mtd/fs/jffs3 JFFS3design.tex,1.28,1.29

[Artem Bityuckiy]

Update of /home/cvs/mtd/fs/jffs3
In directory phoenix.infradead.org:/tmp/cvs-serv26824

Modified Files:
	JFFS3design.tex 
Log Message:
Add the new "Virtual block handling" section written by tglx1.



Index: JFFS3design.tex
===================================================================
RCS file: /home/cvs/mtd/fs/jffs3/JFFS3design.tex,v
retrieving revision 1.28
retrieving revision 1.29
diff -u -r1.28 -r1.29
--- JFFS3design.tex	25 Mar 2005 17:45:31 -0000	1.28
+++ JFFS3design.tex	26 Mar 2005 11:55:01 -0000	1.29
@@ -20,7 +20,7 @@
 %  TITLE PAGE
 %
 \title{JFFS3 design issues}
-\author{Artem B. Bityuckiy}
+\author{Artem B. Bityuckiy, Thomas Gleixner}
 \maketitle
 
 %
@@ -64,8 +64,8 @@
 block has been erased.
 \end{itemize}
 
-Different flash technologies imply different reliability. The following is the
-brief overview of Flash technologies in this perspective.
+Different flash technologies imply different reliability. The following
+is a brief overview of Flash technologies in this perspective.
 
 \begin{itemize}
 \item \emph{NOR}
@@ -184,6 +184,20 @@
 generate redundant adler32 checksum for better performance.
 
 %
+% VIRTUAL BLOCK HANDLING
+%
+\section{Virtual Block handling}
+The concatenation of blocks to virtual blocks must deal with
+bad blocks in the virtual block rather than treating the
+whole virtual block as bad (as it is done in JFFS2).
+Therefore JFFS3 must treat the blocks inside a virtual block seperately.
+This implies the clean marker write per physical block after erase and
+the limitation of writes to physical block boundaries.
+
+A nice benefit is that this keeps the File System compatible for different
+concatenation settings in case of removable media.
+
+%
 % MAXIMAL SIZE OF THE INODE NODE DATA
 %
 \section{Maximal size of the inode node data}
@@ -490,7 +504,7 @@
 \item \emph{Non-pristine node} -- a type of data node which contains the amount
 of uncompressed data which is not multiple of \texttt{PAGE\_SIZE} bytes.
 
-i\item \emph{ICP entry} - a short record in ICP referring a node.
+\item \emph{ICP entry} - a short record in ICP referring a node.
 
 \item \emph{Icp\_ref} - a small object representing an ICP. Belongs to
 the in-core objects group.