1 files changed, 498 insertions, 0 deletions

diff --git a/drivers/usb/usbip/stub_dev.c b/drivers/usb/usbip/stub_dev.c
new file mode 100644
index 000000000000..fac20e0434c0
--- /dev/null
+++ b/drivers/usb/usbip/stub_dev.c
@@ -0,0 +1,498 @@
+/*
+ * 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);
+        int err = 0;
+        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");
+                return rc;
+        }
+
+        err = stub_add_files(&udev->dev);
+        if (err) {
+                dev_err(&udev->dev, "stub_add_files for %s\n", udev_busid);
+                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 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);
+
+                /* 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,
+};