mtd/fs/jffs3 JFFS3design.tex,1.14,1.15

[Artem Bityuckiy]

Update of /home/cvs/mtd/fs/jffs3
In directory phoenix.infradead.org:/tmp/cvs-serv5983

Modified Files:
	JFFS3design.tex 
Log Message:
Add few more definitions. Change text layout on paper.


Index: JFFS3design.tex
===================================================================
RCS file: /home/cvs/mtd/fs/jffs3/JFFS3design.tex,v
retrieving revision 1.14
retrieving revision 1.15
diff -u -r1.14 -r1.15
--- JFFS3design.tex	29 Jan 2005 11:42:28 -0000	1.14
+++ JFFS3design.tex	3 Feb 2005 15:09:40 -0000	1.15
@@ -6,11 +6,14 @@
 % $Id$
 %
 
-\documentclass[12pt,a4paper,twoside,titlepage]{article}
+\documentclass[12pt,a4paper,oneside,titlepage]{article}
 \usepackage{longtable}
 \usepackage{hyperref}
 \usepackage{html}
-\sloppy
+\textwidth=18cm
+\oddsidemargin=0cm
+\topmargin=0cm
+\textheight=24cm
 
 \begin{document}
 
@@ -47,7 +50,7 @@
 % ABBREVIATIONS
 %
 \section{Abbreviations}
-\begin{longtable}{p{3cm}p{11cm}}
+\begin{longtable}{p{3cm}p{14.5cm}}
 \large \textbf{Abbrev.} & \large \textbf{Definition} \\[7pt]
 
 \emph{CRC} & Cyclic Redurancy Check \\[4pt]
@@ -58,6 +61,8 @@
 
 \emph{MTD} & Memory Technology Device \\[4pt]
 
+\emph{ICP} & Inode Check-Point \\[4pt]
+
 \end{longtable}
 
 %
@@ -65,7 +70,7 @@
 %
 \section{Definitions}
 
-\begin{longtable}{p{3cm}p{11cm}}
+\begin{longtable}{p{3cm}p{14.5cm}}
 
 \large \textbf{Term} & \large \textbf{Definition}
 \\[7pt]
@@ -80,6 +85,16 @@
 details.
 \\[4pt]
 
+\raggedright \emph{In-core memory}
+&
+The memory that is always consumed by JFFS3 irrespective on are there opened files
+or not. This memory can not be reaped by the Linux VM subsystem and the only way
+to reclaim it is to unmount the JFFS3 fylesystem.
+The in-core memory which is consumed by JFFS3 depends lineary on
+the number of inodes (TODO: take care, not designed yet) on the flash.
+TODO:  list the in-core objects data types here.
+\\[4pt]
+
 \raggedright \emph{Block, Sector}
 &
 The minimal flash erasable unit.
@@ -134,19 +149,34 @@
 \texttt{struct~jffs3\_raw\_inode} objects.
 \\[4pt]
 
-\raggedright \emph{Direntry node}
+\raggedright \emph{Direntry node, direntry}
 &
 Each JFFS3 directory entry is represented by the direntry node.
 Direntry nodes are \texttt{struct~jffs3\_raw\_dirent} objects.
 \\[4pt]
 
-\raggedright \emph{Summary node}
+\raggedright \emph{Summary node, summary}
 &
 Summary node is special node type which describes the layout of
 not-empty eblocks. Summary blocks are situated at the end of each eblock
 (which contain some data) and describe the position, type, length and
 some other parameters of all the eblock's nodes. Summary nodes are
 \texttt{struct~jffs3\_raw\_summary} objects.
+
+Summary nodes are used to quickly get the information about
+the block physical layout.
+\\[4pt]
+
+\raggedright \emph{Inode checkpoint node, ICP, checkpoint}
+&
+Inode checkpoint node, or ICP node, or just checkpoint is the kind of JFFS3
+node. ICP relates to some inode and there may be several ICPs corresponding to
+one inode. ICP describes the nodes of the inode and is used to quickly aquire
+the information about an inode's nodes. Checkpoints are similar to summaries,
+but contain the per-inode information rather then per-block. ICPs are
+\texttt{struct~jffs3\_raw\_icp} objects.
+
+ICP nodes are used to quickly aquire the information about the inode's nodes.
 \\[4pt]
 
 \raggedright \emph{Summary end magic bitmask}
@@ -298,6 +328,13 @@
 JFFS2 uses the CRC32 algoritm with the start seed 0.
 
 %
+% MEMORY CONSUMPTION
+%
+\section{Memory consumption}
+\subsection{JFFS2 and memory consumption}
+TODO: describe JFFS2 problems
+
+%
 % MISCELLANIOUS
 %
 \section{Miscellanious}
@@ -367,11 +404,11 @@
 
 \item \raggedright \label{ref_GormanVM}
 Mel Gorman, Linux VM Documentation,\\
-\url{www.csn.ul.ie/~mel/projects/vm}
+\url{www.csn.ul.ie/~mel/projects/vm}.
 
 \item \raggedright \label{ref_ToshibaNAND}
 Toshiba NAND Flash Applications Design Guide,\\
-www.semicon.toshiba.co.jp/eng/prd/memory/doc/pdf/\\nand\_applicationguide\_e.pdf
+\url{www.semicon.toshiba.co.jp/eng/prd/memory/doc/pdf/nand\_applicationguide\_e.pdf}.
 \end{enumerate}
 
 \end{document}