/*
* USB Mass Storage Device emulation
*
* Copyright (c) 2006 CodeSourcery.
* Written by Paul Brook
*
* This code is licenced under the LGPL.
*/
#include "qemu-common.h"
#include "usb.h"
#include "block.h"
#include "scsi-disk.h"
#include "console.h"
//#define DEBUG_MSD
#ifdef DEBUG_MSD
#define DPRINTF(fmt, ...) \
do { printf("usb-msd: " fmt , ## __VA_ARGS__); } while (0)
#else
#define DPRINTF(fmt, ...) do {} while(0)
#endif
/* USB requests. */
#define MassStorageReset 0xff
#define GetMaxLun 0xfe
enum USBMSDMode {
USB_MSDM_CBW, /* Command Block. */
USB_MSDM_DATAOUT, /* Tranfer data to device. */
USB_MSDM_DATAIN, /* Transfer data from device. */
USB_MSDM_CSW /* Command Status. */
};
typedef struct {
USBDevice dev;
enum USBMSDMode mode;
uint32_t scsi_len;
uint8_t *scsi_buf;
uint32_t usb_len;
uint8_t *usb_buf;
uint32_t data_len;
uint32_t residue;
uint32_t tag;
BlockDriverState *bs;
SCSIDevice *scsi_dev;
int result;
/* For async completion. */
USBPacket *packet;
} MSDState;
struct usb_msd_cbw {
uint32_t sig;
uint32_t tag;
uint32_t data_len;
uint8_t flags;
uint8_t lun;
uint8_t cmd_len;
uint8_t cmd[16];
};
struct usb_msd_csw {
uint32_t sig;
uint32_t tag;
uint32_t residue;
uint8_t status;
};
static const uint8_t qemu_msd_dev_descriptor[] = {
0x12, /* u8 bLength; */
0x01, /* u8 bDescriptorType; Device */
0x00, 0x01, /* u16 bcdUSB; v1.0 */
0x00, /* u8 bDeviceClass; */
0x00, /* u8 bDeviceSubClass; */
0x00, /* u8 bDeviceProtocol; [ low/full speeds only ] */
0x08, /* u8 bMaxPacketSize0; 8 Bytes */
/* Vendor and product id are arbitrary. */
0x00, 0x00, /* u16 idVendor; */
0x00, 0x00, /* u16 idProduct; */
0x00, 0x00, /* u16 bcdDevice */
0x01, /* u8 iManufacturer; */
0x02, /* u8 iProduct; */
0x03, /* u8 iSerialNumber; */
0x01 /* u8 bNumConfigurations; */
};
static const uint8_t qemu_msd_config_descriptor[] = {
/* one configuration */
0x09, /* u8 bLength; */
0x02, /* u8 bDescriptorType; Configuration */
0x20, 0x00, /* u16 wTotalLength; */
0x01, /* u8 bNumInterfaces; (1) */
0x01, /* u8 bConfigurationValue; */
0x00, /* u8 iConfiguration; */
0xc0, /* u8 bmAttributes;
Bit 7: must be set,
6: Self-powered,
5: Remote wakeup,
4..0: resvd */
0x00, /* u8 MaxPower; */
/* one interface */
0x09, /* u8 if_bLength; */
0x04, /* u8 if_bDescriptorType; Interface */
0x00, /* u8 if_bInterfaceNumber; */
0x00, /* u8 if_bAlternateSetting; */
0x02, /* u8 if_bNumEndpoints; */
0x08, /* u8 if_bInterfaceClass; MASS STORAGE */
0x06, /* u8 if_bInterfaceSubClass; SCSI */
0x50, /* u8 if_bInterfaceProtocol; Bulk Only */
0x00, /* u8 if_iInterface; */
/* Bulk-In endpoint */
0x07, /* u8 ep_bLength; */
0x05, /* u8 ep_bDescriptorType; Endpoint */
0x81, /* u8 ep_bEndpointAddress; IN Endpoint 1 */
0x02, /* u8 ep_bmAttributes; Bulk */
0x40, 0x00, /* u16 ep_wMaxPacketSize; */
0x00, /* u8 ep_bInterval; */
/* Bulk-Out endpoint */
0x07, /* u8 ep_bLength; */
0x05, /* u8 ep_bDescriptorType; Endpoint */
0x02, /* u8 ep_bEndpointAddress; OUT Endpoint 2 */
0x02, /* u8 ep_bmAttributes; Bulk */
0x40, 0x00, /* u16 ep_wMaxPacketSize; */
0x00 /* u8 ep_bInterval; */
};
static void usb_msd_copy_data(MSDState *s)
{
uint32_t len;
len = s->usb_len;
if (len > s->scsi_len)
len = s->scsi_len;
if (s->mode == USB_MSDM_DATAIN) {
memcpy(s->usb_buf, s->scsi_buf, len);
} else {
memcpy(s->scsi_buf, s->usb_buf, len);
}
s->usb_len -= len;
s->scsi_len -= len;
s->usb_buf += len;
s->scsi_buf += len;
s->data_len -= len;
if (s->scsi_len == 0) {
if (s->mode == USB_MSDM_DATAIN) {
s->scsi_dev->read_data(s->scsi_dev, s->tag);
} else if (s->mode == USB_MSDM_DATAOUT) {
s->scsi_dev->write_data(s->scsi_dev, s->tag);
}
}
}
static void usb_msd_send_status(MSDState *s)
{
struct usb_msd_csw csw;
csw.sig = cpu_to_le32(0x53425355);
csw.tag = cpu_to_le32(s->tag);
csw.residue = s->residue;
csw.status = s->result;
memcpy(s->usb_buf, &csw, 13);
}
static void usb_msd_command_complete(void *opaque, int reason, uint32_t tag,
uint32_t arg)
{
MSDState *s = (MSDState *)opaque;
USBPacket *p = s->packet;
if (tag != s->tag) {
fprintf(stderr, "usb-msd: Unexpected SCSI Tag 0x%x\n", tag);
}
if (reason == SCSI_REASON_DONE) {
DPRINTF("Command complete %d\n", arg);
s->residue = s->data_len;
s->result = arg != 0;
if (s->packet) {
if (s->data_len == 0 && s->mode == USB_MSDM_DATAOUT) {
/* A deferred packet with no write data remaining must be
the status read packet. */
usb_msd_send_status(s);
s->mode = USB_MSDM_CBW;
} else {
if (s->data_len) {
s->data_len -= s->usb_len;
if (s->mode == USB_MSDM_DATAIN)
memset(s->usb_buf, 0, s->usb_len);
s->usb_len = 0;
}
if (s->data_len == 0)
s->mode = USB_MSDM_CSW;
}
s->packet = NULL;
usb_packet_complete(p);
} else if (s->data_len == 0) {
s->mode = USB_MSDM_CSW;
}
return;
}
s->scsi_len = arg;
s->scsi_buf = s->scsi_dev->get_buf(s->scsi_dev, tag);
if (p) {
usb_msd_copy_data(s);
if (s->usb_len == 0) {
/* Set s->packet to NULL before calling usb_packet_complete
because annother request may be issued before
usb_packet_complete returns. */
DPRINTF("Packet complete %p\n", p);
s->packet = NULL;
usb_packet_complete(p);
}
}
}
static void usb_msd_handle_reset(USBDevice *dev)
{
MSDState *s = (MSDState *)dev;
DPRINTF("Reset\n");
s->mode = USB_MSDM_CBW;
}
static int usb_msd_handle_control(USBDevice *dev, int request, int value,
int index, int length, uint8_t *data)
{
MSDState *s = (MSDState *)dev;
int ret = 0;
switch (request) {
case DeviceRequest | USB_REQ_GET_STATUS:
data[0] = (1 << USB_DEVICE_SELF_POWERED) |
(dev->remote_wakeup << USB_DEVICE_REMOTE_WAKEUP);
data[1] = 0x00;
ret = 2;
break;
case DeviceOutRequest | USB_REQ_CLEAR_FEATURE:
if (value == USB_DEVICE_REMOTE_WAKEUP) {
dev->remote_wakeup = 0;
} else {
goto fail;
}
ret = 0;
break;
case DeviceOutRequest | USB_REQ_SET_FEATURE:
if (value == USB_DEVICE_REMOTE_WAKEUP) {
dev->remote_wakeup = 1;
} else {
goto fail;
}
ret = 0;
break;
case DeviceOutRequest | USB_REQ_SET_ADDRESS:
dev->addr = value;
ret = 0;
break;
case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
switch(value >> 8) {
case USB_DT_DEVICE:
memcpy(data, qemu_msd_dev_descriptor,
sizeof(qemu_msd_dev_descriptor));
ret = sizeof(qemu_msd_dev_descriptor);
break;
case USB_DT_CONFIG:
memcpy(data, qemu_msd_config_descriptor,
sizeof(qemu_msd_config_descriptor));
ret = sizeof(qemu_msd_config_descriptor);
break;
case USB_DT_STRING:
switch(value & 0xff) {
case 0:
/* language ids */
data[0] = 4;
data[1] = 3;
data[2] = 0x09;
data[3] = 0x04;
ret = 4;
break;
case 1:
/* vendor description */
ret = set_usb_string(data, "QEMU " QEMU_VERSION);
break;
case 2:
/* product description */
ret = set_usb_string(data, "QEMU USB HARDDRIVE");
break;
case 3:
/* serial number */
ret = set_usb_string(data, "1");
break;
default:
goto fail;
}
break;
default:
goto fail;
}
break;
case DeviceRequest | USB_REQ_GET_CONFIGURATION:
data[0] = 1;
ret = 1;
break;
case DeviceOutRequest | USB_REQ_SET_CONFIGURATION:
ret = 0;
break;
case DeviceRequest | USB_REQ_GET_INTERFACE:
data[0] = 0;
ret = 1;
break;
case DeviceOutRequest | USB_REQ_SET_INTERFACE:
ret = 0;
break;
case EndpointOutRequest | USB_REQ_CLEAR_FEATURE:
if (value == 0 && index != 0x81) { /* clear ep halt */
goto fail;
}
ret = 0;
break;
/* Class specific requests. */
case MassStorageReset:
/* Reset state ready for the next CBW. */
s->mode = USB_MSDM_CBW;
ret = 0;
break;
case GetMaxLun:
data[0] = 0;
ret = 1;
break;
default:
fail:
ret = USB_RET_STALL;
break;
}
return ret;
}
static void usb_msd_cancel_io(USBPacket *p, void *opaque)
{
MSDState *s = opaque;
s->scsi_dev->cancel_io(s->scsi_dev, s->tag);
s->packet = NULL;
s->scsi_len = 0;
}
static int usb_msd_handle_data(USBDevice *dev, USBPacket *p)
{
MSDState *s = (MSDState *)dev;
int ret = 0;
struct usb_msd_cbw cbw;
uint8_t devep = p->devep;
uint8_t *data = p->data;
int len = p->len;
switch (p->pid) {
case USB_TOKEN_OUT:
if (devep != 2)
goto fail;
switch (s->mode) {
case USB_MSDM_CBW:
if (len != 31) {
fprintf(stderr, "usb-msd: Bad CBW size");
goto fail;
}
memcpy(&cbw, data, 31);
if (le32_to_cpu(cbw.sig) != 0x43425355) {
fprintf(stderr, "usb-msd: Bad signature %08x\n",
le32_to_cpu(cbw.sig));
goto fail;
}
DPRINTF("Command on LUN %d\n", cbw.lun);
if (cbw.lun != 0) {
fprintf(stderr, "usb-msd: Bad LUN %d\n", cbw.lun);
goto fail;
}
s->tag = le32_to_cpu(cbw.tag);
s->data_len = le32_to_cpu(cbw.data_len);
if (s->data_len == 0) {
s->mode = USB_MSDM_CSW;
} else if (cbw.flags & 0x80) {
s->mode = USB_MSDM_DATAIN;
} else {
s->mode = USB_MSDM_DATAOUT;
}
DPRINTF("Command tag 0x%x flags %08x len %d data %d\n",
s->tag, cbw.flags, cbw.cmd_len, s->data_len);
s->residue = 0;
s->scsi_dev->send_command(s->scsi_dev, s->tag, cbw.cmd, 0);
/* ??? Should check that USB and SCSI data transfer
directions match. */
if (s->residue == 0) {
if (s->mode == USB_MSDM_DATAIN) {
s->scsi_dev->read_data(s->scsi_dev, s->tag);
} else if (s->mode == USB_MSDM_DATAOUT) {
s->scsi_dev->write_data(s->scsi_dev, s->tag);
}
}
ret = len;
break;
case USB_MSDM_DATAOUT:
DPRINTF("Data out %d/%d\n", len, s->data_len);
if (len > s->data_len)
goto fail;
s->usb_buf = data;
s->usb_len = len;
if (s->scsi_len) {
usb_msd_copy_data(s);
}
if (s->residue && s->usb_len) {
s->data_len -= s->usb_len;
if (s->data_len == 0)
s->mode = USB_MSDM_CSW;
s->usb_len = 0;
}
if (s->usb_len) {
DPRINTF("Deferring packet %p\n", p);
usb_defer_packet(p, usb_msd_cancel_io, s);
s->packet = p;
ret = USB_RET_ASYNC;
} else {
ret = len;
}
break;
default:
DPRINTF("Unexpected write (len %d)\n", len);
goto fail;
}
break;
case USB_TOKEN_IN:
if (devep != 1)
goto fail;
switch (s->mode) {
case USB_MSDM_DATAOUT:
if (s->data_len != 0 || len < 13)
goto fail;
/* Waiting for SCSI write to complete. */
usb_defer_packet(p, usb_msd_cancel_io, s);
s->packet = p;
ret = USB_RET_ASYNC;
break;
case USB_MSDM_CSW:
DPRINTF("Command status %d tag 0x%x, len %d\n",
s->result, s->tag, len);
if (len < 13)
goto fail;
s->usb_len = len;
s->usb_buf = data;
usb_msd_send_status(s);
s->mode = USB_MSDM_CBW;
ret = 13;
break;
case USB_MSDM_DATAIN:
DPRINTF("Data in %d/%d\n", len, s->data_len);
if (len > s->data_len)
len = s->data_len;
s->usb_buf = data;
s->usb_len = len;
if (s->scsi_len) {
usb_msd_copy_data(s);
}
if (s->residue && s->usb_len) {
s->data_len -= s->usb_len;
memset(s->usb_buf, 0, s->usb_len);
if (s->data_len == 0)
s->mode = USB_MSDM_CSW;
s->usb_len = 0;
}
if (s->usb_len) {
DPRINTF("Deferring packet %p\n", p);
usb_defer_packet(p, usb_msd_cancel_io, s);
s->packet = p;
ret = USB_RET_ASYNC;
} else {
ret = len;
}
break;
default:
DPRINTF("Unexpected read (len %d)\n", len);
goto fail;
}
break;
default:
DPRINTF("Bad token\n");
fail:
ret = USB_RET_STALL;
break;
}
return ret;
}
static void usb_msd_handle_destroy(USBDevice *dev)
{
MSDState *s = (MSDState *)dev;
s->scsi_dev->destroy(s->scsi_dev);
bdrv_delete(s->bs);
qemu_free(s);
}
USBDevice *usb_msd_init(const char *filename)
{
MSDState *s;
BlockDriverState *bdrv;
BlockDriver *drv = NULL;
const char *p1;
char fmt[32];
p1 = strchr(filename, ':');
if (p1++) {
const char *p2;
if (strstart(filename, "format=", &p2)) {
int len = MIN(p1 - p2, sizeof(fmt));
pstrcpy(fmt, len, p2);
drv = bdrv_find_format(fmt);
if (!drv) {
printf("invalid format %s\n", fmt);
return NULL;
}
} else if (*filename != ':') {
printf("unrecognized USB mass-storage option %s\n", filename);
return NULL;
}
filename = p1;
}
if (!*filename) {
printf("block device specification needed\n");
return NULL;
}
s = qemu_mallocz(sizeof(MSDState));
bdrv = bdrv_new("usb");
if (bdrv_open(bdrv, filename, 0, drv) < 0)
goto fail;
s->bs = bdrv;
s->dev.speed = USB_SPEED_FULL;
s->dev.handle_packet = usb_generic_handle_packet;
s->dev.handle_reset = usb_msd_handle_reset;
s->dev.handle_control = usb_msd_handle_control;
s->dev.handle_data = usb_msd_handle_data;
s->dev.handle_destroy = usb_msd_handle_destroy;
snprintf(s->dev.devname, sizeof(s->dev.devname), "QEMU USB MSD(%.16s)",
filename);
s->scsi_dev = scsi_disk_init(bdrv, 0, usb_msd_command_complete, s);
usb_msd_handle_reset((USBDevice *)s);
return (USBDevice *)s;
fail:
qemu_free(s);
return NULL;
}
BlockDriverState *usb_msd_get_bdrv(USBDevice *dev)
{
MSDState *s = (MSDState *)dev;
return s->bs;
}