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

742 lines
16 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/types.h>
#include <sys/mman.h>
#include <sys/time.h>
#include <machine/atomic.h>
#include <machine/segments.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <err.h>
#include <libgen.h>
#include <unistd.h>
#include <assert.h>
#include <errno.h>
#include <pthread.h>
#include <pthread_np.h>
#include <sysexits.h>
#include <machine/vmm.h>
#include <vmmapi.h>
#include "bhyverun.h"
#include "acpi.h"
#include "inout.h"
#include "dbgport.h"
#include "ioapic.h"
#include "mem.h"
#include "mevent.h"
#include "mptbl.h"
#include "pci_emul.h"
#include "pci_lpc.h"
#include "xmsr.h"
#include "spinup_ap.h"
#include "rtc.h"
#define GUEST_NIO_PORT 0x488 /* guest upcalls via i/o port */
#define VMEXIT_SWITCH 0 /* force vcpu switch in mux mode */
#define VMEXIT_CONTINUE 1 /* continue from next instruction */
#define VMEXIT_RESTART 2 /* restart current instruction */
#define VMEXIT_ABORT 3 /* abort the vm run loop */
#define VMEXIT_RESET 4 /* guest machine has reset */
#define VMEXIT_POWEROFF 5 /* guest machine has powered off */
#define MB (1024UL * 1024)
#define GB (1024UL * MB)
typedef int (*vmexit_handler_t)(struct vmctx *, struct vm_exit *, int *vcpu);
char *vmname;
int guest_ncpus;
static int pincpu = -1;
static int guest_vmexit_on_hlt, guest_vmexit_on_pause;
static int virtio_msix = 1;
static int x2apic_mode = 0; /* default is xAPIC */
static int strictio;
static int strictmsr = 1;
static int acpi;
static char *progname;
static const int BSP = 0;
static int cpumask;
static void vm_loop(struct vmctx *ctx, int vcpu, uint64_t rip);
struct vm_exit vmexit[VM_MAXCPU];
struct bhyvestats {
uint64_t vmexit_bogus;
uint64_t vmexit_bogus_switch;
uint64_t vmexit_hlt;
uint64_t vmexit_pause;
uint64_t vmexit_mtrap;
uint64_t vmexit_inst_emul;
uint64_t cpu_switch_rotate;
uint64_t cpu_switch_direct;
int io_reset;
} stats;
struct mt_vmm_info {
pthread_t mt_thr;
struct vmctx *mt_ctx;
int mt_vcpu;
} mt_vmm_info[VM_MAXCPU];
static void
usage(int code)
{
fprintf(stderr,
"Usage: %s [-aehwAHIPW] [-g <gdb port>] [-s <pci>]\n"
" %*s [-c vcpus] [-p pincpu] [-m mem] [-l <lpc>] <vm>\n"
" -a: local apic is in xAPIC mode (deprecated)\n"
" -A: create an ACPI table\n"
" -g: gdb port\n"
" -c: # cpus (default 1)\n"
" -p: pin vcpu 'n' to host cpu 'pincpu + n'\n"
" -H: vmexit from the guest on hlt\n"
" -P: vmexit from the guest on pause\n"
" -W: force virtio to use single-vector MSI\n"
" -e: exit on unhandled I/O access\n"
" -h: help\n"
" -s: <slot,driver,configinfo> PCI slot config\n"
" -l: LPC device configuration\n"
" -m: memory size in MB\n"
" -w: ignore unimplemented MSRs\n"
" -x: local apic is in x2APIC mode\n",
progname, (int)strlen(progname), "");
exit(code);
}
void *
paddr_guest2host(struct vmctx *ctx, uintptr_t gaddr, size_t len)
{
return (vm_map_gpa(ctx, gaddr, len));
}
int
fbsdrun_vmexit_on_pause(void)
{
return (guest_vmexit_on_pause);
}
int
fbsdrun_vmexit_on_hlt(void)
{
return (guest_vmexit_on_hlt);
}
int
fbsdrun_virtio_msix(void)
{
return (virtio_msix);
}
static void *
fbsdrun_start_thread(void *param)
{
char tname[MAXCOMLEN + 1];
struct mt_vmm_info *mtp;
int vcpu;
mtp = param;
vcpu = mtp->mt_vcpu;
snprintf(tname, sizeof(tname), "vcpu %d", vcpu);
pthread_set_name_np(mtp->mt_thr, tname);
vm_loop(mtp->mt_ctx, vcpu, vmexit[vcpu].rip);
/* not reached */
exit(1);
return (NULL);
}
void
fbsdrun_addcpu(struct vmctx *ctx, int vcpu, uint64_t rip)
{
int error;
if (cpumask & (1 << vcpu)) {
fprintf(stderr, "addcpu: attempting to add existing cpu %d\n",
vcpu);
exit(1);
}
atomic_set_int(&cpumask, 1 << vcpu);
/*
* Set up the vmexit struct to allow execution to start
* at the given RIP
*/
vmexit[vcpu].rip = rip;
vmexit[vcpu].inst_length = 0;
mt_vmm_info[vcpu].mt_ctx = ctx;
mt_vmm_info[vcpu].mt_vcpu = vcpu;
error = pthread_create(&mt_vmm_info[vcpu].mt_thr, NULL,
fbsdrun_start_thread, &mt_vmm_info[vcpu]);
assert(error == 0);
}
static int
fbsdrun_deletecpu(struct vmctx *ctx, int vcpu)
{
if ((cpumask & (1 << vcpu)) == 0) {
fprintf(stderr, "addcpu: attempting to delete unknown cpu %d\n",
vcpu);
exit(1);
}
atomic_clear_int(&cpumask, 1 << vcpu);
return (cpumask == 0);
}
static int
vmexit_catch_reset(void)
{
stats.io_reset++;
return (VMEXIT_RESET);
}
static int
vmexit_catch_inout(void)
{
return (VMEXIT_ABORT);
}
static int
vmexit_handle_notify(struct vmctx *ctx, struct vm_exit *vme, int *pvcpu,
uint32_t eax)
{
#if BHYVE_DEBUG
/*
* put guest-driven debug here
*/
#endif
return (VMEXIT_CONTINUE);
}
static int
vmexit_inout(struct vmctx *ctx, struct vm_exit *vme, int *pvcpu)
{
int error;
int bytes, port, in, out;
uint32_t eax;
int vcpu;
vcpu = *pvcpu;
port = vme->u.inout.port;
bytes = vme->u.inout.bytes;
eax = vme->u.inout.eax;
in = vme->u.inout.in;
out = !in;
/* We don't deal with these */
if (vme->u.inout.string || vme->u.inout.rep)
return (VMEXIT_ABORT);
/* Special case of guest reset */
if (out && port == 0x64 && (uint8_t)eax == 0xFE)
return (vmexit_catch_reset());
/* Extra-special case of host notifications */
if (out && port == GUEST_NIO_PORT)
return (vmexit_handle_notify(ctx, vme, pvcpu, eax));
error = emulate_inout(ctx, vcpu, in, port, bytes, &eax, strictio);
if (error == INOUT_OK && in)
error = vm_set_register(ctx, vcpu, VM_REG_GUEST_RAX, eax);
switch (error) {
case INOUT_OK:
return (VMEXIT_CONTINUE);
case INOUT_RESET:
return (VMEXIT_RESET);
case INOUT_POWEROFF:
return (VMEXIT_POWEROFF);
default:
fprintf(stderr, "Unhandled %s%c 0x%04x\n",
in ? "in" : "out",
bytes == 1 ? 'b' : (bytes == 2 ? 'w' : 'l'), port);
return (vmexit_catch_inout());
}
}
static int
vmexit_rdmsr(struct vmctx *ctx, struct vm_exit *vme, int *pvcpu)
{
uint64_t val;
uint32_t eax, edx;
int error;
val = 0;
error = emulate_rdmsr(ctx, *pvcpu, vme->u.msr.code, &val);
if (error != 0) {
fprintf(stderr, "rdmsr to register %#x on vcpu %d\n",
vme->u.msr.code, *pvcpu);
if (strictmsr)
return (VMEXIT_ABORT);
}
eax = val;
error = vm_set_register(ctx, *pvcpu, VM_REG_GUEST_RAX, eax);
assert(error == 0);
edx = val >> 32;
error = vm_set_register(ctx, *pvcpu, VM_REG_GUEST_RDX, edx);
assert(error == 0);
return (VMEXIT_CONTINUE);
}
static int
vmexit_wrmsr(struct vmctx *ctx, struct vm_exit *vme, int *pvcpu)
{
int error;
error = emulate_wrmsr(ctx, *pvcpu, vme->u.msr.code, vme->u.msr.wval);
if (error != 0) {
fprintf(stderr, "wrmsr to register %#x(%#lx) on vcpu %d\n",
vme->u.msr.code, vme->u.msr.wval, *pvcpu);
if (strictmsr)
return (VMEXIT_ABORT);
}
return (VMEXIT_CONTINUE);
}
static int
vmexit_spinup_ap(struct vmctx *ctx, struct vm_exit *vme, int *pvcpu)
{
int newcpu;
int retval = VMEXIT_CONTINUE;
newcpu = spinup_ap(ctx, *pvcpu,
vme->u.spinup_ap.vcpu, vme->u.spinup_ap.rip);
return (retval);
}
static int
vmexit_spindown_cpu(struct vmctx *ctx, struct vm_exit *vme, int *pvcpu)
{
int lastcpu;
lastcpu = fbsdrun_deletecpu(ctx, *pvcpu);
if (!lastcpu)
pthread_exit(NULL);
return (vmexit_catch_reset());
}
static int
vmexit_vmx(struct vmctx *ctx, struct vm_exit *vmexit, int *pvcpu)
{
fprintf(stderr, "vm exit[%d]\n", *pvcpu);
fprintf(stderr, "\treason\t\tVMX\n");
fprintf(stderr, "\trip\t\t0x%016lx\n", vmexit->rip);
fprintf(stderr, "\tinst_length\t%d\n", vmexit->inst_length);
fprintf(stderr, "\tstatus\t\t%d\n", vmexit->u.vmx.status);
fprintf(stderr, "\texit_reason\t%u\n", vmexit->u.vmx.exit_reason);
fprintf(stderr, "\tqualification\t0x%016lx\n",
vmexit->u.vmx.exit_qualification);
fprintf(stderr, "\tinst_type\t\t%d\n", vmexit->u.vmx.inst_type);
fprintf(stderr, "\tinst_error\t\t%d\n", vmexit->u.vmx.inst_error);
return (VMEXIT_ABORT);
}
static int
vmexit_bogus(struct vmctx *ctx, struct vm_exit *vmexit, int *pvcpu)
{
stats.vmexit_bogus++;
return (VMEXIT_RESTART);
}
static int
vmexit_hlt(struct vmctx *ctx, struct vm_exit *vmexit, int *pvcpu)
{
stats.vmexit_hlt++;
/*
* Just continue execution with the next instruction. We use
* the HLT VM exit as a way to be friendly with the host
* scheduler.
*/
return (VMEXIT_CONTINUE);
}
static int
vmexit_pause(struct vmctx *ctx, struct vm_exit *vmexit, int *pvcpu)
{
stats.vmexit_pause++;
return (VMEXIT_CONTINUE);
}
static int
vmexit_mtrap(struct vmctx *ctx, struct vm_exit *vmexit, int *pvcpu)
{
stats.vmexit_mtrap++;
return (VMEXIT_RESTART);
}
static int
vmexit_inst_emul(struct vmctx *ctx, struct vm_exit *vmexit, int *pvcpu)
{
int err;
stats.vmexit_inst_emul++;
err = emulate_mem(ctx, *pvcpu, vmexit->u.inst_emul.gpa,
&vmexit->u.inst_emul.vie);
if (err) {
if (err == EINVAL) {
fprintf(stderr,
"Failed to emulate instruction at 0x%lx\n",
vmexit->rip);
} else if (err == ESRCH) {
fprintf(stderr, "Unhandled memory access to 0x%lx\n",
vmexit->u.inst_emul.gpa);
}
return (VMEXIT_ABORT);
}
return (VMEXIT_CONTINUE);
}
static vmexit_handler_t handler[VM_EXITCODE_MAX] = {
[VM_EXITCODE_INOUT] = vmexit_inout,
[VM_EXITCODE_VMX] = vmexit_vmx,
[VM_EXITCODE_BOGUS] = vmexit_bogus,
[VM_EXITCODE_RDMSR] = vmexit_rdmsr,
[VM_EXITCODE_WRMSR] = vmexit_wrmsr,
[VM_EXITCODE_MTRAP] = vmexit_mtrap,
[VM_EXITCODE_INST_EMUL] = vmexit_inst_emul,
[VM_EXITCODE_SPINUP_AP] = vmexit_spinup_ap,
[VM_EXITCODE_SPINDOWN_CPU] = vmexit_spindown_cpu,
};
static void
vm_loop(struct vmctx *ctx, int vcpu, uint64_t rip)
{
cpuset_t mask;
int error, rc, prevcpu;
enum vm_exitcode exitcode;
if (pincpu >= 0) {
CPU_ZERO(&mask);
CPU_SET(pincpu + vcpu, &mask);
error = pthread_setaffinity_np(pthread_self(),
sizeof(mask), &mask);
assert(error == 0);
}
while (1) {
error = vm_run(ctx, vcpu, rip, &vmexit[vcpu]);
if (error != 0)
break;
prevcpu = vcpu;
exitcode = vmexit[vcpu].exitcode;
if (exitcode >= VM_EXITCODE_MAX || handler[exitcode] == NULL) {
fprintf(stderr, "vm_loop: unexpected exitcode 0x%x\n",
exitcode);
exit(1);
}
rc = (*handler[exitcode])(ctx, &vmexit[vcpu], &vcpu);
switch (rc) {
case VMEXIT_CONTINUE:
rip = vmexit[vcpu].rip + vmexit[vcpu].inst_length;
break;
case VMEXIT_RESTART:
rip = vmexit[vcpu].rip;
break;
case VMEXIT_RESET:
exit(0);
default:
exit(1);
}
}
fprintf(stderr, "vm_run error %d, errno %d\n", error, errno);
}
static int
num_vcpus_allowed(struct vmctx *ctx)
{
int tmp, error;
error = vm_get_capability(ctx, BSP, VM_CAP_UNRESTRICTED_GUEST, &tmp);
/*
* The guest is allowed to spinup more than one processor only if the
* UNRESTRICTED_GUEST capability is available.
*/
if (error == 0)
return (VM_MAXCPU);
else
return (1);
}
void
fbsdrun_set_capabilities(struct vmctx *ctx, int cpu)
{
int err, tmp;
if (fbsdrun_vmexit_on_hlt()) {
err = vm_get_capability(ctx, cpu, VM_CAP_HALT_EXIT, &tmp);
if (err < 0) {
fprintf(stderr, "VM exit on HLT not supported\n");
exit(1);
}
vm_set_capability(ctx, cpu, VM_CAP_HALT_EXIT, 1);
if (cpu == BSP)
handler[VM_EXITCODE_HLT] = vmexit_hlt;
}
if (fbsdrun_vmexit_on_pause()) {
/*
* pause exit support required for this mode
*/
err = vm_get_capability(ctx, cpu, VM_CAP_PAUSE_EXIT, &tmp);
if (err < 0) {
fprintf(stderr,
"SMP mux requested, no pause support\n");
exit(1);
}
vm_set_capability(ctx, cpu, VM_CAP_PAUSE_EXIT, 1);
if (cpu == BSP)
handler[VM_EXITCODE_PAUSE] = vmexit_pause;
}
if (x2apic_mode)
err = vm_set_x2apic_state(ctx, cpu, X2APIC_ENABLED);
else
err = vm_set_x2apic_state(ctx, cpu, X2APIC_DISABLED);
if (err) {
fprintf(stderr, "Unable to set x2apic state (%d)\n", err);
exit(1);
}
vm_set_capability(ctx, cpu, VM_CAP_ENABLE_INVPCID, 1);
}
int
main(int argc, char *argv[])
{
int c, error, gdb_port, err, bvmcons;
int max_vcpus;
struct vmctx *ctx;
uint64_t rip;
size_t memsize;
bvmcons = 0;
progname = basename(argv[0]);
gdb_port = 0;
guest_ncpus = 1;
memsize = 256 * MB;
while ((c = getopt(argc, argv, "abehwxAHIPWp:g:c:s:m:l:")) != -1) {
switch (c) {
case 'a':
x2apic_mode = 0;
break;
case 'A':
acpi = 1;
break;
case 'b':
bvmcons = 1;
break;
case 'p':
pincpu = atoi(optarg);
break;
case 'c':
guest_ncpus = atoi(optarg);
break;
case 'g':
gdb_port = atoi(optarg);
break;
case 'l':
if (lpc_device_parse(optarg) != 0) {
errx(EX_USAGE, "invalid lpc device "
"configuration '%s'", optarg);
}
break;
case 's':
if (pci_parse_slot(optarg) != 0)
exit(1);
else
break;
case 'm':
error = vm_parse_memsize(optarg, &memsize);
if (error)
errx(EX_USAGE, "invalid memsize '%s'", optarg);
break;
case 'H':
guest_vmexit_on_hlt = 1;
break;
case 'I':
/*
* The "-I" option was used to add an ioapic to the
* virtual machine.
*
* An ioapic is now provided unconditionally for each
* virtual machine and this option is now deprecated.
*/
break;
case 'P':
guest_vmexit_on_pause = 1;
break;
case 'e':
strictio = 1;
break;
case 'w':
strictmsr = 0;
break;
case 'W':
virtio_msix = 0;
break;
case 'x':
x2apic_mode = 1;
break;
case 'h':
usage(0);
default:
usage(1);
}
}
argc -= optind;
argv += optind;
if (argc != 1)
usage(1);
vmname = argv[0];
ctx = vm_open(vmname);
if (ctx == NULL) {
perror("vm_open");
exit(1);
}
max_vcpus = num_vcpus_allowed(ctx);
if (guest_ncpus > max_vcpus) {
fprintf(stderr, "%d vCPUs requested but only %d available\n",
guest_ncpus, max_vcpus);
exit(1);
}
fbsdrun_set_capabilities(ctx, BSP);
err = vm_setup_memory(ctx, memsize, VM_MMAP_ALL);
if (err) {
fprintf(stderr, "Unable to setup memory (%d)\n", err);
exit(1);
}
init_mem();
init_inout();
ioapic_init(ctx);
rtc_init(ctx);
/*
* Exit if a device emulation finds an error in it's initilization
*/
if (init_pci(ctx) != 0)
exit(1);
if (gdb_port != 0)
init_dbgport(gdb_port);
if (bvmcons)
init_bvmcons();
error = vm_get_register(ctx, BSP, VM_REG_GUEST_RIP, &rip);
assert(error == 0);
/*
* build the guest tables, MP etc.
*/
mptable_build(ctx, guest_ncpus);
if (acpi) {
error = acpi_build(ctx, guest_ncpus);
assert(error == 0);
}
/*
* Change the proc title to include the VM name.
*/
setproctitle("%s", vmname);
/*
* Add CPU 0
*/
fbsdrun_addcpu(ctx, BSP, rip);
/*
* Head off to the main event dispatch loop
*/
mevent_dispatch();
exit(1);
}