scsi: ufs: ufshpb: L2P map management for HPB read
Implement L2P map management in HPB. The HPB divides logical addresses into several regions. A region consists of several sub-regions. The sub-region is a basic unit where L2P mapping is managed. The driver loads L2P mapping data of each sub-region. The loaded sub-region is called active-state. The HPB driver unloads L2P mapping data as region unit. The unloaded region is called inactive-state. Sub-region/region candidates to be loaded and unloaded are delivered from the UFS device. The UFS device delivers the recommended active sub-region and inactivate region to the driver using sense data. The HPB module performs L2P mapping management on the host through the delivered information. A pinned region is a preset region on the UFS device that is always in activate-state. The data structures for map data requests and L2P mappings use the mempool API, minimizing allocation overhead while avoiding static allocation. The mininum size of the memory pool used in the HPB is implemented as a module parameter so that it can be configurable by the user. To guarantee a minimum memory pool size of 4MB: ufshpb_host_map_kbytes=4096. The map_work manages active/inactive via 2 "to-do" lists: - hpb->lh_inact_rgn: regions to be inactivated - hpb->lh_act_srgn: subregions to be activated These lists are maintained on I/O completion. [mkp: switch to REQ_OP_DRV_*] Link: https://lore.kernel.org/r/20210712085859epcms2p36e420f19564f6cd0c4a45d54949619eb@epcms2p3 Tested-by:Bean Huo <beanhuo@micron.com> Tested-by: