1 /*
2 * Copyright (C) 2003-2008 Takahiro Hirofuchi
3 *
4 * This is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
8 *
9 * This is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
17 * USA.
18 */
19
20 #include <linux/string.h>
21 #include <linux/module.h>
22 #include <linux/device.h>
23
24 #include "usbip_common.h"
25 #include "stub.h"
26
27 #define DRIVER_AUTHOR "Takahiro Hirofuchi"
28 #define DRIVER_DESC "USB/IP Host Driver"
29
30 struct kmem_cache *stub_priv_cache;
31 /*
32 * busid_tables defines matching busids that usbip can grab. A user can change
33 * dynamically what device is locally used and what device is exported to a
34 * remote host.
35 */
36 #define MAX_BUSID 16
37 static struct bus_id_priv busid_table[MAX_BUSID];
38 static spinlock_t busid_table_lock;
39
init_busid_table(void)40 static void init_busid_table(void)
41 {
42 /*
43 * This also sets the bus_table[i].status to
44 * STUB_BUSID_OTHER, which is 0.
45 */
46 memset(busid_table, 0, sizeof(busid_table));
47
48 spin_lock_init(&busid_table_lock);
49 }
50
51 /*
52 * Find the index of the busid by name.
53 * Must be called with busid_table_lock held.
54 */
get_busid_idx(const char * busid)55 static int get_busid_idx(const char *busid)
56 {
57 int i;
58 int idx = -1;
59
60 for (i = 0; i < MAX_BUSID; i++)
61 if (busid_table[i].name[0])
62 if (!strncmp(busid_table[i].name, busid, BUSID_SIZE)) {
63 idx = i;
64 break;
65 }
66 return idx;
67 }
68
get_busid_priv(const char * busid)69 struct bus_id_priv *get_busid_priv(const char *busid)
70 {
71 int idx;
72 struct bus_id_priv *bid = NULL;
73
74 spin_lock(&busid_table_lock);
75 idx = get_busid_idx(busid);
76 if (idx >= 0)
77 bid = &(busid_table[idx]);
78 spin_unlock(&busid_table_lock);
79
80 return bid;
81 }
82
add_match_busid(char * busid)83 static int add_match_busid(char *busid)
84 {
85 int i;
86 int ret = -1;
87
88 spin_lock(&busid_table_lock);
89 /* already registered? */
90 if (get_busid_idx(busid) >= 0) {
91 ret = 0;
92 goto out;
93 }
94
95 for (i = 0; i < MAX_BUSID; i++)
96 if (!busid_table[i].name[0]) {
97 strlcpy(busid_table[i].name, busid, BUSID_SIZE);
98 if ((busid_table[i].status != STUB_BUSID_ALLOC) &&
99 (busid_table[i].status != STUB_BUSID_REMOV))
100 busid_table[i].status = STUB_BUSID_ADDED;
101 ret = 0;
102 break;
103 }
104
105 out:
106 spin_unlock(&busid_table_lock);
107
108 return ret;
109 }
110
del_match_busid(char * busid)111 int del_match_busid(char *busid)
112 {
113 int idx;
114 int ret = -1;
115
116 spin_lock(&busid_table_lock);
117 idx = get_busid_idx(busid);
118 if (idx < 0)
119 goto out;
120
121 /* found */
122 ret = 0;
123
124 if (busid_table[idx].status == STUB_BUSID_OTHER)
125 memset(busid_table[idx].name, 0, BUSID_SIZE);
126
127 if ((busid_table[idx].status != STUB_BUSID_OTHER) &&
128 (busid_table[idx].status != STUB_BUSID_ADDED))
129 busid_table[idx].status = STUB_BUSID_REMOV;
130
131 out:
132 spin_unlock(&busid_table_lock);
133
134 return ret;
135 }
136
show_match_busid(struct device_driver * drv,char * buf)137 static ssize_t show_match_busid(struct device_driver *drv, char *buf)
138 {
139 int i;
140 char *out = buf;
141
142 spin_lock(&busid_table_lock);
143 for (i = 0; i < MAX_BUSID; i++)
144 if (busid_table[i].name[0])
145 out += sprintf(out, "%s ", busid_table[i].name);
146 spin_unlock(&busid_table_lock);
147 out += sprintf(out, "\n");
148
149 return out - buf;
150 }
151
store_match_busid(struct device_driver * dev,const char * buf,size_t count)152 static ssize_t store_match_busid(struct device_driver *dev, const char *buf,
153 size_t count)
154 {
155 int len;
156 char busid[BUSID_SIZE];
157
158 if (count < 5)
159 return -EINVAL;
160
161 /* busid needs to include \0 termination */
162 len = strlcpy(busid, buf + 4, BUSID_SIZE);
163 if (sizeof(busid) <= len)
164 return -EINVAL;
165
166 if (!strncmp(buf, "add ", 4)) {
167 if (add_match_busid(busid) < 0)
168 return -ENOMEM;
169
170 pr_debug("add busid %s\n", busid);
171 return count;
172 }
173
174 if (!strncmp(buf, "del ", 4)) {
175 if (del_match_busid(busid) < 0)
176 return -ENODEV;
177
178 pr_debug("del busid %s\n", busid);
179 return count;
180 }
181
182 return -EINVAL;
183 }
184 static DRIVER_ATTR(match_busid, S_IRUSR | S_IWUSR, show_match_busid,
185 store_match_busid);
186
rebind_store(struct device_driver * dev,const char * buf,size_t count)187 static ssize_t rebind_store(struct device_driver *dev, const char *buf,
188 size_t count)
189 {
190 int ret;
191 int len;
192 struct bus_id_priv *bid;
193
194 /* buf length should be less that BUSID_SIZE */
195 len = strnlen(buf, BUSID_SIZE);
196
197 if (!(len < BUSID_SIZE))
198 return -EINVAL;
199
200 bid = get_busid_priv(buf);
201 if (!bid)
202 return -ENODEV;
203
204 ret = device_attach(&bid->udev->dev);
205 if (ret < 0) {
206 dev_err(&bid->udev->dev, "rebind failed\n");
207 return ret;
208 }
209
210 return count;
211 }
212
213 static DRIVER_ATTR_WO(rebind);
214
stub_priv_pop_from_listhead(struct list_head * listhead)215 static struct stub_priv *stub_priv_pop_from_listhead(struct list_head *listhead)
216 {
217 struct stub_priv *priv, *tmp;
218
219 list_for_each_entry_safe(priv, tmp, listhead, list) {
220 list_del(&priv->list);
221 return priv;
222 }
223
224 return NULL;
225 }
226
stub_priv_pop(struct stub_device * sdev)227 static struct stub_priv *stub_priv_pop(struct stub_device *sdev)
228 {
229 unsigned long flags;
230 struct stub_priv *priv;
231
232 spin_lock_irqsave(&sdev->priv_lock, flags);
233
234 priv = stub_priv_pop_from_listhead(&sdev->priv_init);
235 if (priv)
236 goto done;
237
238 priv = stub_priv_pop_from_listhead(&sdev->priv_tx);
239 if (priv)
240 goto done;
241
242 priv = stub_priv_pop_from_listhead(&sdev->priv_free);
243
244 done:
245 spin_unlock_irqrestore(&sdev->priv_lock, flags);
246
247 return priv;
248 }
249
stub_device_cleanup_urbs(struct stub_device * sdev)250 void stub_device_cleanup_urbs(struct stub_device *sdev)
251 {
252 struct stub_priv *priv;
253 struct urb *urb;
254
255 dev_dbg(&sdev->udev->dev, "Stub device cleaning up urbs\n");
256
257 while ((priv = stub_priv_pop(sdev))) {
258 urb = priv->urb;
259 dev_dbg(&sdev->udev->dev, "free urb seqnum %lu\n",
260 priv->seqnum);
261 usb_kill_urb(urb);
262
263 kmem_cache_free(stub_priv_cache, priv);
264
265 kfree(urb->transfer_buffer);
266 urb->transfer_buffer = NULL;
267
268 kfree(urb->setup_packet);
269 urb->setup_packet = NULL;
270
271 usb_free_urb(urb);
272 }
273 }
274
usbip_host_init(void)275 static int __init usbip_host_init(void)
276 {
277 int ret;
278
279 init_busid_table();
280
281 stub_priv_cache = KMEM_CACHE(stub_priv, SLAB_HWCACHE_ALIGN);
282 if (!stub_priv_cache) {
283 pr_err("kmem_cache_create failed\n");
284 return -ENOMEM;
285 }
286
287 ret = usb_register_device_driver(&stub_driver, THIS_MODULE);
288 if (ret) {
289 pr_err("usb_register failed %d\n", ret);
290 goto err_usb_register;
291 }
292
293 ret = driver_create_file(&stub_driver.drvwrap.driver,
294 &driver_attr_match_busid);
295 if (ret) {
296 pr_err("driver_create_file failed\n");
297 goto err_create_file;
298 }
299
300 ret = driver_create_file(&stub_driver.drvwrap.driver,
301 &driver_attr_rebind);
302 if (ret) {
303 pr_err("driver_create_file failed\n");
304 goto err_create_file;
305 }
306
307 pr_info(DRIVER_DESC " v" USBIP_VERSION "\n");
308 return ret;
309
310 err_create_file:
311 usb_deregister_device_driver(&stub_driver);
312 err_usb_register:
313 kmem_cache_destroy(stub_priv_cache);
314 return ret;
315 }
316
usbip_host_exit(void)317 static void __exit usbip_host_exit(void)
318 {
319 driver_remove_file(&stub_driver.drvwrap.driver,
320 &driver_attr_match_busid);
321
322 driver_remove_file(&stub_driver.drvwrap.driver,
323 &driver_attr_rebind);
324
325 /*
326 * deregister() calls stub_disconnect() for all devices. Device
327 * specific data is cleared in stub_disconnect().
328 */
329 usb_deregister_device_driver(&stub_driver);
330
331 kmem_cache_destroy(stub_priv_cache);
332 }
333
334 module_init(usbip_host_init);
335 module_exit(usbip_host_exit);
336
337 MODULE_AUTHOR(DRIVER_AUTHOR);
338 MODULE_DESCRIPTION(DRIVER_DESC);
339 MODULE_LICENSE("GPL");
340 MODULE_VERSION(USBIP_VERSION);
341