From 733802d974e5af42acb7cd61b16c0ce6dd03b7ed Mon Sep 17 00:00:00 2001 From: "Artem B. Bityutskiy" Date: Thu, 22 Sep 2005 12:25:00 +0100 Subject: [JFFS2] Debug code simplification, update TODO Simplify the debugging code further. Update the TODO list Signed-off-by: Artem B. Bityutskiy Signed-off-by: Thomas Gleixner --- fs/jffs2/TODO | 38 +++++++++++++++++++------------------- 1 file changed, 19 insertions(+), 19 deletions(-) (limited to 'fs/jffs2/TODO') diff --git a/fs/jffs2/TODO b/fs/jffs2/TODO index 2bff82f..d0e23b2 100644 --- a/fs/jffs2/TODO +++ b/fs/jffs2/TODO @@ -1,5 +1,11 @@ -$Id: TODO,v 1.10 2002/09/09 16:31:21 dwmw2 Exp $ +$Id: TODO,v 1.18 2005/09/22 11:24:56 dedekind Exp $ + - support asynchronous operation -- add a per-fs 'reserved_space' count, + let each outstanding write reserve the _maximum_ amount of physical + space it could take. Let GC flush the outstanding writes because the + reservations will necessarily be pessimistic. With this we could even + do shared writable mmap, if we can have a fs hook for do_wp_page() to + make the reservation. - disable compression in commit_write()? - fine-tune the allocation / GC thresholds - chattr support - turning on/off and tuning compression per-inode @@ -11,26 +17,15 @@ $Id: TODO,v 1.10 2002/09/09 16:31:21 dwmw2 Exp $ - test, test, test - NAND flash support: - - flush_wbuf using GC to fill it, don't just pad. - - Deal with write errors. Data don't get lost - we just have to write - the affected node(s) out again somewhere else. - - make fsync flush only if actually required - - make sys_sync() work. - - reboot notifier - - timed flush of old wbuf - - fix magical second arg of jffs2_flush_wbuf(). Split into two or more functions instead. - + - almost done :) + - use bad block check instead of the hardwired byte check - Optimisations: - - Stop GC from decompressing and immediately recompressing nodes which could - just be copied intact. (We now keep track of REF_PRISTINE flag. Easy now.) - - Furthermore, in the case where it could be copied intact we don't even need - to call iget() for it -- if we use (raw_node_raw->flash_offset & 2) as a flag - to show a node can be copied intact and it's _not_ in icache, we could just do - it, fix up the next_in_ino list and move on. We would need a way to find out - _whether_ it's in icache though -- if it's in icache we also need to do the - fragment lists, etc. P'raps a flag or pointer in the jffs2_inode_cache could - help. (We have half of this now.) + - Split writes so they go to two separate blocks rather than just c->nextblock. + By writing _new_ nodes to one block, and garbage-collected REF_PRISTINE + nodes to a different one, we can separate clean nodes from those which + are likely to become dirty, and end up with blocks which are each far + closer to 100% or 0% clean, hence speeding up later GC progress dramatically. - Stop keeping name in-core with struct jffs2_full_dirent. If we keep the hash in the full dirent, we only need to go to the flash in lookup() when we think we've got a match, and in readdir(). @@ -38,3 +33,8 @@ $Id: TODO,v 1.10 2002/09/09 16:31:21 dwmw2 Exp $ - Remove totlen from jffs2_raw_node_ref? Need to have totlen passed into jffs2_mark_node_obsolete(). Can all callers work it out? - Remove size from jffs2_raw_node_frag. + +dedekind: +1. __jffs2_flush_wbuf() has a strange 'pad' parameter. Eliminate. +2. get_sb()->build_fs()->scan() path... Why get_sb() removes scan()'s crap in + case of failure? scan() does not clean everything. Fix. -- cgit v1.1