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   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
  30static 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
  36static void bch2_extent_crc_pack(union bch_extent_crc *,
  37				 struct bch_extent_crc_unpacked,
  38				 enum bch_extent_entry_type);
  39
  40static struct bch_dev_io_failures *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
  52void bch2_mark_io_failure(struct bch_io_failures *failed,
  53			  struct extent_ptr_decoded *p)
  54{
  55	struct bch_dev_io_failures *f = 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/*
  75 * returns true if p1 is better than p2:
  76 */
  77static inline bool ptr_better(struct bch_fs *c,
  78			      const struct extent_ptr_decoded p1,
  79			      const struct extent_ptr_decoded p2)
  80{
  81	if (likely(!p1.idx && !p2.idx)) {
  82		struct bch_dev *dev1 = bch_dev_bkey_exists(c, p1.ptr.dev);
  83		struct bch_dev *dev2 = bch_dev_bkey_exists(c, p2.ptr.dev);
  84
  85		u64 l1 = atomic64_read(&dev1->cur_latency[READ]);
  86		u64 l2 = atomic64_read(&dev2->cur_latency[READ]);
  87
  88		/* Pick at random, biased in favor of the faster device: */
  89
  90		return bch2_rand_range(l1 + l2) > l1;
  91	}
  92
  93	if (bch2_force_reconstruct_read)
  94		return p1.idx > p2.idx;
  95
  96	return p1.idx < p2.idx;
  97}
  98
  99/*
 100 * This picks a non-stale pointer, preferably from a device other than @avoid.
 101 * Avoid can be NULL, meaning pick any. If there are no non-stale pointers to
 102 * other devices, it will still pick a pointer from avoid.
 103 */
 104int bch2_bkey_pick_read_device(struct bch_fs *c, struct bkey_s_c k,
 105			       struct bch_io_failures *failed,
 106			       struct extent_ptr_decoded *pick)
 107{
 108	struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
 109	const union bch_extent_entry *entry;
 110	struct extent_ptr_decoded p;
 111	struct bch_dev_io_failures *f;
 112	struct bch_dev *ca;
 113	int ret = 0;
 114
 115	if (k.k->type == KEY_TYPE_error)
 116		return -EIO;
 117
 118	bkey_for_each_ptr_decode(k.k, ptrs, p, entry) {
 119		/*
 120		 * Unwritten extent: no need to actually read, treat it as a
 121		 * hole and return 0s:
 122		 */
 123		if (p.ptr.unwritten)
 124			return 0;
 125
 126		ca = bch_dev_bkey_exists(c, p.ptr.dev);
 127
 128		/*
 129		 * If there are any dirty pointers it's an error if we can't
 130		 * read:
 131		 */
 132		if (!ret && !p.ptr.cached)
 133			ret = -EIO;
 134
 135		if (p.ptr.cached && ptr_stale(ca, &p.ptr))
 136			continue;
 137
 138		f = failed ? dev_io_failures(failed, p.ptr.dev) : NULL;
 139		if (f)
 140			p.idx = f->nr_failed < f->nr_retries
 141				? f->idx
 142				: f->idx + 1;
 143
 144		if (!p.idx &&
 145		    !bch2_dev_is_readable(ca))
 146			p.idx++;
 147
 148		if (bch2_force_reconstruct_read &&
 149		    !p.idx && p.has_ec)
 150			p.idx++;
 151
 152		if (p.idx >= (unsigned) p.has_ec + 1)
 153			continue;
 154
 155		if (ret > 0 && !ptr_better(c, p, *pick))
 156			continue;
 157
 158		*pick = p;
 159		ret = 1;
 160	}
 161
 162	return ret;
 163}
 164
 165/* KEY_TYPE_btree_ptr: */
 166
 167int bch2_btree_ptr_invalid(struct bch_fs *c, struct bkey_s_c k,
 168			   enum bkey_invalid_flags flags,
 169			   struct printbuf *err)
 170{
 171	int ret = 0;
 172
 173	bkey_fsck_err_on(bkey_val_u64s(k.k) > BCH_REPLICAS_MAX, c, err,
 174			 btree_ptr_val_too_big,
 175			 "value too big (%zu > %u)", bkey_val_u64s(k.k), BCH_REPLICAS_MAX);
 176
 177	ret = bch2_bkey_ptrs_invalid(c, k, flags, err);
 178fsck_err:
 179	return ret;
 180}
 181
 182void bch2_btree_ptr_to_text(struct printbuf *out, struct bch_fs *c,
 183			    struct bkey_s_c k)
 184{
 185	bch2_bkey_ptrs_to_text(out, c, k);
 186}
 187
 188int bch2_btree_ptr_v2_invalid(struct bch_fs *c, struct bkey_s_c k,
 189			      enum bkey_invalid_flags flags,
 190			      struct printbuf *err)
 191{
 192	int ret = 0;
 193
 194	bkey_fsck_err_on(bkey_val_u64s(k.k) > BKEY_BTREE_PTR_VAL_U64s_MAX, c, err,
 195			 btree_ptr_v2_val_too_big,
 196			 "value too big (%zu > %zu)",
 197			 bkey_val_u64s(k.k), BKEY_BTREE_PTR_VAL_U64s_MAX);
 198
 199	ret = bch2_bkey_ptrs_invalid(c, k, flags, err);
 200fsck_err:
 201	return ret;
 202}
 203
 204void bch2_btree_ptr_v2_to_text(struct printbuf *out, struct bch_fs *c,
 205			       struct bkey_s_c k)
 206{
 207	struct bkey_s_c_btree_ptr_v2 bp = bkey_s_c_to_btree_ptr_v2(k);
 208
 209	prt_printf(out, "seq %llx written %u min_key %s",
 210	       le64_to_cpu(bp.v->seq),
 211	       le16_to_cpu(bp.v->sectors_written),
 212	       BTREE_PTR_RANGE_UPDATED(bp.v) ? "R " : "");
 213
 214	bch2_bpos_to_text(out, bp.v->min_key);
 215	prt_printf(out, " ");
 216	bch2_bkey_ptrs_to_text(out, c, k);
 217}
 218
 219void bch2_btree_ptr_v2_compat(enum btree_id btree_id, unsigned version,
 220			      unsigned big_endian, int write,
 221			      struct bkey_s k)
 222{
 223	struct bkey_s_btree_ptr_v2 bp = bkey_s_to_btree_ptr_v2(k);
 224
 225	compat_bpos(0, btree_id, version, big_endian, write, &bp.v->min_key);
 226
 227	if (version < bcachefs_metadata_version_inode_btree_change &&
 228	    btree_id_is_extents(btree_id) &&
 229	    !bkey_eq(bp.v->min_key, POS_MIN))
 230		bp.v->min_key = write
 231			? bpos_nosnap_predecessor(bp.v->min_key)
 232			: bpos_nosnap_successor(bp.v->min_key);
 233}
 234
 235/* KEY_TYPE_extent: */
 236
 237bool bch2_extent_merge(struct bch_fs *c, struct bkey_s l, struct bkey_s_c r)
 238{
 239	struct bkey_ptrs   l_ptrs = bch2_bkey_ptrs(l);
 240	struct bkey_ptrs_c r_ptrs = bch2_bkey_ptrs_c(r);
 241	union bch_extent_entry *en_l;
 242	const union bch_extent_entry *en_r;
 243	struct extent_ptr_decoded lp, rp;
 244	bool use_right_ptr;
 245	struct bch_dev *ca;
 246
 247	en_l = l_ptrs.start;
 248	en_r = r_ptrs.start;
 249	while (en_l < l_ptrs.end && en_r < r_ptrs.end) {
 250		if (extent_entry_type(en_l) != extent_entry_type(en_r))
 251			return false;
 252
 253		en_l = extent_entry_next(en_l);
 254		en_r = extent_entry_next(en_r);
 255	}
 256
 257	if (en_l < l_ptrs.end || en_r < r_ptrs.end)
 258		return false;
 259
 260	en_l = l_ptrs.start;
 261	en_r = r_ptrs.start;
 262	lp.crc = bch2_extent_crc_unpack(l.k, NULL);
 263	rp.crc = bch2_extent_crc_unpack(r.k, NULL);
 264
 265	while (__bkey_ptr_next_decode(l.k, l_ptrs.end, lp, en_l) &&
 266	       __bkey_ptr_next_decode(r.k, r_ptrs.end, rp, en_r)) {
 267		if (lp.ptr.offset + lp.crc.offset + lp.crc.live_size !=
 268		    rp.ptr.offset + rp.crc.offset ||
 269		    lp.ptr.dev			!= rp.ptr.dev ||
 270		    lp.ptr.gen			!= rp.ptr.gen ||
 271		    lp.ptr.unwritten		!= rp.ptr.unwritten ||
 272		    lp.has_ec			!= rp.has_ec)
 273			return false;
 274
 275		/* Extents may not straddle buckets: */
 276		ca = bch_dev_bkey_exists(c, lp.ptr.dev);
 277		if (PTR_BUCKET_NR(ca, &lp.ptr) != PTR_BUCKET_NR(ca, &rp.ptr))
 278			return false;
 279
 280		if (lp.has_ec			!= rp.has_ec ||
 281		    (lp.has_ec &&
 282		     (lp.ec.block		!= rp.ec.block ||
 283		      lp.ec.redundancy		!= rp.ec.redundancy ||
 284		      lp.ec.idx			!= rp.ec.idx)))
 285			return false;
 286
 287		if (lp.crc.compression_type	!= rp.crc.compression_type ||
 288		    lp.crc.nonce		!= rp.crc.nonce)
 289			return false;
 290
 291		if (lp.crc.offset + lp.crc.live_size + rp.crc.live_size <=
 292		    lp.crc.uncompressed_size) {
 293			/* can use left extent's crc entry */
 294		} else if (lp.crc.live_size <= rp.crc.offset) {
 295			/* can use right extent's crc entry */
 296		} else {
 297			/* check if checksums can be merged: */
 298			if (lp.crc.csum_type		!= rp.crc.csum_type ||
 299			    lp.crc.nonce		!= rp.crc.nonce ||
 300			    crc_is_compressed(lp.crc) ||
 301			    !bch2_checksum_mergeable(lp.crc.csum_type))
 302				return false;
 303
 304			if (lp.crc.offset + lp.crc.live_size != lp.crc.compressed_size ||
 305			    rp.crc.offset)
 306				return false;
 307
 308			if (lp.crc.csum_type &&
 309			    lp.crc.uncompressed_size +
 310			    rp.crc.uncompressed_size > (c->opts.encoded_extent_max >> 9))
 311				return false;
 312		}
 313
 314		en_l = extent_entry_next(en_l);
 315		en_r = extent_entry_next(en_r);
 316	}
 317
 318	en_l = l_ptrs.start;
 319	en_r = r_ptrs.start;
 320	while (en_l < l_ptrs.end && en_r < r_ptrs.end) {
 321		if (extent_entry_is_crc(en_l)) {
 322			struct bch_extent_crc_unpacked crc_l = bch2_extent_crc_unpack(l.k, entry_to_crc(en_l));
 323			struct bch_extent_crc_unpacked crc_r = bch2_extent_crc_unpack(r.k, entry_to_crc(en_r));
 324
 325			if (crc_l.uncompressed_size + crc_r.uncompressed_size >
 326			    bch2_crc_field_size_max[extent_entry_type(en_l)])
 327				return false;
 328		}
 329
 330		en_l = extent_entry_next(en_l);
 331		en_r = extent_entry_next(en_r);
 332	}
 333
 334	use_right_ptr = false;
 335	en_l = l_ptrs.start;
 336	en_r = r_ptrs.start;
 337	while (en_l < l_ptrs.end) {
 338		if (extent_entry_type(en_l) == BCH_EXTENT_ENTRY_ptr &&
 339		    use_right_ptr)
 340			en_l->ptr = en_r->ptr;
 341
 342		if (extent_entry_is_crc(en_l)) {
 343			struct bch_extent_crc_unpacked crc_l =
 344				bch2_extent_crc_unpack(l.k, entry_to_crc(en_l));
 345			struct bch_extent_crc_unpacked crc_r =
 346				bch2_extent_crc_unpack(r.k, entry_to_crc(en_r));
 347
 348			use_right_ptr = false;
 349
 350			if (crc_l.offset + crc_l.live_size + crc_r.live_size <=
 351			    crc_l.uncompressed_size) {
 352				/* can use left extent's crc entry */
 353			} else if (crc_l.live_size <= crc_r.offset) {
 354				/* can use right extent's crc entry */
 355				crc_r.offset -= crc_l.live_size;
 356				bch2_extent_crc_pack(entry_to_crc(en_l), crc_r,
 357						     extent_entry_type(en_l));
 358				use_right_ptr = true;
 359			} else {
 360				crc_l.csum = bch2_checksum_merge(crc_l.csum_type,
 361								 crc_l.csum,
 362								 crc_r.csum,
 363								 crc_r.uncompressed_size << 9);
 364
 365				crc_l.uncompressed_size	+= crc_r.uncompressed_size;
 366				crc_l.compressed_size	+= crc_r.compressed_size;
 367				bch2_extent_crc_pack(entry_to_crc(en_l), crc_l,
 368						     extent_entry_type(en_l));
 369			}
 370		}
 371
 372		en_l = extent_entry_next(en_l);
 373		en_r = extent_entry_next(en_r);
 374	}
 375
 376	bch2_key_resize(l.k, l.k->size + r.k->size);
 377	return true;
 378}
 379
 380/* KEY_TYPE_reservation: */
 381
 382int bch2_reservation_invalid(struct bch_fs *c, struct bkey_s_c k,
 383			     enum bkey_invalid_flags flags,
 384			     struct printbuf *err)
 385{
 386	struct bkey_s_c_reservation r = bkey_s_c_to_reservation(k);
 387	int ret = 0;
 388
 389	bkey_fsck_err_on(!r.v->nr_replicas || r.v->nr_replicas > BCH_REPLICAS_MAX, c, err,
 390			 reservation_key_nr_replicas_invalid,
 391			 "invalid nr_replicas (%u)", r.v->nr_replicas);
 392fsck_err:
 393	return ret;
 394}
 395
 396void bch2_reservation_to_text(struct printbuf *out, struct bch_fs *c,
 397			      struct bkey_s_c k)
 398{
 399	struct bkey_s_c_reservation r = bkey_s_c_to_reservation(k);
 400
 401	prt_printf(out, "generation %u replicas %u",
 402	       le32_to_cpu(r.v->generation),
 403	       r.v->nr_replicas);
 404}
 405
 406bool bch2_reservation_merge(struct bch_fs *c, struct bkey_s _l, struct bkey_s_c _r)
 407{
 408	struct bkey_s_reservation l = bkey_s_to_reservation(_l);
 409	struct bkey_s_c_reservation r = bkey_s_c_to_reservation(_r);
 410
 411	if (l.v->generation != r.v->generation ||
 412	    l.v->nr_replicas != r.v->nr_replicas)
 413		return false;
 414
 415	bch2_key_resize(l.k, l.k->size + r.k->size);
 416	return true;
 417}
 418
 419/* Extent checksum entries: */
 420
 421/* returns true if not equal */
 422static inline bool bch2_crc_unpacked_cmp(struct bch_extent_crc_unpacked l,
 423					 struct bch_extent_crc_unpacked r)
 424{
 425	return (l.csum_type		!= r.csum_type ||
 426		l.compression_type	!= r.compression_type ||
 427		l.compressed_size	!= r.compressed_size ||
 428		l.uncompressed_size	!= r.uncompressed_size ||
 429		l.offset		!= r.offset ||
 430		l.live_size		!= r.live_size ||
 431		l.nonce			!= r.nonce ||
 432		bch2_crc_cmp(l.csum, r.csum));
 433}
 434
 435static inline bool can_narrow_crc(struct bch_extent_crc_unpacked u,
 436				  struct bch_extent_crc_unpacked n)
 437{
 438	return !crc_is_compressed(u) &&
 439		u.csum_type &&
 440		u.uncompressed_size > u.live_size &&
 441		bch2_csum_type_is_encryption(u.csum_type) ==
 442		bch2_csum_type_is_encryption(n.csum_type);
 443}
 444
 445bool bch2_can_narrow_extent_crcs(struct bkey_s_c k,
 446				 struct bch_extent_crc_unpacked n)
 447{
 448	struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
 449	struct bch_extent_crc_unpacked crc;
 450	const union bch_extent_entry *i;
 451
 452	if (!n.csum_type)
 453		return false;
 454
 455	bkey_for_each_crc(k.k, ptrs, crc, i)
 456		if (can_narrow_crc(crc, n))
 457			return true;
 458
 459	return false;
 460}
 461
 462/*
 463 * We're writing another replica for this extent, so while we've got the data in
 464 * memory we'll be computing a new checksum for the currently live data.
 465 *
 466 * If there are other replicas we aren't moving, and they are checksummed but
 467 * not compressed, we can modify them to point to only the data that is
 468 * currently live (so that readers won't have to bounce) while we've got the
 469 * checksum we need:
 470 */
 471bool bch2_bkey_narrow_crcs(struct bkey_i *k, struct bch_extent_crc_unpacked n)
 472{
 473	struct bkey_ptrs ptrs = bch2_bkey_ptrs(bkey_i_to_s(k));
 474	struct bch_extent_crc_unpacked u;
 475	struct extent_ptr_decoded p;
 476	union bch_extent_entry *i;
 477	bool ret = false;
 478
 479	/* Find a checksum entry that covers only live data: */
 480	if (!n.csum_type) {
 481		bkey_for_each_crc(&k->k, ptrs, u, i)
 482			if (!crc_is_compressed(u) &&
 483			    u.csum_type &&
 484			    u.live_size == u.uncompressed_size) {
 485				n = u;
 486				goto found;
 487			}
 488		return false;
 489	}
 490found:
 491	BUG_ON(crc_is_compressed(n));
 492	BUG_ON(n.offset);
 493	BUG_ON(n.live_size != k->k.size);
 494
 495restart_narrow_pointers:
 496	ptrs = bch2_bkey_ptrs(bkey_i_to_s(k));
 497
 498	bkey_for_each_ptr_decode(&k->k, ptrs, p, i)
 499		if (can_narrow_crc(p.crc, n)) {
 500			bch2_bkey_drop_ptr_noerror(bkey_i_to_s(k), &i->ptr);
 501			p.ptr.offset += p.crc.offset;
 502			p.crc = n;
 503			bch2_extent_ptr_decoded_append(k, &p);
 504			ret = true;
 505			goto restart_narrow_pointers;
 506		}
 507
 508	return ret;
 509}
 510
 511static void bch2_extent_crc_pack(union bch_extent_crc *dst,
 512				 struct bch_extent_crc_unpacked src,
 513				 enum bch_extent_entry_type type)
 514{
 515#define set_common_fields(_dst, _src)					\
 516		_dst.type		= 1 << type;			\
 517		_dst.csum_type		= _src.csum_type,		\
 518		_dst.compression_type	= _src.compression_type,	\
 519		_dst._compressed_size	= _src.compressed_size - 1,	\
 520		_dst._uncompressed_size	= _src.uncompressed_size - 1,	\
 521		_dst.offset		= _src.offset
 522
 523	switch (type) {
 524	case BCH_EXTENT_ENTRY_crc32:
 525		set_common_fields(dst->crc32, src);
 526		dst->crc32.csum		= (u32 __force) *((__le32 *) &src.csum.lo);
 527		break;
 528	case BCH_EXTENT_ENTRY_crc64:
 529		set_common_fields(dst->crc64, src);
 530		dst->crc64.nonce	= src.nonce;
 531		dst->crc64.csum_lo	= (u64 __force) src.csum.lo;
 532		dst->crc64.csum_hi	= (u64 __force) *((__le16 *) &src.csum.hi);
 533		break;
 534	case BCH_EXTENT_ENTRY_crc128:
 535		set_common_fields(dst->crc128, src);
 536		dst->crc128.nonce	= src.nonce;
 537		dst->crc128.csum	= src.csum;
 538		break;
 539	default:
 540		BUG();
 541	}
 542#undef set_common_fields
 543}
 544
 545void bch2_extent_crc_append(struct bkey_i *k,
 546			    struct bch_extent_crc_unpacked new)
 547{
 548	struct bkey_ptrs ptrs = bch2_bkey_ptrs(bkey_i_to_s(k));
 549	union bch_extent_crc *crc = (void *) ptrs.end;
 550	enum bch_extent_entry_type type;
 551
 552	if (bch_crc_bytes[new.csum_type]	<= 4 &&
 553	    new.uncompressed_size		<= CRC32_SIZE_MAX &&
 554	    new.nonce				<= CRC32_NONCE_MAX)
 555		type = BCH_EXTENT_ENTRY_crc32;
 556	else if (bch_crc_bytes[new.csum_type]	<= 10 &&
 557		   new.uncompressed_size	<= CRC64_SIZE_MAX &&
 558		   new.nonce			<= CRC64_NONCE_MAX)
 559		type = BCH_EXTENT_ENTRY_crc64;
 560	else if (bch_crc_bytes[new.csum_type]	<= 16 &&
 561		   new.uncompressed_size	<= CRC128_SIZE_MAX &&
 562		   new.nonce			<= CRC128_NONCE_MAX)
 563		type = BCH_EXTENT_ENTRY_crc128;
 564	else
 565		BUG();
 566
 567	bch2_extent_crc_pack(crc, new, type);
 568
 569	k->k.u64s += extent_entry_u64s(ptrs.end);
 570
 571	EBUG_ON(bkey_val_u64s(&k->k) > BKEY_EXTENT_VAL_U64s_MAX);
 572}
 573
 574/* Generic code for keys with pointers: */
 575
 576unsigned bch2_bkey_nr_ptrs(struct bkey_s_c k)
 577{
 578	return bch2_bkey_devs(k).nr;
 579}
 580
 581unsigned bch2_bkey_nr_ptrs_allocated(struct bkey_s_c k)
 582{
 583	return k.k->type == KEY_TYPE_reservation
 584		? bkey_s_c_to_reservation(k).v->nr_replicas
 585		: bch2_bkey_dirty_devs(k).nr;
 586}
 587
 588unsigned bch2_bkey_nr_ptrs_fully_allocated(struct bkey_s_c k)
 589{
 590	unsigned ret = 0;
 591
 592	if (k.k->type == KEY_TYPE_reservation) {
 593		ret = bkey_s_c_to_reservation(k).v->nr_replicas;
 594	} else {
 595		struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
 596		const union bch_extent_entry *entry;
 597		struct extent_ptr_decoded p;
 598
 599		bkey_for_each_ptr_decode(k.k, ptrs, p, entry)
 600			ret += !p.ptr.cached && !crc_is_compressed(p.crc);
 601	}
 602
 603	return ret;
 604}
 605
 606unsigned bch2_bkey_sectors_compressed(struct bkey_s_c k)
 607{
 608	struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
 609	const union bch_extent_entry *entry;
 610	struct extent_ptr_decoded p;
 611	unsigned ret = 0;
 612
 613	bkey_for_each_ptr_decode(k.k, ptrs, p, entry)
 614		if (!p.ptr.cached && crc_is_compressed(p.crc))
 615			ret += p.crc.compressed_size;
 616
 617	return ret;
 618}
 619
 620bool bch2_bkey_is_incompressible(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 bch_extent_crc_unpacked crc;
 625
 626	bkey_for_each_crc(k.k, ptrs, crc, entry)
 627		if (crc.compression_type == BCH_COMPRESSION_TYPE_incompressible)
 628			return true;
 629	return false;
 630}
 631
 632unsigned bch2_bkey_replicas(struct bch_fs *c, struct bkey_s_c k)
 633{
 634	struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
 635	const union bch_extent_entry *entry;
 636	struct extent_ptr_decoded p = { 0 };
 637	unsigned replicas = 0;
 638
 639	bkey_for_each_ptr_decode(k.k, ptrs, p, entry) {
 640		if (p.ptr.cached)
 641			continue;
 642
 643		if (p.has_ec)
 644			replicas += p.ec.redundancy;
 645
 646		replicas++;
 647
 648	}
 649
 650	return replicas;
 651}
 652
 653static inline unsigned __extent_ptr_durability(struct bch_dev *ca, struct extent_ptr_decoded *p)
 654{
 655	if (p->ptr.cached)
 656		return 0;
 657
 658	return p->has_ec
 659		? p->ec.redundancy + 1
 660		: ca->mi.durability;
 661}
 662
 663unsigned bch2_extent_ptr_desired_durability(struct bch_fs *c, struct extent_ptr_decoded *p)
 664{
 665	struct bch_dev *ca = bch_dev_bkey_exists(c, p->ptr.dev);
 666
 667	return __extent_ptr_durability(ca, p);
 668}
 669
 670unsigned bch2_extent_ptr_durability(struct bch_fs *c, struct extent_ptr_decoded *p)
 671{
 672	struct bch_dev *ca = bch_dev_bkey_exists(c, p->ptr.dev);
 673
 674	if (ca->mi.state == BCH_MEMBER_STATE_failed)
 675		return 0;
 676
 677	return __extent_ptr_durability(ca, p);
 678}
 679
 680unsigned bch2_bkey_durability(struct bch_fs *c, struct bkey_s_c k)
 681{
 682	struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
 683	const union bch_extent_entry *entry;
 684	struct extent_ptr_decoded p;
 685	unsigned durability = 0;
 686
 687	bkey_for_each_ptr_decode(k.k, ptrs, p, entry)
 688		durability += bch2_extent_ptr_durability(c, &p);
 689
 690	return durability;
 691}
 692
 693static unsigned bch2_bkey_durability_safe(struct bch_fs *c, struct bkey_s_c k)
 694{
 695	struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
 696	const union bch_extent_entry *entry;
 697	struct extent_ptr_decoded p;
 698	unsigned durability = 0;
 699
 700	bkey_for_each_ptr_decode(k.k, ptrs, p, entry)
 701		if (p.ptr.dev < c->sb.nr_devices && c->devs[p.ptr.dev])
 702			durability += bch2_extent_ptr_durability(c, &p);
 703
 704	return durability;
 705}
 706
 707void bch2_bkey_extent_entry_drop(struct bkey_i *k, union bch_extent_entry *entry)
 708{
 709	union bch_extent_entry *end = bkey_val_end(bkey_i_to_s(k));
 710	union bch_extent_entry *next = extent_entry_next(entry);
 711
 712	memmove_u64s(entry, next, (u64 *) end - (u64 *) next);
 713	k->k.u64s -= extent_entry_u64s(entry);
 714}
 715
 716void bch2_extent_ptr_decoded_append(struct bkey_i *k,
 717				    struct extent_ptr_decoded *p)
 718{
 719	struct bkey_ptrs ptrs = bch2_bkey_ptrs(bkey_i_to_s(k));
 720	struct bch_extent_crc_unpacked crc =
 721		bch2_extent_crc_unpack(&k->k, NULL);
 722	union bch_extent_entry *pos;
 723
 724	if (!bch2_crc_unpacked_cmp(crc, p->crc)) {
 725		pos = ptrs.start;
 726		goto found;
 727	}
 728
 729	bkey_for_each_crc(&k->k, ptrs, crc, pos)
 730		if (!bch2_crc_unpacked_cmp(crc, p->crc)) {
 731			pos = extent_entry_next(pos);
 732			goto found;
 733		}
 734
 735	bch2_extent_crc_append(k, p->crc);
 736	pos = bkey_val_end(bkey_i_to_s(k));
 737found:
 738	p->ptr.type = 1 << BCH_EXTENT_ENTRY_ptr;
 739	__extent_entry_insert(k, pos, to_entry(&p->ptr));
 740
 741	if (p->has_ec) {
 742		p->ec.type = 1 << BCH_EXTENT_ENTRY_stripe_ptr;
 743		__extent_entry_insert(k, pos, to_entry(&p->ec));
 744	}
 745}
 746
 747static union bch_extent_entry *extent_entry_prev(struct bkey_ptrs ptrs,
 748					  union bch_extent_entry *entry)
 749{
 750	union bch_extent_entry *i = ptrs.start;
 751
 752	if (i == entry)
 753		return NULL;
 754
 755	while (extent_entry_next(i) != entry)
 756		i = extent_entry_next(i);
 757	return i;
 758}
 759
 760/*
 761 * Returns pointer to the next entry after the one being dropped:
 762 */
 763union bch_extent_entry *bch2_bkey_drop_ptr_noerror(struct bkey_s k,
 764						   struct bch_extent_ptr *ptr)
 765{
 766	struct bkey_ptrs ptrs = bch2_bkey_ptrs(k);
 767	union bch_extent_entry *entry = to_entry(ptr), *next;
 768	union bch_extent_entry *ret = entry;
 769	bool drop_crc = true;
 770
 771	EBUG_ON(ptr < &ptrs.start->ptr ||
 772		ptr >= &ptrs.end->ptr);
 773	EBUG_ON(ptr->type != 1 << BCH_EXTENT_ENTRY_ptr);
 774
 775	for (next = extent_entry_next(entry);
 776	     next != ptrs.end;
 777	     next = extent_entry_next(next)) {
 778		if (extent_entry_is_crc(next)) {
 779			break;
 780		} else if (extent_entry_is_ptr(next)) {
 781			drop_crc = false;
 782			break;
 783		}
 784	}
 785
 786	extent_entry_drop(k, entry);
 787
 788	while ((entry = extent_entry_prev(ptrs, entry))) {
 789		if (extent_entry_is_ptr(entry))
 790			break;
 791
 792		if ((extent_entry_is_crc(entry) && drop_crc) ||
 793		    extent_entry_is_stripe_ptr(entry)) {
 794			ret = (void *) ret - extent_entry_bytes(entry);
 795			extent_entry_drop(k, entry);
 796		}
 797	}
 798
 799	return ret;
 800}
 801
 802union bch_extent_entry *bch2_bkey_drop_ptr(struct bkey_s k,
 803					   struct bch_extent_ptr *ptr)
 804{
 805	bool have_dirty = bch2_bkey_dirty_devs(k.s_c).nr;
 806	union bch_extent_entry *ret =
 807		bch2_bkey_drop_ptr_noerror(k, ptr);
 808
 809	/*
 810	 * If we deleted all the dirty pointers and there's still cached
 811	 * pointers, we could set the cached pointers to dirty if they're not
 812	 * stale - but to do that correctly we'd need to grab an open_bucket
 813	 * reference so that we don't race with bucket reuse:
 814	 */
 815	if (have_dirty &&
 816	    !bch2_bkey_dirty_devs(k.s_c).nr) {
 817		k.k->type = KEY_TYPE_error;
 818		set_bkey_val_u64s(k.k, 0);
 819		ret = NULL;
 820	} else if (!bch2_bkey_nr_ptrs(k.s_c)) {
 821		k.k->type = KEY_TYPE_deleted;
 822		set_bkey_val_u64s(k.k, 0);
 823		ret = NULL;
 824	}
 825
 826	return ret;
 827}
 828
 829void bch2_bkey_drop_device(struct bkey_s k, unsigned dev)
 830{
 831	struct bch_extent_ptr *ptr;
 832
 833	bch2_bkey_drop_ptrs(k, ptr, ptr->dev == dev);
 834}
 835
 836void bch2_bkey_drop_device_noerror(struct bkey_s k, unsigned dev)
 837{
 838	struct bch_extent_ptr *ptr = bch2_bkey_has_device(k, dev);
 839
 840	if (ptr)
 841		bch2_bkey_drop_ptr_noerror(k, ptr);
 842}
 843
 844const struct bch_extent_ptr *bch2_bkey_has_device_c(struct bkey_s_c k, unsigned dev)
 845{
 846	struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
 847
 848	bkey_for_each_ptr(ptrs, ptr)
 849		if (ptr->dev == dev)
 850			return ptr;
 851
 852	return NULL;
 853}
 854
 855bool bch2_bkey_has_target(struct bch_fs *c, struct bkey_s_c k, unsigned target)
 856{
 857	struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
 858
 859	bkey_for_each_ptr(ptrs, ptr)
 860		if (bch2_dev_in_target(c, ptr->dev, target) &&
 861		    (!ptr->cached ||
 862		     !ptr_stale(bch_dev_bkey_exists(c, ptr->dev), ptr)))
 863			return true;
 864
 865	return false;
 866}
 867
 868bool bch2_bkey_matches_ptr(struct bch_fs *c, struct bkey_s_c k,
 869			   struct bch_extent_ptr m, u64 offset)
 870{
 871	struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
 872	const union bch_extent_entry *entry;
 873	struct extent_ptr_decoded p;
 874
 875	bkey_for_each_ptr_decode(k.k, ptrs, p, entry)
 876		if (p.ptr.dev	== m.dev &&
 877		    p.ptr.gen	== m.gen &&
 878		    (s64) p.ptr.offset + p.crc.offset - bkey_start_offset(k.k) ==
 879		    (s64) m.offset  - offset)
 880			return true;
 881
 882	return false;
 883}
 884
 885/*
 886 * Returns true if two extents refer to the same data:
 887 */
 888bool bch2_extents_match(struct bkey_s_c k1, struct bkey_s_c k2)
 889{
 890	if (k1.k->type != k2.k->type)
 891		return false;
 892
 893	if (bkey_extent_is_direct_data(k1.k)) {
 894		struct bkey_ptrs_c ptrs1 = bch2_bkey_ptrs_c(k1);
 895		struct bkey_ptrs_c ptrs2 = bch2_bkey_ptrs_c(k2);
 896		const union bch_extent_entry *entry1, *entry2;
 897		struct extent_ptr_decoded p1, p2;
 898
 899		if (bkey_extent_is_unwritten(k1) != bkey_extent_is_unwritten(k2))
 900			return false;
 901
 902		bkey_for_each_ptr_decode(k1.k, ptrs1, p1, entry1)
 903			bkey_for_each_ptr_decode(k2.k, ptrs2, p2, entry2)
 904				if (p1.ptr.dev		== p2.ptr.dev &&
 905				    p1.ptr.gen		== p2.ptr.gen &&
 906				    (s64) p1.ptr.offset + p1.crc.offset - bkey_start_offset(k1.k) ==
 907				    (s64) p2.ptr.offset + p2.crc.offset - bkey_start_offset(k2.k))
 908					return true;
 909
 910		return false;
 911	} else {
 912		/* KEY_TYPE_deleted, etc. */
 913		return true;
 914	}
 915}
 916
 917struct bch_extent_ptr *
 918bch2_extent_has_ptr(struct bkey_s_c k1, struct extent_ptr_decoded p1, struct bkey_s k2)
 919{
 920	struct bkey_ptrs ptrs2 = bch2_bkey_ptrs(k2);
 921	union bch_extent_entry *entry2;
 922	struct extent_ptr_decoded p2;
 923
 924	bkey_for_each_ptr_decode(k2.k, ptrs2, p2, entry2)
 925		if (p1.ptr.dev		== p2.ptr.dev &&
 926		    p1.ptr.gen		== p2.ptr.gen &&
 927		    (s64) p1.ptr.offset + p1.crc.offset - bkey_start_offset(k1.k) ==
 928		    (s64) p2.ptr.offset + p2.crc.offset - bkey_start_offset(k2.k))
 929			return &entry2->ptr;
 930
 931	return NULL;
 932}
 933
 934void bch2_extent_ptr_set_cached(struct bkey_s k, struct bch_extent_ptr *ptr)
 935{
 936	struct bkey_ptrs ptrs = bch2_bkey_ptrs(k);
 937	union bch_extent_entry *entry;
 938	union bch_extent_entry *ec = NULL;
 939
 940	bkey_extent_entry_for_each(ptrs, entry) {
 941		if (&entry->ptr == ptr) {
 942			ptr->cached = true;
 943			if (ec)
 944				extent_entry_drop(k, ec);
 945			return;
 946		}
 947
 948		if (extent_entry_is_stripe_ptr(entry))
 949			ec = entry;
 950		else if (extent_entry_is_ptr(entry))
 951			ec = NULL;
 952	}
 953
 954	BUG();
 955}
 956
 957/*
 958 * bch_extent_normalize - clean up an extent, dropping stale pointers etc.
 959 *
 960 * Returns true if @k should be dropped entirely
 961 *
 962 * For existing keys, only called when btree nodes are being rewritten, not when
 963 * they're merely being compacted/resorted in memory.
 964 */
 965bool bch2_extent_normalize(struct bch_fs *c, struct bkey_s k)
 966{
 967	struct bch_extent_ptr *ptr;
 968
 969	bch2_bkey_drop_ptrs(k, ptr,
 970		ptr->cached &&
 971		ptr_stale(bch_dev_bkey_exists(c, ptr->dev), ptr));
 972
 973	return bkey_deleted(k.k);
 974}
 975
 976void bch2_bkey_ptrs_to_text(struct printbuf *out, struct bch_fs *c,
 977			    struct bkey_s_c k)
 978{
 979	struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
 980	const union bch_extent_entry *entry;
 981	bool first = true;
 982
 983	if (c)
 984		prt_printf(out, "durability: %u ", bch2_bkey_durability_safe(c, k));
 985
 986	bkey_extent_entry_for_each(ptrs, entry) {
 987		if (!first)
 988			prt_printf(out, " ");
 989
 990		switch (__extent_entry_type(entry)) {
 991		case BCH_EXTENT_ENTRY_ptr: {
 992			const struct bch_extent_ptr *ptr = entry_to_ptr(entry);
 993			struct bch_dev *ca = c && ptr->dev < c->sb.nr_devices && c->devs[ptr->dev]
 994				? bch_dev_bkey_exists(c, ptr->dev)
 995				: NULL;
 996
 997			if (!ca) {
 998				prt_printf(out, "ptr: %u:%llu gen %u%s", ptr->dev,
 999				       (u64) ptr->offset, ptr->gen,
1000				       ptr->cached ? " cached" : "");
1001			} else {
1002				u32 offset;
1003				u64 b = sector_to_bucket_and_offset(ca, ptr->offset, &offset);
1004
1005				prt_printf(out, "ptr: %u:%llu:%u gen %u",
1006					   ptr->dev, b, offset, ptr->gen);
1007				if (ptr->cached)
1008					prt_str(out, " cached");
1009				if (ptr->unwritten)
1010					prt_str(out, " unwritten");
1011				if (ca && ptr_stale(ca, ptr))
1012					prt_printf(out, " stale");
1013			}
1014			break;
1015		}
1016		case BCH_EXTENT_ENTRY_crc32:
1017		case BCH_EXTENT_ENTRY_crc64:
1018		case BCH_EXTENT_ENTRY_crc128: {
1019			struct bch_extent_crc_unpacked crc =
1020				bch2_extent_crc_unpack(k.k, entry_to_crc(entry));
1021
1022			prt_printf(out, "crc: c_size %u size %u offset %u nonce %u csum %s compress ",
1023			       crc.compressed_size,
1024			       crc.uncompressed_size,
1025			       crc.offset, crc.nonce,
1026			       bch2_csum_types[crc.csum_type]);
1027			bch2_prt_compression_type(out, crc.compression_type);
1028			break;
1029		}
1030		case BCH_EXTENT_ENTRY_stripe_ptr: {
1031			const struct bch_extent_stripe_ptr *ec = &entry->stripe_ptr;
1032
1033			prt_printf(out, "ec: idx %llu block %u",
1034			       (u64) ec->idx, ec->block);
1035			break;
1036		}
1037		case BCH_EXTENT_ENTRY_rebalance: {
1038			const struct bch_extent_rebalance *r = &entry->rebalance;
1039
1040			prt_str(out, "rebalance: target ");
1041			if (c)
1042				bch2_target_to_text(out, c, r->target);
1043			else
1044				prt_printf(out, "%u", r->target);
1045			prt_str(out, " compression ");
1046			bch2_compression_opt_to_text(out, r->compression);
1047			break;
1048		}
1049		default:
1050			prt_printf(out, "(invalid extent entry %.16llx)", *((u64 *) entry));
1051			return;
1052		}
1053
1054		first = false;
1055	}
1056}
1057
1058static int extent_ptr_invalid(struct bch_fs *c,
1059			      struct bkey_s_c k,
1060			      enum bkey_invalid_flags flags,
1061			      const struct bch_extent_ptr *ptr,
1062			      unsigned size_ondisk,
1063			      bool metadata,
1064			      struct printbuf *err)
1065{
1066	struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
1067	u64 bucket;
1068	u32 bucket_offset;
1069	struct bch_dev *ca;
1070	int ret = 0;
1071
1072	if (!bch2_dev_exists2(c, ptr->dev)) {
1073		/*
1074		 * If we're in the write path this key might have already been
1075		 * overwritten, and we could be seeing a device that doesn't
1076		 * exist anymore due to racing with device removal:
1077		 */
1078		if (flags & BKEY_INVALID_WRITE)
1079			return 0;
1080
1081		bkey_fsck_err(c, err, ptr_to_invalid_device,
1082			   "pointer to invalid device (%u)", ptr->dev);
1083	}
1084
1085	ca = bch_dev_bkey_exists(c, ptr->dev);
1086	bkey_for_each_ptr(ptrs, ptr2)
1087		bkey_fsck_err_on(ptr != ptr2 && ptr->dev == ptr2->dev, c, err,
1088				 ptr_to_duplicate_device,
1089				 "multiple pointers to same device (%u)", ptr->dev);
1090
1091	bucket = sector_to_bucket_and_offset(ca, ptr->offset, &bucket_offset);
1092
1093	bkey_fsck_err_on(bucket >= ca->mi.nbuckets, c, err,
1094			 ptr_after_last_bucket,
1095			 "pointer past last bucket (%llu > %llu)", bucket, ca->mi.nbuckets);
1096	bkey_fsck_err_on(ptr->offset < bucket_to_sector(ca, ca->mi.first_bucket), c, err,
1097			 ptr_before_first_bucket,
1098			 "pointer before first bucket (%llu < %u)", bucket, ca->mi.first_bucket);
1099	bkey_fsck_err_on(bucket_offset + size_ondisk > ca->mi.bucket_size, c, err,
1100			 ptr_spans_multiple_buckets,
1101			 "pointer spans multiple buckets (%u + %u > %u)",
1102		       bucket_offset, size_ondisk, ca->mi.bucket_size);
1103fsck_err:
1104	return ret;
1105}
1106
1107int bch2_bkey_ptrs_invalid(struct bch_fs *c, struct bkey_s_c k,
1108			   enum bkey_invalid_flags flags,
1109			   struct printbuf *err)
1110{
1111	struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
1112	const union bch_extent_entry *entry;
1113	struct bch_extent_crc_unpacked crc;
1114	unsigned size_ondisk = k.k->size;
1115	unsigned nonce = UINT_MAX;
1116	unsigned nr_ptrs = 0;
1117	bool have_written = false, have_unwritten = false, have_ec = false, crc_since_last_ptr = false;
1118	int ret = 0;
1119
1120	if (bkey_is_btree_ptr(k.k))
1121		size_ondisk = btree_sectors(c);
1122
1123	bkey_extent_entry_for_each(ptrs, entry) {
1124		bkey_fsck_err_on(__extent_entry_type(entry) >= BCH_EXTENT_ENTRY_MAX, c, err,
1125			extent_ptrs_invalid_entry,
1126			"invalid extent entry type (got %u, max %u)",
1127			__extent_entry_type(entry), BCH_EXTENT_ENTRY_MAX);
1128
1129		bkey_fsck_err_on(bkey_is_btree_ptr(k.k) &&
1130				 !extent_entry_is_ptr(entry), c, err,
1131				 btree_ptr_has_non_ptr,
1132				 "has non ptr field");
1133
1134		switch (extent_entry_type(entry)) {
1135		case BCH_EXTENT_ENTRY_ptr:
1136			ret = extent_ptr_invalid(c, k, flags, &entry->ptr,
1137						 size_ondisk, false, err);
1138			if (ret)
1139				return ret;
1140
1141			bkey_fsck_err_on(entry->ptr.cached && have_ec, c, err,
1142					 ptr_cached_and_erasure_coded,
1143					 "cached, erasure coded ptr");
1144
1145			if (!entry->ptr.unwritten)
1146				have_written = true;
1147			else
1148				have_unwritten = true;
1149
1150			have_ec = false;
1151			crc_since_last_ptr = false;
1152			nr_ptrs++;
1153			break;
1154		case BCH_EXTENT_ENTRY_crc32:
1155		case BCH_EXTENT_ENTRY_crc64:
1156		case BCH_EXTENT_ENTRY_crc128:
1157			crc = bch2_extent_crc_unpack(k.k, entry_to_crc(entry));
1158
1159			bkey_fsck_err_on(crc.offset + crc.live_size > crc.uncompressed_size, c, err,
1160					 ptr_crc_uncompressed_size_too_small,
1161					 "checksum offset + key size > uncompressed size");
1162			bkey_fsck_err_on(!bch2_checksum_type_valid(c, crc.csum_type), c, err,
1163					 ptr_crc_csum_type_unknown,
1164					 "invalid checksum type");
1165			bkey_fsck_err_on(crc.compression_type >= BCH_COMPRESSION_TYPE_NR, c, err,
1166					 ptr_crc_compression_type_unknown,
1167					 "invalid compression type");
1168
1169			if (bch2_csum_type_is_encryption(crc.csum_type)) {
1170				if (nonce == UINT_MAX)
1171					nonce = crc.offset + crc.nonce;
1172				else if (nonce != crc.offset + crc.nonce)
1173					bkey_fsck_err(c, err, ptr_crc_nonce_mismatch,
1174						      "incorrect nonce");
1175			}
1176
1177			bkey_fsck_err_on(crc_since_last_ptr, c, err,
1178					 ptr_crc_redundant,
1179					 "redundant crc entry");
1180			crc_since_last_ptr = true;
1181
1182			bkey_fsck_err_on(crc_is_encoded(crc) &&
1183					 (crc.uncompressed_size > c->opts.encoded_extent_max >> 9) &&
1184					 (flags & (BKEY_INVALID_WRITE|BKEY_INVALID_COMMIT)), c, err,
1185					 ptr_crc_uncompressed_size_too_big,
1186					 "too large encoded extent");
1187
1188			size_ondisk = crc.compressed_size;
1189			break;
1190		case BCH_EXTENT_ENTRY_stripe_ptr:
1191			bkey_fsck_err_on(have_ec, c, err,
1192					 ptr_stripe_redundant,
1193					 "redundant stripe entry");
1194			have_ec = true;
1195			break;
1196		case BCH_EXTENT_ENTRY_rebalance: {
1197			const struct bch_extent_rebalance *r = &entry->rebalance;
1198
1199			if (!bch2_compression_opt_valid(r->compression)) {
1200				struct bch_compression_opt opt = __bch2_compression_decode(r->compression);
1201				prt_printf(err, "invalid compression opt %u:%u",
1202					   opt.type, opt.level);
1203				return -BCH_ERR_invalid_bkey;
1204			}
1205			break;
1206		}
1207		}
1208	}
1209
1210	bkey_fsck_err_on(!nr_ptrs, c, err,
1211			 extent_ptrs_no_ptrs,
1212			 "no ptrs");
1213	bkey_fsck_err_on(nr_ptrs > BCH_BKEY_PTRS_MAX, c, err,
1214			 extent_ptrs_too_many_ptrs,
1215			 "too many ptrs: %u > %u", nr_ptrs, BCH_BKEY_PTRS_MAX);
1216	bkey_fsck_err_on(have_written && have_unwritten, c, err,
1217			 extent_ptrs_written_and_unwritten,
1218			 "extent with unwritten and written ptrs");
1219	bkey_fsck_err_on(k.k->type != KEY_TYPE_extent && have_unwritten, c, err,
1220			 extent_ptrs_unwritten,
1221			 "has unwritten ptrs");
1222	bkey_fsck_err_on(crc_since_last_ptr, c, err,
1223			 extent_ptrs_redundant_crc,
1224			 "redundant crc entry");
1225	bkey_fsck_err_on(have_ec, c, err,
1226			 extent_ptrs_redundant_stripe,
1227			 "redundant stripe entry");
1228fsck_err:
1229	return ret;
1230}
1231
1232void bch2_ptr_swab(struct bkey_s k)
1233{
1234	struct bkey_ptrs ptrs = bch2_bkey_ptrs(k);
1235	union bch_extent_entry *entry;
1236	u64 *d;
1237
1238	for (d =  (u64 *) ptrs.start;
1239	     d != (u64 *) ptrs.end;
1240	     d++)
1241		*d = swab64(*d);
1242
1243	for (entry = ptrs.start;
1244	     entry < ptrs.end;
1245	     entry = extent_entry_next(entry)) {
1246		switch (extent_entry_type(entry)) {
1247		case BCH_EXTENT_ENTRY_ptr:
1248			break;
1249		case BCH_EXTENT_ENTRY_crc32:
1250			entry->crc32.csum = swab32(entry->crc32.csum);
1251			break;
1252		case BCH_EXTENT_ENTRY_crc64:
1253			entry->crc64.csum_hi = swab16(entry->crc64.csum_hi);
1254			entry->crc64.csum_lo = swab64(entry->crc64.csum_lo);
1255			break;
1256		case BCH_EXTENT_ENTRY_crc128:
1257			entry->crc128.csum.hi = (__force __le64)
1258				swab64((__force u64) entry->crc128.csum.hi);
1259			entry->crc128.csum.lo = (__force __le64)
1260				swab64((__force u64) entry->crc128.csum.lo);
1261			break;
1262		case BCH_EXTENT_ENTRY_stripe_ptr:
1263			break;
1264		case BCH_EXTENT_ENTRY_rebalance:
1265			break;
1266		}
1267	}
1268}
1269
1270const struct bch_extent_rebalance *bch2_bkey_rebalance_opts(struct bkey_s_c k)
1271{
1272	struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
1273	const union bch_extent_entry *entry;
1274
1275	bkey_extent_entry_for_each(ptrs, entry)
1276		if (__extent_entry_type(entry) == BCH_EXTENT_ENTRY_rebalance)
1277			return &entry->rebalance;
1278
1279	return NULL;
1280}
1281
1282unsigned bch2_bkey_ptrs_need_rebalance(struct bch_fs *c, struct bkey_s_c k,
1283				       unsigned target, unsigned compression)
1284{
1285	struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
1286	unsigned rewrite_ptrs = 0;
1287
1288	if (compression) {
1289		unsigned compression_type = bch2_compression_opt_to_type(compression);
1290		const union bch_extent_entry *entry;
1291		struct extent_ptr_decoded p;
1292		unsigned i = 0;
1293
1294		bkey_for_each_ptr_decode(k.k, ptrs, p, entry) {
1295			if (p.crc.compression_type == BCH_COMPRESSION_TYPE_incompressible ||
1296			    p.ptr.unwritten) {
1297				rewrite_ptrs = 0;
1298				goto incompressible;
1299			}
1300
1301			if (!p.ptr.cached && p.crc.compression_type != compression_type)
1302				rewrite_ptrs |= 1U << i;
1303			i++;
1304		}
1305	}
1306incompressible:
1307	if (target && bch2_target_accepts_data(c, BCH_DATA_user, target)) {
1308		unsigned i = 0;
1309
1310		bkey_for_each_ptr(ptrs, ptr) {
1311			if (!ptr->cached && !bch2_dev_in_target(c, ptr->dev, target))
1312				rewrite_ptrs |= 1U << i;
1313			i++;
1314		}
1315	}
1316
1317	return rewrite_ptrs;
1318}
1319
1320bool bch2_bkey_needs_rebalance(struct bch_fs *c, struct bkey_s_c k)
1321{
1322	const struct bch_extent_rebalance *r = bch2_bkey_rebalance_opts(k);
1323
1324	/*
1325	 * If it's an indirect extent, we don't delete the rebalance entry when
1326	 * done so that we know what options were applied - check if it still
1327	 * needs work done:
1328	 */
1329	if (r &&
1330	    k.k->type == KEY_TYPE_reflink_v &&
1331	    !bch2_bkey_ptrs_need_rebalance(c, k, r->target, r->compression))
1332		r = NULL;
1333
1334	return r != NULL;
1335}
1336
1337int bch2_bkey_set_needs_rebalance(struct bch_fs *c, struct bkey_i *_k,
1338				  struct bch_io_opts *opts)
1339{
1340	struct bkey_s k = bkey_i_to_s(_k);
1341	struct bch_extent_rebalance *r;
1342	unsigned target = opts->background_target;
1343	unsigned compression = background_compression(*opts);
1344	bool needs_rebalance;
1345
1346	if (!bkey_extent_is_direct_data(k.k))
1347		return 0;
1348
1349	/* get existing rebalance entry: */
1350	r = (struct bch_extent_rebalance *) bch2_bkey_rebalance_opts(k.s_c);
1351	if (r) {
1352		if (k.k->type == KEY_TYPE_reflink_v) {
1353			/*
1354			 * indirect extents: existing options take precedence,
1355			 * so that we don't move extents back and forth if
1356			 * they're referenced by different inodes with different
1357			 * options:
1358			 */
1359			if (r->target)
1360				target = r->target;
1361			if (r->compression)
1362				compression = r->compression;
1363		}
1364
1365		r->target	= target;
1366		r->compression	= compression;
1367	}
1368
1369	needs_rebalance = bch2_bkey_ptrs_need_rebalance(c, k.s_c, target, compression);
1370
1371	if (needs_rebalance && !r) {
1372		union bch_extent_entry *new = bkey_val_end(k);
1373
1374		new->rebalance.type		= 1U << BCH_EXTENT_ENTRY_rebalance;
1375		new->rebalance.compression	= compression;
1376		new->rebalance.target		= target;
1377		new->rebalance.unused		= 0;
1378		k.k->u64s += extent_entry_u64s(new);
1379	} else if (!needs_rebalance && r && k.k->type != KEY_TYPE_reflink_v) {
1380		/*
1381		 * For indirect extents, don't delete the rebalance entry when
1382		 * we're finished so that we know we specifically moved it or
1383		 * compressed it to its current location/compression type
1384		 */
1385		extent_entry_drop(k, (union bch_extent_entry *) r);
1386	}
1387
1388	return 0;
1389}
1390
1391/* Generic extent code: */
1392
1393int bch2_cut_front_s(struct bpos where, struct bkey_s k)
1394{
1395	unsigned new_val_u64s = bkey_val_u64s(k.k);
1396	int val_u64s_delta;
1397	u64 sub;
1398
1399	if (bkey_le(where, bkey_start_pos(k.k)))
1400		return 0;
1401
1402	EBUG_ON(bkey_gt(where, k.k->p));
1403
1404	sub = where.offset - bkey_start_offset(k.k);
1405
1406	k.k->size -= sub;
1407
1408	if (!k.k->size) {
1409		k.k->type = KEY_TYPE_deleted;
1410		new_val_u64s = 0;
1411	}
1412
1413	switch (k.k->type) {
1414	case KEY_TYPE_extent:
1415	case KEY_TYPE_reflink_v: {
1416		struct bkey_ptrs ptrs = bch2_bkey_ptrs(k);
1417		union bch_extent_entry *entry;
1418		bool seen_crc = false;
1419
1420		bkey_extent_entry_for_each(ptrs, entry) {
1421			switch (extent_entry_type(entry)) {
1422			case BCH_EXTENT_ENTRY_ptr:
1423				if (!seen_crc)
1424					entry->ptr.offset += sub;
1425				break;
1426			case BCH_EXTENT_ENTRY_crc32:
1427				entry->crc32.offset += sub;
1428				break;
1429			case BCH_EXTENT_ENTRY_crc64:
1430				entry->crc64.offset += sub;
1431				break;
1432			case BCH_EXTENT_ENTRY_crc128:
1433				entry->crc128.offset += sub;
1434				break;
1435			case BCH_EXTENT_ENTRY_stripe_ptr:
1436				break;
1437			case BCH_EXTENT_ENTRY_rebalance:
1438				break;
1439			}
1440
1441			if (extent_entry_is_crc(entry))
1442				seen_crc = true;
1443		}
1444
1445		break;
1446	}
1447	case KEY_TYPE_reflink_p: {
1448		struct bkey_s_reflink_p p = bkey_s_to_reflink_p(k);
1449
1450		le64_add_cpu(&p.v->idx, sub);
1451		break;
1452	}
1453	case KEY_TYPE_inline_data:
1454	case KEY_TYPE_indirect_inline_data: {
1455		void *p = bkey_inline_data_p(k);
1456		unsigned bytes = bkey_inline_data_bytes(k.k);
1457
1458		sub = min_t(u64, sub << 9, bytes);
1459
1460		memmove(p, p + sub, bytes - sub);
1461
1462		new_val_u64s -= sub >> 3;
1463		break;
1464	}
1465	}
1466
1467	val_u64s_delta = bkey_val_u64s(k.k) - new_val_u64s;
1468	BUG_ON(val_u64s_delta < 0);
1469
1470	set_bkey_val_u64s(k.k, new_val_u64s);
1471	memset(bkey_val_end(k), 0, val_u64s_delta * sizeof(u64));
1472	return -val_u64s_delta;
1473}
1474
1475int bch2_cut_back_s(struct bpos where, struct bkey_s k)
1476{
1477	unsigned new_val_u64s = bkey_val_u64s(k.k);
1478	int val_u64s_delta;
1479	u64 len = 0;
1480
1481	if (bkey_ge(where, k.k->p))
1482		return 0;
1483
1484	EBUG_ON(bkey_lt(where, bkey_start_pos(k.k)));
1485
1486	len = where.offset - bkey_start_offset(k.k);
1487
1488	k.k->p.offset = where.offset;
1489	k.k->size = len;
1490
1491	if (!len) {
1492		k.k->type = KEY_TYPE_deleted;
1493		new_val_u64s = 0;
1494	}
1495
1496	switch (k.k->type) {
1497	case KEY_TYPE_inline_data:
1498	case KEY_TYPE_indirect_inline_data:
1499		new_val_u64s = (bkey_inline_data_offset(k.k) +
1500				min(bkey_inline_data_bytes(k.k), k.k->size << 9)) >> 3;
1501		break;
1502	}
1503
1504	val_u64s_delta = bkey_val_u64s(k.k) - new_val_u64s;
1505	BUG_ON(val_u64s_delta < 0);
1506
1507	set_bkey_val_u64s(k.k, new_val_u64s);
1508	memset(bkey_val_end(k), 0, val_u64s_delta * sizeof(u64));
1509	return -val_u64s_delta;
1510}