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authorLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
committerLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
commit5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch)
treecc5c2d0a898769fd59549594fedb3ee6f84e59a0 /drivers/usb/usbip/stub_dev.c
downloadlinux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz
linux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.zip
Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted
Pull networking updates from Jakub Kicinski: "Core: - Add dedicated kmem_cache for typical/small skb->head, avoid having to access struct page at kfree time, and improve memory use. - Introduce sysctl to set default RPS configuration for new netdevs. - Define Netlink protocol specification format which can be used to describe messages used by each family and auto-generate parsers. Add tools for generating kernel data structures and uAPI headers. - Expose all net/core sysctls inside netns. - Remove 4s sleep in netpoll if carrier is instantly detected on boot. - Add configurable limit of MDB entries per port, and port-vlan. - Continue populating drop reasons throughout the stack. - Retire a handful of legacy Qdiscs and classifiers. Protocols: - Support IPv4 big TCP (TSO frames larger than 64kB). - Add IP_LOCAL_PORT_RANGE socket option, to control local port range on socket by socket basis. - Track and report in procfs number of MPTCP sockets used. - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path manager. - IPv6: don't check net.ipv6.route.max_size and rely on garbage collection to free memory (similarly to IPv4). - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986). - ICMP: add per-rate limit counters. - Add support for user scanning requests in ieee802154. - Remove static WEP support. - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate reporting. - WiFi 7 EHT channel puncturing support (client & AP). BPF: - Add a rbtree data structure following the "next-gen data structure" precedent set by recently added linked list, that is, by using kfunc + kptr instead of adding a new BPF map type. - Expose XDP hints via kfuncs with initial support for RX hash and timestamp metadata. - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to better support decap on GRE tunnel devices not operating in collect metadata. - Improve x86 JIT's codegen for PROBE_MEM runtime error checks. - Remove the need for trace_printk_lock for bpf_trace_printk and bpf_trace_vprintk helpers. - Extend libbpf's bpf_tracing.h support for tracing arguments of kprobes/uprobes and syscall as a special case. - Significantly reduce the search time for module symbols by livepatch and BPF. - Enable cpumasks to be used as kptrs, which is useful for tracing programs tracking which tasks end up running on which CPUs in different time intervals. - Add support for BPF trampoline on s390x and riscv64. - Add capability to export the XDP features supported by the NIC. - Add __bpf_kfunc tag for marking kernel functions as kfuncs. - Add cgroup.memory=nobpf kernel parameter option to disable BPF memory accounting for container environments. Netfilter: - Remove the CLUSTERIP target. It has been marked as obsolete for years, and we still have WARN splats wrt races of the out-of-band /proc interface installed by this target. - Add 'destroy' commands to nf_tables. They are identical to the existing 'delete' commands, but do not return an error if the referenced object (set, chain, rule...) did not exist. Driver API: - Improve cpumask_local_spread() locality to help NICs set the right IRQ affinity on AMD platforms. - Separate C22 and C45 MDIO bus transactions more clearly. - Introduce new DCB table to control DSCP rewrite on egress. - Support configuration of Physical Layer Collision Avoidance (PLCA) Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of shared medium Ethernet. - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing preemption of low priority frames by high priority frames. - Add support for controlling MACSec offload using netlink SET. - Rework devlink instance refcounts to allow registration and de-registration under the instance lock. Split the code into multiple files, drop some of the unnecessarily granular locks and factor out common parts of netlink operation handling. - Add TX frame aggregation parameters (for USB drivers). - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning messages with notifications for debug. - Allow offloading of UDP NEW connections via act_ct. - Add support for per action HW stats in TC. - Support hardware miss to TC action (continue processing in SW from a specific point in the action chain). - Warn if old Wireless Extension user space interface is used with modern cfg80211/mac80211 drivers. Do not support Wireless Extensions for Wi-Fi 7 devices at all. Everyone should switch to using nl80211 interface instead. - Improve the CAN bit timing configuration. Use extack to return error messages directly to user space, update the SJW handling, including the definition of a new default value that will benefit CAN-FD controllers, by increasing their oscillator tolerance. New hardware / drivers: - Ethernet: - nVidia BlueField-3 support (control traffic driver) - Ethernet support for imx93 SoCs - Motorcomm yt8531 gigabit Ethernet PHY - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA) - Microchip LAN8841 PHY (incl. cable diagnostics and PTP) - Amlogic gxl MDIO mux - WiFi: - RealTek RTL8188EU (rtl8xxxu) - Qualcomm Wi-Fi 7 devices (ath12k) - CAN: - Renesas R-Car V4H Drivers: - Bluetooth: - Set Per Platform Antenna Gain (PPAG) for Intel controllers. - Ethernet NICs: - Intel (1G, igc): - support TSN / Qbv / packet scheduling features of i226 model - Intel (100G, ice): - use GNSS subsystem instead of TTY - multi-buffer XDP support - extend support for GPIO pins to E823 devices - nVidia/Mellanox: - update the shared buffer configuration on PFC commands - implement PTP adjphase function for HW offset control - TC support for Geneve and GRE with VF tunnel offload - more efficient crypto key management method - multi-port eswitch support - Netronome/Corigine: - add DCB IEEE support - support IPsec offloading for NFP3800 - Freescale/NXP (enetc): - support XDP_REDIRECT for XDP non-linear buffers - improve reconfig, avoid link flap and waiting for idle - support MAC Merge layer - Other NICs: - sfc/ef100: add basic devlink support for ef100 - ionic: rx_push mode operation (writing descriptors via MMIO) - bnxt: use the auxiliary bus abstraction for RDMA - r8169: disable ASPM and reset bus in case of tx timeout - cpsw: support QSGMII mode for J721e CPSW9G - cpts: support pulse-per-second output - ngbe: add an mdio bus driver - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing - r8152: handle devices with FW with NCM support - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation - virtio-net: support multi buffer XDP - virtio/vsock: replace virtio_vsock_pkt with sk_buff - tsnep: XDP support - Ethernet high-speed switches: - nVidia/Mellanox (mlxsw): - add support for latency TLV (in FW control messages) - Microchip (sparx5): - separate explicit and implicit traffic forwarding rules, make the implicit rules always active - add support for egress DSCP rewrite - IS0 VCAP support (Ingress Classification) - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS etc.) - ES2 VCAP support (Egress Access Control) - support for Per-Stream Filtering and Policing (802.1Q, 8.6.5.1) - Ethernet embedded switches: - Marvell (mv88e6xxx): - add MAB (port auth) offload support - enable PTP receive for mv88e6390 - NXP (ocelot): - support MAC Merge layer - support for the the vsc7512 internal copper phys - Microchip: - lan9303: convert to PHYLINK - lan966x: support TC flower filter statistics - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x - lan937x: support Credit Based Shaper configuration - ksz9477: support Energy Efficient Ethernet - other: - qca8k: convert to regmap read/write API, use bulk operations - rswitch: Improve TX timestamp accuracy - Intel WiFi (iwlwifi): - EHT (Wi-Fi 7) rate reporting - STEP equalizer support: transfer some STEP (connection to radio on platforms with integrated wifi) related parameters from the BIOS to the firmware. - Qualcomm 802.11ax WiFi (ath11k): - IPQ5018 support - Fine Timing Measurement (FTM) responder role support - channel 177 support - MediaTek WiFi (mt76): - per-PHY LED support - mt7996: EHT (Wi-Fi 7) support - Wireless Ethernet Dispatch (WED) reset support - switch to using page pool allocator - RealTek WiFi (rtw89): - support new version of Bluetooth co-existance - Mobile: - rmnet: support TX aggregation" * tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits) page_pool: add a comment explaining the fragment counter usage net: ethtool: fix __ethtool_dev_mm_supported() implementation ethtool: pse-pd: Fix double word in comments xsk: add linux/vmalloc.h to xsk.c sefltests: netdevsim: wait for devlink instance after netns removal selftest: fib_tests: Always cleanup before exit net/mlx5e: Align IPsec ASO result memory to be as required by hardware net/mlx5e: TC, Set CT miss to the specific ct action instance net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG net/mlx5: Refactor tc miss handling to a single function net/mlx5: Kconfig: Make tc offload depend on tc skb extension net/sched: flower: Support hardware miss to tc action net/sched: flower: Move filter handle initialization earlier net/sched: cls_api: Support hardware miss to tc action net/sched: Rename user cookie and act cookie sfc: fix builds without CONFIG_RTC_LIB sfc: clean up some inconsistent indentings net/mlx4_en: Introduce flexible array to silence overflow warning net: lan966x: Fix possible deadlock inside PTP net/ulp: Remove redundant ->clone() test in inet_clone_ulp(). ...
Diffstat (limited to 'drivers/usb/usbip/stub_dev.c')
-rw-r--r--drivers/usb/usbip/stub_dev.c532
1 files changed, 532 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..9c6954aad
--- /dev/null
+++ b/drivers/usb/usbip/stub_dev.c
@@ -0,0 +1,532 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2003-2008 Takahiro Hirofuchi
+ */
+
+#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 sysfs_emit(buf, "%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 usbip_sockfd_store(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;
+ struct task_struct *tcp_rx = NULL;
+ struct task_struct *tcp_tx = NULL;
+
+ 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");
+
+ mutex_lock(&sdev->ud.sysfs_lock);
+ 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) {
+ dev_err(dev, "failed to lookup sock");
+ goto err;
+ }
+
+ if (socket->type != SOCK_STREAM) {
+ dev_err(dev, "Expecting SOCK_STREAM - found %d",
+ socket->type);
+ goto sock_err;
+ }
+
+ /* unlock and create threads and get tasks */
+ spin_unlock_irq(&sdev->ud.lock);
+ tcp_rx = kthread_create(stub_rx_loop, &sdev->ud, "stub_rx");
+ if (IS_ERR(tcp_rx)) {
+ sockfd_put(socket);
+ goto unlock_mutex;
+ }
+ tcp_tx = kthread_create(stub_tx_loop, &sdev->ud, "stub_tx");
+ if (IS_ERR(tcp_tx)) {
+ kthread_stop(tcp_rx);
+ sockfd_put(socket);
+ goto unlock_mutex;
+ }
+
+ /* get task structs now */
+ get_task_struct(tcp_rx);
+ get_task_struct(tcp_tx);
+
+ /* lock and update sdev->ud state */
+ spin_lock_irq(&sdev->ud.lock);
+ sdev->ud.tcp_socket = socket;
+ sdev->ud.sockfd = sockfd;
+ sdev->ud.tcp_rx = tcp_rx;
+ sdev->ud.tcp_tx = tcp_tx;
+ sdev->ud.status = SDEV_ST_USED;
+ spin_unlock_irq(&sdev->ud.lock);
+
+ wake_up_process(sdev->ud.tcp_rx);
+ wake_up_process(sdev->ud.tcp_tx);
+
+ mutex_unlock(&sdev->ud.sysfs_lock);
+
+ } else {
+ dev_info(dev, "stub down\n");
+
+ mutex_lock(&sdev->ud.sysfs_lock);
+
+ 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);
+ mutex_unlock(&sdev->ud.sysfs_lock);
+ }
+
+ return count;
+
+sock_err:
+ sockfd_put(socket);
+err:
+ spin_unlock_irq(&sdev->ud.lock);
+unlock_mutex:
+ mutex_unlock(&sdev->ud.sysfs_lock);
+ return -EINVAL;
+}
+static DEVICE_ATTR_WO(usbip_sockfd);
+
+static struct attribute *usbip_attrs[] = {
+ &dev_attr_usbip_status.attr,
+ &dev_attr_usbip_sockfd.attr,
+ &dev_attr_usbip_debug.attr,
+ NULL,
+};
+ATTRIBUTE_GROUPS(usbip);
+
+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);
+ mutex_init(&sdev->ud.sysfs_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;
+ char save_status;
+
+ dev_dbg(&udev->dev, "Enter probe\n");
+
+ /* Not sure if this is our device. Allocate here to avoid
+ * calling alloc while holding busid_table lock.
+ */
+ sdev = stub_device_alloc(udev);
+ if (!sdev)
+ return -ENOMEM;
+
+ /* 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;
+ if (!busid_priv)
+ goto sdev_free;
+
+ 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;
+ }
+
+
+ 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;
+
+ save_status = busid_priv->status;
+ busid_priv->status = STUB_BUSID_ALLOC;
+
+ /* release the busid_lock */
+ put_busid_priv(busid_priv);
+
+ /*
+ * 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;
+ }
+
+ return 0;
+
+err_port:
+ dev_set_drvdata(&udev->dev, NULL);
+
+ /* we already have busid_priv, just lock busid_lock */
+ spin_lock(&busid_priv->busid_lock);
+ busid_priv->sdev = NULL;
+ busid_priv->status = save_status;
+ spin_unlock(&busid_priv->busid_lock);
+ /* lock is released - go to free */
+ goto sdev_free;
+
+call_put_busid_priv:
+ /* release the busid_lock */
+ put_busid_priv(busid_priv);
+
+sdev_free:
+ usb_put_dev(udev);
+ stub_device_free(sdev);
+
+ return rc;
+}
+
+static void shutdown_busid(struct bus_id_priv *busid_priv)
+{
+ 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");
+ /* release busid_lock */
+ put_busid_priv(busid_priv);
+ return;
+ }
+
+ dev_set_drvdata(&udev->dev, NULL);
+
+ /* release busid_lock before call to remove device files */
+ put_busid_priv(busid_priv);
+
+ /*
+ * NOTE: rx/tx threads are invoked for each usb_device.
+ */
+
+ /* 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 (usbip_in_eh(current))
+ return;
+
+ /* we already have busid_priv, just lock busid_lock */
+ spin_lock(&busid_priv->busid_lock);
+ if (!busid_priv->shutdown_busid)
+ busid_priv->shutdown_busid = 1;
+ /* release busid_lock */
+ spin_unlock(&busid_priv->busid_lock);
+
+ /* shutdown the current connection */
+ shutdown_busid(busid_priv);
+
+ usb_put_dev(sdev->udev);
+
+ /* we already have busid_priv, just lock busid_lock */
+ spin_lock(&busid_priv->busid_lock);
+ /* free sdev */
+ busid_priv->sdev = NULL;
+ stub_device_free(sdev);
+
+ if (busid_priv->status == STUB_BUSID_ALLOC)
+ busid_priv->status = STUB_BUSID_ADDED;
+ /* release busid_lock */
+ spin_unlock(&busid_priv->busid_lock);
+ return;
+}
+
+#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,
+ .dev_groups = usbip_groups,
+};