Instead of using two members for maintaining the state of a VHM request, this
patch replaces the transitions with a single state. Basically the lifecycle of a
VHM request shall be:
FREE -> PENDING -> PROCESSING -> COMPLETE -> FREE -> ...
The structure header of vhm_request has more details of the transitions access
limitations under different states.
Also drop the set but unused member vcpu.ioreq_pending.
For backward-compatibility, the obsolete 'valid' member is still kept and
maintained before SOS and DM adapts to the new state transitions.
v2 -> v3:
* Use complete_ioreq to mark an I/O request finished in
dm_emulate_(pio|mmio)_post.
Signed-off-by: Junjie Mao <junjie.mao@intel.com>
Acked-by: Eddie Dong <eddie.dong@intel.com>
17771c0ac2