\def\lximg{/usr/share/lx/icons/fueller.png}

\input{configpres}

\subsection{Creating Flashfilesystems}

\title{Creating Flashfilesystems}
\maketitle

\def\lximg{none}

\begin{frame}
\frametitle{Contents}
\tableofcontents
\end{frame}

\subsubsection{Emulation}
\begin{frame}[fragile]
\frametitle{Emulating flash devices}
Exercise:
\begin{lstlisting}
$ sudo modprobe nandsim
$ cat /proc/mtd 
dev:    size   erasesize  name
mtd0: 08000000 00004000 "NAND simulator partition 0"
$ dmesg
[...]
[  128.718421] flash size: 128 MiB
[  128.718423] page size: 512 bytes
[  128.718425] OOB area size: 16 bytes
[  128.718426] sector size: 16 KiB
[...]
\end{lstlisting}
\end{frame}

\subsubsection{JFFS2}
\begin{frame}[fragile]
\frametitle{MTD Flash partitioning}
\begin{itemize}
\item Redboot partition parsing
\item Boardsupport
\item Kernelparameters:
\begin{verbatim}
mtdparts=edb7312-nor:256k(ARMboot)ro,
-(root);edb7312-nand:-(home)
\end{verbatim}
\end{itemize}
\end{frame}

\begin{frame}
\frametitle{JFFS2}
\begin{figure}[h]
\centering
\includegraphics[width=8cm]{images/jffs2.png}
\end{figure}
\end{frame}

\begin{frame}[fragile]
\frametitle{Using JFFS2}
Exercise:
\begin{lstlisting}
# Create JFFS2 image
$ /usr/sbin/mkfs.jffs2 -e 131072 \
             -d source_directory \
             -o jffs2.img
# Erase flash partition
$ sudo flash_erase -j /dev/mtd0 0 0
# Write jffs2 image
$ sudo nandwrite -p /dev/mtd0 jffs2.img
# Load mtdblock module
$ sudo modprobe mtdblock
# Mounting the image
$ sudo mount -t jffs2 /dev/mtdblock0 /mnt
\end{lstlisting}
Clean-up:
\begin{lstlisting}
# Unmount the image and erase flash partition
$ sudo umount /mnt
$ sudo flash_erase -j /dev/mtd0 0 0
\end{lstlisting}
\end{frame}

\begin{frame}[fragile]
Kernelparameters:
\begin{verbatim}
root=/dev/mtdblock0 rootfstype=jffs2
\end{verbatim}
\end{frame}

\subsubsection{UBI and UBIFS}
\begin{frame}
\frametitle{UBI: Unsorted Block Images}
\begin{figure}[h]
\centering
\includegraphics[width=8cm]{images/ubi.png}
\end{figure}
\end{frame}

\begin{frame}
\frametitle{UBIFS}
\begin{figure}[h]
\centering
\includegraphics[width=8cm]{images/ubifs.png}
\end{figure}
\end{frame}

\begin{frame}[fragile]
\frametitle{Using UBIFS}
Exercise:
\begin{lstlisting}
# 1) Loading module and attach UBI to MTD device
$ sudo modprobe ubi
$ sudo ubiattach ubiattach -m 0
# or: 1a) Specify the MTD device during module load
$ sudo modprobe ubi mtd=0
# 2) Gathering some information:
$ dmesg
UBI: attaching mtd0 to ubi0
UBI: physical eraseblock size:   16384 bytes (16 KiB)
UBI: logical eraseblock size:    15872 bytes
UBI: smallest flash I/O unit:    512
UBI: sub-page size:              256
UBI: VID header offset:          256 (aligned 256)
UBI: data offset:                512
[...]
# 3) Creating an UBIFS image
$ /usr/sbin/mkfs.ubifs -r test -m 512 -e 15872 \
              -c 8450 -o ubifs.img
\end{lstlisting}
\end{frame}

\begin{frame}[fragile]
\frametitle{Using UBIFS}
Exercise (cont.):
\begin{lstlisting}
# 4) Creating a volume
$ sudo ubimkvol /dev/ubi0 -N myvolume -s 64MiB
# 5) Writing the image
$ sudo ubiupdatevol /dev/ubi0_0 ubifs.img
# 6) Mounting UBIFS
$ sudo mount -t ubifs ubi0:myvolume /mnt/
\end{lstlisting}
Clean-up:
\begin{lstlisting}
# Unmounting image, detach UBI from MTD device, and erase flash partition
$ sudo umount /mnt
$ sudo ubidetach -m 0
$ sudo flash_erase -j /dev/mtd0 0 0
\end{lstlisting}
\end{frame}

\begin{frame}[fragile]
\frametitle{UBI: Create flash images}
ubinize.cfg:
\begin{verbatim}
[ubifs]
mode=ubi
image=ubifs.img
vol_id=0
vol_size=64MiB
vol_type=dynamic
vol_name=myvolume
vol_flags=autoresize
\end{verbatim}
\end{frame}

\begin{frame}[fragile]
\frametitle{UBI: Create flash images}
Exercise:
\begin{lstlisting}
# 1) Create the ubi image
$ /usr/sbin/ubinize -o ubi.img -m 512 -s 256 -p 16384 ubinize.cfg
# 2) Write the image
$ sudo nandwrite /dev/mtd0 ubi.img
# 3) Attach UBI
$ sudo ubiattach -m 0
# 4) Mount UBIFS
$ sudo mount -t ubifs ubi0:myvolume /mnt/
\end{lstlisting}
Clean-up:
\begin{lstlisting}
# Unmounting image, detach UBI from MTD device, and erase flash partition
$ sudo umount /mnt
$ sudo ubidetach -m 0
$ sudo flash_erase -j /dev/mtd0 0 0
\end{lstlisting}
\end{frame}

\begin{frame}[fragile]
\frametitle{UBIFS as a rootfilesystem}
Kernelparameters:
\begin{verbatim}
ubi.mtd=0 root=ubi0:myvolume rootfstype=ubifs
\end{verbatim}
\end{frame}

\subsection{}
\begin{frame}
\frametitle{References}
\begin{thebibliography}{1}
\bibitem{UBIFS} http://mytechrants.wordpress.com/2010/01/20/ubiubifs-on-nandsim/
\end{thebibliography} 
\end{frame}

\input{tailpres}