Re: [PATCH v2 0/4] rpmb subsystem, uapi and virtio-rpmb driver

[Bean Huo]

On Wed, 2022-04-06 at 10:32 -0700, Bart Van Assche wrote:
> > It's the SCSI BSG driver, in fact, we don't have a dedicated UFS
> > RPMB
> > driver in the kernel. RPMB is a well known LU, we are using
> > userspace
> > tools to issue SCSI commands directly to the UFS RPMB LU via
> > ioctl()
> > from the BSG device node in the /dev/sg/ folder.
> > 
> > Here is the BSG part of the code in the userspace tools:
> > 
> >           io_hdr_v4.guard = 'Q';
> >           io_hdr_v4.protocol = BSG_PROTOCOL_SCSI;
> >           io_hdr_v4.subprotocol = BSG_SUB_PROTOCOL_SCSI_CMD;
> >           io_hdr_v4.response = (__u64)sense_buffer;
> >           io_hdr_v4.max_response_len = SENSE_BUFF_LEN;
> >           io_hdr_v4.request_len = cmd_len;
> >           io_hdr_v4.request = (__u64)cdb;
> >                                                                    
> >                                                          
> >                                                                    
> >                 
> >           ioctl(fd, SG_IO, &io_hdr_v4))
> 
> Hi Bean,
> 
> I'm not sure where the above comes from? The Android RPMB client uses
> slightly different code. Additionally, the retry loop around the 
> submission of SG/IO commands is very important. See also the 
> check_sg_io_hdr() call in send_ufs_rpmb_req(). See also 
> https://cs.android.com/android/platform/superproject/+/master:system/core/trusty/storage/proxy/rpmb.c
> 
> 
Bart,

It is from the ufs-utils.

So, do you vote to add the UFS RPMB driver based on this new framework
to resolve this conflict?


Kind regards,
Bean

> Thanks,
> 


> Bart.