dm: split request structure out from dm_rq_target_io structure
authorMike Snitzer <snitzer@redhat.com>
Fri, 5 Dec 2014 22:11:05 +0000 (17:11 -0500)
committerMike Snitzer <snitzer@redhat.com>
Mon, 9 Feb 2015 18:06:47 +0000 (13:06 -0500)
commit1ae49ea2cf3ef097d4496981261a400f1f988b84
tree816a2c908e575cc31c55af8a1cfec5dcee65e5e9
parentdbf9782c1078c537831201c73ac60c9623ae9370
dm: split request structure out from dm_rq_target_io structure

Request-based DM support for blk-mq devices requires that
dm_rq_target_io structures not be allocated with an embedded request
structure.  The request-based DM target (e.g. dm-multipath) must
allocate the request from the blk-mq devices' request_queue using
blk_get_request().

The unfortunate side-effect of this change is old-style request-based DM
support will no longer use contiguous memory for the dm_rq_target_io and
request structures for each clone.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
drivers/md/dm.c