blk-mq: rework flush sequencing logic
authorChristoph Hellwig <hch@lst.de>
Mon, 10 Feb 2014 16:29:00 +0000 (09:29 -0700)
committerJens Axboe <axboe@fb.com>
Mon, 10 Feb 2014 16:29:00 +0000 (09:29 -0700)
commit18741986a4b1dc4b1f171634c4191abc3b0fa023
treed0f632fa9b205d5fbcc76ff1cf8cba63112c7da8
parentce2c350b2cfe5b5ca5023a6b1ec4d21821d39add
blk-mq: rework flush sequencing logic

Witch to using a preallocated flush_rq for blk-mq similar to what's done
with the old request path.  This allows us to set up the request properly
with a tag from the actually allowed range and ->rq_disk as needed by
some drivers.  To make life easier we also switch to dynamic allocation
of ->flush_rq for the old path.

This effectively reverts most of

    "blk-mq: fix for flush deadlock"

and

    "blk-mq: Don't reserve a tag for flush request"

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
block/blk-core.c
block/blk-flush.c
block/blk-mq.c
block/blk-mq.h
block/blk-sysfs.c
include/linux/blk-mq.h
include/linux/blkdev.h