+/*
+ * We use an encoding that preserves the times for extra epoch "00":
+ *
+ * extra msb of adjust for signed
+ * epoch 32-bit 32-bit tv_sec to
+ * bits time decoded 64-bit tv_sec 64-bit tv_sec valid time range
+ * 0 0 1 -0x80000000..-0x00000001 0x000000000 1901-12-13..1969-12-31
+ * 0 0 0 0x000000000..0x07fffffff 0x000000000 1970-01-01..2038-01-19
+ * 0 1 1 0x080000000..0x0ffffffff 0x100000000 2038-01-19..2106-02-07
+ * 0 1 0 0x100000000..0x17fffffff 0x100000000 2106-02-07..2174-02-25
+ * 1 0 1 0x180000000..0x1ffffffff 0x200000000 2174-02-25..2242-03-16
+ * 1 0 0 0x200000000..0x27fffffff 0x200000000 2242-03-16..2310-04-04
+ * 1 1 1 0x280000000..0x2ffffffff 0x300000000 2310-04-04..2378-04-22
+ * 1 1 0 0x300000000..0x37fffffff 0x300000000 2378-04-22..2446-05-10
+ *
+ * Note that previous versions of the kernel on 64-bit systems would
+ * incorrectly use extra epoch bits 1,1 for dates between 1901 and
+ * 1970. e2fsck will correct this, assuming that it is run on the
+ * affected filesystem before 2242.
+ */
+