CA-160092: Import missing hunk from commit 4be47e0b
CA-160092: Import missing hunk from commit 4be47e0b

This import is necessary to be able to disable read-caching.

Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com>
Reviewed-by: Thanos Makatos <thanos.makatos@citrix.com>

[siddharthv imported missing hunk in the 'open' method]
Signed-off-by: Siddharth Vinothkumar <siddharth.vinothkumar@citrix.com>
Reviewed-by: Thanos Makatos <thanos.makatos@citrix.com>
Acked-by: Germano Percossi <germano.percossi.citrix.com>

GitHub: closes #243 on xapi-project/sm

geosharath/sm,chandrikas/sm,martinjorge/sm,pritha-srivastava/sm,geosharath/sm,xapi-project/sm,malcolmcrossley/sm,chandrikas/sm,robertbreker/sm,xapi-project/sm,malcolmcrossley/sm,djs55/sm,malcolmcrossley/sm,robertbreker/sm,kostaslamda/sm,kostaslamda/sm,germanop/sm,martinjorge/sm,germanop/sm,chandrikas/sm,germanop/sm,robertbreker/sm,djs55/sm,martinjorge/sm,xapi-project/sm,geosharath/sm,pritha-srivastava/sm,djs55/sm,pritha-srivastava/sm,kostaslamda/sm