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/kthread.h>
 21#include <linux/file.h>
 22#include <linux/net.h>
 23
 24#include "usbip_common.h"
 25#include "vhci.h"
 26
 27/* TODO: refine locking ?*/
 28
 29/* Sysfs entry to show port status */
 30static ssize_t status_show(struct device *dev, struct device_attribute *attr,
 31			   char *out)
 32{
 33	char *s = out;
 34	int i = 0;
 35	unsigned long flags;
 36
 37	BUG_ON(!the_controller || !out);
 38
 39	spin_lock_irqsave(&the_controller->lock, flags);
 40
 41	/*
 42	 * output example:
 43	 * prt sta spd dev socket           local_busid
 44	 * 000 004 000 000         c5a7bb80 1-2.3
 45	 * 001 004 000 000         d8cee980 2-3.4
 46	 *
 47	 * IP address can be retrieved from a socket pointer address by looking
 48	 * up /proc/net/{tcp,tcp6}. Also, a userland program may remember a
 49	 * port number and its peer IP address.
 50	 */
 51	out += sprintf(out,
 52		       "prt sta spd bus dev socket           local_busid\n");
 53
 54	for (i = 0; i < VHCI_NPORTS; i++) {
 55		struct vhci_device *vdev = port_to_vdev(i);
 56
 57		spin_lock(&vdev->ud.lock);
 58		out += sprintf(out, "%03u %03u ", i, vdev->ud.status);
 59
 60		if (vdev->ud.status == VDEV_ST_USED) {
 61			out += sprintf(out, "%03u %08x ",
 62				       vdev->speed, vdev->devid);
 63			out += sprintf(out, "%16p ", vdev->ud.tcp_socket);
 64			out += sprintf(out, "%s", dev_name(&vdev->udev->dev));
 65
 66		} else {
 67			out += sprintf(out, "000 000 000 0000000000000000 0-0");
 68		}
 69
 70		out += sprintf(out, "\n");
 71		spin_unlock(&vdev->ud.lock);
 72	}
 73
 74	spin_unlock_irqrestore(&the_controller->lock, flags);
 75
 76	return out - s;
 77}
 78static DEVICE_ATTR_RO(status);
 79
 80/* Sysfs entry to shutdown a virtual connection */
 81static int vhci_port_disconnect(__u32 rhport)
 82{
 83	struct vhci_device *vdev;
 84	unsigned long flags;
 85
 86	usbip_dbg_vhci_sysfs("enter\n");
 87
 88	/* lock */
 89	spin_lock_irqsave(&the_controller->lock, flags);
 90
 91	vdev = port_to_vdev(rhport);
 92
 93	spin_lock(&vdev->ud.lock);
 94	if (vdev->ud.status == VDEV_ST_NULL) {
 95		pr_err("not connected %d\n", vdev->ud.status);
 96
 97		/* unlock */
 98		spin_unlock(&vdev->ud.lock);
 99		spin_unlock_irqrestore(&the_controller->lock, flags);
100
101		return -EINVAL;
102	}
103
104	/* unlock */
105	spin_unlock(&vdev->ud.lock);
106	spin_unlock_irqrestore(&the_controller->lock, flags);
107
108	usbip_event_add(&vdev->ud, VDEV_EVENT_DOWN);
109
110	return 0;
111}
112
113static ssize_t store_detach(struct device *dev, struct device_attribute *attr,
114			    const char *buf, size_t count)
115{
116	int err;
117	__u32 rhport = 0;
118
119	if (sscanf(buf, "%u", &rhport) != 1)
120		return -EINVAL;
121
122	/* check rhport */
123	if (rhport >= VHCI_NPORTS) {
124		dev_err(dev, "invalid port %u\n", rhport);
125		return -EINVAL;
126	}
127
128	err = vhci_port_disconnect(rhport);
129	if (err < 0)
130		return -EINVAL;
131
132	usbip_dbg_vhci_sysfs("Leave\n");
133
134	return count;
135}
136static DEVICE_ATTR(detach, S_IWUSR, NULL, store_detach);
137
138/* Sysfs entry to establish a virtual connection */
139static int valid_args(__u32 rhport, enum usb_device_speed speed)
140{
141	/* check rhport */
142	if (rhport >= VHCI_NPORTS) {
143		pr_err("port %u\n", rhport);
144		return -EINVAL;
145	}
146
147	/* check speed */
148	switch (speed) {
149	case USB_SPEED_LOW:
150	case USB_SPEED_FULL:
151	case USB_SPEED_HIGH:
152	case USB_SPEED_WIRELESS:
153		break;
154	default:
155		pr_err("Failed attach request for unsupported USB speed: %s\n",
156			usb_speed_string(speed));
157		return -EINVAL;
158	}
159
160	return 0;
161}
162
163/*
164 * To start a new USB/IP attachment, a userland program needs to setup a TCP
165 * connection and then write its socket descriptor with remote device
166 * information into this sysfs file.
167 *
168 * A remote device is virtually attached to the root-hub port of @rhport with
169 * @speed. @devid is embedded into a request to specify the remote device in a
170 * server host.
171 *
172 * write() returns 0 on success, else negative errno.
173 */
174static ssize_t store_attach(struct device *dev, struct device_attribute *attr,
175			    const char *buf, size_t count)
176{
177	struct vhci_device *vdev;
178	struct socket *socket;
179	int sockfd = 0;
180	__u32 rhport = 0, devid = 0, speed = 0;
181	int err;
182	unsigned long flags;
183
184	/*
185	 * @rhport: port number of vhci_hcd
186	 * @sockfd: socket descriptor of an established TCP connection
187	 * @devid: unique device identifier in a remote host
188	 * @speed: usb device speed in a remote host
189	 */
190	if (sscanf(buf, "%u %u %u %u", &rhport, &sockfd, &devid, &speed) != 4)
191		return -EINVAL;
192
193	usbip_dbg_vhci_sysfs("rhport(%u) sockfd(%u) devid(%u) speed(%u)\n",
194			     rhport, sockfd, devid, speed);
195
196	/* check received parameters */
197	if (valid_args(rhport, speed) < 0)
198		return -EINVAL;
199
200	/* Extract socket from fd. */
201	socket = sockfd_lookup(sockfd, &err);
202	if (!socket)
203		return -EINVAL;
204
205	/* now need lock until setting vdev status as used */
206
207	/* begin a lock */
208	spin_lock_irqsave(&the_controller->lock, flags);
209	vdev = port_to_vdev(rhport);
210	spin_lock(&vdev->ud.lock);
211
212	if (vdev->ud.status != VDEV_ST_NULL) {
213		/* end of the lock */
214		spin_unlock(&vdev->ud.lock);
215		spin_unlock_irqrestore(&the_controller->lock, flags);
216
217		sockfd_put(socket);
218
219		dev_err(dev, "port %d already used\n", rhport);
220		return -EINVAL;
221	}
222
223	dev_info(dev,
224		 "rhport(%u) sockfd(%d) devid(%u) speed(%u) speed_str(%s)\n",
225		 rhport, sockfd, devid, speed, usb_speed_string(speed));
226
227	vdev->devid         = devid;
228	vdev->speed         = speed;
229	vdev->ud.tcp_socket = socket;
230	vdev->ud.status     = VDEV_ST_NOTASSIGNED;
231
232	spin_unlock(&vdev->ud.lock);
233	spin_unlock_irqrestore(&the_controller->lock, flags);
234	/* end the lock */
235
236	vdev->ud.tcp_rx = kthread_get_run(vhci_rx_loop, &vdev->ud, "vhci_rx");
237	vdev->ud.tcp_tx = kthread_get_run(vhci_tx_loop, &vdev->ud, "vhci_tx");
238
239	rh_port_connect(rhport, speed);
240
241	return count;
242}
243static DEVICE_ATTR(attach, S_IWUSR, NULL, store_attach);
244
245static struct attribute *dev_attrs[] = {
246	&dev_attr_status.attr,
247	&dev_attr_detach.attr,
248	&dev_attr_attach.attr,
249	&dev_attr_usbip_debug.attr,
250	NULL,
251};
252
253const struct attribute_group dev_attr_group = {
254	.attrs = dev_attrs,
255};