isci: unify can_queue tracking on the tci_pool, uplevel tag assignment
The tci_pool tracks our outstanding command slots which are also the 'index'
portion of our tags. Grabbing the tag early in ->lldd_execute_task let's us
drop the isci_host_can_queue() and ->was_tag_assigned_by_user infrastructure.
->was_tag_assigned_by_user required the task context to be duplicated in
request-local buffer. With the tci established early we can build the
task_context directly into its final location and skip a memcpy.
With the task context buffer at a known address at request construction we
have the opportunity/obligation to also fix sgl handling. This rework feels
like it belongs in another patch but the sgl handling and task_context are too
intertwined.
1/ fix the 'ab' pair embedded in the task context to point to the 'cd' pair in
the task context (previously we were prematurely linking to the staging
buffer).
2/ fix the broken iteration of pio sgls that assumes all sgls are relative to
the request, and does a dangerous looking reverse lookup of physical
address to virtual address.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
7 files changed