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diff --git a/Documentation/linux_tv/media/dvb/net.rst b/Documentation/linux_tv/media/dvb/net.rst new file mode 100644 index 0000000..040ffc7 --- /dev/null +++ b/Documentation/linux_tv/media/dvb/net.rst @@ -0,0 +1,219 @@ +.. -*- coding: utf-8; mode: rst -*- + +.. _net: + +############### +DVB Network API +############### +The DVB net device controls the mapping of data packages that are part +of a transport stream to be mapped into a virtual network interface, +visible through the standard Linux network protocol stack. + +Currently, two encapsulations are supported: + +- `Multi Protocol Encapsulation (MPE) <http://en.wikipedia.org/wiki/Multiprotocol_Encapsulation>`__ + +- `Ultra Lightweight Encapsulation (ULE) <http://en.wikipedia.org/wiki/Unidirectional_Lightweight_Encapsulation>`__ + +In order to create the Linux virtual network interfaces, an application +needs to tell to the Kernel what are the PIDs and the encapsulation +types that are present on the transport stream. This is done through +``/dev/dvb/adapter?/net?`` device node. The data will be available via +virtual ``dvb?_?`` network interfaces, and will be controlled/routed via +the standard ip tools (like ip, route, netstat, ifconfig, etc). + +Data types and and ioctl definitions are defined via ``linux/dvb/net.h`` +header. + + +.. _net_fcalls: + +###################### +DVB net Function Calls +###################### + +.. _NET_ADD_IF: + +**************** +ioctl NET_ADD_IF +**************** + +*man NET_ADD_IF(2)* + +Creates a new network interface for a given Packet ID. + + +Synopsis +======== + +.. c:function:: int ioctl( int fd, int request, struct dvb_net_if *net_if ) + +Arguments +========= + +``fd`` + File descriptor returned by :ref:`open() <frontend_f_open>`. + +``request`` + FE_SET_TONE + +``net_if`` + pointer to struct :ref:`dvb_net_if <dvb-net-if>` + + +Description +=========== + +The NET_ADD_IF ioctl system call selects the Packet ID (PID) that +contains a TCP/IP traffic, the type of encapsulation to be used (MPE or +ULE) and the interface number for the new interface to be created. When +the system call successfully returns, a new virtual network interface is +created. + +The struct :ref:`dvb_net_if <dvb-net-if>`::ifnum field will be +filled with the number of the created interface. + +RETURN VALUE + +On success 0 is returned, on error -1 and the ``errno`` variable is set +appropriately. The generic error codes are described at the +:ref:`Generic Error Codes <gen-errors>` chapter. + + +.. _dvb-net-if-t: + +struct dvb_net_if description +============================= + + +.. _dvb-net-if: + +.. flat-table:: struct dvb_net_if + :header-rows: 1 + :stub-columns: 0 + + + - .. row 1 + + - ID + + - Description + + - .. row 2 + + - pid + + - Packet ID (PID) of the MPEG-TS that contains data + + - .. row 3 + + - ifnum + + - number of the DVB interface. + + - .. row 4 + + - feedtype + + - Encapsulation type of the feed. It can be: + ``DVB_NET_FEEDTYPE_MPE`` for MPE encoding or + ``DVB_NET_FEEDTYPE_ULE`` for ULE encoding. + + + +.. _NET_REMOVE_IF: + +******************* +ioctl NET_REMOVE_IF +******************* + +*man NET_REMOVE_IF(2)* + +Removes a network interface. + + +Synopsis +======== + +.. c:function:: int ioctl( int fd, int request, int ifnum ) + +Arguments +========= + +``fd`` + File descriptor returned by :ref:`open() <frontend_f_open>`. + +``request`` + FE_SET_TONE + +``net_if`` + number of the interface to be removed + + +Description +=========== + +The NET_REMOVE_IF ioctl deletes an interface previously created via +:ref:`NET_ADD_IF <net>`. + +RETURN VALUE + +On success 0 is returned, on error -1 and the ``errno`` variable is set +appropriately. The generic error codes are described at the +:ref:`Generic Error Codes <gen-errors>` chapter. + + +.. _NET_GET_IF: + +**************** +ioctl NET_GET_IF +**************** + +*man NET_GET_IF(2)* + +Read the configuration data of an interface created via +:ref:`NET_ADD_IF <net>`. + + +Synopsis +======== + +.. c:function:: int ioctl( int fd, int request, struct dvb_net_if *net_if ) + +Arguments +========= + +``fd`` + File descriptor returned by :ref:`open() <frontend_f_open>`. + +``request`` + FE_SET_TONE + +``net_if`` + pointer to struct :ref:`dvb_net_if <dvb-net-if>` + + +Description +=========== + +The NET_GET_IF ioctl uses the interface number given by the struct +:ref:`dvb_net_if <dvb-net-if>`::ifnum field and fills the content of +struct :ref:`dvb_net_if <dvb-net-if>` with the packet ID and +encapsulation type used on such interface. If the interface was not +created yet with :ref:`NET_ADD_IF <net>`, it will return -1 and fill +the ``errno`` with ``EINVAL`` error code. + +RETURN VALUE + +On success 0 is returned, on error -1 and the ``errno`` variable is set +appropriately. The generic error codes are described at the +:ref:`Generic Error Codes <gen-errors>` chapter. + + +.. ------------------------------------------------------------------------------ +.. This file was automatically converted from DocBook-XML with the dbxml +.. library (https://github.com/return42/sphkerneldoc). The origin XML comes +.. from the linux kernel, refer to: +.. +.. * https://github.com/torvalds/linux/tree/master/Documentation/DocBook +.. ------------------------------------------------------------------------------ |
