file_system/fat: Rework driver for fs_shell support

* Introduce fat_shell for build system fat manipulation
* Will theoretically let us do away with mtools when we
have another internal tool for partition manipulation

Change-Id: I661be556e79009842f157a9402c8f85da85d6336
Reviewed-on: https://review.haiku-os.org/c/haiku/+/3556
Reviewed-by: Adrien Destugues <pulkomandy@gmail.com>

Added recursive_lock_transfer_lock() to the fs_shell.

* The rw_lock is now able to nest read/write locks when you have a write lock.
It follows the semantics of the BFS R/W lock, though, that is, if you unlock
your write lock before the read locks, the read locks effectively become
write locks, too.
* Added a mutex_transfer_lock() function that will allow you to unlock a mutex
in a different thread than the one which locked it (only matters if KDEBUG
is enabled, though).


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@26316 a95241bf-73f2-0310-859d-f6bbb57e9c96

* Added ReadLocker/WriteLocker classes to auto lock an rw_lock.
* Added *_init_etc() functions to the fs_shell.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@26302 a95241bf-73f2-0310-859d-f6bbb57e9c96

* Added a recursive_lock_trylock() function.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@26297 a95241bf-73f2-0310-859d-f6bbb57e9c96

* Made the private kernel locking primitives available to file systems as well.
* Applied Korli's mutex_unlock() fix to block_cache.cpp.
* Removed block_cache_priv.h, as it's no longer needed (moved its definitions
into block_cache.cpp, as in the kernel file).


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@26296 a95241bf-73f2-0310-859d-f6bbb57e9c96

Beginnings of a new, better portable FS shell with Haiku FS interface.
Doesn't do anything ATM, but already provides the required system
interface (VFS, caches, POSIX functions).


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@20859 a95241bf-73f2-0310-859d-f6bbb57e9c96

Added recursive_lock_transfer_lock() to the fs_shell.

* The rw_lock is now able to nest read/write locks when you have a write lock.
It follows the semantics of the BFS R/W lock, though, that is, if you unlock
your write lock before the read locks, the read locks effectively become
write locks, too.
* Added a mutex_transfer_lock() function that will allow you to unlock a mutex
in a different thread than the one which locked it (only matters if KDEBUG
is enabled, though).


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@26316 a95241bf-73f2-0310-859d-f6bbb57e9c96

* Added ReadLocker/WriteLocker classes to auto lock an rw_lock.
* Added *_init_etc() functions to the fs_shell.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@26302 a95241bf-73f2-0310-859d-f6bbb57e9c96

* Added a recursive_lock_trylock() function.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@26297 a95241bf-73f2-0310-859d-f6bbb57e9c96

* Made the private kernel locking primitives available to file systems as well.
* Applied Korli's mutex_unlock() fix to block_cache.cpp.
* Removed block_cache_priv.h, as it's no longer needed (moved its definitions
into block_cache.cpp, as in the kernel file).


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@26296 a95241bf-73f2-0310-859d-f6bbb57e9c96

Beginnings of a new, better portable FS shell with Haiku FS interface.
Doesn't do anything ATM, but already provides the required system
interface (VFS, caches, POSIX functions).


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@20859 a95241bf-73f2-0310-859d-f6bbb57e9c96