Update bcachefs sources to 15178a6479 bcachefs: Update btree ptrs after every writev0.14

19 files changed, 291 insertions, 249 deletions

diff --git a/.bcachefs_revision b/.bcachefs_revision
index 46d09322..85a9799a 100644
--- a/.bcachefs_revision
+++ b/.bcachefs_revision
@@ -1 +1 @@
-787de128a5caf209845e5a8d0f14f24e1a42492c
+15178a6479955d5aeaa124c0de9dabac87ffcca0
diff --git a/libbcachefs/bcachefs.h b/libbcachefs/bcachefs.h
index 125cf092..051aba63 100644
--- a/libbcachefs/bcachefs.h
+++ b/libbcachefs/bcachefs.h
@@ -675,7 +675,7 @@ struct bch_fs {
 	struct btree_key_cache	btree_key_cache;
 
 	struct workqueue_struct	*btree_update_wq;
-	struct workqueue_struct	*btree_error_wq;
+	struct workqueue_struct	*btree_io_complete_wq;
 	/* copygc needs its own workqueue for index updates.. */
 	struct workqueue_struct	*copygc_wq;
 
@@ -826,8 +826,6 @@ struct bch_fs {
 
 	atomic64_t		btree_writes_nr;
 	atomic64_t		btree_writes_sectors;
-	struct bio_list		btree_write_error_list;
-	struct work_struct	btree_write_error_work;
 	spinlock_t		btree_write_error_lock;
 
 	/* ERRORS */
diff --git a/libbcachefs/bcachefs_format.h b/libbcachefs/bcachefs_format.h
index 8a89ab0d..ee958f59 100644
--- a/libbcachefs/bcachefs_format.h
+++ b/libbcachefs/bcachefs_format.h
@@ -1210,7 +1210,8 @@ enum bcachefs_metadata_version {
 	bcachefs_metadata_version_inode_btree_change	= 11,
 	bcachefs_metadata_version_snapshot		= 12,
 	bcachefs_metadata_version_inode_backpointers	= 13,
-	bcachefs_metadata_version_max			= 14,
+	bcachefs_metadata_version_btree_ptr_sectors_written = 14,
+	bcachefs_metadata_version_max			= 15,
 };
 
 #define bcachefs_metadata_version_current	(bcachefs_metadata_version_max - 1)
diff --git a/libbcachefs/bkey_methods.c b/libbcachefs/bkey_methods.c
index 09e5dbf1..ff9d770a 100644
--- a/libbcachefs/bkey_methods.c
+++ b/libbcachefs/bkey_methods.c
@@ -101,6 +101,7 @@ const char *bch2_bkey_val_invalid(struct bch_fs *c, struct bkey_s_c k)
 static unsigned bch2_key_types_allowed[] = {
 	[BKEY_TYPE_extents] =
 		(1U << KEY_TYPE_error)|
+		(1U << KEY_TYPE_cookie)|
 		(1U << KEY_TYPE_extent)|
 		(1U << KEY_TYPE_reservation)|
 		(1U << KEY_TYPE_reflink_p)|
@@ -112,6 +113,7 @@ static unsigned bch2_key_types_allowed[] = {
 		(1U << KEY_TYPE_hash_whiteout)|
 		(1U << KEY_TYPE_dirent),
 	[BKEY_TYPE_xattrs] =
+		(1U << KEY_TYPE_cookie)|
 		(1U << KEY_TYPE_hash_whiteout)|
 		(1U << KEY_TYPE_xattr),
 	[BKEY_TYPE_alloc] =
diff --git a/libbcachefs/btree_cache.c b/libbcachefs/btree_cache.c
index 1aacd271..ed448276 100644
--- a/libbcachefs/btree_cache.c
+++ b/libbcachefs/btree_cache.c
@@ -712,26 +712,24 @@ static int lock_node_check_fn(struct six_lock *lock, void *p)
 
 static noinline void btree_bad_header(struct bch_fs *c, struct btree *b)
 {
-	char buf1[100], buf2[100], buf3[100], buf4[100];
+	char buf1[200], buf2[100], buf3[100];
 
 	if (!test_bit(BCH_FS_INITIAL_GC_DONE, &c->flags))
 		return;
 
-	bch2_bpos_to_text(&PBUF(buf1), b->key.k.type == KEY_TYPE_btree_ptr_v2
-		? bkey_i_to_btree_ptr_v2(&b->key)->v.min_key
-		: POS_MIN);
-	bch2_bpos_to_text(&PBUF(buf2), b->data->min_key);
+	bch2_bkey_val_to_text(&PBUF(buf1), c, bkey_i_to_s_c(&b->key));
+	bch2_bpos_to_text(&PBUF(buf3), b->data->max_key);
 
-	bch2_bpos_to_text(&PBUF(buf3), b->key.k.p);
-	bch2_bpos_to_text(&PBUF(buf4), b->data->max_key);
 	bch2_fs_inconsistent(c, "btree node header doesn't match ptr\n"
-			     "btree: ptr %u header %llu\n"
-			     "level: ptr %u header %llu\n"
-			     "min ptr %s node header %s\n"
-			     "max ptr %s node header %s",
-			     b->c.btree_id,	BTREE_NODE_ID(b->data),
-			     b->c.level,	BTREE_NODE_LEVEL(b->data),
-			     buf1, buf2, buf3, buf4);
+			     "btree %s level %u\n"
+			     "ptr: %s\n"
+			     "header: btree %s level %llu\n"
+			     "min %s max %s\n",
+			     bch2_btree_ids[b->c.btree_id], b->c.level,
+			     buf1,
+			     bch2_btree_ids[BTREE_NODE_ID(b->data)],
+			     BTREE_NODE_LEVEL(b->data),
+			     buf2, buf3);
 }
 
 static inline void btree_check_header(struct bch_fs *c, struct btree *b)
diff --git a/libbcachefs/btree_io.c b/libbcachefs/btree_io.c
index 957a6a9a..25f6a689 100644
--- a/libbcachefs/btree_io.c
+++ b/libbcachefs/btree_io.c
@@ -26,6 +26,7 @@ void bch2_btree_node_io_unlock(struct btree *b)
 {
 	EBUG_ON(!btree_node_write_in_flight(b));
 
+	clear_btree_node_write_in_flight_inner(b);
 	clear_btree_node_write_in_flight(b);
 	wake_up_bit(&b->flags, BTREE_NODE_write_in_flight);
 }
@@ -870,7 +871,8 @@ int bch2_btree_node_read_done(struct bch_fs *c, struct bch_dev *ca,
 	bool updated_range = b->key.k.type == KEY_TYPE_btree_ptr_v2 &&
 		BTREE_PTR_RANGE_UPDATED(&bkey_i_to_btree_ptr_v2(&b->key)->v);
 	unsigned u64s;
-	unsigned nonblacklisted_written = 0;
+	unsigned blacklisted_written, nonblacklisted_written = 0;
+	unsigned ptr_written = btree_ptr_sectors_written(&b->key);
 	int ret, retry_read = 0, write = READ;
 
 	b->version_ondisk = U16_MAX;
@@ -901,7 +903,7 @@ int bch2_btree_node_read_done(struct bch_fs *c, struct bch_dev *ca,
 			     b->data->keys.seq, bp->seq);
 	}
 
-	while (b->written < c->opts.btree_node_size) {
+	while (b->written < (ptr_written ?: c->opts.btree_node_size)) {
 		unsigned sectors, whiteout_u64s = 0;
 		struct nonce nonce;
 		struct bch_csum csum;
@@ -981,6 +983,10 @@ int bch2_btree_node_read_done(struct bch_fs *c, struct bch_dev *ca,
 		btree_err_on(blacklisted && first,
 			     BTREE_ERR_FIXABLE, c, ca, b, i,
 			     "first btree node bset has blacklisted journal seq");
+
+		btree_err_on(blacklisted && ptr_written,
+			     BTREE_ERR_FIXABLE, c, ca, b, i,
+			     "found blacklisted bset in btree node with sectors_written");
 		if (blacklisted && !first)
 			continue;
 
@@ -994,26 +1000,34 @@ int bch2_btree_node_read_done(struct bch_fs *c, struct bch_dev *ca,
 		nonblacklisted_written = b->written;
 	}
 
-	for (bne = write_block(b);
-	     bset_byte_offset(b, bne) < btree_bytes(c);
-	     bne = (void *) bne + block_bytes(c))
-		btree_err_on(bne->keys.seq == b->data->keys.seq &&
-			     !bch2_journal_seq_is_blacklisted(c,
-					le64_to_cpu(bne->keys.journal_seq),
-					true),
+	if (ptr_written) {
+		btree_err_on(b->written < ptr_written,
 			     BTREE_ERR_WANT_RETRY, c, ca, b, NULL,
-			     "found bset signature after last bset");
+			     "btree node data missing: expected %u sectors, found %u",
+			     ptr_written, b->written);
+	} else {
+		for (bne = write_block(b);
+		     bset_byte_offset(b, bne) < btree_bytes(c);
+		     bne = (void *) bne + block_bytes(c))
+			btree_err_on(bne->keys.seq == b->data->keys.seq &&
+				     !bch2_journal_seq_is_blacklisted(c,
+								      le64_to_cpu(bne->keys.journal_seq),
+								      true),
+				     BTREE_ERR_WANT_RETRY, c, ca, b, NULL,
+				     "found bset signature after last bset");
 
-	/*
-	 * Blacklisted bsets are those that were written after the most recent
-	 * (flush) journal write. Since there wasn't a flush, they may not have
-	 * made it to all devices - which means we shouldn't write new bsets
-	 * after them, as that could leave a gap and then reads from that device
-	 * wouldn't find all the bsets in that btree node - which means it's
-	 * important that we start writing new bsets after the most recent _non_
-	 * blacklisted bset:
-	 */
-	b->written = nonblacklisted_written;
+		/*
+		 * Blacklisted bsets are those that were written after the most recent
+		 * (flush) journal write. Since there wasn't a flush, they may not have
+		 * made it to all devices - which means we shouldn't write new bsets
+		 * after them, as that could leave a gap and then reads from that device
+		 * wouldn't find all the bsets in that btree node - which means it's
+		 * important that we start writing new bsets after the most recent _non_
+		 * blacklisted bset:
+		 */
+		blacklisted_written = b->written;
+		b->written = nonblacklisted_written;
+	}
 
 	sorted = btree_bounce_alloc(c, btree_bytes(c), &used_mempool);
 	sorted->keys.u64s = 0;
@@ -1081,6 +1095,9 @@ int bch2_btree_node_read_done(struct bch_fs *c, struct bch_dev *ca,
 		if (ca->mi.state != BCH_MEMBER_STATE_rw)
 			set_btree_node_need_rewrite(b);
 	}
+
+	if (!ptr_written)
+		set_btree_node_need_rewrite(b);
 out:
 	mempool_free(iter, &c->fill_iter);
 	return retry_read;
@@ -1578,6 +1595,7 @@ static void btree_node_write_done(struct bch_fs *c, struct btree *b)
 			goto do_write;
 
 		new &= ~(1U << BTREE_NODE_write_in_flight);
+		new &= ~(1U << BTREE_NODE_write_in_flight_inner);
 	} while ((v = cmpxchg(&b->flags, old, new)) != old);
 
 	wake_up_bit(&b->flags, BTREE_NODE_write_in_flight);
@@ -1596,10 +1614,12 @@ do_write:
 			new &= ~(1U << BTREE_NODE_dirty);
 			new &= ~(1U << BTREE_NODE_need_write);
 			new |=  (1U << BTREE_NODE_write_in_flight);
+			new |=  (1U << BTREE_NODE_write_in_flight_inner);
 			new |=  (1U << BTREE_NODE_just_written);
 			new ^=  (1U << BTREE_NODE_write_idx);
 		} else {
 			new &= ~(1U << BTREE_NODE_write_in_flight);
+			new &= ~(1U << BTREE_NODE_write_in_flight_inner);
 		}
 	} while ((v = cmpxchg(&b->flags, old, new)) != old);
 
@@ -1609,52 +1629,38 @@ do_write:
 	six_unlock_read(&b->c.lock);
 }
 
-static void bch2_btree_node_write_error(struct bch_fs *c,
-					struct btree_write_bio *wbio)
+static void btree_node_write_work(struct work_struct *work)
 {
+	struct btree_write_bio *wbio =
+		container_of(work, struct btree_write_bio, work);
+	struct bch_fs *c	= wbio->wbio.c;
 	struct btree *b		= wbio->wbio.bio.bi_private;
-	struct bkey_buf k;
 	struct bch_extent_ptr *ptr;
-	struct btree_trans trans;
-	struct btree_iter *iter;
 	int ret;
 
-	bch2_bkey_buf_init(&k);
-	bch2_trans_init(&trans, c, 0, 0);
-
-	iter = bch2_trans_get_node_iter(&trans, b->c.btree_id, b->key.k.p,
-					BTREE_MAX_DEPTH, b->c.level, 0);
-retry:
-	ret = bch2_btree_iter_traverse(iter);
-	if (ret)
-		goto err;
-
-	/* has node been freed? */
-	if (iter->l[b->c.level].b != b) {
-		/* node has been freed: */
-		BUG_ON(!btree_node_dying(b));
-		goto out;
-	}
-
-	BUG_ON(!btree_node_hashed(b));
-
-	bch2_bkey_buf_copy(&k, c, &b->key);
+	btree_bounce_free(c,
+		wbio->data_bytes,
+		wbio->wbio.used_mempool,
+		wbio->data);
 
-	bch2_bkey_drop_ptrs(bkey_i_to_s(k.k), ptr,
+	bch2_bkey_drop_ptrs(bkey_i_to_s(&wbio->key), ptr,
 		bch2_dev_list_has_dev(wbio->wbio.failed, ptr->dev));
 
-	if (!bch2_bkey_nr_ptrs(bkey_i_to_s_c(k.k)))
+	if (!bch2_bkey_nr_ptrs(bkey_i_to_s_c(&wbio->key)))
 		goto err;
 
-	ret = bch2_btree_node_update_key(&trans, iter, b, k.k);
-	if (ret == -EINTR)
-		goto retry;
-	if (ret)
-		goto err;
+	if (wbio->wbio.first_btree_write) {
+		if (wbio->wbio.failed.nr) {
+
+		}
+	} else {
+		ret = bch2_trans_do(c, NULL, NULL, 0,
+			bch2_btree_node_update_key_get_iter(&trans, b, &wbio->key,
+							    !wbio->wbio.failed.nr));
+		if (ret)
+			goto err;
+	}
 out:
-	bch2_trans_iter_put(&trans, iter);
-	bch2_trans_exit(&trans);
-	bch2_bkey_buf_exit(&k, c);
 	bio_put(&wbio->wbio.bio);
 	btree_node_write_done(c, b);
 	return;
@@ -1664,58 +1670,14 @@ err:
 	goto out;
 }
 
-void bch2_btree_write_error_work(struct work_struct *work)
-{
-	struct bch_fs *c = container_of(work, struct bch_fs,
-					btree_write_error_work);
-	struct bio *bio;
-
-	while (1) {
-		spin_lock_irq(&c->btree_write_error_lock);
-		bio = bio_list_pop(&c->btree_write_error_list);
-		spin_unlock_irq(&c->btree_write_error_lock);
-
-		if (!bio)
-			break;
-
-		bch2_btree_node_write_error(c,
-			container_of(bio, struct btree_write_bio, wbio.bio));
-	}
-}
-
-static void btree_node_write_work(struct work_struct *work)
-{
-	struct btree_write_bio *wbio =
-		container_of(work, struct btree_write_bio, work);
-	struct bch_fs *c	= wbio->wbio.c;
-	struct btree *b		= wbio->wbio.bio.bi_private;
-
-	btree_bounce_free(c,
-		wbio->bytes,
-		wbio->wbio.used_mempool,
-		wbio->data);
-
-	if (wbio->wbio.failed.nr) {
-		unsigned long flags;
-
-		spin_lock_irqsave(&c->btree_write_error_lock, flags);
-		bio_list_add(&c->btree_write_error_list, &wbio->wbio.bio);
-		spin_unlock_irqrestore(&c->btree_write_error_lock, flags);
-
-		queue_work(c->btree_error_wq, &c->btree_write_error_work);
-		return;
-	}
-
-	bio_put(&wbio->wbio.bio);
-	btree_node_write_done(c, b);
-}
-
 static void btree_node_write_endio(struct bio *bio)
 {
 	struct bch_write_bio *wbio	= to_wbio(bio);
 	struct bch_write_bio *parent	= wbio->split ? wbio->parent : NULL;
 	struct bch_write_bio *orig	= parent ?: wbio;
+	struct btree_write_bio *wb	= container_of(orig, struct btree_write_bio, wbio);
 	struct bch_fs *c		= wbio->c;
+	struct btree *b			= wbio->bio.bi_private;
 	struct bch_dev *ca		= bch_dev_bkey_exists(c, wbio->dev);
 	unsigned long flags;
 
@@ -1736,13 +1698,13 @@ static void btree_node_write_endio(struct bio *bio)
 	if (parent) {
 		bio_put(bio);
 		bio_endio(&parent->bio);
-	} else {
-		struct btree_write_bio *wb =
-			container_of(orig, struct btree_write_bio, wbio);
-
-		INIT_WORK(&wb->work, btree_node_write_work);
-		queue_work(c->io_complete_wq, &wb->work);
+		return;
 	}
+
+	clear_btree_node_write_in_flight_inner(b);
+	wake_up_bit(&b->flags, BTREE_NODE_write_in_flight_inner);
+	INIT_WORK(&wb->work, btree_node_write_work);
+	queue_work(c->btree_io_complete_wq, &wb->work);
 }
 
 static int validate_bset_for_write(struct bch_fs *c, struct btree *b,
@@ -1767,8 +1729,15 @@ static int validate_bset_for_write(struct bch_fs *c, struct btree *b,
 static void btree_write_submit(struct work_struct *work)
 {
 	struct btree_write_bio *wbio = container_of(work, struct btree_write_bio, work);
+	struct bch_extent_ptr *ptr;
+	__BKEY_PADDED(k, BKEY_BTREE_PTR_VAL_U64s_MAX) tmp;
+
+	bkey_copy(&tmp.k, &wbio->key);
+
+	bkey_for_each_ptr(bch2_bkey_ptrs(bkey_i_to_s(&tmp.k)), ptr)
+		ptr->offset += wbio->sector_offset;
 
-	bch2_submit_wbio_replicas(&wbio->wbio, wbio->wbio.c, BCH_DATA_btree, &wbio->key);
+	bch2_submit_wbio_replicas(&wbio->wbio, wbio->wbio.c, BCH_DATA_btree, &tmp.k);
 }
 
 void __bch2_btree_node_write(struct bch_fs *c, struct btree *b, bool already_started)
@@ -1778,7 +1747,6 @@ void __bch2_btree_node_write(struct bch_fs *c, struct btree *b, bool already_sta
 	struct bset *i;
 	struct btree_node *bn = NULL;
 	struct btree_node_entry *bne = NULL;
-	struct bch_extent_ptr *ptr;
 	struct sort_iter sort_iter;
 	struct nonce nonce;
 	unsigned bytes_to_write, sectors_to_write, bytes, u64s;
@@ -1818,6 +1786,7 @@ void __bch2_btree_node_write(struct bch_fs *c, struct btree *b, bool already_sta
 		new &= ~(1 << BTREE_NODE_dirty);
 		new &= ~(1 << BTREE_NODE_need_write);
 		new |=  (1 << BTREE_NODE_write_in_flight);
+		new |=  (1 << BTREE_NODE_write_in_flight_inner);
 		new |=  (1 << BTREE_NODE_just_written);
 		new ^=  (1 << BTREE_NODE_write_idx);
 	} while (cmpxchg_acquire(&b->flags, old, new) != old);
@@ -1969,37 +1938,30 @@ do_write:
 			    struct btree_write_bio, wbio.bio);
 	wbio_init(&wbio->wbio.bio);
 	wbio->data			= data;
-	wbio->bytes			= bytes;
+	wbio->data_bytes		= bytes;
+	wbio->sector_offset		= b->written;
 	wbio->wbio.c			= c;
 	wbio->wbio.used_mempool		= used_mempool;
+	wbio->wbio.first_btree_write	= !b->written;
 	wbio->wbio.bio.bi_opf		= REQ_OP_WRITE|REQ_META;
 	wbio->wbio.bio.bi_end_io	= btree_node_write_endio;
 	wbio->wbio.bio.bi_private	= b;
 
 	bch2_bio_map(&wbio->wbio.bio, data, sectors_to_write << 9);
 
-	/*
-	 * If we're appending to a leaf node, we don't technically need FUA -
-	 * this write just needs to be persisted before the next journal write,
-	 * which will be marked FLUSH|FUA.
-	 *
-	 * Similarly if we're writing a new btree root - the pointer is going to
-	 * be in the next journal entry.
-	 *
-	 * But if we're writing a new btree node (that isn't a root) or
-	 * appending to a non leaf btree node, we need either FUA or a flush
-	 * when we write the parent with the new pointer. FUA is cheaper than a
-	 * flush, and writes appending to leaf nodes aren't blocking anything so
-	 * just make all btree node writes FUA to keep things sane.
-	 */
-
 	bkey_copy(&wbio->key, &b->key);
 
-	bkey_for_each_ptr(bch2_bkey_ptrs(bkey_i_to_s(&wbio->key)), ptr)
-		ptr->offset += b->written;
-
 	b->written += sectors_to_write;
 
+	if (wbio->wbio.first_btree_write &&
+	    b->key.k.type == KEY_TYPE_btree_ptr_v2)
+		bkey_i_to_btree_ptr_v2(&b->key)->v.sectors_written =
+			cpu_to_le16(b->written);
+
+	if (wbio->key.k.type == KEY_TYPE_btree_ptr_v2)
+		bkey_i_to_btree_ptr_v2(&wbio->key)->v.sectors_written =
+			cpu_to_le16(b->written);
+
 	atomic64_inc(&c->btree_writes_nr);
 	atomic64_add(sectors_to_write, &c->btree_writes_sectors);
 
@@ -2008,6 +1970,10 @@ do_write:
 	return;
 err:
 	set_btree_node_noevict(b);
+	if (!b->written &&
+	    b->key.k.type == KEY_TYPE_btree_ptr_v2)
+		bkey_i_to_btree_ptr_v2(&b->key)->v.sectors_written =
+			cpu_to_le16(sectors_to_write);
 	b->written += sectors_to_write;
 nowrite:
 	btree_bounce_free(c, bytes, used_mempool, data);
diff --git a/libbcachefs/btree_io.h b/libbcachefs/btree_io.h
index 3732d135..7fdcf879 100644
--- a/libbcachefs/btree_io.h
+++ b/libbcachefs/btree_io.h
@@ -32,6 +32,13 @@ static inline void clear_btree_node_dirty(struct bch_fs *c, struct btree *b)
 		atomic_dec(&c->btree_cache.dirty);
 }
 
+static inline unsigned btree_ptr_sectors_written(struct bkey_i *k)
+{
+	return k->k.type == KEY_TYPE_btree_ptr_v2
+		? le16_to_cpu(bkey_i_to_btree_ptr_v2(k)->v.sectors_written)
+		: 0;
+}
+
 struct btree_read_bio {
 	struct bch_fs		*c;
 	struct btree		*b;
@@ -48,7 +55,8 @@ struct btree_write_bio {
 	struct work_struct	work;
 	__BKEY_PADDED(key, BKEY_BTREE_PTR_VAL_U64s_MAX);
 	void			*data;
-	unsigned		bytes;
+	unsigned		data_bytes;
+	unsigned		sector_offset;
 	struct bch_write_bio	wbio;
 };
 
@@ -137,7 +145,6 @@ int bch2_btree_root_read(struct bch_fs *, enum btree_id,
 
 void bch2_btree_complete_write(struct bch_fs *, struct btree *,
 			      struct btree_write *);
-void bch2_btree_write_error_work(struct work_struct *);
 
 void __bch2_btree_node_write(struct bch_fs *, struct btree *, bool);
 bool bch2_btree_post_write_cleanup(struct bch_fs *, struct btree *);
diff --git a/libbcachefs/btree_iter.c b/libbcachefs/btree_iter.c
index 24d7422c..c7473981 100644
--- a/libbcachefs/btree_iter.c
+++ b/libbcachefs/btree_iter.c
@@ -347,7 +347,6 @@ bool __bch2_btree_node_lock(struct btree *b, struct bpos pos,
 #ifdef CONFIG_BCACHEFS_DEBUG
 static void bch2_btree_iter_verify_locks(struct btree_iter *iter)
 {
-	struct bch_fs *c = iter->trans->c;
 	unsigned l;
 
 	if (!(iter->trans->iters_linked & (1ULL << iter->idx))) {
@@ -623,7 +622,7 @@ static void bch2_btree_iter_verify(struct btree_iter *iter)
 	       (iter->flags & BTREE_ITER_ALL_SNAPSHOTS) &&
 	       !btree_type_has_snapshots(iter->btree_id));
 
-	for (i = 0; i < BTREE_MAX_DEPTH; i++) {
+	for (i = 0; i < (type != BTREE_ITER_CACHED ? BTREE_MAX_DEPTH : 1); i++) {
 		if (!iter->l[i].b) {
 			BUG_ON(c->btree_roots[iter->btree_id].b->c.level > i);
 			break;
@@ -1618,7 +1617,9 @@ inline bool bch2_btree_iter_advance(struct btree_iter *iter)
 inline bool bch2_btree_iter_rewind(struct btree_iter *iter)
 {
 	struct bpos pos = bkey_start_pos(&iter->k);
-	bool ret = bpos_cmp(pos, POS_MIN) != 0;
+	bool ret = (iter->flags & BTREE_ITER_ALL_SNAPSHOTS
+		    ? bpos_cmp(pos, POS_MIN)
+		    : bkey_cmp(pos, POS_MIN)) != 0;
 
 	if (ret && !(iter->flags & BTREE_ITER_IS_EXTENTS))
 		pos = bkey_predecessor(iter, pos);
diff --git a/libbcachefs/btree_iter.h b/libbcachefs/btree_iter.h
index 58f15b71..7385cca4 100644
--- a/libbcachefs/btree_iter.h
+++ b/libbcachefs/btree_iter.h
@@ -132,7 +132,7 @@ void __bch2_btree_iter_downgrade(struct btree_iter *, unsigned);
 
 static inline void bch2_btree_iter_downgrade(struct btree_iter *iter)
 {
-	unsigned new_locks_want = (iter->flags & BTREE_ITER_INTENT ? 1 : 0);
+	unsigned new_locks_want = iter->level + !!(iter->flags & BTREE_ITER_INTENT);
 
 	if (iter->locks_want > new_locks_want)
 		__bch2_btree_iter_downgrade(iter, new_locks_want);
diff --git a/libbcachefs/btree_types.h b/libbcachefs/btree_types.h
index a2581500..07c9ba4e 100644
--- a/libbcachefs/btree_types.h
+++ b/libbcachefs/btree_types.h
@@ -435,6 +435,7 @@ enum btree_flags {
 	BTREE_NODE_write_idx,
 	BTREE_NODE_accessed,
 	BTREE_NODE_write_in_flight,
+	BTREE_NODE_write_in_flight_inner,
 	BTREE_NODE_just_written,
 	BTREE_NODE_dying,
 	BTREE_NODE_fake,
@@ -449,6 +450,7 @@ BTREE_FLAG(noevict);
 BTREE_FLAG(write_idx);
 BTREE_FLAG(accessed);
 BTREE_FLAG(write_in_flight);
+BTREE_FLAG(write_in_flight_inner);
 BTREE_FLAG(just_written);
 BTREE_FLAG(dying);
 BTREE_FLAG(fake);
diff --git a/libbcachefs/btree_update.h b/libbcachefs/btree_update.h
index 12065bba..bab135fa 100644
--- a/libbcachefs/btree_update.h
+++ b/libbcachefs/btree_update.h
@@ -74,7 +74,9 @@ int bch2_btree_node_rewrite(struct btree_trans *, struct btree_iter *,
 			    __le64, unsigned);
 void bch2_btree_node_rewrite_async(struct bch_fs *, struct btree *);
 int bch2_btree_node_update_key(struct btree_trans *, struct btree_iter *,
-			       struct btree *, struct bkey_i *);
+			       struct btree *, struct bkey_i *, bool);
+int bch2_btree_node_update_key_get_iter(struct btree_trans *,
+				struct btree *, struct bkey_i *, bool);
 
 int bch2_trans_update(struct btree_trans *, struct btree_iter *,
 		      struct bkey_i *, enum btree_update_flags);
diff --git a/libbcachefs/btree_update_interior.c b/libbcachefs/btree_update_interior.c
index 0b4e4056..a2542408 100644
--- a/libbcachefs/btree_update_interior.c
+++ b/libbcachefs/btree_update_interior.c
@@ -246,11 +246,7 @@ retry:
 		goto retry;
 	}
 
-	if (c->sb.features & (1ULL << BCH_FEATURE_btree_ptr_v2))
-		bkey_btree_ptr_v2_init(&tmp.k);
-	else
-		bkey_btree_ptr_init(&tmp.k);
-
+	bkey_btree_ptr_v2_init(&tmp.k);
 	bch2_alloc_sectors_append_ptrs(c, wp, &tmp.k, c->opts.btree_node_size);
 
 	bch2_open_bucket_get(c, wp, &ob);
@@ -567,7 +563,8 @@ static void btree_update_nodes_written(struct btree_update *as)
 		six_unlock_read(&old->c.lock);
 
 		if (seq == as->old_nodes_seq[i])
-			bch2_btree_node_wait_on_write(old);
+			wait_on_bit_io(&old->flags, BTREE_NODE_write_in_flight_inner,
+				       TASK_UNINTERRUPTIBLE);
 	}
 
 	/*
@@ -1153,6 +1150,9 @@ static void bch2_insert_fixup_btree_ptr(struct btree_update *as, struct btree *b
 	struct bkey_packed *k;
 	const char *invalid;
 
+	BUG_ON(insert->k.type == KEY_TYPE_btree_ptr_v2 &&
+	       !btree_ptr_sectors_written(insert));
+
 	invalid = bch2_bkey_invalid(c, bkey_i_to_s_c(insert), btree_node_type(b)) ?:
 		bch2_bkey_in_btree_node(b, bkey_i_to_s_c(insert));
 	if (invalid) {
@@ -1395,6 +1395,7 @@ static void btree_split(struct btree_update *as,
 		six_unlock_write(&n2->c.lock);
 		six_unlock_write(&n1->c.lock);
 
+		bch2_btree_node_write(c, n1, SIX_LOCK_intent);
 		bch2_btree_node_write(c, n2, SIX_LOCK_intent);
 
 		/*
@@ -1422,12 +1423,12 @@ static void btree_split(struct btree_update *as,
 		bch2_btree_build_aux_trees(n1);
 		six_unlock_write(&n1->c.lock);
 
+		bch2_btree_node_write(c, n1, SIX_LOCK_intent);
+
 		if (parent)
 			bch2_keylist_add(&as->parent_keys, &n1->key);
 	}
 
-	bch2_btree_node_write(c, n1, SIX_LOCK_intent);
-
 	/* New nodes all written, now make them visible: */
 
 	if (parent) {
@@ -1703,13 +1704,13 @@ retry:
 	bch2_btree_build_aux_trees(n);
 	six_unlock_write(&n->c.lock);
 
+	bch2_btree_node_write(c, n, SIX_LOCK_intent);
+
 	bkey_init(&delete.k);
 	delete.k.p = prev->key.k.p;
 	bch2_keylist_add(&as->parent_keys, &delete);
 	bch2_keylist_add(&as->parent_keys, &n->key);
 
-	bch2_btree_node_write(c, n, SIX_LOCK_intent);
-
 	bch2_btree_insert_node(as, trans, iter, parent, &as->parent_keys, flags);
 
 	bch2_btree_update_get_open_buckets(as, n);
@@ -1883,74 +1884,109 @@ void bch2_btree_node_rewrite_async(struct bch_fs *c, struct btree *b)
 	queue_work(c->btree_interior_update_worker, &a->work);
 }
 
-static void __bch2_btree_node_update_key(struct btree_update *as,
-					 struct btree_trans *trans,
-					 struct btree_iter *iter,
-					 struct btree *b, struct btree *new_hash,
-					 struct bkey_i *new_key)
+static int __bch2_btree_node_update_key(struct btree_trans *trans,
+					struct btree_iter *iter,
+					struct btree *b, struct btree *new_hash,
+					struct bkey_i *new_key,
+					bool skip_triggers)
 {
-	struct bch_fs *c = as->c;
+	struct bch_fs *c = trans->c;
+	struct btree_iter *iter2 = NULL;
 	struct btree *parent;
+	u64 journal_entries[BKEY_BTREE_PTR_U64s_MAX];
 	int ret;
 
-	btree_update_will_delete_key(as, &b->key);
-	btree_update_will_add_key(as, new_key);
+	if (!skip_triggers) {
+		ret = bch2_trans_mark_key(trans,
+					  bkey_s_c_null,
+					  bkey_i_to_s_c(new_key),
+					  BTREE_TRIGGER_INSERT);
+		if (ret)
+			return ret;
+
+		ret = bch2_trans_mark_key(trans,
+					  bkey_i_to_s_c(&b->key),
+					  bkey_s_c_null,
+					  BTREE_TRIGGER_OVERWRITE);
+		if (ret)
+			return ret;
+	}
+
+	if (new_hash) {
+		bkey_copy(&new_hash->key, new_key);
+		ret = bch2_btree_node_hash_insert(&c->btree_cache,
+				new_hash, b->c.level, b->c.btree_id);
+		BUG_ON(ret);
+	}
 
 	parent = btree_node_parent(iter, b);
 	if (parent) {
-		if (new_hash) {
-			bkey_copy(&new_hash->key, new_key);
-			ret = bch2_btree_node_hash_insert(&c->btree_cache,
-					new_hash, b->c.level, b->c.btree_id);
-			BUG_ON(ret);
-		}
+		iter2 = bch2_trans_copy_iter(trans, iter);
 
-		bch2_keylist_add(&as->parent_keys, new_key);
-		bch2_btree_insert_node(as, trans, iter, parent, &as->parent_keys, 0);
+		BUG_ON(iter2->level != b->c.level);
+		BUG_ON(bpos_cmp(iter2->pos, new_key->k.p));
 
-		if (new_hash) {
-			mutex_lock(&c->btree_cache.lock);
-			bch2_btree_node_hash_remove(&c->btree_cache, new_hash);
+		btree_node_unlock(iter2, iter2->level);
+		iter2->l[iter2->level].b = BTREE_ITER_NO_NODE_UP;
+		iter2->level++;
 
-			bch2_btree_node_hash_remove(&c->btree_cache, b);
-
-			bkey_copy(&b->key, new_key);
-			ret = __bch2_btree_node_hash_insert(&c->btree_cache, b);
-			BUG_ON(ret);
-			mutex_unlock(&c->btree_cache.lock);
-		} else {
-			bkey_copy(&b->key, new_key);
-		}
+		ret   = bch2_btree_iter_traverse(iter2) ?:
+			bch2_trans_update(trans, iter2, new_key, BTREE_TRIGGER_NORUN);
+		if (ret)
+			goto err;
 	} else {
 		BUG_ON(btree_node_root(c, b) != b);
 
-		bch2_btree_node_lock_write(b, iter);
-		bkey_copy(&b->key, new_key);
+		trans->extra_journal_entries = (void *) &journal_entries[0];
+		trans->extra_journal_entry_u64s =
+			journal_entry_set((void *) &journal_entries[0],
+					  BCH_JSET_ENTRY_btree_root,
+					  b->c.btree_id, b->c.level,
+					  new_key, new_key->k.u64s);
+	}
 
-		if (btree_ptr_hash_val(&b->key) != b->hash_val) {
-			mutex_lock(&c->btree_cache.lock);
-			bch2_btree_node_hash_remove(&c->btree_cache, b);
+	ret = bch2_trans_commit(trans, NULL, NULL,
+				BTREE_INSERT_NOFAIL|
+				BTREE_INSERT_NOCHECK_RW|
+				BTREE_INSERT_JOURNAL_RECLAIM|
+				BTREE_INSERT_JOURNAL_RESERVED|
+				BTREE_INSERT_NOUNLOCK);
+	if (ret)
+		goto err;
 
-			ret = __bch2_btree_node_hash_insert(&c->btree_cache, b);
-			BUG_ON(ret);
-			mutex_unlock(&c->btree_cache.lock);
-		}
+	bch2_btree_node_lock_write(b, iter);
 
-		btree_update_updated_root(as, b);
-		bch2_btree_node_unlock_write(b, iter);
+	if (new_hash) {
+		mutex_lock(&c->btree_cache.lock);
+		bch2_btree_node_hash_remove(&c->btree_cache, new_hash);
+		bch2_btree_node_hash_remove(&c->btree_cache, b);
+
+		bkey_copy(&b->key, new_key);
+		ret = __bch2_btree_node_hash_insert(&c->btree_cache, b);
+		BUG_ON(ret);
+		mutex_unlock(&c->btree_cache.lock);
+	} else {
+		bkey_copy(&b->key, new_key);
 	}
 
-	bch2_btree_update_done(as);
+	bch2_btree_node_unlock_write(b, iter);
+out:
+	bch2_trans_iter_put(trans, iter2);
+	return ret;
+err:
+	if (new_hash) {
+		mutex_lock(&c->btree_cache.lock);
+		bch2_btree_node_hash_remove(&c->btree_cache, b);
+		mutex_unlock(&c->btree_cache.lock);
+	}
+	goto out;
 }
 
-int bch2_btree_node_update_key(struct btree_trans *trans,
-			       struct btree_iter *iter,
-			       struct btree *b,
-			       struct bkey_i *new_key)
+int bch2_btree_node_update_key(struct btree_trans *trans, struct btree_iter *iter,
+			       struct btree *b, struct bkey_i *new_key,
+			       bool skip_triggers)
 {
 	struct bch_fs *c = trans->c;
-	struct btree *parent = btree_node_parent(iter, b);
-	struct btree_update *as = NULL;
 	struct btree *new_hash = NULL;
 	struct closure cl;
 	int ret = 0;
@@ -1964,27 +2000,18 @@ int bch2_btree_node_update_key(struct btree_trans *trans,
 	if (btree_ptr_hash_val(new_key) != b->hash_val) {
 		ret = bch2_btree_cache_cannibalize_lock(c, &cl);
 		if (ret) {
-			bch2_trans_unlock(iter->trans);
+			bch2_trans_unlock(trans);
 			closure_sync(&cl);
-			if (!bch2_trans_relock(iter->trans))
+			if (!bch2_trans_relock(trans))
 				return -EINTR;
 		}
 
 		new_hash = bch2_btree_node_mem_alloc(c);
 	}
 
-	as = bch2_btree_update_start(iter, b->c.level,
-		parent ? btree_update_reserve_required(c, parent) : 0,
-		BTREE_INSERT_NOFAIL);
-	if (IS_ERR(as)) {
-		ret = PTR_ERR(as);
-		goto err;
-	}
-
-	__bch2_btree_node_update_key(as, trans, iter, b, new_hash, new_key);
+	ret = __bch2_btree_node_update_key(trans, iter, b, new_hash,
+					   new_key, skip_triggers);
 
-	bch2_btree_iter_downgrade(iter);
-err:
 	if (new_hash) {
 		mutex_lock(&c->btree_cache.lock);
 		list_move(&new_hash->list, &c->btree_cache.freeable);
@@ -1998,6 +2025,35 @@ err:
 	return ret;
 }
 
+int bch2_btree_node_update_key_get_iter(struct btree_trans *trans,
+					struct btree *b, struct bkey_i *new_key,
+					bool skip_triggers)
+{
+	struct btree_iter *iter;
+	int ret;
+
+	iter = bch2_trans_get_node_iter(trans, b->c.btree_id, b->key.k.p,
+					BTREE_MAX_DEPTH, b->c.level,
+					BTREE_ITER_INTENT);
+	ret = bch2_btree_iter_traverse(iter);
+	if (ret)
+		goto out;
+
+	/* has node been freed? */
+	if (iter->l[b->c.level].b != b) {
+		/* node has been freed: */
+		BUG_ON(!btree_node_dying(b));
+		goto out;
+	}
+
+	BUG_ON(!btree_node_hashed(b));
+
+	ret = bch2_btree_node_update_key(trans, iter, b, new_key, skip_triggers);
+out:
+	bch2_trans_iter_put(trans, iter);
+	return ret;
+}
+
 /* Init code: */
 
 /*
diff --git a/libbcachefs/btree_update_leaf.c b/libbcachefs/btree_update_leaf.c
index 0843e2c3..d319e27a 100644
--- a/libbcachefs/btree_update_leaf.c
+++ b/libbcachefs/btree_update_leaf.c
@@ -890,7 +890,8 @@ int __bch2_trans_commit(struct btree_trans *trans)
 	unsigned u64s, reset_flags = 0;
 	int ret = 0;
 
-	if (!trans->nr_updates)
+	if (!trans->nr_updates &&
+	    !trans->extra_journal_entry_u64s)
 		goto out_reset;
 
 	if (trans->flags & BTREE_INSERT_GC_LOCK_HELD)
diff --git a/libbcachefs/extents.c b/libbcachefs/extents.c
index 3968f1fd..563e1305 100644
--- a/libbcachefs/extents.c
+++ b/libbcachefs/extents.c
@@ -192,9 +192,10 @@ void bch2_btree_ptr_v2_to_text(struct printbuf *out, struct bch_fs *c,
 {
 	struct bkey_s_c_btree_ptr_v2 bp = bkey_s_c_to_btree_ptr_v2(k);
 
-	pr_buf(out, "seq %llx written %u min_key ",
+	pr_buf(out, "seq %llx written %u min_key %s",
 	       le64_to_cpu(bp.v->seq),
-	       le16_to_cpu(bp.v->sectors_written));
+	       le16_to_cpu(bp.v->sectors_written),
+	       BTREE_PTR_RANGE_UPDATED(bp.v) ? "R " : "");
 
 	bch2_bpos_to_text(out, bp.v->min_key);
 	pr_buf(out, " ");
diff --git a/libbcachefs/io_types.h b/libbcachefs/io_types.h
index e7aca7c9..0aab7795 100644
--- a/libbcachefs/io_types.h
+++ b/libbcachefs/io_types.h
@@ -94,7 +94,8 @@ struct bch_write_bio {
 				bounce:1,
 				put_bio:1,
 				have_ioref:1,
-				used_mempool:1;
+				used_mempool:1,
+				first_btree_write:1;
 
 	struct bio		bio;
 };
diff --git a/libbcachefs/migrate.c b/libbcachefs/migrate.c
index aacd6385..1f65eca4 100644
--- a/libbcachefs/migrate.c
+++ b/libbcachefs/migrate.c
@@ -139,7 +139,7 @@ retry:
 				break;
 			}
 
-			ret = bch2_btree_node_update_key(&trans, iter, b, k.k);
+			ret = bch2_btree_node_update_key(&trans, iter, b, k.k, false);
 			if (ret == -EINTR) {
 				b = bch2_btree_iter_peek_node(iter);
 				ret = 0;
diff --git a/libbcachefs/recovery.c b/libbcachefs/recovery.c
index c6fa4ca3..84e224fb 100644
--- a/libbcachefs/recovery.c
+++ b/libbcachefs/recovery.c
@@ -1005,6 +1005,11 @@ int bch2_fs_recovery(struct bch_fs *c)
 		c->opts.fix_errors	= FSCK_OPT_YES;
 	}
 
+	if (c->sb.version < bcachefs_metadata_version_btree_ptr_sectors_written) {
+		bch_info(c, "version prior to btree_ptr_sectors_written, upgrade required");
+		c->opts.version_upgrade	= true;
+	}
+
 	ret = bch2_blacklist_table_initialize(c);
 	if (ret) {
 		bch_err(c, "error initializing blacklist table");
diff --git a/libbcachefs/super.c b/libbcachefs/super.c
index 13a5ca71..ce8e5d48 100644
--- a/libbcachefs/super.c
+++ b/libbcachefs/super.c
@@ -507,8 +507,8 @@ static void __bch2_fs_free(struct bch_fs *c)
 		destroy_workqueue(c->io_complete_wq );
 	if (c->copygc_wq)
 		destroy_workqueue(c->copygc_wq);
-	if (c->btree_error_wq)
-		destroy_workqueue(c->btree_error_wq);
+	if (c->btree_io_complete_wq)
+		destroy_workqueue(c->btree_io_complete_wq);
 	if (c->btree_update_wq)
 		destroy_workqueue(c->btree_update_wq);
 
@@ -560,7 +560,6 @@ void __bch2_fs_stop(struct bch_fs *c)
 	for_each_member_device(ca, c, i)
 		cancel_work_sync(&ca->io_error_work);
 
-	cancel_work_sync(&c->btree_write_error_work);
 	cancel_work_sync(&c->read_only_work);
 
 	for (i = 0; i < c->sb.nr_devices; i++)
@@ -688,9 +687,7 @@ static struct bch_fs *bch2_fs_alloc(struct bch_sb *sb, struct bch_opts opts)
 
 	mutex_init(&c->bio_bounce_pages_lock);
 
-	bio_list_init(&c->btree_write_error_list);
 	spin_lock_init(&c->btree_write_error_lock);
-	INIT_WORK(&c->btree_write_error_work, bch2_btree_write_error_work);
 
 	INIT_WORK(&c->journal_seq_blacklist_gc_work,
 		  bch2_blacklist_entries_gc);
@@ -760,7 +757,7 @@ static struct bch_fs *bch2_fs_alloc(struct bch_sb *sb, struct bch_opts opts)
 
 	if (!(c->btree_update_wq = alloc_workqueue("bcachefs",
 				WQ_FREEZABLE|WQ_MEM_RECLAIM|WQ_CPU_INTENSIVE, 1)) ||
-	    !(c->btree_error_wq = alloc_workqueue("bcachefs_error",
+	    !(c->btree_io_complete_wq = alloc_workqueue("bcachefs_btree_io",
 				WQ_FREEZABLE|WQ_MEM_RECLAIM|WQ_CPU_INTENSIVE, 1)) ||
 	    !(c->copygc_wq = alloc_workqueue("bcachefs_copygc",
 				WQ_FREEZABLE|WQ_MEM_RECLAIM|WQ_CPU_INTENSIVE, 1)) ||
diff --git a/libbcachefs/tests.c b/libbcachefs/tests.c
index 59f34b40..4d8d50fd 100644
--- a/libbcachefs/tests.c
+++ b/libbcachefs/tests.c
@@ -34,19 +34,15 @@ static int test_delete(struct bch_fs *c, u64 nr)
 	int ret;
 
 	bkey_cookie_init(&k.k_i);
+	k.k.p.snapshot = U32_MAX;
 
 	bch2_trans_init(&trans, c, 0, 0);
 
 	iter = bch2_trans_get_iter(&trans, BTREE_ID_xattrs, k.k.p,
 				   BTREE_ITER_INTENT);
 
-	ret = bch2_btree_iter_traverse(iter);
-	if (ret) {
-		bch_err(c, "lookup error in test_delete: %i", ret);
-		goto err;
-	}
-
 	ret = __bch2_trans_do(&trans, NULL, NULL, 0,
+		bch2_btree_iter_traverse(iter) ?:
 		bch2_trans_update(&trans, iter, &k.k_i, 0));
 	if (ret) {
 		bch_err(c, "update error in test_delete: %i", ret);
@@ -55,7 +51,8 @@ static int test_delete(struct bch_fs *c, u64 nr)
 
 	pr_info("deleting once");
 	ret = __bch2_trans_do(&trans, NULL, NULL, 0,
-			 bch2_btree_delete_at(&trans, iter, 0));
+		bch2_btree_iter_traverse(iter) ?:
+		bch2_btree_delete_at(&trans, iter, 0));
 	if (ret) {
 		bch_err(c, "delete error (first) in test_delete: %i", ret);
 		goto err;
@@ -63,7 +60,8 @@ static int test_delete(struct bch_fs *c, u64 nr)
 
 	pr_info("deleting twice");
 	ret = __bch2_trans_do(&trans, NULL, NULL, 0,
-			 bch2_btree_delete_at(&trans, iter, 0));
+		bch2_btree_iter_traverse(iter) ?:
+		bch2_btree_delete_at(&trans, iter, 0));
 	if (ret) {
 		bch_err(c, "delete error (second) in test_delete: %i", ret);
 		goto err;
@@ -82,29 +80,27 @@ static int test_delete_written(struct bch_fs *c, u64 nr)
 	int ret;
 
 	bkey_cookie_init(&k.k_i);
+	k.k.p.snapshot = U32_MAX;
 
 	bch2_trans_init(&trans, c, 0, 0);
 
 	iter = bch2_trans_get_iter(&trans, BTREE_ID_xattrs, k.k.p,
 				   BTREE_ITER_INTENT);
 
-	ret = bch2_btree_iter_traverse(iter);
-	if (ret) {
-		bch_err(c, "lookup error in test_delete_written: %i", ret);
-		goto err;
-	}
-
 	ret = __bch2_trans_do(&trans, NULL, NULL, 0,
+		bch2_btree_iter_traverse(iter) ?:
 		bch2_trans_update(&trans, iter, &k.k_i, 0));
 	if (ret) {
 		bch_err(c, "update error in test_delete_written: %i", ret);
 		goto err;
 	}
 
+	bch2_trans_unlock(&trans);
 	bch2_journal_flush_all_pins(&c->journal);
 
 	ret = __bch2_trans_do(&trans, NULL, NULL, 0,
-			 bch2_btree_delete_at(&trans, iter, 0));
+		bch2_btree_iter_traverse(iter) ?:
+		bch2_btree_delete_at(&trans, iter, 0));
 	if (ret) {
 		bch_err(c, "delete error in test_delete_written: %i", ret);
 		goto err;
@@ -134,6 +130,7 @@ static int test_iterate(struct bch_fs *c, u64 nr)
 
 		bkey_cookie_init(&k.k_i);
 		k.k.p.offset = i;
+		k.k.p.snapshot = U32_MAX;
 
 		ret = bch2_btree_insert(c, BTREE_ID_xattrs, &k.k_i,
 					NULL, NULL, 0);
@@ -188,6 +185,7 @@ static int test_iterate_extents(struct bch_fs *c, u64 nr)
 
 		bkey_cookie_init(&k.k_i);
 		k.k.p.offset = i + 8;
+		k.k.p.snapshot = U32_MAX;
 		k.k.size = 8;
 
 		ret = bch2_btree_insert(c, BTREE_ID_extents, &k.k_i,
@@ -243,6 +241,7 @@ static int test_iterate_slots(struct bch_fs *c, u64 nr)
 
 		bkey_cookie_init(&k.k_i);
 		k.k.p.offset = i * 2;
+		k.k.p.snapshot = U32_MAX;
 
 		ret = bch2_btree_insert(c, BTREE_ID_xattrs, &k.k_i,
 					NULL, NULL, 0);
@@ -306,6 +305,7 @@ static int test_iterate_slots_extents(struct bch_fs *c, u64 nr)
 
 		bkey_cookie_init(&k.k_i);
 		k.k.p.offset = i + 16;
+		k.k.p.snapshot = U32_MAX;
 		k.k.size = 8;
 
 		ret = bch2_btree_insert(c, BTREE_ID_extents, &k.k_i,
@@ -413,6 +413,7 @@ static int insert_test_extent(struct bch_fs *c,
 
 	bkey_cookie_init(&k.k_i);
 	k.k_i.k.p.offset = end;
+	k.k_i.k.p.snapshot = U32_MAX;
 	k.k_i.k.size = end - start;
 	k.k_i.k.version.lo = test_version++;
 
@@ -591,6 +592,7 @@ static int rand_mixed(struct bch_fs *c, u64 nr)
 			k.k.p = iter->pos;
 
 			ret = __bch2_trans_do(&trans, NULL, NULL, 0,
+				bch2_btree_iter_traverse(iter) ?:
 				bch2_trans_update(&trans, iter, &k.k_i, 0));
 			if (ret) {
 				bch_err(c, "update error in rand_mixed: %i", ret);
@@ -671,6 +673,7 @@ static int seq_insert(struct bch_fs *c, u64 nr)
 		insert.k.p = iter->pos;
 
 		ret = __bch2_trans_do(&trans, NULL, NULL, 0,
+			bch2_btree_iter_traverse(iter) ?:
 			bch2_trans_update(&trans, iter, &insert.k_i, 0));
 		if (ret) {
 			bch_err(c, "error in seq_insert: %i", ret);
@@ -719,6 +722,7 @@ static int seq_overwrite(struct bch_fs *c, u64 nr)
 		bkey_reassemble(&u.k_i, k);
 
 		ret = __bch2_trans_do(&trans, NULL, NULL, 0,
+			bch2_btree_iter_traverse(iter) ?:
 			bch2_trans_update(&trans, iter, &u.k_i, 0));
 		if (ret) {
 			bch_err(c, "error in seq_overwrite: %i", ret);