md/raid5: avoid reading parity blocks for full-stripe write to degraded array
authorNeilBrown <neilb@suse.de>
Fri, 8 May 2015 08:19:33 +0000 (18:19 +1000)
committerNeilBrown <neilb@suse.de>
Fri, 8 May 2015 08:47:17 +0000 (18:47 +1000)
commit10d82c5f0d167ef75a2d8d7d4eed9ee43d3369c9
tree0aa8aa74575cd2ff2028030fb830a8e73f5574c6
parentb0c783b32318bef29d64086fa812e8c659cb5b37
md/raid5: avoid reading parity blocks for full-stripe write to degraded array

When performing a reconstruct write, we need to read all blocks
that are not being over-written .. except the parity (P and Q) blocks.

The code currently reads these (as they are not being over-written!)
unnecessarily.

Signed-off-by: NeilBrown <neilb@suse.de>
Fixes: ea664c8245f3 ("md/raid5: need_this_block: tidy/fix last condition.")
drivers/md/raid5.c