freebsd-nq/sys/xen/interface/io/libxenvchan.h
Roger Pau Monné 1a52c10530 Update Xen headers from 4.2 to 4.6
Pull the latest headers for Xen which allow us to add support for ARM and
use new features in FreeBSD.

This is a verbatim copy of the xen/include/public so every headers which
don't exits anymore in the Xen repositories have been dropped.

Note the interface version hasn't been bumped, it will be done in a
follow-up. Although, it requires fix in the code to get it compiled:

 - sys/xen/xen_intr.h: evtchn_port_t is already defined in the headers so
   drop it.

 - {amd64,i386}/include/intr_machdep.h: NR_EVENT_CHANNELS now depends on
   xen/interface/event_channel.h, so include it.

 - {amd64,i386}/{amd64,i386}/support.S: It's not neccessary to include
   machine/intr_machdep.h. This is also fixing build compilation with the
   new headers.

 - dev/xen/blkfront/blkfront.c: The typedef for blkif_request_segmenthas
   been dropped. So directly use struct blkif_request_segment

Finally, modify xen/interface/xen-compat.h to throw a preprocessing error if
__XEN_INTERFACE_VERSION__ is not set. This is allow us to catch any file
where xen/xen-os.h is not correctly included.

Submitted by:		Julien Grall <julien.grall@citrix.com>
Reviewed by:		royger
Differential Revision:	https://reviews.freebsd.org/D3805
Sponsored by:		Citrix Systems R&D
2015-10-06 11:29:44 +00:00

97 lines
3.3 KiB
C

/**
* @file
* @section AUTHORS
*
* Copyright (C) 2010 Rafal Wojtczuk <rafal@invisiblethingslab.com>
*
* Authors:
* Rafal Wojtczuk <rafal@invisiblethingslab.com>
* Daniel De Graaf <dgdegra@tycho.nsa.gov>
*
* @section LICENSE
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; If not, see <http://www.gnu.org/licenses/>.
*
* @section DESCRIPTION
*
* Originally borrowed from the Qubes OS Project, http://www.qubes-os.org,
* this code has been substantially rewritten to use the gntdev and gntalloc
* devices instead of raw MFNs and map_foreign_range.
*
* This is a library for inter-domain communication. A standard Xen ring
* buffer is used, with a datagram-based interface built on top. The grant
* reference and event channels are shared in XenStore under a user-specified
* path.
*
* The ring.h macros define an asymmetric interface to a shared data structure
* that assumes all rings reside in a single contiguous memory space. This is
* not suitable for vchan because the interface to the ring is symmetric except
* for the setup. Unlike the producer-consumer rings defined in ring.h, the
* size of the rings used in vchan are determined at execution time instead of
* compile time, so the macros in ring.h cannot be used to access the rings.
*/
#include <stdint.h>
#include <sys/types.h>
struct ring_shared {
uint32_t cons, prod;
};
#define VCHAN_NOTIFY_WRITE 0x1
#define VCHAN_NOTIFY_READ 0x2
/**
* vchan_interface: primary shared data structure
*/
struct vchan_interface {
/**
* Standard consumer/producer interface, one pair per buffer
* left is client write, server read
* right is client read, server write
*/
struct ring_shared left, right;
/**
* size of the rings, which determines their location
* 10 - at offset 1024 in ring's page
* 11 - at offset 2048 in ring's page
* 12+ - uses 2^(N-12) grants to describe the multi-page ring
* These should remain constant once the page is shared.
* Only one of the two orders can be 10 (or 11).
*/
uint16_t left_order, right_order;
/**
* Shutdown detection:
* 0: client (or server) has exited
* 1: client (or server) is connected
* 2: client has not yet connected
*/
uint8_t cli_live, srv_live;
/**
* Notification bits:
* VCHAN_NOTIFY_WRITE: send notify when data is written
* VCHAN_NOTIFY_READ: send notify when data is read (consumed)
* cli_notify is used for the client to inform the server of its action
*/
uint8_t cli_notify, srv_notify;
/**
* Grant list: ordering is left, right. Must not extend into actual ring
* or grow beyond the end of the initial shared page.
* These should remain constant once the page is shared, to allow
* for possible remapping by a client that restarts.
*/
uint32_t grants[0];
};