block: Fix computation of merged request priority
authorJan Kara <jack@suse.cz>
Thu, 30 Oct 2014 19:43:38 +0000 (20:43 +0100)
committerJens Axboe <axboe@fb.com>
Fri, 31 Oct 2014 14:30:43 +0000 (08:30 -0600)
commitece9c72accdc45c3a9484dacb1125ce572647288
tree9951eb6b877628b60562f4cc5ee80099f501d736
parent3a2f22b7d0cc64482a91529e23c2570aa0602fa6
block: Fix computation of merged request priority

Priority of a merged request is computed by ioprio_best(). If one of the
requests has undefined priority (IOPRIO_CLASS_NONE) and another request
has priority from IOPRIO_CLASS_BE, the function will return the
undefined priority which is wrong. Fix the function to properly return
priority of a request with the defined priority.

Fixes: d58cdfb89ce0c6bd5f81ae931a984ef298dbda20
CC: stable@vger.kernel.org
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
block/ioprio.c