Updated ToDo file.

git-svn-id: file:///srv/svn/repos/haiku/trunk/current@2168 a95241bf-73f2-0310-859d-f6bbb57e9c96

src/add-ons/kernel/file_systems/bfs/ToDo

@@ -1,4 +1,4 @@
-BFS - ToDo, November 18th, 2002
+BFS - ToDo, December 6th, 2002
 -----
 
 BlockAllocator
@@ -6,7 +6,7 @@ BlockAllocator
  - the BlockAllocator is only slightly optimized and probably slow
  - the first free and the largest range are currently not correctly maintained (only efficiency suffers - it does work correctly)
  - the allocation policies will have to stand against some real world tests
- - the access to the block bitmap is currently managed using a global lock
+ - the access to the block bitmap is currently managed using a global lock (doesn't matter as long as transactions are serialized)
 
 
 DataStream
@@ -19,7 +19,7 @@ Queries
 
  - There shouldn't be any cases where you can speed up a query with reordering the query expression - test it
  - Check permissions of the parent directories
- - Add protection against crashing applications which had a query open - at least the original BeOS kernel does not free the cookie (which throws some memory away *and* prevents unmounting the disk)
+ - Add protection against crashing applications which had a query open - at least the original BeOS kernel does not free the cookie (which throws some memory away *and* prevents unmounting the disk), but that won't be needed for OpenBeOS
  - the query set for "!=" and last_modified/size is not the same as for "="; last_modified/size don't contain directories
 
 
@@ -28,7 +28,7 @@ Journal
  - Check if there are any standard and often-happening cases for a transaction to fail, and if so, start the transaction only when necessary
  - if the system crashes between bfs_unlink() and bfs_remove_vnode(), the inode can be removed from the tree, but its memory is still allocated - this can happen if the inode is still in use by someone (and that's what the "chkbfs" utility is for, mainly).
  - add delayed index updating (+ delete actions to solve the issue above)
- - multiple log files, parallel transactions?
+ - multiple log files, parallel transactions? (note that parallel transactions would require more locking to be done)
  - variable sized log file
  - as long as we have a fixed-sized log file, it should be possible to reserve space for a transaction to be able to decide if batching it is possible
 
@@ -38,7 +38,7 @@ BPlusTree
  - BPlusTree::Remove() could trigger CachedNode::Free() to go through the free nodes list and free all pages at the end of the data stream
  - BPlusTree::Remove() could let the tree shrink (simple kind of reorganization)
  - updating the TreeIterators doesn't work yet for duplicates (which may be a problem if a duplicate node will go away after a remove)
- - BPlusTree::RemoveDuplicate() could spread the contents of duplicate node with only a few entries to save some space (right now, only empty nodes are freed)
+ - BPlusTree::RemoveDuplicate() could merge the contents of duplicate node with only a few entries to save some space (right now, only empty nodes are freed)
 
 
 Inode
@@ -46,7 +46,6 @@ Inode
  - exchange Inode::OldLastModified() with Inode::NewLastModified(), and don't change the last_modified field directly in Inode::WriteAt() for consistency in case of a crash
  - the size is only updated in bfs_close() - but if the system crashes before, the entry in the size index doesn't match the one in the inode anymore - it would be better to let the data.size not reflect the real file size in this case (since the max_xxx_range entries are always correct)
  - Inode::FillGapWithZeros() currently disabled; apart from being slow, it really shouldn't be executed while a transaction is running, because that stops all other threads from doing anything (which can be a long time for a 100 MB file)
- - Inode::Name() is not safe - should be replaced with: status Inode::GetName(char *)
 
 
 Indices
@@ -56,7 +55,7 @@ Indices
 
 Attributes
 
- - bfs_write_attr() doesn't check if the attribute data may fit into the small_data region if there already is that attribute as an attribute file
+ - Inode::WriteAttribute() doesn't check if the attribute data may fit into the small_data region if there already is that attribute as an attribute file
 
 
 Volume
@@ -71,7 +70,6 @@ kernel_interface
 general stuff
 
  - There are also some comments with a leading "ToDo:" directly in the code which may not be mentioned here.
- - implement chkbfs functionality in BFS (with a small ioctl API for the shell command)
  - implement mkbfs (try to do it in OpenBeOS style directly - only write the super block from user space)