Move DeviceOpener class to a separate file.

It is used by several of the filesystems, so it seems a good idea to
move it to the shared/ directory.

UFS2, BFS, XFS, EXT2 and EXFAT are adjusted.

Change-Id: I493e37a1e7d3ae24251469f82befd985a3c1dbdd
Reviewed-on: https://review.haiku-os.org/c/haiku/+/2489
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: 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: 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>

Revert "Fix build problems of btrfs and packagefs for x86_64."

This reverts commit f272e63f393449d3a816970ca632764895a78cd6.

Fix build problems of btrfs and packagefs for x86_64.

* Both filesystems used to link to a static kernel-zlib, which
was being built with -fno-pic. This doesn't work on x86_64 as the
filesystem add-ons are meant to be relocatable, which requires their
code to be compiled as position independent.
Solve that by moving zlib into the kernel, so any add-on can just use
it from there (packagefs is mandatory, so we can't really do without
zlib anyway).

Fix race condition during build of some file systems.

* make sure the zlib package is available before trying to use zlib.h

Complete outsourcing of zlib

* Add optional packages Zlib and Zlib-devel.
* Simplify the build feature section for zlib and also extract the
source package.
* Replace all remaining references to the zlib instance in the tree and
remove it.

btrfs: added support for zlib decompression of inline extents.

Reuse code from tarfs to decompress zlib compressed inline extents.
No idea yet on how to decompress regular extents which are currently
served by the file cache.

added read only attribute support for btrfs.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@40335 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

Revert "Fix build problems of btrfs and packagefs for x86_64."

This reverts commit f272e63f393449d3a816970ca632764895a78cd6.

Fix build problems of btrfs and packagefs for x86_64.

* Both filesystems used to link to a static kernel-zlib, which
was being built with -fno-pic. This doesn't work on x86_64 as the
filesystem add-ons are meant to be relocatable, which requires their
code to be compiled as position independent.
Solve that by moving zlib into the kernel, so any add-on can just use
it from there (packagefs is mandatory, so we can't really do without
zlib anyway).

Fix race condition during build of some file systems.

* make sure the zlib package is available before trying to use zlib.h

Complete outsourcing of zlib

* Add optional packages Zlib and Zlib-devel.
* Simplify the build feature section for zlib and also extract the
source package.
* Replace all remaining references to the zlib instance in the tree and
remove it.

btrfs: added support for zlib decompression of inline extents.

Reuse code from tarfs to decompress zlib compressed inline extents.
No idea yet on how to decompress regular extents which are currently
served by the file cache.

added read only attribute support for btrfs.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@40335 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