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