With current SPDK_BDEV_LARGE_BUF_MAX_SIZE
set to 65536, we can allocate at most
4095 16-byte SCSI UNMAP block descriptors.
A single descriptor can UNMAP up to 4GB.
That gives us a hard limit of ~16 terabytes
of data that can be unmmapped by a single
request.
The same limit is also enforced by the
SCSI standard, as the entire UNMAP request
length must be smaller than 65536.
Change-Id: I4d91fa60fd28133a058b87e88a1a14ce662a659a
Signed-off-by: Dariusz Stojaczyk <dariuszx.stojaczyk@intel.com>
Reviewed-on: https://review.gerrithub.io/381447
Tested-by: SPDK Automated Test System <sys_sgsw@intel.com>
Reviewed-by: Jim Harris <james.r.harris@intel.com>
Reviewed-by: Daniel Verkamp <daniel.verkamp@intel.com>
356a9bc7d3