- 根目录:
- drivers
- staging
- usbip
- stub_dev.c
/*
* Copyright (C) 2003-2008 Takahiro Hirofuchi
*
* This is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
* USA.
*/
#include <linux/device.h>
#include <linux/kthread.h>
#include <linux/module.h>
#include "usbip_common.h"
#include "stub.h"
/*
* Define device IDs here if you want to explicitly limit exportable devices.
* In most cases, wildcard matching will be okay because driver binding can be
* changed dynamically by a userland program.
*/
static struct usb_device_id stub_table[] = {
#if 0
/* just an example */
{ USB_DEVICE(0x05ac, 0x0301) }, /* Mac 1 button mouse */
{ USB_DEVICE(0x0430, 0x0009) }, /* Plat Home Keyboard */
{ USB_DEVICE(0x059b, 0x0001) }, /* Iomega USB Zip 100 */
{ USB_DEVICE(0x04b3, 0x4427) }, /* IBM USB CD-ROM */
{ USB_DEVICE(0x05a9, 0xa511) }, /* LifeView USB cam */
{ USB_DEVICE(0x55aa, 0x0201) }, /* Imation card reader */
{ USB_DEVICE(0x046d, 0x0870) }, /* Qcam Express(QV-30) */
{ USB_DEVICE(0x04bb, 0x0101) }, /* IO-DATA HD 120GB */
{ USB_DEVICE(0x04bb, 0x0904) }, /* IO-DATA USB-ET/TX */
{ USB_DEVICE(0x04bb, 0x0201) }, /* IO-DATA USB-ET/TX */
{ USB_DEVICE(0x08bb, 0x2702) }, /* ONKYO USB Speaker */
{ USB_DEVICE(0x046d, 0x08b2) }, /* Logicool Qcam 4000 Pro */
#endif
/* magic for wild card */
{ .driver_info = 1 },
{ 0, } /* Terminating entry */
};
MODULE_DEVICE_TABLE(usb, stub_table);
/*
* usbip_status shows the status of usbip-host as long as this driver is bound
* to the target device.
*/
static ssize_t show_status(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct stub_device *sdev = dev_get_drvdata(dev);
int status;
if (!sdev) {
dev_err(dev, "sdev is null\n");
return -ENODEV;
}
spin_lock(&sdev->ud.lock);
status = sdev->ud.status;
spin_unlock(&sdev->ud.lock);
return snprintf(buf, PAGE_SIZE, "%d\n", status);
}
static DEVICE_ATTR(usbip_status, S_IRUGO, show_status, NULL);
/*
* usbip_sockfd gets a socket descriptor of an established TCP connection that
* is used to transfer usbip requests by kernel threads. -1 is a magic number
* by which usbip connection is finished.
*/
static ssize_t store_sockfd(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
struct stub_device *sdev = dev_get_drvdata(dev);
int sockfd = 0;
struct socket *socket;
if (!sdev) {
dev_err(dev, "sdev is null\n");
return -ENODEV;
}
sscanf(buf, "%d", &sockfd);
if (sockfd != -1) {
dev_info(dev, "stub up\n");
spin_lock(&sdev->ud.lock);
if (sdev->ud.status != SDEV_ST_AVAILABLE) {
dev_err(dev, "not ready\n");
spin_unlock(&sdev->ud.lock);
return -EINVAL;
}
socket = sockfd_to_socket(sockfd);
if (!socket) {
spin_unlock(&sdev->ud.lock);
return -EINVAL;
}
sdev->ud.tcp_socket = socket;
spin_unlock(&sdev->ud.lock);
sdev->ud.tcp_rx = kthread_run(stub_rx_loop, &sdev->ud, "stub_rx");
sdev->ud.tcp_tx = kthread_run(stub_tx_loop, &sdev->ud, "stub_tx");
spin_lock(&sdev->ud.lock);
sdev->ud.status = SDEV_ST_USED;
spin_unlock(&sdev->ud.lock);
} else {
dev_info(dev, "stub down\n");
spin_lock(&sdev->ud.lock);
if (sdev->ud.status != SDEV_ST_USED) {
spin_unlock(&sdev->ud.lock);
return -EINVAL;
}
spin_unlock(&sdev->ud.lock);
usbip_event_add(&sdev->ud, SDEV_EVENT_DOWN);
}
return count;
}
static DEVICE_ATTR(usbip_sockfd, S_IWUSR, NULL, store_sockfd);
static int stub_add_files(struct device *dev)
{
int err = 0;
err = device_create_file(dev, &dev_attr_usbip_status);
if (err)
goto err_status;
err = device_create_file(dev, &dev_attr_usbip_sockfd);
if (err)
goto err_sockfd;
err = device_create_file(dev, &dev_attr_usbip_debug);
if (err)
goto err_debug;
return 0;
err_debug:
device_remove_file(dev, &dev_attr_usbip_sockfd);
err_sockfd:
device_remove_file(dev, &dev_attr_usbip_status);
err_status:
return err;
}
static void stub_remove_files(struct device *dev)
{
device_remove_file(dev, &dev_attr_usbip_status);
device_remove_file(dev, &dev_attr_usbip_sockfd);
device_remove_file(dev, &dev_attr_usbip_debug);
}
static void stub_shutdown_connection(struct usbip_device *ud)
{
struct stub_device *sdev = container_of(ud, struct stub_device, ud);
/*
* When removing an exported device, kernel panic sometimes occurred
* and then EIP was sk_wait_data of stub_rx thread. Is this because
* sk_wait_data returned though stub_rx thread was already finished by
* step 1?
*/
if (ud->tcp_socket) {
dev_dbg(&sdev->udev->dev, "shutdown tcp_socket %p\n",
ud->tcp_socket);
kernel_sock_shutdown(ud->tcp_socket, SHUT_RDWR);
}
/* 1. stop threads */
if (ud->tcp_rx && !task_is_dead(ud->tcp_rx))
kthread_stop(ud->tcp_rx);
if (ud->tcp_tx && !task_is_dead(ud->tcp_tx))
kthread_stop(ud->tcp_tx);
/*
* 2. close the socket
*
* tcp_socket is freed after threads are killed so that usbip_xmit does
* not touch NULL socket.
*/
if (ud->tcp_socket) {
sock_release(ud->tcp_socket);
ud->tcp_socket = NULL;
}
/* 3. free used data */
stub_device_cleanup_urbs(sdev);
/* 4. free stub_unlink */
{
unsigned long flags;
struct stub_unlink *unlink, *tmp;
spin_lock_irqsave(&sdev->priv_lock, flags);
list_for_each_entry_safe(unlink, tmp, &sdev->unlink_tx, list) {
list_del(&unlink->list);
kfree(unlink);
}
list_for_each_entry_safe(unlink, tmp, &sdev->unlink_free,
list) {
list_del(&unlink->list);
kfree(unlink);
}
spin_unlock_irqrestore(&sdev->priv_lock, flags);
}
}
static void stub_device_reset(struct usbip_device *ud)
{
struct stub_device *sdev = container_of(ud, struct stub_device, ud);
struct usb_device *udev = sdev->udev;
int ret;
dev_dbg(&udev->dev, "device reset");
ret = usb_lock_device_for_reset(udev, sdev->interface);
if (ret < 0) {
dev_err(&udev->dev, "lock for reset\n");
spin_lock(&ud->lock);
ud->status = SDEV_ST_ERROR;
spin_unlock(&ud->lock);
return;
}
/* try to reset the device */
ret = usb_reset_device(udev);
usb_unlock_device(udev);
spin_lock(&ud->lock);
if (ret) {
dev_err(&udev->dev, "device reset\n");
ud->status = SDEV_ST_ERROR;
} else {
dev_info(&udev->dev, "device reset\n");
ud->status = SDEV_ST_AVAILABLE;
}
spin_unlock(&ud->lock);
}
static void stub_device_unusable(struct usbip_device *ud)
{
spin_lock(&ud->lock);
ud->status = SDEV_ST_ERROR;
spin_unlock(&ud->lock);
}
/**
* stub_device_alloc - allocate a new stub_device struct
* @interface: usb_interface of a new device
*
* Allocates and initializes a new stub_device struct.
*/
static struct stub_device *stub_device_alloc(struct usb_device *udev,
struct usb_interface *interface)
{
struct stub_device *sdev;
int busnum = interface_to_busnum(interface);
int devnum = interface_to_devnum(interface);
dev_dbg(&interface->dev, "allocating stub device");
/* yes, it's a new device */
sdev = kzalloc(sizeof(struct stub_device), GFP_KERNEL);
if (!sdev) {
dev_err(&interface->dev, "no memory for stub_device\n");
return NULL;
}
sdev->interface = usb_get_intf(interface);
sdev->udev = usb_get_dev(udev);
/*
* devid is defined with devnum when this driver is first allocated.
* devnum may change later if a device is reset. However, devid never
* changes during a usbip connection.
*/
sdev->devid = (busnum << 16) | devnum;
sdev->ud.side = USBIP_STUB;
sdev->ud.status = SDEV_ST_AVAILABLE;
spin_lock_init(&sdev->ud.lock);
sdev->ud.tcp_socket = NULL;
INIT_LIST_HEAD(&sdev->priv_init);
INIT_LIST_HEAD(&sdev->priv_tx);
INIT_LIST_HEAD(&sdev->priv_free);
INIT_LIST_HEAD(&sdev->unlink_free);
INIT_LIST_HEAD(&sdev->unlink_tx);
spin_lock_init(&sdev->priv_lock);
init_waitqueue_head(&sdev->tx_waitq);
sdev->ud.eh_ops.shutdown = stub_shutdown_connection;
sdev->ud.eh_ops.reset = stub_device_reset;
sdev->ud.eh_ops.unusable = stub_device_unusable;
usbip_start_eh(&sdev->ud);
dev_dbg(&interface->dev, "register new interface\n");
return sdev;
}
static int stub_device_free(struct stub_device *sdev)
{
if (!sdev)
return -EINVAL;
kfree(sdev);
pr_debug("kfree udev ok\n");
return 0;
}
/*
* If a usb device has multiple active interfaces, this driver is bound to all
* the active interfaces. However, usbip exports *a* usb device (i.e., not *an*
* active interface). Currently, a userland program must ensure that it
* looks at the usbip's sysfs entries of only the first active interface.
*
* TODO: use "struct usb_device_driver" to bind a usb device.
* However, it seems it is not fully supported in mainline kernel yet
* (2.6.19.2).
*/
static int stub_probe(struct usb_interface *interface,
const struct usb_device_id *id)
{
struct usb_device *udev = interface_to_usbdev(interface);
struct stub_device *sdev = NULL;
const char *udev_busid = dev_name(interface->dev.parent);
int err = 0;
struct bus_id_priv *busid_priv;
dev_dbg(&interface->dev, "Enter\n");
/* check we should claim or not by busid_table */
busid_priv = get_busid_priv(udev_busid);
if (!busid_priv || (busid_priv->status == STUB_BUSID_REMOV) ||
(busid_priv->status == STUB_BUSID_OTHER)) {
dev_info(&interface->dev, "%s is not in match_busid table... "
"skip!\n", udev_busid);
/*
* Return value should be ENODEV or ENOXIO to continue trying
* other matched drivers by the driver core.
* See driver_probe_device() in driver/base/dd.c
*/
return -ENODEV;
}
if (udev->descriptor.bDeviceClass == USB_CLASS_HUB) {
dev_dbg(&udev->dev, "%s is a usb hub device... skip!\n",
udev_busid);
return -ENODEV;
}
if (!strcmp(udev->bus->bus_name, "vhci_hcd")) {
dev_dbg(&udev->dev, "%s is attached on vhci_hcd... skip!\n",
udev_busid);
return -ENODEV;
}
if (busid_priv->status == STUB_BUSID_ALLOC) {
sdev = busid_priv->sdev;
if (!sdev)
return -ENODEV;
busid_priv->interf_count++;
dev_info(&interface->dev, "usbip-host: register new interface "
"(bus %u dev %u ifn %u)\n",
udev->bus->busnum, udev->devnum,
interface->cur_altsetting->desc.bInterfaceNumber);
/* set private data to usb_interface */
usb_set_intfdata(interface, sdev);
err = stub_add_files(&interface->dev);
if (err) {
dev_err(&interface->dev, "stub_add_files for %s\n",
udev_busid);
usb_set_intfdata(interface, NULL);
busid_priv->interf_count--;
return err;
}
usb_get_intf(interface);
return 0;
}
/* ok, this is my device */
sdev = stub_device_alloc(udev, interface);
if (!sdev)
return -ENOMEM;
dev_info(&interface->dev, "usbip-host: register new device "
"(bus %u dev %u ifn %u)\n", udev->bus->busnum, udev->devnum,
interface->cur_altsetting->desc.bInterfaceNumber);
busid_priv->interf_count = 0;
busid_priv->shutdown_busid = 0;
/* set private data to usb_interface */
usb_set_intfdata(interface, sdev);
busid_priv->interf_count++;
busid_priv->sdev = sdev;
err = stub_add_files(&interface->dev);
if (err) {
dev_err(&interface->dev, "stub_add_files for %s\n", udev_busid);
usb_set_intfdata(interface, NULL);
usb_put_intf(interface);
busid_priv->interf_count = 0;
busid_priv->sdev = NULL;
stub_device_free(sdev);
return err;
}
busid_priv->status = STUB_BUSID_ALLOC;
return 0;
}
static void shutdown_busid(struct bus_id_priv *busid_priv)
{
if (busid_priv->sdev && !busid_priv->shutdown_busid) {
busid_priv->shutdown_busid = 1;
usbip_event_add(&busid_priv->sdev->ud, SDEV_EVENT_REMOVED);
/* 2. wait for the stop of the event handler */
usbip_stop_eh(&busid_priv->sdev->ud);
}
}
/*
* called in usb_disconnect() or usb_deregister()
* but only if actconfig(active configuration) exists
*/
static void stub_disconnect(struct usb_interface *interface)
{
struct stub_device *sdev;
const char *udev_busid = dev_name(interface->dev.parent);
struct bus_id_priv *busid_priv;
dev_dbg(&interface->dev, "Enter\n");
busid_priv = get_busid_priv(udev_busid);
if (!busid_priv) {
BUG();
return;
}
sdev = usb_get_intfdata(interface);
/* get stub_device */
if (!sdev) {
dev_err(&interface->dev, "could not get device");
/* BUG(); */
return;
}
usb_set_intfdata(interface, NULL);
/*
* NOTE:
* rx/tx threads are invoked for each usb_device.
*/
stub_remove_files(&interface->dev);
/*If usb reset called from event handler*/
if (busid_priv->sdev->ud.eh == current) {
busid_priv->interf_count--;
return;
}
if (busid_priv->interf_count > 1) {
busid_priv->interf_count--;
shutdown_busid(busid_priv);
usb_put_intf(interface);
return;
}
busid_priv->interf_count = 0;
/* 1. shutdown the current connection */
shutdown_busid(busid_priv);
usb_put_dev(sdev->udev);
usb_put_intf(interface);
/* 3. free sdev */
busid_priv->sdev = NULL;
stub_device_free(sdev);
if (busid_priv->status == STUB_BUSID_ALLOC) {
busid_priv->status = STUB_BUSID_ADDED;
} else {
busid_priv->status = STUB_BUSID_OTHER;
del_match_busid((char *)udev_busid);
}
}
/*
* Presence of pre_reset and post_reset prevents the driver from being unbound
* when the device is being reset
*/
int stub_pre_reset(struct usb_interface *interface)
{
dev_dbg(&interface->dev, "pre_reset\n");
return 0;
}
int stub_post_reset(struct usb_interface *interface)
{
dev_dbg(&interface->dev, "post_reset\n");
return 0;
}
struct usb_driver stub_driver = {
.name = "usbip-host",
.probe = stub_probe,
.disconnect = stub_disconnect,
.id_table = stub_table,
.pre_reset = stub_pre_reset,
.post_reset = stub_post_reset,
};