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>
9 #include <linux/scatterlist.h>
11 #include "usbip_common.h"
14 #define DRIVER_AUTHOR "Takahiro Hirofuchi"
15 #define DRIVER_DESC "USB/IP Host Driver"
17 struct kmem_cache *stub_priv_cache;
20 * busid_tables defines matching busids that usbip can grab. A user can change
21 * dynamically what device is locally used and what device is exported to a
25 static struct bus_id_priv busid_table[MAX_BUSID];
26 static DEFINE_SPINLOCK(busid_table_lock);
28 static void init_busid_table(void)
33 * This also sets the bus_table[i].status to
34 * STUB_BUSID_OTHER, which is 0.
36 memset(busid_table, 0, sizeof(busid_table));
38 for (i = 0; i < MAX_BUSID; i++)
39 spin_lock_init(&busid_table[i].busid_lock);
43 * Find the index of the busid by name.
44 * Must be called with busid_table_lock held.
46 static int get_busid_idx(const char *busid)
51 for (i = 0; i < MAX_BUSID; i++) {
52 spin_lock(&busid_table[i].busid_lock);
53 if (busid_table[i].name[0])
54 if (!strncmp(busid_table[i].name, busid, BUSID_SIZE)) {
56 spin_unlock(&busid_table[i].busid_lock);
59 spin_unlock(&busid_table[i].busid_lock);
64 /* Returns holding busid_lock. Should call put_busid_priv() to unlock */
65 struct bus_id_priv *get_busid_priv(const char *busid)
68 struct bus_id_priv *bid = NULL;
70 spin_lock(&busid_table_lock);
71 idx = get_busid_idx(busid);
73 bid = &(busid_table[idx]);
74 /* get busid_lock before returning */
75 spin_lock(&bid->busid_lock);
77 spin_unlock(&busid_table_lock);
82 void put_busid_priv(struct bus_id_priv *bid)
85 spin_unlock(&bid->busid_lock);
88 static int add_match_busid(char *busid)
93 spin_lock(&busid_table_lock);
94 /* already registered? */
95 if (get_busid_idx(busid) >= 0) {
100 for (i = 0; i < MAX_BUSID; i++) {
101 spin_lock(&busid_table[i].busid_lock);
102 if (!busid_table[i].name[0]) {
103 strscpy(busid_table[i].name, busid, BUSID_SIZE);
104 if ((busid_table[i].status != STUB_BUSID_ALLOC) &&
105 (busid_table[i].status != STUB_BUSID_REMOV))
106 busid_table[i].status = STUB_BUSID_ADDED;
108 spin_unlock(&busid_table[i].busid_lock);
111 spin_unlock(&busid_table[i].busid_lock);
115 spin_unlock(&busid_table_lock);
120 int del_match_busid(char *busid)
125 spin_lock(&busid_table_lock);
126 idx = get_busid_idx(busid);
133 spin_lock(&busid_table[idx].busid_lock);
135 if (busid_table[idx].status == STUB_BUSID_OTHER)
136 memset(busid_table[idx].name, 0, BUSID_SIZE);
138 if ((busid_table[idx].status != STUB_BUSID_OTHER) &&
139 (busid_table[idx].status != STUB_BUSID_ADDED))
140 busid_table[idx].status = STUB_BUSID_REMOV;
142 spin_unlock(&busid_table[idx].busid_lock);
144 spin_unlock(&busid_table_lock);
149 static ssize_t match_busid_show(struct device_driver *drv, char *buf)
154 spin_lock(&busid_table_lock);
155 for (i = 0; i < MAX_BUSID; i++) {
156 spin_lock(&busid_table[i].busid_lock);
157 if (busid_table[i].name[0])
158 out += sprintf(out, "%s ", busid_table[i].name);
159 spin_unlock(&busid_table[i].busid_lock);
161 spin_unlock(&busid_table_lock);
162 out += sprintf(out, "\n");
167 static ssize_t match_busid_store(struct device_driver *dev, const char *buf,
170 char busid[BUSID_SIZE];
175 /* busid needs to include \0 termination */
176 if (strscpy(busid, buf + 4, BUSID_SIZE) < 0)
179 if (!strncmp(buf, "add ", 4)) {
180 if (add_match_busid(busid) < 0)
183 pr_debug("add busid %s\n", busid);
187 if (!strncmp(buf, "del ", 4)) {
188 if (del_match_busid(busid) < 0)
191 pr_debug("del busid %s\n", busid);
197 static DRIVER_ATTR_RW(match_busid);
199 static int do_rebind(char *busid, struct bus_id_priv *busid_priv)
203 /* device_attach() callers should hold parent lock for USB */
204 if (busid_priv->udev->dev.parent)
205 device_lock(busid_priv->udev->dev.parent);
206 ret = device_attach(&busid_priv->udev->dev);
207 if (busid_priv->udev->dev.parent)
208 device_unlock(busid_priv->udev->dev.parent);
210 dev_err(&busid_priv->udev->dev, "rebind failed\n");
214 static void stub_device_rebind(void)
216 #if IS_MODULE(CONFIG_USBIP_HOST)
217 struct bus_id_priv *busid_priv;
220 /* update status to STUB_BUSID_OTHER so probe ignores the device */
221 spin_lock(&busid_table_lock);
222 for (i = 0; i < MAX_BUSID; i++) {
223 if (busid_table[i].name[0] &&
224 busid_table[i].shutdown_busid) {
225 busid_priv = &(busid_table[i]);
226 busid_priv->status = STUB_BUSID_OTHER;
229 spin_unlock(&busid_table_lock);
231 /* now run rebind - no need to hold locks. driver files are removed */
232 for (i = 0; i < MAX_BUSID; i++) {
233 if (busid_table[i].name[0] &&
234 busid_table[i].shutdown_busid) {
235 busid_priv = &(busid_table[i]);
236 do_rebind(busid_table[i].name, busid_priv);
242 static ssize_t rebind_store(struct device_driver *dev, const char *buf,
247 struct bus_id_priv *bid;
249 /* buf length should be less that BUSID_SIZE */
250 len = strnlen(buf, BUSID_SIZE);
252 if (!(len < BUSID_SIZE))
255 bid = get_busid_priv(buf);
259 /* mark the device for deletion so probe ignores it during rescan */
260 bid->status = STUB_BUSID_OTHER;
261 /* release the busid lock */
264 ret = do_rebind((char *) buf, bid);
268 /* delete device from busid_table */
269 del_match_busid((char *) buf);
274 static DRIVER_ATTR_WO(rebind);
276 static struct stub_priv *stub_priv_pop_from_listhead(struct list_head *listhead)
278 struct stub_priv *priv, *tmp;
280 list_for_each_entry_safe(priv, tmp, listhead, list) {
281 list_del_init(&priv->list);
288 void stub_free_priv_and_urb(struct stub_priv *priv)
293 for (i = 0; i < priv->num_urbs; i++) {
299 kfree(urb->setup_packet);
300 urb->setup_packet = NULL;
303 if (urb->transfer_buffer && !priv->sgl) {
304 kfree(urb->transfer_buffer);
305 urb->transfer_buffer = NULL;
316 if (!list_empty(&priv->list))
317 list_del(&priv->list);
321 kmem_cache_free(stub_priv_cache, priv);
324 static struct stub_priv *stub_priv_pop(struct stub_device *sdev)
327 struct stub_priv *priv;
329 spin_lock_irqsave(&sdev->priv_lock, flags);
331 priv = stub_priv_pop_from_listhead(&sdev->priv_init);
335 priv = stub_priv_pop_from_listhead(&sdev->priv_tx);
339 priv = stub_priv_pop_from_listhead(&sdev->priv_free);
342 spin_unlock_irqrestore(&sdev->priv_lock, flags);
347 void stub_device_cleanup_urbs(struct stub_device *sdev)
349 struct stub_priv *priv;
352 dev_dbg(&sdev->udev->dev, "Stub device cleaning up urbs\n");
354 while ((priv = stub_priv_pop(sdev))) {
355 for (i = 0; i < priv->num_urbs; i++)
356 usb_kill_urb(priv->urbs[i]);
358 stub_free_priv_and_urb(priv);
362 static int __init usbip_host_init(void)
368 stub_priv_cache = KMEM_CACHE(stub_priv, SLAB_HWCACHE_ALIGN);
369 if (!stub_priv_cache) {
370 pr_err("kmem_cache_create failed\n");
374 ret = usb_register_device_driver(&stub_driver, THIS_MODULE);
376 pr_err("usb_register failed %d\n", ret);
377 goto err_usb_register;
380 ret = driver_create_file(&stub_driver.drvwrap.driver,
381 &driver_attr_match_busid);
383 pr_err("driver_create_file failed\n");
384 goto err_create_file;
387 ret = driver_create_file(&stub_driver.drvwrap.driver,
388 &driver_attr_rebind);
390 pr_err("driver_create_file failed\n");
391 goto err_create_file;
397 usb_deregister_device_driver(&stub_driver);
399 kmem_cache_destroy(stub_priv_cache);
403 static void __exit usbip_host_exit(void)
405 driver_remove_file(&stub_driver.drvwrap.driver,
406 &driver_attr_match_busid);
408 driver_remove_file(&stub_driver.drvwrap.driver,
409 &driver_attr_rebind);
412 * deregister() calls stub_disconnect() for all devices. Device
413 * specific data is cleared in stub_disconnect().
415 usb_deregister_device_driver(&stub_driver);
417 /* initiate scan to attach devices */
418 stub_device_rebind();
420 kmem_cache_destroy(stub_priv_cache);
423 module_init(usbip_host_init);
424 module_exit(usbip_host_exit);
426 MODULE_AUTHOR(DRIVER_AUTHOR);
427 MODULE_DESCRIPTION(DRIVER_DESC);
428 MODULE_LICENSE("GPL");