This patch extends the 'File_system::Status',
'File_system::Directory_entry', and the related 'Vfs' types with
the following additional information:
- Distinction between continuous and transactional files (Node_type)
(issue #3507)
- Readable, writeable, and executable attributes (Node_rwx),
replacing the former 'mode' bits
(issue #3030)
The types 'Node_rwx', 'Node_type' are defined twice,
once for the VFS (vfs/types.h) and once for the 'File_system'
session (file_system_session/file_system_session.h).
Similarly, there is a direct correspondance between
'Vfs::Directory_service::Dirent' and 'File_system::Directory_entry'.
This duplication of types follows the existing pattern of keeping the
VFS and file-system session independent from each other.
Replace the I/O response handler that is passed to the VFS at
construction with an object that is dynamically attached to handles.
This object shall also accept read-ready notifications, and plugins are
encouraged to keep handles awaiting ready-ready notifications separate
from handles that await I/O progress.
Replace the use of handle lists in plugins with handle queues, this
makes the code easier to understand and the ordering of notifications to
the application more explicit.
These changes replace the use of the Post_signal_hook from all VFS
plugins, applications must assume that read-ready and I/O notifications
occur during I/O signal dispatch and use an Io_progress_handler at its
entrypoints to defer response until after signal dispatching.
Fix#3257
The "Vfs::Vfs_handle" type should not contain any public members that
can be initialized by the VFS internally and by the application, so
remove inheritance from the "Genode::list::Element" class. The VFS
plugins must instead use lists of "Vfs::Vfs_handle" sub-classes, the
lifetime of which are always managed by the plugin.
Ref #3036
Use a single timeout scheduler passed during lxip instantiation for
both timers and 'schedule_timeout' facilites rather than instantiate
two timer sessions and signal handlers. This reduces the library's
capability cost and initialization time.
Fix#2961
The libc sockets implementation already syncs socket control files after
writes, so sync errors will induce failures for operations such as
"connect".
Fix#2920
Socket_fs sockets are now created each time a 'new_socket' control file
is opened, not each time a 'new_socket' file is read. When a handle on a
'new_socket' file is closed the socket and its socket files are
destroyed. The accept control file on a listening socket reads "1" or
reads nothing to indicate a client connection is queued. Client sockets
are accepted by opening an 'accept_socket' file in the listen socket
directory. This file behaves like the aforementioned 'new_socket' file.
Ref #2707
Reduce the size and forward compatibility of VFS file-system
constructors by passing an object holding accessors for 'Genode::Env',
'Genode::Allocator', response handlers, and the root file-system.
Fix#2742
This patch enables the use of the VFS from VFS plugins by passing a
reference of the root directory to the constructors of file-system
instances. Since it changes the signature of 'Vfs::Dir_file_system',
any code that uses the VFS directly requires an adaptation.
Fixes#2701
The VFS library can be used in single-threaded or multi-threaded
environments and depending on that, signals are handled by the same thread
which uses the VFS library or possibly by a different thread. If a VFS
plugin needs to block to wait for a signal, there is currently no way
which works reliably in both environments.
For this reason, this commit makes the interface of the VFS library
nonblocking, similar to the File_system session interface.
The most important changes are:
- Directories are created and opened with the 'opendir()' function and the
directory entries are read with the recently introduced 'queue_read()'
and 'complete_read()' functions.
- Symbolic links are created and opened with the 'openlink()' function and
the link target is read with the 'queue_read()' and 'complete_read()'
functions and written with the 'write()' function.
- The 'write()' function does not wait for signals anymore. This can have
the effect that data written by a VFS library user has not been
processed by a file system server yet when the library user asks for the
size of the file or closes it (both done with RPC functions at the file
system server). For this reason, a user of the VFS library should
request synchronization before calling 'stat()' or 'close()'. To make
sure that a file system server has processed all write request packets
which a client submitted before the synchronization request,
synchronization is now requested at the file system server with a
synchronization packet instead of an RPC function. Because of this
change, the synchronization interface of the VFS library is now split
into 'queue_sync()' and 'complete_sync()' functions.
Fixes#2399
Emery Hemingway
Christian Prochaska
Sebastian Sumpf
Norman Feske
Emery Hemingway
Stefan Kalkowski
Christian Helmuth
Martin Stein