
2649 	spin_unlock(&fs_info->zone_active_bgs_lock);
2650 }
2651