1 // SPDX-License-Identifier: GPL-2.0+
3 * Copyright (C) 2003-2008 Takahiro Hirofuchi
6 #include <linux/string.h>
7 #include <linux/module.h>
8 #include <linux/device.h>
10 #include "usbip_common.h"
13 #define DRIVER_AUTHOR "Takahiro Hirofuchi"
14 #define DRIVER_DESC "USB/IP Host Driver"
16 struct kmem_cache *stub_priv_cache;
19 * busid_tables defines matching busids that usbip can grab. A user can change
20 * dynamically what device is locally used and what device is exported to a
24 static struct bus_id_priv busid_table[MAX_BUSID];
25 static spinlock_t busid_table_lock;
27 static void init_busid_table(void)
32 * This also sets the bus_table[i].status to
33 * STUB_BUSID_OTHER, which is 0.
35 memset(busid_table, 0, sizeof(busid_table));
37 spin_lock_init(&busid_table_lock);
39 for (i = 0; i < MAX_BUSID; i++)
40 spin_lock_init(&busid_table[i].busid_lock);
44 * Find the index of the busid by name.
45 * Must be called with busid_table_lock held.
47 static int get_busid_idx(const char *busid)
52 for (i = 0; i < MAX_BUSID; i++) {
53 spin_lock(&busid_table[i].busid_lock);
54 if (busid_table[i].name[0])
55 if (!strncmp(busid_table[i].name, busid, BUSID_SIZE)) {
57 spin_unlock(&busid_table[i].busid_lock);
60 spin_unlock(&busid_table[i].busid_lock);
65 /* Returns holding busid_lock. Should call put_busid_priv() to unlock */
66 struct bus_id_priv *get_busid_priv(const char *busid)
69 struct bus_id_priv *bid = NULL;
71 spin_lock(&busid_table_lock);
72 idx = get_busid_idx(busid);
74 bid = &(busid_table[idx]);
75 /* get busid_lock before returning */
76 spin_lock(&bid->busid_lock);
78 spin_unlock(&busid_table_lock);
83 void put_busid_priv(struct bus_id_priv *bid)
86 spin_unlock(&bid->busid_lock);
89 static int add_match_busid(char *busid)
94 spin_lock(&busid_table_lock);
95 /* already registered? */
96 if (get_busid_idx(busid) >= 0) {
101 for (i = 0; i < MAX_BUSID; i++) {
102 spin_lock(&busid_table[i].busid_lock);
103 if (!busid_table[i].name[0]) {
104 strlcpy(busid_table[i].name, busid, BUSID_SIZE);
105 if ((busid_table[i].status != STUB_BUSID_ALLOC) &&
106 (busid_table[i].status != STUB_BUSID_REMOV))
107 busid_table[i].status = STUB_BUSID_ADDED;
109 spin_unlock(&busid_table[i].busid_lock);
112 spin_unlock(&busid_table[i].busid_lock);
116 spin_unlock(&busid_table_lock);
121 int del_match_busid(char *busid)
126 spin_lock(&busid_table_lock);
127 idx = get_busid_idx(busid);
134 spin_lock(&busid_table[idx].busid_lock);
136 if (busid_table[idx].status == STUB_BUSID_OTHER)
137 memset(busid_table[idx].name, 0, BUSID_SIZE);
139 if ((busid_table[idx].status != STUB_BUSID_OTHER) &&
140 (busid_table[idx].status != STUB_BUSID_ADDED))
141 busid_table[idx].status = STUB_BUSID_REMOV;
143 spin_unlock(&busid_table[idx].busid_lock);
145 spin_unlock(&busid_table_lock);
150 static ssize_t match_busid_show(struct device_driver *drv, char *buf)
155 spin_lock(&busid_table_lock);
156 for (i = 0; i < MAX_BUSID; i++) {
157 spin_lock(&busid_table[i].busid_lock);
158 if (busid_table[i].name[0])
159 out += sprintf(out, "%s ", busid_table[i].name);
160 spin_unlock(&busid_table[i].busid_lock);
162 spin_unlock(&busid_table_lock);
163 out += sprintf(out, "\n");
168 static ssize_t match_busid_store(struct device_driver *dev, const char *buf,
172 char busid[BUSID_SIZE];
177 /* busid needs to include \0 termination */
178 len = strlcpy(busid, buf + 4, BUSID_SIZE);
179 if (sizeof(busid) <= len)
182 if (!strncmp(buf, "add ", 4)) {
183 if (add_match_busid(busid) < 0)
186 pr_debug("add busid %s\n", busid);
190 if (!strncmp(buf, "del ", 4)) {
191 if (del_match_busid(busid) < 0)
194 pr_debug("del busid %s\n", busid);
200 static DRIVER_ATTR_RW(match_busid);
202 static int do_rebind(char *busid, struct bus_id_priv *busid_priv)
206 /* device_attach() callers should hold parent lock for USB */
207 if (busid_priv->udev->dev.parent)
208 device_lock(busid_priv->udev->dev.parent);
209 ret = device_attach(&busid_priv->udev->dev);
210 if (busid_priv->udev->dev.parent)
211 device_unlock(busid_priv->udev->dev.parent);
213 dev_err(&busid_priv->udev->dev, "rebind failed\n");
219 static void stub_device_rebind(void)
221 #if IS_MODULE(CONFIG_USBIP_HOST)
222 struct bus_id_priv *busid_priv;
225 /* update status to STUB_BUSID_OTHER so probe ignores the device */
226 spin_lock(&busid_table_lock);
227 for (i = 0; i < MAX_BUSID; i++) {
228 if (busid_table[i].name[0] &&
229 busid_table[i].shutdown_busid) {
230 busid_priv = &(busid_table[i]);
231 busid_priv->status = STUB_BUSID_OTHER;
234 spin_unlock(&busid_table_lock);
236 /* now run rebind - no need to hold locks. driver files are removed */
237 for (i = 0; i < MAX_BUSID; i++) {
238 if (busid_table[i].name[0] &&
239 busid_table[i].shutdown_busid) {
240 busid_priv = &(busid_table[i]);
241 do_rebind(busid_table[i].name, busid_priv);
247 static ssize_t rebind_store(struct device_driver *dev, const char *buf,
252 struct bus_id_priv *bid;
254 /* buf length should be less that BUSID_SIZE */
255 len = strnlen(buf, BUSID_SIZE);
257 if (!(len < BUSID_SIZE))
260 bid = get_busid_priv(buf);
264 /* mark the device for deletion so probe ignores it during rescan */
265 bid->status = STUB_BUSID_OTHER;
266 /* release the busid lock */
269 ret = do_rebind((char *) buf, bid);
273 /* delete device from busid_table */
274 del_match_busid((char *) buf);
279 static DRIVER_ATTR_WO(rebind);
281 static struct stub_priv *stub_priv_pop_from_listhead(struct list_head *listhead)
283 struct stub_priv *priv, *tmp;
285 list_for_each_entry_safe(priv, tmp, listhead, list) {
286 list_del(&priv->list);
293 static struct stub_priv *stub_priv_pop(struct stub_device *sdev)
296 struct stub_priv *priv;
298 spin_lock_irqsave(&sdev->priv_lock, flags);
300 priv = stub_priv_pop_from_listhead(&sdev->priv_init);
304 priv = stub_priv_pop_from_listhead(&sdev->priv_tx);
308 priv = stub_priv_pop_from_listhead(&sdev->priv_free);
311 spin_unlock_irqrestore(&sdev->priv_lock, flags);
316 void stub_device_cleanup_urbs(struct stub_device *sdev)
318 struct stub_priv *priv;
321 dev_dbg(&sdev->udev->dev, "Stub device cleaning up urbs\n");
323 while ((priv = stub_priv_pop(sdev))) {
325 dev_dbg(&sdev->udev->dev, "free urb seqnum %lu\n",
329 kmem_cache_free(stub_priv_cache, priv);
331 kfree(urb->transfer_buffer);
332 urb->transfer_buffer = NULL;
334 kfree(urb->setup_packet);
335 urb->setup_packet = NULL;
341 static int __init usbip_host_init(void)
347 stub_priv_cache = KMEM_CACHE(stub_priv, SLAB_HWCACHE_ALIGN);
348 if (!stub_priv_cache) {
349 pr_err("kmem_cache_create failed\n");
353 ret = usb_register_device_driver(&stub_driver, THIS_MODULE);
355 pr_err("usb_register failed %d\n", ret);
356 goto err_usb_register;
359 ret = driver_create_file(&stub_driver.drvwrap.driver,
360 &driver_attr_match_busid);
362 pr_err("driver_create_file failed\n");
363 goto err_create_file;
366 ret = driver_create_file(&stub_driver.drvwrap.driver,
367 &driver_attr_rebind);
369 pr_err("driver_create_file failed\n");
370 goto err_create_file;
376 usb_deregister_device_driver(&stub_driver);
378 kmem_cache_destroy(stub_priv_cache);
382 static void __exit usbip_host_exit(void)
384 driver_remove_file(&stub_driver.drvwrap.driver,
385 &driver_attr_match_busid);
387 driver_remove_file(&stub_driver.drvwrap.driver,
388 &driver_attr_rebind);
391 * deregister() calls stub_disconnect() for all devices. Device
392 * specific data is cleared in stub_disconnect().
394 usb_deregister_device_driver(&stub_driver);
396 /* initiate scan to attach devices */
397 stub_device_rebind();
399 kmem_cache_destroy(stub_priv_cache);
402 module_init(usbip_host_init);
403 module_exit(usbip_host_exit);
405 MODULE_AUTHOR(DRIVER_AUTHOR);
406 MODULE_DESCRIPTION(DRIVER_DESC);
407 MODULE_LICENSE("GPL");