freebsd-dev/sys/amd64/vmm/vmm_dev.c
Neel Natu 091d453222 Handle nested exceptions in bhyve.
A nested exception condition arises when a second exception is triggered while
delivering the first exception. Most nested exceptions can be handled serially
but some are converted into a double fault. If an exception is generated during
delivery of a double fault then the virtual machine shuts down as a result of
a triple fault.

vm_exit_intinfo() is used to record that a VM-exit happened while an event was
being delivered through the IDT. If an exception is triggered while handling
the VM-exit it will be treated like a nested exception.

vm_entry_intinfo() is used by processor-specific code to get the event to be
injected into the guest on the next VM-entry. This function is responsible for
deciding the disposition of nested exceptions.
2014-07-19 20:59:08 +00:00

672 lines
17 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/kernel.h>
#include <sys/queue.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/malloc.h>
#include <sys/conf.h>
#include <sys/sysctl.h>
#include <sys/libkern.h>
#include <sys/ioccom.h>
#include <sys/mman.h>
#include <sys/uio.h>
#include <vm/vm.h>
#include <vm/pmap.h>
#include <vm/vm_map.h>
#include <machine/vmparam.h>
#include <machine/vmm.h>
#include <machine/vmm_instruction_emul.h>
#include <machine/vmm_dev.h>
#include "vmm_lapic.h"
#include "vmm_stat.h"
#include "vmm_mem.h"
#include "io/ppt.h"
#include "io/vatpic.h"
#include "io/vioapic.h"
#include "io/vhpet.h"
struct vmmdev_softc {
struct vm *vm; /* vm instance cookie */
struct cdev *cdev;
SLIST_ENTRY(vmmdev_softc) link;
int flags;
};
#define VSC_LINKED 0x01
static SLIST_HEAD(, vmmdev_softc) head;
static struct mtx vmmdev_mtx;
static MALLOC_DEFINE(M_VMMDEV, "vmmdev", "vmmdev");
SYSCTL_DECL(_hw_vmm);
static struct vmmdev_softc *
vmmdev_lookup(const char *name)
{
struct vmmdev_softc *sc;
#ifdef notyet /* XXX kernel is not compiled with invariants */
mtx_assert(&vmmdev_mtx, MA_OWNED);
#endif
SLIST_FOREACH(sc, &head, link) {
if (strcmp(name, vm_name(sc->vm)) == 0)
break;
}
return (sc);
}
static struct vmmdev_softc *
vmmdev_lookup2(struct cdev *cdev)
{
return (cdev->si_drv1);
}
static int
vmmdev_rw(struct cdev *cdev, struct uio *uio, int flags)
{
int error, off, c, prot;
vm_paddr_t gpa;
void *hpa, *cookie;
struct vmmdev_softc *sc;
static char zerobuf[PAGE_SIZE];
error = 0;
sc = vmmdev_lookup2(cdev);
if (sc == NULL)
error = ENXIO;
prot = (uio->uio_rw == UIO_WRITE ? VM_PROT_WRITE : VM_PROT_READ);
while (uio->uio_resid > 0 && error == 0) {
gpa = uio->uio_offset;
off = gpa & PAGE_MASK;
c = min(uio->uio_resid, PAGE_SIZE - off);
/*
* The VM has a hole in its physical memory map. If we want to
* use 'dd' to inspect memory beyond the hole we need to
* provide bogus data for memory that lies in the hole.
*
* Since this device does not support lseek(2), dd(1) will
* read(2) blocks of data to simulate the lseek(2).
*/
hpa = vm_gpa_hold(sc->vm, gpa, c, prot, &cookie);
if (hpa == NULL) {
if (uio->uio_rw == UIO_READ)
error = uiomove(zerobuf, c, uio);
else
error = EFAULT;
} else {
error = uiomove(hpa, c, uio);
vm_gpa_release(cookie);
}
}
return (error);
}
static int
vmmdev_ioctl(struct cdev *cdev, u_long cmd, caddr_t data, int fflag,
struct thread *td)
{
int error, vcpu, state_changed, size;
cpuset_t *cpuset;
struct vmmdev_softc *sc;
struct vm_memory_segment *seg;
struct vm_register *vmreg;
struct vm_seg_desc *vmsegdesc;
struct vm_run *vmrun;
struct vm_exception *vmexc;
struct vm_lapic_irq *vmirq;
struct vm_lapic_msi *vmmsi;
struct vm_ioapic_irq *ioapic_irq;
struct vm_isa_irq *isa_irq;
struct vm_isa_irq_trigger *isa_irq_trigger;
struct vm_capability *vmcap;
struct vm_pptdev *pptdev;
struct vm_pptdev_mmio *pptmmio;
struct vm_pptdev_msi *pptmsi;
struct vm_pptdev_msix *pptmsix;
struct vm_nmi *vmnmi;
struct vm_stats *vmstats;
struct vm_stat_desc *statdesc;
struct vm_x2apic *x2apic;
struct vm_gpa_pte *gpapte;
struct vm_suspend *vmsuspend;
struct vm_gla2gpa *gg;
struct vm_activate_cpu *vac;
struct vm_cpuset *vm_cpuset;
struct vm_intinfo *vmii;
sc = vmmdev_lookup2(cdev);
if (sc == NULL)
return (ENXIO);
error = 0;
vcpu = -1;
state_changed = 0;
/*
* Some VMM ioctls can operate only on vcpus that are not running.
*/
switch (cmd) {
case VM_RUN:
case VM_GET_REGISTER:
case VM_SET_REGISTER:
case VM_GET_SEGMENT_DESCRIPTOR:
case VM_SET_SEGMENT_DESCRIPTOR:
case VM_INJECT_EXCEPTION:
case VM_GET_CAPABILITY:
case VM_SET_CAPABILITY:
case VM_PPTDEV_MSI:
case VM_PPTDEV_MSIX:
case VM_SET_X2APIC_STATE:
case VM_GLA2GPA:
case VM_ACTIVATE_CPU:
case VM_SET_INTINFO:
case VM_GET_INTINFO:
/*
* XXX fragile, handle with care
* Assumes that the first field of the ioctl data is the vcpu.
*/
vcpu = *(int *)data;
if (vcpu < 0 || vcpu >= VM_MAXCPU) {
error = EINVAL;
goto done;
}
error = vcpu_set_state(sc->vm, vcpu, VCPU_FROZEN, true);
if (error)
goto done;
state_changed = 1;
break;
case VM_MAP_PPTDEV_MMIO:
case VM_BIND_PPTDEV:
case VM_UNBIND_PPTDEV:
case VM_MAP_MEMORY:
case VM_REINIT:
/*
* ioctls that operate on the entire virtual machine must
* prevent all vcpus from running.
*/
error = 0;
for (vcpu = 0; vcpu < VM_MAXCPU; vcpu++) {
error = vcpu_set_state(sc->vm, vcpu, VCPU_FROZEN, true);
if (error)
break;
}
if (error) {
while (--vcpu >= 0)
vcpu_set_state(sc->vm, vcpu, VCPU_IDLE, false);
goto done;
}
state_changed = 2;
break;
default:
break;
}
switch(cmd) {
case VM_RUN:
vmrun = (struct vm_run *)data;
error = vm_run(sc->vm, vmrun);
break;
case VM_SUSPEND:
vmsuspend = (struct vm_suspend *)data;
error = vm_suspend(sc->vm, vmsuspend->how);
break;
case VM_REINIT:
error = vm_reinit(sc->vm);
break;
case VM_STAT_DESC: {
statdesc = (struct vm_stat_desc *)data;
error = vmm_stat_desc_copy(statdesc->index,
statdesc->desc, sizeof(statdesc->desc));
break;
}
case VM_STATS: {
CTASSERT(MAX_VM_STATS >= MAX_VMM_STAT_ELEMS);
vmstats = (struct vm_stats *)data;
getmicrotime(&vmstats->tv);
error = vmm_stat_copy(sc->vm, vmstats->cpuid,
&vmstats->num_entries, vmstats->statbuf);
break;
}
case VM_PPTDEV_MSI:
pptmsi = (struct vm_pptdev_msi *)data;
error = ppt_setup_msi(sc->vm, pptmsi->vcpu,
pptmsi->bus, pptmsi->slot, pptmsi->func,
pptmsi->addr, pptmsi->msg,
pptmsi->numvec);
break;
case VM_PPTDEV_MSIX:
pptmsix = (struct vm_pptdev_msix *)data;
error = ppt_setup_msix(sc->vm, pptmsix->vcpu,
pptmsix->bus, pptmsix->slot,
pptmsix->func, pptmsix->idx,
pptmsix->addr, pptmsix->msg,
pptmsix->vector_control);
break;
case VM_MAP_PPTDEV_MMIO:
pptmmio = (struct vm_pptdev_mmio *)data;
error = ppt_map_mmio(sc->vm, pptmmio->bus, pptmmio->slot,
pptmmio->func, pptmmio->gpa, pptmmio->len,
pptmmio->hpa);
break;
case VM_BIND_PPTDEV:
pptdev = (struct vm_pptdev *)data;
error = vm_assign_pptdev(sc->vm, pptdev->bus, pptdev->slot,
pptdev->func);
break;
case VM_UNBIND_PPTDEV:
pptdev = (struct vm_pptdev *)data;
error = vm_unassign_pptdev(sc->vm, pptdev->bus, pptdev->slot,
pptdev->func);
break;
case VM_INJECT_EXCEPTION:
vmexc = (struct vm_exception *)data;
error = vm_inject_exception(sc->vm, vmexc->cpuid, vmexc);
break;
case VM_INJECT_NMI:
vmnmi = (struct vm_nmi *)data;
error = vm_inject_nmi(sc->vm, vmnmi->cpuid);
break;
case VM_LAPIC_IRQ:
vmirq = (struct vm_lapic_irq *)data;
error = lapic_intr_edge(sc->vm, vmirq->cpuid, vmirq->vector);
break;
case VM_LAPIC_LOCAL_IRQ:
vmirq = (struct vm_lapic_irq *)data;
error = lapic_set_local_intr(sc->vm, vmirq->cpuid,
vmirq->vector);
break;
case VM_LAPIC_MSI:
vmmsi = (struct vm_lapic_msi *)data;
error = lapic_intr_msi(sc->vm, vmmsi->addr, vmmsi->msg);
break;
case VM_IOAPIC_ASSERT_IRQ:
ioapic_irq = (struct vm_ioapic_irq *)data;
error = vioapic_assert_irq(sc->vm, ioapic_irq->irq);
break;
case VM_IOAPIC_DEASSERT_IRQ:
ioapic_irq = (struct vm_ioapic_irq *)data;
error = vioapic_deassert_irq(sc->vm, ioapic_irq->irq);
break;
case VM_IOAPIC_PULSE_IRQ:
ioapic_irq = (struct vm_ioapic_irq *)data;
error = vioapic_pulse_irq(sc->vm, ioapic_irq->irq);
break;
case VM_IOAPIC_PINCOUNT:
*(int *)data = vioapic_pincount(sc->vm);
break;
case VM_ISA_ASSERT_IRQ:
isa_irq = (struct vm_isa_irq *)data;
error = vatpic_assert_irq(sc->vm, isa_irq->atpic_irq);
if (error == 0 && isa_irq->ioapic_irq != -1)
error = vioapic_assert_irq(sc->vm,
isa_irq->ioapic_irq);
break;
case VM_ISA_DEASSERT_IRQ:
isa_irq = (struct vm_isa_irq *)data;
error = vatpic_deassert_irq(sc->vm, isa_irq->atpic_irq);
if (error == 0 && isa_irq->ioapic_irq != -1)
error = vioapic_deassert_irq(sc->vm,
isa_irq->ioapic_irq);
break;
case VM_ISA_PULSE_IRQ:
isa_irq = (struct vm_isa_irq *)data;
error = vatpic_pulse_irq(sc->vm, isa_irq->atpic_irq);
if (error == 0 && isa_irq->ioapic_irq != -1)
error = vioapic_pulse_irq(sc->vm, isa_irq->ioapic_irq);
break;
case VM_ISA_SET_IRQ_TRIGGER:
isa_irq_trigger = (struct vm_isa_irq_trigger *)data;
error = vatpic_set_irq_trigger(sc->vm,
isa_irq_trigger->atpic_irq, isa_irq_trigger->trigger);
break;
case VM_MAP_MEMORY:
seg = (struct vm_memory_segment *)data;
error = vm_malloc(sc->vm, seg->gpa, seg->len);
break;
case VM_GET_MEMORY_SEG:
seg = (struct vm_memory_segment *)data;
seg->len = 0;
(void)vm_gpabase2memseg(sc->vm, seg->gpa, seg);
error = 0;
break;
case VM_GET_REGISTER:
vmreg = (struct vm_register *)data;
error = vm_get_register(sc->vm, vmreg->cpuid, vmreg->regnum,
&vmreg->regval);
break;
case VM_SET_REGISTER:
vmreg = (struct vm_register *)data;
error = vm_set_register(sc->vm, vmreg->cpuid, vmreg->regnum,
vmreg->regval);
break;
case VM_SET_SEGMENT_DESCRIPTOR:
vmsegdesc = (struct vm_seg_desc *)data;
error = vm_set_seg_desc(sc->vm, vmsegdesc->cpuid,
vmsegdesc->regnum,
&vmsegdesc->desc);
break;
case VM_GET_SEGMENT_DESCRIPTOR:
vmsegdesc = (struct vm_seg_desc *)data;
error = vm_get_seg_desc(sc->vm, vmsegdesc->cpuid,
vmsegdesc->regnum,
&vmsegdesc->desc);
break;
case VM_GET_CAPABILITY:
vmcap = (struct vm_capability *)data;
error = vm_get_capability(sc->vm, vmcap->cpuid,
vmcap->captype,
&vmcap->capval);
break;
case VM_SET_CAPABILITY:
vmcap = (struct vm_capability *)data;
error = vm_set_capability(sc->vm, vmcap->cpuid,
vmcap->captype,
vmcap->capval);
break;
case VM_SET_X2APIC_STATE:
x2apic = (struct vm_x2apic *)data;
error = vm_set_x2apic_state(sc->vm,
x2apic->cpuid, x2apic->state);
break;
case VM_GET_X2APIC_STATE:
x2apic = (struct vm_x2apic *)data;
error = vm_get_x2apic_state(sc->vm,
x2apic->cpuid, &x2apic->state);
break;
case VM_GET_GPA_PMAP:
gpapte = (struct vm_gpa_pte *)data;
pmap_get_mapping(vmspace_pmap(vm_get_vmspace(sc->vm)),
gpapte->gpa, gpapte->pte, &gpapte->ptenum);
error = 0;
break;
case VM_GET_HPET_CAPABILITIES:
error = vhpet_getcap((struct vm_hpet_cap *)data);
break;
case VM_GLA2GPA: {
CTASSERT(PROT_READ == VM_PROT_READ);
CTASSERT(PROT_WRITE == VM_PROT_WRITE);
CTASSERT(PROT_EXEC == VM_PROT_EXECUTE);
gg = (struct vm_gla2gpa *)data;
error = vmm_gla2gpa(sc->vm, gg->vcpuid, &gg->paging, gg->gla,
gg->prot, &gg->gpa);
KASSERT(error == 0 || error == 1 || error == -1,
("%s: vmm_gla2gpa unknown error %d", __func__, error));
if (error >= 0) {
/*
* error = 0: the translation was successful
* error = 1: a fault was injected into the guest
*/
gg->fault = error;
error = 0;
} else {
error = EFAULT;
}
break;
}
case VM_ACTIVATE_CPU:
vac = (struct vm_activate_cpu *)data;
error = vm_activate_cpu(sc->vm, vac->vcpuid);
break;
case VM_GET_CPUS:
error = 0;
vm_cpuset = (struct vm_cpuset *)data;
size = vm_cpuset->cpusetsize;
if (size < sizeof(cpuset_t) || size > CPU_MAXSIZE / NBBY) {
error = ERANGE;
break;
}
cpuset = malloc(size, M_TEMP, M_WAITOK | M_ZERO);
if (vm_cpuset->which == VM_ACTIVE_CPUS)
*cpuset = vm_active_cpus(sc->vm);
else if (vm_cpuset->which == VM_SUSPENDED_CPUS)
*cpuset = vm_suspended_cpus(sc->vm);
else
error = EINVAL;
if (error == 0)
error = copyout(cpuset, vm_cpuset->cpus, size);
free(cpuset, M_TEMP);
break;
case VM_SET_INTINFO:
vmii = (struct vm_intinfo *)data;
error = vm_exit_intinfo(sc->vm, vmii->vcpuid, vmii->info1);
break;
case VM_GET_INTINFO:
vmii = (struct vm_intinfo *)data;
error = vm_get_intinfo(sc->vm, vmii->vcpuid, &vmii->info1,
&vmii->info2);
break;
default:
error = ENOTTY;
break;
}
if (state_changed == 1) {
vcpu_set_state(sc->vm, vcpu, VCPU_IDLE, false);
} else if (state_changed == 2) {
for (vcpu = 0; vcpu < VM_MAXCPU; vcpu++)
vcpu_set_state(sc->vm, vcpu, VCPU_IDLE, false);
}
done:
/* Make sure that no handler returns a bogus value like ERESTART */
KASSERT(error >= 0, ("vmmdev_ioctl: invalid error return %d", error));
return (error);
}
static int
vmmdev_mmap_single(struct cdev *cdev, vm_ooffset_t *offset,
vm_size_t size, struct vm_object **object, int nprot)
{
int error;
struct vmmdev_softc *sc;
sc = vmmdev_lookup2(cdev);
if (sc != NULL && (nprot & PROT_EXEC) == 0)
error = vm_get_memobj(sc->vm, *offset, size, offset, object);
else
error = EINVAL;
return (error);
}
static void
vmmdev_destroy(void *arg)
{
struct vmmdev_softc *sc = arg;
if (sc->cdev != NULL)
destroy_dev(sc->cdev);
if (sc->vm != NULL)
vm_destroy(sc->vm);
if ((sc->flags & VSC_LINKED) != 0) {
mtx_lock(&vmmdev_mtx);
SLIST_REMOVE(&head, sc, vmmdev_softc, link);
mtx_unlock(&vmmdev_mtx);
}
free(sc, M_VMMDEV);
}
static int
sysctl_vmm_destroy(SYSCTL_HANDLER_ARGS)
{
int error;
char buf[VM_MAX_NAMELEN];
struct vmmdev_softc *sc;
struct cdev *cdev;
strlcpy(buf, "beavis", sizeof(buf));
error = sysctl_handle_string(oidp, buf, sizeof(buf), req);
if (error != 0 || req->newptr == NULL)
return (error);
mtx_lock(&vmmdev_mtx);
sc = vmmdev_lookup(buf);
if (sc == NULL || sc->cdev == NULL) {
mtx_unlock(&vmmdev_mtx);
return (EINVAL);
}
/*
* The 'cdev' will be destroyed asynchronously when 'si_threadcount'
* goes down to 0 so we should not do it again in the callback.
*/
cdev = sc->cdev;
sc->cdev = NULL;
mtx_unlock(&vmmdev_mtx);
/*
* Schedule the 'cdev' to be destroyed:
*
* - any new operations on this 'cdev' will return an error (ENXIO).
*
* - when the 'si_threadcount' dwindles down to zero the 'cdev' will
* be destroyed and the callback will be invoked in a taskqueue
* context.
*/
destroy_dev_sched_cb(cdev, vmmdev_destroy, sc);
return (0);
}
SYSCTL_PROC(_hw_vmm, OID_AUTO, destroy, CTLTYPE_STRING | CTLFLAG_RW,
NULL, 0, sysctl_vmm_destroy, "A", NULL);
static struct cdevsw vmmdevsw = {
.d_name = "vmmdev",
.d_version = D_VERSION,
.d_ioctl = vmmdev_ioctl,
.d_mmap_single = vmmdev_mmap_single,
.d_read = vmmdev_rw,
.d_write = vmmdev_rw,
};
static int
sysctl_vmm_create(SYSCTL_HANDLER_ARGS)
{
int error;
struct vm *vm;
struct cdev *cdev;
struct vmmdev_softc *sc, *sc2;
char buf[VM_MAX_NAMELEN];
strlcpy(buf, "beavis", sizeof(buf));
error = sysctl_handle_string(oidp, buf, sizeof(buf), req);
if (error != 0 || req->newptr == NULL)
return (error);
mtx_lock(&vmmdev_mtx);
sc = vmmdev_lookup(buf);
mtx_unlock(&vmmdev_mtx);
if (sc != NULL)
return (EEXIST);
error = vm_create(buf, &vm);
if (error != 0)
return (error);
sc = malloc(sizeof(struct vmmdev_softc), M_VMMDEV, M_WAITOK | M_ZERO);
sc->vm = vm;
/*
* Lookup the name again just in case somebody sneaked in when we
* dropped the lock.
*/
mtx_lock(&vmmdev_mtx);
sc2 = vmmdev_lookup(buf);
if (sc2 == NULL) {
SLIST_INSERT_HEAD(&head, sc, link);
sc->flags |= VSC_LINKED;
}
mtx_unlock(&vmmdev_mtx);
if (sc2 != NULL) {
vmmdev_destroy(sc);
return (EEXIST);
}
error = make_dev_p(MAKEDEV_CHECKNAME, &cdev, &vmmdevsw, NULL,
UID_ROOT, GID_WHEEL, 0600, "vmm/%s", buf);
if (error != 0) {
vmmdev_destroy(sc);
return (error);
}
mtx_lock(&vmmdev_mtx);
sc->cdev = cdev;
sc->cdev->si_drv1 = sc;
mtx_unlock(&vmmdev_mtx);
return (0);
}
SYSCTL_PROC(_hw_vmm, OID_AUTO, create, CTLTYPE_STRING | CTLFLAG_RW,
NULL, 0, sysctl_vmm_create, "A", NULL);
void
vmmdev_init(void)
{
mtx_init(&vmmdev_mtx, "vmm device mutex", NULL, MTX_DEF);
}
int
vmmdev_cleanup(void)
{
int error;
if (SLIST_EMPTY(&head))
error = 0;
else
error = EBUSY;
return (error);
}