Merge commit '96dba7ef358153dd1a608ab45f52226d08d62e3c'

As part of the merge, fix some typos, adjust copyright headers, and apply a few
more minor changes.

9 files changed, 17 insertions, 320 deletions

diff --git a/community/gsoc/project_ideas.mdwn b/community/gsoc/project_ideas.mdwn
index 7338d57b..0e08532c 100644
--- a/community/gsoc/project_ideas.mdwn
+++ b/community/gsoc/project_ideas.mdwn
@@ -1,5 +1,5 @@
 [[!meta copyright="Copyright © 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015,
-2016 Free Software Foundation, Inc."]]
+2016, 2017 Free Software Foundation, Inc."]]
 
 [[!meta license="""[[!toggle id="license" text="GFDL 1.2+"]][[!toggleable
 id="license" text="Permission is granted to copy, distribute and/or modify this
@@ -100,11 +100,8 @@ project_ideas:
   "community/gsoc/project_ideas/virtualization
   community/gsoc/project_ideas/secure_chroot
   community/gsoc/project_ideas/package_manager
-  community/gsoc/project_ideas/xattr
   community/gsoc/project_ideas/driver_glue_code
-  community/gsoc/project_ideas/physical_memory_management
   community/gsoc/project_ideas/language_bindings
-  community/gsoc/project_ideas/file_locking
   community/gsoc/project_ideas/gdb
   community/gsoc/project_ideas/tcp_ip_stack
   community/gsoc/project_ideas/nfs
diff --git a/community/gsoc/project_ideas/driver_glue_code.mdwn b/community/gsoc/project_ideas/driver_glue_code.mdwn
index 0f921590..1771756e 100644
--- a/community/gsoc/project_ideas/driver_glue_code.mdwn
+++ b/community/gsoc/project_ideas/driver_glue_code.mdwn
@@ -1,5 +1,5 @@
-[[!meta copyright="Copyright © 2008, 2009, 2010, 2011, 2016 Free Software
-Foundation, Inc."]]
+[[!meta copyright="Copyright © 2008, 2009, 2010, 2011, 2016, 2017, 2018 Free
+Software Foundation, Inc."]]
 
 [[!meta license="""[[!toggle id="license" text="GFDL 1.2+"]][[!toggleable
 id="license" text="Permission is granted to copy, distribute and/or modify this
@@ -27,22 +27,24 @@ This is [[!GNU_Savannah_task 5488]].
 [[open issues/user-space device drivers]].
 [[open issues/device drivers and io systems]].
 
-The most promising approach for getting newer drivers seems to be [[DDE]]:
+The most promising approach for getting newer drivers seems to be the [[Rump_Kernel]]:
 it already does the hard work of providing an environment
 where the foreign drivers can run,
 and offers the additional benefit of being externally maintained.
-DDE also offers the necessary facilities
+Rump also offers the necessary facilities
 for running all drivers in separate userspace processes,
 which is more desirable than drivers running in the microkernel.
 
-[[Zheng Da|zhengda]] has already done considerable work on this.
+Robert Millan worked on a port of the Rump kernel, which allowed to run a sound
+driver in userland. This work now needs to be extended.
+
+[[Zheng Da|zhengda]] has already done considerable work on a similar approach, using [[DDE]]
 The basic framework for using DDE in the Hurd is present,
 and network card drivers are already working very well.
 However, this work isn't fully integrated in the Hurd yet.
 The additional kernel interfaces that were created for this
-are still prototypes, and will need to be reworked.
-Also, there is no build system for automatically compiling
-all Linux network card drivers in one go.
+are still prototypes, and will need to be reworked. This environment can be
+reused and polished for Rump.
 
 Other types of drivers are missing so far.
 Support for IDE drivers has been partially implemented,
@@ -51,13 +53,10 @@ To fully replace the old in-kernel drivers,
 further infrastructure will be necessary
 to make userspace disk drivers usable for the root filesystem.
 
-Some other subsystems are missing or incomplete in DDE itself,
-and will require additional work that is not specific to the Hurd implementation.
-
 The goal of this task is to fix at least one of the mentioned major shortcomings:
 rework the kernel interfaces;
-provide a streamlined build system for the drivers;
-finish IDE support;
+polish the rumpkernel changes;
+componentize the rumpkernel elements for sound;
 or implement support for some other subsystem.
 <!-- should probably provide separate task descriptions for each... -->
 
@@ -69,13 +68,4 @@ such as memory management for example.
 
 Possible mentors: Justus Winter (teythoon), Samuel Thibault (youpi)
 
-Exercise: Get one of the not yet integrated Linux network card drivers to work.
-(Note: This should be straightforward,
-once you have the framework properly built and set up...)
-
----
-
-
-# 2016-02-14, Justus Winter
-
-`s/dde/rump/g` of course.
+Exercise: Install and run the current rumpkernel library (librump0) and the corresponding mplayer, get it to run.
diff --git a/community/gsoc/project_ideas/dtrace.mdwn b/community/gsoc/project_ideas/dtrace.mdwn
deleted file mode 100644
index 6261c03e..00000000
--- a/community/gsoc/project_ideas/dtrace.mdwn
+++ /dev/null
@@ -1,62 +0,0 @@
-[[!meta copyright="Copyright © 2008, 2009, 2011 Free Software Foundation,
-Inc."]]
-
-[[!meta license="""[[!toggle id="license" text="GFDL 1.2+"]][[!toggleable
-id="license" text="Permission is granted to copy, distribute and/or modify this
-document under the terms of the GNU Free Documentation License, Version 1.2 or
-any later version published by the Free Software Foundation; with no Invariant
-Sections, no Front-Cover Texts, and no Back-Cover Texts.  A copy of the license
-is included in the section entitled [[GNU Free Documentation
-License|/fdl]]."]]"""]]
-
-[[!meta title="Kernel Instrumentation"]]
-
-[[!tag open_issue_gnumach]]
-
-One of the main problems of the current Hurd implementation is very poor
-[[open_issues/performance]]. While we have a bunch of ideas what could cause the performance
-problems, these are mostly just guesses. Better understanding what really
-causes bad performance is necessary to improve the situation.
-
-For that, we need tools for performance measurements. While all kinds of more
-or less specific [[open_issues/profiling]] tools could be conceived, the most promising and
-generic approach seems to be a framework for logging certain events in the
-running system (both in the microkernel and in the Hurd servers). This would
-allow checking how much time is spent in certain modules, how often certain
-situations occur, how things interact, etc. It could also prove helpful in
-debugging some issues that are otherwise hard to find because of complex
-interactions.
-
-The most popular kernel instrumentation framework is Sun's dtrace,
-originally written for Solaris,
-but also adopted by some other systems.
-However, the GPL-incompatible license means it can't be used in Linux,
-and thus Linux developers created their own frameworks instead:
-first [[SystemTap]], and now [[LTTng]].
-
-In 2008, Andrei Barbu did initial work on kernel probes for the Hurd.
-However, not all of his patches got merged,
-because some turned out not to be fully functional.
-Also, he didn't get around to work on userspace probes,
-nor on a nice frontend for writing test scripts employing the probes.
-
-The goal of this project is to make the instrumentation framework
-more usable and complete,
-and to better integrate it in the Hurd.
-For that, the student will have to work
-on some real profiling and/or debugging tasks,
-and fix any shortcomings he encounters in the framework.
-
-This is a pretty involved task.
-Previous experience with low-level programming is a must;
-and it also requires a good grasp on interactions in complex systems.
-
-To work on this project,
-the student will have to get familiar with GNU Mach.
-(The microkernel employed by the Hurd.)
-Some understanding of other aspects of the Hurd will also be required,
-depending on the exact nature of the profiling/debugging performed.
-
-Possible mentors: Samuel Thibault (youpi)
-
-Exercise: Use the existing probes to perform some simple measurement.
diff --git a/community/gsoc/project_ideas/file_locking.mdwn b/community/gsoc/project_ideas/file_locking.mdwn
deleted file mode 100644
index ebb322f1..00000000
--- a/community/gsoc/project_ideas/file_locking.mdwn
+++ /dev/null
@@ -1,42 +0,0 @@
-[[!meta copyright="Copyright © 2008, 2009, 2012, 2014 Free Software Foundation,
-Inc."]]
-
-[[!meta license="""[[!toggle id="license" text="GFDL 1.2+"]][[!toggleable
-id="license" text="Permission is granted to copy, distribute and/or modify this
-document under the terms of the GNU Free Documentation License, Version 1.2 or
-any later version published by the Free Software Foundation; with no Invariant
-Sections, no Front-Cover Texts, and no Back-Cover Texts.  A copy of the license
-is included in the section entitled [[GNU Free Documentation
-License|/fdl]]."]]"""]]
-
-[[!meta title="Fix and Complete File Locking Support"]]
-
-Over the years, [[UNIX]] has acquired a host of different file locking mechanisms.
-Some of them work on the Hurd, while others are buggy or only partially
-implemented. This breaks many applications.
-
-The goal is to make all file locking mechanisms work properly. This requires
-finding all existing shortcomings (through systematic testing and/or checking
-for known issues in the bug tracker and mailing list archives), and fixing
-them. The biggest missing feature is record locking, i.e. the lockf variant,
-which needs a complete implementation.
-
-This task will require digging into parts of the code to understand how file
-locking works on the Hurd. Only general programming skills are required.
-
-A preliminary patch is [[!GNU_Savannah_patch 332 desc="available"]].
-
-Possible mentors: Samuel Thibault (youpi)
-
-Exercise: Find one of the existing issues, either by looking at the task/bug
-filed on [[open_issues/file_locking]], on
-trackers on savannah, or by trying things out yourself; and take a go at it.
-Note though that most of these issues are probably not trivial -- it's quite
-likely that you won't be able to actually fix any of them in the time available
-during the application process. However, you might be able to spot something
-else that could be improved while looking into this.
-
-If after trying for a while you haven't found anything easy enough to improve
-in the locking-related code, talk to us about some alternative exercise task.
-Perhaps you actually find something you could do while looking through the bug
-tracker or trying stuff yourself in search of locking issues :-)
diff --git a/community/gsoc/project_ideas/physical_memory_management.mdwn b/community/gsoc/project_ideas/physical_memory_management.mdwn
deleted file mode 100644
index 1bb6a760..00000000
--- a/community/gsoc/project_ideas/physical_memory_management.mdwn
+++ /dev/null
@@ -1,51 +0,0 @@
-[[!meta copyright="Copyright © 2015, 2016 Free Software Foundation, Inc."]]
-
-[[!meta license="""[[!toggle id="license" text="GFDL 1.2+"]][[!toggleable
-id="license" text="Permission is granted to copy, distribute and/or modify this
-document under the terms of the GNU Free Documentation License, Version 1.2 or
-any later version published by the Free Software Foundation; with no Invariant
-Sections, no Front-Cover Texts, and no Back-Cover Texts.  A copy of the license
-is included in the section entitled
-[[GNU Free Documentation License|/fdl]]."]]"""]]
-
-[[!meta title="Physical memory management"]]
-
-GNU Mach is currently suffering from severe limitations caused by the way
-it manages physical memory. For example, since it requires pages to be mapped
-in kernel space in order to be used, the maximum amount of usable physical
-memory is currently around 800MB (or 1.8GB if a 2/2 split is set). And
-because the page allocator is unable to easily return blocks of contiguous
-pages, the kernel has to use virtual memory to provide contiguity.
-But the kernel virtual space is separate from the direct mapping of
-physical memory, so the larger it is, the less physical pages available.
-The size of the kernel space is currently around 200MB, with around 100MB
-for kernel objects. This small size prevents the system from achieving
-scalability, since a panic occurs when the kernel is unable to allocate
-a kernel object such as a port. In addition, the kernel uses mainly tables
-to store IPC rights. When a table is full, it is enlarged through a kernel
-specific version of realloc(). When a file system starts managing many
-files (e.g. because some of their content is cached in physical memory),
-these tables can get big enough to make realloc() fail because of
-fragmentation.
-
-The goal of this project is to make as much physical memory available as
-possible for both the kernel and applications, by rewriting the page
-allocator into a buddy allocator to support contiguous block allocations,
-using it directly instead of virtual memory as the backend of the slab
-allocator for kernel objects, and, if time allows it, transform IPC right
-tables (e.g. into radix trees) and get rid of realloc().
-
-This project requires a good understanding of virtual memory (both physical
-mappings at the MMU level and virtual mappings at the VM level), and strong
-skills in C programming. Note that some work has already been done in the
-X15 project about this, and can be reused as a reference.
-
-Useful links :
-
- * <https://www.sceen.net/mapping-physical-memory-directly/>
-
- * <http://git.sceen.net/rbraun/x15.git/>
-
- * <https://git.sceen.net/rbraun/librbraun.git/plain/rdxtree.h>
-
-Possible mentors: Richard Braun
diff --git a/community/gsoc/project_ideas/sound.mdwn b/community/gsoc/project_ideas/sound.mdwn
deleted file mode 100644
index 8411831b..00000000
--- a/community/gsoc/project_ideas/sound.mdwn
+++ /dev/null
@@ -1,42 +0,0 @@
-[[!meta copyright="Copyright © 2008, 2009 Free Software Foundation, Inc."]]
-
-[[!meta license="""[[!toggle id="license" text="GFDL 1.2+"]][[!toggleable
-id="license" text="Permission is granted to copy, distribute and/or modify this
-document under the terms of the GNU Free Documentation License, Version 1.2 or
-any later version published by the Free Software Foundation; with no Invariant
-Sections, no Front-Cover Texts, and no Back-Cover Texts.  A copy of the license
-is included in the section entitled
-[[GNU Free Documentation License|/fdl]]."]]"""]]
-
-[[!meta title="Sound Support"]]
-
-The Hurd presently has no sound support.  Fixing this, [[!GNU_Savannah_task
-5485]], requires two steps: the first is to port some other kernel's drivers to
-[[GNU_Mach|microkernel/mach/gnumach]] so we can get access to actual sound
-hardware.  The second is to implement a userspace server ([[hurd/translator]]),
-that implements an interface on top of the kernel device that can be used by
-applications -- probably OSS or maybe ALSA.
-
-Completing this task requires porting at least one driver (e.g. from Linux) for
-a popular piece of sound hardware, and the basic userspace server. For the
-driver part, previous experience with programming kernel drivers is strongly
-advisable. The userspace part requires some knowledge about programming Hurd
-translators, but shouldn't be too hard.
-
-Once the basic support is working, it's up to the student to use the remaining
-time for porting more drivers, or implementing a more sophisticated userspace
-infrastructure. The latter requires good understanding of the Hurd philosophy,
-to come up with an appropriate design.
-
-Another option would be to evaluate whether a driver that is completely running
-in user-space is feasible.  <!-- TODO.  Elaborate.  -->
-
-Possible mentors: Samuel Thibault (youpi)
-
-Exercise: This project requires kernel (driver framework) hacking as well as
-some Hurd server hacking; so the exercise should involve either of these, or
-even both. You could for example port some newer driver to run in the existing
-framework (see the [[device_driver|driver_glue_code]] project description), or
-try to make some fix(es) to the [unfinished random device
-implementation](http://savannah.gnu.org/patch/?6088) created by Michael
-Casadevall.
diff --git a/community/gsoc/project_ideas/sound/discussion.mdwn b/community/gsoc/project_ideas/sound/discussion.mdwn
deleted file mode 100644
index 4a95eb62..00000000
--- a/community/gsoc/project_ideas/sound/discussion.mdwn
+++ /dev/null
@@ -1,47 +0,0 @@
-[[!meta copyright="Copyright © 2013 Free Software Foundation, Inc."]]
-
-[[!meta license="""[[!toggle id="license" text="GFDL 1.2+"]][[!toggleable
-id="license" text="Permission is granted to copy, distribute and/or modify this
-document under the terms of the GNU Free Documentation License, Version 1.2 or
-any later version published by the Free Software Foundation; with no Invariant
-Sections, no Front-Cover Texts, and no Back-Cover Texts.  A copy of the license
-is included in the section entitled [[GNU Free Documentation
-License|/fdl]]."]]"""]]
-
-[[!taglink open_issue_documentation]]: update [[sound]] page.
-
-
-# IRC, freenode, #hurd, 2013-09-01
-
-    <rekado> I'm new to the hurd but I'd love to learn enough to work on sound
-      support.
-    <rekado>
-      http://darnassus.sceen.net/~hurd-web/community/gsoc/project_ideas/sound/
-      says drivers should be ported to GNU Mach as a first step.
-    <rekado> Is this information still current or should the existing Linux
-      driver be wrapped with DDE instead?
-    <auronandace> if i recall correctly dde is currently only being used for
-      network drivers. i'm not sure how much work would be involved for sound
-      or usb
-
-
-## IRC, freenode, #hurd, 2013-09-02
-
-    <rekado> The sound support proposal
-      (http://darnassus.sceen.net/~hurd-web/community/gsoc/project_ideas/sound/)
-      recommends porting some other kernel's sound driver to GNU Mach.  Is this
-      still current or should DDE be used instead?
-    <pinotree> rekado: dde or anything userspace-based is generally preferred
-    <braunr> rekado: both are about porting some other kernel's sound driver
-    <braunr> dde is preferred yes
-    <rekado> This email says that sound drivers are already partly working with
-      DDE: http://os.inf.tu-dresden.de/pipermail/l4-hackers/2009/004291.html
-    <rekado> So, should I just try to get some ALSA kernel parts to compile
-      with DDE?
-    <pinotree> well, what is missing is also the dde←→hurd glue
-    <braunr> rekado: there is also a problem with pci arbitration
-    <rekado> pinotree: I assumed DDEKit works with the hurd and we could use
-      any DDE/<other kernel> glue code with it
-    * rekado looks up pci arbitration
-    <pinotree> only for networking atm
-    <rekado> ah, I see.
diff --git a/community/gsoc/project_ideas/tcp_ip_stack.mdwn b/community/gsoc/project_ideas/tcp_ip_stack.mdwn
index 331336ac..f86dcf72 100644
--- a/community/gsoc/project_ideas/tcp_ip_stack.mdwn
+++ b/community/gsoc/project_ideas/tcp_ip_stack.mdwn
@@ -1,4 +1,5 @@
-[[!meta copyright="Copyright © 2008, 2009 Free Software Foundation, Inc."]]
+[[!meta copyright="Copyright © 2008, 2009, 2017 Free Software Foundation,
+Inc."]]
 
 [[!meta license="""[[!toggle id="license" text="GFDL 1.2+"]][[!toggleable
 id="license" text="Permission is granted to copy, distribute and/or modify this
@@ -34,7 +35,7 @@ make such a split later on feasible.
 
 This is [[!GNU_Savannah_task 5469]].
 
-Possible mentors: zhengda
+Possible mentors: youpi
 
 Exercise: You could try making some improvement to the existing pfinet
 implementation; or you could work towards running some existing userspace
diff --git a/community/gsoc/project_ideas/xattr.mdwn b/community/gsoc/project_ideas/xattr.mdwn
deleted file mode 100644
index 8e1a532b..00000000
--- a/community/gsoc/project_ideas/xattr.mdwn
+++ /dev/null
@@ -1,47 +0,0 @@
-[[!meta copyright="Copyright © 2009, 2016 Free Software Foundation, Inc."]]
-
-[[!meta license="""[[!toggle id="license" text="GFDL 1.2+"]][[!toggleable
-id="license" text="Permission is granted to copy, distribute and/or modify this
-document under the terms of the GNU Free Documentation License, Version 1.2 or
-any later version published by the Free Software Foundation; with no Invariant
-Sections, no Front-Cover Texts, and no Back-Cover Texts.  A copy of the license
-is included in the section entitled
-[[GNU Free Documentation License|/fdl]]."]]"""]]
-
-[[!meta title="Implement xattr Support"]]
-
-Extended attributes (xattr) are a standardized, generic method for storing
-additional metadata along with a file (inode). Most modern UNIX filesystems
-support xattrs.
-
-In general, xattrs should be used sparingly, as they are less transparent than
-data stored as explicit file contents; however, there are some cases where they
-really make sense. The Hurd's variant of ext2 presently uses some additional
-fields in the inode to store Hurd-specific metadata: most notable passive
-translator settings. As these fields are Hurd-specific, they can't be accessed
-by the standard methods from Linux for example, so it's not possible to fully
-work with a Hurd filesystem on GNU/Linux (copy, backup etc.); and also, even
-when on Hurd, only tools that explicitly support the Hurd-specific information
-can handle them.
-
-Using extended attributes instead of custom fields for the Hurd-specific
-information would be very helpful.
-
-The most important goal of this project thus is to make the Hurd ext2fs server
-able to store and read the Hurd-specific information with extended attributes
-instead of the custom fields, so it become accessible from other systems. Being
-able to access the information through the standard xattr API instead of
-Hurd-specific calls is also desirable. (And in turn requires implementing the
-generic xattr API first, which can be useful for other purposes as well.)
-
-Completing this project will require digging into some parts of the Hurd, but
-it should be quite doable without previous Hurd experience. Some experience
-with xattrs might help a bit, but shouldn't be really necessary either.
-
-Some previous work on xattr support is [[available|open_issues/xattr]], and
-might serve as a starting point.
-
-Possible mentors: Justus Winter (teythoon), Samuel Thibault (youpi)
-
-Exercise: Implement support for different inode sizes (other than 128 bytes) in
-Hurd's ext2fs.