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1// SPDX-License-Identifier: GPL-2.02 3#include "bcachefs.h"4#include "alloc_foreground.h"5#include "bkey_buf.h"6#include "btree_update.h"7#include "buckets.h"8#include "compress.h"9#include "data_update.h"10#include "disk_groups.h"11#include "ec.h"12#include "error.h"13#include "extents.h"14#include "io_write.h"15#include "keylist.h"16#include "move.h"17#include "nocow_locking.h"18#include "rebalance.h"19#include "snapshot.h"20#include "subvolume.h"21#include "trace.h"22 23static void bkey_put_dev_refs(struct bch_fs *c, struct bkey_s_c k)24{25	struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);26 27	bkey_for_each_ptr(ptrs, ptr)28		bch2_dev_put(bch2_dev_have_ref(c, ptr->dev));29}30 31static bool bkey_get_dev_refs(struct bch_fs *c, struct bkey_s_c k)32{33	struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);34 35	bkey_for_each_ptr(ptrs, ptr) {36		if (!bch2_dev_tryget(c, ptr->dev)) {37			bkey_for_each_ptr(ptrs, ptr2) {38				if (ptr2 == ptr)39					break;40				bch2_dev_put(bch2_dev_have_ref(c, ptr2->dev));41			}42			return false;43		}44	}45	return true;46}47 48static void bkey_nocow_unlock(struct bch_fs *c, struct bkey_s_c k)49{50	struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);51 52	bkey_for_each_ptr(ptrs, ptr) {53		struct bch_dev *ca = bch2_dev_have_ref(c, ptr->dev);54		struct bpos bucket = PTR_BUCKET_POS(ca, ptr);55 56		bch2_bucket_nocow_unlock(&c->nocow_locks, bucket, 0);57	}58}59 60static bool bkey_nocow_lock(struct bch_fs *c, struct moving_context *ctxt, struct bkey_s_c k)61{62	struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);63 64	bkey_for_each_ptr(ptrs, ptr) {65		struct bch_dev *ca = bch2_dev_have_ref(c, ptr->dev);66		struct bpos bucket = PTR_BUCKET_POS(ca, ptr);67 68		if (ctxt) {69			bool locked;70 71			move_ctxt_wait_event(ctxt,72				(locked = bch2_bucket_nocow_trylock(&c->nocow_locks, bucket, 0)) ||73				list_empty(&ctxt->ios));74 75			if (!locked)76				bch2_bucket_nocow_lock(&c->nocow_locks, bucket, 0);77		} else {78			if (!bch2_bucket_nocow_trylock(&c->nocow_locks, bucket, 0)) {79				bkey_for_each_ptr(ptrs, ptr2) {80					if (ptr2 == ptr)81						break;82 83					ca = bch2_dev_have_ref(c, ptr2->dev);84					bucket = PTR_BUCKET_POS(ca, ptr2);85					bch2_bucket_nocow_unlock(&c->nocow_locks, bucket, 0);86				}87				return false;88			}89		}90	}91	return true;92}93 94static void trace_move_extent_finish2(struct bch_fs *c, struct bkey_s_c k)95{96	if (trace_move_extent_finish_enabled()) {97		struct printbuf buf = PRINTBUF;98 99		bch2_bkey_val_to_text(&buf, c, k);100		trace_move_extent_finish(c, buf.buf);101		printbuf_exit(&buf);102	}103}104 105static void trace_move_extent_fail2(struct data_update *m,106			 struct bkey_s_c new,107			 struct bkey_s_c wrote,108			 struct bkey_i *insert,109			 const char *msg)110{111	struct bch_fs *c = m->op.c;112	struct bkey_s_c old = bkey_i_to_s_c(m->k.k);113	const union bch_extent_entry *entry;114	struct bch_extent_ptr *ptr;115	struct extent_ptr_decoded p;116	struct printbuf buf = PRINTBUF;117	unsigned i, rewrites_found = 0;118 119	if (!trace_move_extent_fail_enabled())120		return;121 122	prt_str(&buf, msg);123 124	if (insert) {125		i = 0;126		bkey_for_each_ptr_decode(old.k, bch2_bkey_ptrs_c(old), p, entry) {127			if (((1U << i) & m->data_opts.rewrite_ptrs) &&128			    (ptr = bch2_extent_has_ptr(old, p, bkey_i_to_s(insert))) &&129			    !ptr->cached)130				rewrites_found |= 1U << i;131			i++;132		}133	}134 135	prt_printf(&buf, "\nrewrite ptrs:   %u%u%u%u",136		   (m->data_opts.rewrite_ptrs & (1 << 0)) != 0,137		   (m->data_opts.rewrite_ptrs & (1 << 1)) != 0,138		   (m->data_opts.rewrite_ptrs & (1 << 2)) != 0,139		   (m->data_opts.rewrite_ptrs & (1 << 3)) != 0);140 141	prt_printf(&buf, "\nrewrites found: %u%u%u%u",142		   (rewrites_found & (1 << 0)) != 0,143		   (rewrites_found & (1 << 1)) != 0,144		   (rewrites_found & (1 << 2)) != 0,145		   (rewrites_found & (1 << 3)) != 0);146 147	prt_str(&buf, "\nold:    ");148	bch2_bkey_val_to_text(&buf, c, old);149 150	prt_str(&buf, "\nnew:    ");151	bch2_bkey_val_to_text(&buf, c, new);152 153	prt_str(&buf, "\nwrote:  ");154	bch2_bkey_val_to_text(&buf, c, wrote);155 156	if (insert) {157		prt_str(&buf, "\ninsert: ");158		bch2_bkey_val_to_text(&buf, c, bkey_i_to_s_c(insert));159	}160 161	trace_move_extent_fail(c, buf.buf);162	printbuf_exit(&buf);163}164 165static int __bch2_data_update_index_update(struct btree_trans *trans,166					   struct bch_write_op *op)167{168	struct bch_fs *c = op->c;169	struct btree_iter iter;170	struct data_update *m =171		container_of(op, struct data_update, op);172	struct keylist *keys = &op->insert_keys;173	struct bkey_buf _new, _insert;174	int ret = 0;175 176	bch2_bkey_buf_init(&_new);177	bch2_bkey_buf_init(&_insert);178	bch2_bkey_buf_realloc(&_insert, c, U8_MAX);179 180	bch2_trans_iter_init(trans, &iter, m->btree_id,181			     bkey_start_pos(&bch2_keylist_front(keys)->k),182			     BTREE_ITER_slots|BTREE_ITER_intent);183 184	while (1) {185		struct bkey_s_c k;186		struct bkey_s_c old = bkey_i_to_s_c(m->k.k);187		struct bkey_i *insert = NULL;188		struct bkey_i_extent *new;189		const union bch_extent_entry *entry_c;190		union bch_extent_entry *entry;191		struct extent_ptr_decoded p;192		struct bch_extent_ptr *ptr;193		const struct bch_extent_ptr *ptr_c;194		struct bpos next_pos;195		bool should_check_enospc;196		s64 i_sectors_delta = 0, disk_sectors_delta = 0;197		unsigned rewrites_found = 0, durability, i;198 199		bch2_trans_begin(trans);200 201		k = bch2_btree_iter_peek_slot(&iter);202		ret = bkey_err(k);203		if (ret)204			goto err;205 206		new = bkey_i_to_extent(bch2_keylist_front(keys));207 208		if (!bch2_extents_match(k, old)) {209			trace_move_extent_fail2(m, k, bkey_i_to_s_c(&new->k_i),210						NULL, "no match:");211			goto nowork;212		}213 214		bkey_reassemble(_insert.k, k);215		insert = _insert.k;216 217		bch2_bkey_buf_copy(&_new, c, bch2_keylist_front(keys));218		new = bkey_i_to_extent(_new.k);219		bch2_cut_front(iter.pos, &new->k_i);220 221		bch2_cut_front(iter.pos,	insert);222		bch2_cut_back(new->k.p,		insert);223		bch2_cut_back(insert->k.p,	&new->k_i);224 225		/*226		 * @old: extent that we read from227		 * @insert: key that we're going to update, initialized from228		 * extent currently in btree - same as @old unless we raced with229		 * other updates230		 * @new: extent with new pointers that we'll be adding to @insert231		 *232		 * Fist, drop rewrite_ptrs from @new:233		 */234		i = 0;235		bkey_for_each_ptr_decode(old.k, bch2_bkey_ptrs_c(old), p, entry_c) {236			if (((1U << i) & m->data_opts.rewrite_ptrs) &&237			    (ptr = bch2_extent_has_ptr(old, p, bkey_i_to_s(insert))) &&238			    !ptr->cached) {239				bch2_extent_ptr_set_cached(c, &m->op.opts,240							   bkey_i_to_s(insert), ptr);241				rewrites_found |= 1U << i;242			}243			i++;244		}245 246		if (m->data_opts.rewrite_ptrs &&247		    !rewrites_found &&248		    bch2_bkey_durability(c, k) >= m->op.opts.data_replicas) {249			trace_move_extent_fail2(m, k, bkey_i_to_s_c(&new->k_i), insert, "no rewrites found:");250			goto nowork;251		}252 253		/*254		 * A replica that we just wrote might conflict with a replica255		 * that we want to keep, due to racing with another move:256		 */257restart_drop_conflicting_replicas:258		extent_for_each_ptr(extent_i_to_s(new), ptr)259			if ((ptr_c = bch2_bkey_has_device_c(bkey_i_to_s_c(insert), ptr->dev)) &&260			    !ptr_c->cached) {261				bch2_bkey_drop_ptr_noerror(bkey_i_to_s(&new->k_i), ptr);262				goto restart_drop_conflicting_replicas;263			}264 265		if (!bkey_val_u64s(&new->k)) {266			trace_move_extent_fail2(m, k, bkey_i_to_s_c(&new->k_i), insert, "new replicas conflicted:");267			goto nowork;268		}269 270		/* Now, drop pointers that conflict with what we just wrote: */271		extent_for_each_ptr_decode(extent_i_to_s(new), p, entry)272			if ((ptr = bch2_bkey_has_device(bkey_i_to_s(insert), p.ptr.dev)))273				bch2_bkey_drop_ptr_noerror(bkey_i_to_s(insert), ptr);274 275		durability = bch2_bkey_durability(c, bkey_i_to_s_c(insert)) +276			bch2_bkey_durability(c, bkey_i_to_s_c(&new->k_i));277 278		/* Now, drop excess replicas: */279		rcu_read_lock();280restart_drop_extra_replicas:281		bkey_for_each_ptr_decode(old.k, bch2_bkey_ptrs(bkey_i_to_s(insert)), p, entry) {282			unsigned ptr_durability = bch2_extent_ptr_durability(c, &p);283 284			if (!p.ptr.cached &&285			    durability - ptr_durability >= m->op.opts.data_replicas) {286				durability -= ptr_durability;287 288				bch2_extent_ptr_set_cached(c, &m->op.opts,289							   bkey_i_to_s(insert), &entry->ptr);290				goto restart_drop_extra_replicas;291			}292		}293		rcu_read_unlock();294 295		/* Finally, add the pointers we just wrote: */296		extent_for_each_ptr_decode(extent_i_to_s(new), p, entry)297			bch2_extent_ptr_decoded_append(insert, &p);298 299		bch2_bkey_narrow_crcs(insert, (struct bch_extent_crc_unpacked) { 0 });300		bch2_extent_normalize_by_opts(c, &m->op.opts, bkey_i_to_s(insert));301 302		ret = bch2_sum_sector_overwrites(trans, &iter, insert,303						 &should_check_enospc,304						 &i_sectors_delta,305						 &disk_sectors_delta);306		if (ret)307			goto err;308 309		if (disk_sectors_delta > (s64) op->res.sectors) {310			ret = bch2_disk_reservation_add(c, &op->res,311						disk_sectors_delta - op->res.sectors,312						!should_check_enospc313						? BCH_DISK_RESERVATION_NOFAIL : 0);314			if (ret)315				goto out;316		}317 318		next_pos = insert->k.p;319 320		/*321		 * Check for nonce offset inconsistency:322		 * This is debug code - we've been seeing this bug rarely, and323		 * it's been hard to reproduce, so this should give us some more324		 * information when it does occur:325		 */326		int invalid = bch2_bkey_validate(c, bkey_i_to_s_c(insert), __btree_node_type(0, m->btree_id),327						 BCH_VALIDATE_commit);328		if (invalid) {329			struct printbuf buf = PRINTBUF;330 331			prt_str(&buf, "about to insert invalid key in data update path");332			prt_str(&buf, "\nold: ");333			bch2_bkey_val_to_text(&buf, c, old);334			prt_str(&buf, "\nk:   ");335			bch2_bkey_val_to_text(&buf, c, k);336			prt_str(&buf, "\nnew: ");337			bch2_bkey_val_to_text(&buf, c, bkey_i_to_s_c(insert));338 339			bch2_print_string_as_lines(KERN_ERR, buf.buf);340			printbuf_exit(&buf);341 342			bch2_fatal_error(c);343			ret = -EIO;344			goto out;345		}346 347		if (trace_data_update_enabled()) {348			struct printbuf buf = PRINTBUF;349 350			prt_str(&buf, "\nold: ");351			bch2_bkey_val_to_text(&buf, c, old);352			prt_str(&buf, "\nk:   ");353			bch2_bkey_val_to_text(&buf, c, k);354			prt_str(&buf, "\nnew: ");355			bch2_bkey_val_to_text(&buf, c, bkey_i_to_s_c(insert));356 357			trace_data_update(c, buf.buf);358			printbuf_exit(&buf);359		}360 361		ret =   bch2_insert_snapshot_whiteouts(trans, m->btree_id,362						k.k->p, bkey_start_pos(&insert->k)) ?:363			bch2_insert_snapshot_whiteouts(trans, m->btree_id,364						k.k->p, insert->k.p) ?:365			bch2_bkey_set_needs_rebalance(c, insert, &op->opts) ?:366			bch2_trans_update(trans, &iter, insert,367				BTREE_UPDATE_internal_snapshot_node) ?:368			bch2_trans_commit(trans, &op->res,369				NULL,370				BCH_TRANS_COMMIT_no_check_rw|371				BCH_TRANS_COMMIT_no_enospc|372				m->data_opts.btree_insert_flags);373		if (!ret) {374			bch2_btree_iter_set_pos(&iter, next_pos);375 376			this_cpu_add(c->counters[BCH_COUNTER_move_extent_finish], new->k.size);377			trace_move_extent_finish2(c, bkey_i_to_s_c(&new->k_i));378		}379err:380		if (bch2_err_matches(ret, BCH_ERR_transaction_restart))381			ret = 0;382		if (ret)383			break;384next:385		while (bkey_ge(iter.pos, bch2_keylist_front(keys)->k.p)) {386			bch2_keylist_pop_front(keys);387			if (bch2_keylist_empty(keys))388				goto out;389		}390		continue;391nowork:392		if (m->stats) {393			BUG_ON(k.k->p.offset <= iter.pos.offset);394			atomic64_inc(&m->stats->keys_raced);395			atomic64_add(k.k->p.offset - iter.pos.offset,396				     &m->stats->sectors_raced);397		}398 399		count_event(c, move_extent_fail);400 401		bch2_btree_iter_advance(&iter);402		goto next;403	}404out:405	bch2_trans_iter_exit(trans, &iter);406	bch2_bkey_buf_exit(&_insert, c);407	bch2_bkey_buf_exit(&_new, c);408	BUG_ON(bch2_err_matches(ret, BCH_ERR_transaction_restart));409	return ret;410}411 412int bch2_data_update_index_update(struct bch_write_op *op)413{414	return bch2_trans_run(op->c, __bch2_data_update_index_update(trans, op));415}416 417void bch2_data_update_read_done(struct data_update *m,418				struct bch_extent_crc_unpacked crc)419{420	/* write bio must own pages: */421	BUG_ON(!m->op.wbio.bio.bi_vcnt);422 423	m->op.crc = crc;424	m->op.wbio.bio.bi_iter.bi_size = crc.compressed_size << 9;425 426	closure_call(&m->op.cl, bch2_write, NULL, NULL);427}428 429void bch2_data_update_exit(struct data_update *update)430{431	struct bch_fs *c = update->op.c;432	struct bkey_s_c k = bkey_i_to_s_c(update->k.k);433 434	if (c->opts.nocow_enabled)435		bkey_nocow_unlock(c, k);436	bkey_put_dev_refs(c, k);437	bch2_bkey_buf_exit(&update->k, c);438	bch2_disk_reservation_put(c, &update->op.res);439	bch2_bio_free_pages_pool(c, &update->op.wbio.bio);440}441 442static void bch2_update_unwritten_extent(struct btree_trans *trans,443				  struct data_update *update)444{445	struct bch_fs *c = update->op.c;446	struct bio *bio = &update->op.wbio.bio;447	struct bkey_i_extent *e;448	struct write_point *wp;449	struct closure cl;450	struct btree_iter iter;451	struct bkey_s_c k;452	int ret;453 454	closure_init_stack(&cl);455	bch2_keylist_init(&update->op.insert_keys, update->op.inline_keys);456 457	while (bio_sectors(bio)) {458		unsigned sectors = bio_sectors(bio);459 460		bch2_trans_begin(trans);461 462		bch2_trans_iter_init(trans, &iter, update->btree_id, update->op.pos,463				     BTREE_ITER_slots);464		ret = lockrestart_do(trans, ({465			k = bch2_btree_iter_peek_slot(&iter);466			bkey_err(k);467		}));468		bch2_trans_iter_exit(trans, &iter);469 470		if (ret || !bch2_extents_match(k, bkey_i_to_s_c(update->k.k)))471			break;472 473		e = bkey_extent_init(update->op.insert_keys.top);474		e->k.p = update->op.pos;475 476		ret = bch2_alloc_sectors_start_trans(trans,477				update->op.target,478				false,479				update->op.write_point,480				&update->op.devs_have,481				update->op.nr_replicas,482				update->op.nr_replicas,483				update->op.watermark,484				0, &cl, &wp);485		if (bch2_err_matches(ret, BCH_ERR_operation_blocked)) {486			bch2_trans_unlock(trans);487			closure_sync(&cl);488			continue;489		}490 491		bch_err_fn_ratelimited(c, ret);492 493		if (ret)494			return;495 496		sectors = min(sectors, wp->sectors_free);497 498		bch2_key_resize(&e->k, sectors);499 500		bch2_open_bucket_get(c, wp, &update->op.open_buckets);501		bch2_alloc_sectors_append_ptrs(c, wp, &e->k_i, sectors, false);502		bch2_alloc_sectors_done(c, wp);503 504		bio_advance(bio, sectors << 9);505		update->op.pos.offset += sectors;506 507		extent_for_each_ptr(extent_i_to_s(e), ptr)508			ptr->unwritten = true;509		bch2_keylist_push(&update->op.insert_keys);510 511		ret = __bch2_data_update_index_update(trans, &update->op);512 513		bch2_open_buckets_put(c, &update->op.open_buckets);514 515		if (ret)516			break;517	}518 519	if (closure_nr_remaining(&cl) != 1) {520		bch2_trans_unlock(trans);521		closure_sync(&cl);522	}523}524 525void bch2_data_update_opts_to_text(struct printbuf *out, struct bch_fs *c,526				   struct bch_io_opts *io_opts,527				   struct data_update_opts *data_opts)528{529	printbuf_tabstop_push(out, 20);530	prt_str(out, "rewrite ptrs:\t");531	bch2_prt_u64_base2(out, data_opts->rewrite_ptrs);532	prt_newline(out);533 534	prt_str(out, "kill ptrs:\t");535	bch2_prt_u64_base2(out, data_opts->kill_ptrs);536	prt_newline(out);537 538	prt_str(out, "target:\t");539	bch2_target_to_text(out, c, data_opts->target);540	prt_newline(out);541 542	prt_str(out, "compression:\t");543	bch2_compression_opt_to_text(out, background_compression(*io_opts));544	prt_newline(out);545 546	prt_str(out, "opts.replicas:\t");547	prt_u64(out, io_opts->data_replicas);548 549	prt_str(out, "extra replicas:\t");550	prt_u64(out, data_opts->extra_replicas);551}552 553void bch2_data_update_to_text(struct printbuf *out, struct data_update *m)554{555	bch2_bkey_val_to_text(out, m->op.c, bkey_i_to_s_c(m->k.k));556	prt_newline(out);557	bch2_data_update_opts_to_text(out, m->op.c, &m->op.opts, &m->data_opts);558}559 560int bch2_extent_drop_ptrs(struct btree_trans *trans,561			  struct btree_iter *iter,562			  struct bkey_s_c k,563			  struct bch_io_opts *io_opts,564			  struct data_update_opts *data_opts)565{566	struct bch_fs *c = trans->c;567	struct bkey_i *n;568	int ret;569 570	n = bch2_bkey_make_mut_noupdate(trans, k);571	ret = PTR_ERR_OR_ZERO(n);572	if (ret)573		return ret;574 575	while (data_opts->kill_ptrs) {576		unsigned i = 0, drop = __fls(data_opts->kill_ptrs);577 578		bch2_bkey_drop_ptrs_noerror(bkey_i_to_s(n), ptr, i++ == drop);579		data_opts->kill_ptrs ^= 1U << drop;580	}581 582	/*583	 * If the new extent no longer has any pointers, bch2_extent_normalize()584	 * will do the appropriate thing with it (turning it into a585	 * KEY_TYPE_error key, or just a discard if it was a cached extent)586	 */587	bch2_extent_normalize_by_opts(c, io_opts, bkey_i_to_s(n));588 589	/*590	 * Since we're not inserting through an extent iterator591	 * (BTREE_ITER_all_snapshots iterators aren't extent iterators),592	 * we aren't using the extent overwrite path to delete, we're593	 * just using the normal key deletion path:594	 */595	if (bkey_deleted(&n->k) && !(iter->flags & BTREE_ITER_is_extents))596		n->k.size = 0;597 598	return bch2_trans_relock(trans) ?:599		bch2_trans_update(trans, iter, n, BTREE_UPDATE_internal_snapshot_node) ?:600		bch2_trans_commit(trans, NULL, NULL, BCH_TRANS_COMMIT_no_enospc);601}602 603int bch2_data_update_init(struct btree_trans *trans,604			  struct btree_iter *iter,605			  struct moving_context *ctxt,606			  struct data_update *m,607			  struct write_point_specifier wp,608			  struct bch_io_opts io_opts,609			  struct data_update_opts data_opts,610			  enum btree_id btree_id,611			  struct bkey_s_c k)612{613	struct bch_fs *c = trans->c;614	struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);615	const union bch_extent_entry *entry;616	struct extent_ptr_decoded p;617	unsigned i, reserve_sectors = k.k->size * data_opts.extra_replicas;618	int ret = 0;619 620	/*621	 * fs is corrupt  we have a key for a snapshot node that doesn't exist,622	 * and we have to check for this because we go rw before repairing the623	 * snapshots table - just skip it, we can move it later.624	 */625	if (unlikely(k.k->p.snapshot && !bch2_snapshot_equiv(c, k.k->p.snapshot)))626		return -BCH_ERR_data_update_done;627 628	if (!bkey_get_dev_refs(c, k))629		return -BCH_ERR_data_update_done;630 631	if (c->opts.nocow_enabled &&632	    !bkey_nocow_lock(c, ctxt, k)) {633		bkey_put_dev_refs(c, k);634		return -BCH_ERR_nocow_lock_blocked;635	}636 637	bch2_bkey_buf_init(&m->k);638	bch2_bkey_buf_reassemble(&m->k, c, k);639	m->btree_id	= btree_id;640	m->data_opts	= data_opts;641	m->ctxt		= ctxt;642	m->stats	= ctxt ? ctxt->stats : NULL;643 644	bch2_write_op_init(&m->op, c, io_opts);645	m->op.pos	= bkey_start_pos(k.k);646	m->op.version	= k.k->bversion;647	m->op.target	= data_opts.target;648	m->op.write_point = wp;649	m->op.nr_replicas = 0;650	m->op.flags	|= BCH_WRITE_PAGES_STABLE|651		BCH_WRITE_PAGES_OWNED|652		BCH_WRITE_DATA_ENCODED|653		BCH_WRITE_MOVE|654		m->data_opts.write_flags;655	m->op.compression_opt	= background_compression(io_opts);656	m->op.watermark		= m->data_opts.btree_insert_flags & BCH_WATERMARK_MASK;657 658	unsigned durability_have = 0, durability_removing = 0;659 660	i = 0;661	bkey_for_each_ptr_decode(k.k, ptrs, p, entry) {662		if (!p.ptr.cached) {663			rcu_read_lock();664			if (BIT(i) & m->data_opts.rewrite_ptrs) {665				if (crc_is_compressed(p.crc))666					reserve_sectors += k.k->size;667 668				m->op.nr_replicas += bch2_extent_ptr_desired_durability(c, &p);669				durability_removing += bch2_extent_ptr_desired_durability(c, &p);670			} else if (!(BIT(i) & m->data_opts.kill_ptrs)) {671				bch2_dev_list_add_dev(&m->op.devs_have, p.ptr.dev);672				durability_have += bch2_extent_ptr_durability(c, &p);673			}674			rcu_read_unlock();675		}676 677		/*678		 * op->csum_type is normally initialized from the fs/file's679		 * current options - but if an extent is encrypted, we require680		 * that it stays encrypted:681		 */682		if (bch2_csum_type_is_encryption(p.crc.csum_type)) {683			m->op.nonce	= p.crc.nonce + p.crc.offset;684			m->op.csum_type = p.crc.csum_type;685		}686 687		if (p.crc.compression_type == BCH_COMPRESSION_TYPE_incompressible)688			m->op.incompressible = true;689 690		i++;691	}692 693	unsigned durability_required = max(0, (int) (io_opts.data_replicas - durability_have));694 695	/*696	 * If current extent durability is less than io_opts.data_replicas,697	 * we're not trying to rereplicate the extent up to data_replicas here -698	 * unless extra_replicas was specified699	 *700	 * Increasing replication is an explicit operation triggered by701	 * rereplicate, currently, so that users don't get an unexpected -ENOSPC702	 */703	m->op.nr_replicas = min(durability_removing, durability_required) +704		m->data_opts.extra_replicas;705 706	/*707	 * If device(s) were set to durability=0 after data was written to them708	 * we can end up with a duribilty=0 extent, and the normal algorithm709	 * that tries not to increase durability doesn't work:710	 */711	if (!(durability_have + durability_removing))712		m->op.nr_replicas = max((unsigned) m->op.nr_replicas, 1);713 714	m->op.nr_replicas_required = m->op.nr_replicas;715 716	/*717	 * It might turn out that we don't need any new replicas, if the718	 * replicas or durability settings have been changed since the extent719	 * was written:720	 */721	if (!m->op.nr_replicas) {722		m->data_opts.kill_ptrs |= m->data_opts.rewrite_ptrs;723		m->data_opts.rewrite_ptrs = 0;724		/* if iter == NULL, it's just a promote */725		if (iter)726			ret = bch2_extent_drop_ptrs(trans, iter, k, &io_opts, &m->data_opts);727		goto out;728	}729 730	if (reserve_sectors) {731		ret = bch2_disk_reservation_add(c, &m->op.res, reserve_sectors,732				m->data_opts.extra_replicas733				? 0734				: BCH_DISK_RESERVATION_NOFAIL);735		if (ret)736			goto out;737	}738 739	if (bkey_extent_is_unwritten(k)) {740		bch2_update_unwritten_extent(trans, m);741		goto out;742	}743 744	return 0;745out:746	bch2_data_update_exit(m);747	return ret ?: -BCH_ERR_data_update_done;748}749 750void bch2_data_update_opts_normalize(struct bkey_s_c k, struct data_update_opts *opts)751{752	struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);753	unsigned i = 0;754 755	bkey_for_each_ptr(ptrs, ptr) {756		if ((opts->rewrite_ptrs & (1U << i)) && ptr->cached) {757			opts->kill_ptrs |= 1U << i;758			opts->rewrite_ptrs ^= 1U << i;759		}760 761		i++;762	}763}764