block: Invalidate cache on discard v2
authorDmitry Monakhov <dmonakhov@openvz.org>
Wed, 25 Oct 2017 00:44:57 +0000 (18:44 -0600)
committerJens Axboe <axboe@kernel.dk>
Wed, 25 Oct 2017 00:44:57 +0000 (18:44 -0600)
commit351499a172c0c5fc52d65ee2c62b344f369ea02a
treef4ae426a9204fe49711a0d79f57d825fc7063706
parent75bc5f06617fe1bc9a79ba9e3baccdcae3743404
block: Invalidate cache on discard v2

It is reasonable drop page cache on discard, otherwise that pages may
be written by writeback second later, so thin provision devices will
not be happy. This seems to be a  security leak in case of secure discard case.

Also add check for queue_discard flag on early stage.

Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
block/ioctl.c