bcachefs: bkey noops

For upcoming inline data extents, we're going to need to be able to
shorten the value of existing bkeys in the btree - and to make that work
we're going to be able to need to pad out the space the value previously
took up with something.

This patch changes the various code that iterates over bkeys to handle
k->u64s == 0 as meaning "skip the next 8 bytes".

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

1 files changed, 21 insertions, 19 deletions

diff --git a/fs/bcachefs/bset.c b/fs/bcachefs/bset.c
index af20b9803608..189a187bc080 100644
--- a/fs/bcachefs/bset.c
+++ b/fs/bcachefs/bset.c
@@ -64,7 +64,7 @@ void bch2_dump_bset(struct btree *b, struct bset *i, unsigned set)
 	for (_k = i->start, k = bkey_unpack_key(b, _k);
 	     _k < vstruct_last(i);
 	     _k = _n, k = n) {
-		_n = bkey_next(_k);
+		_n = bkey_next_skip_noops(_k, vstruct_last(i));
 
 		bch2_bkey_to_text(&PBUF(buf), &k);
 		printk(KERN_ERR "block %u key %5u: %s\n", set,
@@ -132,9 +132,7 @@ void __bch2_verify_btree_nr_keys(struct btree *b)
 	struct btree_nr_keys nr = { 0 };
 
 	for_each_bset(b, t)
-		for (k = btree_bkey_first(b, t);
-		     k != btree_bkey_last(b, t);
-		     k = bkey_next(k))
+		bset_tree_for_each_key(b, t, k)
 			if (!bkey_whiteout(k))
 				btree_keys_account_key_add(&nr, t - b->set, k);
 
@@ -595,7 +593,7 @@ start:
 			       rw_aux_tree(b, t)[j - 1].offset);
 		}
 
-		k = bkey_next(k);
+		k = bkey_next_skip_noops(k, btree_bkey_last(b, t));
 		BUG_ON(k >= btree_bkey_last(b, t));
 	}
 }
@@ -786,9 +784,7 @@ static void __build_rw_aux_tree(struct btree *b, struct bset_tree *t)
 	rw_aux_tree(b, t)[0].offset =
 		__btree_node_key_to_offset(b, btree_bkey_first(b, t));
 
-	for (k = btree_bkey_first(b, t);
-	     k != btree_bkey_last(b, t);
-	     k = bkey_next(k)) {
+	bset_tree_for_each_key(b, t, k) {
 		if (t->size == bset_rw_tree_capacity(b, t))
 			break;
 
@@ -821,7 +817,7 @@ retry:
 	/* First we figure out where the first key in each cacheline is */
 	eytzinger1_for_each(j, t->size) {
 		while (bkey_to_cacheline(b, t, k) < cacheline)
-			prev = k, k = bkey_next(k);
+			prev = k, k = bkey_next_skip_noops(k, btree_bkey_last(b, t));
 
 		if (k >= btree_bkey_last(b, t)) {
 			/* XXX: this path sucks */
@@ -837,10 +833,10 @@ retry:
 		EBUG_ON(tree_to_bkey(b, t, j) != k);
 	}
 
-	while (bkey_next(k) != btree_bkey_last(b, t))
-		k = bkey_next(k);
+	while (k != btree_bkey_last(b, t))
+		prev = k, k = bkey_next_skip_noops(k, btree_bkey_last(b, t));
 
-	t->max_key = bkey_unpack_pos(b, k);
+	t->max_key = bkey_unpack_pos(b, prev);
 
 	/* Then we build the tree */
 	eytzinger1_for_each(j, t->size)
@@ -966,7 +962,7 @@ struct bkey_packed *bch2_bkey_prev_filter(struct btree *b,
 	struct bkey_packed *p, *i, *ret = NULL, *orig_k = k;
 
 	while ((p = __bkey_prev(b, t, k)) && !ret) {
-		for (i = p; i != k; i = bkey_next(i))
+		for (i = p; i != k; i = bkey_next_skip_noops(i, k))
 			if (i->type >= min_key_type)
 				ret = i;
 
@@ -976,9 +972,11 @@ struct bkey_packed *bch2_bkey_prev_filter(struct btree *b,
 	if (btree_keys_expensive_checks(b)) {
 		BUG_ON(ret >= orig_k);
 
-		for (i = ret ? bkey_next(ret) : btree_bkey_first(b, t);
+		for (i = ret
+			? bkey_next_skip_noops(ret, orig_k)
+			: btree_bkey_first(b, t);
 		     i != orig_k;
-		     i = bkey_next(i))
+		     i = bkey_next_skip_noops(i, orig_k))
 			BUG_ON(i->type >= min_key_type);
 	}
 
@@ -1013,7 +1011,7 @@ static void ro_aux_tree_fix_invalidated_key(struct btree *b,
 	/* signal to make_bfloat() that they're uninitialized: */
 	min_key.u64s = max_key.u64s = 0;
 
-	if (bkey_next(k) == btree_bkey_last(b, t)) {
+	if (bkey_next_skip_noops(k, btree_bkey_last(b, t)) == btree_bkey_last(b, t)) {
 		t->max_key = bkey_unpack_pos(b, k);
 
 		for (j = 1; j < t->size; j = j * 2 + 1)
@@ -1137,7 +1135,7 @@ static void bch2_bset_fix_lookup_table(struct btree *b,
 		struct bkey_packed *k = start;
 
 		while (1) {
-			k = bkey_next(k);
+			k = bkey_next_skip_noops(k, end);
 			if (k == end)
 				break;
 
@@ -1386,12 +1384,12 @@ struct bkey_packed *bch2_bset_search_linear(struct btree *b,
 		while (m != btree_bkey_last(b, t) &&
 		       bkey_iter_cmp_p_or_unp(b, search, lossy_packed_search,
 					      m) > 0)
-			m = bkey_next(m);
+			m = bkey_next_skip_noops(m, btree_bkey_last(b, t));
 
 	if (!packed_search)
 		while (m != btree_bkey_last(b, t) &&
 		       bkey_iter_pos_cmp(b, search, m) > 0)
-			m = bkey_next(m);
+			m = bkey_next_skip_noops(m, btree_bkey_last(b, t));
 
 	if (btree_keys_expensive_checks(b)) {
 		struct bkey_packed *prev = bch2_bkey_prev_all(b, t, m);
@@ -1625,6 +1623,10 @@ static inline void __bch2_btree_node_iter_advance(struct btree_node_iter *iter,
 
 	EBUG_ON(iter->data->k > iter->data->end);
 
+	while (!__btree_node_iter_set_end(iter, 0) &&
+	       !__bch2_btree_node_iter_peek_all(iter, b)->u64s)
+		iter->data->k++;
+
 	if (unlikely(__btree_node_iter_set_end(iter, 0))) {
 		bch2_btree_node_iter_set_drop(iter, iter->data);
 		return;