tree 71e364c57887213431143e6fd1296e8433cc6293
parent 2e61ebbcc45438899235d7a39f17291cb24e746c
author NeilBrown <neilb@suse.de> 1324595870 +1100
committer NeilBrown <neilb@suse.de> 1324595870 +1100

md/raid5: be more thorough in calculating 'degraded' value.

When an array is being reshaped to change the number of devices,
the two halves can be differently degraded.  e.g. one could be
missing a device and the other not.

So we need to be more careful about calculating the 'degraded'
attribute.

Instead of just inc/dec at appropriate times, perform a full
re-calculation examining both possible cases.  This doesn't happen
often so it not a big cost, and we already have most of the code to
do it.

Signed-off-by: NeilBrown <neilb@suse.de>