UDF file system server

1 Current status

FS type	Reading	Writing
UDF Plain	±	-
DVD Video	+	N/A
Blu-Ray Video	-	N/A

2 TODO plan

• Complete reading UDF plain disks
• Complete and test reading Blu-ray disks
• Complete support big-endian archs
• Implement initial writing support for UDF plain disks

3 How to test

3.1 Download sources from my branch

bzr branch lp:~medvedeva-julia/helenos/udf helenos

3.2 Compile sources

cd helenos
make PROFILE=ia32

3.3 Create UDF disk image under Linux

To create UDF image under Linux you need to install package with ​UDF utilities. For example in Arch it's ​udftools. The package should contain the mkudffs tool.

mkudffs --media-type=hd --blocksize=512 --utf8 ./udf.img

You can also select media type: "hd" or "dvd" and blocksize: 512 or 2048 or something else.

Unless you are overwriting already existing image, you need to create an empty file first (otherwise you would get the trying to change type of multiple extents error). Following creates a 32M file:

dd if=/dev/zero of=./udf.img bs=4096 count=8192

3.4 Mount udf disk image under Linux

You can mount the UDF image (from step 3.3) under your Linux host and copy several files into it.

mount -o loop -t udf ./udf.img /mnt/udf-mount-point

where udf.img is the image from step 3.3

3.5 Boot HelenOS with user disk image

To boot HelenOS run QEMU:

qemu-system-i386 -m 512 -boot d -hda udf.img -cdrom image.iso

udf.img is the UDF disk image

3.6 Mount user disk image under HelenOS

In HelenOS run a batch script to run UDF server, ATA server and mount the first ATA disk as UDF.

batch u

Then, go to the /mnt directory:

cd /mnt

and here you are

4 Read functions dashboard

VFS method	Task	Implementation	File	Progress	TODO and comments
mounted	check volume recognition sequence	udf_volume_recongnition	udf_volume	done
	search for anchor volume descriptor	udf_get_anchor_volume_descriptor	udf_volume	done
	read volume descriptor sequence	udf_read_volume_descriptor_sequence	udf_volume	done
	data structure for saving information about item (file or dir)	udf_node_t	udf.h	done
	hash table for udf_node saving	udf_idx_	udf_idx	done	udf_idx_hash too simple
	ckecksum functions	entire file	udf_cksum	done
	osta unicode compression	entire file	udf_osta	done
	mount udf disk	udf_mounted	udf_ops	done