For I/O that do not span a cluster boundary, just issue
a single batch command to underlying block device.
For I/O that do span a cluster boundary, issue a batch
command for each against the blob (not the block device)
for each cluster accessed by the I/O.
This is all in preparation for upcoming patches which
enable thin provisioning and hence cluster allocation
in the I/O path. It will simplify implementation of
the cluster allocation path since now that code only
needs to be concerned with a single allocation at once.
Splitting for readv/writev will be handled in a
later patch.
Signed-off-by: Jim Harris <james.r.harris@intel.com>
Change-Id: Ia2341abbda599dace3357c4eec06ab6602ef81a8
Reviewed-on: https://review.gerrithub.io/395027
Tested-by: SPDK Automated Test System <sys_sgsw@intel.com>
Reviewed-by: Ben Walker <benjamin.walker@intel.com>
Reviewed-by: Maciej Szwed <maciej.szwed@intel.com>
Reviewed-by: Tomasz Zawadzki <tomasz.zawadzki@intel.com>
Reviewed-by: Daniel Verkamp <daniel.verkamp@intel.com>