genode

History

Stefan Kalkowski 786fe805da base: introduce caching attributes (fix #1184 ) On ARM it's relevant to not only distinguish between ordinary cached memory and write-combined one, but also having non-cached memory too. To insert the appropriated page table entries e.g.: in the base-hw kernel, we need to preserve the information about the kind of memory from allocation until the pager resolves a page fault. Therefore, this commit introduces a new Cache_attribute type, and replaces the write_combined boolean with the new type where necessary.		2014-06-26 10:57:26 +02:00
..
component.h	base: introduce caching attributes (fix #1184 )	2014-06-26 10:57:26 +02:00
driver.h	Move repositories to 'repos/' subdirectory	2014-05-14 16:08:00 +02:00
main.cc	Move repositories to 'repos/' subdirectory	2014-05-14 16:08:00 +02:00
partition_table.h	Move repositories to 'repos/' subdirectory	2014-05-14 16:08:00 +02:00
README	Move repositories to 'repos/' subdirectory	2014-05-14 16:08:00 +02:00
target.mk	Move repositories to 'repos/' subdirectory	2014-05-14 16:08:00 +02:00

README

This directory contains an implementation of a block-device-partition server.

Behavior
--------

The server uses Genode's block-session interfaces as both front and back end,
leading to the most common use case where this server will reside "between" a
block-driver server and a higher level component like a file-system server.

At startup, the partition server will try to parse the master boot record (MBR)
of its back-end block session. If no partition table is found, the whole block
device is exported as partition '0'. In the other case, the MBR and possible
extended boot records (EBRs) are parsed and offered as separate block sessions
to the front-end clients. The four primary partitions will receive partition
numbers '1' to '4' whereas the first logical partition will be assigned to '5'.

In order to route a client to the right partition, the server parses its
configuration section looking for 'policy' tags.

XML Syntax:
! <policy labal="<program name>" parition="<partition number>" />

Usage
-----

Configuration snippet with two clients and an (hypothetical) IDE driver:
!<start name="ata_driver">
!  <resource name="RAM" quantum="1M" />
!  <provides><service name="Block"/></provides>
!  <config ata="yes" />
!</start>
!
!<start name="part_blk">
!  <resource name="RAM" quantum="10M" />
!  <provides><service name="Block" /></provides>
!
!  <!-- route part_blk to the ata_driver -->
!  <route>
!    <any-service><child name="ata_driver"/> <parent/><any-child/></any-service>
!  </route>
!
!  <!-- allow program 'test-part1' to access logical partition '6', while program
!      'test-part2' receives access to primary partition 1 -->
!  <config>
!    <policy label="test-part1" partition="6"/>
!    <policy label="test-part2" partition="1"/>
!  </config>
!</start>
!
!<!-- part_blk clients -->
!<start name="test-part1">
!  <binary name="test-part"/>
!  <resource name="RAM" quantum="10M" />
!  <route>
!    <any-service> <child name="part_blk" /> <parent/> <any-child/> </any-service>
!  </route>
!</start>
!
!<start name="test-part2">
!  <binary name="test-part"/>
!  <resource name="RAM" quantum="10M" />
!  <route>
!    <any-service> <child name="part_blk" /> <parent/> <any-child/> </any-service>
!  </route>
!</start>