block: do not artificially constrain max_sectors for stacking drivers
authorMike Snitzer <snitzer@redhat.com>
Wed, 1 Aug 2012 08:44:28 +0000 (10:44 +0200)
committerJens Axboe <axboe@kernel.dk>
Wed, 1 Aug 2012 08:44:28 +0000 (10:44 +0200)
commitfe86cdcef73ba19a2246a124f0ddbd19b14fb549
tree3e947ceddc7ffb9073c2b7c3797cdf0d2e1c833a
parenta051661ca6d134c18599498b185b667859d4339b
block: do not artificially constrain max_sectors for stacking drivers

blk_set_stacking_limits is intended to allow stacking drivers to build
up the limits of the stacked device based on the underlying devices'
limits.  But defaulting 'max_sectors' to BLK_DEF_MAX_SECTORS (1024)
doesn't allow the stacking driver to inherit a max_sectors larger than
1024 -- due to blk_stack_limits' use of min_not_zero.

It is now clear that this artificial limit is getting in the way so
change blk_set_stacking_limits's max_sectors to UINT_MAX (which allows
stacking drivers like dm-multipath to inherit 'max_sectors' from the
underlying paths).

Reported-by: Vijay Chauhan <vijay.chauhan@netapp.com>
Tested-by: Vijay Chauhan <vijay.chauhan@netapp.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
block/blk-settings.c