Jump to content











Photo

CDFS partition on HDD/SSD


  • Please log in to reply
5 replies to this topic

#1 Alexander Ceed

Alexander Ceed

    Frequent Member

  • Advanced user
  • 207 posts

Posted 02 May 2016 - 09:26 AM

I have an USB drive that uses a SSD controller which appears as a fixed drive. I'd like to try to create a CDFS partition on it. The exact controller make/model is not being detected by ChipGenius and ChipEasy doesn't display anything helpful either.  The drive in question is a Corsair Flash Voyager GTX 256GB USB 3.0.

But I'd also like to know how to do this on internal HDDs/SSDs.

 

Searched the web but could not find anything conclusive.

Thank you and happy holidays!

 



#2 Wonko the Sane

Wonko the Sane

    The Finder

  • Advanced user
  • 13745 posts
  • Location:The Outside of the Asylum (gate is closed)
  •  
    Italy

Posted 02 May 2016 - 10:37 AM

I have an USB drive that uses a SSD controller which appears as a fixed drive. I'd like to try to create a CDFS partition on it. The exact controller make/model is not being detected by ChipGenius and ChipEasy doesn't display anything helpful either.  The drive in question is a Corsair Flash Voyager GTX 256GB USB 3.0.

But I'd also like to know how to do this on internal HDDs/SSDs.

 

Searched the web but could not find anything conclusive.

Thank you and happy holidays!

It greatly depends on WHAT you wish this for and WHICH OS you intend to use and more generally if the firmware doesn't support it or you can't access the firmware it will be anyway a "hack" with a few strings attached.

 

Some USB sticks have a controller that can be set as having two LUN's, i.e. the controller exposes two devices, one being a CD/DVD-like one and the other being a Hard Disk-like one.

 

This is not the case for those (like yours, presumably) that have a USB-to-Sata bridge and a "normal" SATA SSD inside.

 

It even *seems* like some of those "high speed" sticks are programmed through an internal BUS in factory (before being enclosed in the case), not through the USB interface.

 

You can have a partition in the MBR that actually represents a ISO image (which can be CDFS or UDF) but that volume will normally be NOT accessible by Windows NT based systems (while there would be  *no* issues  in *any* Linux).

 

Such a partition may be bootable (as an example through grub4dos), but again it may depend on the OS booted and how exactly it is booted.

 

The trick is widely used in Easy2boot for some Linux distro's/LiveCD's that have issues in being booted as "simple" images, the origin is here:
http://reboot.pro/to...ge-2#entry88531

 

In Windows such a partition can be mounted using a third party driver, such as Winvblock/Firadisk or IMDISK, with a few tricks.

 

The "CDFS partition" can be of course used also on hard disks or "internal" SSD's, but please understand the differences involved, in the case of the two LUN's device the CDFS is very like a CD, i.e. the media is Read Only (unless you use specifically the Mass Production Tool), while in the case of a partition, it is more like a CDRW, i.e. a number of "normal" tools can change or wipe its contents.

 

:duff:

Wonko

 

P.S.: BTW and slightly off-topic, whilst it is improbable that newish Windows version support "natively" CDFS on hard disk-like device, "native" support for UDF might be available.



#3 Alexander Ceed

Alexander Ceed

    Frequent Member

  • Advanced user
  • 207 posts

Posted 02 May 2016 - 11:48 AM

The "CDFS partition" can be of course used also on hard disks or "internal" SSD's, but please understand the differences involved, in the case of the two LUN's device the CDFS is very like a CD, i.e. the media is Read Only (unless you use specifically the Mass Production Tool), while in the case of a partition, it is more like a CDRW, i.e. a number of "normal" tools can change or wipe its contents.

 

For now, I'm just interested in the autorun functionality. Not trying to boot off it and there's no problem if it's writable.

 

 

P.S.: BTW and slightly off-topic, whilst it is improbable that newish Windows version support "natively" CDFS on hard disk-like device, "native" support for UDF might be available.

 

So you are saying, a partition in MBR with UDF filesystem is visible to windows? And one in CDFS will not be visible?



#4 Wonko the Sane

Wonko the Sane

    The Finder

  • Advanced user
  • 13745 posts
  • Location:The Outside of the Asylum (gate is closed)
  •  
    Italy

Posted 02 May 2016 - 06:13 PM

 

So you are saying, a partition in MBR with UDF filesystem is visible to windows? And one in CDFS will not be visible?

More or less yes (though it needs to be tested/verified).

 

Starting with (cannot remember if Vista or 7) the Format.com allows to use the UDF filesystem, see:
http://superuser.com...df-in-windows-7

the partition ID for the UDF formatted partition should be still either 07 (like NTFS or exFAT) or 06 (like FAT16):
http://serverfault.c...em-type-for-udf

so *somehow* there must be a filesystem recognizer that "connects" the UFDS.SYS (the UDF file system driver) to the partition/volume, while I believe there is not the same mechanism for CDFS.SYS (CDFS file system driver).

 

:duff:

Wonko



#5 Alexander Ceed

Alexander Ceed

    Frequent Member

  • Advanced user
  • 207 posts

Posted 02 May 2016 - 10:27 PM

I created a partition as extFAT, then used format H: /fs:UDF /q to format as UDF. Partition is seen, writable, but since it is seen as a normal drive, autorun.inf won't start.

What about CDFS filesystem? Is there a way to format as CDFS or do I need create the partition as CDFS? How can this be done?



#6 Wonko the Sane

Wonko the Sane

    The Finder

  • Advanced user
  • 13745 posts
  • Location:The Outside of the Asylum (gate is closed)
  •  
    Italy

Posted 03 May 2016 - 07:00 AM

I created a partition as extFAT, then used format H: /fs:UDF /q to format as UDF. Partition is seen, writable, but since it is seen as a normal drive, autorun.inf won't start.

What about CDFS filesystem? Is there a way to format as CDFS or do I need create the partition as CDFS? How can this be done?

You cannot create a CDFS partition with "normal" tools.

You create a .iso, dd-copy it to an (unused) extent (contiguous) on the disk, then create a partition entry for it.

In any case I doubt that autorun.inf will work from it, as a matter of fact you won't be able to mount/access it unless you use a dedicated driver in Windows.

 

:duff:

Wonko






0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users