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

 * multicall.c

 */

#include <xen/types.h>

#include <xen/lib.h>

#include <xen/mm.h>

#include <xen/sched.h>

#include <xen/event.h>

#include <xen/multicall.h>

#include <xen/guest_access.h>

#include <xen/perfc.h>

#include <xen/trace.h>

#include <asm/current.h>

#include <asm/hardirq.h>

#ifndef COMPAT

typedef long ret_t;

#define xlat_multicall_entry(mcs)

static void __trace_multicall_call(multicall_entry_t *call)

{

    __trace_hypercall(TRC_PV_HYPERCALL_SUBCALL, call->op, call->args);

}

#endif

static void trace_multicall_call(multicall_entry_t *call)

{

    if ( !tb_init_done )

        return;

    __trace_multicall_call(call);

}

ret_t

do_multicall(

    XEN_GUEST_HANDLE_PARAM(multicall_entry_t) call_list, uint32_t nr_calls)

{

    struct vcpu *curr = current;

    struct mc_state *mcs = &curr->mc_state;

    uint32_t         i;

    int              rc = 0;

    enum mc_disposition disp = mc_continue;

    if ( unlikely(__test_and_set_bit(_MCSF_in_multicall, &mcs->flags)) )

    {

        gdprintk(XENLOG_INFO, "Multicall reentry is disallowed.\n");

        return -EINVAL;

    }

    if ( unlikely(!guest_handle_okay(call_list, nr_calls)) )

        rc = -EFAULT;

    for ( i = 0; !rc && disp == mc_continue && i < nr_calls; i++ )

    {

        if ( i && hypercall_preempt_check() )

            goto preempted;

        if ( unlikely(__copy_from_guest(&mcs->call, call_list, 1)) )

        {

            rc = -EFAULT;

            break;

        }

        trace_multicall_call(&mcs->call);

        disp = arch_do_multicall_call(mcs);

#ifndef NDEBUG

        {

            /*

             * Deliberately corrupt the contents of the multicall structure.

             * The caller must depend only on the 'result' field on return.

             */

            struct multicall_entry corrupt;

            memset(&corrupt, 0xAA, sizeof(corrupt));

            (void)__copy_to_guest(call_list, &corrupt, 1);

        }

#endif

        if ( unlikely(disp == mc_exit) )

        {

            if ( __copy_field_to_guest(call_list, &mcs->call, result) )

                /* nothing, best effort only */;

            rc = mcs->call.result;

        }

        else if ( unlikely(__copy_field_to_guest(call_list, &mcs->call,

                                                 result)) )

            rc = -EFAULT;

        else if ( curr->hcall_preempted )

        {

            /* Translate sub-call continuation to guest layout */

            xlat_multicall_entry(mcs);

            /* Copy the sub-call continuation. */

            if ( likely(!__copy_to_guest(call_list, &mcs->call, 1)) )

                goto preempted;

            else

                hypercall_cancel_continuation(curr);

            rc = -EFAULT;

        }

        else

            guest_handle_add_offset(call_list, 1);

    }

    if ( unlikely(disp == mc_preempt) && i < nr_calls )

        goto preempted;

    perfc_incr(calls_to_multicall);

    perfc_add(calls_from_multicall, i);

    mcs->flags = 0;

    return rc;

 preempted:

    perfc_add(calls_from_multicall, i);

    mcs->flags = 0;

    return hypercall_create_continuation(

        __HYPERVISOR_multicall, "hi", call_list, nr_calls-i);

}

Unexecuted instantiation: do_multicall

Unexecuted instantiation: compat_multicall

/*

 * Local variables:

 * mode: C

 * c-file-style: "BSD"

 * c-basic-offset: 4

 * tab-width: 4

 * indent-tabs-mode: nil

 * End:

 */