1/*
  2 * Copyright (C) 2015-2016 Samsung Electronics
  3 *               Igor Kotrasinski <i.kotrasinsk@samsung.com>
  4 *               Krzysztof Opasiak <k.opasiak@samsung.com>
  5 *
  6 * Refactored from usbip_host_driver.c, which is:
  7 * Copyright (C) 2011 matt mooney <mfm@muteddisk.com>
  8 *               2005-2007 Takahiro Hirofuchi
  9 *
 10 * This program is free software: you can redistribute it and/or modify
 11 * it under the terms of the GNU General Public License as published by
 12 * the Free Software Foundation, either version 2 of the License, or
 13 * (at your option) any later version.
 14 *
 15 * This program is distributed in the hope that it will be useful,
 16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 18 * GNU General Public License for more details.
 19 *
 20 * You should have received a copy of the GNU General Public License
 21 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 22 */
 23
 24#include <sys/types.h>
 25#include <sys/stat.h>
 26#include <fcntl.h>
 27
 28#include <errno.h>
 29#include <unistd.h>
 30
 31#include <libudev.h>
 32
 33#include "usbip_common.h"
 34#include "usbip_host_common.h"
 35#include "list.h"
 36#include "sysfs_utils.h"
 37
 38struct udev *udev_context;
 39
 40static int32_t read_attr_usbip_status(struct usbip_usb_device *udev)
 41{
 42	char status_attr_path[SYSFS_PATH_MAX];
 43	int fd;
 44	int length;
 45	char status;
 46	int value = 0;
 47
 48	snprintf(status_attr_path, SYSFS_PATH_MAX, "%s/usbip_status",
 49		 udev->path);
 50
 51	fd = open(status_attr_path, O_RDONLY);
 52	if (fd < 0) {
 53		err("error opening attribute %s", status_attr_path);
 54		return -1;
 55	}
 56
 57	length = read(fd, &status, 1);
 58	if (length < 0) {
 59		err("error reading attribute %s", status_attr_path);
 60		close(fd);
 61		return -1;
 62	}
 63
 64	value = atoi(&status);
 65
 66	return value;
 67}
 68
 69static
 70struct usbip_exported_device *usbip_exported_device_new(
 71		struct usbip_host_driver *hdriver, const char *sdevpath)
 72{
 73	struct usbip_exported_device *edev = NULL;
 74	struct usbip_exported_device *edev_old;
 75	size_t size;
 76	int i;
 77
 78	edev = calloc(1, sizeof(struct usbip_exported_device));
 79
 80	edev->sudev =
 81		udev_device_new_from_syspath(udev_context, sdevpath);
 82	if (!edev->sudev) {
 83		err("udev_device_new_from_syspath: %s", sdevpath);
 84		goto err;
 85	}
 86
 87	if (hdriver->ops.read_device(edev->sudev, &edev->udev) < 0)
 88		goto err;
 89
 90	edev->status = read_attr_usbip_status(&edev->udev);
 91	if (edev->status < 0)
 92		goto err;
 93
 94	/* reallocate buffer to include usb interface data */
 95	size = sizeof(struct usbip_exported_device) +
 96		edev->udev.bNumInterfaces * sizeof(struct usbip_usb_interface);
 97
 98	edev_old = edev;
 99	edev = realloc(edev, size);
100	if (!edev) {
101		edev = edev_old;
102		dbg("realloc failed");
103		goto err;
104	}
105
106	for (i = 0; i < edev->udev.bNumInterfaces; i++) {
107		/* vudc does not support reading interfaces */
108		if (!hdriver->ops.read_interface)
109			break;
110		hdriver->ops.read_interface(&edev->udev, i, &edev->uinf[i]);
111	}
112
113	return edev;
114err:
115	if (edev->sudev)
116		udev_device_unref(edev->sudev);
117	if (edev)
118		free(edev);
119
120	return NULL;
121}
122
123static int refresh_exported_devices(struct usbip_host_driver *hdriver)
124{
125	struct usbip_exported_device *edev;
126	struct udev_enumerate *enumerate;
127	struct udev_list_entry *devices, *dev_list_entry;
128	struct udev_device *dev;
129	const char *path;
130
131	enumerate = udev_enumerate_new(udev_context);
132	udev_enumerate_add_match_subsystem(enumerate, hdriver->udev_subsystem);
133	udev_enumerate_scan_devices(enumerate);
134
135	devices = udev_enumerate_get_list_entry(enumerate);
136
137	udev_list_entry_foreach(dev_list_entry, devices) {
138		path = udev_list_entry_get_name(dev_list_entry);
139		dev = udev_device_new_from_syspath(udev_context,
140						   path);
141		if (dev == NULL)
142			continue;
143
144		/* Check whether device uses usbip driver. */
145		if (hdriver->ops.is_my_device(dev)) {
146			edev = usbip_exported_device_new(hdriver, path);
147			if (!edev) {
148				dbg("usbip_exported_device_new failed");
149				continue;
150			}
151
152			list_add(&edev->node, &hdriver->edev_list);
153			hdriver->ndevs++;
154		}
155	}
156
157	return 0;
158}
159
160static void usbip_exported_device_destroy(struct list_head *devs)
161{
162	struct list_head *i, *tmp;
163	struct usbip_exported_device *edev;
164
165	list_for_each_safe(i, tmp, devs) {
166		edev = list_entry(i, struct usbip_exported_device, node);
167		list_del(i);
168		free(edev);
169	}
170}
171
172int usbip_generic_driver_open(struct usbip_host_driver *hdriver)
173{
174	int rc;
175
176	udev_context = udev_new();
177	if (!udev_context) {
178		err("udev_new failed");
179		return -1;
180	}
181
182	rc = refresh_exported_devices(hdriver);
183	if (rc < 0)
184		goto err;
185	return 0;
186err:
187	udev_unref(udev_context);
188	return -1;
189}
190
191void usbip_generic_driver_close(struct usbip_host_driver *hdriver)
192{
193	if (!hdriver)
194		return;
195
196	usbip_exported_device_destroy(&hdriver->edev_list);
197
198	udev_unref(udev_context);
199}
200
201int usbip_generic_refresh_device_list(struct usbip_host_driver *hdriver)
202{
203	int rc;
204
205	usbip_exported_device_destroy(&hdriver->edev_list);
206
207	hdriver->ndevs = 0;
208	INIT_LIST_HEAD(&hdriver->edev_list);
209
210	rc = refresh_exported_devices(hdriver);
211	if (rc < 0)
212		return -1;
213
214	return 0;
215}
216
217int usbip_export_device(struct usbip_exported_device *edev, int sockfd)
218{
219	char attr_name[] = "usbip_sockfd";
220	char sockfd_attr_path[SYSFS_PATH_MAX];
221	char sockfd_buff[30];
222	int ret;
223
224	if (edev->status != SDEV_ST_AVAILABLE) {
225		dbg("device not available: %s", edev->udev.busid);
226		switch (edev->status) {
227		case SDEV_ST_ERROR:
228			dbg("status SDEV_ST_ERROR");
229			break;
230		case SDEV_ST_USED:
231			dbg("status SDEV_ST_USED");
232			break;
233		default:
234			dbg("status unknown: 0x%x", edev->status);
235		}
236		return -1;
237	}
238
239	/* only the first interface is true */
240	snprintf(sockfd_attr_path, sizeof(sockfd_attr_path), "%s/%s",
241		 edev->udev.path, attr_name);
242
243	snprintf(sockfd_buff, sizeof(sockfd_buff), "%d\n", sockfd);
244
245	ret = write_sysfs_attribute(sockfd_attr_path, sockfd_buff,
246				    strlen(sockfd_buff));
247	if (ret < 0) {
248		err("write_sysfs_attribute failed: sockfd %s to %s",
249		    sockfd_buff, sockfd_attr_path);
250		return ret;
251	}
252
253	info("connect: %s", edev->udev.busid);
254
255	return ret;
256}
257
258struct usbip_exported_device *usbip_generic_get_device(
259		struct usbip_host_driver *hdriver, int num)
260{
261	struct list_head *i;
262	struct usbip_exported_device *edev;
263	int cnt = 0;
264
265	list_for_each(i, &hdriver->edev_list) {
266		edev = list_entry(i, struct usbip_exported_device, node);
267		if (num == cnt)
268			return edev;
269		cnt++;
270	}
271
272	return NULL;
273}