freebsd-nq/usr.sbin/bhyve/pci_virtio_input.c
Corvin Köhne 054accac71 Add a virtio-input device emulation.
This will be used to inject keyboard/mouse input events into a guest.
The command line syntax is:
   -s <slot>,virtio-input,/dev/input/eventX

Reviewed by:	jhb (bhyve), grehan
Obtained from:	Corvin Köhne <C.Koehne@beckhoff.com>
MFC after:	3 weeks
Relnotes:	yes
Differential Revision:	https://reviews.freebsd.org/D30020
2021-06-08 19:05:09 +10:00

783 lines
19 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 2021 Beckhoff Automation GmbH & Co. KG
* 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
* in this position and unchanged.
* 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.
*/
/*
* virtio input device emulation.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#ifndef WITHOUT_CAPSICUM
#include <sys/capsicum.h>
#include <capsicum_helpers.h>
#endif
#include <sys/ioctl.h>
#include <sys/linker_set.h>
#include <sys/uio.h>
#include <dev/evdev/input.h>
#include <assert.h>
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <pthread.h>
#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sysexits.h>
#include <unistd.h>
#include "bhyverun.h"
#include "config.h"
#include "debug.h"
#include "mevent.h"
#include "pci_emul.h"
#include "virtio.h"
#define VTINPUT_RINGSZ 64
#define VTINPUT_MAX_PKT_LEN 10
/*
* Queue definitions.
*/
#define VTINPUT_EVENTQ 0
#define VTINPUT_STATUSQ 1
#define VTINPUT_MAXQ 2
static int pci_vtinput_debug;
#define DPRINTF(params) \
if (pci_vtinput_debug) \
PRINTLN params
#define WPRINTF(params) PRINTLN params
enum vtinput_config_select {
VTINPUT_CFG_UNSET = 0x00,
VTINPUT_CFG_ID_NAME = 0x01,
VTINPUT_CFG_ID_SERIAL = 0x02,
VTINPUT_CFG_ID_DEVIDS = 0x03,
VTINPUT_CFG_PROP_BITS = 0x10,
VTINPUT_CFG_EV_BITS = 0x11,
VTINPUT_CFG_ABS_INFO = 0x12
};
struct vtinput_absinfo {
uint32_t min;
uint32_t max;
uint32_t fuzz;
uint32_t flat;
uint32_t res;
} __packed;
struct vtinput_devids {
uint16_t bustype;
uint16_t vendor;
uint16_t product;
uint16_t version;
} __packed;
struct vtinput_config {
uint8_t select;
uint8_t subsel;
uint8_t size;
uint8_t reserved[5];
union {
char string[128];
uint8_t bitmap[128];
struct vtinput_absinfo abs;
struct vtinput_devids ids;
} u;
} __packed;
struct vtinput_event {
uint16_t type;
uint16_t code;
uint32_t value;
} __packed;
struct vtinput_event_elem {
struct vtinput_event event;
struct iovec iov;
uint16_t idx;
};
struct vtinput_eventqueue {
struct vtinput_event_elem *events;
uint32_t size;
uint32_t idx;
};
/*
* Per-device softc
*/
struct pci_vtinput_softc {
struct virtio_softc vsc_vs;
struct vqueue_info vsc_queues[VTINPUT_MAXQ];
pthread_mutex_t vsc_mtx;
const char *vsc_evdev;
int vsc_fd;
struct vtinput_config vsc_config;
int vsc_config_valid;
struct mevent *vsc_evp;
struct vtinput_eventqueue vsc_eventqueue;
};
static void pci_vtinput_reset(void *);
static int pci_vtinput_cfgread(void *, int, int, uint32_t *);
static int pci_vtinput_cfgwrite(void *, int, int, uint32_t);
static struct virtio_consts vtinput_vi_consts = {
"vtinput", /* our name */
VTINPUT_MAXQ, /* we support 1 virtqueue */
sizeof(struct vtinput_config), /* config reg size */
pci_vtinput_reset, /* reset */
NULL, /* device-wide qnotify -- not used */
pci_vtinput_cfgread, /* read virtio config */
pci_vtinput_cfgwrite, /* write virtio config */
NULL, /* apply negotiated features */
0, /* our capabilities */
};
static void
pci_vtinput_reset(void *vsc)
{
struct pci_vtinput_softc *sc = vsc;
DPRINTF(("%s: device reset requested", __func__));
vi_reset_dev(&sc->vsc_vs);
}
static void
pci_vtinput_notify_eventq(void *vsc, struct vqueue_info *vq)
{
DPRINTF(("%s", __func__));
}
static void
pci_vtinput_notify_statusq(void *vsc, struct vqueue_info *vq)
{
struct pci_vtinput_softc *sc = vsc;
while (vq_has_descs(vq)) {
/* get descriptor chain */
struct iovec iov;
struct vi_req req;
const int n = vq_getchain(vq, &iov, 1, &req);
if (n <= 0) {
WPRINTF(("%s: invalid descriptor: %d", __func__, n));
return;
}
/* get event */
struct vtinput_event event;
memcpy(&event, iov.iov_base, sizeof(event));
/*
* on multi touch devices:
* - host send EV_MSC to guest
* - guest sends EV_MSC back to host
* - host writes EV_MSC to evdev
* - evdev saves EV_MSC in it's event buffer
* - host receives an extra EV_MSC by reading the evdev event
* buffer
* - frames become larger and larger
* avoid endless loops by ignoring EV_MSC
*/
if (event.type == EV_MSC) {
vq_relchain(vq, req.idx, sizeof(event));
continue;
}
/* send event to evdev */
struct input_event host_event;
host_event.type = event.type;
host_event.code = event.code;
host_event.value = event.value;
if (gettimeofday(&host_event.time, NULL) != 0) {
WPRINTF(("%s: failed gettimeofday", __func__));
}
if (write(sc->vsc_fd, &host_event, sizeof(host_event)) == -1) {
WPRINTF(("%s: failed to write host_event", __func__));
}
vq_relchain(vq, req.idx, sizeof(event));
}
vq_endchains(vq, 1);
}
static int
pci_vtinput_get_bitmap(struct pci_vtinput_softc *sc, int cmd, int count)
{
if (count <= 0 || !sc) {
return (-1);
}
/* query bitmap */
memset(sc->vsc_config.u.bitmap, 0, sizeof(sc->vsc_config.u.bitmap));
if (ioctl(sc->vsc_fd, cmd, sc->vsc_config.u.bitmap) < 0) {
return (-1);
}
/* get number of set bytes in bitmap */
for (int i = count - 1; i >= 0; i--) {
if (sc->vsc_config.u.bitmap[i]) {
return i + 1;
}
}
return (-1);
}
static int
pci_vtinput_read_config_id_name(struct pci_vtinput_softc *sc)
{
char name[128];
if (ioctl(sc->vsc_fd, EVIOCGNAME(sizeof(name) - 1), name) < 0) {
return (1);
}
memcpy(sc->vsc_config.u.string, name, sizeof(name));
sc->vsc_config.size = strnlen(name, sizeof(name));
return (0);
}
static int
pci_vtinput_read_config_id_serial(struct pci_vtinput_softc *sc)
{
/* serial isn't supported */
sc->vsc_config.size = 0;
return (0);
}
static int
pci_vtinput_read_config_id_devids(struct pci_vtinput_softc *sc)
{
struct input_id devids;
if (ioctl(sc->vsc_fd, EVIOCGID, &devids)) {
return (1);
}
sc->vsc_config.u.ids.bustype = devids.bustype;
sc->vsc_config.u.ids.vendor = devids.vendor;
sc->vsc_config.u.ids.product = devids.product;
sc->vsc_config.u.ids.version = devids.version;
sc->vsc_config.size = sizeof(struct vtinput_devids);
return (0);
}
static int
pci_vtinput_read_config_prop_bits(struct pci_vtinput_softc *sc)
{
/*
* Evdev bitmap countains 1 bit per count. Additionally evdev bitmaps
* are arrays of longs instead of chars. Calculate how many longs are
* required for evdev bitmap. Multiply that with sizeof(long) to get the
* number of elements.
*/
const int count = howmany(INPUT_PROP_CNT, sizeof(long) * 8) *
sizeof(long);
const unsigned int cmd = EVIOCGPROP(count);
const int size = pci_vtinput_get_bitmap(sc, cmd, count);
if (size <= 0) {
return (1);
}
sc->vsc_config.size = size;
return (0);
}
static int
pci_vtinput_read_config_ev_bits(struct pci_vtinput_softc *sc, uint8_t type)
{
int count;
switch (type) {
case EV_KEY:
count = KEY_CNT;
break;
case EV_REL:
count = REL_CNT;
break;
case EV_ABS:
count = ABS_CNT;
break;
case EV_MSC:
count = MSC_CNT;
break;
case EV_SW:
count = SW_CNT;
break;
case EV_LED:
count = LED_CNT;
break;
default:
return (1);
}
/*
* Evdev bitmap countains 1 bit per count. Additionally evdev bitmaps
* are arrays of longs instead of chars. Calculate how many longs are
* required for evdev bitmap. Multiply that with sizeof(long) to get the
* number of elements.
*/
count = howmany(count, sizeof(long) * 8) * sizeof(long);
const unsigned int cmd = EVIOCGBIT(sc->vsc_config.subsel, count);
const int size = pci_vtinput_get_bitmap(sc, cmd, count);
if (size <= 0) {
return (1);
}
sc->vsc_config.size = size;
return (0);
}
static int
pci_vtinput_read_config_abs_info(struct pci_vtinput_softc *sc)
{
/* check if evdev has EV_ABS */
if (!pci_vtinput_read_config_ev_bits(sc, EV_ABS)) {
return (1);
}
/* get abs information */
struct input_absinfo abs;
if (ioctl(sc->vsc_fd, EVIOCGABS(sc->vsc_config.subsel), &abs) < 0) {
return (1);
}
/* save abs information */
sc->vsc_config.u.abs.min = abs.minimum;
sc->vsc_config.u.abs.max = abs.maximum;
sc->vsc_config.u.abs.fuzz = abs.fuzz;
sc->vsc_config.u.abs.flat = abs.flat;
sc->vsc_config.u.abs.res = abs.resolution;
sc->vsc_config.size = sizeof(struct vtinput_absinfo);
return (0);
}
static int
pci_vtinput_read_config(struct pci_vtinput_softc *sc)
{
switch (sc->vsc_config.select) {
case VTINPUT_CFG_UNSET:
return (0);
case VTINPUT_CFG_ID_NAME:
return pci_vtinput_read_config_id_name(sc);
case VTINPUT_CFG_ID_SERIAL:
return pci_vtinput_read_config_id_serial(sc);
case VTINPUT_CFG_ID_DEVIDS:
return pci_vtinput_read_config_id_devids(sc);
case VTINPUT_CFG_PROP_BITS:
return pci_vtinput_read_config_prop_bits(sc);
case VTINPUT_CFG_EV_BITS:
return pci_vtinput_read_config_ev_bits(
sc, sc->vsc_config.subsel);
case VTINPUT_CFG_ABS_INFO:
return pci_vtinput_read_config_abs_info(sc);
default:
return (1);
}
}
static int
pci_vtinput_cfgread(void *vsc, int offset, int size, uint32_t *retval)
{
struct pci_vtinput_softc *sc = vsc;
/* check for valid offset and size */
if (offset + size > sizeof(struct vtinput_config)) {
WPRINTF(("%s: read to invalid offset/size %d/%d", __func__,
offset, size));
memset(retval, 0, size);
return (0);
}
/* read new config values, if select and subsel changed. */
if (!sc->vsc_config_valid) {
if (pci_vtinput_read_config(sc) != 0) {
DPRINTF(("%s: could not read config %d/%d", __func__,
sc->vsc_config.select, sc->vsc_config.subsel));
memset(retval, 0, size);
return (0);
}
sc->vsc_config_valid = 1;
}
uint8_t *ptr = (uint8_t *)&sc->vsc_config;
memcpy(retval, ptr + offset, size);
return (0);
}
static int
pci_vtinput_cfgwrite(void *vsc, int offset, int size, uint32_t value)
{
struct pci_vtinput_softc *sc = vsc;
/* guest can only write to select and subsel fields */
if (offset + size > 2) {
WPRINTF(("%s: write to readonly reg %d", __func__, offset));
return (1);
}
/* copy value into config */
uint8_t *ptr = (uint8_t *)&sc->vsc_config;
memcpy(ptr + offset, &value, size);
/* select/subsel changed, query new config on next cfgread */
sc->vsc_config_valid = 0;
return (0);
}
static int
vtinput_eventqueue_add_event(
struct vtinput_eventqueue *queue, struct input_event *e)
{
/* check if queue is full */
if (queue->idx >= queue->size) {
/* alloc new elements for queue */
const uint32_t newSize = queue->idx;
const void *newPtr = realloc(queue->events,
queue->size * sizeof(struct vtinput_event_elem));
if (newPtr == NULL) {
WPRINTF(("%s: realloc memory for eventqueue failed!",
__func__));
return (1);
}
/* save new size and eventqueue */
queue->events = (struct vtinput_event_elem *)newPtr;
queue->size = newSize;
}
/* save event */
struct vtinput_event *event = &queue->events[queue->idx].event;
event->type = e->type;
event->code = e->code;
event->value = e->value;
queue->idx++;
return (0);
}
static void
vtinput_eventqueue_clear(struct vtinput_eventqueue *queue)
{
/* just reset index to clear queue */
queue->idx = 0;
}
static void
vtinput_eventqueue_send_events(
struct vtinput_eventqueue *queue, struct vqueue_info *vq)
{
/*
* First iteration through eventqueue:
* Get descriptor chains.
*/
for (uint32_t i = 0; i < queue->idx; ++i) {
/* get descriptor */
if (!vq_has_descs(vq)) {
/*
* We don't have enough descriptors for all events.
* Return chains back to guest.
*/
vq_retchains(vq, i);
WPRINTF((
"%s: not enough available descriptors, dropping %d events",
__func__, queue->idx));
goto done;
}
/* get descriptor chain */
struct iovec iov;
struct vi_req req;
const int n = vq_getchain(vq, &iov, 1, &req);
if (n <= 0) {
WPRINTF(("%s: invalid descriptor: %d", __func__, n));
return;
}
if (n != 1) {
WPRINTF(
("%s: invalid number of descriptors in chain: %d",
__func__, n));
/* release invalid chain */
vq_relchain(vq, req.idx, 0);
return;
}
if (iov.iov_len < sizeof(struct vtinput_event)) {
WPRINTF(("%s: invalid descriptor length: %lu", __func__,
iov.iov_len));
/* release invalid chain */
vq_relchain(vq, req.idx, 0);
return;
}
/* save descriptor */
queue->events[i].iov = iov;
queue->events[i].idx = req.idx;
}
/*
* Second iteration through eventqueue:
* Send events to guest by releasing chains
*/
for (uint32_t i = 0; i < queue->idx; ++i) {
struct vtinput_event_elem event = queue->events[i];
memcpy(event.iov.iov_base, &event.event,
sizeof(struct vtinput_event));
vq_relchain(vq, event.idx, sizeof(struct vtinput_event));
}
done:
/* clear queue and send interrupt to guest */
vtinput_eventqueue_clear(queue);
vq_endchains(vq, 1);
return;
}
static int
vtinput_read_event_from_host(int fd, struct input_event *event)
{
const int len = read(fd, event, sizeof(struct input_event));
if (len != sizeof(struct input_event)) {
if (len == -1 && errno != EAGAIN) {
WPRINTF(("%s: event read failed! len = %d, errno = %d",
__func__, len, errno));
}
/* host doesn't have more events for us */
return (1);
}
return (0);
}
static void
vtinput_read_event(int fd __attribute((unused)),
enum ev_type t __attribute__((unused)), void *arg __attribute__((unused)))
{
struct pci_vtinput_softc *sc = arg;
/* skip if driver isn't ready */
if (!(sc->vsc_vs.vs_status & VIRTIO_CONFIG_STATUS_DRIVER_OK))
return;
/* read all events from host */
struct input_event event;
while (vtinput_read_event_from_host(sc->vsc_fd, &event) == 0) {
/* add events to our queue */
vtinput_eventqueue_add_event(&sc->vsc_eventqueue, &event);
/* only send events to guest on EV_SYN or SYN_REPORT */
if (event.type != EV_SYN || event.type != SYN_REPORT) {
continue;
}
/* send host events to guest */
vtinput_eventqueue_send_events(
&sc->vsc_eventqueue, &sc->vsc_queues[VTINPUT_EVENTQ]);
}
}
static int
pci_vtinput_legacy_config(nvlist_t *nvl, const char *opts)
{
if (opts == NULL)
return (-1);
/*
* parse opts:
* virtio-input,/dev/input/eventX
*/
char *cp = strchr(opts, ',');
if (cp == NULL) {
set_config_value_node(nvl, "path", opts);
return (0);
}
char *path = strndup(opts, cp - opts);
set_config_value_node(nvl, "path", path);
free(path);
return (pci_parse_legacy_config(nvl, cp + 1));
}
static int
pci_vtinput_init(struct vmctx *ctx, struct pci_devinst *pi, nvlist_t *nvl)
{
struct pci_vtinput_softc *sc;
/*
* Keep it here.
* Else it's possible to access it uninitialized by jumping to failed.
*/
pthread_mutexattr_t mtx_attr = NULL;
sc = calloc(1, sizeof(struct pci_vtinput_softc));
sc->vsc_evdev = get_config_value_node(nvl, "path");
if (sc->vsc_evdev == NULL) {
WPRINTF(("%s: missing required path config value", __func__));
goto failed;
}
/*
* open evdev by using non blocking I/O:
* read from /dev/input/eventX would block our thread otherwise
*/
sc->vsc_fd = open(sc->vsc_evdev, O_RDWR | O_NONBLOCK);
if (sc->vsc_fd < 0) {
WPRINTF(("%s: failed to open %s", __func__, sc->vsc_evdev));
goto failed;
}
/* check if evdev is really a evdev */
int evversion;
int error = ioctl(sc->vsc_fd, EVIOCGVERSION, &evversion);
if (error < 0) {
WPRINTF(("%s: %s is no evdev", __func__, sc->vsc_evdev));
goto failed;
}
/* gain exclusive access to evdev */
error = ioctl(sc->vsc_fd, EVIOCGRAB, 1);
if (error < 0) {
WPRINTF(("%s: failed to grab %s", __func__, sc->vsc_evdev));
goto failed;
}
if (pthread_mutexattr_init(&mtx_attr)) {
WPRINTF(("%s: init mutexattr failed", __func__));
goto failed;
}
if (pthread_mutexattr_settype(&mtx_attr, PTHREAD_MUTEX_RECURSIVE)) {
WPRINTF(("%s: settype mutexattr failed", __func__));
goto failed;
}
if (pthread_mutex_init(&sc->vsc_mtx, &mtx_attr)) {
WPRINTF(("%s: init mutex failed", __func__));
goto failed;
}
/* init softc */
sc->vsc_eventqueue.idx = 0;
sc->vsc_eventqueue.size = VTINPUT_MAX_PKT_LEN;
sc->vsc_eventqueue.events = calloc(
sc->vsc_eventqueue.size, sizeof(struct vtinput_event_elem));
sc->vsc_config_valid = 0;
if (sc->vsc_eventqueue.events == NULL) {
WPRINTF(("%s: failed to alloc eventqueue", __func__));
goto failed;
}
/* register event handler */
sc->vsc_evp = mevent_add(sc->vsc_fd, EVF_READ, vtinput_read_event, sc);
if (sc->vsc_evp == NULL) {
WPRINTF(("%s: could not register mevent", __func__));
goto failed;
}
#ifndef WITHOUT_CAPSICUM
cap_rights_t rights;
cap_rights_init(&rights, CAP_EVENT, CAP_IOCTL, CAP_READ, CAP_WRITE);
if (caph_rights_limit(sc->vsc_fd, &rights) == -1) {
errx(EX_OSERR, "Unable to apply rights for sandbox");
}
#endif
/* link virtio to softc */
vi_softc_linkup(
&sc->vsc_vs, &vtinput_vi_consts, sc, pi, sc->vsc_queues);
sc->vsc_vs.vs_mtx = &sc->vsc_mtx;
/* init virtio queues */
sc->vsc_queues[VTINPUT_EVENTQ].vq_qsize = VTINPUT_RINGSZ;
sc->vsc_queues[VTINPUT_EVENTQ].vq_notify = pci_vtinput_notify_eventq;
sc->vsc_queues[VTINPUT_STATUSQ].vq_qsize = VTINPUT_RINGSZ;
sc->vsc_queues[VTINPUT_STATUSQ].vq_notify = pci_vtinput_notify_statusq;
/* initialize config space */
pci_set_cfgdata16(pi, PCIR_DEVICE, VIRTIO_DEV_INPUT);
pci_set_cfgdata16(pi, PCIR_VENDOR, VIRTIO_VENDOR);
pci_set_cfgdata8(pi, PCIR_CLASS, PCIC_INPUTDEV);
pci_set_cfgdata8(pi, PCIR_SUBCLASS, PCIS_INPUTDEV_OTHER);
pci_set_cfgdata8(pi, PCIR_REVID, VIRTIO_REV_INPUT);
pci_set_cfgdata16(pi, PCIR_SUBDEV_0, VIRTIO_SUBDEV_INPUT);
pci_set_cfgdata16(pi, PCIR_SUBVEND_0, VIRTIO_SUBVEN_INPUT);
/* add MSI-X table BAR */
if (vi_intr_init(&sc->vsc_vs, 1, fbsdrun_virtio_msix()))
goto failed;
/* add virtio register */
vi_set_io_bar(&sc->vsc_vs, 0);
return (0);
failed:
if (sc == NULL) {
return (-1);
}
if (sc->vsc_evp)
mevent_delete(sc->vsc_evp);
if (sc->vsc_eventqueue.events)
free(sc->vsc_eventqueue.events);
if (sc->vsc_mtx)
pthread_mutex_destroy(&sc->vsc_mtx);
if (mtx_attr)
pthread_mutexattr_destroy(&mtx_attr);
if (sc->vsc_fd)
close(sc->vsc_fd);
free(sc);
return (-1);
}
struct pci_devemu pci_de_vinput = {
.pe_emu = "virtio-input",
.pe_init = pci_vtinput_init,
.pe_legacy_config = pci_vtinput_legacy_config,
.pe_barwrite = vi_pci_write,
.pe_barread = vi_pci_read,
};
PCI_EMUL_SET(pci_de_vinput);