Exemplo n.º 1
0
static int vtimer_emulate_cp64(struct cpu_user_regs *regs, union hsr hsr)
{
    struct hsr_cp64 cp64 = hsr.cp64;
    uint32_t *r1 = (uint32_t *)select_user_reg(regs, cp64.reg1);
    uint32_t *r2 = (uint32_t *)select_user_reg(regs, cp64.reg2);
    uint64_t x = (uint64_t)(*r1) | ((uint64_t)(*r2) << 32);

    if ( cp64.read )
        perfc_incr(vtimer_cp64_reads);
    else
        perfc_incr(vtimer_cp64_writes);

    switch ( hsr.bits & HSR_CP64_REGS_MASK )
    {
    case HSR_CPREG64(CNTP_CVAL):
        if ( !vtimer_cntp_cval(regs, &x, cp64.read) )
            return 0;
        break;

    default:
        return 0;
    }

    if ( cp64.read )
    {
        *r1 = (uint32_t)(x & 0xffffffff);
        *r2 = (uint32_t)(x >> 32);
    }
Exemplo n.º 2
0
static void phys_timer_expired(void *data)
{
    struct vtimer *t = data;
    t->ctl |= CNTx_CTL_PENDING;
    if ( !(t->ctl & CNTx_CTL_MASK) )
    {
        perfc_incr(vtimer_phys_inject);
        vgic_vcpu_inject_irq(t->v, t->irq);
    }
    else
        perfc_incr(vtimer_phys_masked);
}
Exemplo n.º 3
0
static void virt_timer_expired(void *data)
{
    struct vtimer *t = data;
    t->ctl |= CNTx_CTL_MASK;
    vgic_vcpu_inject_irq(t->v, t->irq);
    perfc_incr(vtimer_virt_inject);
}
Exemplo n.º 4
0
int rdmsr_viridian_regs(uint32_t idx, uint64_t *val)
{
    struct vcpu *v = current;
    struct domain *d = v->domain;
    
    if ( !is_viridian_domain(d) )
        return 0;

    switch ( idx )
    {
    case VIRIDIAN_MSR_GUEST_OS_ID:
        perfc_incr(mshv_rdmsr_osid);
        *val = d->arch.hvm_domain.viridian.guest_os_id.raw;
        break;

    case VIRIDIAN_MSR_HYPERCALL:
        perfc_incr(mshv_rdmsr_hc_page);
        *val = d->arch.hvm_domain.viridian.hypercall_gpa.raw;
        break;

    case VIRIDIAN_MSR_VP_INDEX:
        perfc_incr(mshv_rdmsr_vp_index);
        *val = v->vcpu_id;
        break;

    case VIRIDIAN_MSR_TSC_FREQUENCY:
        perfc_incr(mshv_rdmsr_tsc_frequency);
        *val = (uint64_t)d->arch.tsc_khz * 1000ull;
        break;

    case VIRIDIAN_MSR_APIC_FREQUENCY:
        perfc_incr(mshv_rdmsr_apic_frequency);
        *val = 1000000000ull / APIC_BUS_CYCLE_NS;
        break;

    case VIRIDIAN_MSR_ICR:
        perfc_incr(mshv_rdmsr_icr);
        *val = (((uint64_t)vlapic_get_reg(vcpu_vlapic(v), APIC_ICR2) << 32) |
                vlapic_get_reg(vcpu_vlapic(v), APIC_ICR));
        break;

    case VIRIDIAN_MSR_TPR:
        perfc_incr(mshv_rdmsr_tpr);
        *val = vlapic_get_reg(vcpu_vlapic(v), APIC_TASKPRI);
        break;

    case VIRIDIAN_MSR_APIC_ASSIST:
        perfc_incr(mshv_rdmsr_apic_msr);
        *val = v->arch.hvm_vcpu.viridian.apic_assist.raw;
        break;

    default:
        return 0;
    }

    return 1;
}
Exemplo n.º 5
0
Arquivo: realmode.c Projeto: CPFL/xen
static void realmode_emulate_one(struct hvm_emulate_ctxt *hvmemul_ctxt)
{
    struct vcpu *curr = current;
    int rc;

    perfc_incr(realmode_emulations);

    rc = hvm_emulate_one(hvmemul_ctxt);

    if ( rc == X86EMUL_UNHANDLEABLE )
    {
        gdprintk(XENLOG_ERR, "Failed to emulate insn.\n");
        goto fail;
    }

    if ( rc == X86EMUL_EXCEPTION )
    {
        if ( !hvmemul_ctxt->exn_pending )
        {
            unsigned long intr_info;

            __vmread(VM_ENTRY_INTR_INFO, &intr_info);
            __vmwrite(VM_ENTRY_INTR_INFO, 0);
            if ( !(intr_info & INTR_INFO_VALID_MASK) )
            {
                gdprintk(XENLOG_ERR, "Exception pending but no info.\n");
                goto fail;
            }
            hvmemul_ctxt->trap.vector = (uint8_t)intr_info;
            hvmemul_ctxt->trap.insn_len = 0;
        }

        if ( unlikely(curr->domain->debugger_attached) &&
             ((hvmemul_ctxt->trap.vector == TRAP_debug) ||
              (hvmemul_ctxt->trap.vector == TRAP_int3)) )
        {
            domain_pause_for_debugger();
        }
        else if ( curr->arch.hvm_vcpu.guest_cr[0] & X86_CR0_PE )
        {
            gdprintk(XENLOG_ERR, "Exception %02x in protected mode.\n",
                     hvmemul_ctxt->trap.vector);
            goto fail;
        }
        else
        {
            realmode_deliver_exception(
                hvmemul_ctxt->trap.vector,
                hvmemul_ctxt->trap.insn_len,
                hvmemul_ctxt);
        }
    }

    return;

 fail:
    hvm_dump_emulation_state(XENLOG_G_ERR "Real-mode", hvmemul_ctxt);
    domain_crash(curr->domain);
}
Exemplo n.º 6
0
fastcall void smp_apic_timer_interrupt(struct cpu_user_regs * regs)
{
    struct cpu_user_regs *old_regs = set_irq_regs(regs);
    ack_APIC_irq();
    perfc_incr(apic_timer);
    raise_softirq(TIMER_SOFTIRQ);
    set_irq_regs(old_regs);
}
Exemplo n.º 7
0
Arquivo: vtimer.c Projeto: Xilinx/xen
static bool vtimer_emulate_cp64(struct cpu_user_regs *regs, union hsr hsr)
{
    struct hsr_cp64 cp64 = hsr.cp64;

    if ( cp64.read )
        perfc_incr(vtimer_cp64_reads);
    else
        perfc_incr(vtimer_cp64_writes);

    switch ( hsr.bits & HSR_CP64_REGS_MASK )
    {
    case HSR_CPREG64(CNTP_CVAL):
        return vreg_emulate_cp64(regs, hsr, vtimer_cntp_cval);

    default:
        return false;
    }
}
Exemplo n.º 8
0
void invalidate_interrupt(struct cpu_user_regs *regs)
{
    ack_APIC_irq();
    perfc_incr(ipis);
    if ( !__sync_local_execstate() ||
         (flush_flags & (FLUSH_TLB_GLOBAL | FLUSH_CACHE)) )
        flush_area_local(flush_va, flush_flags);
    cpumask_clear_cpu(smp_processor_id(), &flush_cpumask);
}
Exemplo n.º 9
0
int rdmsr_viridian_regs(uint32_t idx, uint64_t *val)
{
    struct vcpu *v = current;
    
    if ( !is_viridian_domain(v->domain) )
        return 0;

    switch ( idx )
    {
    case VIRIDIAN_MSR_GUEST_OS_ID:
        perfc_incr(mshv_rdmsr_osid);
        *val = v->domain->arch.hvm_domain.viridian.guest_os_id.raw;
        break;

    case VIRIDIAN_MSR_HYPERCALL:
        perfc_incr(mshv_rdmsr_hc_page);
        *val = v->domain->arch.hvm_domain.viridian.hypercall_gpa.raw;
        break;

    case VIRIDIAN_MSR_VP_INDEX:
        perfc_incr(mshv_rdmsr_vp_index);
        *val = v->vcpu_id;
        break;

    case VIRIDIAN_MSR_ICR:
        perfc_incr(mshv_rdmsr_icr);
        *val = (((uint64_t)vlapic_get_reg(vcpu_vlapic(v), APIC_ICR2) << 32) |
                vlapic_get_reg(vcpu_vlapic(v), APIC_ICR));
        break;

    case VIRIDIAN_MSR_TPR:
        perfc_incr(mshv_rdmsr_tpr);
        *val = vlapic_get_reg(vcpu_vlapic(v), APIC_TASKPRI);
        break;

    default:
        return 0;
    }

    return 1;
}
Exemplo n.º 10
0
Arquivo: vtimer.c Projeto: Xilinx/xen
static bool vtimer_emulate_cp32(struct cpu_user_regs *regs, union hsr hsr)
{
    struct hsr_cp32 cp32 = hsr.cp32;

    if ( cp32.read )
        perfc_incr(vtimer_cp32_reads);
    else
        perfc_incr(vtimer_cp32_writes);

    switch ( hsr.bits & HSR_CP32_REGS_MASK )
    {
    case HSR_CPREG32(CNTP_CTL):
        return vreg_emulate_cp32(regs, hsr, vtimer_cntp_ctl);

    case HSR_CPREG32(CNTP_TVAL):
        return vreg_emulate_cp32(regs, hsr, vtimer_cntp_tval);

    default:
        return false;
    }
}
Exemplo n.º 11
0
Arquivo: vtimer.c Projeto: 0day-ci/xen
static int vtimer_emulate_cp32(struct cpu_user_regs *regs, union hsr hsr)
{
    struct hsr_cp32 cp32 = hsr.cp32;
    /*
     * Initialize to zero to avoid leaking data if there is an
     * implementation error in the emulation (such as not correctly
     * setting r).
     */
    uint32_t r = 0;
    int res;


    if ( cp32.read )
        perfc_incr(vtimer_cp32_reads);
    else
        perfc_incr(vtimer_cp32_writes);

    if ( !cp32.read )
        r = get_user_reg(regs, cp32.reg);

    switch ( hsr.bits & HSR_CP32_REGS_MASK )
    {
    case HSR_CPREG32(CNTP_CTL):
        res = vtimer_cntp_ctl(regs, &r, cp32.read);
        break;

    case HSR_CPREG32(CNTP_TVAL):
        res = vtimer_cntp_tval(regs, &r, cp32.read);
        break;

    default:
        return 0;
    }

    if ( res && cp32.read )
        set_user_reg(regs, cp32.reg, r);

    return res;
}
Exemplo n.º 12
0
/* Handle the firing timer */
static void timer_interrupt(int irq, void *dev_id, struct cpu_user_regs *regs)
{
    if ( irq == (timer_irq[TIMER_HYP_PPI]) &&
            READ_SYSREG32(CNTHP_CTL_EL2) & CNTx_CTL_PENDING )
    {
        perfc_incr(hyp_timer_irqs);
        /* Signal the generic timer code to do its work */
        raise_softirq(TIMER_SOFTIRQ);
        /* Disable the timer to avoid more interrupts */
        WRITE_SYSREG32(0, CNTHP_CTL_EL2);
    }

    if ( irq == (timer_irq[TIMER_PHYS_NONSECURE_PPI]) &&
            READ_SYSREG32(CNTP_CTL_EL0) & CNTx_CTL_PENDING )
    {
        perfc_incr(phys_timer_irqs);
        /* Signal the generic timer code to do its work */
        raise_softirq(TIMER_SOFTIRQ);
        /* Disable the timer to avoid more interrupts */
        WRITE_SYSREG32(0, CNTP_CTL_EL0);
    }
}
Exemplo n.º 13
0
static int vtimer_emulate_cp32(struct cpu_user_regs *regs, union hsr hsr)
{
    struct hsr_cp32 cp32 = hsr.cp32;
    uint32_t *r = (uint32_t *)select_user_reg(regs, cp32.reg);

    if ( cp32.read )
        perfc_incr(vtimer_cp32_reads);
    else
        perfc_incr(vtimer_cp32_writes);

    switch ( hsr.bits & HSR_CP32_REGS_MASK )
    {
    case HSR_CPREG32(CNTP_CTL):
        return vtimer_cntp_ctl(regs, r, cp32.read);

    case HSR_CPREG32(CNTP_TVAL):
        return vtimer_cntp_tval(regs, r, cp32.read);

    default:
        return 0;
    }
}
Exemplo n.º 14
0
Arquivo: vtimer.c Projeto: Xilinx/xen
static bool vtimer_emulate_sysreg(struct cpu_user_regs *regs, union hsr hsr)
{
    struct hsr_sysreg sysreg = hsr.sysreg;

    if ( sysreg.read )
        perfc_incr(vtimer_sysreg_reads);
    else
        perfc_incr(vtimer_sysreg_writes);

    switch ( hsr.bits & HSR_SYSREG_REGS_MASK )
    {
    case HSR_SYSREG_CNTP_CTL_EL0:
        return vreg_emulate_sysreg32(regs, hsr, vtimer_cntp_ctl);
    case HSR_SYSREG_CNTP_TVAL_EL0:
        return vreg_emulate_sysreg32(regs, hsr, vtimer_cntp_tval);
    case HSR_SYSREG_CNTP_CVAL_EL0:
        return vreg_emulate_sysreg64(regs, hsr, vtimer_cntp_cval);

    default:
        return false;
    }

}
Exemplo n.º 15
0
static int vuart_mmio_write(struct vcpu *v, mmio_info_t *info, void *priv)
{
    struct domain *d = v->domain;
    struct hsr_dabt dabt = info->dabt;
    struct cpu_user_regs *regs = guest_cpu_user_regs();
    register_t *r = select_user_reg(regs, dabt.reg);
    paddr_t offset = info->gpa - d->arch.vuart.info->base_addr;

    perfc_incr(vuart_writes);

    if ( offset == d->arch.vuart.info->data_off )
        /* ignore any status bits */
        vuart_print_char(v, *r & 0xFF);

    return 1;
}
Exemplo n.º 16
0
static int vuart_mmio_read(struct vcpu *v, mmio_info_t *info, void *priv)
{
    struct domain *d = v->domain;
    struct hsr_dabt dabt = info->dabt;
    struct cpu_user_regs *regs = guest_cpu_user_regs();
    register_t *r = select_user_reg(regs, dabt.reg);
    paddr_t offset = info->gpa - d->arch.vuart.info->base_addr;

    perfc_incr(vuart_reads);

    /* By default zeroed the register */
    *r = 0;

    if ( offset == d->arch.vuart.info->status_off )
        /* All holding registers empty, ready to send etc */
        *r = d->arch.vuart.info->status;

    return 1;
}
Exemplo n.º 17
0
static void vtimer_interrupt(int irq, void *dev_id, struct cpu_user_regs *regs)
{
    /*
     * Edge-triggered interrupts can be used for the virtual timer. Even
     * if the timer output signal is masked in the context switch, the
     * GIC will keep track that of any interrupts raised while IRQS are
     * disabled. As soon as IRQs are re-enabled, the virtual interrupt
     * will be injected to Xen.
     *
     * If an IDLE vCPU was scheduled next then we should ignore the
     * interrupt.
     */
    if ( unlikely(is_idle_vcpu(current)) )
        return;

    perfc_incr(virt_timer_irqs);

    current->arch.virt_timer.ctl = READ_SYSREG32(CNTV_CTL_EL0);
    WRITE_SYSREG32(current->arch.virt_timer.ctl | CNTx_CTL_MASK, CNTV_CTL_EL0);
    vgic_vcpu_inject_irq(current, current->arch.virt_timer.irq);
}
Exemplo n.º 18
0
int get_page_type(struct page_info *page, unsigned long type)
{
    unsigned long nx, x, y = page->u.inuse.type_info;

    ASSERT(!(type & ~PGT_type_mask));

 again:
    do {
        x  = y;
        nx = x + 1;
        if ( unlikely((nx & PGT_count_mask) == 0) )
        {
            MEM_LOG("Type count overflow on pfn %lx", page_to_mfn(page));
            return 0;
        }
        else if ( unlikely((x & PGT_count_mask) == 0) )
        {
            if ( (x & PGT_type_mask) != type )
            {
                /*
                 * On type change we check to flush stale TLB entries. This 
                 * may be unnecessary (e.g., page was GDT/LDT) but those 
                 * circumstances should be very rare.
                 */
                cpumask_t mask =
                    page_get_owner(page)->domain_dirty_cpumask;
                tlbflush_filter(mask, page->tlbflush_timestamp);

                if ( unlikely(!cpus_empty(mask)) )
                {
                    perfc_incr(need_flush_tlb_flush);
                    flush_tlb_mask(mask);
                }

                /* We lose existing type, back pointer, and validity. */
                nx &= ~(PGT_type_mask | PGT_validated);
                nx |= type;

                /* No special validation needed for writable pages. */
                /* Page tables and GDT/LDT need to be scanned for validity. */
                if ( type == PGT_writable_page )
                    nx |= PGT_validated;
            }
        }
        else if ( unlikely((x & PGT_type_mask) != type) )
        {
            return 0;
        }
        else if ( unlikely(!(x & PGT_validated)) )
        {
            /* Someone else is updating validation of this page. Wait... */
            while ( (y = page->u.inuse.type_info) == x )
                cpu_relax();
            goto again;
        }
    }
    while ( unlikely((y = cmpxchg(&page->u.inuse.type_info, x, nx)) != x) );

    if ( unlikely(!(nx & PGT_validated)) )
    {
        /* Noone else is updating simultaneously. */
        __set_bit(_PGT_validated, &page->u.inuse.type_info);
    }

    return 1;
}
Exemplo n.º 19
0
Arquivo: irq.c Projeto: doniexun/xen
/* Dispatch an interrupt */
void do_IRQ(struct cpu_user_regs *regs, unsigned int irq, int is_fiq)
{
    struct irq_desc *desc = irq_to_desc(irq);

    perfc_incr(irqs);

    ASSERT(irq >= 16); /* SGIs do not come down this path */

    if (irq < 32)
        perfc_incr(ppis);
    else
        perfc_incr(spis);

    /* TODO: this_cpu(irq_count)++; */

    irq_enter();

    spin_lock(&desc->lock);
    desc->handler->ack(desc);

    if ( !desc->action )
    {
        printk("Unknown %s %#3.3x\n",
               is_fiq ? "FIQ" : "IRQ", irq);
        goto out;
    }

    if ( test_bit(_IRQ_GUEST, &desc->status) )
    {
        struct irq_guest *info = irq_get_guest_info(desc);

        perfc_incr(guest_irqs);
        desc->handler->end(desc);

        set_bit(_IRQ_INPROGRESS, &desc->status);

        /*
         * The irq cannot be a PPI, we only support delivery of SPIs to
         * guests.
	 */
        vgic_vcpu_inject_spi(info->d, info->virq);
        goto out_no_end;
    }

    set_bit(_IRQ_PENDING, &desc->status);

    /*
     * Since we set PENDING, if another processor is handling a different
     * instance of this same irq, the other processor will take care of it.
     */
    if ( test_bit(_IRQ_DISABLED, &desc->status) ||
         test_bit(_IRQ_INPROGRESS, &desc->status) )
        goto out;

    set_bit(_IRQ_INPROGRESS, &desc->status);

    while ( test_bit(_IRQ_PENDING, &desc->status) )
    {
        struct irqaction *action;

        clear_bit(_IRQ_PENDING, &desc->status);
        action = desc->action;

        spin_unlock_irq(&desc->lock);

        do
        {
            action->handler(irq, action->dev_id, regs);
            action = action->next;
        } while ( action );

        spin_lock_irq(&desc->lock);
    }

    clear_bit(_IRQ_INPROGRESS, &desc->status);

out:
    desc->handler->end(desc);
out_no_end:
    spin_unlock(&desc->lock);
    irq_exit();
}
Exemplo n.º 20
0
void call_function_interrupt(struct cpu_user_regs *regs)
{
    ack_APIC_irq();
    perfc_incr(ipis);
    smp_call_function_interrupt();
}
Exemplo n.º 21
0
IA64FAULT
ia64_hypercall(struct pt_regs *regs)
{
	struct vcpu *v = current;
	struct sal_ret_values x;
	efi_status_t efi_ret_value;
	fpswa_ret_t fpswa_ret;
	IA64FAULT fault; 
	unsigned long index = regs->r2 & FW_HYPERCALL_NUM_MASK_HIGH;

	perfc_incra(fw_hypercall, index >> 8);
	switch (index) {
	case FW_HYPERCALL_XEN:
		return xen_hypercall(regs);

	case FW_HYPERCALL_XEN_FAST:
		return xen_fast_hypercall(regs);

	case FW_HYPERCALL_PAL_CALL:
		//printk("*** PAL hypercall: index=%d\n",regs->r28);
		//FIXME: This should call a C routine
#if 0
		// This is very conservative, but avoids a possible
		// (and deadly) freeze in paravirtualized domains due
		// to a yet-to-be-found bug where pending_interruption
		// is zero when it shouldn't be. Since PAL is called
		// in the idle loop, this should resolve it
		VCPU(v,pending_interruption) = 1;
#endif
		if (regs->r28 == PAL_HALT_LIGHT) {
			if (vcpu_deliverable_interrupts(v) ||
				event_pending(v)) {
				perfc_incr(idle_when_pending);
				vcpu_pend_unspecified_interrupt(v);
//printk("idle w/int#%d pending!\n",pi);
//this shouldn't happen, but it apparently does quite a bit!  so don't
//allow it to happen... i.e. if a domain has an interrupt pending and
//it tries to halt itself because it thinks it is idle, just return here
//as deliver_pending_interrupt is called on the way out and will deliver it
			}
			else {
				perfc_incr(pal_halt_light);
				migrate_timer(&v->arch.hlt_timer,
				              v->processor);
				set_timer(&v->arch.hlt_timer,
				          vcpu_get_next_timer_ns(v));
				do_sched_op_compat(SCHEDOP_block, 0);
				/* do_block only pends a softirq */
				do_softirq();
				stop_timer(&v->arch.hlt_timer);
				/* do_block() calls
				 * local_event_delivery_enable(),
				 * but PAL CALL must be called with
				 * psr.i = 0 and psr.i is unchanged.
				 * SDM vol.2 Part I 11.10.2
				 * PAL Calling Conventions.
				 */
				local_event_delivery_disable();
			}
			regs->r8 = 0;
			regs->r9 = 0;
			regs->r10 = 0;
			regs->r11 = 0;
		}
		else {
			struct ia64_pal_retval y;

			if (regs->r28 >= PAL_COPY_PAL)
				y = xen_pal_emulator
					(regs->r28, vcpu_get_gr (v, 33),
					 vcpu_get_gr (v, 34),
					 vcpu_get_gr (v, 35));
			else
				y = xen_pal_emulator(regs->r28,regs->r29,
						     regs->r30,regs->r31);
			regs->r8 = y.status; regs->r9 = y.v0;
			regs->r10 = y.v1; regs->r11 = y.v2;
		}
		break;
	case FW_HYPERCALL_SAL_CALL:
		x = sal_emulator(vcpu_get_gr(v,32),vcpu_get_gr(v,33),
			vcpu_get_gr(v,34),vcpu_get_gr(v,35),
			vcpu_get_gr(v,36),vcpu_get_gr(v,37),
			vcpu_get_gr(v,38),vcpu_get_gr(v,39));
		regs->r8 = x.r8; regs->r9 = x.r9;
		regs->r10 = x.r10; regs->r11 = x.r11;
		break;
	case FW_HYPERCALL_SAL_RETURN:
	        if ( !test_and_set_bit(_VPF_down, &v->pause_flags) )
			vcpu_sleep_nosync(v);
		break;
	case FW_HYPERCALL_EFI_CALL:
		efi_ret_value = efi_emulator (regs, &fault);
		if (fault != IA64_NO_FAULT) return fault;
		regs->r8 = efi_ret_value;
		break;
	case FW_HYPERCALL_IPI:
		fw_hypercall_ipi (regs);
		break;
	case FW_HYPERCALL_SET_SHARED_INFO_VA:
	        regs->r8 = domain_set_shared_info_va (regs->r28);
		break;
	case FW_HYPERCALL_FPSWA_BASE:
		switch (regs->r2) {
		case FW_HYPERCALL_FPSWA_BROKEN:
			gdprintk(XENLOG_WARNING,
				 "Old fpswa hypercall was called (0x%lx).\n"
				 "Please update your domain builder. ip 0x%lx\n",
				 FW_HYPERCALL_FPSWA_BROKEN, regs->cr_iip);
			fpswa_ret = fw_hypercall_fpswa_error();
			break;
		case FW_HYPERCALL_FPSWA:
			fpswa_ret = fw_hypercall_fpswa(v, regs);
			break;
		default:
			gdprintk(XENLOG_ERR, "unknown fpswa hypercall %lx\n",
				 regs->r2);
			fpswa_ret = fw_hypercall_fpswa_error();
			break;
		}
		regs->r8  = fpswa_ret.status;
		regs->r9  = fpswa_ret.err0;
		regs->r10 = fpswa_ret.err1;
		regs->r11 = fpswa_ret.err2;
		break;
	case __HYPERVISOR_opt_feature:
	{
		XEN_GUEST_HANDLE(void) arg;
		struct xen_ia64_opt_feature optf;
		set_xen_guest_handle(arg, (void*)(vcpu_get_gr(v, 32)));
		if (copy_from_guest(&optf, arg, 1) == 0)
			regs->r8 = domain_opt_feature(v->domain, &optf);
		else
			regs->r8 = -EFAULT;
		break;
	}
	case FW_HYPERCALL_SIOEMU:
		sioemu_hypercall(regs);
		break;
	default:
		printk("unknown ia64 fw hypercall %lx\n", regs->r2);
		regs->r8 = do_ni_hypercall();
	}
	return IA64_NO_FAULT;
}
Exemplo n.º 22
0
static void realmode_emulate_one(struct hvm_emulate_ctxt *hvmemul_ctxt)
{
    struct vcpu *curr = current;
    uint32_t intr_info;
    int rc;

    perfc_incr(realmode_emulations);

    rc = hvm_emulate_one(hvmemul_ctxt);

    if ( rc == X86EMUL_UNHANDLEABLE )
    {
        gdprintk(XENLOG_ERR, "Failed to emulate insn.\n");
        goto fail;
    }

    if ( rc == X86EMUL_EXCEPTION )
    {
        if ( !hvmemul_ctxt->exn_pending )
        {
            intr_info = __vmread(VM_ENTRY_INTR_INFO);
            __vmwrite(VM_ENTRY_INTR_INFO, 0);
            if ( !(intr_info & INTR_INFO_VALID_MASK) )
            {
                gdprintk(XENLOG_ERR, "Exception pending but no info.\n");
                goto fail;
            }
            hvmemul_ctxt->exn_vector = (uint8_t)intr_info;
            hvmemul_ctxt->exn_insn_len = 0;
        }

        if ( unlikely(curr->domain->debugger_attached) &&
             ((hvmemul_ctxt->exn_vector == TRAP_debug) ||
              (hvmemul_ctxt->exn_vector == TRAP_int3)) )
        {
            domain_pause_for_debugger();
        }
        else if ( curr->arch.hvm_vcpu.guest_cr[0] & X86_CR0_PE )
        {
            gdprintk(XENLOG_ERR, "Exception %02x in protected mode.\n",
                     hvmemul_ctxt->exn_vector);
            goto fail;
        }
        else
        {
            realmode_deliver_exception(
                hvmemul_ctxt->exn_vector,
                hvmemul_ctxt->exn_insn_len,
                hvmemul_ctxt);
        }
    }

    return;

 fail:
    gdprintk(XENLOG_ERR,
             "Real-mode emulation failed @ %04x:%08lx: "
             "%02x %02x %02x %02x %02x %02x\n",
             hvmemul_get_seg_reg(x86_seg_cs, hvmemul_ctxt)->sel,
             hvmemul_ctxt->insn_buf_eip,
             hvmemul_ctxt->insn_buf[0], hvmemul_ctxt->insn_buf[1],
             hvmemul_ctxt->insn_buf[2], hvmemul_ctxt->insn_buf[3],
             hvmemul_ctxt->insn_buf[4], hvmemul_ctxt->insn_buf[5]);
    domain_crash(curr->domain);
}
Exemplo n.º 23
0
void pv_hypercall(struct cpu_user_regs *regs)
{
    struct vcpu *curr = current;
    unsigned long eax;

    ASSERT(guest_kernel_mode(curr, regs));

    eax = is_pv_32bit_vcpu(curr) ? regs->eax : regs->rax;

    BUILD_BUG_ON(ARRAY_SIZE(pv_hypercall_table) >
                 ARRAY_SIZE(hypercall_args_table));

    if ( (eax >= ARRAY_SIZE(pv_hypercall_table)) ||
         !pv_hypercall_table[eax].native )
    {
        regs->rax = -ENOSYS;
        return;
    }

    curr->hcall_preempted = false;

    if ( !is_pv_32bit_vcpu(curr) )
    {
        unsigned long rdi = regs->rdi;
        unsigned long rsi = regs->rsi;
        unsigned long rdx = regs->rdx;
        unsigned long r10 = regs->r10;
        unsigned long r8 = regs->r8;
        unsigned long r9 = regs->r9;

#ifndef NDEBUG
        /* Deliberately corrupt parameter regs not used by this hypercall. */
        switch ( hypercall_args_table[eax].native )
        {
        case 0: rdi = 0xdeadbeefdeadf00dUL;
        case 1: rsi = 0xdeadbeefdeadf00dUL;
        case 2: rdx = 0xdeadbeefdeadf00dUL;
        case 3: r10 = 0xdeadbeefdeadf00dUL;
        case 4: r8 = 0xdeadbeefdeadf00dUL;
        case 5: r9 = 0xdeadbeefdeadf00dUL;
        }
#endif
        if ( unlikely(tb_init_done) )
        {
            unsigned long args[6] = { rdi, rsi, rdx, r10, r8, r9 };

            __trace_hypercall(TRC_PV_HYPERCALL_V2, eax, args);
        }

        regs->rax = pv_hypercall_table[eax].native(rdi, rsi, rdx, r10, r8, r9);

#ifndef NDEBUG
        if ( !curr->hcall_preempted )
        {
            /* Deliberately corrupt parameter regs used by this hypercall. */
            switch ( hypercall_args_table[eax].native )
            {
            case 6: regs->r9  = 0xdeadbeefdeadf00dUL;
            case 5: regs->r8  = 0xdeadbeefdeadf00dUL;
            case 4: regs->r10 = 0xdeadbeefdeadf00dUL;
            case 3: regs->rdx = 0xdeadbeefdeadf00dUL;
            case 2: regs->rsi = 0xdeadbeefdeadf00dUL;
            case 1: regs->rdi = 0xdeadbeefdeadf00dUL;
            }
        }
#endif
    }
    else
    {
        unsigned int ebx = regs->ebx;
        unsigned int ecx = regs->ecx;
        unsigned int edx = regs->edx;
        unsigned int esi = regs->esi;
        unsigned int edi = regs->edi;
        unsigned int ebp = regs->ebp;

#ifndef NDEBUG
        /* Deliberately corrupt parameter regs not used by this hypercall. */
        switch ( hypercall_args_table[eax].compat )
        {
        case 0: ebx = 0xdeadf00d;
        case 1: ecx = 0xdeadf00d;
        case 2: edx = 0xdeadf00d;
        case 3: esi = 0xdeadf00d;
        case 4: edi = 0xdeadf00d;
        case 5: ebp = 0xdeadf00d;
        }
#endif

        if ( unlikely(tb_init_done) )
        {
            unsigned long args[6] = { ebx, ecx, edx, esi, edi, ebp };

            __trace_hypercall(TRC_PV_HYPERCALL_V2, eax, args);
        }

        curr->hcall_compat = true;
        regs->eax = pv_hypercall_table[eax].compat(ebx, ecx, edx, esi, edi, ebp);
        curr->hcall_compat = false;

#ifndef NDEBUG
        if ( !curr->hcall_preempted )
        {
            /* Deliberately corrupt parameter regs used by this hypercall. */
            switch ( hypercall_args_table[eax].compat )
            {
            case 6: regs->ebp = 0xdeadf00d;
            case 5: regs->edi = 0xdeadf00d;
            case 4: regs->esi = 0xdeadf00d;
            case 3: regs->edx = 0xdeadf00d;
            case 2: regs->ecx = 0xdeadf00d;
            case 1: regs->ebx = 0xdeadf00d;
            }
        }
#endif
    }

    /*
     * PV guests use SYSCALL or INT $0x82 to make a hypercall, both of which
     * have trap semantics.  If the hypercall has been preempted, rewind the
     * instruction pointer to reexecute the instruction.
     */
    if ( curr->hcall_preempted )
        regs->rip -= 2;

    perfc_incr(hypercalls);
}
Exemplo n.º 24
0
Arquivo: viridian.c Projeto: djs55/xen
int viridian_hypercall(struct cpu_user_regs *regs)
{
    struct vcpu *curr = current;
    struct domain *currd = curr->domain;
    int mode = hvm_guest_x86_mode(curr);
    unsigned long input_params_gpa, output_params_gpa;
    uint16_t status = HV_STATUS_SUCCESS;

    union hypercall_input {
        uint64_t raw;
        struct {
            uint16_t call_code;
            uint16_t fast:1;
            uint16_t rsvd1:15;
            uint16_t rep_count:12;
            uint16_t rsvd2:4;
            uint16_t rep_start:12;
            uint16_t rsvd3:4;
        };
    } input;

    union hypercall_output {
        uint64_t raw;
        struct {
            uint16_t result;
            uint16_t rsvd1;
            uint32_t rep_complete:12;
            uint32_t rsvd2:20;
        };
    } output = { 0 };

    ASSERT(is_viridian_domain(currd));

    switch ( mode )
    {
    case 8:
        input.raw = regs->rcx;
        input_params_gpa = regs->rdx;
        output_params_gpa = regs->r8;
        break;
    case 4:
        input.raw = (regs->rdx << 32) | regs->_eax;
        input_params_gpa = (regs->rbx << 32) | regs->_ecx;
        output_params_gpa = (regs->rdi << 32) | regs->_esi;
        break;
    default:
        goto out;
    }

    switch ( input.call_code )
    {
    case HvNotifyLongSpinWait:
        /*
         * See Microsoft Hypervisor Top Level Spec. section 18.5.1.
         */
        perfc_incr(mshv_call_long_wait);
        do_sched_op(SCHEDOP_yield, guest_handle_from_ptr(NULL, void));
        status = HV_STATUS_SUCCESS;
        break;

    case HvFlushVirtualAddressSpace:
    case HvFlushVirtualAddressList:
    {
        cpumask_t *pcpu_mask;
        struct vcpu *v;
        struct {
            uint64_t address_space;
            uint64_t flags;
            uint64_t vcpu_mask;
        } input_params;

        /*
         * See Microsoft Hypervisor Top Level Spec. sections 12.4.2
         * and 12.4.3.
         */
        perfc_incr(mshv_call_flush);

        /* These hypercalls should never use the fast-call convention. */
        status = HV_STATUS_INVALID_PARAMETER;
        if ( input.fast )
            break;

        /* Get input parameters. */
        if ( hvm_copy_from_guest_phys(&input_params, input_params_gpa,
                                      sizeof(input_params)) != HVMCOPY_okay )
            break;

        /*
         * It is not clear from the spec. if we are supposed to
         * include current virtual CPU in the set or not in this case,
         * so err on the safe side.
         */
        if ( input_params.flags & HV_FLUSH_ALL_PROCESSORS )
            input_params.vcpu_mask = ~0ul;

        pcpu_mask = &this_cpu(ipi_cpumask);
        cpumask_clear(pcpu_mask);

        /*
         * For each specified virtual CPU flush all ASIDs to invalidate
         * TLB entries the next time it is scheduled and then, if it
         * is currently running, add its physical CPU to a mask of
         * those which need to be interrupted to force a flush.
         */
        for_each_vcpu ( currd, v )
        {
            if ( v->vcpu_id >= (sizeof(input_params.vcpu_mask) * 8) )
                break;

            if ( !(input_params.vcpu_mask & (1ul << v->vcpu_id)) )
                continue;

            hvm_asid_flush_vcpu(v);
            if ( v != curr && v->is_running )
                __cpumask_set_cpu(v->processor, pcpu_mask);
        }

        /*
         * Since ASIDs have now been flushed it just remains to
         * force any CPUs currently running target vCPUs out of non-
         * root mode. It's possible that re-scheduling has taken place
         * so we may unnecessarily IPI some CPUs.
         */
        if ( !cpumask_empty(pcpu_mask) )
            smp_send_event_check_mask(pcpu_mask);

        output.rep_complete = input.rep_count;

        status = HV_STATUS_SUCCESS;
        break;
    }

    default:
        status = HV_STATUS_INVALID_HYPERCALL_CODE;
        break;
    }

out:
    output.result = status;
    switch (mode) {
    case 8:
        regs->rax = output.raw;
        break;
    default:
        regs->rdx = output.raw >> 32;
        regs->rax = (uint32_t)output.raw;
        break;
    }

    return HVM_HCALL_completed;
}
Exemplo n.º 25
0
Arquivo: viridian.c Projeto: djs55/xen
int rdmsr_viridian_regs(uint32_t idx, uint64_t *val)
{
    struct vcpu *v = current;
    struct domain *d = v->domain;
    
    if ( !is_viridian_domain(d) )
        return 0;

    switch ( idx )
    {
    case VIRIDIAN_MSR_GUEST_OS_ID:
        perfc_incr(mshv_rdmsr_osid);
        *val = d->arch.hvm_domain.viridian.guest_os_id.raw;
        break;

    case VIRIDIAN_MSR_HYPERCALL:
        perfc_incr(mshv_rdmsr_hc_page);
        *val = d->arch.hvm_domain.viridian.hypercall_gpa.raw;
        break;

    case VIRIDIAN_MSR_VP_INDEX:
        perfc_incr(mshv_rdmsr_vp_index);
        *val = v->vcpu_id;
        break;

    case VIRIDIAN_MSR_TSC_FREQUENCY:
        if ( viridian_feature_mask(d) & HVMPV_no_freq )
            return 0;

        perfc_incr(mshv_rdmsr_tsc_frequency);
        *val = (uint64_t)d->arch.tsc_khz * 1000ull;
        break;

    case VIRIDIAN_MSR_APIC_FREQUENCY:
        if ( viridian_feature_mask(d) & HVMPV_no_freq )
            return 0;

        perfc_incr(mshv_rdmsr_apic_frequency);
        *val = 1000000000ull / APIC_BUS_CYCLE_NS;
        break;

    case VIRIDIAN_MSR_ICR:
        perfc_incr(mshv_rdmsr_icr);
        *val = (((uint64_t)vlapic_get_reg(vcpu_vlapic(v), APIC_ICR2) << 32) |
                vlapic_get_reg(vcpu_vlapic(v), APIC_ICR));
        break;

    case VIRIDIAN_MSR_TPR:
        perfc_incr(mshv_rdmsr_tpr);
        *val = vlapic_get_reg(vcpu_vlapic(v), APIC_TASKPRI);
        break;

    case VIRIDIAN_MSR_APIC_ASSIST:
        perfc_incr(mshv_rdmsr_apic_msr);
        *val = v->arch.hvm_vcpu.viridian.apic_assist.msr.raw;
        break;

    case VIRIDIAN_MSR_REFERENCE_TSC:
        if ( !(viridian_feature_mask(d) & HVMPV_reference_tsc) )
            return 0;

        perfc_incr(mshv_rdmsr_tsc_msr);
        *val = d->arch.hvm_domain.viridian.reference_tsc.raw;
        break;

    case VIRIDIAN_MSR_TIME_REF_COUNT:
    {
        struct viridian_time_ref_count *trc;

        trc = &d->arch.hvm_domain.viridian.time_ref_count;

        if ( !(viridian_feature_mask(d) & HVMPV_time_ref_count) )
            return 0;

        if ( !test_and_set_bit(_TRC_accessed, &trc->flags) )
            printk(XENLOG_G_INFO "d%d: VIRIDIAN MSR_TIME_REF_COUNT: accessed\n",
                   d->domain_id);

        perfc_incr(mshv_rdmsr_time_ref_count);
        *val = raw_trc_val(d) + trc->off;
        break;
    }

    default:
        return 0;
    }

    return 1;
}
Exemplo n.º 26
0
Arquivo: viridian.c Projeto: djs55/xen
int wrmsr_viridian_regs(uint32_t idx, uint64_t val)
{
    struct vcpu *v = current;
    struct domain *d = v->domain;

    if ( !is_viridian_domain(d) )
        return 0;

    switch ( idx )
    {
    case VIRIDIAN_MSR_GUEST_OS_ID:
        perfc_incr(mshv_wrmsr_osid);
        d->arch.hvm_domain.viridian.guest_os_id.raw = val;
        dump_guest_os_id(d);
        break;

    case VIRIDIAN_MSR_HYPERCALL:
        perfc_incr(mshv_wrmsr_hc_page);
        d->arch.hvm_domain.viridian.hypercall_gpa.raw = val;
        dump_hypercall(d);
        if ( d->arch.hvm_domain.viridian.hypercall_gpa.fields.enabled )
            enable_hypercall_page(d);
        break;

    case VIRIDIAN_MSR_VP_INDEX:
        perfc_incr(mshv_wrmsr_vp_index);
        break;

    case VIRIDIAN_MSR_EOI:
        perfc_incr(mshv_wrmsr_eoi);
        vlapic_EOI_set(vcpu_vlapic(v));
        break;

    case VIRIDIAN_MSR_ICR: {
        u32 eax = (u32)val, edx = (u32)(val >> 32);
        struct vlapic *vlapic = vcpu_vlapic(v);
        perfc_incr(mshv_wrmsr_icr);
        eax &= ~(1 << 12);
        edx &= 0xff000000;
        vlapic_set_reg(vlapic, APIC_ICR2, edx);
        vlapic_ipi(vlapic, eax, edx);
        vlapic_set_reg(vlapic, APIC_ICR, eax);
        break;
    }

    case VIRIDIAN_MSR_TPR:
        perfc_incr(mshv_wrmsr_tpr);
        vlapic_set_reg(vcpu_vlapic(v), APIC_TASKPRI, (uint8_t)val);
        break;

    case VIRIDIAN_MSR_APIC_ASSIST:
        perfc_incr(mshv_wrmsr_apic_msr);
        teardown_apic_assist(v); /* release any previous mapping */
        v->arch.hvm_vcpu.viridian.apic_assist.msr.raw = val;
        dump_apic_assist(v);
        if ( v->arch.hvm_vcpu.viridian.apic_assist.msr.fields.enabled )
            initialize_apic_assist(v);
        break;

    case VIRIDIAN_MSR_REFERENCE_TSC:
        if ( !(viridian_feature_mask(d) & HVMPV_reference_tsc) )
            return 0;

        perfc_incr(mshv_wrmsr_tsc_msr);
        d->arch.hvm_domain.viridian.reference_tsc.raw = val;
        dump_reference_tsc(d);
        if ( d->arch.hvm_domain.viridian.reference_tsc.fields.enabled )
            update_reference_tsc(d, 1);
        break;

    default:
        return 0;
    }

    return 1;
}
Exemplo n.º 27
0
void event_check_interrupt(struct cpu_user_regs *regs)
{
    ack_APIC_irq();
    perfc_incr(ipis);
    this_cpu(irq_count)++;
}
Exemplo n.º 28
0
int viridian_hypercall(struct cpu_user_regs *regs)
{
    int mode = hvm_guest_x86_mode(current);
    unsigned long __attribute__((__unused__)) input_params_gpa, output_params_gpa;
    uint16_t status = HV_STATUS_SUCCESS;

    union hypercall_input {
        uint64_t raw;
        struct {
            uint16_t call_code;
            uint16_t rsvd1;
            unsigned rep_count:12;
            unsigned rsvd2:4;
            unsigned rep_start:12;
            unsigned rsvd3:4;
        };
    } input;

    union hypercall_output {
        uint64_t raw;
        struct {
            uint16_t result;
            uint16_t rsvd1;
            unsigned rep_complete:12;
            unsigned rsvd2:20;
        };
    } output = { 0 };

    ASSERT(is_viridian_domain(current->domain));

    switch ( mode )
    {
#ifdef __x86_64__
    case 8:
        input.raw = regs->rcx;
        input_params_gpa = regs->rdx;
        output_params_gpa = regs->r8;
        break;
#endif
    case 4:
        input.raw = ((uint64_t)regs->edx << 32) | regs->eax;
        input_params_gpa = ((uint64_t)regs->ebx << 32) | regs->ecx;
        output_params_gpa = ((uint64_t)regs->edi << 32) | regs->esi;
        break;
    default:
        goto out;
    }

    switch ( input.call_code )
    {
    case HvNotifyLongSpinWait:
        perfc_incr(mshv_call_long_wait);
        do_sched_op_compat(SCHEDOP_yield, 0);
        status = HV_STATUS_SUCCESS;
        break;
    default:
        status = HV_STATUS_INVALID_HYPERCALL_CODE;
        break;
    }

out:
    output.result = status;
    switch (mode) {
#ifdef __x86_64__
    case 8:
        regs->rax = output.raw;
        break;
#endif
    default:
        regs->edx = output.raw >> 32;
        regs->eax = output.raw;
        break;
    }

    return HVM_HCALL_completed;
}
Exemplo n.º 29
0
void apic_timer_interrupt(struct cpu_user_regs * regs)
{
    ack_APIC_irq();
    perfc_incr(apic_timer);
    raise_softirq(TIMER_SOFTIRQ);
}
Exemplo n.º 30
0
int wrmsr_viridian_regs(uint32_t idx, uint64_t val)
{
    struct domain *d = current->domain;

    if ( !is_viridian_domain(d) )
        return 0;

    switch ( idx )
    {
    case VIRIDIAN_MSR_GUEST_OS_ID:
        perfc_incr(mshv_wrmsr_osid);
        d->arch.hvm_domain.viridian.guest_os_id.raw = val;
        gdprintk(XENLOG_INFO, "Guest os:\n");
        gdprintk(XENLOG_INFO, "\tvendor: %x\n",
               d->arch.hvm_domain.viridian.guest_os_id.fields.vendor);
        gdprintk(XENLOG_INFO, "\tos: %x\n",
               d->arch.hvm_domain.viridian.guest_os_id.fields.os);
        gdprintk(XENLOG_INFO, "\tmajor: %x\n",
               d->arch.hvm_domain.viridian.guest_os_id.fields.major);
        gdprintk(XENLOG_INFO, "\tminor: %x\n",
               d->arch.hvm_domain.viridian.guest_os_id.fields.minor);
        gdprintk(XENLOG_INFO, "\tsp: %x\n",
               d->arch.hvm_domain.viridian.guest_os_id.fields.service_pack);
        gdprintk(XENLOG_INFO, "\tbuild: %x\n",
               d->arch.hvm_domain.viridian.guest_os_id.fields.build_number);
        break;

    case VIRIDIAN_MSR_HYPERCALL:
        perfc_incr(mshv_wrmsr_hc_page);
        gdprintk(XENLOG_INFO, "Set hypercall page %"PRIx64".\n", val);
        if ( d->arch.hvm_domain.viridian.guest_os_id.raw == 0 )
            break;
        d->arch.hvm_domain.viridian.hypercall_gpa.raw = val;
        if ( d->arch.hvm_domain.viridian.hypercall_gpa.fields.enabled )
            enable_hypercall_page();
        break;

    case VIRIDIAN_MSR_VP_INDEX:
        perfc_incr(mshv_wrmsr_vp_index);
        gdprintk(XENLOG_INFO, "Set VP index %"PRIu64".\n", val);
        break;

    case VIRIDIAN_MSR_EOI:
        perfc_incr(mshv_wrmsr_eoi);
        vlapic_EOI_set(vcpu_vlapic(current));
        break;

    case VIRIDIAN_MSR_ICR: {
        u32 eax = (u32)val, edx = (u32)(val >> 32);
        struct vlapic *vlapic = vcpu_vlapic(current);
        perfc_incr(mshv_wrmsr_icr);
        eax &= ~(1 << 12);
        edx &= 0xff000000;
        vlapic_set_reg(vlapic, APIC_ICR2, edx);
        if ( vlapic_ipi(vlapic, eax, edx) == X86EMUL_OKAY )
            vlapic_set_reg(vlapic, APIC_ICR, eax);
        break;
    }

    case VIRIDIAN_MSR_TPR:
        perfc_incr(mshv_wrmsr_tpr);
        vlapic_set_reg(vcpu_vlapic(current), APIC_TASKPRI, (uint8_t)val);
        break;

    case VIRIDIAN_MSR_APIC_ASSIST:
        /*
         * We don't support the APIC assist page, and that fact is reflected in
         * our CPUID flags. However, Windows 7 build 7000 has a bug which means
         * that it doesn't recognise that, and tries to use the page anyway. We
         * therefore have to fake up just enough to keep win7 happy.
         * Fortunately, that's really easy: just setting the first four bytes
         * in the page to zero effectively disables the page again, so that's
         * what we do. Semantically, the first four bytes are supposed to be a
         * flag saying whether the guest really needs to issue an EOI. Setting
         * that flag to zero means that it must always issue one, which is what
         * we want. Once a page has been repurposed as an APIC assist page the
         * guest isn't allowed to set anything in it, so the flag remains zero
         * and all is fine. The guest is allowed to clear flags in the page,
         * but that doesn't cause us any problems.
         */
        if ( val & 1 ) /* APIC assist page enabled? */
        {
            uint32_t word = 0;
            paddr_t page_start = val & ~1ul;
            (void)hvm_copy_to_guest_phys(page_start, &word, sizeof(word));
        }
        break;

    default:
        return 0;
    }

    return 1;
}