ext2: implements metadata_csum and 64bit features.

* Some PVS-Studio warnings are removed.
* fixes hardlink count in source and destination folders on rename.
* tested with fstorture and fsx (one job).
* add new definitions.
* import crc32c code from BSD.
* add some consistency checks at mount.
* DirectoryIterator::_AllocateBestEntryInBlock(), the direntry is checked for
consistency before using it, which should avoid crashing on bad data.
* DirectoryIterator::_SplitIndexedBlock(): the dotdot entry length should
include the dot and dotdot entries length.

Change-Id: I0f80d73b65b1ae6ddb2e746a6f85ef806f23dbb0
Reviewed-on: https://review.haiku-os.org/c/haiku/+/1735
Reviewed-by: waddlesplash <waddlesplash@gmail.com>

ext2: fixes 64 bit warnings

Patch from Janito Ferreira Filho (aka jjvf): this is the result of his GSoC assignment "Implement ext2/3 Read and Write Support for Haiku".
* Tested and checked most features and fs operations, while passing successfully the Linux fsck. Though the implementation still needs more testing and is to be used with
caution, it's better in my mind to have the code committed now given the size of the patch.
* Code style isn't extensively checked but is mostly OK. Code review is welcome.
Some notes from Janito:
* Sparse files aren't supported and hard links aren't supported. Write attributes methods aren't activated nor tested.
* Journaling needs more testing to make sure it behaves in a compatible way to Ext3, and support for the different modes hasn't been implemented (due to the block
and file cache incompatibility). Correct revoke management is also lacking, as is proper management of the superblock state and copies and block group copies.
* The code is partly based and inspired by the BFS implementation. Author information might need to be fixed.

I'd like to congratulate and thank Janito for his hard work to bring the implementation to the current state. I hope he'll keep on maintaining it and become a regular
contributor/committer.



git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@38573 a95241bf-73f2-0310-859d-f6bbb57e9c96

ext2: fixes 64 bit warnings

Patch from Janito Ferreira Filho (aka jjvf): this is the result of his GSoC assignment "Implement ext2/3 Read and Write Support for Haiku".
* Tested and checked most features and fs operations, while passing successfully the Linux fsck. Though the implementation still needs more testing and is to be used with
caution, it's better in my mind to have the code committed now given the size of the patch.
* Code style isn't extensively checked but is mostly OK. Code review is welcome.
Some notes from Janito:
* Sparse files aren't supported and hard links aren't supported. Write attributes methods aren't activated nor tested.
* Journaling needs more testing to make sure it behaves in a compatible way to Ext3, and support for the different modes hasn't been implemented (due to the block
and file cache incompatibility). Correct revoke management is also lacking, as is proper management of the superblock state and copies and block group copies.
* The code is partly based and inspired by the BFS implementation. Author information might need to be fixed.

I'd like to congratulate and thank Janito for his hard work to bring the implementation to the current state. I hope he'll keep on maintaining it and become a regular
contributor/committer.



git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@38573 a95241bf-73f2-0310-859d-f6bbb57e9c96