bcachefs: bch2_trans_reset() calls should be at the tops of loops

It needs to be called when we get -EINTR due to e.g. lock restart - this
fixes a transaction iterators overflow bug.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

fs/bcachefs/btree_iter.h

@@ -299,11 +299,6 @@ static inline void bch2_trans_begin(struct btree_trans *trans)
 	return bch2_trans_reset(trans, TRANS_RESET_ITERS|TRANS_RESET_MEM);
 }
 
-static inline void bch2_trans_begin_updates(struct btree_trans *trans)
-{
-	return bch2_trans_reset(trans, TRANS_RESET_MEM);
-}
-
 void *bch2_trans_kmalloc(struct btree_trans *, size_t);
 void bch2_trans_init(struct btree_trans *, struct bch_fs *, unsigned, size_t);
 int bch2_trans_exit(struct btree_trans *);

fs/bcachefs/btree_update_leaf.c

@@ -869,6 +869,8 @@ int bch2_btree_delete_at_range(struct btree_trans *trans,
 	       bkey_cmp(iter->pos, end) < 0) {
 		struct bkey_i delete;
 
+		bch2_trans_reset(trans, TRANS_RESET_MEM);
+
 		bkey_init(&delete.k);
 
 		/*

fs/bcachefs/fs-io.c

@@ -2650,6 +2650,8 @@ static long bchfs_fallocate(struct bch_inode_info *inode, int mode,
 		struct bkey_i_reservation reservation;
 		struct bkey_s_c k;
 
+		bch2_trans_reset(&trans, TRANS_RESET_MEM);
+
 		k = bch2_btree_iter_peek_slot(iter);
 		if ((ret = bkey_err(k)))
 			goto bkey_err;
@@ -2696,8 +2698,6 @@ static long bchfs_fallocate(struct bch_inode_info *inode, int mode,
 			reservation.v.nr_replicas = disk_res.nr_replicas;
 		}
 
-		bch2_trans_begin_updates(&trans);
-
 		ret = bch2_extent_update(&trans, iter, &reservation.k_i,
 				&disk_res, &inode->ei_journal_seq,
 				0, &i_sectors_delta);

fs/bcachefs/io.c

@@ -336,6 +336,8 @@ int bch2_fpunch_at(struct btree_trans *trans, struct btree_iter *iter,
 			bch2_disk_reservation_init(c, 0);
 		struct bkey_i delete;
 
+		bch2_trans_reset(trans, TRANS_RESET_MEM);
+
 		ret = bkey_err(k);
 		if (ret)
 			goto btree_err;
@@ -347,8 +349,6 @@ int bch2_fpunch_at(struct btree_trans *trans, struct btree_iter *iter,
 		bch2_key_resize(&delete.k, max_sectors);
 		bch2_cut_back(end, &delete);
 
-		bch2_trans_begin_updates(trans);
-
 		ret = bch2_extent_update(trans, iter, &delete,
 				&disk_res, journal_seq,
 				0, i_sectors_delta);
@@ -410,14 +410,14 @@ int bch2_write_index_default(struct bch_write_op *op)
 				   BTREE_ITER_SLOTS|BTREE_ITER_INTENT);
 
 	do {
+		bch2_trans_reset(&trans, TRANS_RESET_MEM);
+
 		k = bch2_keylist_front(keys);
 
 		bkey_on_stack_realloc(&sk, c, k->k.u64s);
 		bkey_copy(sk.k, k);
 		bch2_cut_front(iter->pos, sk.k);
 
-		bch2_trans_begin_updates(&trans);
-
 		ret = bch2_extent_update(&trans, iter, sk.k,
 					 &op->res, op_journal_seq(op),
 					 op->new_i_size, &op->i_sectors_delta);

fs/bcachefs/reflink.c

@@ -185,7 +185,8 @@ s64 bch2_remap_range(struct bch_fs *c,
 				       BTREE_ITER_INTENT);
 
 	while (1) {
-		bch2_trans_begin_updates(&trans);
+		bch2_trans_reset(&trans, TRANS_RESET_MEM);
+
 		trans.mem_top = 0;
 
 		if (fatal_signal_pending(current)) {