UFS utilities

UFS utilities

[Bean Huo (beanhuo)]

Hi, all 
Is there someone knows if exists one utilis dedicated to UFS device, rather than SCSI utils?
I have tried sg3-utils, but it is not convenient for the embedded ARM-based system.
And also it doesn't support several UFS special command. 
If we don't have this kind of tool for UFS, is it necessary for us to develop a ufs-utils?
I need your every expert's inputs and suggestions.
Thanks in advance.

//Bean Huo

Re: UFS utilities

[Greg KH]

On Mon, Nov 27, 2017 at 11:25:47AM +0000, Bean Huo (beanhuo) wrote:
> Hi, all 
> Is there someone knows if exists one utilis dedicated to UFS device, rather than SCSI utils?
> I have tried sg3-utils, but it is not convenient for the embedded ARM-based system.
> And also it doesn't support several UFS special command. 

What specific UFS commands do you need to make to the device that the
current driver does not support?

And yes, this is a trick question as there are about 4 different major
forks that I know of of the UFS driver in different vendor trees, all of
which support different types of UFS commands :(

> If we don't have this kind of tool for UFS, is it necessary for us to develop a ufs-utils?

I doubt it, what neds to happen is getting all of the functionality that
lives in these different forks all merged upstream into the in-kernel
driver.  Then I bet all of the needed functionality you are looking for
will be there.

good luck!

greg k-h

Re: UFS utilities

[Bart Van Assche]

On Mon, 2017-11-27 at 11:25 +0000, Bean Huo (beanhuo) wrote:
> Is there someone knows if exists one utilis dedicated to UFS device,
> rather than SCSI utils? I have tried sg3-utils, but it is not convenient
> for the embedded ARM-based system.

Hello Bean,

Please be more specific. What is inconvenient about sg3_utils on embedded
ARM systems?

> And also it doesn't support several UFS special command. 

Are you referring to SCSI commands or rather to UFS commands that fall
outside the SCSI spec? Anyway, an approach that is used by many SCSI drivers
to export information to user space that falls outside the SCSI spec is to
create additional sysfs attributes. See also the sdev_attrs and shost_attrs
members of struct scsi_host_template.

Bart.

RE: [EXT] Re: UFS utilities

[Bean Huo (beanhuo)]

Hi, Bart
Sorry for later!
>
>Hello Bean,
>
>Please be more specific. What is inconvenient about sg3_utils on embedded
>ARM systems?
>
Exactly, I don't know how to compile sg3_utils with static library, instead of sharing library. I used following configuration
Parameter:
./configure --enable-static=yes --build=x86_64-unknown-linux-gnu --host=aarch64-linux-gnu  --prefix=$PWD/out/  CC=aarch64-linux-gnu-g
    cc --target=aarch64-linux-gnu LD=aarch64-linux-gnu-ld AS=aarch64-linux-gnu-as CFLAGS=-static LDFLAGS=-static

But the object files are still dynamically linked.

ELF 64-bit LSB executable, ARM aarch64, version 1 (SYSV), dynamically linked, interpreter /lib/ld-linux-aarch64.so.1, 
for GNU/Linux 3.7.0, BuildID[sha1]=4f01b4c9f1ff47bc00aef93950c02734b4cc8e57, not stripped.

I want it to be statically linked. Otherwise, I should copy its library to my lib folder, and sometimes for the embedded, 
Need to re-build rootfs. Meanwhile, for the UFS, there are totally 27 scsi commands being used based on UFS2.1.
For the most case, we just use several sg3_utils object files, don't need to copy all object files to the ending product. 

>> And also it doesn't support several UFS special command.
>
>Are you referring to SCSI commands or rather to UFS commands that fall
>outside the SCSI spec? Anyway, an approach that is used by many SCSI drivers
>to export information to user space that falls outside the SCSI spec is to
>create additional sysfs attributes. See also the sdev_attrs and shost_attrs
>members of struct scsi_host_template.
>
Yes, for the UFS information, I can use these interface/approach to easily get.
I am thinking how about some testing case and configuration operation.
Also, is it possible bypass SCSI stacks and go into directly UFS stack?
Thanks for your inputs.
>Bart.

//Bean Huo

Re: [EXT] Re: UFS utilities

[gregkh]

On Mon, Dec 04, 2017 at 03:20:34PM +0000, Bean Huo (beanhuo) wrote:
> Hi, Bart
> Sorry for later!
> >
> >Hello Bean,
> >
> >Please be more specific. What is inconvenient about sg3_utils on embedded
> >ARM systems?
> >
> Exactly, I don't know how to compile sg3_utils with static library, instead of sharing library. I used following configuration
> Parameter:
> ./configure --enable-static=yes --build=x86_64-unknown-linux-gnu --host=aarch64-linux-gnu  --prefix=$PWD/out/  CC=aarch64-linux-gnu-g
>     cc --target=aarch64-linux-gnu LD=aarch64-linux-gnu-ld AS=aarch64-linux-gnu-as CFLAGS=-static LDFLAGS=-static
> 
> But the object files are still dynamically linked.
> 
> ELF 64-bit LSB executable, ARM aarch64, version 1 (SYSV), dynamically linked, interpreter /lib/ld-linux-aarch64.so.1, 
> for GNU/Linux 3.7.0, BuildID[sha1]=4f01b4c9f1ff47bc00aef93950c02734b4cc8e57, not stripped.
> 
> I want it to be statically linked. Otherwise, I should copy its library to my lib folder, and sometimes for the embedded, 
> Need to re-build rootfs. Meanwhile, for the UFS, there are totally 27 scsi commands being used based on UFS2.1.
> For the most case, we just use several sg3_utils object files, don't need to copy all object files to the ending product. 

So what UFS commands are you missing that you need to see implemented?

And again, have you checked the different forks of the driver?

> >> And also it doesn't support several UFS special command.
> >
> >Are you referring to SCSI commands or rather to UFS commands that fall
> >outside the SCSI spec? Anyway, an approach that is used by many SCSI drivers
> >to export information to user space that falls outside the SCSI spec is to
> >create additional sysfs attributes. See also the sdev_attrs and shost_attrs
> >members of struct scsi_host_template.
> >
> Yes, for the UFS information, I can use these interface/approach to easily get.
> I am thinking how about some testing case and configuration operation.

Which ones exactly?

> Also, is it possible bypass SCSI stacks and go into directly UFS stack?

Look at the different sysfs files for the UFS device, it does that for
some commands.

thanks,

greg k-h

Re: UFS utilities

[Bart Van Assche]

On Mon, 2017-12-04 at 15:20 +0000, Bean Huo (beanhuo) wrote:
> Also, is it possible bypass SCSI stacks and go into directly UFS stack?

Hello Bean,

Sorry but I think it would be wrong to bypass the block layer when submitting
UFS commands. My understanding is that UFS devices are used in systems where
power management functionality is important (see also Documentation/power).
If the block layer would be bypassed then the power management support that
exists in the block layer will have to be reimplemented in UFS devices. That
would be a duplicate effort. I'm not sure that we want such duplication.

Bart.