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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
commit76cb841cb886eef6b3bee341a2266c76578724ad (patch)
treef5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /fs/jffs2/TODO
parentInitial commit. (diff)
downloadlinux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz
linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip
Adding upstream version 4.19.249.upstream/4.19.249
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'fs/jffs2/TODO')
-rw-r--r--fs/jffs2/TODO37
1 files changed, 37 insertions, 0 deletions
diff --git a/fs/jffs2/TODO b/fs/jffs2/TODO
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+
+ - 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
+ - checkpointing (do we need this? scan is quite fast)
+ - make the scan code populate real inodes so read_inode just after
+ mount doesn't have to read the flash twice for large files.
+ Make this a per-inode option, changeable with chattr, so you can
+ decide which inodes should be in-core immediately after mount.
+ - test, test, test
+
+ - NAND flash support:
+ - almost done :)
+ - use bad block check instead of the hardwired byte check
+
+ - Optimisations:
+ - 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().
+ - Doubly-linked next_in_ino list to allow us to free obsoleted raw_node_refs immediately?
+ - 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.