C++ xen_pv_domain函数代码示例

static int gnttab_setup(void)
{
	int rc;
	unsigned int max_nr_gframes;

	max_nr_gframes = gnttab_max_grant_frames();
	if (max_nr_gframes < nr_grant_frames)
		return -ENOSYS;

	if (xen_pv_domain() && xen_feature(XENFEAT_auto_translated_physmap) &&
	    !gnttab_shared.addr) {

		rc = xlated_setup_gnttab_pages((unsigned long)max_nr_gframes,
					       &gnttab_shared.addr);
		if (rc != 0)
			return rc;
	}
	if (xen_pv_domain())
		return gnttab_map(0, nr_grant_frames - 1);

	if (gnttab_shared.addr == NULL) {
		gnttab_shared.addr = xen_remap(xen_hvm_resume_frames,
						PAGE_SIZE * max_nr_gframes);
		if (gnttab_shared.addr == NULL) {
			printk(KERN_WARNING
					"Failed to ioremap gnttab share frames!");
			return -ENOMEM;
		}
	}

	gnttab_map(0, nr_grant_frames - 1);

	return 0;
}

static void
xen_hvm_disable_emulated_devices(void)
{
	u_short disable_devs = 0;

	if (xen_pv_domain()) {
		/*
		 * No emulated devices in the PV case, so no need to unplug
		 * anything.
		 */
		if (xen_disable_pv_disks != 0 || xen_disable_pv_nics != 0)
			printf("PV devices cannot be disabled in PV guests\n");
		return;
	}

	if (inw(XEN_MAGIC_IOPORT) != XMI_MAGIC)
		return;

	if (xen_disable_pv_disks == 0) {
		if (bootverbose)
			printf("XEN: disabling emulated disks\n");
		disable_devs |= XMI_UNPLUG_IDE_DISKS;
	}
	if (xen_disable_pv_nics == 0) {
		if (bootverbose)
			printf("XEN: disabling emulated nics\n");
		disable_devs |= XMI_UNPLUG_NICS;
	}

	if (disable_devs != 0)
		outw(XEN_MAGIC_IOPORT, disable_devs);
}

static void
xen_hvm_init_shared_info_page(void)
{
	struct xen_add_to_physmap xatp;

	if (xen_pv_domain()) {
		/*
		 * Already setup in the PV case, shared_info is passed inside
		 * of the start_info struct at start of day.
		 */
		return;
	}

	if (HYPERVISOR_shared_info == NULL) {
		HYPERVISOR_shared_info = malloc(PAGE_SIZE, M_XENHVM, M_NOWAIT);
		if (HYPERVISOR_shared_info == NULL)
			panic("Unable to allocate Xen shared info page");
	}

	xatp.domid = DOMID_SELF;
	xatp.idx = 0;
	xatp.space = XENMAPSPACE_shared_info;
	xatp.gpfn = vtophys(HYPERVISOR_shared_info) >> PAGE_SHIFT;
	if (HYPERVISOR_memory_op(XENMEM_add_to_physmap, &xatp))
		panic("HYPERVISOR_memory_op failed");
}

static void __init xen_hvm_guest_init(void)
{
	if (xen_pv_domain())
		return;

	init_hvm_pv_info();

	xen_hvm_init_shared_info();

	xen_panic_handler_init();

	if (xen_feature(XENFEAT_hvm_callback_vector))
		xen_have_vector_callback = 1;

	xen_hvm_smp_init();
	WARN_ON(xen_cpuhp_setup(xen_cpu_up_prepare_hvm, xen_cpu_dead_hvm));
	xen_unplug_emulated_devices();
	x86_init.irqs.intr_init = xen_init_IRQ;
	xen_hvm_init_time_ops();
	xen_hvm_init_mmu_ops();

	if (xen_pvh_domain())
		machine_ops.emergency_restart = xen_emergency_restart;
#ifdef CONFIG_KEXEC_CORE
	machine_ops.shutdown = xen_hvm_shutdown;
	machine_ops.crash_shutdown = xen_hvm_crash_shutdown;
#endif
}

/*
 * pci_xen_swiotlb_detect - set xen_swiotlb to 1 if necessary
 *
 * This returns non-zero if we are forced to use xen_swiotlb (by the boot
 * option).
 */
int __init pci_xen_swiotlb_detect(void)
{

	if (!xen_pv_domain())
		return 0;

	/* If running as PV guest, either iommu=soft, or swiotlb=force will
	 * activate this IOMMU. If running as PV privileged, activate it
	 * irregardless.
	 */
	if ((xen_initial_domain() || swiotlb || swiotlb_force))
		xen_swiotlb = 1;

	/* If we are running under Xen, we MUST disable the native SWIOTLB.
	 * Don't worry about swiotlb_force flag activating the native, as
	 * the 'swiotlb' flag is the only one turning it on. */
	swiotlb = 0;

#ifdef CONFIG_X86_64
	/* pci_swiotlb_detect_4gb turns on native SWIOTLB if no_iommu == 0
	 * (so no iommu=X command line over-writes).
	 * Considering that PV guests do not want the *native SWIOTLB* but
	 * only Xen SWIOTLB it is not useful to us so set no_iommu=1 here.
	 */
	if (max_pfn > MAX_DMA32_PFN)
		no_iommu = 1;
#endif
	return xen_swiotlb;
}

int gnttab_resume(void)
{
	unsigned int max_nr_gframes;

	max_nr_gframes = gnttab_max_grant_frames();
	if (max_nr_gframes < nr_grant_frames)
		return -ENOSYS;

	if (xen_pv_domain())
		return gnttab_map(0, nr_grant_frames - 1);

	if (!shared) {
		shared = ioremap(xen_hvm_resume_frames, PAGE_SIZE * max_nr_gframes);
		if (shared == NULL) {
#ifdef CONFIG_DEBUG_PRINTK
			printk(KERN_WARNING
					"Failed to ioremap gnttab share frames!");
#else
			;
#endif
			return -ENOMEM;
		}
	}

	gnttab_map(0, nr_grant_frames - 1);

	return 0;
}

bool xen_has_pv_devices(void)
{
	if (!xen_domain())
		return false;

	/* PV domains always have them. */
	if (xen_pv_domain())
		return true;

	/* And user has xen_platform_pci=0 set in guest config as
	 * driver did not modify the value. */
	if (xen_platform_pci_unplug == 0)
		return false;

	if (xen_platform_pci_unplug & XEN_UNPLUG_NEVER)
		return false;

	if (xen_platform_pci_unplug & XEN_UNPLUG_ALL)
		return true;

	/* This is an odd one - we are going to run legacy
	 * and PV drivers at the same time. */
	if (xen_platform_pci_unplug & XEN_UNPLUG_UNNECESSARY)
		return true;

	/* And the caller has to follow with xen_pv_{disk,nic}_devices
	 * to be certain which driver can load. */
	return false;
}

static int setup_cpu_watcher(struct notifier_block *notifier,
			      unsigned long event, void *data)
{
	int cpu;
	static struct xenbus_watch cpu_watch = {
		.node = "cpu",
		.callback = handle_vcpu_hotplug_event};

	(void)register_xenbus_watch(&cpu_watch);

	for_each_possible_cpu(cpu) {
		if (vcpu_online(cpu) == 0) {
			(void)cpu_down(cpu);
			set_cpu_present(cpu, false);
		}
	}

	return NOTIFY_DONE;
}

static int __init setup_vcpu_hotplug_event(void)
{
	static struct notifier_block xsn_cpu = {
		.notifier_call = setup_cpu_watcher };

	if (!xen_pv_domain())
		return -ENODEV;

	register_xenstore_notifier(&xsn_cpu);

	return 0;
}

arch_initcall(setup_vcpu_hotplug_event);

int gnttab_resume(void)
{
	unsigned int max_nr_gframes;

	gnttab_request_version();
	max_nr_gframes = gnttab_max_grant_frames();
	if (max_nr_gframes < nr_grant_frames)
		return -ENOSYS;

	if (xen_pv_domain())
		return gnttab_map(0, nr_grant_frames - 1);

	if (gnttab_shared.addr == NULL) {
		gnttab_shared.addr = ioremap(xen_hvm_resume_frames,
						PAGE_SIZE * max_nr_gframes);
		if (gnttab_shared.addr == NULL) {
			printk(KERN_WARNING
					"Failed to ioremap gnttab share frames!");
			return -ENOMEM;
		}
	}

	gnttab_map(0, nr_grant_frames - 1);

	return 0;
}

static uint32_t __init xen_platform_hvm(void)
{
	if (xen_pv_domain() || xen_nopv)
		return 0;

	return xen_cpuid_base();
}

static int xen_register_gsi(u32 gsi, int gsi_override, int triggering, int polarity)
{
	int rc, irq;
	struct physdev_setup_gsi setup_gsi;

	if (!xen_pv_domain())
		return -1;

	printk(KERN_DEBUG "xen: registering gsi %u triggering %d polarity %d\n",
			gsi, triggering, polarity);

	irq = xen_register_pirq(gsi, gsi_override, triggering, true);

	setup_gsi.gsi = gsi;
	setup_gsi.triggering = (triggering == ACPI_EDGE_SENSITIVE ? 0 : 1);
	setup_gsi.polarity = (polarity == ACPI_ACTIVE_HIGH ? 0 : 1);

	rc = HYPERVISOR_physdev_op(PHYSDEVOP_setup_gsi, &setup_gsi);
	if (rc == -EEXIST)
		printk(KERN_INFO "Already setup the GSI :%d\n", gsi);
	else if (rc) {
		printk(KERN_ERR "Failed to setup GSI :%d, err_code:%d\n",
				gsi, rc);
	}

	return irq;
}

static int xen_apic_probe_pv(void)
{
	if (xen_pv_domain())
		return 1;

	return 0;
}

void xen_arch_post_suspend(int cancelled)
{
    if (xen_pv_domain())
        xen_pv_post_suspend(cancelled);
    else
        xen_hvm_post_suspend(cancelled);
}

static int __init xen_hvc_init(void)
{
	struct hvc_struct *hp;
	struct hv_ops *ops;

	if (!xen_pv_domain())
		return -ENODEV;

	if (xen_initial_domain()) {
		ops = &dom0_hvc_ops;
		xencons_irq = bind_virq_to_irq(VIRQ_CONSOLE, 0);
	} else {
		if (!xen_start_info->console.domU.evtchn)
			return -ENODEV;

		ops = &domU_hvc_ops;
		xencons_irq = bind_evtchn_to_irq(xen_start_info->console.domU.evtchn);
	}
	if (xencons_irq < 0)
		xencons_irq = 0; /* NO_IRQ */
	else
		irq_set_noprobe(xencons_irq);

	hp = hvc_alloc(HVC_COOKIE, xencons_irq, ops, 256);
	if (IS_ERR(hp))
		return PTR_ERR(hp);

	hvc = hp;

	console_pfn = mfn_to_pfn(xen_start_info->console.domU.mfn);

	return 0;
}

int arch_gnttab_init(unsigned long nr_shared)
{
	if (!xen_pv_domain())
		return 0;

	return arch_gnttab_valloc(&gnttab_shared_vm_area, nr_shared);
}