212 lines · c
1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * Copyright (C) 2011 matt mooney <mfm@muteddisk.com>4 * 2005-2007 Takahiro Hirofuchi5 */6 7#include <libudev.h>8 9#include <errno.h>10#include <stdio.h>11#include <stdlib.h>12#include <string.h>13 14#include <getopt.h>15 16#include "usbip_common.h"17#include "utils.h"18#include "usbip.h"19#include "sysfs_utils.h"20 21enum unbind_status {22 UNBIND_ST_OK,23 UNBIND_ST_USBIP_HOST,24 UNBIND_ST_FAILED25};26 27static const char usbip_bind_usage_string[] =28 "usbip bind <args>\n"29 " -b, --busid=<busid> Bind " USBIP_HOST_DRV_NAME ".ko to device "30 "on <busid>\n";31 32void usbip_bind_usage(void)33{34 printf("usage: %s", usbip_bind_usage_string);35}36 37/* call at unbound state */38static int bind_usbip(char *busid)39{40 char attr_name[] = "bind";41 char bind_attr_path[SYSFS_PATH_MAX];42 int rc = -1;43 44 snprintf(bind_attr_path, sizeof(bind_attr_path), "%s/%s/%s/%s/%s/%s",45 SYSFS_MNT_PATH, SYSFS_BUS_NAME, SYSFS_BUS_TYPE,46 SYSFS_DRIVERS_NAME, USBIP_HOST_DRV_NAME, attr_name);47 48 rc = write_sysfs_attribute(bind_attr_path, busid, strlen(busid));49 if (rc < 0) {50 err("error binding device %s to driver: %s", busid,51 strerror(errno));52 return -1;53 }54 55 return 0;56}57 58/* buggy driver may cause dead lock */59static int unbind_other(char *busid)60{61 enum unbind_status status = UNBIND_ST_OK;62 63 char attr_name[] = "unbind";64 char unbind_attr_path[SYSFS_PATH_MAX];65 int rc = -1;66 67 struct udev *udev;68 struct udev_device *dev;69 const char *driver;70 const char *bDevClass;71 72 /* Create libudev context. */73 udev = udev_new();74 75 /* Get the device. */76 dev = udev_device_new_from_subsystem_sysname(udev, "usb", busid);77 if (!dev) {78 dbg("unable to find device with bus ID %s", busid);79 goto err_close_busid_dev;80 }81 82 /* Check what kind of device it is. */83 bDevClass = udev_device_get_sysattr_value(dev, "bDeviceClass");84 if (!bDevClass) {85 dbg("unable to get bDevClass device attribute");86 goto err_close_busid_dev;87 }88 89 if (!strncmp(bDevClass, "09", strlen(bDevClass))) {90 dbg("skip unbinding of hub");91 goto err_close_busid_dev;92 }93 94 /* Get the device driver. */95 driver = udev_device_get_driver(dev);96 if (!driver) {97 /* No driver bound to this device. */98 goto out;99 }100 101 if (!strncmp(USBIP_HOST_DRV_NAME, driver,102 strlen(USBIP_HOST_DRV_NAME))) {103 /* Already bound to usbip-host. */104 status = UNBIND_ST_USBIP_HOST;105 goto out;106 }107 108 /* Unbind device from driver. */109 snprintf(unbind_attr_path, sizeof(unbind_attr_path), "%s/%s/%s/%s/%s/%s",110 SYSFS_MNT_PATH, SYSFS_BUS_NAME, SYSFS_BUS_TYPE,111 SYSFS_DRIVERS_NAME, driver, attr_name);112 113 rc = write_sysfs_attribute(unbind_attr_path, busid, strlen(busid));114 if (rc < 0) {115 err("error unbinding device %s from driver", busid);116 goto err_close_busid_dev;117 }118 119 goto out;120 121err_close_busid_dev:122 status = UNBIND_ST_FAILED;123out:124 udev_device_unref(dev);125 udev_unref(udev);126 127 return status;128}129 130static int bind_device(char *busid)131{132 int rc;133 struct udev *udev;134 struct udev_device *dev;135 const char *devpath;136 137 /* Check whether the device with this bus ID exists. */138 udev = udev_new();139 dev = udev_device_new_from_subsystem_sysname(udev, "usb", busid);140 if (!dev) {141 err("device with the specified bus ID does not exist");142 return -1;143 }144 devpath = udev_device_get_devpath(dev);145 udev_unref(udev);146 147 /* If the device is already attached to vhci_hcd - bail out */148 if (strstr(devpath, USBIP_VHCI_DRV_NAME)) {149 err("bind loop detected: device: %s is attached to %s\n",150 devpath, USBIP_VHCI_DRV_NAME);151 return -1;152 }153 154 rc = unbind_other(busid);155 if (rc == UNBIND_ST_FAILED) {156 err("could not unbind driver from device on busid %s", busid);157 return -1;158 } else if (rc == UNBIND_ST_USBIP_HOST) {159 err("device on busid %s is already bound to %s", busid,160 USBIP_HOST_DRV_NAME);161 return -1;162 }163 164 rc = modify_match_busid(busid, 1);165 if (rc < 0) {166 err("unable to bind device on %s", busid);167 return -1;168 }169 170 rc = bind_usbip(busid);171 if (rc < 0) {172 err("could not bind device to %s", USBIP_HOST_DRV_NAME);173 modify_match_busid(busid, 0);174 return -1;175 }176 177 info("bind device on busid %s: complete", busid);178 179 return 0;180}181 182int usbip_bind(int argc, char *argv[])183{184 static const struct option opts[] = {185 { "busid", required_argument, NULL, 'b' },186 { NULL, 0, NULL, 0 }187 };188 189 int opt;190 int ret = -1;191 192 for (;;) {193 opt = getopt_long(argc, argv, "b:", opts, NULL);194 195 if (opt == -1)196 break;197 198 switch (opt) {199 case 'b':200 ret = bind_device(optarg);201 goto out;202 default:203 goto err_out;204 }205 }206 207err_out:208 usbip_bind_usage();209out:210 return ret;211}212