xref: /linux/fs/bcachefs/ec.c (revision 59fff63cc2b75dcfe08f9eeb4b2187d73e53843d)
1 // SPDX-License-Identifier: GPL-2.0
2 
3 /* erasure coding */
4 
5 #include "bcachefs.h"
6 #include "alloc_foreground.h"
7 #include "backpointers.h"
8 #include "bkey_buf.h"
9 #include "bset.h"
10 #include "btree_gc.h"
11 #include "btree_update.h"
12 #include "btree_write_buffer.h"
13 #include "buckets.h"
14 #include "checksum.h"
15 #include "disk_groups.h"
16 #include "ec.h"
17 #include "error.h"
18 #include "io_read.h"
19 #include "keylist.h"
20 #include "recovery.h"
21 #include "replicas.h"
22 #include "super-io.h"
23 #include "util.h"
24 
25 #include <linux/sort.h>
26 
27 #ifdef __KERNEL__
28 
29 #include <linux/raid/pq.h>
30 #include <linux/raid/xor.h>
31 
32 static void raid5_recov(unsigned disks, unsigned failed_idx,
33 			size_t size, void **data)
34 {
35 	unsigned i = 2, nr;
36 
37 	BUG_ON(failed_idx >= disks);
38 
39 	swap(data[0], data[failed_idx]);
40 	memcpy(data[0], data[1], size);
41 
42 	while (i < disks) {
43 		nr = min_t(unsigned, disks - i, MAX_XOR_BLOCKS);
44 		xor_blocks(nr, size, data[0], data + i);
45 		i += nr;
46 	}
47 
48 	swap(data[0], data[failed_idx]);
49 }
50 
51 static void raid_gen(int nd, int np, size_t size, void **v)
52 {
53 	if (np >= 1)
54 		raid5_recov(nd + np, nd, size, v);
55 	if (np >= 2)
56 		raid6_call.gen_syndrome(nd + np, size, v);
57 	BUG_ON(np > 2);
58 }
59 
60 static void raid_rec(int nr, int *ir, int nd, int np, size_t size, void **v)
61 {
62 	switch (nr) {
63 	case 0:
64 		break;
65 	case 1:
66 		if (ir[0] < nd + 1)
67 			raid5_recov(nd + 1, ir[0], size, v);
68 		else
69 			raid6_call.gen_syndrome(nd + np, size, v);
70 		break;
71 	case 2:
72 		if (ir[1] < nd) {
73 			/* data+data failure. */
74 			raid6_2data_recov(nd + np, size, ir[0], ir[1], v);
75 		} else if (ir[0] < nd) {
76 			/* data + p/q failure */
77 
78 			if (ir[1] == nd) /* data + p failure */
79 				raid6_datap_recov(nd + np, size, ir[0], v);
80 			else { /* data + q failure */
81 				raid5_recov(nd + 1, ir[0], size, v);
82 				raid6_call.gen_syndrome(nd + np, size, v);
83 			}
84 		} else {
85 			raid_gen(nd, np, size, v);
86 		}
87 		break;
88 	default:
89 		BUG();
90 	}
91 }
92 
93 #else
94 
95 #include <raid/raid.h>
96 
97 #endif
98 
99 struct ec_bio {
100 	struct bch_dev		*ca;
101 	struct ec_stripe_buf	*buf;
102 	size_t			idx;
103 	struct bio		bio;
104 };
105 
106 /* Stripes btree keys: */
107 
108 int bch2_stripe_invalid(const struct bch_fs *c, struct bkey_s_c k,
109 			enum bkey_invalid_flags flags,
110 			struct printbuf *err)
111 {
112 	const struct bch_stripe *s = bkey_s_c_to_stripe(k).v;
113 
114 	if (bkey_eq(k.k->p, POS_MIN)) {
115 		prt_printf(err, "stripe at POS_MIN");
116 		return -BCH_ERR_invalid_bkey;
117 	}
118 
119 	if (k.k->p.inode) {
120 		prt_printf(err, "nonzero inode field");
121 		return -BCH_ERR_invalid_bkey;
122 	}
123 
124 	if (bkey_val_u64s(k.k) < stripe_val_u64s(s)) {
125 		prt_printf(err, "incorrect value size (%zu < %u)",
126 		       bkey_val_u64s(k.k), stripe_val_u64s(s));
127 		return -BCH_ERR_invalid_bkey;
128 	}
129 
130 	return bch2_bkey_ptrs_invalid(c, k, flags, err);
131 }
132 
133 void bch2_stripe_to_text(struct printbuf *out, struct bch_fs *c,
134 			 struct bkey_s_c k)
135 {
136 	const struct bch_stripe *s = bkey_s_c_to_stripe(k).v;
137 	unsigned i, nr_data = s->nr_blocks - s->nr_redundant;
138 
139 	prt_printf(out, "algo %u sectors %u blocks %u:%u csum %u gran %u",
140 	       s->algorithm,
141 	       le16_to_cpu(s->sectors),
142 	       nr_data,
143 	       s->nr_redundant,
144 	       s->csum_type,
145 	       1U << s->csum_granularity_bits);
146 
147 	for (i = 0; i < s->nr_blocks; i++) {
148 		const struct bch_extent_ptr *ptr = s->ptrs + i;
149 		struct bch_dev *ca = bch_dev_bkey_exists(c, ptr->dev);
150 		u32 offset;
151 		u64 b = sector_to_bucket_and_offset(ca, ptr->offset, &offset);
152 
153 		prt_printf(out, " %u:%llu:%u", ptr->dev, b, offset);
154 		if (i < nr_data)
155 			prt_printf(out, "#%u", stripe_blockcount_get(s, i));
156 		if (ptr_stale(ca, ptr))
157 			prt_printf(out, " stale");
158 	}
159 }
160 
161 /* returns blocknr in stripe that we matched: */
162 static const struct bch_extent_ptr *bkey_matches_stripe(struct bch_stripe *s,
163 						struct bkey_s_c k, unsigned *block)
164 {
165 	struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
166 	const struct bch_extent_ptr *ptr;
167 	unsigned i, nr_data = s->nr_blocks - s->nr_redundant;
168 
169 	bkey_for_each_ptr(ptrs, ptr)
170 		for (i = 0; i < nr_data; i++)
171 			if (__bch2_ptr_matches_stripe(&s->ptrs[i], ptr,
172 						      le16_to_cpu(s->sectors))) {
173 				*block = i;
174 				return ptr;
175 			}
176 
177 	return NULL;
178 }
179 
180 static bool extent_has_stripe_ptr(struct bkey_s_c k, u64 idx)
181 {
182 	switch (k.k->type) {
183 	case KEY_TYPE_extent: {
184 		struct bkey_s_c_extent e = bkey_s_c_to_extent(k);
185 		const union bch_extent_entry *entry;
186 
187 		extent_for_each_entry(e, entry)
188 			if (extent_entry_type(entry) ==
189 			    BCH_EXTENT_ENTRY_stripe_ptr &&
190 			    entry->stripe_ptr.idx == idx)
191 				return true;
192 
193 		break;
194 	}
195 	}
196 
197 	return false;
198 }
199 
200 /* Stripe bufs: */
201 
202 static void ec_stripe_buf_exit(struct ec_stripe_buf *buf)
203 {
204 	if (buf->key.k.type == KEY_TYPE_stripe) {
205 		struct bkey_i_stripe *s = bkey_i_to_stripe(&buf->key);
206 		unsigned i;
207 
208 		for (i = 0; i < s->v.nr_blocks; i++) {
209 			kvpfree(buf->data[i], buf->size << 9);
210 			buf->data[i] = NULL;
211 		}
212 	}
213 }
214 
215 /* XXX: this is a non-mempoolified memory allocation: */
216 static int ec_stripe_buf_init(struct ec_stripe_buf *buf,
217 			      unsigned offset, unsigned size)
218 {
219 	struct bch_stripe *v = &bkey_i_to_stripe(&buf->key)->v;
220 	unsigned csum_granularity = 1U << v->csum_granularity_bits;
221 	unsigned end = offset + size;
222 	unsigned i;
223 
224 	BUG_ON(end > le16_to_cpu(v->sectors));
225 
226 	offset	= round_down(offset, csum_granularity);
227 	end	= min_t(unsigned, le16_to_cpu(v->sectors),
228 			round_up(end, csum_granularity));
229 
230 	buf->offset	= offset;
231 	buf->size	= end - offset;
232 
233 	memset(buf->valid, 0xFF, sizeof(buf->valid));
234 
235 	for (i = 0; i < v->nr_blocks; i++) {
236 		buf->data[i] = kvpmalloc(buf->size << 9, GFP_KERNEL);
237 		if (!buf->data[i])
238 			goto err;
239 	}
240 
241 	return 0;
242 err:
243 	ec_stripe_buf_exit(buf);
244 	return -BCH_ERR_ENOMEM_stripe_buf;
245 }
246 
247 /* Checksumming: */
248 
249 static struct bch_csum ec_block_checksum(struct ec_stripe_buf *buf,
250 					 unsigned block, unsigned offset)
251 {
252 	struct bch_stripe *v = &bkey_i_to_stripe(&buf->key)->v;
253 	unsigned csum_granularity = 1 << v->csum_granularity_bits;
254 	unsigned end = buf->offset + buf->size;
255 	unsigned len = min(csum_granularity, end - offset);
256 
257 	BUG_ON(offset >= end);
258 	BUG_ON(offset <  buf->offset);
259 	BUG_ON(offset & (csum_granularity - 1));
260 	BUG_ON(offset + len != le16_to_cpu(v->sectors) &&
261 	       (len & (csum_granularity - 1)));
262 
263 	return bch2_checksum(NULL, v->csum_type,
264 			     null_nonce(),
265 			     buf->data[block] + ((offset - buf->offset) << 9),
266 			     len << 9);
267 }
268 
269 static void ec_generate_checksums(struct ec_stripe_buf *buf)
270 {
271 	struct bch_stripe *v = &bkey_i_to_stripe(&buf->key)->v;
272 	unsigned i, j, csums_per_device = stripe_csums_per_device(v);
273 
274 	if (!v->csum_type)
275 		return;
276 
277 	BUG_ON(buf->offset);
278 	BUG_ON(buf->size != le16_to_cpu(v->sectors));
279 
280 	for (i = 0; i < v->nr_blocks; i++)
281 		for (j = 0; j < csums_per_device; j++)
282 			stripe_csum_set(v, i, j,
283 				ec_block_checksum(buf, i, j << v->csum_granularity_bits));
284 }
285 
286 static void ec_validate_checksums(struct bch_fs *c, struct ec_stripe_buf *buf)
287 {
288 	struct bch_stripe *v = &bkey_i_to_stripe(&buf->key)->v;
289 	unsigned csum_granularity = 1 << v->csum_granularity_bits;
290 	unsigned i;
291 
292 	if (!v->csum_type)
293 		return;
294 
295 	for (i = 0; i < v->nr_blocks; i++) {
296 		unsigned offset = buf->offset;
297 		unsigned end = buf->offset + buf->size;
298 
299 		if (!test_bit(i, buf->valid))
300 			continue;
301 
302 		while (offset < end) {
303 			unsigned j = offset >> v->csum_granularity_bits;
304 			unsigned len = min(csum_granularity, end - offset);
305 			struct bch_csum want = stripe_csum_get(v, i, j);
306 			struct bch_csum got = ec_block_checksum(buf, i, offset);
307 
308 			if (bch2_crc_cmp(want, got)) {
309 				struct printbuf buf2 = PRINTBUF;
310 
311 				bch2_bkey_val_to_text(&buf2, c, bkey_i_to_s_c(&buf->key));
312 
313 				bch_err_ratelimited(c,
314 					"stripe checksum error for %ps at %u:%u: csum type %u, expected %llx got %llx\n%s",
315 					(void *) _RET_IP_, i, j, v->csum_type,
316 					want.lo, got.lo, buf2.buf);
317 				printbuf_exit(&buf2);
318 				clear_bit(i, buf->valid);
319 				break;
320 			}
321 
322 			offset += len;
323 		}
324 	}
325 }
326 
327 /* Erasure coding: */
328 
329 static void ec_generate_ec(struct ec_stripe_buf *buf)
330 {
331 	struct bch_stripe *v = &bkey_i_to_stripe(&buf->key)->v;
332 	unsigned nr_data = v->nr_blocks - v->nr_redundant;
333 	unsigned bytes = le16_to_cpu(v->sectors) << 9;
334 
335 	raid_gen(nr_data, v->nr_redundant, bytes, buf->data);
336 }
337 
338 static unsigned ec_nr_failed(struct ec_stripe_buf *buf)
339 {
340 	struct bch_stripe *v = &bkey_i_to_stripe(&buf->key)->v;
341 
342 	return v->nr_blocks - bitmap_weight(buf->valid, v->nr_blocks);
343 }
344 
345 static int ec_do_recov(struct bch_fs *c, struct ec_stripe_buf *buf)
346 {
347 	struct bch_stripe *v = &bkey_i_to_stripe(&buf->key)->v;
348 	unsigned i, failed[BCH_BKEY_PTRS_MAX], nr_failed = 0;
349 	unsigned nr_data = v->nr_blocks - v->nr_redundant;
350 	unsigned bytes = buf->size << 9;
351 
352 	if (ec_nr_failed(buf) > v->nr_redundant) {
353 		bch_err_ratelimited(c,
354 			"error doing reconstruct read: unable to read enough blocks");
355 		return -1;
356 	}
357 
358 	for (i = 0; i < nr_data; i++)
359 		if (!test_bit(i, buf->valid))
360 			failed[nr_failed++] = i;
361 
362 	raid_rec(nr_failed, failed, nr_data, v->nr_redundant, bytes, buf->data);
363 	return 0;
364 }
365 
366 /* IO: */
367 
368 static void ec_block_endio(struct bio *bio)
369 {
370 	struct ec_bio *ec_bio = container_of(bio, struct ec_bio, bio);
371 	struct bch_stripe *v = &bkey_i_to_stripe(&ec_bio->buf->key)->v;
372 	struct bch_extent_ptr *ptr = &v->ptrs[ec_bio->idx];
373 	struct bch_dev *ca = ec_bio->ca;
374 	struct closure *cl = bio->bi_private;
375 
376 	if (bch2_dev_io_err_on(bio->bi_status, ca, "erasure coding %s error: %s",
377 			       bio_data_dir(bio) ? "write" : "read",
378 			       bch2_blk_status_to_str(bio->bi_status)))
379 		clear_bit(ec_bio->idx, ec_bio->buf->valid);
380 
381 	if (ptr_stale(ca, ptr)) {
382 		bch_err_ratelimited(ca->fs,
383 				    "error %s stripe: stale pointer after io",
384 				    bio_data_dir(bio) == READ ? "reading from" : "writing to");
385 		clear_bit(ec_bio->idx, ec_bio->buf->valid);
386 	}
387 
388 	bio_put(&ec_bio->bio);
389 	percpu_ref_put(&ca->io_ref);
390 	closure_put(cl);
391 }
392 
393 static void ec_block_io(struct bch_fs *c, struct ec_stripe_buf *buf,
394 			blk_opf_t opf, unsigned idx, struct closure *cl)
395 {
396 	struct bch_stripe *v = &bkey_i_to_stripe(&buf->key)->v;
397 	unsigned offset = 0, bytes = buf->size << 9;
398 	struct bch_extent_ptr *ptr = &v->ptrs[idx];
399 	struct bch_dev *ca = bch_dev_bkey_exists(c, ptr->dev);
400 	enum bch_data_type data_type = idx < v->nr_blocks - v->nr_redundant
401 		? BCH_DATA_user
402 		: BCH_DATA_parity;
403 	int rw = op_is_write(opf);
404 
405 	if (ptr_stale(ca, ptr)) {
406 		bch_err_ratelimited(c,
407 				    "error %s stripe: stale pointer",
408 				    rw == READ ? "reading from" : "writing to");
409 		clear_bit(idx, buf->valid);
410 		return;
411 	}
412 
413 	if (!bch2_dev_get_ioref(ca, rw)) {
414 		clear_bit(idx, buf->valid);
415 		return;
416 	}
417 
418 	this_cpu_add(ca->io_done->sectors[rw][data_type], buf->size);
419 
420 	while (offset < bytes) {
421 		unsigned nr_iovecs = min_t(size_t, BIO_MAX_VECS,
422 					   DIV_ROUND_UP(bytes, PAGE_SIZE));
423 		unsigned b = min_t(size_t, bytes - offset,
424 				   nr_iovecs << PAGE_SHIFT);
425 		struct ec_bio *ec_bio;
426 
427 		ec_bio = container_of(bio_alloc_bioset(ca->disk_sb.bdev,
428 						       nr_iovecs,
429 						       opf,
430 						       GFP_KERNEL,
431 						       &c->ec_bioset),
432 				      struct ec_bio, bio);
433 
434 		ec_bio->ca			= ca;
435 		ec_bio->buf			= buf;
436 		ec_bio->idx			= idx;
437 
438 		ec_bio->bio.bi_iter.bi_sector	= ptr->offset + buf->offset + (offset >> 9);
439 		ec_bio->bio.bi_end_io		= ec_block_endio;
440 		ec_bio->bio.bi_private		= cl;
441 
442 		bch2_bio_map(&ec_bio->bio, buf->data[idx] + offset, b);
443 
444 		closure_get(cl);
445 		percpu_ref_get(&ca->io_ref);
446 
447 		submit_bio(&ec_bio->bio);
448 
449 		offset += b;
450 	}
451 
452 	percpu_ref_put(&ca->io_ref);
453 }
454 
455 static int get_stripe_key_trans(struct btree_trans *trans, u64 idx,
456 				struct ec_stripe_buf *stripe)
457 {
458 	struct btree_iter iter;
459 	struct bkey_s_c k;
460 	int ret;
461 
462 	k = bch2_bkey_get_iter(trans, &iter, BTREE_ID_stripes,
463 			       POS(0, idx), BTREE_ITER_SLOTS);
464 	ret = bkey_err(k);
465 	if (ret)
466 		goto err;
467 	if (k.k->type != KEY_TYPE_stripe) {
468 		ret = -ENOENT;
469 		goto err;
470 	}
471 	bkey_reassemble(&stripe->key, k);
472 err:
473 	bch2_trans_iter_exit(trans, &iter);
474 	return ret;
475 }
476 
477 static int get_stripe_key(struct bch_fs *c, u64 idx, struct ec_stripe_buf *stripe)
478 {
479 	return bch2_trans_run(c, get_stripe_key_trans(trans, idx, stripe));
480 }
481 
482 /* recovery read path: */
483 int bch2_ec_read_extent(struct bch_fs *c, struct bch_read_bio *rbio)
484 {
485 	struct ec_stripe_buf *buf;
486 	struct closure cl;
487 	struct bch_stripe *v;
488 	unsigned i, offset;
489 	int ret = 0;
490 
491 	closure_init_stack(&cl);
492 
493 	BUG_ON(!rbio->pick.has_ec);
494 
495 	buf = kzalloc(sizeof(*buf), GFP_NOFS);
496 	if (!buf)
497 		return -BCH_ERR_ENOMEM_ec_read_extent;
498 
499 	ret = get_stripe_key(c, rbio->pick.ec.idx, buf);
500 	if (ret) {
501 		bch_err_ratelimited(c,
502 			"error doing reconstruct read: error %i looking up stripe", ret);
503 		kfree(buf);
504 		return -EIO;
505 	}
506 
507 	v = &bkey_i_to_stripe(&buf->key)->v;
508 
509 	if (!bch2_ptr_matches_stripe(v, rbio->pick)) {
510 		bch_err_ratelimited(c,
511 			"error doing reconstruct read: pointer doesn't match stripe");
512 		ret = -EIO;
513 		goto err;
514 	}
515 
516 	offset = rbio->bio.bi_iter.bi_sector - v->ptrs[rbio->pick.ec.block].offset;
517 	if (offset + bio_sectors(&rbio->bio) > le16_to_cpu(v->sectors)) {
518 		bch_err_ratelimited(c,
519 			"error doing reconstruct read: read is bigger than stripe");
520 		ret = -EIO;
521 		goto err;
522 	}
523 
524 	ret = ec_stripe_buf_init(buf, offset, bio_sectors(&rbio->bio));
525 	if (ret)
526 		goto err;
527 
528 	for (i = 0; i < v->nr_blocks; i++)
529 		ec_block_io(c, buf, REQ_OP_READ, i, &cl);
530 
531 	closure_sync(&cl);
532 
533 	if (ec_nr_failed(buf) > v->nr_redundant) {
534 		bch_err_ratelimited(c,
535 			"error doing reconstruct read: unable to read enough blocks");
536 		ret = -EIO;
537 		goto err;
538 	}
539 
540 	ec_validate_checksums(c, buf);
541 
542 	ret = ec_do_recov(c, buf);
543 	if (ret)
544 		goto err;
545 
546 	memcpy_to_bio(&rbio->bio, rbio->bio.bi_iter,
547 		      buf->data[rbio->pick.ec.block] + ((offset - buf->offset) << 9));
548 err:
549 	ec_stripe_buf_exit(buf);
550 	kfree(buf);
551 	return ret;
552 }
553 
554 /* stripe bucket accounting: */
555 
556 static int __ec_stripe_mem_alloc(struct bch_fs *c, size_t idx, gfp_t gfp)
557 {
558 	ec_stripes_heap n, *h = &c->ec_stripes_heap;
559 
560 	if (idx >= h->size) {
561 		if (!init_heap(&n, max(1024UL, roundup_pow_of_two(idx + 1)), gfp))
562 			return -BCH_ERR_ENOMEM_ec_stripe_mem_alloc;
563 
564 		mutex_lock(&c->ec_stripes_heap_lock);
565 		if (n.size > h->size) {
566 			memcpy(n.data, h->data, h->used * sizeof(h->data[0]));
567 			n.used = h->used;
568 			swap(*h, n);
569 		}
570 		mutex_unlock(&c->ec_stripes_heap_lock);
571 
572 		free_heap(&n);
573 	}
574 
575 	if (!genradix_ptr_alloc(&c->stripes, idx, gfp))
576 		return -BCH_ERR_ENOMEM_ec_stripe_mem_alloc;
577 
578 	if (c->gc_pos.phase != GC_PHASE_NOT_RUNNING &&
579 	    !genradix_ptr_alloc(&c->gc_stripes, idx, gfp))
580 		return -BCH_ERR_ENOMEM_ec_stripe_mem_alloc;
581 
582 	return 0;
583 }
584 
585 static int ec_stripe_mem_alloc(struct btree_trans *trans,
586 			       struct btree_iter *iter)
587 {
588 	return allocate_dropping_locks_errcode(trans,
589 			__ec_stripe_mem_alloc(trans->c, iter->pos.offset, _gfp));
590 }
591 
592 /*
593  * Hash table of open stripes:
594  * Stripes that are being created or modified are kept in a hash table, so that
595  * stripe deletion can skip them.
596  */
597 
598 static bool __bch2_stripe_is_open(struct bch_fs *c, u64 idx)
599 {
600 	unsigned hash = hash_64(idx, ilog2(ARRAY_SIZE(c->ec_stripes_new)));
601 	struct ec_stripe_new *s;
602 
603 	hlist_for_each_entry(s, &c->ec_stripes_new[hash], hash)
604 		if (s->idx == idx)
605 			return true;
606 	return false;
607 }
608 
609 static bool bch2_stripe_is_open(struct bch_fs *c, u64 idx)
610 {
611 	bool ret = false;
612 
613 	spin_lock(&c->ec_stripes_new_lock);
614 	ret = __bch2_stripe_is_open(c, idx);
615 	spin_unlock(&c->ec_stripes_new_lock);
616 
617 	return ret;
618 }
619 
620 static bool bch2_try_open_stripe(struct bch_fs *c,
621 				 struct ec_stripe_new *s,
622 				 u64 idx)
623 {
624 	bool ret;
625 
626 	spin_lock(&c->ec_stripes_new_lock);
627 	ret = !__bch2_stripe_is_open(c, idx);
628 	if (ret) {
629 		unsigned hash = hash_64(idx, ilog2(ARRAY_SIZE(c->ec_stripes_new)));
630 
631 		s->idx = idx;
632 		hlist_add_head(&s->hash, &c->ec_stripes_new[hash]);
633 	}
634 	spin_unlock(&c->ec_stripes_new_lock);
635 
636 	return ret;
637 }
638 
639 static void bch2_stripe_close(struct bch_fs *c, struct ec_stripe_new *s)
640 {
641 	BUG_ON(!s->idx);
642 
643 	spin_lock(&c->ec_stripes_new_lock);
644 	hlist_del_init(&s->hash);
645 	spin_unlock(&c->ec_stripes_new_lock);
646 
647 	s->idx = 0;
648 }
649 
650 /* Heap of all existing stripes, ordered by blocks_nonempty */
651 
652 static u64 stripe_idx_to_delete(struct bch_fs *c)
653 {
654 	ec_stripes_heap *h = &c->ec_stripes_heap;
655 
656 	lockdep_assert_held(&c->ec_stripes_heap_lock);
657 
658 	if (h->used &&
659 	    h->data[0].blocks_nonempty == 0 &&
660 	    !bch2_stripe_is_open(c, h->data[0].idx))
661 		return h->data[0].idx;
662 
663 	return 0;
664 }
665 
666 static inline int ec_stripes_heap_cmp(ec_stripes_heap *h,
667 				      struct ec_stripe_heap_entry l,
668 				      struct ec_stripe_heap_entry r)
669 {
670 	return ((l.blocks_nonempty > r.blocks_nonempty) -
671 		(l.blocks_nonempty < r.blocks_nonempty));
672 }
673 
674 static inline void ec_stripes_heap_set_backpointer(ec_stripes_heap *h,
675 						   size_t i)
676 {
677 	struct bch_fs *c = container_of(h, struct bch_fs, ec_stripes_heap);
678 
679 	genradix_ptr(&c->stripes, h->data[i].idx)->heap_idx = i;
680 }
681 
682 static void heap_verify_backpointer(struct bch_fs *c, size_t idx)
683 {
684 	ec_stripes_heap *h = &c->ec_stripes_heap;
685 	struct stripe *m = genradix_ptr(&c->stripes, idx);
686 
687 	BUG_ON(m->heap_idx >= h->used);
688 	BUG_ON(h->data[m->heap_idx].idx != idx);
689 }
690 
691 void bch2_stripes_heap_del(struct bch_fs *c,
692 			   struct stripe *m, size_t idx)
693 {
694 	mutex_lock(&c->ec_stripes_heap_lock);
695 	heap_verify_backpointer(c, idx);
696 
697 	heap_del(&c->ec_stripes_heap, m->heap_idx,
698 		 ec_stripes_heap_cmp,
699 		 ec_stripes_heap_set_backpointer);
700 	mutex_unlock(&c->ec_stripes_heap_lock);
701 }
702 
703 void bch2_stripes_heap_insert(struct bch_fs *c,
704 			      struct stripe *m, size_t idx)
705 {
706 	mutex_lock(&c->ec_stripes_heap_lock);
707 	BUG_ON(heap_full(&c->ec_stripes_heap));
708 
709 	heap_add(&c->ec_stripes_heap, ((struct ec_stripe_heap_entry) {
710 			.idx = idx,
711 			.blocks_nonempty = m->blocks_nonempty,
712 		}),
713 		 ec_stripes_heap_cmp,
714 		 ec_stripes_heap_set_backpointer);
715 
716 	heap_verify_backpointer(c, idx);
717 	mutex_unlock(&c->ec_stripes_heap_lock);
718 }
719 
720 void bch2_stripes_heap_update(struct bch_fs *c,
721 			      struct stripe *m, size_t idx)
722 {
723 	ec_stripes_heap *h = &c->ec_stripes_heap;
724 	bool do_deletes;
725 	size_t i;
726 
727 	mutex_lock(&c->ec_stripes_heap_lock);
728 	heap_verify_backpointer(c, idx);
729 
730 	h->data[m->heap_idx].blocks_nonempty = m->blocks_nonempty;
731 
732 	i = m->heap_idx;
733 	heap_sift_up(h,	  i, ec_stripes_heap_cmp,
734 		     ec_stripes_heap_set_backpointer);
735 	heap_sift_down(h, i, ec_stripes_heap_cmp,
736 		       ec_stripes_heap_set_backpointer);
737 
738 	heap_verify_backpointer(c, idx);
739 
740 	do_deletes = stripe_idx_to_delete(c) != 0;
741 	mutex_unlock(&c->ec_stripes_heap_lock);
742 
743 	if (do_deletes)
744 		bch2_do_stripe_deletes(c);
745 }
746 
747 /* stripe deletion */
748 
749 static int ec_stripe_delete(struct btree_trans *trans, u64 idx)
750 {
751 	struct bch_fs *c = trans->c;
752 	struct btree_iter iter;
753 	struct bkey_s_c k;
754 	struct bkey_s_c_stripe s;
755 	int ret;
756 
757 	k = bch2_bkey_get_iter(trans, &iter, BTREE_ID_stripes, POS(0, idx),
758 			       BTREE_ITER_INTENT);
759 	ret = bkey_err(k);
760 	if (ret)
761 		goto err;
762 
763 	if (k.k->type != KEY_TYPE_stripe) {
764 		bch2_fs_inconsistent(c, "attempting to delete nonexistent stripe %llu", idx);
765 		ret = -EINVAL;
766 		goto err;
767 	}
768 
769 	s = bkey_s_c_to_stripe(k);
770 	for (unsigned i = 0; i < s.v->nr_blocks; i++)
771 		if (stripe_blockcount_get(s.v, i)) {
772 			struct printbuf buf = PRINTBUF;
773 
774 			bch2_bkey_val_to_text(&buf, c, k);
775 			bch2_fs_inconsistent(c, "attempting to delete nonempty stripe %s", buf.buf);
776 			printbuf_exit(&buf);
777 			ret = -EINVAL;
778 			goto err;
779 		}
780 
781 	ret = bch2_btree_delete_at(trans, &iter, 0);
782 err:
783 	bch2_trans_iter_exit(trans, &iter);
784 	return ret;
785 }
786 
787 static void ec_stripe_delete_work(struct work_struct *work)
788 {
789 	struct bch_fs *c =
790 		container_of(work, struct bch_fs, ec_stripe_delete_work);
791 	struct btree_trans *trans = bch2_trans_get(c);
792 	int ret;
793 	u64 idx;
794 
795 	while (1) {
796 		mutex_lock(&c->ec_stripes_heap_lock);
797 		idx = stripe_idx_to_delete(c);
798 		mutex_unlock(&c->ec_stripes_heap_lock);
799 
800 		if (!idx)
801 			break;
802 
803 		ret = commit_do(trans, NULL, NULL, BTREE_INSERT_NOFAIL,
804 				ec_stripe_delete(trans, idx));
805 		if (ret) {
806 			bch_err_fn(c, ret);
807 			break;
808 		}
809 	}
810 
811 	bch2_trans_put(trans);
812 
813 	bch2_write_ref_put(c, BCH_WRITE_REF_stripe_delete);
814 }
815 
816 void bch2_do_stripe_deletes(struct bch_fs *c)
817 {
818 	if (bch2_write_ref_tryget(c, BCH_WRITE_REF_stripe_delete) &&
819 	    !queue_work(c->write_ref_wq, &c->ec_stripe_delete_work))
820 		bch2_write_ref_put(c, BCH_WRITE_REF_stripe_delete);
821 }
822 
823 /* stripe creation: */
824 
825 static int ec_stripe_key_update(struct btree_trans *trans,
826 				struct bkey_i_stripe *new,
827 				bool create)
828 {
829 	struct bch_fs *c = trans->c;
830 	struct btree_iter iter;
831 	struct bkey_s_c k;
832 	int ret;
833 
834 	k = bch2_bkey_get_iter(trans, &iter, BTREE_ID_stripes,
835 			       new->k.p, BTREE_ITER_INTENT);
836 	ret = bkey_err(k);
837 	if (ret)
838 		goto err;
839 
840 	if (k.k->type != (create ? KEY_TYPE_deleted : KEY_TYPE_stripe)) {
841 		bch2_fs_inconsistent(c, "error %s stripe: got existing key type %s",
842 				     create ? "creating" : "updating",
843 				     bch2_bkey_types[k.k->type]);
844 		ret = -EINVAL;
845 		goto err;
846 	}
847 
848 	if (k.k->type == KEY_TYPE_stripe) {
849 		const struct bch_stripe *old = bkey_s_c_to_stripe(k).v;
850 		unsigned i;
851 
852 		if (old->nr_blocks != new->v.nr_blocks) {
853 			bch_err(c, "error updating stripe: nr_blocks does not match");
854 			ret = -EINVAL;
855 			goto err;
856 		}
857 
858 		for (i = 0; i < new->v.nr_blocks; i++) {
859 			unsigned v = stripe_blockcount_get(old, i);
860 
861 			BUG_ON(v &&
862 			       (old->ptrs[i].dev != new->v.ptrs[i].dev ||
863 				old->ptrs[i].gen != new->v.ptrs[i].gen ||
864 				old->ptrs[i].offset != new->v.ptrs[i].offset));
865 
866 			stripe_blockcount_set(&new->v, i, v);
867 		}
868 	}
869 
870 	ret = bch2_trans_update(trans, &iter, &new->k_i, 0);
871 err:
872 	bch2_trans_iter_exit(trans, &iter);
873 	return ret;
874 }
875 
876 static int ec_stripe_update_extent(struct btree_trans *trans,
877 				   struct bpos bucket, u8 gen,
878 				   struct ec_stripe_buf *s,
879 				   struct bpos *bp_pos)
880 {
881 	struct bch_stripe *v = &bkey_i_to_stripe(&s->key)->v;
882 	struct bch_fs *c = trans->c;
883 	struct bch_backpointer bp;
884 	struct btree_iter iter;
885 	struct bkey_s_c k;
886 	const struct bch_extent_ptr *ptr_c;
887 	struct bch_extent_ptr *ptr, *ec_ptr = NULL;
888 	struct bch_extent_stripe_ptr stripe_ptr;
889 	struct bkey_i *n;
890 	int ret, dev, block;
891 
892 	ret = bch2_get_next_backpointer(trans, bucket, gen,
893 				bp_pos, &bp, BTREE_ITER_CACHED);
894 	if (ret)
895 		return ret;
896 	if (bpos_eq(*bp_pos, SPOS_MAX))
897 		return 0;
898 
899 	if (bp.level) {
900 		struct printbuf buf = PRINTBUF;
901 		struct btree_iter node_iter;
902 		struct btree *b;
903 
904 		b = bch2_backpointer_get_node(trans, &node_iter, *bp_pos, bp);
905 		bch2_trans_iter_exit(trans, &node_iter);
906 
907 		if (!b)
908 			return 0;
909 
910 		prt_printf(&buf, "found btree node in erasure coded bucket: b=%px\n", b);
911 		bch2_backpointer_to_text(&buf, &bp);
912 
913 		bch2_fs_inconsistent(c, "%s", buf.buf);
914 		printbuf_exit(&buf);
915 		return -EIO;
916 	}
917 
918 	k = bch2_backpointer_get_key(trans, &iter, *bp_pos, bp, BTREE_ITER_INTENT);
919 	ret = bkey_err(k);
920 	if (ret)
921 		return ret;
922 	if (!k.k) {
923 		/*
924 		 * extent no longer exists - we could flush the btree
925 		 * write buffer and retry to verify, but no need:
926 		 */
927 		return 0;
928 	}
929 
930 	if (extent_has_stripe_ptr(k, s->key.k.p.offset))
931 		goto out;
932 
933 	ptr_c = bkey_matches_stripe(v, k, &block);
934 	/*
935 	 * It doesn't generally make sense to erasure code cached ptrs:
936 	 * XXX: should we be incrementing a counter?
937 	 */
938 	if (!ptr_c || ptr_c->cached)
939 		goto out;
940 
941 	dev = v->ptrs[block].dev;
942 
943 	n = bch2_trans_kmalloc(trans, bkey_bytes(k.k) + sizeof(stripe_ptr));
944 	ret = PTR_ERR_OR_ZERO(n);
945 	if (ret)
946 		goto out;
947 
948 	bkey_reassemble(n, k);
949 
950 	bch2_bkey_drop_ptrs(bkey_i_to_s(n), ptr, ptr->dev != dev);
951 	ec_ptr = bch2_bkey_has_device(bkey_i_to_s(n), dev);
952 	BUG_ON(!ec_ptr);
953 
954 	stripe_ptr = (struct bch_extent_stripe_ptr) {
955 		.type = 1 << BCH_EXTENT_ENTRY_stripe_ptr,
956 		.block		= block,
957 		.redundancy	= v->nr_redundant,
958 		.idx		= s->key.k.p.offset,
959 	};
960 
961 	__extent_entry_insert(n,
962 			(union bch_extent_entry *) ec_ptr,
963 			(union bch_extent_entry *) &stripe_ptr);
964 
965 	ret = bch2_trans_update(trans, &iter, n, 0);
966 out:
967 	bch2_trans_iter_exit(trans, &iter);
968 	return ret;
969 }
970 
971 static int ec_stripe_update_bucket(struct btree_trans *trans, struct ec_stripe_buf *s,
972 				   unsigned block)
973 {
974 	struct bch_fs *c = trans->c;
975 	struct bch_stripe *v = &bkey_i_to_stripe(&s->key)->v;
976 	struct bch_extent_ptr bucket = v->ptrs[block];
977 	struct bpos bucket_pos = PTR_BUCKET_POS(c, &bucket);
978 	struct bpos bp_pos = POS_MIN;
979 	int ret = 0;
980 
981 	while (1) {
982 		ret = commit_do(trans, NULL, NULL,
983 				BTREE_INSERT_NOCHECK_RW|
984 				BTREE_INSERT_NOFAIL,
985 			ec_stripe_update_extent(trans, bucket_pos, bucket.gen,
986 						s, &bp_pos));
987 		if (ret)
988 			break;
989 		if (bkey_eq(bp_pos, POS_MAX))
990 			break;
991 
992 		bp_pos = bpos_nosnap_successor(bp_pos);
993 	}
994 
995 	return ret;
996 }
997 
998 static int ec_stripe_update_extents(struct bch_fs *c, struct ec_stripe_buf *s)
999 {
1000 	struct btree_trans *trans = bch2_trans_get(c);
1001 	struct bch_stripe *v = &bkey_i_to_stripe(&s->key)->v;
1002 	unsigned i, nr_data = v->nr_blocks - v->nr_redundant;
1003 	int ret = 0;
1004 
1005 	ret = bch2_btree_write_buffer_flush(trans);
1006 	if (ret)
1007 		goto err;
1008 
1009 	for (i = 0; i < nr_data; i++) {
1010 		ret = ec_stripe_update_bucket(trans, s, i);
1011 		if (ret)
1012 			break;
1013 	}
1014 err:
1015 	bch2_trans_put(trans);
1016 
1017 	return ret;
1018 }
1019 
1020 static void zero_out_rest_of_ec_bucket(struct bch_fs *c,
1021 				       struct ec_stripe_new *s,
1022 				       unsigned block,
1023 				       struct open_bucket *ob)
1024 {
1025 	struct bch_dev *ca = bch_dev_bkey_exists(c, ob->dev);
1026 	unsigned offset = ca->mi.bucket_size - ob->sectors_free;
1027 	int ret;
1028 
1029 	if (!bch2_dev_get_ioref(ca, WRITE)) {
1030 		s->err = -BCH_ERR_erofs_no_writes;
1031 		return;
1032 	}
1033 
1034 	memset(s->new_stripe.data[block] + (offset << 9),
1035 	       0,
1036 	       ob->sectors_free << 9);
1037 
1038 	ret = blkdev_issue_zeroout(ca->disk_sb.bdev,
1039 			ob->bucket * ca->mi.bucket_size + offset,
1040 			ob->sectors_free,
1041 			GFP_KERNEL, 0);
1042 
1043 	percpu_ref_put(&ca->io_ref);
1044 
1045 	if (ret)
1046 		s->err = ret;
1047 }
1048 
1049 void bch2_ec_stripe_new_free(struct bch_fs *c, struct ec_stripe_new *s)
1050 {
1051 	if (s->idx)
1052 		bch2_stripe_close(c, s);
1053 	kfree(s);
1054 }
1055 
1056 /*
1057  * data buckets of new stripe all written: create the stripe
1058  */
1059 static void ec_stripe_create(struct ec_stripe_new *s)
1060 {
1061 	struct bch_fs *c = s->c;
1062 	struct open_bucket *ob;
1063 	struct bch_stripe *v = &bkey_i_to_stripe(&s->new_stripe.key)->v;
1064 	unsigned i, nr_data = v->nr_blocks - v->nr_redundant;
1065 	int ret;
1066 
1067 	BUG_ON(s->h->s == s);
1068 
1069 	closure_sync(&s->iodone);
1070 
1071 	if (!s->err) {
1072 		for (i = 0; i < nr_data; i++)
1073 			if (s->blocks[i]) {
1074 				ob = c->open_buckets + s->blocks[i];
1075 
1076 				if (ob->sectors_free)
1077 					zero_out_rest_of_ec_bucket(c, s, i, ob);
1078 			}
1079 	}
1080 
1081 	if (s->err) {
1082 		if (!bch2_err_matches(s->err, EROFS))
1083 			bch_err(c, "error creating stripe: error writing data buckets");
1084 		goto err;
1085 	}
1086 
1087 	if (s->have_existing_stripe) {
1088 		ec_validate_checksums(c, &s->existing_stripe);
1089 
1090 		if (ec_do_recov(c, &s->existing_stripe)) {
1091 			bch_err(c, "error creating stripe: error reading existing stripe");
1092 			goto err;
1093 		}
1094 
1095 		for (i = 0; i < nr_data; i++)
1096 			if (stripe_blockcount_get(&bkey_i_to_stripe(&s->existing_stripe.key)->v, i))
1097 				swap(s->new_stripe.data[i],
1098 				     s->existing_stripe.data[i]);
1099 
1100 		ec_stripe_buf_exit(&s->existing_stripe);
1101 	}
1102 
1103 	BUG_ON(!s->allocated);
1104 	BUG_ON(!s->idx);
1105 
1106 	ec_generate_ec(&s->new_stripe);
1107 
1108 	ec_generate_checksums(&s->new_stripe);
1109 
1110 	/* write p/q: */
1111 	for (i = nr_data; i < v->nr_blocks; i++)
1112 		ec_block_io(c, &s->new_stripe, REQ_OP_WRITE, i, &s->iodone);
1113 	closure_sync(&s->iodone);
1114 
1115 	if (ec_nr_failed(&s->new_stripe)) {
1116 		bch_err(c, "error creating stripe: error writing redundancy buckets");
1117 		goto err;
1118 	}
1119 
1120 	ret = bch2_trans_do(c, &s->res, NULL,
1121 			    BTREE_INSERT_NOCHECK_RW|
1122 			    BTREE_INSERT_NOFAIL,
1123 			    ec_stripe_key_update(trans,
1124 					bkey_i_to_stripe(&s->new_stripe.key),
1125 					!s->have_existing_stripe));
1126 	if (ret) {
1127 		bch_err(c, "error creating stripe: error creating stripe key");
1128 		goto err;
1129 	}
1130 
1131 	ret = ec_stripe_update_extents(c, &s->new_stripe);
1132 	if (ret) {
1133 		bch_err_msg(c, ret, "creating stripe: error updating pointers");
1134 		goto err;
1135 	}
1136 err:
1137 	bch2_disk_reservation_put(c, &s->res);
1138 
1139 	for (i = 0; i < v->nr_blocks; i++)
1140 		if (s->blocks[i]) {
1141 			ob = c->open_buckets + s->blocks[i];
1142 
1143 			if (i < nr_data) {
1144 				ob->ec = NULL;
1145 				__bch2_open_bucket_put(c, ob);
1146 			} else {
1147 				bch2_open_bucket_put(c, ob);
1148 			}
1149 		}
1150 
1151 	mutex_lock(&c->ec_stripe_new_lock);
1152 	list_del(&s->list);
1153 	mutex_unlock(&c->ec_stripe_new_lock);
1154 	wake_up(&c->ec_stripe_new_wait);
1155 
1156 	ec_stripe_buf_exit(&s->existing_stripe);
1157 	ec_stripe_buf_exit(&s->new_stripe);
1158 	closure_debug_destroy(&s->iodone);
1159 
1160 	ec_stripe_new_put(c, s, STRIPE_REF_stripe);
1161 }
1162 
1163 static struct ec_stripe_new *get_pending_stripe(struct bch_fs *c)
1164 {
1165 	struct ec_stripe_new *s;
1166 
1167 	mutex_lock(&c->ec_stripe_new_lock);
1168 	list_for_each_entry(s, &c->ec_stripe_new_list, list)
1169 		if (!atomic_read(&s->ref[STRIPE_REF_io]))
1170 			goto out;
1171 	s = NULL;
1172 out:
1173 	mutex_unlock(&c->ec_stripe_new_lock);
1174 
1175 	return s;
1176 }
1177 
1178 static void ec_stripe_create_work(struct work_struct *work)
1179 {
1180 	struct bch_fs *c = container_of(work,
1181 		struct bch_fs, ec_stripe_create_work);
1182 	struct ec_stripe_new *s;
1183 
1184 	while ((s = get_pending_stripe(c)))
1185 		ec_stripe_create(s);
1186 
1187 	bch2_write_ref_put(c, BCH_WRITE_REF_stripe_create);
1188 }
1189 
1190 void bch2_ec_do_stripe_creates(struct bch_fs *c)
1191 {
1192 	bch2_write_ref_get(c, BCH_WRITE_REF_stripe_create);
1193 
1194 	if (!queue_work(system_long_wq, &c->ec_stripe_create_work))
1195 		bch2_write_ref_put(c, BCH_WRITE_REF_stripe_create);
1196 }
1197 
1198 static void ec_stripe_set_pending(struct bch_fs *c, struct ec_stripe_head *h)
1199 {
1200 	struct ec_stripe_new *s = h->s;
1201 
1202 	BUG_ON(!s->allocated && !s->err);
1203 
1204 	h->s		= NULL;
1205 	s->pending	= true;
1206 
1207 	mutex_lock(&c->ec_stripe_new_lock);
1208 	list_add(&s->list, &c->ec_stripe_new_list);
1209 	mutex_unlock(&c->ec_stripe_new_lock);
1210 
1211 	ec_stripe_new_put(c, s, STRIPE_REF_io);
1212 }
1213 
1214 void bch2_ec_bucket_cancel(struct bch_fs *c, struct open_bucket *ob)
1215 {
1216 	struct ec_stripe_new *s = ob->ec;
1217 
1218 	s->err = -EIO;
1219 }
1220 
1221 void *bch2_writepoint_ec_buf(struct bch_fs *c, struct write_point *wp)
1222 {
1223 	struct open_bucket *ob = ec_open_bucket(c, &wp->ptrs);
1224 	struct bch_dev *ca;
1225 	unsigned offset;
1226 
1227 	if (!ob)
1228 		return NULL;
1229 
1230 	BUG_ON(!ob->ec->new_stripe.data[ob->ec_idx]);
1231 
1232 	ca	= bch_dev_bkey_exists(c, ob->dev);
1233 	offset	= ca->mi.bucket_size - ob->sectors_free;
1234 
1235 	return ob->ec->new_stripe.data[ob->ec_idx] + (offset << 9);
1236 }
1237 
1238 static int unsigned_cmp(const void *_l, const void *_r)
1239 {
1240 	unsigned l = *((const unsigned *) _l);
1241 	unsigned r = *((const unsigned *) _r);
1242 
1243 	return cmp_int(l, r);
1244 }
1245 
1246 /* pick most common bucket size: */
1247 static unsigned pick_blocksize(struct bch_fs *c,
1248 			       struct bch_devs_mask *devs)
1249 {
1250 	struct bch_dev *ca;
1251 	unsigned i, nr = 0, sizes[BCH_SB_MEMBERS_MAX];
1252 	struct {
1253 		unsigned nr, size;
1254 	} cur = { 0, 0 }, best = { 0, 0 };
1255 
1256 	for_each_member_device_rcu(ca, c, i, devs)
1257 		sizes[nr++] = ca->mi.bucket_size;
1258 
1259 	sort(sizes, nr, sizeof(unsigned), unsigned_cmp, NULL);
1260 
1261 	for (i = 0; i < nr; i++) {
1262 		if (sizes[i] != cur.size) {
1263 			if (cur.nr > best.nr)
1264 				best = cur;
1265 
1266 			cur.nr = 0;
1267 			cur.size = sizes[i];
1268 		}
1269 
1270 		cur.nr++;
1271 	}
1272 
1273 	if (cur.nr > best.nr)
1274 		best = cur;
1275 
1276 	return best.size;
1277 }
1278 
1279 static bool may_create_new_stripe(struct bch_fs *c)
1280 {
1281 	return false;
1282 }
1283 
1284 static void ec_stripe_key_init(struct bch_fs *c,
1285 			       struct bkey_i *k,
1286 			       unsigned nr_data,
1287 			       unsigned nr_parity,
1288 			       unsigned stripe_size)
1289 {
1290 	struct bkey_i_stripe *s = bkey_stripe_init(k);
1291 	unsigned u64s;
1292 
1293 	s->v.sectors			= cpu_to_le16(stripe_size);
1294 	s->v.algorithm			= 0;
1295 	s->v.nr_blocks			= nr_data + nr_parity;
1296 	s->v.nr_redundant		= nr_parity;
1297 	s->v.csum_granularity_bits	= ilog2(c->opts.encoded_extent_max >> 9);
1298 	s->v.csum_type			= BCH_CSUM_crc32c;
1299 	s->v.pad			= 0;
1300 
1301 	while ((u64s = stripe_val_u64s(&s->v)) > BKEY_VAL_U64s_MAX) {
1302 		BUG_ON(1 << s->v.csum_granularity_bits >=
1303 		       le16_to_cpu(s->v.sectors) ||
1304 		       s->v.csum_granularity_bits == U8_MAX);
1305 		s->v.csum_granularity_bits++;
1306 	}
1307 
1308 	set_bkey_val_u64s(&s->k, u64s);
1309 }
1310 
1311 static int ec_new_stripe_alloc(struct bch_fs *c, struct ec_stripe_head *h)
1312 {
1313 	struct ec_stripe_new *s;
1314 
1315 	lockdep_assert_held(&h->lock);
1316 
1317 	s = kzalloc(sizeof(*s), GFP_KERNEL);
1318 	if (!s)
1319 		return -BCH_ERR_ENOMEM_ec_new_stripe_alloc;
1320 
1321 	mutex_init(&s->lock);
1322 	closure_init(&s->iodone, NULL);
1323 	atomic_set(&s->ref[STRIPE_REF_stripe], 1);
1324 	atomic_set(&s->ref[STRIPE_REF_io], 1);
1325 	s->c		= c;
1326 	s->h		= h;
1327 	s->nr_data	= min_t(unsigned, h->nr_active_devs,
1328 				BCH_BKEY_PTRS_MAX) - h->redundancy;
1329 	s->nr_parity	= h->redundancy;
1330 
1331 	ec_stripe_key_init(c, &s->new_stripe.key,
1332 			   s->nr_data, s->nr_parity, h->blocksize);
1333 
1334 	h->s = s;
1335 	return 0;
1336 }
1337 
1338 static struct ec_stripe_head *
1339 ec_new_stripe_head_alloc(struct bch_fs *c, unsigned target,
1340 			 unsigned algo, unsigned redundancy,
1341 			 enum bch_watermark watermark)
1342 {
1343 	struct ec_stripe_head *h;
1344 	struct bch_dev *ca;
1345 	unsigned i;
1346 
1347 	h = kzalloc(sizeof(*h), GFP_KERNEL);
1348 	if (!h)
1349 		return NULL;
1350 
1351 	mutex_init(&h->lock);
1352 	BUG_ON(!mutex_trylock(&h->lock));
1353 
1354 	h->target	= target;
1355 	h->algo		= algo;
1356 	h->redundancy	= redundancy;
1357 	h->watermark	= watermark;
1358 
1359 	rcu_read_lock();
1360 	h->devs = target_rw_devs(c, BCH_DATA_user, target);
1361 
1362 	for_each_member_device_rcu(ca, c, i, &h->devs)
1363 		if (!ca->mi.durability)
1364 			__clear_bit(i, h->devs.d);
1365 
1366 	h->blocksize = pick_blocksize(c, &h->devs);
1367 
1368 	for_each_member_device_rcu(ca, c, i, &h->devs)
1369 		if (ca->mi.bucket_size == h->blocksize)
1370 			h->nr_active_devs++;
1371 
1372 	rcu_read_unlock();
1373 	list_add(&h->list, &c->ec_stripe_head_list);
1374 	return h;
1375 }
1376 
1377 void bch2_ec_stripe_head_put(struct bch_fs *c, struct ec_stripe_head *h)
1378 {
1379 	if (h->s &&
1380 	    h->s->allocated &&
1381 	    bitmap_weight(h->s->blocks_allocated,
1382 			  h->s->nr_data) == h->s->nr_data)
1383 		ec_stripe_set_pending(c, h);
1384 
1385 	mutex_unlock(&h->lock);
1386 }
1387 
1388 static struct ec_stripe_head *
1389 __bch2_ec_stripe_head_get(struct btree_trans *trans,
1390 			  unsigned target,
1391 			  unsigned algo,
1392 			  unsigned redundancy,
1393 			  enum bch_watermark watermark)
1394 {
1395 	struct bch_fs *c = trans->c;
1396 	struct ec_stripe_head *h;
1397 	int ret;
1398 
1399 	if (!redundancy)
1400 		return NULL;
1401 
1402 	ret = bch2_trans_mutex_lock(trans, &c->ec_stripe_head_lock);
1403 	if (ret)
1404 		return ERR_PTR(ret);
1405 
1406 	if (test_bit(BCH_FS_GOING_RO, &c->flags)) {
1407 		h = ERR_PTR(-BCH_ERR_erofs_no_writes);
1408 		goto found;
1409 	}
1410 
1411 	list_for_each_entry(h, &c->ec_stripe_head_list, list)
1412 		if (h->target		== target &&
1413 		    h->algo		== algo &&
1414 		    h->redundancy	== redundancy &&
1415 		    h->watermark	== watermark) {
1416 			ret = bch2_trans_mutex_lock(trans, &h->lock);
1417 			if (ret)
1418 				h = ERR_PTR(ret);
1419 			goto found;
1420 		}
1421 
1422 	h = ec_new_stripe_head_alloc(c, target, algo, redundancy, watermark);
1423 found:
1424 	mutex_unlock(&c->ec_stripe_head_lock);
1425 	return h;
1426 }
1427 
1428 static int new_stripe_alloc_buckets(struct btree_trans *trans, struct ec_stripe_head *h,
1429 				    enum bch_watermark watermark, struct closure *cl)
1430 {
1431 	struct bch_fs *c = trans->c;
1432 	struct bch_devs_mask devs = h->devs;
1433 	struct open_bucket *ob;
1434 	struct open_buckets buckets;
1435 	struct bch_stripe *v = &bkey_i_to_stripe(&h->s->new_stripe.key)->v;
1436 	unsigned i, j, nr_have_parity = 0, nr_have_data = 0;
1437 	bool have_cache = true;
1438 	int ret = 0;
1439 
1440 	BUG_ON(v->nr_blocks	!= h->s->nr_data + h->s->nr_parity);
1441 	BUG_ON(v->nr_redundant	!= h->s->nr_parity);
1442 
1443 	for_each_set_bit(i, h->s->blocks_gotten, v->nr_blocks) {
1444 		__clear_bit(v->ptrs[i].dev, devs.d);
1445 		if (i < h->s->nr_data)
1446 			nr_have_data++;
1447 		else
1448 			nr_have_parity++;
1449 	}
1450 
1451 	BUG_ON(nr_have_data	> h->s->nr_data);
1452 	BUG_ON(nr_have_parity	> h->s->nr_parity);
1453 
1454 	buckets.nr = 0;
1455 	if (nr_have_parity < h->s->nr_parity) {
1456 		ret = bch2_bucket_alloc_set_trans(trans, &buckets,
1457 					    &h->parity_stripe,
1458 					    &devs,
1459 					    h->s->nr_parity,
1460 					    &nr_have_parity,
1461 					    &have_cache, 0,
1462 					    BCH_DATA_parity,
1463 					    watermark,
1464 					    cl);
1465 
1466 		open_bucket_for_each(c, &buckets, ob, i) {
1467 			j = find_next_zero_bit(h->s->blocks_gotten,
1468 					       h->s->nr_data + h->s->nr_parity,
1469 					       h->s->nr_data);
1470 			BUG_ON(j >= h->s->nr_data + h->s->nr_parity);
1471 
1472 			h->s->blocks[j] = buckets.v[i];
1473 			v->ptrs[j] = bch2_ob_ptr(c, ob);
1474 			__set_bit(j, h->s->blocks_gotten);
1475 		}
1476 
1477 		if (ret)
1478 			return ret;
1479 	}
1480 
1481 	buckets.nr = 0;
1482 	if (nr_have_data < h->s->nr_data) {
1483 		ret = bch2_bucket_alloc_set_trans(trans, &buckets,
1484 					    &h->block_stripe,
1485 					    &devs,
1486 					    h->s->nr_data,
1487 					    &nr_have_data,
1488 					    &have_cache, 0,
1489 					    BCH_DATA_user,
1490 					    watermark,
1491 					    cl);
1492 
1493 		open_bucket_for_each(c, &buckets, ob, i) {
1494 			j = find_next_zero_bit(h->s->blocks_gotten,
1495 					       h->s->nr_data, 0);
1496 			BUG_ON(j >= h->s->nr_data);
1497 
1498 			h->s->blocks[j] = buckets.v[i];
1499 			v->ptrs[j] = bch2_ob_ptr(c, ob);
1500 			__set_bit(j, h->s->blocks_gotten);
1501 		}
1502 
1503 		if (ret)
1504 			return ret;
1505 	}
1506 
1507 	return 0;
1508 }
1509 
1510 /* XXX: doesn't obey target: */
1511 static s64 get_existing_stripe(struct bch_fs *c,
1512 			       struct ec_stripe_head *head)
1513 {
1514 	ec_stripes_heap *h = &c->ec_stripes_heap;
1515 	struct stripe *m;
1516 	size_t heap_idx;
1517 	u64 stripe_idx;
1518 	s64 ret = -1;
1519 
1520 	if (may_create_new_stripe(c))
1521 		return -1;
1522 
1523 	mutex_lock(&c->ec_stripes_heap_lock);
1524 	for (heap_idx = 0; heap_idx < h->used; heap_idx++) {
1525 		/* No blocks worth reusing, stripe will just be deleted: */
1526 		if (!h->data[heap_idx].blocks_nonempty)
1527 			continue;
1528 
1529 		stripe_idx = h->data[heap_idx].idx;
1530 
1531 		m = genradix_ptr(&c->stripes, stripe_idx);
1532 
1533 		if (m->algorithm	== head->algo &&
1534 		    m->nr_redundant	== head->redundancy &&
1535 		    m->sectors		== head->blocksize &&
1536 		    m->blocks_nonempty	< m->nr_blocks - m->nr_redundant &&
1537 		    bch2_try_open_stripe(c, head->s, stripe_idx)) {
1538 			ret = stripe_idx;
1539 			break;
1540 		}
1541 	}
1542 	mutex_unlock(&c->ec_stripes_heap_lock);
1543 	return ret;
1544 }
1545 
1546 static int __bch2_ec_stripe_head_reuse(struct btree_trans *trans, struct ec_stripe_head *h)
1547 {
1548 	struct bch_fs *c = trans->c;
1549 	struct bch_stripe *new_v = &bkey_i_to_stripe(&h->s->new_stripe.key)->v;
1550 	struct bch_stripe *existing_v;
1551 	unsigned i;
1552 	s64 idx;
1553 	int ret;
1554 
1555 	/*
1556 	 * If we can't allocate a new stripe, and there's no stripes with empty
1557 	 * blocks for us to reuse, that means we have to wait on copygc:
1558 	 */
1559 	idx = get_existing_stripe(c, h);
1560 	if (idx < 0)
1561 		return -BCH_ERR_stripe_alloc_blocked;
1562 
1563 	ret = get_stripe_key_trans(trans, idx, &h->s->existing_stripe);
1564 	if (ret) {
1565 		bch2_stripe_close(c, h->s);
1566 		if (!bch2_err_matches(ret, BCH_ERR_transaction_restart))
1567 			bch2_fs_fatal_error(c, "error reading stripe key: %s", bch2_err_str(ret));
1568 		return ret;
1569 	}
1570 
1571 	existing_v = &bkey_i_to_stripe(&h->s->existing_stripe.key)->v;
1572 
1573 	BUG_ON(existing_v->nr_redundant != h->s->nr_parity);
1574 	h->s->nr_data = existing_v->nr_blocks -
1575 		existing_v->nr_redundant;
1576 
1577 	ret = ec_stripe_buf_init(&h->s->existing_stripe, 0, h->blocksize);
1578 	if (ret) {
1579 		bch2_stripe_close(c, h->s);
1580 		return ret;
1581 	}
1582 
1583 	BUG_ON(h->s->existing_stripe.size != h->blocksize);
1584 	BUG_ON(h->s->existing_stripe.size != le16_to_cpu(existing_v->sectors));
1585 
1586 	/*
1587 	 * Free buckets we initially allocated - they might conflict with
1588 	 * blocks from the stripe we're reusing:
1589 	 */
1590 	for_each_set_bit(i, h->s->blocks_gotten, new_v->nr_blocks) {
1591 		bch2_open_bucket_put(c, c->open_buckets + h->s->blocks[i]);
1592 		h->s->blocks[i] = 0;
1593 	}
1594 	memset(h->s->blocks_gotten, 0, sizeof(h->s->blocks_gotten));
1595 	memset(h->s->blocks_allocated, 0, sizeof(h->s->blocks_allocated));
1596 
1597 	for (i = 0; i < existing_v->nr_blocks; i++) {
1598 		if (stripe_blockcount_get(existing_v, i)) {
1599 			__set_bit(i, h->s->blocks_gotten);
1600 			__set_bit(i, h->s->blocks_allocated);
1601 		}
1602 
1603 		ec_block_io(c, &h->s->existing_stripe, READ, i, &h->s->iodone);
1604 	}
1605 
1606 	bkey_copy(&h->s->new_stripe.key, &h->s->existing_stripe.key);
1607 	h->s->have_existing_stripe = true;
1608 
1609 	return 0;
1610 }
1611 
1612 static int __bch2_ec_stripe_head_reserve(struct btree_trans *trans, struct ec_stripe_head *h)
1613 {
1614 	struct bch_fs *c = trans->c;
1615 	struct btree_iter iter;
1616 	struct bkey_s_c k;
1617 	struct bpos min_pos = POS(0, 1);
1618 	struct bpos start_pos = bpos_max(min_pos, POS(0, c->ec_stripe_hint));
1619 	int ret;
1620 
1621 	if (!h->s->res.sectors) {
1622 		ret = bch2_disk_reservation_get(c, &h->s->res,
1623 					h->blocksize,
1624 					h->s->nr_parity,
1625 					BCH_DISK_RESERVATION_NOFAIL);
1626 		if (ret)
1627 			return ret;
1628 	}
1629 
1630 	for_each_btree_key_norestart(trans, iter, BTREE_ID_stripes, start_pos,
1631 			   BTREE_ITER_SLOTS|BTREE_ITER_INTENT, k, ret) {
1632 		if (bkey_gt(k.k->p, POS(0, U32_MAX))) {
1633 			if (start_pos.offset) {
1634 				start_pos = min_pos;
1635 				bch2_btree_iter_set_pos(&iter, start_pos);
1636 				continue;
1637 			}
1638 
1639 			ret = -BCH_ERR_ENOSPC_stripe_create;
1640 			break;
1641 		}
1642 
1643 		if (bkey_deleted(k.k) &&
1644 		    bch2_try_open_stripe(c, h->s, k.k->p.offset))
1645 			break;
1646 	}
1647 
1648 	c->ec_stripe_hint = iter.pos.offset;
1649 
1650 	if (ret)
1651 		goto err;
1652 
1653 	ret = ec_stripe_mem_alloc(trans, &iter);
1654 	if (ret) {
1655 		bch2_stripe_close(c, h->s);
1656 		goto err;
1657 	}
1658 
1659 	h->s->new_stripe.key.k.p = iter.pos;
1660 out:
1661 	bch2_trans_iter_exit(trans, &iter);
1662 	return ret;
1663 err:
1664 	bch2_disk_reservation_put(c, &h->s->res);
1665 	goto out;
1666 }
1667 
1668 struct ec_stripe_head *bch2_ec_stripe_head_get(struct btree_trans *trans,
1669 					       unsigned target,
1670 					       unsigned algo,
1671 					       unsigned redundancy,
1672 					       enum bch_watermark watermark,
1673 					       struct closure *cl)
1674 {
1675 	struct bch_fs *c = trans->c;
1676 	struct ec_stripe_head *h;
1677 	bool waiting = false;
1678 	int ret;
1679 
1680 	h = __bch2_ec_stripe_head_get(trans, target, algo, redundancy, watermark);
1681 	if (!h)
1682 		bch_err(c, "no stripe head");
1683 	if (IS_ERR_OR_NULL(h))
1684 		return h;
1685 
1686 	if (!h->s) {
1687 		ret = ec_new_stripe_alloc(c, h);
1688 		if (ret) {
1689 			bch_err(c, "failed to allocate new stripe");
1690 			goto err;
1691 		}
1692 	}
1693 
1694 	if (h->s->allocated)
1695 		goto allocated;
1696 
1697 	if (h->s->have_existing_stripe)
1698 		goto alloc_existing;
1699 
1700 	/* First, try to allocate a full stripe: */
1701 	ret =   new_stripe_alloc_buckets(trans, h, BCH_WATERMARK_stripe, NULL) ?:
1702 		__bch2_ec_stripe_head_reserve(trans, h);
1703 	if (!ret)
1704 		goto allocate_buf;
1705 	if (bch2_err_matches(ret, BCH_ERR_transaction_restart) ||
1706 	    bch2_err_matches(ret, ENOMEM))
1707 		goto err;
1708 
1709 	/*
1710 	 * Not enough buckets available for a full stripe: we must reuse an
1711 	 * existing stripe:
1712 	 */
1713 	while (1) {
1714 		ret = __bch2_ec_stripe_head_reuse(trans, h);
1715 		if (!ret)
1716 			break;
1717 		if (waiting || !cl || ret != -BCH_ERR_stripe_alloc_blocked)
1718 			goto err;
1719 
1720 		if (watermark == BCH_WATERMARK_copygc) {
1721 			ret =   new_stripe_alloc_buckets(trans, h, watermark, NULL) ?:
1722 				__bch2_ec_stripe_head_reserve(trans, h);
1723 			if (ret)
1724 				goto err;
1725 			goto allocate_buf;
1726 		}
1727 
1728 		/* XXX freelist_wait? */
1729 		closure_wait(&c->freelist_wait, cl);
1730 		waiting = true;
1731 	}
1732 
1733 	if (waiting)
1734 		closure_wake_up(&c->freelist_wait);
1735 alloc_existing:
1736 	/*
1737 	 * Retry allocating buckets, with the watermark for this
1738 	 * particular write:
1739 	 */
1740 	ret = new_stripe_alloc_buckets(trans, h, watermark, cl);
1741 	if (ret)
1742 		goto err;
1743 
1744 allocate_buf:
1745 	ret = ec_stripe_buf_init(&h->s->new_stripe, 0, h->blocksize);
1746 	if (ret)
1747 		goto err;
1748 
1749 	h->s->allocated = true;
1750 allocated:
1751 	BUG_ON(!h->s->idx);
1752 	BUG_ON(!h->s->new_stripe.data[0]);
1753 	BUG_ON(trans->restarted);
1754 	return h;
1755 err:
1756 	bch2_ec_stripe_head_put(c, h);
1757 	return ERR_PTR(ret);
1758 }
1759 
1760 static void __bch2_ec_stop(struct bch_fs *c, struct bch_dev *ca)
1761 {
1762 	struct ec_stripe_head *h;
1763 	struct open_bucket *ob;
1764 	unsigned i;
1765 
1766 	mutex_lock(&c->ec_stripe_head_lock);
1767 	list_for_each_entry(h, &c->ec_stripe_head_list, list) {
1768 		mutex_lock(&h->lock);
1769 		if (!h->s)
1770 			goto unlock;
1771 
1772 		if (!ca)
1773 			goto found;
1774 
1775 		for (i = 0; i < bkey_i_to_stripe(&h->s->new_stripe.key)->v.nr_blocks; i++) {
1776 			if (!h->s->blocks[i])
1777 				continue;
1778 
1779 			ob = c->open_buckets + h->s->blocks[i];
1780 			if (ob->dev == ca->dev_idx)
1781 				goto found;
1782 		}
1783 		goto unlock;
1784 found:
1785 		h->s->err = -BCH_ERR_erofs_no_writes;
1786 		ec_stripe_set_pending(c, h);
1787 unlock:
1788 		mutex_unlock(&h->lock);
1789 	}
1790 	mutex_unlock(&c->ec_stripe_head_lock);
1791 }
1792 
1793 void bch2_ec_stop_dev(struct bch_fs *c, struct bch_dev *ca)
1794 {
1795 	__bch2_ec_stop(c, ca);
1796 }
1797 
1798 void bch2_fs_ec_stop(struct bch_fs *c)
1799 {
1800 	__bch2_ec_stop(c, NULL);
1801 }
1802 
1803 static bool bch2_fs_ec_flush_done(struct bch_fs *c)
1804 {
1805 	bool ret;
1806 
1807 	mutex_lock(&c->ec_stripe_new_lock);
1808 	ret = list_empty(&c->ec_stripe_new_list);
1809 	mutex_unlock(&c->ec_stripe_new_lock);
1810 
1811 	return ret;
1812 }
1813 
1814 void bch2_fs_ec_flush(struct bch_fs *c)
1815 {
1816 	wait_event(c->ec_stripe_new_wait, bch2_fs_ec_flush_done(c));
1817 }
1818 
1819 int bch2_stripes_read(struct bch_fs *c)
1820 {
1821 	struct btree_trans *trans = bch2_trans_get(c);
1822 	struct btree_iter iter;
1823 	struct bkey_s_c k;
1824 	const struct bch_stripe *s;
1825 	struct stripe *m;
1826 	unsigned i;
1827 	int ret;
1828 
1829 	for_each_btree_key(trans, iter, BTREE_ID_stripes, POS_MIN,
1830 			   BTREE_ITER_PREFETCH, k, ret) {
1831 		if (k.k->type != KEY_TYPE_stripe)
1832 			continue;
1833 
1834 		ret = __ec_stripe_mem_alloc(c, k.k->p.offset, GFP_KERNEL);
1835 		if (ret)
1836 			break;
1837 
1838 		s = bkey_s_c_to_stripe(k).v;
1839 
1840 		m = genradix_ptr(&c->stripes, k.k->p.offset);
1841 		m->sectors	= le16_to_cpu(s->sectors);
1842 		m->algorithm	= s->algorithm;
1843 		m->nr_blocks	= s->nr_blocks;
1844 		m->nr_redundant	= s->nr_redundant;
1845 		m->blocks_nonempty = 0;
1846 
1847 		for (i = 0; i < s->nr_blocks; i++)
1848 			m->blocks_nonempty += !!stripe_blockcount_get(s, i);
1849 
1850 		bch2_stripes_heap_insert(c, m, k.k->p.offset);
1851 	}
1852 	bch2_trans_iter_exit(trans, &iter);
1853 
1854 	bch2_trans_put(trans);
1855 
1856 	if (ret)
1857 		bch_err_fn(c, ret);
1858 
1859 	return ret;
1860 }
1861 
1862 void bch2_stripes_heap_to_text(struct printbuf *out, struct bch_fs *c)
1863 {
1864 	ec_stripes_heap *h = &c->ec_stripes_heap;
1865 	struct stripe *m;
1866 	size_t i;
1867 
1868 	mutex_lock(&c->ec_stripes_heap_lock);
1869 	for (i = 0; i < min_t(size_t, h->used, 50); i++) {
1870 		m = genradix_ptr(&c->stripes, h->data[i].idx);
1871 
1872 		prt_printf(out, "%zu %u/%u+%u", h->data[i].idx,
1873 		       h->data[i].blocks_nonempty,
1874 		       m->nr_blocks - m->nr_redundant,
1875 		       m->nr_redundant);
1876 		if (bch2_stripe_is_open(c, h->data[i].idx))
1877 			prt_str(out, " open");
1878 		prt_newline(out);
1879 	}
1880 	mutex_unlock(&c->ec_stripes_heap_lock);
1881 }
1882 
1883 void bch2_new_stripes_to_text(struct printbuf *out, struct bch_fs *c)
1884 {
1885 	struct ec_stripe_head *h;
1886 	struct ec_stripe_new *s;
1887 
1888 	mutex_lock(&c->ec_stripe_head_lock);
1889 	list_for_each_entry(h, &c->ec_stripe_head_list, list) {
1890 		prt_printf(out, "target %u algo %u redundancy %u %s:\n",
1891 		       h->target, h->algo, h->redundancy,
1892 		       bch2_watermarks[h->watermark]);
1893 
1894 		if (h->s)
1895 			prt_printf(out, "\tidx %llu blocks %u+%u allocated %u\n",
1896 			       h->s->idx, h->s->nr_data, h->s->nr_parity,
1897 			       bitmap_weight(h->s->blocks_allocated,
1898 					     h->s->nr_data));
1899 	}
1900 	mutex_unlock(&c->ec_stripe_head_lock);
1901 
1902 	prt_printf(out, "in flight:\n");
1903 
1904 	mutex_lock(&c->ec_stripe_new_lock);
1905 	list_for_each_entry(s, &c->ec_stripe_new_list, list) {
1906 		prt_printf(out, "\tidx %llu blocks %u+%u ref %u %u %s\n",
1907 			   s->idx, s->nr_data, s->nr_parity,
1908 			   atomic_read(&s->ref[STRIPE_REF_io]),
1909 			   atomic_read(&s->ref[STRIPE_REF_stripe]),
1910 			   bch2_watermarks[s->h->watermark]);
1911 	}
1912 	mutex_unlock(&c->ec_stripe_new_lock);
1913 }
1914 
1915 void bch2_fs_ec_exit(struct bch_fs *c)
1916 {
1917 	struct ec_stripe_head *h;
1918 	unsigned i;
1919 
1920 	while (1) {
1921 		mutex_lock(&c->ec_stripe_head_lock);
1922 		h = list_first_entry_or_null(&c->ec_stripe_head_list,
1923 					     struct ec_stripe_head, list);
1924 		if (h)
1925 			list_del(&h->list);
1926 		mutex_unlock(&c->ec_stripe_head_lock);
1927 		if (!h)
1928 			break;
1929 
1930 		if (h->s) {
1931 			for (i = 0; i < bkey_i_to_stripe(&h->s->new_stripe.key)->v.nr_blocks; i++)
1932 				BUG_ON(h->s->blocks[i]);
1933 
1934 			kfree(h->s);
1935 		}
1936 		kfree(h);
1937 	}
1938 
1939 	BUG_ON(!list_empty(&c->ec_stripe_new_list));
1940 
1941 	free_heap(&c->ec_stripes_heap);
1942 	genradix_free(&c->stripes);
1943 	bioset_exit(&c->ec_bioset);
1944 }
1945 
1946 void bch2_fs_ec_init_early(struct bch_fs *c)
1947 {
1948 	spin_lock_init(&c->ec_stripes_new_lock);
1949 	mutex_init(&c->ec_stripes_heap_lock);
1950 
1951 	INIT_LIST_HEAD(&c->ec_stripe_head_list);
1952 	mutex_init(&c->ec_stripe_head_lock);
1953 
1954 	INIT_LIST_HEAD(&c->ec_stripe_new_list);
1955 	mutex_init(&c->ec_stripe_new_lock);
1956 	init_waitqueue_head(&c->ec_stripe_new_wait);
1957 
1958 	INIT_WORK(&c->ec_stripe_create_work, ec_stripe_create_work);
1959 	INIT_WORK(&c->ec_stripe_delete_work, ec_stripe_delete_work);
1960 }
1961 
1962 int bch2_fs_ec_init(struct bch_fs *c)
1963 {
1964 	return bioset_init(&c->ec_bioset, 1, offsetof(struct ec_bio, bio),
1965 			   BIOSET_NEED_BVECS);
1966 }
1967