/******************************************************************************

 * mem_access.c

 *

 * Memory access support.

 *

 * Copyright (c) 2011 Virtuata, Inc.

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License as published by

 * the Free Software Foundation; either version 2 of the License, or

 * (at your option) any later version.

 *

 * This program 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 General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program; If not, see <http://www.gnu.org/licenses/>.

 */

#include <xen/sched.h>

#include <xen/guest_access.h>

#include <xen/hypercall.h>

#include <xen/vm_event.h>

#include <xen/mem_access.h>

#include <public/memory.h>

#include <xsm/xsm.h>

int mem_access_memop(unsigned long cmd,

                     XEN_GUEST_HANDLE_PARAM(xen_mem_access_op_t) arg)

{

    unsigned long start_iter = cmd & ~MEMOP_CMD_MASK;

    long rc;

    xen_mem_access_op_t mao;

    struct domain *d;

    if ( copy_from_guest(&mao, arg, 1) )

        return -EFAULT;

    rc = rcu_lock_live_remote_domain_by_id(mao.domid, &d);

    if ( rc )

        return rc;

    rc = -EINVAL;

    if ( !p2m_mem_access_sanity_check(d) )

        goto out;

    rc = xsm_mem_access(XSM_DM_PRIV, d);

    if ( rc )

        goto out;

    rc = -ENODEV;

    if ( unlikely(!vm_event_check_ring(d->vm_event_monitor)) )

        goto out;

    switch ( mao.op )

    {

    case XENMEM_access_op_set_access:

        rc = -EINVAL;

        if ( (mao.pfn != ~0ull) &&

             (mao.nr < start_iter ||

              ((mao.pfn + mao.nr - 1) < mao.pfn) ||

              ((mao.pfn + mao.nr - 1) > domain_get_maximum_gpfn(d))) )

            break;

        rc = p2m_set_mem_access(d, _gfn(mao.pfn), mao.nr, start_iter,

                                MEMOP_CMD_MASK, mao.access, 0);

        if ( rc > 0 )

        {

            ASSERT(!(rc & MEMOP_CMD_MASK));

            rc = hypercall_create_continuation(__HYPERVISOR_memory_op, "lh",

                                               XENMEM_access_op | rc, arg);

        }

        break;

    case XENMEM_access_op_set_access_multi:

        rc = p2m_set_mem_access_multi(d, mao.pfn_list, mao.access_list, mao.nr,

                                      start_iter, MEMOP_CMD_MASK, 0);

        if ( rc > 0 )

        {

            ASSERT(!(rc & MEMOP_CMD_MASK));

            rc = hypercall_create_continuation(__HYPERVISOR_memory_op, "lh",

                                               XENMEM_access_op | rc, arg);

        }

        break;

    case XENMEM_access_op_get_access:

    {

        xenmem_access_t access;

        rc = -ENOSYS;

        if ( unlikely(start_iter) )

            break;

        rc = -EINVAL;

        if ( (mao.pfn > domain_get_maximum_gpfn(d)) && mao.pfn != ~0ull )

            break;

        rc = p2m_get_mem_access(d, _gfn(mao.pfn), &access);

        if ( rc != 0 )

            break;

        mao.access = access;

        rc = __copy_field_to_guest(arg, &mao, access) ? -EFAULT : 0;

        break;

    }

    default:

        rc = -ENOSYS;

        break;

    }

 out:

    rcu_unlock_domain(d);

    return rc;

}

/*

 * Local variables:

 * mode: C

 * c-file-style: "BSD"

 * c-basic-offset: 4

 * indent-tabs-mode: nil

 * End:

 */