> > 2. Turn RPMB and other ioctl() MMC operations into mmc_queue_req > things and funnel them into the block scheduler > using REQ_OP_DRV_IN/OUT requests. >
Accessing the RPMB is done via a strange protocol, in which each access is comprised of several requests. For example, writing to the RPMB will require sending 5 different requests: 2 requests to read the write counter, and then 3 more requests for the write operation itself. Once the sequence has started, it should not get interfered by other requests, or the operation will fail. So, if you are looking to eliminate the host lock, and count merely on the blk queue to regulate access to the device, You'll be needing some barrier mechanism that will assure that a sequence of requests will take place as an atomic unit. But then again, isn't it contradicts the very idea of a multi-queue? Cheers, Avri
