linux-imx

/*

 * VMware VMCI Driver

 *

 * Copyright (C) 2012 VMware, Inc. All rights reserved.

 *

 * 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 version 2 and no 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.

 */

​

#include <linux/vmw_vmci_defs.h>

#include <linux/vmw_vmci_api.h>

​

#include "vmci_context.h"

#include "vmci_driver.h"

#include "vmci_route.h"

​

/*

 * Make a routing decision for the given source and destination handles.

 * This will try to determine the route using the handles and the available

 * devices.  Will set the source context if it is invalid.

 */

int vmci_route(struct vmci_handle *src,

           const struct vmci_handle *dst,

           bool from_guest,

           enum vmci_route *route)

{

    bool has_host_device = vmci_host_code_active();

    bool has_guest_device = vmci_guest_code_active();

​

    *route = VMCI_ROUTE_NONE;

​

    /*

     * "from_guest" is only ever set to true by

     * IOCTL_VMCI_DATAGRAM_SEND (or by the vmkernel equivalent),

     * which comes from the VMX, so we know it is coming from a

     * guest.

     *

     * To avoid inconsistencies, test these once.  We will test

     * them again when we do the actual send to ensure that we do

     * not touch a non-existent device.

     */

​

    /* Must have a valid destination context. */

    if (VMCI_INVALID_ID == dst->context)

        return VMCI_ERROR_INVALID_ARGS;

​

    /* Anywhere to hypervisor. */

    if (VMCI_HYPERVISOR_CONTEXT_ID == dst->context) {

​

        /*

         * If this message already came from a guest then we

         * cannot send it to the hypervisor.  It must come

         * from a local client.

         */

        if (from_guest)

            return VMCI_ERROR_DST_UNREACHABLE;

​