freebsd-skq/sys/amd64/vmm/vmm_lapic.c
Neel Natu 52e5c8a2ec Simplify APIC mode switching from MMIO to x2APIC. In part this is done to
simplify the implementation of the x2APIC virtualization assist in VT-x.

Prior to this change the vlapic allowed the guest to change its mode from
xAPIC to x2APIC. We don't allow that any more and the vlapic mode is locked
when the virtual machine is created. This is not very constraining because
operating systems already have to deal with BIOS setting up the APIC in
x2APIC mode at boot.

Fix a bug in the CPUID emulation where the x2APIC capability was leaking
from the host to the guest.

Ignore MMIO reads and writes to the vlapic in x2APIC mode. Similarly, ignore
MSR accesses to the vlapic when it is in xAPIC mode.

The default configuration of the vlapic is xAPIC. The "-x" option to bhyve(8)
can be used to change the mode to x2APIC instead.

Discussed with:	grehan@
2014-02-20 01:48:25 +00:00

243 lines
5.5 KiB
C

/*-
* Copyright (c) 2011 NetApp, Inc.
* 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 NETAPP, INC ``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 NETAPP, INC 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.
*
* $FreeBSD$
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/smp.h>
#include <x86/specialreg.h>
#include <x86/apicreg.h>
#include <machine/vmm.h>
#include "vmm_ipi.h"
#include "vmm_ktr.h"
#include "vmm_lapic.h"
#include "vlapic.h"
/*
* Some MSI message definitions
*/
#define MSI_X86_ADDR_MASK 0xfff00000
#define MSI_X86_ADDR_BASE 0xfee00000
#define MSI_X86_ADDR_RH 0x00000008 /* Redirection Hint */
#define MSI_X86_ADDR_LOG 0x00000004 /* Destination Mode */
int
lapic_set_intr(struct vm *vm, int cpu, int vector, bool level)
{
struct vlapic *vlapic;
if (cpu < 0 || cpu >= VM_MAXCPU)
return (EINVAL);
if (vector < 32 || vector > 255)
return (EINVAL);
vlapic = vm_lapic(vm, cpu);
if (vlapic_set_intr_ready(vlapic, vector, level))
vcpu_notify_event(vm, cpu, true);
return (0);
}
int
lapic_set_local_intr(struct vm *vm, int cpu, int vector)
{
struct vlapic *vlapic;
cpuset_t dmask;
int error;
if (cpu < -1 || cpu >= VM_MAXCPU)
return (EINVAL);
if (cpu == -1)
dmask = vm_active_cpus(vm);
else
CPU_SETOF(cpu, &dmask);
error = 0;
while ((cpu = CPU_FFS(&dmask)) != 0) {
cpu--;
CPU_CLR(cpu, &dmask);
vlapic = vm_lapic(vm, cpu);
error = vlapic_trigger_lvt(vlapic, vector);
if (error)
break;
}
return (error);
}
int
lapic_intr_msi(struct vm *vm, uint64_t addr, uint64_t msg)
{
int delmode, vec;
uint32_t dest;
bool phys;
VM_CTR2(vm, "lapic MSI addr: %#lx msg: %#lx", addr, msg);
if ((addr & MSI_X86_ADDR_MASK) != MSI_X86_ADDR_BASE) {
VM_CTR1(vm, "lapic MSI invalid addr %#lx", addr);
return (-1);
}
/*
* Extract the x86-specific fields from the MSI addr/msg
* params according to the Intel Arch spec, Vol3 Ch 10.
*
* The PCI specification does not support level triggered
* MSI/MSI-X so ignore trigger level in 'msg'.
*
* The 'dest' is interpreted as a logical APIC ID if both
* the Redirection Hint and Destination Mode are '1' and
* physical otherwise.
*/
dest = (addr >> 12) & 0xff;
phys = ((addr & (MSI_X86_ADDR_RH | MSI_X86_ADDR_LOG)) !=
(MSI_X86_ADDR_RH | MSI_X86_ADDR_LOG));
delmode = msg & APIC_DELMODE_MASK;
vec = msg & 0xff;
VM_CTR3(vm, "lapic MSI %s dest %#x, vec %d",
phys ? "physical" : "logical", dest, vec);
vlapic_deliver_intr(vm, LAPIC_TRIG_EDGE, dest, phys, delmode, vec);
return (0);
}
static boolean_t
x2apic_msr(u_int msr)
{
if (msr >= 0x800 && msr <= 0xBFF)
return (TRUE);
else
return (FALSE);
}
static u_int
x2apic_msr_to_regoff(u_int msr)
{
return ((msr - 0x800) << 4);
}
boolean_t
lapic_msr(u_int msr)
{
if (x2apic_msr(msr) || (msr == MSR_APICBASE))
return (TRUE);
else
return (FALSE);
}
int
lapic_rdmsr(struct vm *vm, int cpu, u_int msr, uint64_t *rval, bool *retu)
{
int error;
u_int offset;
struct vlapic *vlapic;
vlapic = vm_lapic(vm, cpu);
if (msr == MSR_APICBASE) {
*rval = vlapic_get_apicbase(vlapic);
error = 0;
} else {
offset = x2apic_msr_to_regoff(msr);
error = vlapic_read(vlapic, 0, offset, rval, retu);
}
return (error);
}
int
lapic_wrmsr(struct vm *vm, int cpu, u_int msr, uint64_t val, bool *retu)
{
int error;
u_int offset;
struct vlapic *vlapic;
vlapic = vm_lapic(vm, cpu);
if (msr == MSR_APICBASE) {
error = vlapic_set_apicbase(vlapic, val);
} else {
offset = x2apic_msr_to_regoff(msr);
error = vlapic_write(vlapic, 0, offset, val, retu);
}
return (error);
}
int
lapic_mmio_write(void *vm, int cpu, uint64_t gpa, uint64_t wval, int size,
void *arg)
{
int error;
uint64_t off;
struct vlapic *vlapic;
off = gpa - DEFAULT_APIC_BASE;
/*
* Memory mapped local apic accesses must be 4 bytes wide and
* aligned on a 16-byte boundary.
*/
if (size != 4 || off & 0xf)
return (EINVAL);
vlapic = vm_lapic(vm, cpu);
error = vlapic_write(vlapic, 1, off, wval, arg);
return (error);
}
int
lapic_mmio_read(void *vm, int cpu, uint64_t gpa, uint64_t *rval, int size,
void *arg)
{
int error;
uint64_t off;
struct vlapic *vlapic;
off = gpa - DEFAULT_APIC_BASE;
/*
* Memory mapped local apic accesses must be 4 bytes wide and
* aligned on a 16-byte boundary.
*/
if (size != 4 || off & 0xf)
return (EINVAL);
vlapic = vm_lapic(vm, cpu);
error = vlapic_read(vlapic, 1, off, rval, arg);
return (error);
}