bcachefs: Fix iterator overflow in move path

The move path was calling bch2_bucket_io_time_reset() for cached
pointers (which it shouldn't have been), and then not calling
bch2_trans_reset() when it got -EINTR (indicating transaction restart).
Oops.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

fs/bcachefs/io.c

@@ -2202,7 +2202,11 @@ int __bch2_read_extent(struct btree_trans *trans, struct bch_read_bio *orig,
 
 	bch2_increment_clock(c, bio_sectors(&rbio->bio), READ);
 
-	if (pick.ptr.cached)
+	/*
+	 * If it's being moved internally, we don't want to flag it as a cache
+	 * hit:
+	 */
+	if (pick.ptr.cached && !(flags & BCH_READ_NODECODE))
 		bch2_bucket_io_time_reset(trans, pick.ptr.dev,
 			PTR_BUCKET_NR(ca, &pick.ptr), READ);
 

fs/bcachefs/move.c

@@ -611,6 +611,12 @@ static int __bch2_move_data(struct bch_fs *c,
 		ret2 = bch2_move_extent(&trans, ctxt, wp, io_opts, btree_id, k,
 					data_cmd, data_opts);
 		if (ret2) {
+			if (ret2 == -EINTR) {
+				bch2_trans_reset(&trans, 0);
+				bch2_trans_cond_resched(&trans);
+				continue;
+			}
+
 			if (ret2 == -ENOMEM) {
 				/* memory allocation failure, wait for some IO to finish */
 				bch2_move_ctxt_wait_for_io(ctxt);