btrfs: implement btrfs_write_fs_info

Change-Id: I507fc4154f8a11235b6b6f8812c3b38924f533f7
Reviewed-on: https://review.haiku-os.org/c/haiku/+/1560
Reviewed-by: Adrien Destugues <pulkomandy@gmail.com>

btrfs: partially implement filesystem initialization

Change-Id: I7fb3340dc39b3331d30e5113b5860d936efab253
Reviewed-on: https://review.haiku-os.org/c/1395
Reviewed-by: Adrien Destugues <pulkomandy@gmail.com>

BTRFS: Add author and license.

Signed-off-by: Augustin Cavalier <waddlesplash@gmail.com>

BTRFS: Implement btrfs_create_dir that can create directories in most case.

We need to handle a case when node is full, the solution should be split or push data to another node.

Signed-off-by: Augustin Cavalier <waddlesplash@gmail.com>

BTRFS: Implement Create() that allocate new Inode object.

Signed-off-by: Augustin Cavalier <waddlesplash@gmail.com>

BTRFS: Implement GetNewBlock() function that will find the logical address for allocating and convert it to physical block.

Signed-off-by: Augustin Cavalier <waddlesplash@gmail.com>

BTRFS: Implement a simple journaling approach, this is not finished and mostly satisfy the need for passing Transaction object for many functions.

Some details about the current Journal:
* Journal can only end transaction.
* It holds a transaction id of fs (fCurrentGeneration) that increments each time a transaction starts.
* _TransactionWritten now just printing message.

Signed-off-by: Augustin Cavalier <waddlesplash@gmail.com>

BTRFS: Implement ExtentAllocator

There are 4 new classes, structs:
* CachedExtent, is a AVLTreeNode, caches the extent locating in extent tree, a extent can be free, allocated, metadata or a data extent. It also hold a references count,
that is incremented each time a new extent refer to it (COW) and item data, that is only for allocated extent (NULL for free).
* CachedTreeExtent, is a AVLTree, cache the whole extent tree and has CachedExtent as its node.
* BlockGroup represents the group of extents that represent the region for each type of allocated extent. For example, region for data extents, metada blocks. It
responsible for inserting nodes in CachedTreeExtent.
* And the final, ExtentAllocator it knows how to allocate/deallocate extents, but for now only the allocating is implemented, actually allocating and deallocating works
are already implemented, they are in functions _AddFreeExtent, _AddAllocatedExtent in CachedTreeExtent. However the deallocating is not needed for now, so it will be
finished later then.

Signed-off-by: Augustin Cavalier <waddlesplash@gmail.com>

BTRFS: Added retrieve Volume from BTree

BTRFS: Added retrieve sector size for later use

Signed-off-by: Adrien Destugues <pulkomandy@pulkomandy.tk>

BTRFS: code cleanups

* Removed struct keyword for declaring variable.
* Renamed BPlusTree to BTree because BtrFS use a variant of BTree not B+Tree.

Signed-off-by: Adrien Destugues <pulkomandy@pulkomandy.tk>

btrfs_shell for testing btrfs code.

* Adding Jamfile in src/tools/btrfs_shell and include the subdir in src/tools/Jamfile
* Adding system_dependencies.h in btrfs source to include all the system headers
* fs_shell wrapping for btrfs source. If FS_SHELL is defined, compile with fs_shell headers instead.
* Change macro BTRFS_SHELL to FS_SHELL
* Adding btrfs_std_ops function: fs_shell now can recognize and load module

btrfs: Code style

* Using tab instead of spaces
* Pointer/Reference should be next to type
* etc

* Implemented a read-only btrfs file system, tested with a 400MB image.
* Inline extent data isn't read with the file_cache yet as the data is not block aligned.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@40282 a95241bf-73f2-0310-859d-f6bbb57e9c96

* Implemented a read-only btrfs file system, tested with a 400MB image.
* Inline extent data isn't read with the file_cache yet as the data is not block aligned.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@40282 a95241bf-73f2-0310-859d-f6bbb57e9c96