bcachefs: Improve fs_usage_apply_warn() message

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

fs/bcachefs/buckets.c

@@ -1276,23 +1276,24 @@ void fs_usage_apply_warn(struct btree_trans *trans,
 	struct btree_insert_entry *i;
 	struct printbuf buf = PRINTBUF;
 
-	bch_err(c, "disk usage increased %lli more than %u sectors reserved",
+	prt_printf(&buf,
+		   bch2_fmt(c, "disk usage increased %lli more than %u sectors reserved)"),
 		   should_not_have_added, disk_res_sectors);
 
 	trans_for_each_update(trans, i) {
 		struct bkey_s_c old = { &i->old_k, i->old_v };
 
-		pr_err("while inserting");
-		printbuf_reset(&buf);
+		prt_str(&buf, "new ");
 		bch2_bkey_val_to_text(&buf, c, bkey_i_to_s_c(i->k));
-		pr_err("  %s", buf.buf);
-		pr_err("overlapping with");
-		printbuf_reset(&buf);
+		prt_newline(&buf);
+
+		prt_str(&buf, "old ");
 		bch2_bkey_val_to_text(&buf, c, old);
-		pr_err("  %s", buf.buf);
+		prt_newline(&buf);
 	}
 
 	__WARN();
+	bch2_print_string_as_lines(KERN_ERR, buf.buf);
 	printbuf_exit(&buf);
 }