This fixes issue #1224 - null pointer dereference in kernel in the IO path with large IO's issued
Signed-off-by: Krzysztof Majzerowicz-Jaszcz <krzysztof.majzerowicz-jaszcz@intel.com>
OCF cannot allocate request map bigger than 4MiB (due to kmalloc
limitations), thus we need to split bigger IOs into series smaller
ones to reduce request map size.
Signed-off-by: Robert Baldyga <robert.baldyga@intel.com>