bcachefs: Kill btree_iter.trans

This was planned to be done ages ago, now finally completed; there are
places where we have quite a few btree_trans objects on the stack, so
this reduces stack usage somewhat.

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

Author: Kent Overstreet

fs/bcachefs/acl.c

@@ -273,7 +273,7 @@ struct posix_acl *bch2_get_acl(struct inode *vinode, int type, bool rcu)
 	struct bch_fs *c = inode->v.i_sb->s_fs_info;
 	struct bch_hash_info hash = bch2_hash_info_init(c, &inode->ei_inode);
 	struct xattr_search_key search = X_SEARCH(acl_to_xattr_type(type), "", 0);
-	struct btree_iter iter = { NULL };
+	struct btree_iter iter = {};
 	struct posix_acl *acl = NULL;
 
 	if (rcu)
@@ -344,7 +344,7 @@ int bch2_set_acl(struct mnt_idmap *idmap,
 {
 	struct bch_inode_info *inode = to_bch_ei(dentry->d_inode);
 	struct bch_fs *c = inode->v.i_sb->s_fs_info;
-	struct btree_iter inode_iter = { NULL };
+	struct btree_iter inode_iter = {};
 	struct bch_inode_unpacked inode_u;
 	struct posix_acl *acl;
 	umode_t mode;

fs/bcachefs/alloc_background.c

@@ -610,7 +610,7 @@ int bch2_alloc_read(struct bch_fs *c)
 			 * bch2_check_alloc_key() which runs later:
 			 */
 			if (!ca) {
-				bch2_btree_iter_set_pos(&iter, POS(k.k->p.inode + 1, 0));
+				bch2_btree_iter_set_pos(trans, &iter, POS(k.k->p.inode + 1, 0));
 				continue;
 			}
 
@@ -631,17 +631,17 @@ int bch2_alloc_read(struct bch_fs *c)
 			 * bch2_check_alloc_key() which runs later:
 			 */
 			if (!ca) {
-				bch2_btree_iter_set_pos(&iter, POS(k.k->p.inode + 1, 0));
+				bch2_btree_iter_set_pos(trans, &iter, POS(k.k->p.inode + 1, 0));
 				continue;
 			}
 
 			if (k.k->p.offset < ca->mi.first_bucket) {
-				bch2_btree_iter_set_pos(&iter, POS(k.k->p.inode, ca->mi.first_bucket));
+				bch2_btree_iter_set_pos(trans, &iter, POS(k.k->p.inode, ca->mi.first_bucket));
 				continue;
 			}
 
 			if (k.k->p.offset >= ca->mi.nbuckets) {
-				bch2_btree_iter_set_pos(&iter, POS(k.k->p.inode + 1, 0));
+				bch2_btree_iter_set_pos(trans, &iter, POS(k.k->p.inode + 1, 0));
 				continue;
 			}
 
@@ -1039,9 +1039,10 @@ int bch2_trigger_alloc(struct btree_trans *trans,
  * This synthesizes deleted extents for holes, similar to BTREE_ITER_slots for
  * extents style btrees, but works on non-extents btrees:
  */
-static struct bkey_s_c bch2_get_key_or_hole(struct btree_iter *iter, struct bpos end, struct bkey *hole)
+static struct bkey_s_c bch2_get_key_or_hole(struct btree_trans *trans, struct btree_iter *iter,
+					    struct bpos end, struct bkey *hole)
 {
-	struct bkey_s_c k = bch2_btree_iter_peek_slot(iter);
+	struct bkey_s_c k = bch2_btree_iter_peek_slot(trans, iter);
 
 	if (bkey_err(k))
 		return k;
@@ -1052,9 +1053,9 @@ static struct bkey_s_c bch2_get_key_or_hole(struct btree_iter *iter, struct bpos
 		struct btree_iter iter2;
 		struct bpos next;
 
-		bch2_trans_copy_iter(&iter2, iter);
+		bch2_trans_copy_iter(trans, &iter2, iter);
 
-		struct btree_path *path = btree_iter_path(iter->trans, iter);
+		struct btree_path *path = btree_iter_path(trans, iter);
 		if (!bpos_eq(path->l[0].b->key.k.p, SPOS_MAX))
 			end = bkey_min(end, bpos_nosnap_successor(path->l[0].b->key.k.p));
 
@@ -1064,9 +1065,9 @@ static struct bkey_s_c bch2_get_key_or_hole(struct btree_iter *iter, struct bpos
 		 * btree node min/max is a closed interval, upto takes a half
 		 * open interval:
 		 */
-		k = bch2_btree_iter_peek_max(&iter2, end);
+		k = bch2_btree_iter_peek_max(trans, &iter2, end);
 		next = iter2.pos;
-		bch2_trans_iter_exit(iter->trans, &iter2);
+		bch2_trans_iter_exit(trans, &iter2);
 
 		BUG_ON(next.offset >= iter->pos.offset + U32_MAX);
 
@@ -1107,13 +1108,14 @@ static bool next_bucket(struct bch_fs *c, struct bch_dev **ca, struct bpos *buck
 	return *ca != NULL;
 }
 
-static struct bkey_s_c bch2_get_key_or_real_bucket_hole(struct btree_iter *iter,
-					struct bch_dev **ca, struct bkey *hole)
+static struct bkey_s_c bch2_get_key_or_real_bucket_hole(struct btree_trans *trans,
+							struct btree_iter *iter,
+							struct bch_dev **ca, struct bkey *hole)
 {
-	struct bch_fs *c = iter->trans->c;
+	struct bch_fs *c = trans->c;
 	struct bkey_s_c k;
 again:
-	k = bch2_get_key_or_hole(iter, POS_MAX, hole);
+	k = bch2_get_key_or_hole(trans, iter, POS_MAX, hole);
 	if (bkey_err(k))
 		return k;
 
@@ -1126,7 +1128,7 @@ static struct bkey_s_c bch2_get_key_or_real_bucket_hole(struct btree_iter *iter,
 			if (!next_bucket(c, ca, &hole_start))
 				return bkey_s_c_null;
 
-			bch2_btree_iter_set_pos(iter, hole_start);
+			bch2_btree_iter_set_pos(trans, iter, hole_start);
 			goto again;
 		}
 
@@ -1167,8 +1169,8 @@ int bch2_check_alloc_key(struct btree_trans *trans,
 
 	a = bch2_alloc_to_v4(alloc_k, &a_convert);
 
-	bch2_btree_iter_set_pos(discard_iter, alloc_k.k->p);
-	k = bch2_btree_iter_peek_slot(discard_iter);
+	bch2_btree_iter_set_pos(trans, discard_iter, alloc_k.k->p);
+	k = bch2_btree_iter_peek_slot(trans, discard_iter);
 	ret = bkey_err(k);
 	if (ret)
 		goto err;
@@ -1181,8 +1183,8 @@ int bch2_check_alloc_key(struct btree_trans *trans,
 			goto err;
 	}
 
-	bch2_btree_iter_set_pos(freespace_iter, alloc_freespace_pos(alloc_k.k->p, *a));
-	k = bch2_btree_iter_peek_slot(freespace_iter);
+	bch2_btree_iter_set_pos(trans, freespace_iter, alloc_freespace_pos(alloc_k.k->p, *a));
+	k = bch2_btree_iter_peek_slot(trans, freespace_iter);
 	ret = bkey_err(k);
 	if (ret)
 		goto err;
@@ -1195,8 +1197,8 @@ int bch2_check_alloc_key(struct btree_trans *trans,
 			goto err;
 	}
 
-	bch2_btree_iter_set_pos(bucket_gens_iter, alloc_gens_pos(alloc_k.k->p, &gens_offset));
-	k = bch2_btree_iter_peek_slot(bucket_gens_iter);
+	bch2_btree_iter_set_pos(trans, bucket_gens_iter, alloc_gens_pos(alloc_k.k->p, &gens_offset));
+	k = bch2_btree_iter_peek_slot(trans, bucket_gens_iter);
 	ret = bkey_err(k);
 	if (ret)
 		goto err;
@@ -1249,9 +1251,9 @@ int bch2_check_alloc_hole_freespace(struct btree_trans *trans,
 	if (!ca->mi.freespace_initialized)
 		return 0;
 
-	bch2_btree_iter_set_pos(freespace_iter, start);
+	bch2_btree_iter_set_pos(trans, freespace_iter, start);
 
-	k = bch2_btree_iter_peek_slot(freespace_iter);
+	k = bch2_btree_iter_peek_slot(trans, freespace_iter);
 	ret = bkey_err(k);
 	if (ret)
 		goto err;
@@ -1300,9 +1302,9 @@ int bch2_check_alloc_hole_bucket_gens(struct btree_trans *trans,
 	unsigned i, gens_offset, gens_end_offset;
 	int ret;
 
-	bch2_btree_iter_set_pos(bucket_gens_iter, alloc_gens_pos(start, &gens_offset));
+	bch2_btree_iter_set_pos(trans, bucket_gens_iter, alloc_gens_pos(start, &gens_offset));
 
-	k = bch2_btree_iter_peek_slot(bucket_gens_iter);
+	k = bch2_btree_iter_peek_slot(trans, bucket_gens_iter);
 	ret = bkey_err(k);
 	if (ret)
 		goto err;
@@ -1435,7 +1437,7 @@ int bch2_check_discard_freespace_key(struct btree_trans *trans, struct btree_ite
 	*gen = a->gen;
 out:
 fsck_err:
-	bch2_set_btree_iter_dontneed(&alloc_iter);
+	bch2_set_btree_iter_dontneed(trans, &alloc_iter);
 	bch2_trans_iter_exit(trans, &alloc_iter);
 	printbuf_exit(&buf);
 	return ret;
@@ -1572,7 +1574,7 @@ int bch2_check_alloc_info(struct bch_fs *c)
 
 		bch2_trans_begin(trans);
 
-		k = bch2_get_key_or_real_bucket_hole(&iter, &ca, &hole);
+		k = bch2_get_key_or_real_bucket_hole(trans, &iter, &ca, &hole);
 		ret = bkey_err(k);
 		if (ret)
 			goto bkey_err;
@@ -1610,7 +1612,7 @@ int bch2_check_alloc_info(struct bch_fs *c)
 		if (ret)
 			goto bkey_err;
 
-		bch2_btree_iter_set_pos(&iter, next);
+		bch2_btree_iter_set_pos(trans, &iter, next);
 bkey_err:
 		if (bch2_err_matches(ret, BCH_ERR_transaction_restart))
 			continue;
@@ -1638,7 +1640,7 @@ int bch2_check_alloc_info(struct bch_fs *c)
 			     BTREE_ITER_prefetch);
 	while (1) {
 		bch2_trans_begin(trans);
-		k = bch2_btree_iter_peek(&iter);
+		k = bch2_btree_iter_peek(trans, &iter);
 		if (!k.k)
 			break;
 
@@ -1657,7 +1659,7 @@ int bch2_check_alloc_info(struct bch_fs *c)
 			break;
 		}
 
-		bch2_btree_iter_set_pos(&iter, bpos_nosnap_successor(iter.pos));
+		bch2_btree_iter_set_pos(trans, &iter, bpos_nosnap_successor(iter.pos));
 	}
 	bch2_trans_iter_exit(trans, &iter);
 	if (ret)
@@ -1685,7 +1687,7 @@ static int bch2_check_alloc_to_lru_ref(struct btree_trans *trans,
 	struct printbuf buf = PRINTBUF;
 	int ret;
 
-	alloc_k = bch2_btree_iter_peek(alloc_iter);
+	alloc_k = bch2_btree_iter_peek(trans, alloc_iter);
 	if (!alloc_k.k)
 		return 0;
 
@@ -1826,7 +1828,7 @@ static int bch2_discard_one_bucket(struct btree_trans *trans,
 {
 	struct bch_fs *c = trans->c;
 	struct bpos pos = need_discard_iter->pos;
-	struct btree_iter iter = { NULL };
+	struct btree_iter iter = {};
 	struct bkey_s_c k;
 	struct bkey_i_alloc_v4 *a;
 	struct printbuf buf = PRINTBUF;
@@ -2199,9 +2201,9 @@ static struct bkey_s_c next_lru_key(struct btree_trans *trans, struct btree_iter
 {
 	struct bkey_s_c k;
 again:
-	k = bch2_btree_iter_peek_max(iter, lru_pos(ca->dev_idx, U64_MAX, LRU_TIME_MAX));
+	k = bch2_btree_iter_peek_max(trans, iter, lru_pos(ca->dev_idx, U64_MAX, LRU_TIME_MAX));
 	if (!k.k && !*wrapped) {
-		bch2_btree_iter_set_pos(iter, lru_pos(ca->dev_idx, 0, 0));
+		bch2_btree_iter_set_pos(trans, iter, lru_pos(ca->dev_idx, 0, 0));
 		*wrapped = true;
 		goto again;
 	}
@@ -2251,7 +2253,7 @@ static void bch2_do_invalidates_work(struct work_struct *work)
 		if (ret)
 			break;
 
-		bch2_btree_iter_advance(&iter);
+		bch2_btree_iter_advance(trans, &iter);
 	}
 	bch2_trans_iter_exit(trans, &iter);
 err:
@@ -2321,7 +2323,7 @@ int bch2_dev_freespace_init(struct bch_fs *c, struct bch_dev *ca,
 			break;
 		}
 
-		k = bch2_get_key_or_hole(&iter, end, &hole);
+		k = bch2_get_key_or_hole(trans, &iter, end, &hole);
 		ret = bkey_err(k);
 		if (ret)
 			goto bkey_err;
@@ -2340,7 +2342,7 @@ int bch2_dev_freespace_init(struct bch_fs *c, struct bch_dev *ca,
 			if (ret)
 				goto bkey_err;
 
-			bch2_btree_iter_advance(&iter);
+			bch2_btree_iter_advance(trans, &iter);
 		} else {
 			struct bkey_i *freespace;
 
@@ -2360,7 +2362,7 @@ int bch2_dev_freespace_init(struct bch_fs *c, struct bch_dev *ca,
 			if (ret)
 				goto bkey_err;
 
-			bch2_btree_iter_set_pos(&iter, k.k->p);
+			bch2_btree_iter_set_pos(trans, &iter, k.k->p);
 		}
 bkey_err:
 		if (bch2_err_matches(ret, BCH_ERR_transaction_restart))

fs/bcachefs/alloc_foreground.c

@@ -327,7 +327,7 @@ bch2_bucket_alloc_early(struct btree_trans *trans,
 			bucket = sector_to_bucket(ca,
 					round_up(bucket_to_sector(ca, bucket) + 1,
 						 1ULL << ca->mi.btree_bitmap_shift));
-			bch2_btree_iter_set_pos(&iter, POS(ca->dev_idx, bucket));
+			bch2_btree_iter_set_pos(trans, &iter, POS(ca->dev_idx, bucket));
 			s->buckets_seen++;
 			s->skipped_mi_btree_bitmap++;
 			continue;
@@ -355,7 +355,7 @@ bch2_bucket_alloc_early(struct btree_trans *trans,
 					     watermark, s, cl)
 			: NULL;
 next:
-		bch2_set_btree_iter_dontneed(&citer);
+		bch2_set_btree_iter_dontneed(trans, &citer);
 		bch2_trans_iter_exit(trans, &citer);
 		if (ob)
 			break;
@@ -417,7 +417,7 @@ static struct open_bucket *bch2_bucket_alloc_freelist(struct btree_trans *trans,
 							 1ULL << ca->mi.btree_bitmap_shift));
 				alloc_cursor = bucket|(iter.pos.offset & (~0ULL << 56));
 
-				bch2_btree_iter_set_pos(&iter, POS(ca->dev_idx, alloc_cursor));
+				bch2_btree_iter_set_pos(trans, &iter, POS(ca->dev_idx, alloc_cursor));
 				s->skipped_mi_btree_bitmap++;
 				goto next;
 			}
@@ -426,7 +426,7 @@ static struct open_bucket *bch2_bucket_alloc_freelist(struct btree_trans *trans,
 			if (ob) {
 				if (!IS_ERR(ob))
 					*dev_alloc_cursor = iter.pos.offset;
-				bch2_set_btree_iter_dontneed(&iter);
+				bch2_set_btree_iter_dontneed(trans, &iter);
 				break;
 			}
 

fs/bcachefs/backpointers.c

@@ -252,7 +252,7 @@ struct bkey_s_c bch2_backpointer_get_key(struct btree_trans *trans,
 				  0,
 				  bp.v->level,
 				  iter_flags);
-	struct bkey_s_c k = bch2_btree_iter_peek_slot(iter);
+	struct bkey_s_c k = bch2_btree_iter_peek_slot(trans, iter);
 	if (bkey_err(k)) {
 		bch2_trans_iter_exit(trans, iter);
 		return k;
@@ -293,7 +293,7 @@ struct btree *bch2_backpointer_get_node(struct btree_trans *trans,
 				  0,
 				  bp.v->level - 1,
 				  0);
-	struct btree *b = bch2_btree_iter_peek_node(iter);
+	struct btree *b = bch2_btree_iter_peek_node(trans, iter);
 	if (IS_ERR_OR_NULL(b))
 		goto err;
 
@@ -321,7 +321,7 @@ static int bch2_check_backpointer_has_valid_bucket(struct btree_trans *trans, st
 		return 0;
 
 	struct bch_fs *c = trans->c;
-	struct btree_iter alloc_iter = { NULL };
+	struct btree_iter alloc_iter = {};
 	struct bkey_s_c alloc_k;
 	struct printbuf buf = PRINTBUF;
 	int ret = 0;
@@ -650,7 +650,7 @@ static int check_btree_root_to_backpointers(struct btree_trans *trans,
 retry:
 	bch2_trans_node_iter_init(trans, &iter, btree_id, POS_MIN,
 				  0, bch2_btree_id_root(c, btree_id)->b->c.level, 0);
-	b = bch2_btree_iter_peek_node(&iter);
+	b = bch2_btree_iter_peek_node(trans, &iter);
 	ret = PTR_ERR_OR_ZERO(b);
 	if (ret)
 		goto err;
@@ -934,7 +934,7 @@ static int btree_node_get_and_pin(struct btree_trans *trans, struct bkey_i *k,
 {
 	struct btree_iter iter;
 	bch2_trans_node_iter_init(trans, &iter, btree, k->k.p, 0, level, 0);
-	struct btree *b = bch2_btree_iter_peek_node(&iter);
+	struct btree *b = bch2_btree_iter_peek_node(trans, &iter);
 	int ret = PTR_ERR_OR_ZERO(b);
 	if (ret)
 		goto err;

fs/bcachefs/btree_gc.c

@@ -691,7 +691,7 @@ static int bch2_gc_btree(struct btree_trans *trans,
 		struct btree_iter iter;
 		bch2_trans_node_iter_init(trans, &iter, btree, POS_MIN,
 					  0, bch2_btree_id_root(c, btree)->b->c.level, 0);
-		struct btree *b = bch2_btree_iter_peek_node(&iter);
+		struct btree *b = bch2_btree_iter_peek_node(trans, &iter);
 		ret = PTR_ERR_OR_ZERO(b);
 		if (ret)
 			goto err_root;
@@ -1199,7 +1199,7 @@ int bch2_gc_gens(struct bch_fs *c)
 				BCH_TRANS_COMMIT_no_enospc, ({
 			ca = bch2_dev_iterate(c, ca, k.k->p.inode);
 			if (!ca) {
-				bch2_btree_iter_set_pos(&iter, POS(k.k->p.inode + 1, 0));
+				bch2_btree_iter_set_pos(trans, &iter, POS(k.k->p.inode + 1, 0));
 				continue;
 			}
 			bch2_alloc_write_oldest_gen(trans, ca, &iter, k);

fs/bcachefs/btree_io.c

@@ -1909,7 +1909,8 @@ static void btree_node_scrub_work(struct work_struct *work)
 					  scrub->key.k->k.p, 0, scrub->level - 1, 0);
 
 		struct btree *b;
-		int ret = lockrestart_do(trans, PTR_ERR_OR_ZERO(b = bch2_btree_iter_peek_node(&iter)));
+		int ret = lockrestart_do(trans,
+			PTR_ERR_OR_ZERO(b = bch2_btree_iter_peek_node(trans, &iter)));
 		if (ret)
 			goto err;