\input{configpres} \subsection{Memory Technology Devices (MTD)} \title{\lq Memory Technology Devices (MTD)\rq} \maketitle \begin{frame} \tableofcontents \end{frame} \subsubsection{Overview} \begin{frame} \frametitle{Overview} \begin{itemize} \item designed for flash devices (NAND, NOR, DataFlash, OneNAND, \dots) \pause \item software- and hardware-ECC support \pause \item takes care on deletion of specified eraseblocksizes \pause \item wiring of chip is not relevant (Localbus, SPI, \dots) \end{itemize} \end{frame} \begin{frame} \frametitle{None MTD Flash Devices} \begin{itemize} \item USB sticks, CompactFlash Cards, SD Cards, SSD\dots \pause \item devices have NAND flash, but own flashcontroller \pause \item kernel handles them as block device, like a regular HDD \pause \item flash properties, like eraseblocksize, are hidden by flashcontroller \end{itemize} \end{frame} \subsubsection{MTD Kernelsubsystem} \begin{frame} \frametitle{responsibility of the MTD subsystem} \begin{itemize} \item definition of a userspace interface \pause \item partitioning of mtd devices (mtd0, mtd1, \dots) \pause \item hides flash internals from user \end{itemize} \end{frame} \begin{frame} \frametitle{NOT part of the MTD subsystem} \begin{itemize} \item filesystems \pause \item wear-leveling \pause \item protection of writing to bad blocks \pause \item data protection for writes during power loss \end{itemize} \end{frame} \begin{frame} \frametitle{mtdblock} \begin{itemize} \item enable use of common filesystem on flash devices \pause \item bad idea: no wear-leveling, bad performance, \dots \pause \item obsoleted by UBI \end{itemize} \end{frame} \input{tailpres}