libnvdimm, btt: ensure that flags were also unchanged during a map_read
authorVishal Verma <vishal.l.verma@intel.com>
Thu, 31 Aug 2017 01:36:00 +0000 (19:36 -0600)
committerDan Williams <dan.j.williams@intel.com>
Thu, 31 Aug 2017 22:05:10 +0000 (15:05 -0700)
commit1398199d849047c59acef0c04e550b47bb9b4be6
treeea1bbf44a70de941d70b71007aec836993dfc98f
parent0595d539a5deb4f495618ebbed96db59ae635e32
libnvdimm, btt: ensure that flags were also unchanged during a map_read

In btt_map_read, we read the map twice to make sure that the map entry
didn't change after we added it to the read tracking table. In
anticipation of expanding the use of the error bit, also make sure that
the error and zero flags are constant across the two map reads.

Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
drivers/nvdimm/btt.c