qemu-e2k/hw/usb/dev-serial.c
Daniel P. Berrange 6ab3fc32ea hw: replace most use of qemu_chr_fe_write with qemu_chr_fe_write_all
The qemu_chr_fe_write method will return -1 on EAGAIN if the
chardev backend write would block. Almost no callers of the
qemu_chr_fe_write() method check the return value, instead
blindly assuming data was successfully sent. In most cases
this will lead to silent data loss on interactive consoles,
but in some cases (eg RNG EGD) it'll just cause corruption
of the protocol being spoken.

We unfortunately can't fix the virtio-console code, due to
a bug in the Linux guest drivers, which would cause the
entire Linux kernel to hang if we delay processing of the
incoming data in any way. Fixing this requires first fixing
the guest driver to not hold spinlocks while writing to the
hvc device backend.

Fixes bug: https://bugs.launchpad.net/qemu/+bug/1586756

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1473170165-540-4-git-send-email-berrange@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-09-13 19:09:42 +02:00

655 lines
18 KiB
C

/*
* FTDI FT232BM Device emulation
*
* Copyright (c) 2006 CodeSourcery.
* Copyright (c) 2008 Samuel Thibault <samuel.thibault@ens-lyon.org>
* Written by Paul Brook, reused for FTDI by Samuel Thibault
*
* This code is licensed under the LGPL.
*/
#include "qemu/osdep.h"
#include "qapi/error.h"
#include "qemu-common.h"
#include "qemu/cutils.h"
#include "qemu/error-report.h"
#include "hw/usb.h"
#include "hw/usb/desc.h"
#include "sysemu/char.h"
//#define DEBUG_Serial
#ifdef DEBUG_Serial
#define DPRINTF(fmt, ...) \
do { printf("usb-serial: " fmt , ## __VA_ARGS__); } while (0)
#else
#define DPRINTF(fmt, ...) do {} while(0)
#endif
#define RECV_BUF 384
/* Commands */
#define FTDI_RESET 0
#define FTDI_SET_MDM_CTRL 1
#define FTDI_SET_FLOW_CTRL 2
#define FTDI_SET_BAUD 3
#define FTDI_SET_DATA 4
#define FTDI_GET_MDM_ST 5
#define FTDI_SET_EVENT_CHR 6
#define FTDI_SET_ERROR_CHR 7
#define FTDI_SET_LATENCY 9
#define FTDI_GET_LATENCY 10
#define DeviceOutVendor ((USB_DIR_OUT|USB_TYPE_VENDOR|USB_RECIP_DEVICE)<<8)
#define DeviceInVendor ((USB_DIR_IN |USB_TYPE_VENDOR|USB_RECIP_DEVICE)<<8)
/* RESET */
#define FTDI_RESET_SIO 0
#define FTDI_RESET_RX 1
#define FTDI_RESET_TX 2
/* SET_MDM_CTRL */
#define FTDI_DTR 1
#define FTDI_SET_DTR (FTDI_DTR << 8)
#define FTDI_RTS 2
#define FTDI_SET_RTS (FTDI_RTS << 8)
/* SET_FLOW_CTRL */
#define FTDI_RTS_CTS_HS 1
#define FTDI_DTR_DSR_HS 2
#define FTDI_XON_XOFF_HS 4
/* SET_DATA */
#define FTDI_PARITY (0x7 << 8)
#define FTDI_ODD (0x1 << 8)
#define FTDI_EVEN (0x2 << 8)
#define FTDI_MARK (0x3 << 8)
#define FTDI_SPACE (0x4 << 8)
#define FTDI_STOP (0x3 << 11)
#define FTDI_STOP1 (0x0 << 11)
#define FTDI_STOP15 (0x1 << 11)
#define FTDI_STOP2 (0x2 << 11)
/* GET_MDM_ST */
/* TODO: should be sent every 40ms */
#define FTDI_CTS (1<<4) // CTS line status
#define FTDI_DSR (1<<5) // DSR line status
#define FTDI_RI (1<<6) // RI line status
#define FTDI_RLSD (1<<7) // Receive Line Signal Detect
/* Status */
#define FTDI_DR (1<<0) // Data Ready
#define FTDI_OE (1<<1) // Overrun Err
#define FTDI_PE (1<<2) // Parity Err
#define FTDI_FE (1<<3) // Framing Err
#define FTDI_BI (1<<4) // Break Interrupt
#define FTDI_THRE (1<<5) // Transmitter Holding Register
#define FTDI_TEMT (1<<6) // Transmitter Empty
#define FTDI_FIFO (1<<7) // Error in FIFO
typedef struct {
USBDevice dev;
uint8_t recv_buf[RECV_BUF];
uint16_t recv_ptr;
uint16_t recv_used;
uint8_t event_chr;
uint8_t error_chr;
uint8_t event_trigger;
QEMUSerialSetParams params;
int latency; /* ms */
CharDriverState *cs;
} USBSerialState;
#define TYPE_USB_SERIAL "usb-serial-dev"
#define USB_SERIAL_DEV(obj) OBJECT_CHECK(USBSerialState, (obj), TYPE_USB_SERIAL)
enum {
STR_MANUFACTURER = 1,
STR_PRODUCT_SERIAL,
STR_PRODUCT_BRAILLE,
STR_SERIALNUMBER,
};
static const USBDescStrings desc_strings = {
[STR_MANUFACTURER] = "QEMU",
[STR_PRODUCT_SERIAL] = "QEMU USB SERIAL",
[STR_PRODUCT_BRAILLE] = "QEMU USB BAUM BRAILLE",
[STR_SERIALNUMBER] = "1",
};
static const USBDescIface desc_iface0 = {
.bInterfaceNumber = 0,
.bNumEndpoints = 2,
.bInterfaceClass = 0xff,
.bInterfaceSubClass = 0xff,
.bInterfaceProtocol = 0xff,
.eps = (USBDescEndpoint[]) {
{
.bEndpointAddress = USB_DIR_IN | 0x01,
.bmAttributes = USB_ENDPOINT_XFER_BULK,
.wMaxPacketSize = 64,
},{
.bEndpointAddress = USB_DIR_OUT | 0x02,
.bmAttributes = USB_ENDPOINT_XFER_BULK,
.wMaxPacketSize = 64,
},
}
};
static const USBDescDevice desc_device = {
.bcdUSB = 0x0200,
.bMaxPacketSize0 = 8,
.bNumConfigurations = 1,
.confs = (USBDescConfig[]) {
{
.bNumInterfaces = 1,
.bConfigurationValue = 1,
.bmAttributes = USB_CFG_ATT_ONE,
.bMaxPower = 50,
.nif = 1,
.ifs = &desc_iface0,
},
},
};
static const USBDesc desc_serial = {
.id = {
.idVendor = 0x0403,
.idProduct = 0x6001,
.bcdDevice = 0x0400,
.iManufacturer = STR_MANUFACTURER,
.iProduct = STR_PRODUCT_SERIAL,
.iSerialNumber = STR_SERIALNUMBER,
},
.full = &desc_device,
.str = desc_strings,
};
static const USBDesc desc_braille = {
.id = {
.idVendor = 0x0403,
.idProduct = 0xfe72,
.bcdDevice = 0x0400,
.iManufacturer = STR_MANUFACTURER,
.iProduct = STR_PRODUCT_BRAILLE,
.iSerialNumber = STR_SERIALNUMBER,
},
.full = &desc_device,
.str = desc_strings,
};
static void usb_serial_reset(USBSerialState *s)
{
/* TODO: Set flow control to none */
s->event_chr = 0x0d;
s->event_trigger = 0;
s->recv_ptr = 0;
s->recv_used = 0;
/* TODO: purge in char driver */
}
static void usb_serial_handle_reset(USBDevice *dev)
{
USBSerialState *s = (USBSerialState *)dev;
DPRINTF("Reset\n");
usb_serial_reset(s);
/* TODO: Reset char device, send BREAK? */
}
static uint8_t usb_get_modem_lines(USBSerialState *s)
{
int flags;
uint8_t ret;
if (qemu_chr_fe_ioctl(s->cs, CHR_IOCTL_SERIAL_GET_TIOCM, &flags) == -ENOTSUP)
return FTDI_CTS|FTDI_DSR|FTDI_RLSD;
ret = 0;
if (flags & CHR_TIOCM_CTS)
ret |= FTDI_CTS;
if (flags & CHR_TIOCM_DSR)
ret |= FTDI_DSR;
if (flags & CHR_TIOCM_RI)
ret |= FTDI_RI;
if (flags & CHR_TIOCM_CAR)
ret |= FTDI_RLSD;
return ret;
}
static void usb_serial_handle_control(USBDevice *dev, USBPacket *p,
int request, int value, int index, int length, uint8_t *data)
{
USBSerialState *s = (USBSerialState *)dev;
int ret;
DPRINTF("got control %x, value %x\n",request, value);
ret = usb_desc_handle_control(dev, p, request, value, index, length, data);
if (ret >= 0) {
return;
}
switch (request) {
case EndpointOutRequest | USB_REQ_CLEAR_FEATURE:
break;
/* Class specific requests. */
case DeviceOutVendor | FTDI_RESET:
switch (value) {
case FTDI_RESET_SIO:
usb_serial_reset(s);
break;
case FTDI_RESET_RX:
s->recv_ptr = 0;
s->recv_used = 0;
/* TODO: purge from char device */
break;
case FTDI_RESET_TX:
/* TODO: purge from char device */
break;
}
break;
case DeviceOutVendor | FTDI_SET_MDM_CTRL:
{
static int flags;
qemu_chr_fe_ioctl(s->cs,CHR_IOCTL_SERIAL_GET_TIOCM, &flags);
if (value & FTDI_SET_RTS) {
if (value & FTDI_RTS)
flags |= CHR_TIOCM_RTS;
else
flags &= ~CHR_TIOCM_RTS;
}
if (value & FTDI_SET_DTR) {
if (value & FTDI_DTR)
flags |= CHR_TIOCM_DTR;
else
flags &= ~CHR_TIOCM_DTR;
}
qemu_chr_fe_ioctl(s->cs,CHR_IOCTL_SERIAL_SET_TIOCM, &flags);
break;
}
case DeviceOutVendor | FTDI_SET_FLOW_CTRL:
/* TODO: ioctl */
break;
case DeviceOutVendor | FTDI_SET_BAUD: {
static const int subdivisors8[8] = { 0, 4, 2, 1, 3, 5, 6, 7 };
int subdivisor8 = subdivisors8[((value & 0xc000) >> 14)
| ((index & 1) << 2)];
int divisor = value & 0x3fff;
/* chip special cases */
if (divisor == 1 && subdivisor8 == 0)
subdivisor8 = 4;
if (divisor == 0 && subdivisor8 == 0)
divisor = 1;
s->params.speed = (48000000 / 2) / (8 * divisor + subdivisor8);
qemu_chr_fe_ioctl(s->cs, CHR_IOCTL_SERIAL_SET_PARAMS, &s->params);
break;
}
case DeviceOutVendor | FTDI_SET_DATA:
switch (value & FTDI_PARITY) {
case 0:
s->params.parity = 'N';
break;
case FTDI_ODD:
s->params.parity = 'O';
break;
case FTDI_EVEN:
s->params.parity = 'E';
break;
default:
DPRINTF("unsupported parity %d\n", value & FTDI_PARITY);
goto fail;
}
switch (value & FTDI_STOP) {
case FTDI_STOP1:
s->params.stop_bits = 1;
break;
case FTDI_STOP2:
s->params.stop_bits = 2;
break;
default:
DPRINTF("unsupported stop bits %d\n", value & FTDI_STOP);
goto fail;
}
qemu_chr_fe_ioctl(s->cs, CHR_IOCTL_SERIAL_SET_PARAMS, &s->params);
/* TODO: TX ON/OFF */
break;
case DeviceInVendor | FTDI_GET_MDM_ST:
data[0] = usb_get_modem_lines(s) | 1;
data[1] = 0;
p->actual_length = 2;
break;
case DeviceOutVendor | FTDI_SET_EVENT_CHR:
/* TODO: handle it */
s->event_chr = value;
break;
case DeviceOutVendor | FTDI_SET_ERROR_CHR:
/* TODO: handle it */
s->error_chr = value;
break;
case DeviceOutVendor | FTDI_SET_LATENCY:
s->latency = value;
break;
case DeviceInVendor | FTDI_GET_LATENCY:
data[0] = s->latency;
p->actual_length = 1;
break;
default:
fail:
DPRINTF("got unsupported/bogus control %x, value %x\n", request, value);
p->status = USB_RET_STALL;
break;
}
}
static void usb_serial_handle_data(USBDevice *dev, USBPacket *p)
{
USBSerialState *s = (USBSerialState *)dev;
uint8_t devep = p->ep->nr;
struct iovec *iov;
uint8_t header[2];
int i, first_len, len;
switch (p->pid) {
case USB_TOKEN_OUT:
if (devep != 2)
goto fail;
for (i = 0; i < p->iov.niov; i++) {
iov = p->iov.iov + i;
/* XXX this blocks entire thread. Rewrite to use
* qemu_chr_fe_write and background I/O callbacks */
qemu_chr_fe_write_all(s->cs, iov->iov_base, iov->iov_len);
}
p->actual_length = p->iov.size;
break;
case USB_TOKEN_IN:
if (devep != 1)
goto fail;
first_len = RECV_BUF - s->recv_ptr;
len = p->iov.size;
if (len <= 2) {
p->status = USB_RET_NAK;
break;
}
header[0] = usb_get_modem_lines(s) | 1;
/* We do not have the uart details */
/* handle serial break */
if (s->event_trigger && s->event_trigger & FTDI_BI) {
s->event_trigger &= ~FTDI_BI;
header[1] = FTDI_BI;
usb_packet_copy(p, header, 2);
break;
} else {
header[1] = 0;
}
len -= 2;
if (len > s->recv_used)
len = s->recv_used;
if (!len) {
p->status = USB_RET_NAK;
break;
}
if (first_len > len)
first_len = len;
usb_packet_copy(p, header, 2);
usb_packet_copy(p, s->recv_buf + s->recv_ptr, first_len);
if (len > first_len)
usb_packet_copy(p, s->recv_buf, len - first_len);
s->recv_used -= len;
s->recv_ptr = (s->recv_ptr + len) % RECV_BUF;
break;
default:
DPRINTF("Bad token\n");
fail:
p->status = USB_RET_STALL;
break;
}
}
static int usb_serial_can_read(void *opaque)
{
USBSerialState *s = opaque;
if (!s->dev.attached) {
return 0;
}
return RECV_BUF - s->recv_used;
}
static void usb_serial_read(void *opaque, const uint8_t *buf, int size)
{
USBSerialState *s = opaque;
int first_size, start;
/* room in the buffer? */
if (size > (RECV_BUF - s->recv_used))
size = RECV_BUF - s->recv_used;
start = s->recv_ptr + s->recv_used;
if (start < RECV_BUF) {
/* copy data to end of buffer */
first_size = RECV_BUF - start;
if (first_size > size)
first_size = size;
memcpy(s->recv_buf + start, buf, first_size);
/* wrap around to front if needed */
if (size > first_size)
memcpy(s->recv_buf, buf + first_size, size - first_size);
} else {
start -= RECV_BUF;
memcpy(s->recv_buf + start, buf, size);
}
s->recv_used += size;
}
static void usb_serial_event(void *opaque, int event)
{
USBSerialState *s = opaque;
switch (event) {
case CHR_EVENT_BREAK:
s->event_trigger |= FTDI_BI;
break;
case CHR_EVENT_FOCUS:
break;
case CHR_EVENT_OPENED:
if (!s->dev.attached) {
usb_device_attach(&s->dev, &error_abort);
}
break;
case CHR_EVENT_CLOSED:
if (s->dev.attached) {
usb_device_detach(&s->dev);
}
break;
}
}
static void usb_serial_realize(USBDevice *dev, Error **errp)
{
USBSerialState *s = USB_SERIAL_DEV(dev);
Error *local_err = NULL;
usb_desc_create_serial(dev);
usb_desc_init(dev);
dev->auto_attach = 0;
if (!s->cs) {
error_setg(errp, "Property chardev is required");
return;
}
usb_check_attach(dev, &local_err);
if (local_err) {
error_propagate(errp, local_err);
return;
}
qemu_chr_add_handlers(s->cs, usb_serial_can_read, usb_serial_read,
usb_serial_event, s);
usb_serial_handle_reset(dev);
if (s->cs->be_open && !dev->attached) {
usb_device_attach(dev, &error_abort);
}
}
static USBDevice *usb_serial_init(USBBus *bus, const char *filename)
{
USBDevice *dev;
CharDriverState *cdrv;
uint32_t vendorid = 0, productid = 0;
char label[32];
static int index;
while (*filename && *filename != ':') {
const char *p;
char *e;
if (strstart(filename, "vendorid=", &p)) {
vendorid = strtol(p, &e, 16);
if (e == p || (*e && *e != ',' && *e != ':')) {
error_report("bogus vendor ID %s", p);
return NULL;
}
filename = e;
} else if (strstart(filename, "productid=", &p)) {
productid = strtol(p, &e, 16);
if (e == p || (*e && *e != ',' && *e != ':')) {
error_report("bogus product ID %s", p);
return NULL;
}
filename = e;
} else {
error_report("unrecognized serial USB option %s", filename);
return NULL;
}
while(*filename == ',')
filename++;
}
if (!*filename) {
error_report("character device specification needed");
return NULL;
}
filename++;
snprintf(label, sizeof(label), "usbserial%d", index++);
cdrv = qemu_chr_new(label, filename, NULL);
if (!cdrv)
return NULL;
dev = usb_create(bus, "usb-serial");
qdev_prop_set_chr(&dev->qdev, "chardev", cdrv);
if (vendorid)
qdev_prop_set_uint16(&dev->qdev, "vendorid", vendorid);
if (productid)
qdev_prop_set_uint16(&dev->qdev, "productid", productid);
return dev;
}
static USBDevice *usb_braille_init(USBBus *bus, const char *unused)
{
USBDevice *dev;
CharDriverState *cdrv;
cdrv = qemu_chr_new("braille", "braille", NULL);
if (!cdrv)
return NULL;
dev = usb_create(bus, "usb-braille");
qdev_prop_set_chr(&dev->qdev, "chardev", cdrv);
return dev;
}
static const VMStateDescription vmstate_usb_serial = {
.name = "usb-serial",
.unmigratable = 1,
};
static Property serial_properties[] = {
DEFINE_PROP_CHR("chardev", USBSerialState, cs),
DEFINE_PROP_END_OF_LIST(),
};
static void usb_serial_dev_class_init(ObjectClass *klass, void *data)
{
DeviceClass *dc = DEVICE_CLASS(klass);
USBDeviceClass *uc = USB_DEVICE_CLASS(klass);
uc->realize = usb_serial_realize;
uc->handle_reset = usb_serial_handle_reset;
uc->handle_control = usb_serial_handle_control;
uc->handle_data = usb_serial_handle_data;
dc->vmsd = &vmstate_usb_serial;
set_bit(DEVICE_CATEGORY_INPUT, dc->categories);
}
static const TypeInfo usb_serial_dev_type_info = {
.name = TYPE_USB_SERIAL,
.parent = TYPE_USB_DEVICE,
.instance_size = sizeof(USBSerialState),
.abstract = true,
.class_init = usb_serial_dev_class_init,
};
static void usb_serial_class_initfn(ObjectClass *klass, void *data)
{
DeviceClass *dc = DEVICE_CLASS(klass);
USBDeviceClass *uc = USB_DEVICE_CLASS(klass);
uc->product_desc = "QEMU USB Serial";
uc->usb_desc = &desc_serial;
dc->props = serial_properties;
}
static const TypeInfo serial_info = {
.name = "usb-serial",
.parent = TYPE_USB_SERIAL,
.class_init = usb_serial_class_initfn,
};
static Property braille_properties[] = {
DEFINE_PROP_CHR("chardev", USBSerialState, cs),
DEFINE_PROP_END_OF_LIST(),
};
static void usb_braille_class_initfn(ObjectClass *klass, void *data)
{
DeviceClass *dc = DEVICE_CLASS(klass);
USBDeviceClass *uc = USB_DEVICE_CLASS(klass);
uc->product_desc = "QEMU USB Braille";
uc->usb_desc = &desc_braille;
dc->props = braille_properties;
}
static const TypeInfo braille_info = {
.name = "usb-braille",
.parent = TYPE_USB_SERIAL,
.class_init = usb_braille_class_initfn,
};
static void usb_serial_register_types(void)
{
type_register_static(&usb_serial_dev_type_info);
type_register_static(&serial_info);
usb_legacy_register("usb-serial", "serial", usb_serial_init);
type_register_static(&braille_info);
usb_legacy_register("usb-braille", "braille", usb_braille_init);
}
type_init(usb_serial_register_types)