genode/os/src/server/iso9660
Norman Feske 9a00ad7ae3 Support for dynamic ROM sessions, fix #170
This patch introduces support for ROM sessions that update their
provided data during the lifetime of the session. The 'Rom_session'
interface had been extended with the new 'release()' and 'sigh()'
functions, which are needed to support the new protocol. All ROM
services have been updated to the new interface.

Furthermore, the patch changes the child policy of init
with regard to the handling of configuration files. The 'Init::Child'
used to always provide the ROM dataspace with the child's config file
via a locally implemented ROM service. However, for dynamic ROM
sessions, we need to establish a session to the real supplier of the ROM
data. This is achieved by using a new 'Child_policy_redirect_rom_file'
policy to handle the 'configfile' rather than handling the 'configfile'
case entirely within 'Child_config'.

To see the new facility in action, the new 'os/run/dynamic_config.run'
script provides a simple scenario. The config file of the test program
is provided by a service, which generates and updates the config data
at regular intervals.

In addition, new support has been added to let slaves use dynamic
reconfiguration. By using the new 'Child_policy_dynamic_rom_file', the
configuration of a slave can be changed dynamically at runtime via the
new 'configure()' function.

The config is provided as plain null-terminated string (instead of a
dataspace capability) because we need to buffer the config data anyway.
So there is no benefit of using a dataspace. For buffering configuration
data, a 'Ram_session' must be supplied. If no 'Ram_session' is specified
at construction time of a 'Slave_policy', no config is supplied to the
slave (which is still a common case).

An example for dynamically reconfiguring a slave is provided by
'os/run/dynamic_config_slave.run'.
2012-04-05 11:25:26 +02:00
..
backing_store.h Bump year in copyright headers to 2012 2012-01-03 15:35:05 +01:00
iso9660.cc Bump year in copyright headers to 2012 2012-01-03 15:35:05 +01:00
iso9660.h Bump year in copyright headers to 2012 2012-01-03 15:35:05 +01:00
main.cc Support for dynamic ROM sessions, fix #170 2012-04-05 11:25:26 +02:00
README Imported Genode release 11.11 2011-12-22 16:19:25 +01:00
target.mk Imported Genode release 11.11 2011-12-22 16:19:25 +01:00

This directory contains an implementation of an ISO 9660 file system.

Limitations
-----------

At the moment, the only file-name format supported is the Rock Ridge extension.
The ISO specified 8.3 upper-case-file names are not supported, as well as Joliet.

Usage
-----

The server requires an ATAPI-block device as back-end. Please have a look at
'os/src/drivers/atapi'. The front-end of the server is implemented as a ROM
session server. In order to access this server from your application, you need
to route the ROM session to the ISO-ROM-session server in Genode's configuration
file:

!<start name="test-iso">
!  <resource name="RAM" quantum="10M" />
!    <route>
!      <service name="ROM"><child name="iso9660"/></service>
!    </route>
!</start>

Currently, the RAM quota necessary to obtain a file from the ISO file system
is allocated on behalf of the ISO server. Please make sure to provide
sufficient RAM quota to the ISO server.