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 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
  69 static
  70 struct 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;
 114 err:
 115         if (edev->sudev)
 116                 udev_device_unref(edev->sudev);
 117         if (edev)
 118                 free(edev);
 119
 120         return NULL;
 121 }
 122
 123 static 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
 160 static 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
 172 int 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;
 186 err:
 187         udev_unref(udev_context);
 188         return -1;
 189 }
 190
 191 void 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
 201 int 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
 217 int 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
 258 struct 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 }