/*-
* SPDX-License-Identifier: BSD-2-Clause
*
* Copyright (c) 2008, 2013 Citrix Systems, Inc.
* Copyright (c) 2012 Spectra Logic Corporation
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
#include <sys/param.h>
#include <sys/bus.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/proc.h>
#include <sys/smp.h>
#include <sys/systm.h>
#include <vm/vm.h>
#include <vm/pmap.h>
#include <vm/vm_param.h>
#include <dev/pci/pcivar.h>
#include <machine/cpufunc.h>
#include <machine/cpu.h>
#include <machine/smp.h>
#include <x86/apicreg.h>
#include <xen/xen-os.h>
#include <xen/error.h>
#include <xen/features.h>
#include <xen/gnttab.h>
#include <xen/hypervisor.h>
#include <xen/hvm.h>
#include <xen/xen_intr.h>
#include <contrib/xen/arch-x86/cpuid.h>
#include <contrib/xen/hvm/params.h>
#include <contrib/xen/vcpu.h>
/*--------------------------- Forward Declarations ---------------------------*/
static void xen_hvm_cpu_init(void);
/*-------------------------------- Global Data -------------------------------*/
#ifdef SMP
struct cpu_ops xen_hvm_cpu_ops = {
.cpu_init = xen_hvm_cpu_init,
.cpu_resume = xen_hvm_cpu_init
};
#endif
static MALLOC_DEFINE(M_XENHVM, "xen_hvm", "Xen HVM PV Support");
/**
* If non-zero, the hypervisor has been configured to use a direct
* IDT event callback for interrupt injection.
*/
int xen_vector_callback_enabled;
/**
* Signal whether the vector injected for the event channel upcall requires to
* be EOI'ed on the local APIC.
*/
bool xen_evtchn_needs_ack;
/*------------------------------- Per-CPU Data -------------------------------*/
DPCPU_DECLARE(struct vcpu_info *, vcpu_info);
/*------------------------------ Sysctl tunables -----------------------------*/
int xen_disable_pv_disks = 0;
int xen_disable_pv_nics = 0;
TUNABLE_INT("hw.xen.disable_pv_disks", &xen_disable_pv_disks);
TUNABLE_INT("hw.xen.disable_pv_nics", &xen_disable_pv_nics);
/*---------------------- XEN Hypervisor Probe and Setup ----------------------*/
uint32_t xen_cpuid_base;
static uint32_t
xen_hvm_cpuid_base(void)
{
uint32_t base, regs[4];
for (base = 0x40000000; base < 0x40010000; base += 0x100) {
do_cpuid(base, regs);
if (!memcmp("XenVMMXenVMM", ®s[1], 12)
&& (regs[0] - base) >= 2)
return (base);
}
return (0);
}
static void
hypervisor_quirks(unsigned int major, unsigned int minor)
{
#ifdef SMP
if (((major < 4) || (major == 4 && minor <= 5)) &&
msix_disable_migration == -1) {
/*
* Xen hypervisors prior to 4.6.0 do not properly
* handle updates to enabled MSI-X table entries,
* so disable MSI-X interrupt migration in that
* case.
*/
if (bootverbose)
printf(
"Disabling MSI-X interrupt migration due to Xen hypervisor bug.\n"
"Set machdep.msix_disable_migration=0 to forcefully enable it.\n");
msix_disable_migration = 1;
}
#endif
}
static void
hypervisor_version(void)
{
uint32_t regs[4];
int major, minor;
do_cpuid(xen_cpuid_base + 1, regs);
major = regs[0] >> 16;
minor = regs[0] & 0xffff;
printf("XEN: Hypervisor version %d.%d detected.\n", major, minor);
hypervisor_quirks(major, minor);
}
/*
* Allocate and fill in the hypcall page.
*/
int
xen_hvm_init_hypercall_stubs(enum xen_hvm_init_type init_type)
{
uint32_t regs[4];
/* Legacy PVH will get here without the cpuid leaf being set. */
if (xen_cpuid_base == 0)
xen_cpuid_base = xen_hvm_cpuid_base();
if (xen_cpuid_base == 0)
return (ENXIO);
if (xen_domain() && init_type == XEN_HVM_INIT_LATE) {
/*
* If the domain type is already set we can assume that the
* hypercall page has been populated too, so just print the
* version (and apply any quirks) and exit.
*/
hypervisor_version();
return 0;
}
if (init_type == XEN_HVM_INIT_LATE)
hypervisor_version();
/*
* Find the hypercall pages.
*/
do_cpuid(xen_cpuid_base + 2, regs);
if (regs[0] != 1)
return (EINVAL);
wrmsr(regs[1], (init_type == XEN_HVM_INIT_EARLY)
? (vm_paddr_t)((uintptr_t)&hypercall_page - KERNBASE)
: vtophys(&hypercall_page));
return (0);
}
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 int
set_percpu_callback(unsigned int vcpu)
{
struct xen_hvm_evtchn_upcall_vector vec;
int error;
vec.vcpu = vcpu;
vec.vector = IDT_EVTCHN;
error = HYPERVISOR_hvm_op(HVMOP_set_evtchn_upcall_vector, &vec);
return (error != 0 ? xen_translate_error(error) : 0);
}
/*
* Tell the hypervisor how to contact us for event channel callbacks.
*/
void
xen_hvm_set_callback(device_t dev)
{
struct xen_hvm_param xhp;
int irq;
if (xen_vector_callback_enabled)
return;
xhp.domid = DOMID_SELF;
xhp.index = HVM_PARAM_CALLBACK_IRQ;
if (xen_feature(XENFEAT_hvm_callback_vector) != 0) {
int error;
error = set_percpu_callback(0);
if (error == 0) {
xen_evtchn_needs_ack = true;
/* Trick toolstack to think we are enlightened */
xhp.value = 1;
} else
xhp.value = HVM_CALLBACK_VECTOR(IDT_EVTCHN);
error = HYPERVISOR_hvm_op(HVMOP_set_param, &xhp);
if (error == 0) {
xen_vector_callback_enabled = 1;
return;
} else if (xen_evtchn_needs_ack)
panic("Unable to setup fake HVM param: %d", error);
printf("Xen HVM callback vector registration failed (%d). "
"Falling back to emulated device interrupt\n", error);
}
xen_vector_callback_enabled = 0;
if (dev == NULL) {
/*
* Called from early boot or resume.
* xenpci will invoke us again later.
*/
return;
}
irq = pci_get_irq(dev);
if (irq < 16) {
xhp.value = HVM_CALLBACK_GSI(irq);
} else {
u_int slot;
u_int pin;
slot = pci_get_slot(dev);
pin = pci_get_intpin(dev) - 1;
xhp.value = HVM_CALLBACK_PCI_INTX(slot, pin);
}
if (HYPERVISOR_hvm_op(HVMOP_set_param, &xhp) != 0)
panic("Can't set evtchn callback");
}
#define XEN_MAGIC_IOPORT 0x10
enum {
XMI_MAGIC = 0x49d2,
XMI_UNPLUG_IDE_DISKS = 0x01,
XMI_UNPLUG_NICS = 0x02,
XMI_UNPLUG_IDE_EXCEPT_PRI_MASTER = 0x04
};
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(enum xen_hvm_init_type init_type)
{
int error;
int i;
if (init_type == XEN_HVM_INIT_CANCELLED_SUSPEND)
return;
error = xen_hvm_init_hypercall_stubs(init_type);
switch (init_type) {
case XEN_HVM_INIT_LATE:
if (error != 0)
return;
/*
* If xen_domain_type is not set at this point
* it means we are inside a (PV)HVM guest, because
* for PVH the guest type is set much earlier
* (see hammer_time_xen).
*/
if (!xen_domain()) {
xen_domain_type = XEN_HVM_DOMAIN;
vm_guest = VM_GUEST_XEN;
}
setup_xen_features();
#ifdef SMP
cpu_ops = xen_hvm_cpu_ops;
#endif
break;
case XEN_HVM_INIT_RESUME:
if (error != 0)
panic("Unable to init Xen hypercall stubs on resume");
/* Clear stale vcpu_info. */
CPU_FOREACH(i)
DPCPU_ID_SET(i, vcpu_info, NULL);
break;
default:
panic("Unsupported HVM initialization type");
}
xen_vector_callback_enabled = 0;
xen_evtchn_needs_ack = false;
xen_hvm_set_callback(NULL);
/*
* On (PV)HVM domains we need to request the hypervisor to
* fill the shared info page, for PVH guest the shared_info page
* is passed inside the start_info struct and is already set, so this
* functions are no-ops.
*/
xen_hvm_init_shared_info_page();
xen_hvm_disable_emulated_devices();
}
void
xen_hvm_suspend(void)
{
}
void
xen_hvm_resume(bool suspend_cancelled)
{
xen_hvm_init(suspend_cancelled ?
XEN_HVM_INIT_CANCELLED_SUSPEND : XEN_HVM_INIT_RESUME);
/* Register vcpu_info area for CPU#0. */
xen_hvm_cpu_init();
}
static void
xen_hvm_sysinit(void *arg __unused)
{
xen_hvm_init(XEN_HVM_INIT_LATE);
}
SYSINIT(xen_hvm_init, SI_SUB_HYPERVISOR, SI_ORDER_FIRST, xen_hvm_sysinit, NULL);
static void
xen_hvm_cpu_init(void)
{
uint32_t regs[4];
int rc;
if (!xen_domain())
return;
if (DPCPU_GET(vcpu_info) != NULL) {
/*
* vcpu_info is already set. We're resuming
* from a failed migration and our pre-suspend
* configuration is still valid.
*/
return;
}
/*
* Set vCPU ID. If available fetch the ID from CPUID, if not just use
* the ACPI ID.
*/
KASSERT(xen_cpuid_base != 0, ("Invalid base Xen CPUID leaf"));
cpuid_count(xen_cpuid_base + 4, 0, regs);
KASSERT((regs[0] & XEN_HVM_CPUID_VCPU_ID_PRESENT) ||
!xen_pv_domain(),
("Xen PV domain without vcpu_id in cpuid"));
PCPU_SET(vcpu_id, (regs[0] & XEN_HVM_CPUID_VCPU_ID_PRESENT) ?
regs[1] : PCPU_GET(acpi_id));
if (xen_evtchn_needs_ack && !IS_BSP()) {
/*
* Setup the per-vpcu event channel upcall vector. This is only
* required when using the new HVMOP_set_evtchn_upcall_vector
* hypercall, which allows using a different vector for each
* vCPU. Note that FreeBSD uses the same vector for all vCPUs
* because it's not dynamically allocated.
*/
rc = set_percpu_callback(PCPU_GET(vcpu_id));
if (rc != 0)
panic("Event channel upcall vector setup failed: %d",
rc);
}
xen_setup_vcpu_info();
}
SYSINIT(xen_hvm_cpu_init, SI_SUB_INTR, SI_ORDER_FIRST, xen_hvm_cpu_init, NULL);
bool
xen_has_iommu_maps(void)
{
uint32_t regs[4];
KASSERT(xen_cpuid_base != 0, ("Invalid base Xen CPUID leaf"));
cpuid_count(xen_cpuid_base + 4, 0, regs);
return (regs[0] & XEN_HVM_CPUID_IOMMU_MAPPINGS);
}
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