X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=fs%2Fjffs2%2FTODO;fp=fs%2Fjffs2%2FTODO;h=d0e23b26fa505a0c47a8a2e09cfef039016fc8fc;hb=43bc926fffd92024b46cafaf7350d669ba9ca884;hp=2bff82fd221f7095aa691305382a21b2f346a79e;hpb=cee37fe97739d85991964371c1f3a745c00dd236;p=linux-2.6.git diff --git a/fs/jffs2/TODO b/fs/jffs2/TODO index 2bff82fd2..d0e23b26f 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.