ext2: fix unused-but-set variable

This variable was introduced in hrev38573 which is the conclusion of
a GSoC project by jvff to add write support to the ext2 driver.
It has been unused for 13 years, I think it is safe to remove.

Change-Id: I8ae4635dbc39f108b769d90b92e5545f8183a10d
Reviewed-on: https://review.haiku-os.org/c/haiku/+/6715
Reviewed-by: Fredrik Holmqvist <fredrik.holmqvist@gmail.com>

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

* added flex group, dirnlink and gdtchecksum features for ext4.
* I reused crc_table.cpp from the UDF filesystem and switched it to have the reversed algorithm,
then generated the table in CRCTable.cpp
* added a binary search for extent tree leaves.
* fixed a check in InodeAllocator::New().


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@40129 a95241bf-73f2-0310-859d-f6bbb57e9c96

* added fsblock_t and fileblock_t definitions, used them when needed.
* validate fBlockShift in superblock.
* Volume::AllocateBlocks() now uses an absolute fsblock instead of a blockgroup related fsblock.
* AllocationBlockGroup now provides absolute fsblock values.
* added support for extents feature: ExtentStream class is the equivalent for DataStream class for extent operations.
The extent tree implementation is very basic, should work for normal growing/shrinking
operations, but not for sparse files. When enlarging a file and extent tree is full,
the root is moved in a new block and a new level is added on top. Extents can usually
be extended when adjacent blocks are allocated. Shrinking happens by removing leafs
one after another.
* removed empty IndexedDirectoryIterator.*


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@39886 a95241bf-73f2-0310-859d-f6bbb57e9c96

DirectoryIterator changes:
* RemoveEntry(): set inode id to zero when reaching the end of block
* FindEntry(): keep on searching if Get() returns B_BAD_DATA
* added _Offset() based on fLogicalBlock and fDisplacement
* Next(): keep on searching when inode id is zero; also when entry length is zero, keep on with next block
* added GetNext() to get the next valid entry.
* Get(): now returns B_BAD_DATA on a zero length or inode id.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@39343 a95241bf-73f2-0310-859d-f6bbb57e9c96

Volume: don't use a block allocator when mounting readonly.
BitmapBlock: also use file system blocks, current type is off_t. Also added more trace.
BlockAllocator: added an assert and more trace


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@39302 a95241bf-73f2-0310-859d-f6bbb57e9c96

* switched more uint32 to off_t for 64bit support
* added error messages in InodeAllocator, Inode
* if BlockAllocator can't initialize, don't fail completely but switch to readonly
* fixed a bug in FindNextMarked() for bitmaps with a length non multiple of 32
* Inode::FindBlock() now returns an optional block_run length, useful for get_file_map()
* added flag for Inode for extents


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@39234 a95241bf-73f2-0310-859d-f6bbb57e9c96

* added some support for 64bit feature: extended struct ext2_block_group, block number types changed from uint32 to off_t
* added error traces, asserts
* BitmapBlock::CheckUnmarked() and CheckMarked() computed a wrong remainingBits and mask


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@39203 a95241bf-73f2-0310-859d-f6bbb57e9c96

* added support for huge_file feature, untested (need a >2TB file)
* actually checks for readonly features if mounting read-write
* don't use a journal when mounting readonly
* DataStream::_BlocksNeeded(): in case of double or triple indirects,
compute the additional blocks needed using the difference between the
old and new indirects blocks. This was resulting in a bad NumBlocks on an inode
* BitmapBlock: mark methods missed an iteration when the startingBit was zero.
Some blocks were then allocated two times (at most 32 for each allocation run).


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@38950 a95241bf-73f2-0310-859d-f6bbb57e9c96

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

* added flex group, dirnlink and gdtchecksum features for ext4.
* I reused crc_table.cpp from the UDF filesystem and switched it to have the reversed algorithm,
then generated the table in CRCTable.cpp
* added a binary search for extent tree leaves.
* fixed a check in InodeAllocator::New().


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@40129 a95241bf-73f2-0310-859d-f6bbb57e9c96

* added fsblock_t and fileblock_t definitions, used them when needed.
* validate fBlockShift in superblock.
* Volume::AllocateBlocks() now uses an absolute fsblock instead of a blockgroup related fsblock.
* AllocationBlockGroup now provides absolute fsblock values.
* added support for extents feature: ExtentStream class is the equivalent for DataStream class for extent operations.
The extent tree implementation is very basic, should work for normal growing/shrinking
operations, but not for sparse files. When enlarging a file and extent tree is full,
the root is moved in a new block and a new level is added on top. Extents can usually
be extended when adjacent blocks are allocated. Shrinking happens by removing leafs
one after another.
* removed empty IndexedDirectoryIterator.*


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@39886 a95241bf-73f2-0310-859d-f6bbb57e9c96

DirectoryIterator changes:
* RemoveEntry(): set inode id to zero when reaching the end of block
* FindEntry(): keep on searching if Get() returns B_BAD_DATA
* added _Offset() based on fLogicalBlock and fDisplacement
* Next(): keep on searching when inode id is zero; also when entry length is zero, keep on with next block
* added GetNext() to get the next valid entry.
* Get(): now returns B_BAD_DATA on a zero length or inode id.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@39343 a95241bf-73f2-0310-859d-f6bbb57e9c96

Volume: don't use a block allocator when mounting readonly.
BitmapBlock: also use file system blocks, current type is off_t. Also added more trace.
BlockAllocator: added an assert and more trace


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@39302 a95241bf-73f2-0310-859d-f6bbb57e9c96

* switched more uint32 to off_t for 64bit support
* added error messages in InodeAllocator, Inode
* if BlockAllocator can't initialize, don't fail completely but switch to readonly
* fixed a bug in FindNextMarked() for bitmaps with a length non multiple of 32
* Inode::FindBlock() now returns an optional block_run length, useful for get_file_map()
* added flag for Inode for extents


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@39234 a95241bf-73f2-0310-859d-f6bbb57e9c96

* added some support for 64bit feature: extended struct ext2_block_group, block number types changed from uint32 to off_t
* added error traces, asserts
* BitmapBlock::CheckUnmarked() and CheckMarked() computed a wrong remainingBits and mask


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@39203 a95241bf-73f2-0310-859d-f6bbb57e9c96

* added support for huge_file feature, untested (need a >2TB file)
* actually checks for readonly features if mounting read-write
* don't use a journal when mounting readonly
* DataStream::_BlocksNeeded(): in case of double or triple indirects,
compute the additional blocks needed using the difference between the
old and new indirects blocks. This was resulting in a bad NumBlocks on an inode
* BitmapBlock: mark methods missed an iteration when the startingBit was zero.
Some blocks were then allocated two times (at most 32 for each allocation run).


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@38950 a95241bf-73f2-0310-859d-f6bbb57e9c96

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