drivers/usb/usbip/vhci_sysfs.c

   1 /*
   2  * Copyright (C) 2003-2008 Takahiro Hirofuchi
   3  * Copyright (C) 2015-2016 Nobuo Iwata
   4  *
   5  * This is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write to the Free Software
  17  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
  18  * USA.
  19  */
  20
  21 #include <linux/kthread.h>
  22 #include <linux/file.h>
  23 #include <linux/net.h>
  24 #include <linux/platform_device.h>
  25 #include <linux/slab.h>
  26
  27 #include "usbip_common.h"
  28 #include "vhci.h"
  29
  30 /* TODO: refine locking ?*/
  31
  32 /* Sysfs entry to show port status */
  33 static ssize_t status_show_vhci(int pdev_nr, char *out)
  34 {
  35         struct platform_device *pdev = *(vhci_pdevs + pdev_nr);
  36         struct vhci_hcd *vhci;
  37         char *s = out;
  38         int i = 0;
  39         unsigned long flags;
  40
  41         if (!pdev || !out) {
  42                 usbip_dbg_vhci_sysfs("show status error\n");
  43                 return 0;
  44         }
  45
  46         vhci = hcd_to_vhci(platform_get_drvdata(pdev));
  47
  48         spin_lock_irqsave(&vhci->lock, flags);
  49
  50         /*
  51          * output example:
  52          * port sta spd dev      socket           local_busid
  53          * 0000 004 000 00000000         c5a7bb80 1-2.3
  54          * 0001 004 000 00000000         d8cee980 2-3.4
  55          *
  56          * IP address can be retrieved from a socket pointer address by looking
  57          * up /proc/net/{tcp,tcp6}. Also, a userland program may remember a
  58          * port number and its peer IP address.
  59          */
  60         for (i = 0; i < VHCI_HC_PORTS; i++) {
  61                 struct vhci_device *vdev = &vhci->vdev[i];
  62
  63                 spin_lock(&vdev->ud.lock);
  64                 out += sprintf(out, "%04u %03u ",
  65                                     (pdev_nr * VHCI_HC_PORTS) + i,
  66                                     vdev->ud.status);
  67
  68                 if (vdev->ud.status == VDEV_ST_USED) {
  69                         out += sprintf(out, "%03u %08x ",
  70                                             vdev->speed, vdev->devid);
  71                         out += sprintf(out, "%16p %s",
  72                                             vdev->ud.tcp_socket,
  73                                             dev_name(&vdev->udev->dev));
  74
  75                 } else {
  76                         out += sprintf(out, "000 00000000 ");
  77                         out += sprintf(out, "0000000000000000 0-0");
  78                 }
  79
  80                 out += sprintf(out, "\n");
  81                 spin_unlock(&vdev->ud.lock);
  82         }
  83
  84         spin_unlock_irqrestore(&vhci->lock, flags);
  85
  86         return out - s;
  87 }
  88
  89 static ssize_t status_show_not_ready(int pdev_nr, char *out)
  90 {
  91         char *s = out;
  92         int i = 0;
  93
  94         for (i = 0; i < VHCI_HC_PORTS; i++) {
  95                 out += sprintf(out, "%04u %03u ",
  96                                     (pdev_nr * VHCI_HC_PORTS) + i,
  97                                     VDEV_ST_NOTASSIGNED);
  98                 out += sprintf(out, "000 00000000 0000000000000000 0-0");
  99                 out += sprintf(out, "\n");
 100         }
 101         return out - s;
 102 }
 103
 104 static int status_name_to_id(const char *name)
 105 {
 106         char *c;
 107         long val;
 108         int ret;
 109
 110         c = strchr(name, '.');
 111         if (c == NULL)
 112                 return 0;
 113
 114         ret = kstrtol(c+1, 10, &val);
 115         if (ret < 0)
 116                 return ret;
 117
 118         return val;
 119 }
 120
 121 static ssize_t status_show(struct device *dev,
 122                            struct device_attribute *attr, char *out)
 123 {
 124         char *s = out;
 125         int pdev_nr;
 126
 127         out += sprintf(out,
 128                        "port sta spd dev      socket           local_busid\n");
 129
 130         pdev_nr = status_name_to_id(attr->attr.name);
 131         if (pdev_nr < 0)
 132                 out += status_show_not_ready(pdev_nr, out);
 133         else
 134                 out += status_show_vhci(pdev_nr, out);
 135
 136         return out - s;
 137 }
 138
 139 static ssize_t nports_show(struct device *dev, struct device_attribute *attr,
 140                            char *out)
 141 {
 142         char *s = out;
 143
 144         out += sprintf(out, "%d\n", VHCI_HC_PORTS * vhci_num_controllers);
 145         return out - s;
 146 }
 147 static DEVICE_ATTR_RO(nports);
 148
 149 /* Sysfs entry to shutdown a virtual connection */
 150 static int vhci_port_disconnect(struct vhci_hcd *vhci, __u32 rhport)
 151 {
 152         struct vhci_device *vdev = &vhci->vdev[rhport];
 153         unsigned long flags;
 154
 155         usbip_dbg_vhci_sysfs("enter\n");
 156
 157         /* lock */
 158         spin_lock_irqsave(&vhci->lock, flags);
 159         spin_lock(&vdev->ud.lock);
 160
 161         if (vdev->ud.status == VDEV_ST_NULL) {
 162                 pr_err("not connected %d\n", vdev->ud.status);
 163
 164                 /* unlock */
 165                 spin_unlock(&vdev->ud.lock);
 166                 spin_unlock_irqrestore(&vhci->lock, flags);
 167
 168                 return -EINVAL;
 169         }
 170
 171         /* unlock */
 172         spin_unlock(&vdev->ud.lock);
 173         spin_unlock_irqrestore(&vhci->lock, flags);
 174
 175         usbip_event_add(&vdev->ud, VDEV_EVENT_DOWN);
 176
 177         return 0;
 178 }
 179
 180 static int valid_port(__u32 pdev_nr, __u32 rhport)
 181 {
 182         if (pdev_nr >= vhci_num_controllers) {
 183                 pr_err("pdev %u\n", pdev_nr);
 184                 return 0;
 185         }
 186         if (rhport >= VHCI_HC_PORTS) {
 187                 pr_err("rhport %u\n", rhport);
 188                 return 0;
 189         }
 190         return 1;
 191 }
 192
 193 static ssize_t store_detach(struct device *dev, struct device_attribute *attr,
 194                             const char *buf, size_t count)
 195 {
 196         __u32 port = 0, pdev_nr = 0, rhport = 0;
 197         struct usb_hcd *hcd;
 198         int ret;
 199
 200         if (kstrtoint(buf, 10, &port) < 0)
 201                 return -EINVAL;
 202
 203         pdev_nr = port_to_pdev_nr(port);
 204         rhport = port_to_rhport(port);
 205
 206         if (!valid_port(pdev_nr, rhport))
 207                 return -EINVAL;
 208
 209         hcd = platform_get_drvdata(*(vhci_pdevs + pdev_nr));
 210         if (hcd == NULL) {
 211                 dev_err(dev, "port is not ready %u\n", port);
 212                 return -EAGAIN;
 213         }
 214
 215         ret = vhci_port_disconnect(hcd_to_vhci(hcd), rhport);
 216         if (ret < 0)
 217                 return -EINVAL;
 218
 219         usbip_dbg_vhci_sysfs("Leave\n");
 220
 221         return count;
 222 }
 223 static DEVICE_ATTR(detach, S_IWUSR, NULL, store_detach);
 224
 225 static int valid_args(__u32 pdev_nr, __u32 rhport, enum usb_device_speed speed)
 226 {
 227         if (!valid_port(pdev_nr, rhport)) {
 228                 return 0;
 229         }
 230
 231         switch (speed) {
 232         case USB_SPEED_LOW:
 233         case USB_SPEED_FULL:
 234         case USB_SPEED_HIGH:
 235         case USB_SPEED_WIRELESS:
 236                 break;
 237         default:
 238                 pr_err("Failed attach request for unsupported USB speed: %s\n",
 239                         usb_speed_string(speed));
 240                 return 0;
 241         }
 242
 243         return 1;
 244 }
 245
 246 /* Sysfs entry to establish a virtual connection */
 247 /*
 248  * To start a new USB/IP attachment, a userland program needs to setup a TCP
 249  * connection and then write its socket descriptor with remote device
 250  * information into this sysfs file.
 251  *
 252  * A remote device is virtually attached to the root-hub port of @rhport with
 253  * @speed. @devid is embedded into a request to specify the remote device in a
 254  * server host.
 255  *
 256  * write() returns 0 on success, else negative errno.
 257  */
 258 static ssize_t store_attach(struct device *dev, struct device_attribute *attr,
 259                             const char *buf, size_t count)
 260 {
 261         struct socket *socket;
 262         int sockfd = 0;
 263         __u32 port = 0, pdev_nr = 0, rhport = 0, devid = 0, speed = 0;
 264         struct usb_hcd *hcd;
 265         struct vhci_hcd *vhci;
 266         struct vhci_device *vdev;
 267         int err;
 268         unsigned long flags;
 269
 270         /*
 271          * @rhport: port number of vhci_hcd
 272          * @sockfd: socket descriptor of an established TCP connection
 273          * @devid: unique device identifier in a remote host
 274          * @speed: usb device speed in a remote host
 275          */
 276         if (sscanf(buf, "%u %u %u %u", &port, &sockfd, &devid, &speed) != 4)
 277                 return -EINVAL;
 278         pdev_nr = port_to_pdev_nr(port);
 279         rhport = port_to_rhport(port);
 280
 281         usbip_dbg_vhci_sysfs("port(%u) pdev(%d) rhport(%u)\n",
 282                              port, pdev_nr, rhport);
 283         usbip_dbg_vhci_sysfs("sockfd(%u) devid(%u) speed(%u)\n",
 284                              sockfd, devid, speed);
 285
 286         /* check received parameters */
 287         if (!valid_args(pdev_nr, rhport, speed))
 288                 return -EINVAL;
 289
 290         hcd = platform_get_drvdata(*(vhci_pdevs + pdev_nr));
 291         if (hcd == NULL) {
 292                 dev_err(dev, "port %d is not ready\n", port);
 293                 return -EAGAIN;
 294         }
 295         vhci = hcd_to_vhci(hcd);
 296         vdev = &vhci->vdev[rhport];
 297
 298         /* Extract socket from fd. */
 299         socket = sockfd_lookup(sockfd, &err);
 300         if (!socket)
 301                 return -EINVAL;
 302
 303         /* now need lock until setting vdev status as used */
 304
 305         /* begin a lock */
 306         spin_lock_irqsave(&vhci->lock, flags);
 307         spin_lock(&vdev->ud.lock);
 308
 309         if (vdev->ud.status != VDEV_ST_NULL) {
 310                 /* end of the lock */
 311                 spin_unlock(&vdev->ud.lock);
 312                 spin_unlock_irqrestore(&vhci->lock, flags);
 313
 314                 sockfd_put(socket);
 315
 316                 dev_err(dev, "port %d already used\n", rhport);
 317                 return -EINVAL;
 318         }
 319
 320         dev_info(dev, "pdev(%u) rhport(%u) sockfd(%d)\n",
 321                  pdev_nr, rhport, sockfd);
 322         dev_info(dev, "devid(%u) speed(%u) speed_str(%s)\n",
 323                  devid, speed, usb_speed_string(speed));
 324
 325         vdev->devid         = devid;
 326         vdev->speed         = speed;
 327         vdev->ud.tcp_socket = socket;
 328         vdev->ud.status     = VDEV_ST_NOTASSIGNED;
 329
 330         spin_unlock(&vdev->ud.lock);
 331         spin_unlock_irqrestore(&vhci->lock, flags);
 332         /* end the lock */
 333
 334         vdev->ud.tcp_rx = kthread_get_run(vhci_rx_loop, &vdev->ud, "vhci_rx");
 335         vdev->ud.tcp_tx = kthread_get_run(vhci_tx_loop, &vdev->ud, "vhci_tx");
 336
 337         rh_port_connect(vdev, speed);
 338
 339         return count;
 340 }
 341 static DEVICE_ATTR(attach, S_IWUSR, NULL, store_attach);
 342
 343 #define MAX_STATUS_NAME 16
 344
 345 struct status_attr {
 346         struct device_attribute attr;
 347         char name[MAX_STATUS_NAME+1];
 348 };
 349
 350 static struct status_attr *status_attrs;
 351
 352 static void set_status_attr(int id)
 353 {
 354         struct status_attr *status;
 355
 356         status = status_attrs + id;
 357         if (id == 0)
 358                 strcpy(status->name, "status");
 359         else
 360                 snprintf(status->name, MAX_STATUS_NAME+1, "status.%d", id);
 361         status->attr.attr.name = status->name;
 362         status->attr.attr.mode = S_IRUGO;
 363         status->attr.show = status_show;
 364         sysfs_attr_init(&status->attr.attr);
 365 }
 366
 367 static int init_status_attrs(void)
 368 {
 369         int id;
 370
 371         status_attrs = kcalloc(vhci_num_controllers, sizeof(struct status_attr),
 372                                GFP_KERNEL);
 373         if (status_attrs == NULL)
 374                 return -ENOMEM;
 375
 376         for (id = 0; id < vhci_num_controllers; id++)
 377                 set_status_attr(id);
 378
 379         return 0;
 380 }
 381
 382 static void finish_status_attrs(void)
 383 {
 384         kfree(status_attrs);
 385 }
 386
 387 struct attribute_group vhci_attr_group = {
 388         .attrs = NULL,
 389 };
 390
 391 int vhci_init_attr_group(void)
 392 {
 393         struct attribute **attrs;
 394         int ret, i;
 395
 396         attrs = kcalloc((vhci_num_controllers + 5), sizeof(struct attribute *),
 397                         GFP_KERNEL);
 398         if (attrs == NULL)
 399                 return -ENOMEM;
 400
 401         ret = init_status_attrs();
 402         if (ret) {
 403                 kfree(attrs);
 404                 return ret;
 405         }
 406         *attrs = &dev_attr_nports.attr;
 407         *(attrs + 1) = &dev_attr_detach.attr;
 408         *(attrs + 2) = &dev_attr_attach.attr;
 409         *(attrs + 3) = &dev_attr_usbip_debug.attr;
 410         for (i = 0; i < vhci_num_controllers; i++)
 411                 *(attrs + i + 4) = &((status_attrs + i)->attr.attr);
 412         vhci_attr_group.attrs = attrs;
 413         return 0;
 414 }
 415
 416 void vhci_finish_attr_group(void)
 417 {
 418         finish_status_attrs();
 419         kfree(vhci_attr_group.attrs);
 420 }