tools/usb/usbip/libsrc/usbip_host_common.c

   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
  38 struct udev *udev_context;
  39
  40 static int32_t read_attr_usbip_status(struct usbip_usb_device *udev)
  41 {
  42         char status_attr_path[SYSFS_PATH_MAX];
  43         int size;
  44         int fd;
  45         int length;
  46         char status[2] = { 0 };
  47         int value = 0;
  48
  49         size = snprintf(status_attr_path, sizeof(status_attr_path),
  50                         "%s/usbip_status", udev->path);
  51         if (size < 0 || (unsigned int)size >= sizeof(status_attr_path)) {
  52                 err("usbip_status path length %i >= %lu or < 0", size,
  53                     (long unsigned)sizeof(status_attr_path));
  54                 return -1;
  55         }
  56
  57
  58         fd = open(status_attr_path, O_RDONLY);
  59         if (fd < 0) {
  60                 err("error opening attribute %s", status_attr_path);
  61                 return -1;
  62         }
  63
  64         length = read(fd, status, 1);
  65         if (length < 0) {
  66                 err("error reading attribute %s", status_attr_path);
  67                 close(fd);
  68                 return -1;
  69         }
  70
  71         value = atoi(status);
  72         close(fd);
  73         return value;
  74 }
  75
  76 static
  77 struct usbip_exported_device *usbip_exported_device_new(
  78                 struct usbip_host_driver *hdriver, const char *sdevpath)
  79 {
  80         struct usbip_exported_device *edev = NULL;
  81         struct usbip_exported_device *edev_old;
  82         size_t size;
  83         int i;
  84
  85         edev = calloc(1, sizeof(struct usbip_exported_device));
  86
  87         edev->sudev =
  88                 udev_device_new_from_syspath(udev_context, sdevpath);
  89         if (!edev->sudev) {
  90                 err("udev_device_new_from_syspath: %s", sdevpath);
  91                 goto err;
  92         }
  93
  94         if (hdriver->ops.read_device(edev->sudev, &edev->udev) < 0)
  95                 goto err;
  96
  97         edev->status = read_attr_usbip_status(&edev->udev);
  98         if (edev->status < 0)
  99                 goto err;
 100
 101         /* reallocate buffer to include usb interface data */
 102         size = sizeof(struct usbip_exported_device) +
 103                 edev->udev.bNumInterfaces * sizeof(struct usbip_usb_interface);
 104
 105         edev_old = edev;
 106         edev = realloc(edev, size);
 107         if (!edev) {
 108                 edev = edev_old;
 109                 dbg("realloc failed");
 110                 goto err;
 111         }
 112
 113         for (i = 0; i < edev->udev.bNumInterfaces; i++) {
 114                 /* vudc does not support reading interfaces */
 115                 if (!hdriver->ops.read_interface)
 116                         break;
 117                 hdriver->ops.read_interface(&edev->udev, i, &edev->uinf[i]);
 118         }
 119
 120         return edev;
 121 err:
 122         if (edev->sudev)
 123                 udev_device_unref(edev->sudev);
 124         if (edev)
 125                 free(edev);
 126
 127         return NULL;
 128 }
 129
 130 static int refresh_exported_devices(struct usbip_host_driver *hdriver)
 131 {
 132         struct usbip_exported_device *edev;
 133         struct udev_enumerate *enumerate;
 134         struct udev_list_entry *devices, *dev_list_entry;
 135         struct udev_device *dev;
 136         const char *path;
 137
 138         enumerate = udev_enumerate_new(udev_context);
 139         udev_enumerate_add_match_subsystem(enumerate, hdriver->udev_subsystem);
 140         udev_enumerate_scan_devices(enumerate);
 141
 142         devices = udev_enumerate_get_list_entry(enumerate);
 143
 144         udev_list_entry_foreach(dev_list_entry, devices) {
 145                 path = udev_list_entry_get_name(dev_list_entry);
 146                 dev = udev_device_new_from_syspath(udev_context,
 147                                                    path);
 148                 if (dev == NULL)
 149                         continue;
 150
 151                 /* Check whether device uses usbip driver. */
 152                 if (hdriver->ops.is_my_device(dev)) {
 153                         edev = usbip_exported_device_new(hdriver, path);
 154                         if (!edev) {
 155                                 dbg("usbip_exported_device_new failed");
 156                                 continue;
 157                         }
 158
 159                         list_add(&edev->node, &hdriver->edev_list);
 160                         hdriver->ndevs++;
 161                 }
 162         }
 163
 164         return 0;
 165 }
 166
 167 static void usbip_exported_device_destroy(struct list_head *devs)
 168 {
 169         struct list_head *i, *tmp;
 170         struct usbip_exported_device *edev;
 171
 172         list_for_each_safe(i, tmp, devs) {
 173                 edev = list_entry(i, struct usbip_exported_device, node);
 174                 list_del(i);
 175                 free(edev);
 176         }
 177 }
 178
 179 int usbip_generic_driver_open(struct usbip_host_driver *hdriver)
 180 {
 181         int rc;
 182
 183         udev_context = udev_new();
 184         if (!udev_context) {
 185                 err("udev_new failed");
 186                 return -1;
 187         }
 188
 189         rc = refresh_exported_devices(hdriver);
 190         if (rc < 0)
 191                 goto err;
 192         return 0;
 193 err:
 194         udev_unref(udev_context);
 195         return -1;
 196 }
 197
 198 void usbip_generic_driver_close(struct usbip_host_driver *hdriver)
 199 {
 200         if (!hdriver)
 201                 return;
 202
 203         usbip_exported_device_destroy(&hdriver->edev_list);
 204
 205         udev_unref(udev_context);
 206 }
 207
 208 int usbip_generic_refresh_device_list(struct usbip_host_driver *hdriver)
 209 {
 210         int rc;
 211
 212         usbip_exported_device_destroy(&hdriver->edev_list);
 213
 214         hdriver->ndevs = 0;
 215         INIT_LIST_HEAD(&hdriver->edev_list);
 216
 217         rc = refresh_exported_devices(hdriver);
 218         if (rc < 0)
 219                 return -1;
 220
 221         return 0;
 222 }
 223
 224 int usbip_export_device(struct usbip_exported_device *edev, int sockfd)
 225 {
 226         char attr_name[] = "usbip_sockfd";
 227         char sockfd_attr_path[SYSFS_PATH_MAX];
 228         int size;
 229         char sockfd_buff[30];
 230         int ret;
 231
 232         if (edev->status != SDEV_ST_AVAILABLE) {
 233                 dbg("device not available: %s", edev->udev.busid);
 234                 switch (edev->status) {
 235                 case SDEV_ST_ERROR:
 236                         dbg("status SDEV_ST_ERROR");
 237                         ret = ST_DEV_ERR;
 238                         break;
 239                 case SDEV_ST_USED:
 240                         dbg("status SDEV_ST_USED");
 241                         ret = ST_DEV_BUSY;
 242                         break;
 243                 default:
 244                         dbg("status unknown: 0x%x", edev->status);
 245                         ret = -1;
 246                 }
 247                 return ret;
 248         }
 249
 250         /* only the first interface is true */
 251         size = snprintf(sockfd_attr_path, sizeof(sockfd_attr_path), "%s/%s",
 252                         edev->udev.path, attr_name);
 253         if (size < 0 || (unsigned int)size >= sizeof(sockfd_attr_path)) {
 254                 err("exported device path length %i >= %lu or < 0", size,
 255                     (long unsigned)sizeof(sockfd_attr_path));
 256                 return -1;
 257         }
 258
 259         size = snprintf(sockfd_buff, sizeof(sockfd_buff), "%d\n", sockfd);
 260         if (size < 0 || (unsigned int)size >= sizeof(sockfd_buff)) {
 261                 err("socket length %i >= %lu or < 0", size,
 262                     (long unsigned)sizeof(sockfd_buff));
 263                 return -1;
 264         }
 265
 266         ret = write_sysfs_attribute(sockfd_attr_path, sockfd_buff,
 267                                     strlen(sockfd_buff));
 268         if (ret < 0) {
 269                 err("write_sysfs_attribute failed: sockfd %s to %s",
 270                     sockfd_buff, sockfd_attr_path);
 271                 return ret;
 272         }
 273
 274         info("connect: %s", edev->udev.busid);
 275
 276         return ret;
 277 }
 278
 279 struct usbip_exported_device *usbip_generic_get_device(
 280                 struct usbip_host_driver *hdriver, int num)
 281 {
 282         struct list_head *i;
 283         struct usbip_exported_device *edev;
 284         int cnt = 0;
 285
 286         list_for_each(i, &hdriver->edev_list) {
 287                 edev = list_entry(i, struct usbip_exported_device, node);
 288                 if (num == cnt)
 289                         return edev;
 290                 cnt++;
 291         }
 292
 293         return NULL;
 294 }