freebsd-dev/sys/amd64/vmm/io/ppt.c
Peter Grehan cd942e0f25 MSI-x interrupt support for PCI pass-thru devices.
Includes instruction emulation for memory r/w access. This
opens the door for io-apic, local apic, hpet timer, and
legacy device emulation.

Submitted by:	ryan dot berryhill at sandvine dot com
Reviewed by:	grehan
Obtained from:	Sandvine
2012-04-28 16:28:00 +00:00

624 lines
14 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/kernel.h>
#include <sys/malloc.h>
#include <sys/module.h>
#include <sys/bus.h>
#include <sys/pciio.h>
#include <sys/rman.h>
#include <sys/smp.h>
#include <dev/pci/pcivar.h>
#include <dev/pci/pcireg.h>
#include <machine/resource.h>
#include <machine/vmm.h>
#include <machine/vmm_dev.h>
#include "vmm_lapic.h"
#include "vmm_ktr.h"
#include "iommu.h"
#include "ppt.h"
#define MAX_PPTDEVS (sizeof(pptdevs) / sizeof(pptdevs[0]))
#define MAX_MMIOSEGS (PCIR_MAX_BAR_0 + 1)
#define MAX_MSIMSGS 32
MALLOC_DEFINE(M_PPTMSIX, "pptmsix", "Passthru MSI-X resources");
struct pptintr_arg { /* pptintr(pptintr_arg) */
struct pptdev *pptdev;
int vec;
int vcpu;
};
static struct pptdev {
device_t dev;
struct vm *vm; /* owner of this device */
struct vm_memory_segment mmio[MAX_MMIOSEGS];
struct {
int num_msgs; /* guest state */
int vector;
int vcpu;
int startrid; /* host state */
struct resource *res[MAX_MSIMSGS];
void *cookie[MAX_MSIMSGS];
struct pptintr_arg arg[MAX_MSIMSGS];
} msi;
struct {
int num_msgs;
int startrid;
int msix_table_rid;
struct resource *msix_table_res;
struct resource **res;
void **cookie;
struct pptintr_arg *arg;
} msix;
} pptdevs[32];
static int num_pptdevs;
static int
ppt_probe(device_t dev)
{
int bus, slot, func;
struct pci_devinfo *dinfo;
dinfo = (struct pci_devinfo *)device_get_ivars(dev);
bus = pci_get_bus(dev);
slot = pci_get_slot(dev);
func = pci_get_function(dev);
/*
* To qualify as a pci passthrough device a device must:
* - be allowed by administrator to be used in this role
* - be an endpoint device
*/
if (vmm_is_pptdev(bus, slot, func) &&
(dinfo->cfg.hdrtype & PCIM_HDRTYPE) == PCIM_HDRTYPE_NORMAL)
return (0);
else
return (ENXIO);
}
static int
ppt_attach(device_t dev)
{
int n;
if (num_pptdevs >= MAX_PPTDEVS) {
printf("ppt_attach: maximum number of pci passthrough devices "
"exceeded\n");
return (ENXIO);
}
n = num_pptdevs++;
pptdevs[n].dev = dev;
if (bootverbose)
device_printf(dev, "attached\n");
return (0);
}
static int
ppt_detach(device_t dev)
{
/*
* XXX check whether there are any pci passthrough devices assigned
* to guests before we allow this driver to detach.
*/
return (0);
}
static device_method_t ppt_methods[] = {
/* Device interface */
DEVMETHOD(device_probe, ppt_probe),
DEVMETHOD(device_attach, ppt_attach),
DEVMETHOD(device_detach, ppt_detach),
{0, 0}
};
static devclass_t ppt_devclass;
DEFINE_CLASS_0(ppt, ppt_driver, ppt_methods, 0);
DRIVER_MODULE(ppt, pci, ppt_driver, ppt_devclass, NULL, NULL);
static struct pptdev *
ppt_find(int bus, int slot, int func)
{
device_t dev;
int i, b, s, f;
for (i = 0; i < num_pptdevs; i++) {
dev = pptdevs[i].dev;
b = pci_get_bus(dev);
s = pci_get_slot(dev);
f = pci_get_function(dev);
if (bus == b && slot == s && func == f)
return (&pptdevs[i]);
}
return (NULL);
}
static void
ppt_unmap_mmio(struct vm *vm, struct pptdev *ppt)
{
int i;
struct vm_memory_segment *seg;
for (i = 0; i < MAX_MMIOSEGS; i++) {
seg = &ppt->mmio[i];
if (seg->len == 0)
continue;
(void)vm_unmap_mmio(vm, seg->gpa, seg->len);
bzero(seg, sizeof(struct vm_memory_segment));
}
}
static void
ppt_teardown_msi(struct pptdev *ppt)
{
int i, rid;
void *cookie;
struct resource *res;
if (ppt->msi.num_msgs == 0)
return;
for (i = 0; i < ppt->msi.num_msgs; i++) {
rid = ppt->msi.startrid + i;
res = ppt->msi.res[i];
cookie = ppt->msi.cookie[i];
if (cookie != NULL)
bus_teardown_intr(ppt->dev, res, cookie);
if (res != NULL)
bus_release_resource(ppt->dev, SYS_RES_IRQ, rid, res);
ppt->msi.res[i] = NULL;
ppt->msi.cookie[i] = NULL;
}
if (ppt->msi.startrid == 1)
pci_release_msi(ppt->dev);
ppt->msi.num_msgs = 0;
}
static void
ppt_teardown_msix_intr(struct pptdev *ppt, int idx)
{
int rid;
struct resource *res;
void *cookie;
rid = ppt->msix.startrid + idx;
res = ppt->msix.res[idx];
cookie = ppt->msix.cookie[idx];
if (cookie != NULL)
bus_teardown_intr(ppt->dev, res, cookie);
if (res != NULL)
bus_release_resource(ppt->dev, SYS_RES_IRQ, rid, res);
ppt->msix.res[idx] = NULL;
ppt->msix.cookie[idx] = NULL;
}
static void
ppt_teardown_msix(struct pptdev *ppt)
{
int i, error;
if (ppt->msix.num_msgs == 0)
return;
for (i = 0; i < ppt->msix.num_msgs; i++)
ppt_teardown_msix_intr(ppt, i);
if (ppt->msix.msix_table_res) {
bus_release_resource(ppt->dev, SYS_RES_MEMORY,
ppt->msix.msix_table_rid,
ppt->msix.msix_table_res);
ppt->msix.msix_table_res = NULL;
ppt->msix.msix_table_rid = 0;
}
free(ppt->msix.res, M_PPTMSIX);
free(ppt->msix.cookie, M_PPTMSIX);
free(ppt->msix.arg, M_PPTMSIX);
error = pci_release_msi(ppt->dev);
if (error)
printf("ppt_teardown_msix: Failed to release MSI-X resources (error %i)\n", error);
ppt->msix.num_msgs = 0;
}
int
ppt_assign_device(struct vm *vm, int bus, int slot, int func)
{
struct pptdev *ppt;
ppt = ppt_find(bus, slot, func);
if (ppt != NULL) {
/*
* If this device is owned by a different VM then we
* cannot change its owner.
*/
if (ppt->vm != NULL && ppt->vm != vm)
return (EBUSY);
ppt->vm = vm;
iommu_add_device(vm_iommu_domain(vm), bus, slot, func);
return (0);
}
return (ENOENT);
}
int
ppt_unassign_device(struct vm *vm, int bus, int slot, int func)
{
struct pptdev *ppt;
ppt = ppt_find(bus, slot, func);
if (ppt != NULL) {
/*
* If this device is not owned by this 'vm' then bail out.
*/
if (ppt->vm != vm)
return (EBUSY);
ppt_unmap_mmio(vm, ppt);
ppt_teardown_msi(ppt);
ppt_teardown_msix(ppt);
iommu_remove_device(vm_iommu_domain(vm), bus, slot, func);
ppt->vm = NULL;
return (0);
}
return (ENOENT);
}
int
ppt_unassign_all(struct vm *vm)
{
int i, bus, slot, func;
device_t dev;
for (i = 0; i < num_pptdevs; i++) {
if (pptdevs[i].vm == vm) {
dev = pptdevs[i].dev;
bus = pci_get_bus(dev);
slot = pci_get_slot(dev);
func = pci_get_function(dev);
ppt_unassign_device(vm, bus, slot, func);
}
}
return (0);
}
int
ppt_map_mmio(struct vm *vm, int bus, int slot, int func,
vm_paddr_t gpa, size_t len, vm_paddr_t hpa)
{
int i, error;
struct vm_memory_segment *seg;
struct pptdev *ppt;
ppt = ppt_find(bus, slot, func);
if (ppt != NULL) {
if (ppt->vm != vm)
return (EBUSY);
for (i = 0; i < MAX_MMIOSEGS; i++) {
seg = &ppt->mmio[i];
if (seg->len == 0) {
error = vm_map_mmio(vm, gpa, len, hpa);
if (error == 0) {
seg->gpa = gpa;
seg->len = len;
seg->hpa = hpa;
}
return (error);
}
}
return (ENOSPC);
}
return (ENOENT);
}
static int
pptintr(void *arg)
{
int vec;
struct pptdev *ppt;
struct pptintr_arg *pptarg;
pptarg = arg;
ppt = pptarg->pptdev;
vec = pptarg->vec;
if (ppt->vm != NULL)
(void) lapic_set_intr(ppt->vm, pptarg->vcpu, vec);
else {
/*
* XXX
* This is not expected to happen - panic?
*/
}
/*
* For legacy interrupts give other filters a chance in case
* the interrupt was not generated by the passthrough device.
*/
if (ppt->msi.startrid == 0)
return (FILTER_STRAY);
else
return (FILTER_HANDLED);
}
/*
* XXX
* When we try to free the MSI resource the kernel will bind the thread to
* the host cpu was originally handling the MSI. The function freeing the
* MSI vector (apic_free_vector()) will panic the kernel if the thread
* is already bound to a cpu.
*
* So, we temporarily unbind the vcpu thread before freeing the MSI resource.
*/
static void
PPT_TEARDOWN_MSI(struct vm *vm, int vcpu, struct pptdev *ppt)
{
int pincpu = -1;
vm_get_pinning(vm, vcpu, &pincpu);
if (pincpu >= 0)
vm_set_pinning(vm, vcpu, -1);
ppt_teardown_msi(ppt);
if (pincpu >= 0)
vm_set_pinning(vm, vcpu, pincpu);
}
int
ppt_setup_msi(struct vm *vm, int vcpu, int bus, int slot, int func,
int destcpu, int vector, int numvec)
{
int i, rid, flags;
int msi_count, startrid, error, tmp;
struct pptdev *ppt;
if ((destcpu >= VM_MAXCPU || destcpu < 0) ||
(vector < 0 || vector > 255) ||
(numvec < 0 || numvec > MAX_MSIMSGS))
return (EINVAL);
ppt = ppt_find(bus, slot, func);
if (ppt == NULL)
return (ENOENT);
if (ppt->vm != vm) /* Make sure we own this device */
return (EBUSY);
/* Free any allocated resources */
PPT_TEARDOWN_MSI(vm, vcpu, ppt);
if (numvec == 0) /* nothing more to do */
return (0);
flags = RF_ACTIVE;
msi_count = pci_msi_count(ppt->dev);
if (msi_count == 0) {
startrid = 0; /* legacy interrupt */
msi_count = 1;
flags |= RF_SHAREABLE;
} else
startrid = 1; /* MSI */
/*
* The device must be capable of supporting the number of vectors
* the guest wants to allocate.
*/
if (numvec > msi_count)
return (EINVAL);
/*
* Make sure that we can allocate all the MSI vectors that are needed
* by the guest.
*/
if (startrid == 1) {
tmp = numvec;
error = pci_alloc_msi(ppt->dev, &tmp);
if (error)
return (error);
else if (tmp != numvec) {
pci_release_msi(ppt->dev);
return (ENOSPC);
} else {
/* success */
}
}
ppt->msi.vector = vector;
ppt->msi.vcpu = destcpu;
ppt->msi.startrid = startrid;
/*
* Allocate the irq resource and attach it to the interrupt handler.
*/
for (i = 0; i < numvec; i++) {
ppt->msi.num_msgs = i + 1;
ppt->msi.cookie[i] = NULL;
rid = startrid + i;
ppt->msi.res[i] = bus_alloc_resource_any(ppt->dev, SYS_RES_IRQ,
&rid, flags);
if (ppt->msi.res[i] == NULL)
break;
ppt->msi.arg[i].pptdev = ppt;
ppt->msi.arg[i].vec = vector + i;
error = bus_setup_intr(ppt->dev, ppt->msi.res[i],
INTR_TYPE_NET | INTR_MPSAFE,
pptintr, NULL, &ppt->msi.arg[i],
&ppt->msi.cookie[i]);
if (error != 0)
break;
}
if (i < numvec) {
PPT_TEARDOWN_MSI(vm, vcpu, ppt);
return (ENXIO);
}
return (0);
}
int
ppt_setup_msix(struct vm *vm, int vcpu, int bus, int slot, int func,
int idx, uint32_t msg, uint32_t vector_control, uint64_t addr)
{
struct pptdev *ppt;
struct pci_devinfo *dinfo;
int numvec, vector_count, rid, error;
size_t res_size, cookie_size, arg_size;
ppt = ppt_find(bus, slot, func);
if (ppt == NULL)
return (ENOENT);
if (ppt->vm != vm) /* Make sure we own this device */
return (EBUSY);
dinfo = device_get_ivars(ppt->dev);
if (!dinfo)
return (ENXIO);
/*
* First-time configuration:
* Allocate the MSI-X table
* Allocate the IRQ resources
* Set up some variables in ppt->msix
*/
if (!ppt->msix.msix_table_res) {
ppt->msix.res = NULL;
ppt->msix.cookie = NULL;
ppt->msix.arg = NULL;
rid = dinfo->cfg.msix.msix_table_bar;
ppt->msix.msix_table_res = bus_alloc_resource_any(ppt->dev, SYS_RES_MEMORY,
&rid, RF_ACTIVE);
if (ppt->msix.msix_table_res == NULL)
return (ENOSPC);
ppt->msix.msix_table_rid = rid;
vector_count = numvec = pci_msix_count(ppt->dev);
error = pci_alloc_msix(ppt->dev, &numvec);
if (error)
return (error);
else if (vector_count != numvec) {
pci_release_msi(ppt->dev);
return (ENOSPC);
}
ppt->msix.num_msgs = numvec;
ppt->msix.startrid = 1;
res_size = numvec * sizeof(ppt->msix.res[0]);
cookie_size = numvec * sizeof(ppt->msix.cookie[0]);
arg_size = numvec * sizeof(ppt->msix.arg[0]);
ppt->msix.res = malloc(res_size, M_PPTMSIX, M_WAITOK);
ppt->msix.cookie = malloc(cookie_size, M_PPTMSIX, M_WAITOK);
ppt->msix.arg = malloc(arg_size, M_PPTMSIX, M_WAITOK);
if (ppt->msix.res == NULL || ppt->msix.cookie == NULL ||
ppt->msix.arg == NULL) {
ppt_teardown_msix(ppt);
return (ENOSPC);
}
bzero(ppt->msix.res, res_size);
bzero(ppt->msix.cookie, cookie_size);
bzero(ppt->msix.arg, arg_size);
}
if ((vector_control & PCIM_MSIX_VCTRL_MASK) == 0) {
/* Tear down the IRQ if it's already set up */
ppt_teardown_msix_intr(ppt, idx);
/* Allocate the IRQ resource */
ppt->msix.cookie[idx] = NULL;
rid = ppt->msix.startrid + idx;
ppt->msix.res[idx] = bus_alloc_resource_any(ppt->dev, SYS_RES_IRQ,
&rid, RF_ACTIVE);
if (ppt->msix.res[idx] == NULL)
return (ENXIO);
ppt->msix.arg[idx].pptdev = ppt;
ppt->msix.arg[idx].vec = msg;
ppt->msix.arg[idx].vcpu = (addr >> 12) & 0xFF;
/* Setup the MSI-X interrupt */
error = bus_setup_intr(ppt->dev, ppt->msix.res[idx],
INTR_TYPE_NET | INTR_MPSAFE,
pptintr, NULL, &ppt->msix.arg[idx],
&ppt->msix.cookie[idx]);
if (error != 0) {
bus_teardown_intr(ppt->dev, ppt->msix.res[idx], ppt->msix.cookie[idx]);
bus_release_resource(ppt->dev, SYS_RES_IRQ, rid, ppt->msix.res[idx]);
ppt->msix.cookie[idx] = NULL;
ppt->msix.res[idx] = NULL;
return (ENXIO);
}
} else {
/* Masked, tear it down if it's already been set up */
ppt_teardown_msix_intr(ppt, idx);
}
return (0);
}