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path: root/drivers/usb/usbip/stub_dev.c
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Diffstat (limited to 'drivers/usb/usbip/stub_dev.c')
-rw-r--r--drivers/usb/usbip/stub_dev.c502
1 files changed, 502 insertions, 0 deletions
diff --git a/drivers/usb/usbip/stub_dev.c b/drivers/usb/usbip/stub_dev.c
new file mode 100644
index 000000000..a3ec49bdc
--- /dev/null
+++ b/drivers/usb/usbip/stub_dev.c
@@ -0,0 +1,502 @@
+/*
+ * 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/file.h>
+#include <linux/kthread.h>
+#include <linux/module.h>
+
+#include "usbip_common.h"
+#include "stub.h"
+
+/*
+ * usbip_status shows the status of usbip-host as long as this driver is bound
+ * to the target device.
+ */
+static ssize_t usbip_status_show(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_irq(&sdev->ud.lock);
+ status = sdev->ud.status;
+ spin_unlock_irq(&sdev->ud.lock);
+
+ return snprintf(buf, PAGE_SIZE, "%d\n", status);
+}
+static DEVICE_ATTR_RO(usbip_status);
+
+/*
+ * 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;
+ int rv;
+
+ if (!sdev) {
+ dev_err(dev, "sdev is null\n");
+ return -ENODEV;
+ }
+
+ rv = sscanf(buf, "%d", &sockfd);
+ if (rv != 1)
+ return -EINVAL;
+
+ if (sockfd != -1) {
+ int err;
+
+ dev_info(dev, "stub up\n");
+
+ spin_lock_irq(&sdev->ud.lock);
+
+ if (sdev->ud.status != SDEV_ST_AVAILABLE) {
+ dev_err(dev, "not ready\n");
+ goto err;
+ }
+
+ socket = sockfd_lookup(sockfd, &err);
+ if (!socket)
+ goto err;
+
+ sdev->ud.tcp_socket = socket;
+
+ spin_unlock_irq(&sdev->ud.lock);
+
+ sdev->ud.tcp_rx = kthread_get_run(stub_rx_loop, &sdev->ud,
+ "stub_rx");
+ sdev->ud.tcp_tx = kthread_get_run(stub_tx_loop, &sdev->ud,
+ "stub_tx");
+
+ spin_lock_irq(&sdev->ud.lock);
+ sdev->ud.status = SDEV_ST_USED;
+ spin_unlock_irq(&sdev->ud.lock);
+
+ } else {
+ dev_info(dev, "stub down\n");
+
+ spin_lock_irq(&sdev->ud.lock);
+ if (sdev->ud.status != SDEV_ST_USED)
+ goto err;
+
+ spin_unlock_irq(&sdev->ud.lock);
+
+ usbip_event_add(&sdev->ud, SDEV_EVENT_DOWN);
+ }
+
+ return count;
+
+err:
+ spin_unlock_irq(&sdev->ud.lock);
+ return -EINVAL;
+}
+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) {
+ kthread_stop_put(ud->tcp_rx);
+ ud->tcp_rx = NULL;
+ }
+ if (ud->tcp_tx) {
+ kthread_stop_put(ud->tcp_tx);
+ ud->tcp_tx = NULL;
+ }
+
+ /*
+ * 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) {
+ sockfd_put(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_irq(&ud->lock);
+ ud->status = SDEV_ST_ERROR;
+ spin_unlock_irq(&ud->lock);
+ return;
+ }
+
+ /* try to reset the device */
+ ret = usb_reset_device(udev);
+ usb_unlock_device(udev);
+
+ spin_lock_irq(&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_irq(&ud->lock);
+}
+
+static void stub_device_unusable(struct usbip_device *ud)
+{
+ spin_lock_irq(&ud->lock);
+ ud->status = SDEV_ST_ERROR;
+ spin_unlock_irq(&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 stub_device *sdev;
+ int busnum = udev->bus->busnum;
+ int devnum = udev->devnum;
+
+ dev_dbg(&udev->dev, "allocating stub device");
+
+ /* yes, it's a new device */
+ sdev = kzalloc(sizeof(struct stub_device), GFP_KERNEL);
+ if (!sdev)
+ return NULL;
+
+ 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(&udev->dev, "register new device\n");
+
+ return sdev;
+}
+
+static void stub_device_free(struct stub_device *sdev)
+{
+ kfree(sdev);
+}
+
+static int stub_probe(struct usb_device *udev)
+{
+ struct stub_device *sdev = NULL;
+ const char *udev_busid = dev_name(&udev->dev);
+ struct bus_id_priv *busid_priv;
+ int rc;
+
+ dev_dbg(&udev->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(&udev->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;
+ }
+
+ /* ok, this is my device */
+ sdev = stub_device_alloc(udev);
+ if (!sdev)
+ return -ENOMEM;
+
+ dev_info(&udev->dev,
+ "usbip-host: register new device (bus %u dev %u)\n",
+ udev->bus->busnum, udev->devnum);
+
+ busid_priv->shutdown_busid = 0;
+
+ /* set private data to usb_device */
+ dev_set_drvdata(&udev->dev, sdev);
+ busid_priv->sdev = sdev;
+ busid_priv->udev = udev;
+
+ /*
+ * Claim this hub port.
+ * It doesn't matter what value we pass as owner
+ * (struct dev_state) as long as it is unique.
+ */
+ rc = usb_hub_claim_port(udev->parent, udev->portnum,
+ (struct usb_dev_state *) udev);
+ if (rc) {
+ dev_dbg(&udev->dev, "unable to claim port\n");
+ goto err_port;
+ }
+
+ rc = stub_add_files(&udev->dev);
+ if (rc) {
+ dev_err(&udev->dev, "stub_add_files for %s\n", udev_busid);
+ goto err_files;
+ }
+ busid_priv->status = STUB_BUSID_ALLOC;
+
+ return 0;
+err_files:
+ usb_hub_release_port(udev->parent, udev->portnum,
+ (struct usb_dev_state *) udev);
+err_port:
+ dev_set_drvdata(&udev->dev, NULL);
+ usb_put_dev(udev);
+ kthread_stop_put(sdev->ud.eh);
+
+ busid_priv->sdev = NULL;
+ stub_device_free(sdev);
+ return rc;
+}
+
+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);
+
+ /* 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_device *udev)
+{
+ struct stub_device *sdev;
+ const char *udev_busid = dev_name(&udev->dev);
+ struct bus_id_priv *busid_priv;
+ int rc;
+
+ dev_dbg(&udev->dev, "Enter\n");
+
+ busid_priv = get_busid_priv(udev_busid);
+ if (!busid_priv) {
+ BUG();
+ return;
+ }
+
+ sdev = dev_get_drvdata(&udev->dev);
+
+ /* get stub_device */
+ if (!sdev) {
+ dev_err(&udev->dev, "could not get device");
+ return;
+ }
+
+ dev_set_drvdata(&udev->dev, NULL);
+
+ /*
+ * NOTE: rx/tx threads are invoked for each usb_device.
+ */
+ stub_remove_files(&udev->dev);
+
+ /* release port */
+ rc = usb_hub_release_port(udev->parent, udev->portnum,
+ (struct usb_dev_state *) udev);
+ if (rc) {
+ dev_dbg(&udev->dev, "unable to release port\n");
+ return;
+ }
+
+ /* If usb reset is called from event handler */
+ if (busid_priv->sdev->ud.eh == current)
+ return;
+
+ /* shutdown the current connection */
+ shutdown_busid(busid_priv);
+
+ usb_put_dev(sdev->udev);
+
+ /* 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);
+ }
+}
+
+#ifdef CONFIG_PM
+
+/* These functions need usb_port_suspend and usb_port_resume,
+ * which reside in drivers/usb/core/usb.h. Skip for now. */
+
+static int stub_suspend(struct usb_device *udev, pm_message_t message)
+{
+ dev_dbg(&udev->dev, "stub_suspend\n");
+
+ return 0;
+}
+
+static int stub_resume(struct usb_device *udev, pm_message_t message)
+{
+ dev_dbg(&udev->dev, "stub_resume\n");
+
+ return 0;
+}
+
+#endif /* CONFIG_PM */
+
+struct usb_device_driver stub_driver = {
+ .name = "usbip-host",
+ .probe = stub_probe,
+ .disconnect = stub_disconnect,
+#ifdef CONFIG_PM
+ .suspend = stub_suspend,
+ .resume = stub_resume,
+#endif
+ .supports_autosuspend = 0,
+};