Commit Graph

103 Commits

Author SHA1 Message Date
Alexander Boettcher
22d71d5a8b os: use Mutex/Blockade
Issue #3612
2020-04-17 12:40:12 +02:00
Norman Feske
2912096f6e vfs: distinguish NO_PERM from NO_ENTRY in unlink
This patch changes the 'Single_file_system' to return NO_PERM only if
the to-be-unlinked file corresponds to the single file. This way, a
<rom> co-mounted with a <ram> file-system does not stand in the way of
unlinking files from the <ram>. The concrete symptom occurred the
following scenario:

  <vfs>
    <dir name="home">
      <ram/>
      <rom name="..."/>
    </dir>
  </vfs>

The following sequence of commands wrongly resulted in "Operation not
permitted":

 $ mkdir -p /home/a/b/c
 $ rm -f /home/a/b/c/d

In this case, rm should not fail (unlink should return ENOENT)

Fixes #3690
2020-03-26 11:38:55 +01:00
Josef Söntgen
6addd6cf1e os: fix Node_rwx::rwx
Fixes #3658.
2020-02-27 14:46:57 +01:00
Norman Feske
3ac970ac1d Streamline Timestamp::INVALID values
This is a follow-up patch for issue #1784 that solves two
inconsistencies.

- The Vfs::Timestamp::INVALID matches File_system::Timestamp::INVALID
- The Noux libc plugin tests for Timestamp::INVALID instead of a
  positive value.

The patch fixes the mtime info as shown in directory listings in
Sculpt's inspect window.
2019-11-21 14:26:27 +01:00
Emery Hemingway
c51b4b5742 New VFS plugin for emulating POSIX pipes
Add a new plugin for creating pipes between pairs of VFS handles. It is
intended to replace the libc_pipe plugin, one of the last remaining libc
plugins.

In contrast to the libc_pipe plugin, this plugin defers cross-handle
notification until I/O signal handling rather than block and unblock
readers using a semaphore. This is a performance regression in the case
of multiple threads blocking on a pipe, but shall be an intermediate
mechanism pending renovations within the libc VFS and threading layers.
As a side effect, threads blocked on a pipe might not be resumed until
the main thread suspends and dispatches I/O signals.

The "test-libc_pipe" test has been adjusted to use the VFS pipe plugin
and tests both local pipes and pipes hosted remotely in the VFS server.

Merge adaptations (such as EOF handling, adjustment to VFS/libc
interface changes) by Norman Feske.

Fix #2303
2019-11-19 14:54:13 +01:00
Norman Feske
7549189f88 vfs: watch support for Readonly_value_file_system
This patch adds support for watch notifications for the
'Readonly_value_file_system', which is often used by VFS plugins to
implement pseudo files. It thereby enables VFS clients to respond to
VFS-plugin events (think of terminal resize) dynamically.

Fixes #3523
2019-11-19 14:42:23 +01:00
Norman Feske
5ab1505d43 file system: enhanced file status info
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.
2019-11-19 14:23:56 +01:00
Josef Söntgen
9a82bbb54d vfs: add modification time member to directory_service
Issue #1784.
2019-11-19 14:17:30 +01:00
Emery Hemingway
a635873568 VFS: Replace global response handlers with local handlers
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
2019-04-09 12:30:34 +02:00
Emery Hemingway
800b4e44b1 Reduce Vfs::Vfs_handle::Context to empty struct type
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
2019-04-01 19:33:47 +02:00
Emery Hemingway
93fb79f357 Check for existing directories at Vfs::Dir_file_system
Return OPENDIR_ERR_NODE_ALREADY_EXISTS for existing directories.
Remove deprecated 'is_directory' method.

Fix #3083
2019-03-04 10:57:04 +01:00
Norman Feske
b3727a9b46 Add missing override annotations
Issue #3159
2019-02-19 11:12:11 +01:00
Norman Feske
6b94e65a95 os: avoid using deprecated APIs
Issue #1987
Issue #3125
2019-01-30 13:49:54 +01:00
Christian Prochaska
fd7ab79fe0 vfs: implement 'complete_sync()' in 'Single_file_system'
Fixes #3047
2018-11-27 11:38:13 +01:00
Christian Prochaska
9a2af89c4e vfs: use correct enum values in 'Dir_file_system::open_composite_dirs()'
Fixes #2968
2018-09-13 15:21:11 +02:00
Emery Hemingway
08b774e318 VFS: add an error to to the Sync_result enum
Sync errors can be used to indicate failed writes across the File_system
session.

Ref #2920
2018-08-02 14:36:49 +02:00
Christian Prochaska
b2f7a6a934 vfs_lxip: look up path in 'leaf_path()'
Fixes #2913
2018-08-02 14:36:43 +02:00
Christian Prochaska
e3005266b6 vfs: no 'handle_io_response()' in regular VFS functions
Calling 'handle_io_response()' in a regular VFS function (in contrast to a
post-signal hook) can cause problems if the caller of the VFS function holds
a lock which prevents the io response handler from returning.

With this commit, the user of the VFS becomes responsible for unblocking
threads which might be blocking after a failed 'queue_read()', 'queue_sync()'
or 'write()' call.

Fixes #2896
2018-08-02 14:36:43 +02:00
Emery Hemingway
e8dc6c84a4 Add missing XML header to vfs/file_system.h
Ref #2870
2018-07-03 09:39:34 +02:00
Emery Hemingway
29c08d4751 Fix types for VFS error printing
Ref #2793
2018-05-30 13:36:14 +02:00
Emery Hemingway
483d005350 VFS: detect root dir based on config node type
Ref #2782
2018-05-03 15:32:00 +02:00
Emery Hemingway
0b980073c1 VFS: close handles via handle method
The using pattern 'handle->close' is less error prone than attempting
'handle->ds().close(handle)' or 'fs.close(handle)'.

Ref #2782
2018-05-03 15:31:57 +02:00
Norman Feske
0a72b37363 vfs: Simple::env::apply_config 2018-04-19 13:38:33 +02:00
Emery Hemingway
3c07860aad VFS: watch result is ERR_UNACCESSIBLE by default
Ref #2745
2018-04-19 12:38:50 +02:00
Emery Hemingway
97f50e8e15 VFS: dir fs Opendir must open at least one directory to succeed
Ref #2745
2018-04-19 12:38:50 +02:00
Emery Hemingway
82a683eccc VFS: construct file-systems using Vfs::Env object
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
2018-04-19 12:38:27 +02:00
Emery Hemingway
9c6b720ec1 Notification support for the VFS library
Add a new 'Vfs_watch_handle' type to the VFS interface. This handle type
will pass a handle context up through the I/O handler to the application
when a notification event occurs.

Watch support implemented for RAM and File_system plugins, all other
file-systems return WATCH_ERR_STATIC by default.

Test at run/fs_rom_update_ram and run/fs_rom_update_fs.

Fix #1934
2018-04-10 11:11:51 +02:00
Norman Feske
07cd0d5809 vfs: add 'Readonly_value_file_system'
This file system is meant as a building block for pseudo file systems
that host a directory of several small files where each corresponds to
an attribute of the pseudo file system.
2018-04-10 11:09:18 +02:00
Norman Feske
48c5707a0c vfs: relax root_dir argument of 'Dir_file_system'
By letting the 'Dir_file_system' accept an arbitrary 'File_system'
as root directory, we can use the 'Dir_file_system' as a building
block for creating other file-system types.
2018-04-10 11:09:18 +02:00
Norman Feske
b0b92e4ee2 vfs: pass root directory to plugins
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
2018-04-10 11:09:17 +02:00
Emery Hemingway
013eb506a8 Vfs::Dir_file_system: do not use Vfs_handle for opening directories as files
The Dir_file_system uses static cast to convert handles from the
application to a plugin local type. For this reason, only the local
handle type may be returned from 'opendir' or 'open'. This fixes the
unexpected behavior when opening directories as files.

Fix #2533
2018-02-15 10:22:09 +01:00
Emery Hemingway
c7d0accac0 VFS: catch Out_of_ram and Out_of_cap exceptions
Catch out of RAM and capability exceptions and return error values.
Abort opening a composite directory at Dir_file_system where an
opendir call on any child file-system returns an OUT_OF_RAM or
OUT_OF_CAPS error.

Ref #2642
2018-02-14 20:41:07 +01:00
Josef Söntgen
4009239328 vfs: skip synced file systems in complete_sync
Fixes #2606.
2018-01-17 12:14:43 +01:00
Norman Feske
eba9c15746 Follow practices suggested by "Effective C++"
The patch adjust the code of the base, base-<kernel>, and os repository.
To adapt existing components to fix violations of the best practices
suggested by "Effective C++" as reported by the -Weffc++ compiler
argument. The changes follow the patterns outlined below:

* A class with virtual functions can no longer publicly inherit base
  classed without a vtable. The inherited object may either be moved
  to a member variable, or inherited privately. The latter would be
  used for classes that inherit 'List::Element' or 'Avl_node'. In order
  to enable the 'List' and 'Avl_tree' to access the meta data, the
  'List' must become a friend.

* Instead of adding a virtual destructor to abstract base classes,
  we inherit the new 'Interface' class, which contains a virtual
  destructor. This way, single-line abstract base classes can stay
  as compact as they are now. The 'Interface' utility resides in
  base/include/util/interface.h.

* With the new warnings enabled, all member variables must be explicitly
  initialized. Basic types may be initialized with '='. All other types
  are initialized with braces '{ ... }' or as class initializers. If
  basic types and non-basic types appear in a row, it is nice to only
  use the brace syntax (also for basic types) and align the braces.

* If a class contains pointers as members, it must now also provide a
  copy constructor and assignment operator. In the most cases, one
  would make them private, effectively disallowing the objects to be
  copied. Unfortunately, this warning cannot be fixed be inheriting
  our existing 'Noncopyable' class (the compiler fails to detect that
  the inheriting class cannot be copied and still gives the error).
  For now, we have to manually add declarations for both the copy
  constructor and assignment operator as private class members. Those
  declarations should be prepended with a comment like this:

        /*
         * Noncopyable
         */
        Thread(Thread const &);
        Thread &operator = (Thread const &);

  In the future, we should revisit these places and try to replace
  the pointers with references. In the presence of at least one
  reference member, the compiler would no longer implicitly generate
  a copy constructor. So we could remove the manual declaration.

Issue #465
2018-01-17 12:14:35 +01:00
Sebastian Sumpf
9c852c750a vfs: handle root directory explicitly
This makes '/' and the actual root of VFS distinguishable. A VFS root
may contain one ore more '/' entries for each file system. 'opendir' for
the VFS root opens all file systems via 'open_composite_dir', while
'opendir' for '/' only returns a VFS handle.

Fixes #2569
2017-11-30 11:23:10 +01:00
Emery Hemingway
07b36573ea Restrict VFS Dir_filesystem allocations to 'opendir' only
Allocations made at the client-side of the VFS must be contained within
functions that may return errors indicating resource exhaustion.

Fix #2569
2017-11-30 11:23:02 +01:00
Emery Hemingway
a0c0f3d7c9 Print support for VFS errors
Ref #2569
2017-11-30 11:23:02 +01:00
Josef Söntgen
e1ada57bfa vfs: use unsigned 64bit for media size ioctl
Fixes #2523.
2017-10-05 17:40:02 +02:00
Christian Prochaska
b0935ef9b2 VFS: nonblocking interface
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
2017-08-28 16:49:38 +02:00
Emery Hemingway
1eb37fbe22 VFS: move 'sync' from 'File_system' to 'Directory_service'
The the parent 'Directory_service' interface is reachable from
'Vfs_handle', whereas the 'File_system' interface is not.

Fix #2437
Ref #2422
2017-06-12 14:32:07 +02:00
Norman Feske
29b8d609c9 Adjust file headers to refer to the AGPLv3 2017-02-28 12:59:29 +01:00
Josef Söntgen
69c48a3626 os: refactor Global_file_system_factory
The global file system factory is now created explicitly and the
global singleton accessor function was removed.

Fixes #2281.
2017-02-28 12:59:23 +01:00
Christian Helmuth
61b6dccf13 Queued read/write/read_ready in VFS and servers 2017-02-23 15:03:28 +01:00
Sebastian Sumpf
aa602032dd vfs: dynamic configuration support 2017-02-23 14:54:48 +01:00
Christian Helmuth
f9389109bf Support select in libc VFS plugin by read_ready() 2017-02-07 11:12:29 +01:00
Christian Helmuth
c0d61858c3 Support for suspendable read in VFS and libC
The support has two parts. First, a VFS plugin now gets passed an
I/O-response handler callback on construction, which informs users of the
VFS that an I/O event occurred. This enables, for example, the libC to
check if blocking read can be completed. Further, the VFS file I/O
interface provides now functions for suspendable reads, i.e.,
queue_read() and complete_read().
2017-02-07 11:12:27 +01:00
Emery Hemingway
bae4ce5360 lib/vfs: deduplicate symlink and single_file
Issue #1891
2016-11-08 15:26:31 +01:00
Emery Hemingway
ddf3716cff vfs: pass Env and allocator when creating file-systems
Fix #1891
2016-11-08 15:26:31 +01:00
Emery Hemingway
beebd394fc lib/vfs: seperate implemention and API headers
Issue #1891
2016-11-08 15:26:30 +01:00
Norman Feske
17c79a9e23 base: avoid use of deprecated base/printf.h
Besides adapting the components to the use of base/log.h, the patch
cleans up a few base headers, i.e., it removes unused includes from
root/component.h, specifically base/heap.h and
ram_session/ram_session.h. Hence, components that relied on the implicit
inclusion of those headers have to manually include those headers now.

While adjusting the log messages, I repeatedly stumbled over the problem
that printing char * arguments is ambiguous. It is unclear whether to
print the argument as pointer or null-terminated string. To overcome
this problem, the patch introduces a new type 'Cstring' that allows the
caller to express that the argument should be handled as null-terminated
string. As a nice side effect, with this type in place, the optional len
argument of the 'String' class could be removed. Instead of supplying a
pair of (char const *, size_t), the constructor accepts a 'Cstring'.
This, in turn, clears the way let the 'String' constructor use the new
output mechanism to assemble a string from multiple arguments (and
thereby getting rid of snprintf within Genode in the near future).

To enforce the explicit resolution of the char * ambiguity, the 'char *'
overload of the 'print' function is marked as deleted.

Issue #1987
2016-08-29 17:27:10 +02:00