diff options
Diffstat (limited to 'libbsd.txt')
| -rw-r--r-- | libbsd.txt | 1331 |
1 files changed, 0 insertions, 1331 deletions
diff --git a/libbsd.txt b/libbsd.txt deleted file mode 100644 index 3d665500..00000000 --- a/libbsd.txt +++ /dev/null @@ -1,1331 +0,0 @@ -RTEMS BSD Library Guide -======================= -:toc: -:icons: -:numbered: -:website: http://www.rtems.org/ - -The libbsd makes FreeBSD subsystems like TCP/IP, USB, SD and some more usable -for RTEMS. It tries to follow the FreeBSD development as close as possible and -therefore is updated to the latest FreeBSD HEAD revision from time to time. -To find out which version of FreeBSD is currently used as the base version for -libbsd please take a look at the -https://git.rtems.org/rtems-libbsd/log/freebsd-org[freebsd-org] submodule. - -This is a guide which captures information on the -process of merging code from FreeBSD, building this library, -RTEMS specific support files, and general guidelines on what -modifications to the FreeBSD source are permitted. - -Goals of this effort are - -* update TCP/IP and provide USB in RTEMS, -* ease updating to future FreeBSD versions, -* ease tracking changes in FreeBSD code, -* minimize manual changes in FreeBSD code, and -* define stable kernel/device driver API which is implemented -by both RTEMS and FreeBSD. This is the foundation of the port. - -We will work to push our changes upstream to the FreeBSD Project -and minimize changes required at each update point. - -******************************************************************************* -This is a work in progress and is very likely to be incomplete. -Please help by adding to it. -******************************************************************************* - -== Getting Started - -=== Tool Chain === - -You need a tool chain for RTEMS based on the latest RTEMS Source Builder (RSB). - -=== Installation Overview === - -. You must configure your BSP with the +--disable-networking+ option to disable -the old network stack. Make sure no header files of the old network stack are -installed. - -. Clone the Git repository +git clone git://git.rtems.org/rtems-libbsd.git+. -. Change into the RTEMS BSD library root directory. -. If you want to run tests with a custom IP configuration instead of the default - one you can use an adjusted `config.inc` configuration file. -. Run +waf configure ...+. -. Run +waf+. -. Run +waf install+. - -Refer to the README.waf for Waf building instructions. - -Make sure the submodules have been initialised and are updated. If a 'git -status' says `rtems_waf` need updating run the submodule update command: - - $ git submodule sync - $ git submodule rtems_waf update - -=== Board Support Package Requirements === - -You need the latest RTEMS version to build the libbsd master. The Board -Support Package (BSP) must support the -http://www.rtems.org/onlinedocs/doxygen/cpukit/html/group\__rtems\__interrupt__extension.html[Interrupt Manager Extension] -// The first underscores have to be masked to stop asciidoc interpreting them -to make use of generic FreeBSD based drivers. - -=== Board Support Package Configuration and Build === - -You need to configure RTEMS for the desired BSP and install it. The BSP must -be configured with a disabled network stack. The BSD library containing the -new network stack is a separate package. Using a BSP installation containing -the old network stack may lead to confusion and unpredictable results. - -The following script is used to build the `arm/xilinx_zynq_a9_qemu` BSP for -our internal testing purposes: - -------------------------------------------------------------------------------- -#!/bin/sh - -cd ${HOME}/sandbox -rm -rf b-xilinx_zynq_a9_qemu -mkdir b-xilinx_zynq_a9_qemu -cd b-xilinx_zynq_a9_qemu -${HOME}/git-rtems/configure \ - --prefix=${HOME}/sandbox/install \ - --target=arm-rtems5 \ - --enable-rtemsbsp=xilinx_zynq_a9_qemu \ - --disable-networking && \ - make && \ - make install -------------------------------------------------------------------------------- - -The `arm/xilinx_zynq_a9_qemu` BSP running on the Qemu simulator has some -benefits for development and test of the BSD library - -* it offers a NULL pointer read and write protection, -* Qemu is a fast simulator, -* Qemu provides support for GDB watchpoints, -* Qemu provides support for virtual Ethernet networks, e.g. TUN and bridge -devices (you can run multiple test instances on one virtual network). - -=== BSD Library Configuration and Build === - -The build system based on the Waf build system. To build with Waf please refer -to the README.waf file. - -Note that the libbsd supports different buildsets. These can be selected with -the `--buildset=xxx.ini` option during the configure phase. Take a look at the -comments in `buildset/*.ini` to see which build sets are officially supported. - -You can also create and provide your own buildset configuration. But remember -that it's quite easy to break something by disabling the wrong modules. Only the -configurations in the `buildset` directory are officially maintained. - -===== Example Configuration for Network Tests ===== - -If you need some other IP configuration for the network tests that use a fixed -IP config you can copy `config.inc` to a location outside to the source tree and -adapt it. Then use the option `--net-test-config=NET_CONFIG` to pass the file to -waf's configure command. - -------------------------------------------------------------------------------- -NET_CFG_SELF_IP = 10.0.0.2 -NET_CFG_NETMASK = 255.255.0.0 -NET_CFG_PEER_IP = 10.0.0.1 -NET_CFG_GATEWAY_IP = 10.0.0.1 -------------------------------------------------------------------------------- - -=== BSD Library Initialization === - -To initialise the BSD Library create a suitable rc.conf file. The FreeBSD man -page rc.conf(5) provides the details needed to create a suitable format file: - - https://www.freebsd.org/cgi/man.cgi?rc.conf - -You can call one of three functions to run the initialisation once BSD has -initialised: - - - rtems_bsd_run_etc_rc_conf: Run /etc/rc.conf. - - rtems_bsd_run_rc_conf: Run a user supplied file. - - rtems_bsd_run_rc_conf_script: Run the in memory line feed separated text string. - -For exapmle: - - void - network_init(void) - { - rtems_status_code sc; - - sc = rtems_bsd_initialize(); - assert(sc == RTEMS_SUCCESSFUL); - - rtems_bsd_run_etc_rc_conf(true); /* verbose = true */ - -} - -By default the networking support is builtin. Other directives can be added and -are found in 'machine/rtems-bsd-rc-conf-directives.h'. Please check the file -for the list. - -The following network names are supported: - - cloned_interfaces - ifconfig_'interface' - defaultrouter - hostname - -For example: - - # - # My BSD initialisation. - # - hostname="myhost" - cloned_interfaces="vlan0 vlan1" - ifconfig_re0="inet inet 10.10.10.10 netmask 255.255.255.0" - fconfig_vlan0="inet 10.11.10.10 255.255.255.0 vlan 101 vlandev re0" - defaultrouter="10.10.10.1" - -You can also intialise the BSD library using code. The following code to -initialize the BSD library: - -------------------------------------------------------------------------------- -#include <assert.h> -#include <sysexits.h> - -#include <rtems/bsd/bsd.h> - -void -network_init(void) -{ - rtems_status_code sc; - int exit_code; - - sc = rtems_bsd_initialize(); - assert(sc == RTEMS_SUCCESSFUL); - - exit_code = rtems_bsd_ifconfig_lo0(); - assert(exit_code == EX_OK); -} -------------------------------------------------------------------------------- - -This performs the basic network stack initialization with a loopback interface. -Further initialization must be done using the standard BSD network -configuration commands -http://www.freebsd.org/cgi/man.cgi?query=ifconfig&sektion=8[IFCONFIG(8)] -using `rtems_bsd_command_ifconfig()` and -http://www.freebsd.org/cgi/man.cgi?query=route&sektion=8[ROUTE(8)] -using `rtems_bsd_command_route()`. For an example please have a look at -`testsuite/include/rtems/bsd/test/default-network-init.h`. - -=== Task Priorities and Stack Size === - -The default task priority is 96 for the interrupt server task (name "IRQS"), 98 -for the timer server task (name "TIME") and 100 for all other tasks. The -application may provide their own implementation of the -`rtems_bsd_get_task_priority()` function (for example in the module which calls -`rtems_bsd_initialize()`) if different values are desired. - -The task stack size is determined by the `rtems_bsd_get_task_stack_size()` -function which may be provided by the application in case the default is not -appropriate. - -=== Size for Allocator Domains === - -The size for an allocator domain can be specified via the -`rtems_bsd_get_allocator_domain_size()` function. The application may provide -their own implementation of the `rtems_bsd_get_allocator_domain_size()` -function (for example in the module which calls `rtems_bsd_initialize()`) if -different values are desired. The default size is 8MiB for all domains. - -=== Redirecting or Disabling the Output === - -A lot of system messages are printed to the stdout by default. If you want to -redirect them you can overwrite the default print handler. That can even be done -before the libbsd initialization to catch all messages. An example would look -like follows: - -------------------------------------------------------------------------------- -int my_vprintf_handler(int level, const char *fmt, va_list ap) { - /* Do something with the messages. */ - - return number_of_printed_chars; -} - -... - /* In your initialization: */ - rtems_bsd_vprintf_handler old; - old = rtems_bsd_set_vprintf_handler(my_vprintf_handler); -... -------------------------------------------------------------------------------- - -As a special case, you can set the `rtems_bsd_vprintf_handler_mute(...)` -provided by libbsd to suppress all output. - -== Network Stack Features - -http://roy.marples.name/projects/dhcpcd/index[DHCPCD(8)]:: DHCP client - -https://developer.apple.com/library/mac/documentation/Networking/Reference/DNSServiceDiscovery_CRef/Reference/reference.html[dns_sd.h]:: DNS Service Discovery - -http://www.opensource.apple.com/source/mDNSResponder/mDNSResponder-320.10/mDNSCore/mDNSEmbeddedAPI.h[mDNS]:: Multi-Cast DNS - -http://www.freebsd.org/cgi/man.cgi?query=unix&sektion=4[UNIX(4)]:: UNIX-domain protocol family - -http://www.freebsd.org/cgi/man.cgi?query=inet&sektion=4[INET(4)]:: Internet protocol family - -http://www.freebsd.org/cgi/man.cgi?query=inet6&sektion=4[INET6(4)]:: Internet protocol version 6 family - -http://www.freebsd.org/cgi/man.cgi?query=tcp&sektion=4[TCP(4)]:: Internet Transmission Control Protocol - -http://www.freebsd.org/cgi/man.cgi?query=udp&sektion=4[UDP(4)]:: Internet User Datagram Protocol - -http://www.freebsd.org/cgi/man.cgi?query=route&sektion=4[ROUTE(4)]:: Kernel packet forwarding database - -http://www.freebsd.org/cgi/man.cgi?query=bpf&sektion=4[BPF(4)]:: Berkeley Packet Filter - -http://www.freebsd.org/cgi/man.cgi?query=socket&sektion=2[SOCKET(2)]:: Create an endpoint for communication - -http://www.freebsd.org/cgi/man.cgi?query=kqueue&sektion=2[KQUEUE(2)]:: Kernel event notification mechanism - -http://www.freebsd.org/cgi/man.cgi?query=select&sektion=2[SELECT(2)]:: Synchronous I/O multiplexing - -http://www.freebsd.org/cgi/man.cgi?query=poll&sektion=2[POLL(2)]:: Synchronous I/O multiplexing - -http://www.freebsd.org/cgi/man.cgi?query=route&sektion=8[ROUTE(8)]:: Manually manipulate the routing tables - -http://www.freebsd.org/cgi/man.cgi?query=ifconfig&sektion=8[IFCONFIG(8)]:: Configure network interface parameters - -http://www.freebsd.org/cgi/man.cgi?query=netstat&sektion=1[NETSTAT(1)]:: Show network status - -http://www.freebsd.org/cgi/man.cgi?query=ping&sektion=8[PING(8)]:: Send ICMP ECHO_REQUEST packets to network hosts - -http://www.freebsd.org/cgi/man.cgi?query=ping6&sektion=8[PING6(8)]:: Send ICMPv6 ECHO_REQUEST packets to network hosts - -http://www.freebsd.org/cgi/man.cgi?query=sysctl&sektion=3[SYSCTL(3)]:: Get or set system information - -http://www.freebsd.org/cgi/man.cgi?query=resolver&sektion=3[RESOLVER(3)]:: Resolver routines - -http://www.freebsd.org/cgi/man.cgi?query=gethostbyname&sektion=3[GETHOSTBYNAME(3)]:: Get network host entry - -== Network Interface Drivers - -=== Link Up/Down Events - -You can notifiy the application space of link up/down events in your network -interface driver via the if_link_state_change(LINK_STATE_UP/LINK_STATE_DOWN) -function. The DHCPCD(8) client is a consumer of these events for example. -Make sure that the interface flag IFF_UP and the interface driver flag -IFF_DRV_RUNNING is set in case the link is up, otherwise ether_output() will -return the error status ENETDOWN. - -== Shell Commands - -=== HOSTNAME(1) - -In addition to the standard options the RTEMS version of the HOSTNAME(1) -command supports the -m flag to set/get the multicast hostname of the -mDNS resolver instance. See also rtems_mdns_sethostname() and -rtems_mdns_gethostname(). - -== Qemu - -Use the following script to set up a virtual network with three tap devices -connected via one bridge device. - -------------------------------------------------------------------------------- -#!/bin/sh -x - -user=`whoami` -interfaces=(1 2 3) - -tap=qtap -bri=qbri - -case $1 in - up) - sudo -i brctl addbr $bri - for i in ${interfaces[@]} ; do - sudo -i tunctl -t $tap$i -u $user ; - sudo -i ifconfig $tap$i up ; - sudo -i brctl addif $bri $tap$i ; - done - sudo -i ifconfig $bri up - ;; - down) - for i in ${interfaces[@]} ; do - sudo -i ifconfig $tap$i down ; - sudo -i tunctl -d $tap$i ; - done - sudo -i ifconfig $bri down - sudo -i brctl delbr $bri - ;; -esac -------------------------------------------------------------------------------- - -Connect your Qemu instance to one of the tap devices, e.g. - -------------------------------------------------------------------------------- -qemu-system-i386 -m 512 -boot a -cpu pentium3 \ - -drive file=$HOME/qemu/pc386_fda,index=0,if=floppy,format=raw \ - -drive file=fat:$HOME/qemu/hd,format=raw \ - -net nic,model=e1000,macaddr=0e:b0:ba:5e:ba:11 \ - -net tap,ifname=qtap1,script=no,downscript=no \ - -nodefaults -nographic -serial stdio -------------------------------------------------------------------------------- - -------------------------------------------------------------------------------- -qemu-system-arm \ - -serial null \ - -serial mon:stdio \ - -nographic \ - -M xilinx-zynq-a9 \ - -net nic,model=cadence_gem,macaddr=0e:b0:ba:5e:ba:11 \ - -net tap,ifname=qtap1,script=no,downscript=no \ - -m 256M \ - -kernel build/arm-rtems5-xilinx_zynq_a9_qemu/media01.exe -------------------------------------------------------------------------------- - -Make sure that each Qemu instance uses its own MAC address to avoid an address -conflict (or otherwise use it as a test). - -To connect the Qemu instances with your local network use the following -(replace 'eth0' with the network interface of your host). - -------------------------------------------------------------------------------- -ifconfig eth0 0.0.0.0 -brctl addif qbri eth0 -dhclient qbri -------------------------------------------------------------------------------- - -=== VDE and QEMU - -On FreeBSD you can create VDE or the Virtual Distributed Ethernet to create a -network environment that does not need to run qemu as root or needing to drop -the tap's privileges to run qemu. - -VDE creates a software switch with a default of 32 ports which means a single -kernel tap can support 32 qemu networking sessions. - -To use VDE you need to build qemu with VDE support. The RSB can detect a VDE -plug and enable VDE support in qemu when building. On FreeBSD install the VDE -support with: - - # pkg install -u vde2 - -Build qemu with the RSB. - -To network create a bridge and a tap. The network is 10.10.1.0/24. On FreeBSD -add to your /etc/rc.conf: - - cloned_interfaces="bridge0 tap0" - autobridge_interfaces="bridge0" - autobridge_bridge0="re0 tap0" - ifconfig_re0="up" - ifconfig_tap0="up" - ifconfig_bridge0="inet 10.1.1.2 netmask 255.255.255.0" - defaultrouter="10.10.1.1" - -Start the VDE switch as root: - - # sysctl net.link.tap.user_open=1 - # sysctl net.link.tap.up_on_open=1 - # vde_switch -d -s /tmp/vde1 -M /tmp/mgmt1 -tap tap0 -m 660 --mgmtmode 660 - # chmod 660 /dev/tap0 - -You can connect to the VDE switch's management channel using: - - $ vdeterm /tmp/mgmt1 - -To run qemu: - - $ qemu-system-arm \ - -serial null \ - -serial mon:stdio \ - -nographic \ - -M xilinx-zynq-a9 \ - -net nic,model=cadence_gem,macaddr=0e:b0:ba:5e:ba:11 \ - -net vde,id=vde0,sock=/tmp/vde1 - -m 256M \ - -kernel build/arm-rtems5-xilinx_zynq_a9_qemu/rcconf02.exe - -== Issues and TODO - -* PCI support on x86 uses a quick and dirty hack, see pci_reserve_map(). - -* Priority queues are broken with clustered scheduling. - -* Per-CPU data should be enabled once the new stack is ready for SMP. - -* Per-CPU NETISR(9) should be enabled onece the new stack is ready for SMP. - -* Multiple routing tables are not supported. Every FIB value is set to zero - (= BSD_DEFAULT_FIB). - -* Process identifiers are not supported. Every PID value is set to zero - (= BSD_DEFAULT_PID). - -* User credentials are not supported. The following functions allow the - operation for everyone - - prison_equal_ip4(), - - chgsbsize(), - - cr_cansee(), - - cr_canseesocket() and - - cr_canseeinpcb(). - -* A basic USB functionality test that is known to work on Qemu is desirable. - -* Adapt generic IRQ PIC interface code to Simple Vectored Interrupt Model - so that those architectures can use new TCP/IP and USB code. - -* freebsd-userspace/rtems/include/sys/syslog.h is a copy from the old - RTEMS TCP/IP stack. For some reason, the __printflike markers do not - compile in this environment. We may want to use the FreeBSD syslog.h - and get this addressed. - -* in_cksum implementations for architectures not supported by FreeBSD. - This will require figuring out where to put implementations that do - not originate from FreeBSD and are populated via the script. - -* MAC support functions are not thread-safe ("freebsd/lib/libc/posix1e/mac.c"). - -* IFCONFIG(8): IEEE80211 support is disabled. This module depends on a XML - parser and mmap(). - -* get_cyclecount(): The implementation is a security problem. - -* What to do with the priority parameter present in the FreeBSD synchronization - primitives and the thread creation functions? - -* TASKQUEUE(9): Support spin mutexes. - -* ZONE(9): Review allocator lock usage in rtems-bsd-chunk.c. - -* KQUEUE(2): Choose proper lock for global kqueue list. - -* TIMEOUT(9): Maybe use special task instead of timer server to call - callout_tick(). - -* sysctl_handle_opaque(): Implement reliable snapshots. - -* PING6(8): What to do with SIGALARM? - -* <sys/param.h>: Update Newlib to use a MSIZE of 256. - -* BPF(4): Add support for zero-copy buffers. - -* UNIX(4): Fix race conditions in the area of socket object and file node - destruction. Add support for file descriptor transmission via control - messages. - -* PRINTF(9): Add support for log(), the %D format specifier is missing in the - normal printf() family. - -* Why is the interrupt server used? The BSD interrupt handlers can block on -synchronization primitives like mutexes. This is in contrast to RTEMS -interrupt service routines. The BSPs using the generic interrupt support must -implement the `bsp_interrupt_vector_enable()` and -`bsp_interrupt_vector_disable()` routines. They normally enable/disable a -particular interrupt source at the interrupt controller. This can be used to -implement the interrupt server. The interrupt server is a task that wakes-up -in case an associated interrupt happens. The interrupt source is disabled in -a generic interrupt handler that wakes-up the interrupt server task. Once the -postponed interrupt processing is performed in the interrupt server the -interrupt source is enabled again. - -* Convert all BSP linkcmds to use a linkcmds.base so the sections are -easier to insert. - -* NIC Device Drivers -- Only common PCI NIC drivers have been included in the initial set. These -do not include any system on chip or ISA drivers. -- PCI configuration probe does not appear to happen to determine if a -NIC is in I/O or memory space. We have worked around this by using a -static hint to tell the fxp driver the correct mode. But this needs to -be addressed. -- The ISA drivers require more BSD infrastructure to be addressed. This was -outside the scope of the initial porting effort. - -== FreeBSD Source - -You should be able to rely on FreebSD manual pages and documentation -for details on the code itself. - -== BSD Library Source - -== Initialization of the BSD Library - -The initialization of the BSD library is based on the FreeBSD SYSINIT(9) -infrastructure. The key to initializing a system is to ensure that the desired -device drivers are explicitly pulled into the linked application. This plus -linking against the BSD library (`libbsd.a`) will pull in the necessary FreeBSD -infrastructure. - -The FreeBSD kernel is not a library like the RTEMS kernel. It is a bunch of -object files linked together. If we have a library, then creating the -executable is simple. We begin with a start symbol and recursively resolve all -references. With a bunch of object files linked together we need a different -mechanism. Most object files don't know each other. Lets say we have a driver -module. The rest of the system has no references to this driver module. The -driver module needs a way to tell the rest of the system: Hey, kernel I am -here, please use my services! - -This registration of independent components is performed by SYSINIT(9) and -specializations: - -http://www.freebsd.org/cgi/man.cgi?query=SYSINIT - -The SYSINIT(9) uses some global data structures that are placed in a certain -section. In the linker command file we need this: - -------------------------------------------------------------------------------- -.rtemsroset : { - KEEP (*(SORT(.rtemsroset.*))) -} - -.rtemsrwset : { - KEEP (*(SORT(.rtemsrwset.*))) -} -------------------------------------------------------------------------------- - -This results for example in this executable layout: - -------------------------------------------------------------------------------- -[...] - *(SORT(.rtemsroset.*)) - .rtemsroset.bsd.modmetadata_set.begin - 0x000000000025fe00 0x0 libbsd.a(rtems-bsd-init.o) - 0x000000000025fe00 _bsd__start_set_modmetadata_set - .rtemsroset.bsd.modmetadata_set.content - 0x000000000025fe00 0x8 libbsd.a(rtems-bsd-nexus.o) - .rtemsroset.bsd.modmetadata_set.content - 0x000000000025fe08 0x4 libbsd.a(kern_module.o) -[...] - .rtemsroset.bsd.modmetadata_set.content - 0x000000000025fe68 0x4 libbsd.a(mii.o) - .rtemsroset.bsd.modmetadata_set.content - 0x000000000025fe6c 0x4 libbsd.a(mii_bitbang.o) - .rtemsroset.bsd.modmetadata_set.end - 0x000000000025fe70 0x0 libbsd.a(rtems-bsd-init.o) - 0x000000000025fe70 _bsd__stop_set_modmetadata_set -[...] -.rtemsrwset 0x000000000030bad0 0x290 - *(SORT(.rtemsrwset.*)) - .rtemsrwset.bsd.sysinit_set.begin - 0x000000000030bad0 0x0 libbsd.a(rtems-bsd-init.o) - 0x000000000030bad0 _bsd__start_set_sysinit_set - .rtemsrwset.bsd.sysinit_set.content - 0x000000000030bad0 0x4 libbsd.a(rtems-bsd-nexus.o) - .rtemsrwset.bsd.sysinit_set.content - 0x000000000030bad4 0x8 libbsd.a(rtems-bsd-thread.o) - .rtemsrwset.bsd.sysinit_set.content - 0x000000000030badc 0x4 libbsd.a(init_main.o) -[...] - .rtemsrwset.bsd.sysinit_set.content - 0x000000000030bd54 0x4 libbsd.a(frag6.o) - .rtemsrwset.bsd.sysinit_set.content - 0x000000000030bd58 0x8 libbsd.a(uipc_accf.o) - .rtemsrwset.bsd.sysinit_set.end - 0x000000000030bd60 0x0 libbsd.a(rtems-bsd-init.o) - 0x000000000030bd60 _bsd__stop_set_sysinit_set -[...] -------------------------------------------------------------------------------- - -Here you can see, that some global data structures are collected into -continuous memory areas. This memory area can be identified by start and stop -symbols. This constructs a table of uniform items. - -The low level FreeBSD code calls at some time during the initialization the -mi_startup() function (machine independent startup). This function will sort -the SYSINIT(9) set and call handler functions which perform further -initialization. The last step is the scheduler invocation. - -The SYSINIT(9) routines are run in mi_startup() which is called by -rtems_bsd_initialize(). - -This is also explained in "The Design and Implementation of the FreeBSD -Operating System" section 14.3 "Kernel Initialization". - -In RTEMS we have a library and not a bunch of object files. Thus we need a way -to pull-in the desired services out of the libbsd. Here the -`rtems-bsd-sysinit.h` comes into play. The SYSINIT(9) macros have been -modified and extended for RTEMS in `<sys/kernel.h>`: - -------------------------------------------------------------------------------- -#ifndef __rtems__ -#define C_SYSINIT(uniquifier, subsystem, order, func, ident) \ - static struct sysinit uniquifier ## _sys_init = { \ - subsystem, \ - order, \ - func, \ - (ident) \ - }; \ - DATA_SET(sysinit_set,uniquifier ## _sys_init) -#else /* __rtems__ */ -#define SYSINIT_ENTRY_NAME(uniquifier) \ - _bsd_ ## uniquifier ## _sys_init -#define SYSINIT_REFERENCE_NAME(uniquifier) \ - _bsd_ ## uniquifier ## _sys_init_ref -#define C_SYSINIT(uniquifier, subsystem, order, func, ident) \ - struct sysinit SYSINIT_ENTRY_NAME(uniquifier) = { \ - subsystem, \ - order, \ - func, \ - (ident) \ - }; \ - RWDATA_SET(sysinit_set,SYSINIT_ENTRY_NAME(uniquifier)) -#define SYSINIT_REFERENCE(uniquifier) \ - extern struct sysinit SYSINIT_ENTRY_NAME(uniquifier); \ - static struct sysinit const * const \ - SYSINIT_REFERENCE_NAME(uniquifier) __used \ - = &SYSINIT_ENTRY_NAME(uniquifier) -#define SYSINIT_MODULE_REFERENCE(mod) \ - SYSINIT_REFERENCE(mod ## module) -#define SYSINIT_DRIVER_REFERENCE(driver, bus) \ - SYSINIT_MODULE_REFERENCE(driver ## _ ## bus) -#define SYSINIT_DOMAIN_REFERENCE(dom) \ - SYSINIT_REFERENCE(domain_add_ ## dom) -#endif /* __rtems__ */ -------------------------------------------------------------------------------- - -Here you see that the SYSINIT(9) entries are no longer static. The -\*_REFERENCE() macros will create references to the corresponding modules which -are later resolved by the linker. The application has to provide an object -file with references to all required FreeBSD modules. - -The FreeBSD device model is quite elaborated (with follow-ups): - -http://www.freebsd.org/cgi/man.cgi?query=driver - -The devices form a tree with the Nexus device at a high-level. This Nexus -device is architecture specific in FreeBSD. In RTEMS we have our own Nexus -device, see `rtemsbsd/bsp/bsp-bsd-nexus-devices.c`. - -=== SYSCTL_NODE Example - -During development, we had an undefined reference to -_bsd_sysctl__net_children that we had trouble tracking down. Thanks to -Chris Johns, we located it. He explained how to read SYSCTL_NODE -definitions. This line from freebsd/netinet/in_proto.c is attempting -to add the "inet" node to the parent node "_net". - ----- -SYSCTL_NODE(_net, PF_INET, inet, CTLFLAG_RW, 0, - "Internet Family"); ----- - -Our problem was that we could not find where _bsd_sysctl__net_children -was defined. Chris suggested that when in doubt compile with -save-temps -and look at the preprocessed .i files. But he did not need that. He -explained that this the symbol name _bsd_sysctl__net_children was -automatically generated by a SYSCTL_NODE as follows: - -* _bsd_ - added by RTEMS modifications to SYSCTL_NODE macro -* sysctl_ - boilerplace added by SYSCTL_NODE macro -* "" - empty string for parent node -* net - name of SYSCTL_NODE -* children - added by SYSCTL macros - -This was all generated by a support macro declaring the node as this: - ----- -struct sysctl_oid_list SYSCTL_NODE_CHILDREN(parent, name); ----- - -Given this information, we located this SYSCTL_NODE declaration in -kern/kern_mib.c - ----- -SYSCTL_NODE(, CTL_KERN, kern, CTLFLAG_RW, 0, - "High kernel, proc, limits &c"); ----- - -== Core FreeBSD APIs and RTEMS Replacements == - -=== SX(9) (Shared/exclusive locks) === - -http://www.freebsd.org/cgi/man.cgi?query=sx - -Binary semaphores (this neglects the ability to allow shared access). - -=== MUTEX(9) (Mutual exclusion) === - -http://www.freebsd.org/cgi/man.cgi?query=mutex - -Binary semaphores (not recursive mutexes are not supported this way). - -=== RWLOCK(9) (Reader/writer lock) === - -http://www.freebsd.org/cgi/man.cgi?query=rwlock - -POSIX r/w lock. - -=== RMLOCK(9) (Reader/writer lock optimized for mostly read access patterns) === - -Note: This object was implemented as a wrapper for RWLOCK in the rm_lock header file. - -http://www.freebsd.org/cgi/man.cgi?query=rmlock - -POSIX r/w lock. - -=== CONDVAR(9) (Condition variables) === - -http://www.freebsd.org/cgi/man.cgi?query=condvar - -POSIX condition variables with modifications (hack). - -=== CALLOUT(9) (Timer functions) === - -http://www.freebsd.org/cgi/man.cgi?query=callout - -Timer server. - -=== TASKQUEUE(9) (Asynchronous task execution) === - -http://www.freebsd.org/cgi/man.cgi?query=taskqueue - -TBD. - -=== KTHREAD(9), KPROC(9) (Tasks) === - -http://www.freebsd.org/cgi/man.cgi?query=kthread - -http://www.freebsd.org/cgi/man.cgi?query=kproc - -Tasks. - -=== ZONE(9) (Zone allocator) === - -http://www.freebsd.org/cgi/man.cgi?query=zone - -TBD. - -=== devfs (Device file system) === - -There is a minimal implementation based on IMFS. The mount point is fixed to -"/dev". Note that the devfs is only used by the cdev subsystem. cdev has been -adapted so that the full path (including the leading "/dev") is given to devfs. -This saves some copy operations. - -devfs_create() first creates the full path and then creates an IMFS generic node -for the device. - -TBD: remove empty paths on devfs_destroy(). - -=== psignal (Signals) === - -TBD. Seems to be not needed. - -=== poll, select === - -TBD. Seems to be not needed. - -=== RMAN(9) (Resource management) === - -http://www.freebsd.org/cgi/man.cgi?query=rman - -TBD. Seems to be not needed. - -=== DEVCLASS(9), DEVICE(9), DRIVER(9), MAKE_DEV(9) (Device management) === - -http://www.freebsd.org/cgi/man.cgi?query=devclass - -http://www.freebsd.org/cgi/man.cgi?query=device - -http://www.freebsd.org/cgi/man.cgi?query=driver - -http://www.freebsd.org/cgi/man.cgi?query=make_dev - -Use FreeBSD implementation as far as possible. FreeBSD has a nice API for -dynamic device handling. It may be interesting for RTEMS to use this API -internally in the future. - -=== BUS_SPACE(9), BUS_DMA(9) (Bus and DMA access) === - -http://www.freebsd.org/cgi/man.cgi?query=bus_space - -http://www.freebsd.org/cgi/man.cgi?query=bus_dma - -Likely BSP dependent. A default implementation for memory mapped linear access -is easy to provide. The current heap implementation supports all properties -demanded by bus_dma (including the boundary constraint). - -== RTEMS Replacements by File Description == - -Note: Files with a status of USB are used by the USB test and have at least -been partially tested. If they contain both USB and Nic, then they are used -by both and MAY contain methods that have not been tested yet. Files that -are only used by the Nic test are the most suspect. - ----- -rtems-libbsd File: rtems-bsd-assert.c -FreeBSD File: rtems-bsd-config.h redefines BSD_ASSERT. -Description: This file contains the support method rtems_bsd_assert_func(). -Status: USB, Nic - -rtems-libbsd File: rtems-bsd-autoconf.c -FreeBSD File: FreeBSD has BSP specific autoconf.c -Description: This file contains configuration methods that are used to setup the system. -Status: USB - -rtems-libbsd File: rtems-bsd-bus-dma.c -FreeBSD File: FreeBSD has BSP specific busdma_machdep.c -Description: -Status: USB, Nic - -rtems-libbsd File: rtems-bsd-bus-dma-mbuf.c -FreeBSD File: FreeBSD has BSP specific busdma_machdep.c -Description: -Status: Nic - -rtems-libbsd File: rtems-bsd-callout.c -FreeBSD File: kern/kern_timeout.c -Description: -Status: USB, Nic - -rtems-libbsd File: rtems-bsd-cam.c -FreeBSD File: cam/cam_sim.c -Description: -Status: USB - -rtems-libbsd File: rtems-bsd-condvar.c -FreeBSD File: kern/kern_condvar.c -Description: -Status: USB - -rtems-libbsd File: rtems-bsd-copyinout.c -FreeBSD File: bsp specific copyinout.c ) -Description: Note: The FreeBSD file is split with some methods being in rtems-bsd-support -Status: Nic - -rtems-libbsd File: rtems-bsd-delay.c -FreeBSD File: bsp specific file with multiple names -Description: -Status: USB, Nic - -rtems-libbsd File: rtems-bsd-descrip.c -FreeBSD File: kern/kern_descrip.c -Description: -Status: Nic - -rtems-libbsd File: rtems-bsd-generic.c -FreeBSD File: kern/sys_generic.c -Description: -Status: Nic - -rtems-libbsd File: rtems-bsd-init.c -FreeBSD File: N/A -Description: -Status: USB, Nic - -rtems-libbsd File: rtems-bsd-init-with-irq.c -FreeBSD File: N/A -Description: -Status: USB, Nic - -rtems-libbsd File: rtems-bsd-jail.c -FreeBSD File: kern/kern_jail.c -Description: -Status: USB, Nic - -rtems-libbsd File: rtems-bsd-lock.c -FreeBSD File: kern/subr_lock.c -Description: -Status: USB, Nic - -rtems-libbsd File: rtems-bsd-log.c -FreeBSD File: kern/subr_prf.c -Description: -Status: Nic - -rtems-libbsd File: rtems-bsd-malloc.c -FreeBSD File: kern/kern_malloc.c -Description: -Status: USB, Nic - -rtems-libbsd File: rtems-bsd-mutex.c -FreeBSD File: kern/kern_mutex.c -Description: -Status: USB, Nic - -rtems-libbsd File: rtems-bsd-newproc.c -FreeBSD File: N/A -Description: -Status: Nic - -rtems-libbsd File: rtems-bsd-nexus.c -FreeBSD File: bsp specific nexus.c -Description: -Status: USB - -rtems-libbsd File: rtems-bsd-panic.c -FreeBSD File: boot/common/panic.c -Description: -Status: USB, Nic - -rtems-libbsd File: rtems-bsd-rwlock.c -FreeBSD File: kern_rwlock.c -Description: -Status: USB, Nic - -rtems-libbsd File: rtems-bsd-shell.c -FreeBSD File: N/A -Description: -Status: USB - -rtems-libbsd File: rtems-bsd-signal.c -FreeBSD File: kern/kern_sig.c -Description: -Status: Nic - -rtems-libbsd File: rtems-bsd-smp.c -FreeBSD File: N/A -Description: -Status: Nic - -rtems-libbsd File: rtems-bsd-support.c -FreeBSD File: bsp specific copyinout.c -Description: Note: the FreeBSD file is split with some methods being in rtems-bsd-copyinout. -Status: USB, Nic - -rtems-libbsd File: rtems-bsd-sx.c -FreeBSD File: kern/kern_sx.c -Description: Status: USB, Nic - -rtems-libbsd File: rtems-bsd-synch.c -FreeBSD File: kern/kern_synch.c -Description: -Status: USB, Nic - -rtems-libbsd File: rtems-bsd-syscalls.c -FreeBSD File: User API for kern/uipc_syscalls.c -Description: -Status: Nic - -rtems-libbsd File: rtems-bsd-sysctlbyname.c -FreeBSD File: User API for sysctlbyname(3) -Description: -Status: - -rtems-libbsd File: rtems-bsd-sysctl.c -FreeBSD File: User API for sysctl(8) -Description: -Status: - -rtems-libbsd File: rtems-bsd-sysctlnametomib.c -FreeBSD File: User API for sysctlnametomib -Description: -Status: - -rtems-libbsd File: rtems-bsd-taskqueue.c -FreeBSD File: kern/subr_taskqueue.c -Description: -Status: Nic - -rtems-libbsd File: rtems-bsd-thread.c -FreeBSD File: kern/kern_kthread.c -Description: -Status: USB, Nic - -rtems-libbsd File: rtems-bsd-timeout.c -FreeBSD File: kern/kern_timeout.c -Description: -Status: Nic - -rtems-libbsd File: rtems-bsd-timesupport.c -FreeBSD File: kern/kern_clock.c -Description: -Status: Nic - -rtems-libbsd File: rtems-bsd-vm_glue.c -FreeBSD File: vm/vm_glue.c -Description: -Status: USB, Nic ----- - -== Notes by File == - -altq_subr.c - Arbitrary choices were made in this file that RTEMS would -not support tsc frequency change. Additionally, the clock frequency -for machclk_freq is always measured for RTEMS. - -conf.h - In order to add make_dev and destroy_dev, variables in the cdev -structure that were not being used were conditionally compiled out. The -capability of supporting children did not appear to be needed and was -not implemented in the rtems version of these routines. - -== NICs Status == - ----- -Driver Symbol Status -====== ====== ====== -RealTek _bsd_re_pcimodule_sys_init Links -EtherExpress _bsd_fxp_pcimodule_sys_init Links -DEC tulip _bsd_dc_pcimodule_sys_init Links -Broadcom BCM57xxx _bsd_bce_pcimodule_sys_init Links -Broadcom BCM4401 _bsd_bfe_pcimodule_sys_init Links -Broadcom BCM570x _bsd_bge_pcimodule_sys_init Needs Symbols (A) -E1000 IGB _bsd_igb_pcimodule_sys_init Links -E1000 EM _bsd_em_pcimodule_sys_init Links -Cadence ? Links, works. ----- - -To add a NIC edit rtemsbsd/include/bsp/nexus-devices.h and add the driver -reference to the architecture and/or BSP. For example to add the RealTek driver -add: - -SYSINIT_DRIVER_REFERENCE(re, pci); - -and to add the MII PHY driver add: - -SYSINIT_DRIVER_REFERENCE(rge, miibus); - -The PC BSP has these entries. - -Symbols (A) - pci_get_vpd_ident - -=== Cadence === - -The cadence driver works on the Xilinx Zynq platform. The hardware checksum -support works on real hardware but does not seem to be supported on qemu -therefore the default state is to disable TXCSUM and RXCSUM and this can be -enabled from the shell with: - - # ifconfig cgem0 rxcsum txcsum - -or with an ioctl call to the network interface driver with SIOCSIFCAP and the -mask IFCAP_TXCSUM and IFCAP_RXCSUM set. - -== PF (Firewall) == - -It is possible to use PF as a firewall. See -[https://www.freebsd.org/doc/handbook/firewalls-pf.html] for details on the -range of functions and for how to configure the firewall. - -The following is necessary to use PF on RTEMS: - -- You have to provide a +/etc/pf.os+ file. The firewall can use it for passive - OS fingerprinting. If you don't want to use this feature, the file may contain - nothing except a line of comment (for example "# empty"). - -- If some filters use protocol names (like tcp or udp) you have to provide a - +/etc/protocols+ file. - -- If some filters use service names (like ssh or http) you have to provide a - +/etc/services+ file. - -- Create a rule file (normally +/etc/pf.conf+). See the FreeBSD manual for the - syntax. - -- Load the rule file using the pfctl command and enable pf. Please note that the - pfctl command needs a lot of stack. You should use at least - RTEMS_MINIMUM_STACK_SIZE + 8192 Bytes of stack. An example initialisation can - look like follows: - ----- - int exit_code; - char *params[] = { - "pfctl", - "-f", - "/etc/pf.conf", - "-e", - NULL - }; - - exit_code = rtems_bsd_command_pfctl(ARGC(params), params); - assert(exit_code == EXIT_SUCCSESS); ----- - -=== Known restrictions === - -- Currently PF on RTEMS always uses the configuration for memory restricted - systems (on FreeBSD that means systems with less than 100 MB RAM). This is - fixed in +pfctl_init_options()+. - -== Wireless Network (WLAN) == - -The libbsd provides a basic support for WLAN. Note that currently this support -is still in an early state. The WLAN support is _not_ enabled in the default -buildset. You have to configure libbsd with the -`--buildset=buildset/everything.ini` to enable that feature. - -The following gives a rough overview over the necessary steps to connect to an -encrypted network with an RTL8188EU based WiFi dongle: - -- Reference all necessary module for your BSP. For some BSPs this is already - done in the nexus-devices.h: - ----- - SYSINIT_MODULE_REFERENCE(wlan_ratectl_none); - SYSINIT_MODULE_REFERENCE(wlan_sta); - SYSINIT_MODULE_REFERENCE(wlan_amrr); - SYSINIT_MODULE_REFERENCE(wlan_wep); - SYSINIT_MODULE_REFERENCE(wlan_tkip); - SYSINIT_MODULE_REFERENCE(wlan_ccmp); - SYSINIT_DRIVER_REFERENCE(rtwn_usb, uhub); - SYSINIT_REFERENCE(rtwn_rtl8188eufw); ----- - -- Create your wlan device using ifconfig: - +ifconfig wlan0 create wlandev rtwn0 up+ - -- Start a wpa_supplicant instance for that device: - + wpa_supplicant_fork -Dbsd -iwlan0 -c/media/mmcsd-0-0/wpa_supplicant.conf+ - -Note that the wpa_supplicant will only be active till the device goes down. A -workaround is to just restart it every time it exits. - -=== Known restrictions === - -- The network interface (e.g. wlan0) is currently not automatically created. It - would be nice, if some service would create it as soon as for example a USB - device is connected. In FreeBSD the names are assigned via rc.conf with lines - like +wlans_rtwn0="wlan0"+. - -- wpa_supplicant hast to be started after the device is created. It has to be - restarted every time the connection goes down. Instead of this behaviour, - there should be some service that starts and restarts wpa_supplicant - automatically if a interface is ready. Probably the dhcpcd hooks could be used - for that. - -- The current wpa_supplicant implementation is protected with a lock so it can't - be started more than one time. If multiple interface should be used, all have - to be handled by that single instance. That makes it hard to add interfaces - dynamically. wpa_supplicant should be reviewed thoroughly whether multiple - instances could be started in parallel. - -- The control interface of wpa_supplicant most likely doesn't work. The wpa_cli - application is not ported. - -== IPSec == - -The IPSec support is optional in libbsd. It is disabled in the default build -set. Please make sure to use a build set with +netipsec = on+. - -To use IPSec the following configuration is necessary: - ----- -SYSINIT_MODULE_REFERENCE(if_gif); -SYSINIT_MODULE_REFERENCE(cryptodev); -RTEMS_BSD_RC_CONF_SYSINT(rc_conf_ipsec) -RTEMS_BSD_DEFINE_NEXUS_DEVICE(cryptosoft, 0, 0, NULL); ----- - -Alternatively you can use the `RTEMS_BSD_CONFIG_IPSEC` which also includes the -rc.conf support for ipsec. It's still necessary to include a crypto device in -your config (`cryptosoft` in the above sample). - -The necessary initialization steps for a IPSec connection are similar to the -steps on a FreeBSD-System. The example assumes the following setup: - -- RTEMS external IP: 192.168.10.1/24 -- RTEMS internal IP: 10.10.1.1/24 -- remote external IP: 192.168.10.10/24 -- remote internal IP: 172.24.0.1/24 -- shared key: "mysecretkey" - -With this the following steps are necessary: - -- Create a gif0 device: - ----- -SHLL [/] # ifconfig gif0 create ----- - -- Configure the gif0 device: - ----- -SHLL [/] # ifconfig gif0 10.10.1.1 172.24.0.1 -SHLL [/] # ifconfig gif0 tunnel 192.168.10.1 192.168.10.10 ----- - -- Add a route to the remote net via the remote IP: - ----- -SHLL [/] # route add 172.24.0.0/24 172.24.0.1 ----- - -- Call `setkey` with a correct rule set: - ----- -SHLL [/] # cat /etc/setkey.conf -flush; -spdflush; -spdadd 10.10.1.0/24 172.24.0.0/24 any -P out ipsec esp/tunnel/192.168.10.1-192.168.10.10/use; -spdadd 172.24.0.0/24 10.10.1.0/24 any -P in ipsec esp/tunnel/192.168.10.10-192.168.10.1/use; -SHLL [/] # setkey -f /etc/setkey.conf ----- - -- Start a ike-daemon (racoon) with a correct configuration. ----- -SHLL [/] # cat /etc/racoon.conf -path pre_shared_key "/etc/racoon_psk.txt"; -log info; - -padding # options are not to be changed -{ - maximum_length 20; - randomize off; - strict_check off; - exclusive_tail off; -} - -listen # address [port] that racoon will listen on -{ - isakmp 192.168.10.1[500]; -} - -remote 192.168.10.10 [500] -{ - exchange_mode main; - my_identifier address 192.168.10.1; - peers_identifier address 192.168.10.10; - proposal_check obey; - - proposal { - encryption_algorithm 3des; - hash_algorithm md5; - authentication_method pre_shared_key; - lifetime time 3600 sec; - dh_group 2; - } -} - -sainfo (address 10.10.1.0/24 any address 172.24.0.0/24 any) -{ - pfs_group 2; - lifetime time 28800 sec; - encryption_algorithm 3des; - authentication_algorithm hmac_md5; - compression_algorithm deflate; -} -SHLL [/] # cat /etc/racoon_psk.txt -192.168.10.10 mysecretkey -SHLL [/] # racoon -F -f /etc/racoon.conf ----- - -All commands can be called via the respective API functions. For racoon there is -a `rtems_bsd_racoon_daemon()` function that forks of racoon as a task. - -Alternatively IPSec can also be configured via rc.conf entries: - ----- -cloned_interfaces="gif0" -ifconfig_gif0="10.10.1.1 172.24.0.1 tunnel 192.168.10.1 192.168.10.10" -ike_enable="YES" -ike_program="racoon" -ike_flags="-F -f /etc/racoon.conf" -ike_priority="250" - -ipsec_enable="YES" -ipsec_file="/etc/setkey.conf" ----- - -ATTENTION: It is possible that the first packets slip through the tunnel without -encryption (true for FreeBSD as well as RTEMS). You might want to set up a -firewall rule to prevent that. - -== Problems to report to FreeBSD == - -The MMAP_NOT_AVAILABLE define is inverted on its usage. When it is -defined the mmap method is called. Additionally, it is not used -thoroughly. It is not used in the unmap portion of the source. -The file rec_open.c uses the define MMAP_NOT_AVAILABLE to wrap -the call to mmap and file rec_close.c uses the munmap method. |