genode

History

Alexander Boettcher accc7e7521 fs servers: handle result propagation better This patch removes the notion of partial writes from the file-system servers. Since write operations are asynchronously submitted, they are expected to succeed completely, except for I/O errors. I/O errors are propagated with the write acknowledgement but those are usually handled out of band at the client side. Partial writes must never occur because they would go undetected by clients, which usually don't wait for the completion of each single write operation. Until now, most file-system servers returned the number of written bytes in the acknowledgement packet. If a server managed to write a part of the request only, it issued the acknowledgement immediately where it should have cared about writing the remaining part first. The patch detects such misbehaving server-side code. If partial writes unexpectedly occur, it prints a message and leaves the corresponding request unacknowdleged. Issue #2672		2018-02-15 10:22:08 +01:00
..
include	rump_fs: add support for session (un-)mounting	2017-11-30 11:23:05 +01:00
lib	Exclude higher-level repos from strict warnings	2018-01-17 12:14:36 +01:00
patches	rump: handle error case in vm_vfs rump layer	2018-02-14 20:41:09 +01:00
ports	rump: handle error case in vm_vfs rump layer	2018-02-14 20:41:09 +01:00
recipes/src/rump	depot: update recipe hashes	2018-02-09 13:34:24 +01:00
run	rump: reduce size of rump	2017-11-30 11:23:19 +01:00
src	fs servers: handle result propagation better	2018-02-15 10:22:08 +01:00
README	Make label prefixing more strict	2016-11-30 13:37:07 +01:00
rump.list	rump: reduce size of rump	2017-11-30 11:23:19 +01:00

README

                             ================================
                             Genode's Rump Kernel kernel port
                             ================================

This repository contains the Genode version of the [http://wiki.netbsd.org/rumpkernel/ - rump kernel].
The kernel is currently used to gain file-system access from within Genode. In
order to achieve that, a Genode file-system server is located at
_src/server/rump_fs_. For accessing the server through the libc, the _libc_fs_
plugin can be facilitated, which is available in the _libports_ repository.

Building instructions
#####################

In order to build the file-system server, issue

! ./tool/ports/prepare_port dde_rump

from Genode's toplevel directory.


Add

! REPOSITORIES += $(GENODE_DIR)/repos/dde_rump

to your _etc/build.conf_ file of you build directory.

Finally,

! make server/rumps_fs

called from your build directory will build the server. You may also specify

! make run/rump_ext2

to run a simple test scenario.


Configuration
#############

Here is an example snippet that configures the server:

!<start name="rump_fs">
!  <resource name="RAM" quantum="8M" />
!  <provides><service name="File_system"/></provides>
!  <config fs="ext2fs"><default-policy root="/" writeable="yes"/></config>
!</start>

The server is looking for a service that provides a Genode block session. If
there is more than one block session in the system, the block session must be
routed to the right block-session server. The value of the _fs_ attribute of
the _config_ node can be one of the following: _ext2fs_ for EXT2, _cd9660_ for
ISO-9660, or _msdos_ for FAT file-system support. _root_ defines the directory
of the file system as seen as root directory by the client. The server hands
most of its RAM quota to the rump kernel. This means the larger the quota is,
the larger the internal block caches of the rump kernel will be.