Files
xen/tools/libxc/xc_mem_event.c
T
Tim Deegan 770d1e858d Use a reserved pfn in the guest address space to store mem event rings
This solves a long-standing issue in which the pages backing these rings were
pages belonging to dom0 user-space processes. Thus, if the process would die
unexpectedly, Xen would keep posting events to a page now belonging to some
other process.

We update all API-consumers in tree (xenpaging and xen-access).

This is an API/ABI change, so please speak up if it breaks your accumptions.

The patch touches tools, hypervisor x86/hvm bits, and hypervisor x86/mm bits.

Signed-off-by: Andres Lagar-Cavilla <andres@lagarcavilla.org>
Acked-by: Tim Deegan <tim@xen.org>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Committed-by: Tim Deegan <tim@xen.org>
2012-03-08 16:40:05 +00:00

59 lines
1.8 KiB
C

/******************************************************************************
*
* xc_mem_event.c
*
* Interface to low-level memory event functionality.
*
* Copyright (c) 2009 Citrix Systems, Inc. (Patrick Colp)
*
* 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, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "xc_private.h"
int xc_mem_event_control(xc_interface *xch, domid_t domain_id, unsigned int op,
unsigned int mode, uint32_t *port)
{
DECLARE_DOMCTL;
int rc;
domctl.cmd = XEN_DOMCTL_mem_event_op;
domctl.domain = domain_id;
domctl.u.mem_event_op.op = op;
domctl.u.mem_event_op.mode = mode;
rc = do_domctl(xch, &domctl);
if ( !rc && port )
*port = domctl.u.mem_event_op.port;
return rc;
}
int xc_mem_event_memop(xc_interface *xch, domid_t domain_id,
unsigned int op, unsigned int mode,
uint64_t gfn, void *buffer)
{
xen_mem_event_op_t meo;
memset(&meo, 0, sizeof(meo));
meo.op = op;
meo.domain = domain_id;
meo.gfn = gfn;
meo.buffer = (unsigned long) buffer;
return do_memory_op(xch, mode, &meo, sizeof(meo));
}