| // SPDX-License-Identifier: GPL-2.0+ |
| /* |
| * 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; |
| sdev->ud.sockfd = sockfd; |
| |
| 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 sockfd %d\n", ud->sockfd); |
| 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; |
| ud->sockfd = -1; |
| } |
| |
| /* 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, NULL); |
| 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 |
| * @udev: usb_device 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; |
| sdev->ud.sockfd = -1; |
| |
| 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 = 0; |
| |
| dev_dbg(&udev->dev, "Enter probe\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 |
| */ |
| rc = -ENODEV; |
| goto call_put_busid_priv; |
| } |
| |
| if (udev->descriptor.bDeviceClass == USB_CLASS_HUB) { |
| dev_dbg(&udev->dev, "%s is a usb hub device... skip!\n", |
| udev_busid); |
| rc = -ENODEV; |
| goto call_put_busid_priv; |
| } |
| |
| if (!strcmp(udev->bus->bus_name, "vhci_hcd")) { |
| dev_dbg(&udev->dev, |
| "%s is attached on vhci_hcd... skip!\n", |
| udev_busid); |
| |
| rc = -ENODEV; |
| goto call_put_busid_priv; |
| } |
| |
| /* ok, this is my device */ |
| sdev = stub_device_alloc(udev); |
| if (!sdev) { |
| rc = -ENOMEM; |
| goto call_put_busid_priv; |
| } |
| |
| 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; |
| |
| rc = 0; |
| goto call_put_busid_priv; |
| |
| 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); |
| |
| busid_priv->sdev = NULL; |
| stub_device_free(sdev); |
| |
| call_put_busid_priv: |
| put_busid_priv(busid_priv); |
| 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 disconnect\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"); |
| goto call_put_busid_priv; |
| } |
| |
| 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"); |
| goto call_put_busid_priv; |
| } |
| |
| /* If usb reset is called from event handler */ |
| if (usbip_in_eh(current)) |
| goto call_put_busid_priv; |
| |
| /* 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; |
| |
| call_put_busid_priv: |
| put_busid_priv(busid_priv); |
| } |
| |
| #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, |
| }; |