xref: /linux/fs/bcachefs/extents.c (revision c532de5a67a70f8533d495f8f2aaa9a0491c3ad0)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) 2010 Kent Overstreet <kent.overstreet@gmail.com>
4  *
5  * Code for managing the extent btree and dynamically updating the writeback
6  * dirty sector count.
7  */
8 
9 #include "bcachefs.h"
10 #include "bkey_methods.h"
11 #include "btree_cache.h"
12 #include "btree_gc.h"
13 #include "btree_io.h"
14 #include "btree_iter.h"
15 #include "buckets.h"
16 #include "checksum.h"
17 #include "compress.h"
18 #include "debug.h"
19 #include "disk_groups.h"
20 #include "error.h"
21 #include "extents.h"
22 #include "inode.h"
23 #include "journal.h"
24 #include "replicas.h"
25 #include "super.h"
26 #include "super-io.h"
27 #include "trace.h"
28 #include "util.h"
29 
30 static unsigned bch2_crc_field_size_max[] = {
31 	[BCH_EXTENT_ENTRY_crc32] = CRC32_SIZE_MAX,
32 	[BCH_EXTENT_ENTRY_crc64] = CRC64_SIZE_MAX,
33 	[BCH_EXTENT_ENTRY_crc128] = CRC128_SIZE_MAX,
34 };
35 
36 static void bch2_extent_crc_pack(union bch_extent_crc *,
37 				 struct bch_extent_crc_unpacked,
38 				 enum bch_extent_entry_type);
39 
40 struct bch_dev_io_failures *bch2_dev_io_failures(struct bch_io_failures *f,
41 						 unsigned dev)
42 {
43 	struct bch_dev_io_failures *i;
44 
45 	for (i = f->devs; i < f->devs + f->nr; i++)
46 		if (i->dev == dev)
47 			return i;
48 
49 	return NULL;
50 }
51 
52 void bch2_mark_io_failure(struct bch_io_failures *failed,
53 			  struct extent_ptr_decoded *p)
54 {
55 	struct bch_dev_io_failures *f = bch2_dev_io_failures(failed, p->ptr.dev);
56 
57 	if (!f) {
58 		BUG_ON(failed->nr >= ARRAY_SIZE(failed->devs));
59 
60 		f = &failed->devs[failed->nr++];
61 		f->dev		= p->ptr.dev;
62 		f->idx		= p->idx;
63 		f->nr_failed	= 1;
64 		f->nr_retries	= 0;
65 	} else if (p->idx != f->idx) {
66 		f->idx		= p->idx;
67 		f->nr_failed	= 1;
68 		f->nr_retries	= 0;
69 	} else {
70 		f->nr_failed++;
71 	}
72 }
73 
74 static inline u64 dev_latency(struct bch_fs *c, unsigned dev)
75 {
76 	struct bch_dev *ca = bch2_dev_rcu(c, dev);
77 	return ca ? atomic64_read(&ca->cur_latency[READ]) : S64_MAX;
78 }
79 
80 /*
81  * returns true if p1 is better than p2:
82  */
83 static inline bool ptr_better(struct bch_fs *c,
84 			      const struct extent_ptr_decoded p1,
85 			      const struct extent_ptr_decoded p2)
86 {
87 	if (likely(!p1.idx && !p2.idx)) {
88 		u64 l1 = dev_latency(c, p1.ptr.dev);
89 		u64 l2 = dev_latency(c, p2.ptr.dev);
90 
91 		/* Pick at random, biased in favor of the faster device: */
92 
93 		return bch2_rand_range(l1 + l2) > l1;
94 	}
95 
96 	if (bch2_force_reconstruct_read)
97 		return p1.idx > p2.idx;
98 
99 	return p1.idx < p2.idx;
100 }
101 
102 /*
103  * This picks a non-stale pointer, preferably from a device other than @avoid.
104  * Avoid can be NULL, meaning pick any. If there are no non-stale pointers to
105  * other devices, it will still pick a pointer from avoid.
106  */
107 int bch2_bkey_pick_read_device(struct bch_fs *c, struct bkey_s_c k,
108 			       struct bch_io_failures *failed,
109 			       struct extent_ptr_decoded *pick)
110 {
111 	struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
112 	const union bch_extent_entry *entry;
113 	struct extent_ptr_decoded p;
114 	struct bch_dev_io_failures *f;
115 	int ret = 0;
116 
117 	if (k.k->type == KEY_TYPE_error)
118 		return -BCH_ERR_key_type_error;
119 
120 	rcu_read_lock();
121 	bkey_for_each_ptr_decode(k.k, ptrs, p, entry) {
122 		/*
123 		 * Unwritten extent: no need to actually read, treat it as a
124 		 * hole and return 0s:
125 		 */
126 		if (p.ptr.unwritten) {
127 			ret = 0;
128 			break;
129 		}
130 
131 		/*
132 		 * If there are any dirty pointers it's an error if we can't
133 		 * read:
134 		 */
135 		if (!ret && !p.ptr.cached)
136 			ret = -BCH_ERR_no_device_to_read_from;
137 
138 		struct bch_dev *ca = bch2_dev_rcu(c, p.ptr.dev);
139 
140 		if (p.ptr.cached && (!ca || dev_ptr_stale_rcu(ca, &p.ptr)))
141 			continue;
142 
143 		f = failed ? bch2_dev_io_failures(failed, p.ptr.dev) : NULL;
144 		if (f)
145 			p.idx = f->nr_failed < f->nr_retries
146 				? f->idx
147 				: f->idx + 1;
148 
149 		if (!p.idx && (!ca || !bch2_dev_is_readable(ca)))
150 			p.idx++;
151 
152 		if (!p.idx && p.has_ec && bch2_force_reconstruct_read)
153 			p.idx++;
154 
155 		if (p.idx > (unsigned) p.has_ec)
156 			continue;
157 
158 		if (ret > 0 && !ptr_better(c, p, *pick))
159 			continue;
160 
161 		*pick = p;
162 		ret = 1;
163 	}
164 	rcu_read_unlock();
165 
166 	return ret;
167 }
168 
169 /* KEY_TYPE_btree_ptr: */
170 
171 int bch2_btree_ptr_validate(struct bch_fs *c, struct bkey_s_c k,
172 			    enum bch_validate_flags flags)
173 {
174 	int ret = 0;
175 
176 	bkey_fsck_err_on(bkey_val_u64s(k.k) > BCH_REPLICAS_MAX,
177 			 c, btree_ptr_val_too_big,
178 			 "value too big (%zu > %u)", bkey_val_u64s(k.k), BCH_REPLICAS_MAX);
179 
180 	ret = bch2_bkey_ptrs_validate(c, k, flags);
181 fsck_err:
182 	return ret;
183 }
184 
185 void bch2_btree_ptr_to_text(struct printbuf *out, struct bch_fs *c,
186 			    struct bkey_s_c k)
187 {
188 	bch2_bkey_ptrs_to_text(out, c, k);
189 }
190 
191 int bch2_btree_ptr_v2_validate(struct bch_fs *c, struct bkey_s_c k,
192 			       enum bch_validate_flags flags)
193 {
194 	struct bkey_s_c_btree_ptr_v2 bp = bkey_s_c_to_btree_ptr_v2(k);
195 	int ret = 0;
196 
197 	bkey_fsck_err_on(bkey_val_u64s(k.k) > BKEY_BTREE_PTR_VAL_U64s_MAX,
198 			 c, btree_ptr_v2_val_too_big,
199 			 "value too big (%zu > %zu)",
200 			 bkey_val_u64s(k.k), BKEY_BTREE_PTR_VAL_U64s_MAX);
201 
202 	bkey_fsck_err_on(bpos_ge(bp.v->min_key, bp.k->p),
203 			 c, btree_ptr_v2_min_key_bad,
204 			 "min_key > key");
205 
206 	if (flags & BCH_VALIDATE_write)
207 		bkey_fsck_err_on(!bp.v->sectors_written,
208 				 c, btree_ptr_v2_written_0,
209 				 "sectors_written == 0");
210 
211 	ret = bch2_bkey_ptrs_validate(c, k, flags);
212 fsck_err:
213 	return ret;
214 }
215 
216 void bch2_btree_ptr_v2_to_text(struct printbuf *out, struct bch_fs *c,
217 			       struct bkey_s_c k)
218 {
219 	struct bkey_s_c_btree_ptr_v2 bp = bkey_s_c_to_btree_ptr_v2(k);
220 
221 	prt_printf(out, "seq %llx written %u min_key %s",
222 	       le64_to_cpu(bp.v->seq),
223 	       le16_to_cpu(bp.v->sectors_written),
224 	       BTREE_PTR_RANGE_UPDATED(bp.v) ? "R " : "");
225 
226 	bch2_bpos_to_text(out, bp.v->min_key);
227 	prt_printf(out, " ");
228 	bch2_bkey_ptrs_to_text(out, c, k);
229 }
230 
231 void bch2_btree_ptr_v2_compat(enum btree_id btree_id, unsigned version,
232 			      unsigned big_endian, int write,
233 			      struct bkey_s k)
234 {
235 	struct bkey_s_btree_ptr_v2 bp = bkey_s_to_btree_ptr_v2(k);
236 
237 	compat_bpos(0, btree_id, version, big_endian, write, &bp.v->min_key);
238 
239 	if (version < bcachefs_metadata_version_inode_btree_change &&
240 	    btree_id_is_extents(btree_id) &&
241 	    !bkey_eq(bp.v->min_key, POS_MIN))
242 		bp.v->min_key = write
243 			? bpos_nosnap_predecessor(bp.v->min_key)
244 			: bpos_nosnap_successor(bp.v->min_key);
245 }
246 
247 /* KEY_TYPE_extent: */
248 
249 bool bch2_extent_merge(struct bch_fs *c, struct bkey_s l, struct bkey_s_c r)
250 {
251 	struct bkey_ptrs   l_ptrs = bch2_bkey_ptrs(l);
252 	struct bkey_ptrs_c r_ptrs = bch2_bkey_ptrs_c(r);
253 	union bch_extent_entry *en_l;
254 	const union bch_extent_entry *en_r;
255 	struct extent_ptr_decoded lp, rp;
256 	bool use_right_ptr;
257 
258 	en_l = l_ptrs.start;
259 	en_r = r_ptrs.start;
260 	while (en_l < l_ptrs.end && en_r < r_ptrs.end) {
261 		if (extent_entry_type(en_l) != extent_entry_type(en_r))
262 			return false;
263 
264 		en_l = extent_entry_next(en_l);
265 		en_r = extent_entry_next(en_r);
266 	}
267 
268 	if (en_l < l_ptrs.end || en_r < r_ptrs.end)
269 		return false;
270 
271 	en_l = l_ptrs.start;
272 	en_r = r_ptrs.start;
273 	lp.crc = bch2_extent_crc_unpack(l.k, NULL);
274 	rp.crc = bch2_extent_crc_unpack(r.k, NULL);
275 
276 	while (__bkey_ptr_next_decode(l.k, l_ptrs.end, lp, en_l) &&
277 	       __bkey_ptr_next_decode(r.k, r_ptrs.end, rp, en_r)) {
278 		if (lp.ptr.offset + lp.crc.offset + lp.crc.live_size !=
279 		    rp.ptr.offset + rp.crc.offset ||
280 		    lp.ptr.dev			!= rp.ptr.dev ||
281 		    lp.ptr.gen			!= rp.ptr.gen ||
282 		    lp.ptr.unwritten		!= rp.ptr.unwritten ||
283 		    lp.has_ec			!= rp.has_ec)
284 			return false;
285 
286 		/* Extents may not straddle buckets: */
287 		rcu_read_lock();
288 		struct bch_dev *ca = bch2_dev_rcu(c, lp.ptr.dev);
289 		bool same_bucket = ca && PTR_BUCKET_NR(ca, &lp.ptr) == PTR_BUCKET_NR(ca, &rp.ptr);
290 		rcu_read_unlock();
291 
292 		if (!same_bucket)
293 			return false;
294 
295 		if (lp.has_ec			!= rp.has_ec ||
296 		    (lp.has_ec &&
297 		     (lp.ec.block		!= rp.ec.block ||
298 		      lp.ec.redundancy		!= rp.ec.redundancy ||
299 		      lp.ec.idx			!= rp.ec.idx)))
300 			return false;
301 
302 		if (lp.crc.compression_type	!= rp.crc.compression_type ||
303 		    lp.crc.nonce		!= rp.crc.nonce)
304 			return false;
305 
306 		if (lp.crc.offset + lp.crc.live_size + rp.crc.live_size <=
307 		    lp.crc.uncompressed_size) {
308 			/* can use left extent's crc entry */
309 		} else if (lp.crc.live_size <= rp.crc.offset) {
310 			/* can use right extent's crc entry */
311 		} else {
312 			/* check if checksums can be merged: */
313 			if (lp.crc.csum_type		!= rp.crc.csum_type ||
314 			    lp.crc.nonce		!= rp.crc.nonce ||
315 			    crc_is_compressed(lp.crc) ||
316 			    !bch2_checksum_mergeable(lp.crc.csum_type))
317 				return false;
318 
319 			if (lp.crc.offset + lp.crc.live_size != lp.crc.compressed_size ||
320 			    rp.crc.offset)
321 				return false;
322 
323 			if (lp.crc.csum_type &&
324 			    lp.crc.uncompressed_size +
325 			    rp.crc.uncompressed_size > (c->opts.encoded_extent_max >> 9))
326 				return false;
327 		}
328 
329 		en_l = extent_entry_next(en_l);
330 		en_r = extent_entry_next(en_r);
331 	}
332 
333 	en_l = l_ptrs.start;
334 	en_r = r_ptrs.start;
335 	while (en_l < l_ptrs.end && en_r < r_ptrs.end) {
336 		if (extent_entry_is_crc(en_l)) {
337 			struct bch_extent_crc_unpacked crc_l = bch2_extent_crc_unpack(l.k, entry_to_crc(en_l));
338 			struct bch_extent_crc_unpacked crc_r = bch2_extent_crc_unpack(r.k, entry_to_crc(en_r));
339 
340 			if (crc_l.uncompressed_size + crc_r.uncompressed_size >
341 			    bch2_crc_field_size_max[extent_entry_type(en_l)])
342 				return false;
343 		}
344 
345 		en_l = extent_entry_next(en_l);
346 		en_r = extent_entry_next(en_r);
347 	}
348 
349 	use_right_ptr = false;
350 	en_l = l_ptrs.start;
351 	en_r = r_ptrs.start;
352 	while (en_l < l_ptrs.end) {
353 		if (extent_entry_type(en_l) == BCH_EXTENT_ENTRY_ptr &&
354 		    use_right_ptr)
355 			en_l->ptr = en_r->ptr;
356 
357 		if (extent_entry_is_crc(en_l)) {
358 			struct bch_extent_crc_unpacked crc_l =
359 				bch2_extent_crc_unpack(l.k, entry_to_crc(en_l));
360 			struct bch_extent_crc_unpacked crc_r =
361 				bch2_extent_crc_unpack(r.k, entry_to_crc(en_r));
362 
363 			use_right_ptr = false;
364 
365 			if (crc_l.offset + crc_l.live_size + crc_r.live_size <=
366 			    crc_l.uncompressed_size) {
367 				/* can use left extent's crc entry */
368 			} else if (crc_l.live_size <= crc_r.offset) {
369 				/* can use right extent's crc entry */
370 				crc_r.offset -= crc_l.live_size;
371 				bch2_extent_crc_pack(entry_to_crc(en_l), crc_r,
372 						     extent_entry_type(en_l));
373 				use_right_ptr = true;
374 			} else {
375 				crc_l.csum = bch2_checksum_merge(crc_l.csum_type,
376 								 crc_l.csum,
377 								 crc_r.csum,
378 								 crc_r.uncompressed_size << 9);
379 
380 				crc_l.uncompressed_size	+= crc_r.uncompressed_size;
381 				crc_l.compressed_size	+= crc_r.compressed_size;
382 				bch2_extent_crc_pack(entry_to_crc(en_l), crc_l,
383 						     extent_entry_type(en_l));
384 			}
385 		}
386 
387 		en_l = extent_entry_next(en_l);
388 		en_r = extent_entry_next(en_r);
389 	}
390 
391 	bch2_key_resize(l.k, l.k->size + r.k->size);
392 	return true;
393 }
394 
395 /* KEY_TYPE_reservation: */
396 
397 int bch2_reservation_validate(struct bch_fs *c, struct bkey_s_c k,
398 			      enum bch_validate_flags flags)
399 {
400 	struct bkey_s_c_reservation r = bkey_s_c_to_reservation(k);
401 	int ret = 0;
402 
403 	bkey_fsck_err_on(!r.v->nr_replicas || r.v->nr_replicas > BCH_REPLICAS_MAX,
404 			 c, reservation_key_nr_replicas_invalid,
405 			 "invalid nr_replicas (%u)", r.v->nr_replicas);
406 fsck_err:
407 	return ret;
408 }
409 
410 void bch2_reservation_to_text(struct printbuf *out, struct bch_fs *c,
411 			      struct bkey_s_c k)
412 {
413 	struct bkey_s_c_reservation r = bkey_s_c_to_reservation(k);
414 
415 	prt_printf(out, "generation %u replicas %u",
416 	       le32_to_cpu(r.v->generation),
417 	       r.v->nr_replicas);
418 }
419 
420 bool bch2_reservation_merge(struct bch_fs *c, struct bkey_s _l, struct bkey_s_c _r)
421 {
422 	struct bkey_s_reservation l = bkey_s_to_reservation(_l);
423 	struct bkey_s_c_reservation r = bkey_s_c_to_reservation(_r);
424 
425 	if (l.v->generation != r.v->generation ||
426 	    l.v->nr_replicas != r.v->nr_replicas)
427 		return false;
428 
429 	bch2_key_resize(l.k, l.k->size + r.k->size);
430 	return true;
431 }
432 
433 /* Extent checksum entries: */
434 
435 /* returns true if not equal */
436 static inline bool bch2_crc_unpacked_cmp(struct bch_extent_crc_unpacked l,
437 					 struct bch_extent_crc_unpacked r)
438 {
439 	return (l.csum_type		!= r.csum_type ||
440 		l.compression_type	!= r.compression_type ||
441 		l.compressed_size	!= r.compressed_size ||
442 		l.uncompressed_size	!= r.uncompressed_size ||
443 		l.offset		!= r.offset ||
444 		l.live_size		!= r.live_size ||
445 		l.nonce			!= r.nonce ||
446 		bch2_crc_cmp(l.csum, r.csum));
447 }
448 
449 static inline bool can_narrow_crc(struct bch_extent_crc_unpacked u,
450 				  struct bch_extent_crc_unpacked n)
451 {
452 	return !crc_is_compressed(u) &&
453 		u.csum_type &&
454 		u.uncompressed_size > u.live_size &&
455 		bch2_csum_type_is_encryption(u.csum_type) ==
456 		bch2_csum_type_is_encryption(n.csum_type);
457 }
458 
459 bool bch2_can_narrow_extent_crcs(struct bkey_s_c k,
460 				 struct bch_extent_crc_unpacked n)
461 {
462 	struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
463 	struct bch_extent_crc_unpacked crc;
464 	const union bch_extent_entry *i;
465 
466 	if (!n.csum_type)
467 		return false;
468 
469 	bkey_for_each_crc(k.k, ptrs, crc, i)
470 		if (can_narrow_crc(crc, n))
471 			return true;
472 
473 	return false;
474 }
475 
476 /*
477  * We're writing another replica for this extent, so while we've got the data in
478  * memory we'll be computing a new checksum for the currently live data.
479  *
480  * If there are other replicas we aren't moving, and they are checksummed but
481  * not compressed, we can modify them to point to only the data that is
482  * currently live (so that readers won't have to bounce) while we've got the
483  * checksum we need:
484  */
485 bool bch2_bkey_narrow_crcs(struct bkey_i *k, struct bch_extent_crc_unpacked n)
486 {
487 	struct bkey_ptrs ptrs = bch2_bkey_ptrs(bkey_i_to_s(k));
488 	struct bch_extent_crc_unpacked u;
489 	struct extent_ptr_decoded p;
490 	union bch_extent_entry *i;
491 	bool ret = false;
492 
493 	/* Find a checksum entry that covers only live data: */
494 	if (!n.csum_type) {
495 		bkey_for_each_crc(&k->k, ptrs, u, i)
496 			if (!crc_is_compressed(u) &&
497 			    u.csum_type &&
498 			    u.live_size == u.uncompressed_size) {
499 				n = u;
500 				goto found;
501 			}
502 		return false;
503 	}
504 found:
505 	BUG_ON(crc_is_compressed(n));
506 	BUG_ON(n.offset);
507 	BUG_ON(n.live_size != k->k.size);
508 
509 restart_narrow_pointers:
510 	ptrs = bch2_bkey_ptrs(bkey_i_to_s(k));
511 
512 	bkey_for_each_ptr_decode(&k->k, ptrs, p, i)
513 		if (can_narrow_crc(p.crc, n)) {
514 			bch2_bkey_drop_ptr_noerror(bkey_i_to_s(k), &i->ptr);
515 			p.ptr.offset += p.crc.offset;
516 			p.crc = n;
517 			bch2_extent_ptr_decoded_append(k, &p);
518 			ret = true;
519 			goto restart_narrow_pointers;
520 		}
521 
522 	return ret;
523 }
524 
525 static void bch2_extent_crc_pack(union bch_extent_crc *dst,
526 				 struct bch_extent_crc_unpacked src,
527 				 enum bch_extent_entry_type type)
528 {
529 #define set_common_fields(_dst, _src)					\
530 		_dst.type		= 1 << type;			\
531 		_dst.csum_type		= _src.csum_type,		\
532 		_dst.compression_type	= _src.compression_type,	\
533 		_dst._compressed_size	= _src.compressed_size - 1,	\
534 		_dst._uncompressed_size	= _src.uncompressed_size - 1,	\
535 		_dst.offset		= _src.offset
536 
537 	switch (type) {
538 	case BCH_EXTENT_ENTRY_crc32:
539 		set_common_fields(dst->crc32, src);
540 		dst->crc32.csum		= (u32 __force) *((__le32 *) &src.csum.lo);
541 		break;
542 	case BCH_EXTENT_ENTRY_crc64:
543 		set_common_fields(dst->crc64, src);
544 		dst->crc64.nonce	= src.nonce;
545 		dst->crc64.csum_lo	= (u64 __force) src.csum.lo;
546 		dst->crc64.csum_hi	= (u64 __force) *((__le16 *) &src.csum.hi);
547 		break;
548 	case BCH_EXTENT_ENTRY_crc128:
549 		set_common_fields(dst->crc128, src);
550 		dst->crc128.nonce	= src.nonce;
551 		dst->crc128.csum	= src.csum;
552 		break;
553 	default:
554 		BUG();
555 	}
556 #undef set_common_fields
557 }
558 
559 void bch2_extent_crc_append(struct bkey_i *k,
560 			    struct bch_extent_crc_unpacked new)
561 {
562 	struct bkey_ptrs ptrs = bch2_bkey_ptrs(bkey_i_to_s(k));
563 	union bch_extent_crc *crc = (void *) ptrs.end;
564 	enum bch_extent_entry_type type;
565 
566 	if (bch_crc_bytes[new.csum_type]	<= 4 &&
567 	    new.uncompressed_size		<= CRC32_SIZE_MAX &&
568 	    new.nonce				<= CRC32_NONCE_MAX)
569 		type = BCH_EXTENT_ENTRY_crc32;
570 	else if (bch_crc_bytes[new.csum_type]	<= 10 &&
571 		   new.uncompressed_size	<= CRC64_SIZE_MAX &&
572 		   new.nonce			<= CRC64_NONCE_MAX)
573 		type = BCH_EXTENT_ENTRY_crc64;
574 	else if (bch_crc_bytes[new.csum_type]	<= 16 &&
575 		   new.uncompressed_size	<= CRC128_SIZE_MAX &&
576 		   new.nonce			<= CRC128_NONCE_MAX)
577 		type = BCH_EXTENT_ENTRY_crc128;
578 	else
579 		BUG();
580 
581 	bch2_extent_crc_pack(crc, new, type);
582 
583 	k->k.u64s += extent_entry_u64s(ptrs.end);
584 
585 	EBUG_ON(bkey_val_u64s(&k->k) > BKEY_EXTENT_VAL_U64s_MAX);
586 }
587 
588 /* Generic code for keys with pointers: */
589 
590 unsigned bch2_bkey_nr_ptrs(struct bkey_s_c k)
591 {
592 	return bch2_bkey_devs(k).nr;
593 }
594 
595 unsigned bch2_bkey_nr_ptrs_allocated(struct bkey_s_c k)
596 {
597 	return k.k->type == KEY_TYPE_reservation
598 		? bkey_s_c_to_reservation(k).v->nr_replicas
599 		: bch2_bkey_dirty_devs(k).nr;
600 }
601 
602 unsigned bch2_bkey_nr_ptrs_fully_allocated(struct bkey_s_c k)
603 {
604 	unsigned ret = 0;
605 
606 	if (k.k->type == KEY_TYPE_reservation) {
607 		ret = bkey_s_c_to_reservation(k).v->nr_replicas;
608 	} else {
609 		struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
610 		const union bch_extent_entry *entry;
611 		struct extent_ptr_decoded p;
612 
613 		bkey_for_each_ptr_decode(k.k, ptrs, p, entry)
614 			ret += !p.ptr.cached && !crc_is_compressed(p.crc);
615 	}
616 
617 	return ret;
618 }
619 
620 unsigned bch2_bkey_sectors_compressed(struct bkey_s_c k)
621 {
622 	struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
623 	const union bch_extent_entry *entry;
624 	struct extent_ptr_decoded p;
625 	unsigned ret = 0;
626 
627 	bkey_for_each_ptr_decode(k.k, ptrs, p, entry)
628 		if (!p.ptr.cached && crc_is_compressed(p.crc))
629 			ret += p.crc.compressed_size;
630 
631 	return ret;
632 }
633 
634 bool bch2_bkey_is_incompressible(struct bkey_s_c k)
635 {
636 	struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
637 	const union bch_extent_entry *entry;
638 	struct bch_extent_crc_unpacked crc;
639 
640 	bkey_for_each_crc(k.k, ptrs, crc, entry)
641 		if (crc.compression_type == BCH_COMPRESSION_TYPE_incompressible)
642 			return true;
643 	return false;
644 }
645 
646 unsigned bch2_bkey_replicas(struct bch_fs *c, struct bkey_s_c k)
647 {
648 	struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
649 	const union bch_extent_entry *entry;
650 	struct extent_ptr_decoded p = { 0 };
651 	unsigned replicas = 0;
652 
653 	bkey_for_each_ptr_decode(k.k, ptrs, p, entry) {
654 		if (p.ptr.cached)
655 			continue;
656 
657 		if (p.has_ec)
658 			replicas += p.ec.redundancy;
659 
660 		replicas++;
661 
662 	}
663 
664 	return replicas;
665 }
666 
667 static inline unsigned __extent_ptr_durability(struct bch_dev *ca, struct extent_ptr_decoded *p)
668 {
669 	if (p->ptr.cached)
670 		return 0;
671 
672 	return p->has_ec
673 		? p->ec.redundancy + 1
674 		: ca->mi.durability;
675 }
676 
677 unsigned bch2_extent_ptr_desired_durability(struct bch_fs *c, struct extent_ptr_decoded *p)
678 {
679 	struct bch_dev *ca = bch2_dev_rcu(c, p->ptr.dev);
680 
681 	return ca ? __extent_ptr_durability(ca, p) : 0;
682 }
683 
684 unsigned bch2_extent_ptr_durability(struct bch_fs *c, struct extent_ptr_decoded *p)
685 {
686 	struct bch_dev *ca = bch2_dev_rcu(c, p->ptr.dev);
687 
688 	if (!ca || ca->mi.state == BCH_MEMBER_STATE_failed)
689 		return 0;
690 
691 	return __extent_ptr_durability(ca, p);
692 }
693 
694 unsigned bch2_bkey_durability(struct bch_fs *c, struct bkey_s_c k)
695 {
696 	struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
697 	const union bch_extent_entry *entry;
698 	struct extent_ptr_decoded p;
699 	unsigned durability = 0;
700 
701 	rcu_read_lock();
702 	bkey_for_each_ptr_decode(k.k, ptrs, p, entry)
703 		durability += bch2_extent_ptr_durability(c, &p);
704 	rcu_read_unlock();
705 
706 	return durability;
707 }
708 
709 static unsigned bch2_bkey_durability_safe(struct bch_fs *c, struct bkey_s_c k)
710 {
711 	struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
712 	const union bch_extent_entry *entry;
713 	struct extent_ptr_decoded p;
714 	unsigned durability = 0;
715 
716 	rcu_read_lock();
717 	bkey_for_each_ptr_decode(k.k, ptrs, p, entry)
718 		if (p.ptr.dev < c->sb.nr_devices && c->devs[p.ptr.dev])
719 			durability += bch2_extent_ptr_durability(c, &p);
720 	rcu_read_unlock();
721 
722 	return durability;
723 }
724 
725 void bch2_bkey_extent_entry_drop(struct bkey_i *k, union bch_extent_entry *entry)
726 {
727 	union bch_extent_entry *end = bkey_val_end(bkey_i_to_s(k));
728 	union bch_extent_entry *next = extent_entry_next(entry);
729 
730 	memmove_u64s(entry, next, (u64 *) end - (u64 *) next);
731 	k->k.u64s -= extent_entry_u64s(entry);
732 }
733 
734 void bch2_extent_ptr_decoded_append(struct bkey_i *k,
735 				    struct extent_ptr_decoded *p)
736 {
737 	struct bkey_ptrs ptrs = bch2_bkey_ptrs(bkey_i_to_s(k));
738 	struct bch_extent_crc_unpacked crc =
739 		bch2_extent_crc_unpack(&k->k, NULL);
740 	union bch_extent_entry *pos;
741 
742 	if (!bch2_crc_unpacked_cmp(crc, p->crc)) {
743 		pos = ptrs.start;
744 		goto found;
745 	}
746 
747 	bkey_for_each_crc(&k->k, ptrs, crc, pos)
748 		if (!bch2_crc_unpacked_cmp(crc, p->crc)) {
749 			pos = extent_entry_next(pos);
750 			goto found;
751 		}
752 
753 	bch2_extent_crc_append(k, p->crc);
754 	pos = bkey_val_end(bkey_i_to_s(k));
755 found:
756 	p->ptr.type = 1 << BCH_EXTENT_ENTRY_ptr;
757 	__extent_entry_insert(k, pos, to_entry(&p->ptr));
758 
759 	if (p->has_ec) {
760 		p->ec.type = 1 << BCH_EXTENT_ENTRY_stripe_ptr;
761 		__extent_entry_insert(k, pos, to_entry(&p->ec));
762 	}
763 }
764 
765 static union bch_extent_entry *extent_entry_prev(struct bkey_ptrs ptrs,
766 					  union bch_extent_entry *entry)
767 {
768 	union bch_extent_entry *i = ptrs.start;
769 
770 	if (i == entry)
771 		return NULL;
772 
773 	while (extent_entry_next(i) != entry)
774 		i = extent_entry_next(i);
775 	return i;
776 }
777 
778 /*
779  * Returns pointer to the next entry after the one being dropped:
780  */
781 void bch2_bkey_drop_ptr_noerror(struct bkey_s k, struct bch_extent_ptr *ptr)
782 {
783 	struct bkey_ptrs ptrs = bch2_bkey_ptrs(k);
784 	union bch_extent_entry *entry = to_entry(ptr), *next;
785 	bool drop_crc = true;
786 
787 	if (k.k->type == KEY_TYPE_stripe) {
788 		ptr->dev = BCH_SB_MEMBER_INVALID;
789 		return;
790 	}
791 
792 	EBUG_ON(ptr < &ptrs.start->ptr ||
793 		ptr >= &ptrs.end->ptr);
794 	EBUG_ON(ptr->type != 1 << BCH_EXTENT_ENTRY_ptr);
795 
796 	for (next = extent_entry_next(entry);
797 	     next != ptrs.end;
798 	     next = extent_entry_next(next)) {
799 		if (extent_entry_is_crc(next)) {
800 			break;
801 		} else if (extent_entry_is_ptr(next)) {
802 			drop_crc = false;
803 			break;
804 		}
805 	}
806 
807 	extent_entry_drop(k, entry);
808 
809 	while ((entry = extent_entry_prev(ptrs, entry))) {
810 		if (extent_entry_is_ptr(entry))
811 			break;
812 
813 		if ((extent_entry_is_crc(entry) && drop_crc) ||
814 		    extent_entry_is_stripe_ptr(entry))
815 			extent_entry_drop(k, entry);
816 	}
817 }
818 
819 void bch2_bkey_drop_ptr(struct bkey_s k, struct bch_extent_ptr *ptr)
820 {
821 	if (k.k->type != KEY_TYPE_stripe) {
822 		struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k.s_c);
823 		const union bch_extent_entry *entry;
824 		struct extent_ptr_decoded p;
825 
826 		bkey_for_each_ptr_decode(k.k, ptrs, p, entry)
827 			if (p.ptr.dev == ptr->dev && p.has_ec) {
828 				ptr->dev = BCH_SB_MEMBER_INVALID;
829 				return;
830 			}
831 	}
832 
833 	bool have_dirty = bch2_bkey_dirty_devs(k.s_c).nr;
834 
835 	bch2_bkey_drop_ptr_noerror(k, ptr);
836 
837 	/*
838 	 * If we deleted all the dirty pointers and there's still cached
839 	 * pointers, we could set the cached pointers to dirty if they're not
840 	 * stale - but to do that correctly we'd need to grab an open_bucket
841 	 * reference so that we don't race with bucket reuse:
842 	 */
843 	if (have_dirty &&
844 	    !bch2_bkey_dirty_devs(k.s_c).nr) {
845 		k.k->type = KEY_TYPE_error;
846 		set_bkey_val_u64s(k.k, 0);
847 	} else if (!bch2_bkey_nr_ptrs(k.s_c)) {
848 		k.k->type = KEY_TYPE_deleted;
849 		set_bkey_val_u64s(k.k, 0);
850 	}
851 }
852 
853 void bch2_bkey_drop_device(struct bkey_s k, unsigned dev)
854 {
855 	bch2_bkey_drop_ptrs(k, ptr, ptr->dev == dev);
856 }
857 
858 void bch2_bkey_drop_device_noerror(struct bkey_s k, unsigned dev)
859 {
860 	bch2_bkey_drop_ptrs_noerror(k, ptr, ptr->dev == dev);
861 }
862 
863 const struct bch_extent_ptr *bch2_bkey_has_device_c(struct bkey_s_c k, unsigned dev)
864 {
865 	struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
866 
867 	bkey_for_each_ptr(ptrs, ptr)
868 		if (ptr->dev == dev)
869 			return ptr;
870 
871 	return NULL;
872 }
873 
874 bool bch2_bkey_has_target(struct bch_fs *c, struct bkey_s_c k, unsigned target)
875 {
876 	struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
877 	struct bch_dev *ca;
878 	bool ret = false;
879 
880 	rcu_read_lock();
881 	bkey_for_each_ptr(ptrs, ptr)
882 		if (bch2_dev_in_target(c, ptr->dev, target) &&
883 		    (ca = bch2_dev_rcu(c, ptr->dev)) &&
884 		    (!ptr->cached ||
885 		     !dev_ptr_stale_rcu(ca, ptr))) {
886 			ret = true;
887 			break;
888 		}
889 	rcu_read_unlock();
890 
891 	return ret;
892 }
893 
894 bool bch2_bkey_matches_ptr(struct bch_fs *c, struct bkey_s_c k,
895 			   struct bch_extent_ptr m, u64 offset)
896 {
897 	struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
898 	const union bch_extent_entry *entry;
899 	struct extent_ptr_decoded p;
900 
901 	bkey_for_each_ptr_decode(k.k, ptrs, p, entry)
902 		if (p.ptr.dev	== m.dev &&
903 		    p.ptr.gen	== m.gen &&
904 		    (s64) p.ptr.offset + p.crc.offset - bkey_start_offset(k.k) ==
905 		    (s64) m.offset  - offset)
906 			return true;
907 
908 	return false;
909 }
910 
911 /*
912  * Returns true if two extents refer to the same data:
913  */
914 bool bch2_extents_match(struct bkey_s_c k1, struct bkey_s_c k2)
915 {
916 	if (k1.k->type != k2.k->type)
917 		return false;
918 
919 	if (bkey_extent_is_direct_data(k1.k)) {
920 		struct bkey_ptrs_c ptrs1 = bch2_bkey_ptrs_c(k1);
921 		struct bkey_ptrs_c ptrs2 = bch2_bkey_ptrs_c(k2);
922 		const union bch_extent_entry *entry1, *entry2;
923 		struct extent_ptr_decoded p1, p2;
924 
925 		if (bkey_extent_is_unwritten(k1) != bkey_extent_is_unwritten(k2))
926 			return false;
927 
928 		bkey_for_each_ptr_decode(k1.k, ptrs1, p1, entry1)
929 			bkey_for_each_ptr_decode(k2.k, ptrs2, p2, entry2)
930 				if (p1.ptr.dev		== p2.ptr.dev &&
931 				    p1.ptr.gen		== p2.ptr.gen &&
932 
933 				    /*
934 				     * This checks that the two pointers point
935 				     * to the same region on disk - adjusting
936 				     * for the difference in where the extents
937 				     * start, since one may have been trimmed:
938 				     */
939 				    (s64) p1.ptr.offset + p1.crc.offset - bkey_start_offset(k1.k) ==
940 				    (s64) p2.ptr.offset + p2.crc.offset - bkey_start_offset(k2.k) &&
941 
942 				    /*
943 				     * This additionally checks that the
944 				     * extents overlap on disk, since the
945 				     * previous check may trigger spuriously
946 				     * when one extent is immediately partially
947 				     * overwritten with another extent (so that
948 				     * on disk they are adjacent) and
949 				     * compression is in use:
950 				     */
951 				    ((p1.ptr.offset >= p2.ptr.offset &&
952 				      p1.ptr.offset  < p2.ptr.offset + p2.crc.compressed_size) ||
953 				     (p2.ptr.offset >= p1.ptr.offset &&
954 				      p2.ptr.offset  < p1.ptr.offset + p1.crc.compressed_size)))
955 					return true;
956 
957 		return false;
958 	} else {
959 		/* KEY_TYPE_deleted, etc. */
960 		return true;
961 	}
962 }
963 
964 struct bch_extent_ptr *
965 bch2_extent_has_ptr(struct bkey_s_c k1, struct extent_ptr_decoded p1, struct bkey_s k2)
966 {
967 	struct bkey_ptrs ptrs2 = bch2_bkey_ptrs(k2);
968 	union bch_extent_entry *entry2;
969 	struct extent_ptr_decoded p2;
970 
971 	bkey_for_each_ptr_decode(k2.k, ptrs2, p2, entry2)
972 		if (p1.ptr.dev		== p2.ptr.dev &&
973 		    p1.ptr.gen		== p2.ptr.gen &&
974 		    (s64) p1.ptr.offset + p1.crc.offset - bkey_start_offset(k1.k) ==
975 		    (s64) p2.ptr.offset + p2.crc.offset - bkey_start_offset(k2.k))
976 			return &entry2->ptr;
977 
978 	return NULL;
979 }
980 
981 static bool want_cached_ptr(struct bch_fs *c, struct bch_io_opts *opts,
982 			    struct bch_extent_ptr *ptr)
983 {
984 	if (!opts->promote_target ||
985 	    !bch2_dev_in_target(c, ptr->dev, opts->promote_target))
986 		return false;
987 
988 	struct bch_dev *ca = bch2_dev_rcu_noerror(c, ptr->dev);
989 
990 	return ca && bch2_dev_is_readable(ca) && !dev_ptr_stale_rcu(ca, ptr);
991 }
992 
993 void bch2_extent_ptr_set_cached(struct bch_fs *c,
994 				struct bch_io_opts *opts,
995 				struct bkey_s k,
996 				struct bch_extent_ptr *ptr)
997 {
998 	struct bkey_ptrs ptrs = bch2_bkey_ptrs(k);
999 	union bch_extent_entry *entry;
1000 	struct extent_ptr_decoded p;
1001 
1002 	rcu_read_lock();
1003 	if (!want_cached_ptr(c, opts, ptr)) {
1004 		bch2_bkey_drop_ptr_noerror(k, ptr);
1005 		goto out;
1006 	}
1007 
1008 	/*
1009 	 * Stripes can't contain cached data, for - reasons.
1010 	 *
1011 	 * Possibly something we can fix in the future?
1012 	 */
1013 	bkey_for_each_ptr_decode(k.k, ptrs, p, entry)
1014 		if (&entry->ptr == ptr) {
1015 			if (p.has_ec)
1016 				bch2_bkey_drop_ptr_noerror(k, ptr);
1017 			else
1018 				ptr->cached = true;
1019 			goto out;
1020 		}
1021 
1022 	BUG();
1023 out:
1024 	rcu_read_unlock();
1025 }
1026 
1027 /*
1028  * bch2_extent_normalize - clean up an extent, dropping stale pointers etc.
1029  *
1030  * Returns true if @k should be dropped entirely
1031  *
1032  * For existing keys, only called when btree nodes are being rewritten, not when
1033  * they're merely being compacted/resorted in memory.
1034  */
1035 bool bch2_extent_normalize(struct bch_fs *c, struct bkey_s k)
1036 {
1037 	struct bch_dev *ca;
1038 
1039 	rcu_read_lock();
1040 	bch2_bkey_drop_ptrs(k, ptr,
1041 		ptr->cached &&
1042 		(!(ca = bch2_dev_rcu(c, ptr->dev)) ||
1043 		 dev_ptr_stale_rcu(ca, ptr) > 0));
1044 	rcu_read_unlock();
1045 
1046 	return bkey_deleted(k.k);
1047 }
1048 
1049 /*
1050  * bch2_extent_normalize_by_opts - clean up an extent, dropping stale pointers etc.
1051  *
1052  * Like bch2_extent_normalize(), but also only keeps a single cached pointer on
1053  * the promote target.
1054  */
1055 bool bch2_extent_normalize_by_opts(struct bch_fs *c,
1056 				   struct bch_io_opts *opts,
1057 				   struct bkey_s k)
1058 {
1059 	struct bkey_ptrs ptrs;
1060 	bool have_cached_ptr;
1061 
1062 	rcu_read_lock();
1063 restart_drop_ptrs:
1064 	ptrs = bch2_bkey_ptrs(k);
1065 	have_cached_ptr = false;
1066 
1067 	bkey_for_each_ptr(ptrs, ptr)
1068 		if (ptr->cached) {
1069 			if (have_cached_ptr || !want_cached_ptr(c, opts, ptr)) {
1070 				bch2_bkey_drop_ptr(k, ptr);
1071 				goto restart_drop_ptrs;
1072 			}
1073 			have_cached_ptr = true;
1074 		}
1075 	rcu_read_unlock();
1076 
1077 	return bkey_deleted(k.k);
1078 }
1079 
1080 void bch2_extent_ptr_to_text(struct printbuf *out, struct bch_fs *c, const struct bch_extent_ptr *ptr)
1081 {
1082 	out->atomic++;
1083 	rcu_read_lock();
1084 	struct bch_dev *ca = bch2_dev_rcu_noerror(c, ptr->dev);
1085 	if (!ca) {
1086 		prt_printf(out, "ptr: %u:%llu gen %u%s", ptr->dev,
1087 			   (u64) ptr->offset, ptr->gen,
1088 			   ptr->cached ? " cached" : "");
1089 	} else {
1090 		u32 offset;
1091 		u64 b = sector_to_bucket_and_offset(ca, ptr->offset, &offset);
1092 
1093 		prt_printf(out, "ptr: %u:%llu:%u gen %u",
1094 			   ptr->dev, b, offset, ptr->gen);
1095 		if (ca->mi.durability != 1)
1096 			prt_printf(out, " d=%u", ca->mi.durability);
1097 		if (ptr->cached)
1098 			prt_str(out, " cached");
1099 		if (ptr->unwritten)
1100 			prt_str(out, " unwritten");
1101 		int stale = dev_ptr_stale_rcu(ca, ptr);
1102 		if (stale > 0)
1103 			prt_printf(out, " stale");
1104 		else if (stale)
1105 			prt_printf(out, " invalid");
1106 	}
1107 	rcu_read_unlock();
1108 	--out->atomic;
1109 }
1110 
1111 void bch2_extent_crc_unpacked_to_text(struct printbuf *out, struct bch_extent_crc_unpacked *crc)
1112 {
1113 	prt_printf(out, "crc: c_size %u size %u offset %u nonce %u csum ",
1114 		   crc->compressed_size,
1115 		   crc->uncompressed_size,
1116 		   crc->offset, crc->nonce);
1117 	bch2_prt_csum_type(out, crc->csum_type);
1118 	prt_printf(out, " %0llx:%0llx ", crc->csum.hi, crc->csum.lo);
1119 	prt_str(out, " compress ");
1120 	bch2_prt_compression_type(out, crc->compression_type);
1121 }
1122 
1123 void bch2_bkey_ptrs_to_text(struct printbuf *out, struct bch_fs *c,
1124 			    struct bkey_s_c k)
1125 {
1126 	struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
1127 	const union bch_extent_entry *entry;
1128 	bool first = true;
1129 
1130 	if (c)
1131 		prt_printf(out, "durability: %u ", bch2_bkey_durability_safe(c, k));
1132 
1133 	bkey_extent_entry_for_each(ptrs, entry) {
1134 		if (!first)
1135 			prt_printf(out, " ");
1136 
1137 		switch (__extent_entry_type(entry)) {
1138 		case BCH_EXTENT_ENTRY_ptr:
1139 			bch2_extent_ptr_to_text(out, c, entry_to_ptr(entry));
1140 			break;
1141 
1142 		case BCH_EXTENT_ENTRY_crc32:
1143 		case BCH_EXTENT_ENTRY_crc64:
1144 		case BCH_EXTENT_ENTRY_crc128: {
1145 			struct bch_extent_crc_unpacked crc =
1146 				bch2_extent_crc_unpack(k.k, entry_to_crc(entry));
1147 
1148 			bch2_extent_crc_unpacked_to_text(out, &crc);
1149 			break;
1150 		}
1151 		case BCH_EXTENT_ENTRY_stripe_ptr: {
1152 			const struct bch_extent_stripe_ptr *ec = &entry->stripe_ptr;
1153 
1154 			prt_printf(out, "ec: idx %llu block %u",
1155 			       (u64) ec->idx, ec->block);
1156 			break;
1157 		}
1158 		case BCH_EXTENT_ENTRY_rebalance: {
1159 			const struct bch_extent_rebalance *r = &entry->rebalance;
1160 
1161 			prt_str(out, "rebalance: target ");
1162 			if (c)
1163 				bch2_target_to_text(out, c, r->target);
1164 			else
1165 				prt_printf(out, "%u", r->target);
1166 			prt_str(out, " compression ");
1167 			bch2_compression_opt_to_text(out, r->compression);
1168 			break;
1169 		}
1170 		default:
1171 			prt_printf(out, "(invalid extent entry %.16llx)", *((u64 *) entry));
1172 			return;
1173 		}
1174 
1175 		first = false;
1176 	}
1177 }
1178 
1179 static int extent_ptr_validate(struct bch_fs *c,
1180 			       struct bkey_s_c k,
1181 			       enum bch_validate_flags flags,
1182 			       const struct bch_extent_ptr *ptr,
1183 			       unsigned size_ondisk,
1184 			       bool metadata)
1185 {
1186 	int ret = 0;
1187 
1188 	/* bad pointers are repaired by check_fix_ptrs(): */
1189 	rcu_read_lock();
1190 	struct bch_dev *ca = bch2_dev_rcu_noerror(c, ptr->dev);
1191 	if (!ca) {
1192 		rcu_read_unlock();
1193 		return 0;
1194 	}
1195 	u32 bucket_offset;
1196 	u64 bucket = sector_to_bucket_and_offset(ca, ptr->offset, &bucket_offset);
1197 	unsigned first_bucket	= ca->mi.first_bucket;
1198 	u64 nbuckets		= ca->mi.nbuckets;
1199 	unsigned bucket_size	= ca->mi.bucket_size;
1200 	rcu_read_unlock();
1201 
1202 	struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
1203 	bkey_for_each_ptr(ptrs, ptr2)
1204 		bkey_fsck_err_on(ptr != ptr2 && ptr->dev == ptr2->dev,
1205 				 c, ptr_to_duplicate_device,
1206 				 "multiple pointers to same device (%u)", ptr->dev);
1207 
1208 
1209 	bkey_fsck_err_on(bucket >= nbuckets,
1210 			 c, ptr_after_last_bucket,
1211 			 "pointer past last bucket (%llu > %llu)", bucket, nbuckets);
1212 	bkey_fsck_err_on(bucket < first_bucket,
1213 			 c, ptr_before_first_bucket,
1214 			 "pointer before first bucket (%llu < %u)", bucket, first_bucket);
1215 	bkey_fsck_err_on(bucket_offset + size_ondisk > bucket_size,
1216 			 c, ptr_spans_multiple_buckets,
1217 			 "pointer spans multiple buckets (%u + %u > %u)",
1218 		       bucket_offset, size_ondisk, bucket_size);
1219 fsck_err:
1220 	return ret;
1221 }
1222 
1223 int bch2_bkey_ptrs_validate(struct bch_fs *c, struct bkey_s_c k,
1224 			    enum bch_validate_flags flags)
1225 {
1226 	struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
1227 	const union bch_extent_entry *entry;
1228 	struct bch_extent_crc_unpacked crc;
1229 	unsigned size_ondisk = k.k->size;
1230 	unsigned nonce = UINT_MAX;
1231 	unsigned nr_ptrs = 0;
1232 	bool have_written = false, have_unwritten = false, have_ec = false, crc_since_last_ptr = false;
1233 	int ret = 0;
1234 
1235 	if (bkey_is_btree_ptr(k.k))
1236 		size_ondisk = btree_sectors(c);
1237 
1238 	bkey_extent_entry_for_each(ptrs, entry) {
1239 		bkey_fsck_err_on(__extent_entry_type(entry) >= BCH_EXTENT_ENTRY_MAX,
1240 				 c, extent_ptrs_invalid_entry,
1241 				 "invalid extent entry type (got %u, max %u)",
1242 				 __extent_entry_type(entry), BCH_EXTENT_ENTRY_MAX);
1243 
1244 		bkey_fsck_err_on(bkey_is_btree_ptr(k.k) &&
1245 				 !extent_entry_is_ptr(entry),
1246 				 c, btree_ptr_has_non_ptr,
1247 				 "has non ptr field");
1248 
1249 		switch (extent_entry_type(entry)) {
1250 		case BCH_EXTENT_ENTRY_ptr:
1251 			ret = extent_ptr_validate(c, k, flags, &entry->ptr, size_ondisk, false);
1252 			if (ret)
1253 				return ret;
1254 
1255 			bkey_fsck_err_on(entry->ptr.cached && have_ec,
1256 					 c, ptr_cached_and_erasure_coded,
1257 					 "cached, erasure coded ptr");
1258 
1259 			if (!entry->ptr.unwritten)
1260 				have_written = true;
1261 			else
1262 				have_unwritten = true;
1263 
1264 			have_ec = false;
1265 			crc_since_last_ptr = false;
1266 			nr_ptrs++;
1267 			break;
1268 		case BCH_EXTENT_ENTRY_crc32:
1269 		case BCH_EXTENT_ENTRY_crc64:
1270 		case BCH_EXTENT_ENTRY_crc128:
1271 			crc = bch2_extent_crc_unpack(k.k, entry_to_crc(entry));
1272 
1273 			bkey_fsck_err_on(crc.offset + crc.live_size > crc.uncompressed_size,
1274 					 c, ptr_crc_uncompressed_size_too_small,
1275 					 "checksum offset + key size > uncompressed size");
1276 			bkey_fsck_err_on(!bch2_checksum_type_valid(c, crc.csum_type),
1277 					 c, ptr_crc_csum_type_unknown,
1278 					 "invalid checksum type");
1279 			bkey_fsck_err_on(crc.compression_type >= BCH_COMPRESSION_TYPE_NR,
1280 					 c, ptr_crc_compression_type_unknown,
1281 					 "invalid compression type");
1282 
1283 			if (bch2_csum_type_is_encryption(crc.csum_type)) {
1284 				if (nonce == UINT_MAX)
1285 					nonce = crc.offset + crc.nonce;
1286 				else if (nonce != crc.offset + crc.nonce)
1287 					bkey_fsck_err(c, ptr_crc_nonce_mismatch,
1288 						      "incorrect nonce");
1289 			}
1290 
1291 			bkey_fsck_err_on(crc_since_last_ptr,
1292 					 c, ptr_crc_redundant,
1293 					 "redundant crc entry");
1294 			crc_since_last_ptr = true;
1295 
1296 			bkey_fsck_err_on(crc_is_encoded(crc) &&
1297 					 (crc.uncompressed_size > c->opts.encoded_extent_max >> 9) &&
1298 					 (flags & (BCH_VALIDATE_write|BCH_VALIDATE_commit)),
1299 					 c, ptr_crc_uncompressed_size_too_big,
1300 					 "too large encoded extent");
1301 
1302 			size_ondisk = crc.compressed_size;
1303 			break;
1304 		case BCH_EXTENT_ENTRY_stripe_ptr:
1305 			bkey_fsck_err_on(have_ec,
1306 					 c, ptr_stripe_redundant,
1307 					 "redundant stripe entry");
1308 			have_ec = true;
1309 			break;
1310 		case BCH_EXTENT_ENTRY_rebalance: {
1311 			/*
1312 			 * this shouldn't be a fsck error, for forward
1313 			 * compatibility; the rebalance code should just refetch
1314 			 * the compression opt if it's unknown
1315 			 */
1316 #if 0
1317 			const struct bch_extent_rebalance *r = &entry->rebalance;
1318 
1319 			if (!bch2_compression_opt_valid(r->compression)) {
1320 				struct bch_compression_opt opt = __bch2_compression_decode(r->compression);
1321 				prt_printf(err, "invalid compression opt %u:%u",
1322 					   opt.type, opt.level);
1323 				return -BCH_ERR_invalid_bkey;
1324 			}
1325 #endif
1326 			break;
1327 		}
1328 		}
1329 	}
1330 
1331 	bkey_fsck_err_on(!nr_ptrs,
1332 			 c, extent_ptrs_no_ptrs,
1333 			 "no ptrs");
1334 	bkey_fsck_err_on(nr_ptrs > BCH_BKEY_PTRS_MAX,
1335 			 c, extent_ptrs_too_many_ptrs,
1336 			 "too many ptrs: %u > %u", nr_ptrs, BCH_BKEY_PTRS_MAX);
1337 	bkey_fsck_err_on(have_written && have_unwritten,
1338 			 c, extent_ptrs_written_and_unwritten,
1339 			 "extent with unwritten and written ptrs");
1340 	bkey_fsck_err_on(k.k->type != KEY_TYPE_extent && have_unwritten,
1341 			 c, extent_ptrs_unwritten,
1342 			 "has unwritten ptrs");
1343 	bkey_fsck_err_on(crc_since_last_ptr,
1344 			 c, extent_ptrs_redundant_crc,
1345 			 "redundant crc entry");
1346 	bkey_fsck_err_on(have_ec,
1347 			 c, extent_ptrs_redundant_stripe,
1348 			 "redundant stripe entry");
1349 fsck_err:
1350 	return ret;
1351 }
1352 
1353 void bch2_ptr_swab(struct bkey_s k)
1354 {
1355 	struct bkey_ptrs ptrs = bch2_bkey_ptrs(k);
1356 	union bch_extent_entry *entry;
1357 	u64 *d;
1358 
1359 	for (d =  (u64 *) ptrs.start;
1360 	     d != (u64 *) ptrs.end;
1361 	     d++)
1362 		*d = swab64(*d);
1363 
1364 	for (entry = ptrs.start;
1365 	     entry < ptrs.end;
1366 	     entry = extent_entry_next(entry)) {
1367 		switch (extent_entry_type(entry)) {
1368 		case BCH_EXTENT_ENTRY_ptr:
1369 			break;
1370 		case BCH_EXTENT_ENTRY_crc32:
1371 			entry->crc32.csum = swab32(entry->crc32.csum);
1372 			break;
1373 		case BCH_EXTENT_ENTRY_crc64:
1374 			entry->crc64.csum_hi = swab16(entry->crc64.csum_hi);
1375 			entry->crc64.csum_lo = swab64(entry->crc64.csum_lo);
1376 			break;
1377 		case BCH_EXTENT_ENTRY_crc128:
1378 			entry->crc128.csum.hi = (__force __le64)
1379 				swab64((__force u64) entry->crc128.csum.hi);
1380 			entry->crc128.csum.lo = (__force __le64)
1381 				swab64((__force u64) entry->crc128.csum.lo);
1382 			break;
1383 		case BCH_EXTENT_ENTRY_stripe_ptr:
1384 			break;
1385 		case BCH_EXTENT_ENTRY_rebalance:
1386 			break;
1387 		}
1388 	}
1389 }
1390 
1391 const struct bch_extent_rebalance *bch2_bkey_rebalance_opts(struct bkey_s_c k)
1392 {
1393 	struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
1394 	const union bch_extent_entry *entry;
1395 
1396 	bkey_extent_entry_for_each(ptrs, entry)
1397 		if (__extent_entry_type(entry) == BCH_EXTENT_ENTRY_rebalance)
1398 			return &entry->rebalance;
1399 
1400 	return NULL;
1401 }
1402 
1403 unsigned bch2_bkey_ptrs_need_rebalance(struct bch_fs *c, struct bkey_s_c k,
1404 				       unsigned target, unsigned compression)
1405 {
1406 	struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
1407 	unsigned rewrite_ptrs = 0;
1408 
1409 	if (compression) {
1410 		unsigned compression_type = bch2_compression_opt_to_type(compression);
1411 		const union bch_extent_entry *entry;
1412 		struct extent_ptr_decoded p;
1413 		unsigned i = 0;
1414 
1415 		bkey_for_each_ptr_decode(k.k, ptrs, p, entry) {
1416 			if (p.crc.compression_type == BCH_COMPRESSION_TYPE_incompressible ||
1417 			    p.ptr.unwritten) {
1418 				rewrite_ptrs = 0;
1419 				goto incompressible;
1420 			}
1421 
1422 			if (!p.ptr.cached && p.crc.compression_type != compression_type)
1423 				rewrite_ptrs |= 1U << i;
1424 			i++;
1425 		}
1426 	}
1427 incompressible:
1428 	if (target && bch2_target_accepts_data(c, BCH_DATA_user, target)) {
1429 		unsigned i = 0;
1430 
1431 		bkey_for_each_ptr(ptrs, ptr) {
1432 			if (!ptr->cached && !bch2_dev_in_target(c, ptr->dev, target))
1433 				rewrite_ptrs |= 1U << i;
1434 			i++;
1435 		}
1436 	}
1437 
1438 	return rewrite_ptrs;
1439 }
1440 
1441 bool bch2_bkey_needs_rebalance(struct bch_fs *c, struct bkey_s_c k)
1442 {
1443 	const struct bch_extent_rebalance *r = bch2_bkey_rebalance_opts(k);
1444 
1445 	/*
1446 	 * If it's an indirect extent, we don't delete the rebalance entry when
1447 	 * done so that we know what options were applied - check if it still
1448 	 * needs work done:
1449 	 */
1450 	if (r &&
1451 	    k.k->type == KEY_TYPE_reflink_v &&
1452 	    !bch2_bkey_ptrs_need_rebalance(c, k, r->target, r->compression))
1453 		r = NULL;
1454 
1455 	return r != NULL;
1456 }
1457 
1458 static u64 __bch2_bkey_sectors_need_rebalance(struct bch_fs *c, struct bkey_s_c k,
1459 				       unsigned target, unsigned compression)
1460 {
1461 	struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
1462 	const union bch_extent_entry *entry;
1463 	struct extent_ptr_decoded p;
1464 	u64 sectors = 0;
1465 
1466 	if (compression) {
1467 		unsigned compression_type = bch2_compression_opt_to_type(compression);
1468 
1469 		bkey_for_each_ptr_decode(k.k, ptrs, p, entry) {
1470 			if (p.crc.compression_type == BCH_COMPRESSION_TYPE_incompressible ||
1471 			    p.ptr.unwritten) {
1472 				sectors = 0;
1473 				goto incompressible;
1474 			}
1475 
1476 			if (!p.ptr.cached && p.crc.compression_type != compression_type)
1477 				sectors += p.crc.compressed_size;
1478 		}
1479 	}
1480 incompressible:
1481 	if (target && bch2_target_accepts_data(c, BCH_DATA_user, target)) {
1482 		bkey_for_each_ptr_decode(k.k, ptrs, p, entry)
1483 			if (!p.ptr.cached && !bch2_dev_in_target(c, p.ptr.dev, target))
1484 				sectors += p.crc.compressed_size;
1485 	}
1486 
1487 	return sectors;
1488 }
1489 
1490 u64 bch2_bkey_sectors_need_rebalance(struct bch_fs *c, struct bkey_s_c k)
1491 {
1492 	const struct bch_extent_rebalance *r = bch2_bkey_rebalance_opts(k);
1493 
1494 	return r ? __bch2_bkey_sectors_need_rebalance(c, k, r->target, r->compression) : 0;
1495 }
1496 
1497 int bch2_bkey_set_needs_rebalance(struct bch_fs *c, struct bkey_i *_k,
1498 				  struct bch_io_opts *opts)
1499 {
1500 	struct bkey_s k = bkey_i_to_s(_k);
1501 	struct bch_extent_rebalance *r;
1502 	unsigned target = opts->background_target;
1503 	unsigned compression = background_compression(*opts);
1504 	bool needs_rebalance;
1505 
1506 	if (!bkey_extent_is_direct_data(k.k))
1507 		return 0;
1508 
1509 	/* get existing rebalance entry: */
1510 	r = (struct bch_extent_rebalance *) bch2_bkey_rebalance_opts(k.s_c);
1511 	if (r) {
1512 		if (k.k->type == KEY_TYPE_reflink_v) {
1513 			/*
1514 			 * indirect extents: existing options take precedence,
1515 			 * so that we don't move extents back and forth if
1516 			 * they're referenced by different inodes with different
1517 			 * options:
1518 			 */
1519 			if (r->target)
1520 				target = r->target;
1521 			if (r->compression)
1522 				compression = r->compression;
1523 		}
1524 
1525 		r->target	= target;
1526 		r->compression	= compression;
1527 	}
1528 
1529 	needs_rebalance = bch2_bkey_ptrs_need_rebalance(c, k.s_c, target, compression);
1530 
1531 	if (needs_rebalance && !r) {
1532 		union bch_extent_entry *new = bkey_val_end(k);
1533 
1534 		new->rebalance.type		= 1U << BCH_EXTENT_ENTRY_rebalance;
1535 		new->rebalance.compression	= compression;
1536 		new->rebalance.target		= target;
1537 		new->rebalance.unused		= 0;
1538 		k.k->u64s += extent_entry_u64s(new);
1539 	} else if (!needs_rebalance && r && k.k->type != KEY_TYPE_reflink_v) {
1540 		/*
1541 		 * For indirect extents, don't delete the rebalance entry when
1542 		 * we're finished so that we know we specifically moved it or
1543 		 * compressed it to its current location/compression type
1544 		 */
1545 		extent_entry_drop(k, (union bch_extent_entry *) r);
1546 	}
1547 
1548 	return 0;
1549 }
1550 
1551 /* Generic extent code: */
1552 
1553 int bch2_cut_front_s(struct bpos where, struct bkey_s k)
1554 {
1555 	unsigned new_val_u64s = bkey_val_u64s(k.k);
1556 	int val_u64s_delta;
1557 	u64 sub;
1558 
1559 	if (bkey_le(where, bkey_start_pos(k.k)))
1560 		return 0;
1561 
1562 	EBUG_ON(bkey_gt(where, k.k->p));
1563 
1564 	sub = where.offset - bkey_start_offset(k.k);
1565 
1566 	k.k->size -= sub;
1567 
1568 	if (!k.k->size) {
1569 		k.k->type = KEY_TYPE_deleted;
1570 		new_val_u64s = 0;
1571 	}
1572 
1573 	switch (k.k->type) {
1574 	case KEY_TYPE_extent:
1575 	case KEY_TYPE_reflink_v: {
1576 		struct bkey_ptrs ptrs = bch2_bkey_ptrs(k);
1577 		union bch_extent_entry *entry;
1578 		bool seen_crc = false;
1579 
1580 		bkey_extent_entry_for_each(ptrs, entry) {
1581 			switch (extent_entry_type(entry)) {
1582 			case BCH_EXTENT_ENTRY_ptr:
1583 				if (!seen_crc)
1584 					entry->ptr.offset += sub;
1585 				break;
1586 			case BCH_EXTENT_ENTRY_crc32:
1587 				entry->crc32.offset += sub;
1588 				break;
1589 			case BCH_EXTENT_ENTRY_crc64:
1590 				entry->crc64.offset += sub;
1591 				break;
1592 			case BCH_EXTENT_ENTRY_crc128:
1593 				entry->crc128.offset += sub;
1594 				break;
1595 			case BCH_EXTENT_ENTRY_stripe_ptr:
1596 				break;
1597 			case BCH_EXTENT_ENTRY_rebalance:
1598 				break;
1599 			}
1600 
1601 			if (extent_entry_is_crc(entry))
1602 				seen_crc = true;
1603 		}
1604 
1605 		break;
1606 	}
1607 	case KEY_TYPE_reflink_p: {
1608 		struct bkey_s_reflink_p p = bkey_s_to_reflink_p(k);
1609 
1610 		le64_add_cpu(&p.v->idx, sub);
1611 		break;
1612 	}
1613 	case KEY_TYPE_inline_data:
1614 	case KEY_TYPE_indirect_inline_data: {
1615 		void *p = bkey_inline_data_p(k);
1616 		unsigned bytes = bkey_inline_data_bytes(k.k);
1617 
1618 		sub = min_t(u64, sub << 9, bytes);
1619 
1620 		memmove(p, p + sub, bytes - sub);
1621 
1622 		new_val_u64s -= sub >> 3;
1623 		break;
1624 	}
1625 	}
1626 
1627 	val_u64s_delta = bkey_val_u64s(k.k) - new_val_u64s;
1628 	BUG_ON(val_u64s_delta < 0);
1629 
1630 	set_bkey_val_u64s(k.k, new_val_u64s);
1631 	memset(bkey_val_end(k), 0, val_u64s_delta * sizeof(u64));
1632 	return -val_u64s_delta;
1633 }
1634 
1635 int bch2_cut_back_s(struct bpos where, struct bkey_s k)
1636 {
1637 	unsigned new_val_u64s = bkey_val_u64s(k.k);
1638 	int val_u64s_delta;
1639 	u64 len = 0;
1640 
1641 	if (bkey_ge(where, k.k->p))
1642 		return 0;
1643 
1644 	EBUG_ON(bkey_lt(where, bkey_start_pos(k.k)));
1645 
1646 	len = where.offset - bkey_start_offset(k.k);
1647 
1648 	k.k->p.offset = where.offset;
1649 	k.k->size = len;
1650 
1651 	if (!len) {
1652 		k.k->type = KEY_TYPE_deleted;
1653 		new_val_u64s = 0;
1654 	}
1655 
1656 	switch (k.k->type) {
1657 	case KEY_TYPE_inline_data:
1658 	case KEY_TYPE_indirect_inline_data:
1659 		new_val_u64s = (bkey_inline_data_offset(k.k) +
1660 				min(bkey_inline_data_bytes(k.k), k.k->size << 9)) >> 3;
1661 		break;
1662 	}
1663 
1664 	val_u64s_delta = bkey_val_u64s(k.k) - new_val_u64s;
1665 	BUG_ON(val_u64s_delta < 0);
1666 
1667 	set_bkey_val_u64s(k.k, new_val_u64s);
1668 	memset(bkey_val_end(k), 0, val_u64s_delta * sizeof(u64));
1669 	return -val_u64s_delta;
1670 }
1671