userlandfs: implement get_fs_info using ioctl

This avoids introducing an entirely custom hook in FUSE.
It uses the ioctl hook in an unconventional way (calling it with no
valid fuse_file_info) but this can be fixed if a filesystem requires it
(by opening a file handle on /, doing the ioctl, then closing again).

An updated version of fusesmb-haiku is available and confirmed working:
https://github.com/haikuarchives/fusesmb-haiku

Change-Id: If1268113874363fa035e5340be75e9f5198216d6
Reviewed-on: https://review.haiku-os.org/c/haiku/+/5199
Reviewed-by: Adrien Destugues <pulkomandy@pulkomandy.tk>
Reviewed-by: waddlesplash <waddlesplash@gmail.com>
Tested-by: Commit checker robot <no-reply+buildbot@haiku-os.org>

userlandfs: compatibility with FUSE 2.9 and FUSE lowlevel API

- Import latest version of files from FUSE 2.9.9 (our last
synchronization was with 2.7.4)
- Adjust fuse pkgconfig file to use the POSIX error mapper
automatically, since that's required for all FUSE software
- Implement the lowlevel API in addition to the highlevel one. The
lowlevel API uses inode numbers to identify files, rather than paths,
making it a better fit to the userlandfs architecture.

The FUSE 2.x branch is not maintained anymore by FUSE developers,
however, pretty much no one migrated to FUSE 3.x. So it is more
interesting to implement, rather than 3.x.

Confirmed still working with sshfs and curlftpfs.

Example use:

I tested this with github.com/whoozle/android-file-transfer-linux

- Build the fuse library and copy it to ~/config/non-packaged/add-ons/userlandfs/
- Start the server: /system/servers/userlandfs_server aft-mtp-mount
- Connect your Android phone and put it in USB file transfer mode
- Mount the device: mount -t userlandfs -p 'aft-mtp-mount /boot/home/MyPhone -d -o use_ino' ~/MyPhone
- You can now access your phone data

Change-Id: Ic3efda7ffbc33737e6f4958428fb3ec9939ef105
Reviewed-on: https://review.haiku-os.org/c/haiku/+/5198
Tested-by: Commit checker robot <no-reply+buildbot@haiku-os.org>
Reviewed-by: waddlesplash <waddlesplash@gmail.com>

Implemented more of the detailed FUSE initialization functions for file systems
that use them directly instead of fuse_main().


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@30024 a95241bf-73f2-0310-859d-f6bbb57e9c96

* For every request to userland we also send the team/thread/user/group ID of
the current thread, now. Implemented by introducing a new base class
KernelRequest which has respective attributes.
* Server: RequestThreadContext does now also save the request that is being
processed. Furthermore some space has been reserved for file system specific
data, which can be initialized by the new
FileSystem::InitRequestThreadContext().
* FUSE library: Implemented fuse_get_context() using the new
RequestThreadContext feature.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@29872 a95241bf-73f2-0310-859d-f6bbb57e9c96

* Initialize fuse_config before parsing the arguments.
* Implemented fuse_is_lib_option() more correctly.
* Actually use the value of the "use_ino" option.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@29871 a95241bf-73f2-0310-859d-f6bbb57e9c96

Parse the FUSE library options. They aren't used yet, though.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@29844 a95241bf-73f2-0310-859d-f6bbb57e9c96

* More work on the file system initialization. Mounting/unmounting works now
with sshfs.
* Added basic node and entry management, which we need, since the FUSE
interface works with paths only, while our VFS plays with node IDs and
node cookies.
* Implemented most of the mandatory hooks (vnode operations, lookup, read stat,
open/close/read dir). I was hoping to get directory listings with sshfs now,
but as I had to find out, it implements the deprecated getdir() while we
only support the new {open,read,release}dir() interface yet.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@29619 a95241bf-73f2-0310-859d-f6bbb57e9c96

* Added "fuse_api.h" header wrapping the inclusion of <fuse.h>.
* Implemented the fuse_fs_*() functions.
* More work on the initialization procedure for the client file system. We do
now start a separate thread which calls the main() function. It won't return
from fuse_main_real() until unmounting the FS. We create a fuse_fs structure
and call the client FS initialization and cleanup hooks.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@29613 a95241bf-73f2-0310-859d-f6bbb57e9c96

Pass the file system name to the FileSystem base class and store it there.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@29610 a95241bf-73f2-0310-859d-f6bbb57e9c96

Added FileSystem and Volume subclasses for the FUSE interface. ATM they are
mostly skeletons, doing a bit of initialization.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@29604 a95241bf-73f2-0310-859d-f6bbb57e9c96

Implemented more of the detailed FUSE initialization functions for file systems
that use them directly instead of fuse_main().


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@30024 a95241bf-73f2-0310-859d-f6bbb57e9c96

* For every request to userland we also send the team/thread/user/group ID of
the current thread, now. Implemented by introducing a new base class
KernelRequest which has respective attributes.
* Server: RequestThreadContext does now also save the request that is being
processed. Furthermore some space has been reserved for file system specific
data, which can be initialized by the new
FileSystem::InitRequestThreadContext().
* FUSE library: Implemented fuse_get_context() using the new
RequestThreadContext feature.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@29872 a95241bf-73f2-0310-859d-f6bbb57e9c96

* Initialize fuse_config before parsing the arguments.
* Implemented fuse_is_lib_option() more correctly.
* Actually use the value of the "use_ino" option.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@29871 a95241bf-73f2-0310-859d-f6bbb57e9c96

Parse the FUSE library options. They aren't used yet, though.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@29844 a95241bf-73f2-0310-859d-f6bbb57e9c96

* More work on the file system initialization. Mounting/unmounting works now
with sshfs.
* Added basic node and entry management, which we need, since the FUSE
interface works with paths only, while our VFS plays with node IDs and
node cookies.
* Implemented most of the mandatory hooks (vnode operations, lookup, read stat,
open/close/read dir). I was hoping to get directory listings with sshfs now,
but as I had to find out, it implements the deprecated getdir() while we
only support the new {open,read,release}dir() interface yet.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@29619 a95241bf-73f2-0310-859d-f6bbb57e9c96

* Added "fuse_api.h" header wrapping the inclusion of <fuse.h>.
* Implemented the fuse_fs_*() functions.
* More work on the initialization procedure for the client file system. We do
now start a separate thread which calls the main() function. It won't return
from fuse_main_real() until unmounting the FS. We create a fuse_fs structure
and call the client FS initialization and cleanup hooks.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@29613 a95241bf-73f2-0310-859d-f6bbb57e9c96

Pass the file system name to the FileSystem base class and store it there.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@29610 a95241bf-73f2-0310-859d-f6bbb57e9c96

Added FileSystem and Volume subclasses for the FUSE interface. ATM they are
mostly skeletons, doing a bit of initialization.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@29604 a95241bf-73f2-0310-859d-f6bbb57e9c96