drivers/virt/vboxguest/vboxguest_linux.c

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 /*
   3  * vboxguest linux pci driver, char-dev and input-device code,
   4  *
   5  * Copyright (C) 2006-2016 Oracle Corporation
   6  */
   7
   8 #include <linux/cred.h>
   9 #include <linux/input.h>
  10 #include <linux/kernel.h>
  11 #include <linux/miscdevice.h>
  12 #include <linux/module.h>
  13 #include <linux/pci.h>
  14 #include <linux/poll.h>
  15 #include <linux/vbox_utils.h>
  16 #include "vboxguest_core.h"
  17
  18 /** The device name. */
  19 #define DEVICE_NAME             "vboxguest"
  20 /** The device name for the device node open to everyone. */
  21 #define DEVICE_NAME_USER        "vboxuser"
  22 /** VirtualBox PCI vendor ID. */
  23 #define VBOX_VENDORID           0x80ee
  24 /** VMMDev PCI card product ID. */
  25 #define VMMDEV_DEVICEID         0xcafe
  26
  27 /** Mutex protecting the global vbg_gdev pointer used by vbg_get/put_gdev. */
  28 static DEFINE_MUTEX(vbg_gdev_mutex);
  29 /** Global vbg_gdev pointer used by vbg_get/put_gdev. */
  30 static struct vbg_dev *vbg_gdev;
  31
  32 static u32 vbg_misc_device_requestor(struct inode *inode)
  33 {
  34         u32 requestor = VMMDEV_REQUESTOR_USERMODE |
  35                         VMMDEV_REQUESTOR_CON_DONT_KNOW |
  36                         VMMDEV_REQUESTOR_TRUST_NOT_GIVEN;
  37
  38         if (from_kuid(current_user_ns(), current_uid()) == 0)
  39                 requestor |= VMMDEV_REQUESTOR_USR_ROOT;
  40         else
  41                 requestor |= VMMDEV_REQUESTOR_USR_USER;
  42
  43         if (in_egroup_p(inode->i_gid))
  44                 requestor |= VMMDEV_REQUESTOR_GRP_VBOX;
  45
  46         return requestor;
  47 }
  48
  49 static int vbg_misc_device_open(struct inode *inode, struct file *filp)
  50 {
  51         struct vbg_session *session;
  52         struct vbg_dev *gdev;
  53
  54         /* misc_open sets filp->private_data to our misc device */
  55         gdev = container_of(filp->private_data, struct vbg_dev, misc_device);
  56
  57         session = vbg_core_open_session(gdev, vbg_misc_device_requestor(inode));
  58         if (IS_ERR(session))
  59                 return PTR_ERR(session);
  60
  61         filp->private_data = session;
  62         return 0;
  63 }
  64
  65 static int vbg_misc_device_user_open(struct inode *inode, struct file *filp)
  66 {
  67         struct vbg_session *session;
  68         struct vbg_dev *gdev;
  69
  70         /* misc_open sets filp->private_data to our misc device */
  71         gdev = container_of(filp->private_data, struct vbg_dev,
  72                             misc_device_user);
  73
  74         session = vbg_core_open_session(gdev, vbg_misc_device_requestor(inode) |
  75                                               VMMDEV_REQUESTOR_USER_DEVICE);
  76         if (IS_ERR(session))
  77                 return PTR_ERR(session);
  78
  79         filp->private_data = session;
  80         return 0;
  81 }
  82
  83 /**
  84  * vbg_misc_device_close - Close device.
  85  * @inode:              Pointer to inode info structure.
  86  * @filp:               Associated file pointer.
  87  *
  88  * Return: %0 on success, negated errno on failure.
  89  */
  90 static int vbg_misc_device_close(struct inode *inode, struct file *filp)
  91 {
  92         vbg_core_close_session(filp->private_data);
  93         filp->private_data = NULL;
  94         return 0;
  95 }
  96
  97 /**
  98  * vbg_misc_device_ioctl - Device I/O Control entry point.
  99  * @filp:               Associated file pointer.
 100  * @req:                The request specified to ioctl().
 101  * @arg:                The argument specified to ioctl().
 102  *
 103  * Return: %0 on success, negated errno on failure.
 104  */
 105 static long vbg_misc_device_ioctl(struct file *filp, unsigned int req,
 106                                   unsigned long arg)
 107 {
 108         struct vbg_session *session = filp->private_data;
 109         size_t returned_size, size;
 110         struct vbg_ioctl_hdr hdr;
 111         bool is_vmmdev_req;
 112         int ret = 0;
 113         void *buf;
 114
 115         if (copy_from_user(&hdr, (void *)arg, sizeof(hdr)))
 116                 return -EFAULT;
 117
 118         if (hdr.version != VBG_IOCTL_HDR_VERSION)
 119                 return -EINVAL;
 120
 121         if (hdr.size_in < sizeof(hdr) ||
 122             (hdr.size_out && hdr.size_out < sizeof(hdr)))
 123                 return -EINVAL;
 124
 125         size = max(hdr.size_in, hdr.size_out);
 126         if (_IOC_SIZE(req) && _IOC_SIZE(req) != size)
 127                 return -EINVAL;
 128         if (size > SZ_16M)
 129                 return -E2BIG;
 130
 131         /*
 132          * IOCTL_VMMDEV_REQUEST needs the buffer to be below 4G to avoid
 133          * the need for a bounce-buffer and another copy later on.
 134          */
 135         is_vmmdev_req = (req & ~IOCSIZE_MASK) == VBG_IOCTL_VMMDEV_REQUEST(0) ||
 136                          req == VBG_IOCTL_VMMDEV_REQUEST_BIG ||
 137                          req == VBG_IOCTL_VMMDEV_REQUEST_BIG_ALT;
 138
 139         if (is_vmmdev_req)
 140                 buf = vbg_req_alloc(size, VBG_IOCTL_HDR_TYPE_DEFAULT,
 141                                     session->requestor);
 142         else
 143                 buf = kmalloc(size, GFP_KERNEL);
 144         if (!buf)
 145                 return -ENOMEM;
 146
 147         *((struct vbg_ioctl_hdr *)buf) = hdr;
 148         if (copy_from_user(buf + sizeof(hdr), (void *)arg + sizeof(hdr),
 149                            hdr.size_in - sizeof(hdr))) {
 150                 ret = -EFAULT;
 151                 goto out;
 152         }
 153         if (hdr.size_in < size)
 154                 memset(buf + hdr.size_in, 0, size -  hdr.size_in);
 155
 156         ret = vbg_core_ioctl(session, req, buf);
 157         if (ret)
 158                 goto out;
 159
 160         returned_size = ((struct vbg_ioctl_hdr *)buf)->size_out;
 161         if (returned_size > size) {
 162                 vbg_debug("%s: too much output data %zu > %zu\n",
 163                           __func__, returned_size, size);
 164                 returned_size = size;
 165         }
 166         if (copy_to_user((void *)arg, buf, returned_size) != 0)
 167                 ret = -EFAULT;
 168
 169 out:
 170         if (is_vmmdev_req)
 171                 vbg_req_free(buf, size);
 172         else
 173                 kfree(buf);
 174
 175         return ret;
 176 }
 177
 178 /* The file_operations structures. */
 179 static const struct file_operations vbg_misc_device_fops = {
 180         .owner                  = THIS_MODULE,
 181         .open                   = vbg_misc_device_open,
 182         .release                = vbg_misc_device_close,
 183         .unlocked_ioctl         = vbg_misc_device_ioctl,
 184 #ifdef CONFIG_COMPAT
 185         .compat_ioctl           = vbg_misc_device_ioctl,
 186 #endif
 187 };
 188 static const struct file_operations vbg_misc_device_user_fops = {
 189         .owner                  = THIS_MODULE,
 190         .open                   = vbg_misc_device_user_open,
 191         .release                = vbg_misc_device_close,
 192         .unlocked_ioctl         = vbg_misc_device_ioctl,
 193 #ifdef CONFIG_COMPAT
 194         .compat_ioctl           = vbg_misc_device_ioctl,
 195 #endif
 196 };
 197
 198 /*
 199  * Called when the input device is first opened.
 200  *
 201  * Sets up absolute mouse reporting.
 202  */
 203 static int vbg_input_open(struct input_dev *input)
 204 {
 205         struct vbg_dev *gdev = input_get_drvdata(input);
 206         u32 feat = VMMDEV_MOUSE_GUEST_CAN_ABSOLUTE | VMMDEV_MOUSE_NEW_PROTOCOL;
 207
 208         return vbg_core_set_mouse_status(gdev, feat);
 209 }
 210
 211 /*
 212  * Called if all open handles to the input device are closed.
 213  *
 214  * Disables absolute reporting.
 215  */
 216 static void vbg_input_close(struct input_dev *input)
 217 {
 218         struct vbg_dev *gdev = input_get_drvdata(input);
 219
 220         vbg_core_set_mouse_status(gdev, 0);
 221 }
 222
 223 /*
 224  * Creates the kernel input device.
 225  *
 226  * Return: 0 on success, negated errno on failure.
 227  */
 228 static int vbg_create_input_device(struct vbg_dev *gdev)
 229 {
 230         struct input_dev *input;
 231
 232         input = devm_input_allocate_device(gdev->dev);
 233         if (!input)
 234                 return -ENOMEM;
 235
 236         input->id.bustype = BUS_PCI;
 237         input->id.vendor = VBOX_VENDORID;
 238         input->id.product = VMMDEV_DEVICEID;
 239         input->open = vbg_input_open;
 240         input->close = vbg_input_close;
 241         input->dev.parent = gdev->dev;
 242         input->name = "VirtualBox mouse integration";
 243
 244         input_set_abs_params(input, ABS_X, VMMDEV_MOUSE_RANGE_MIN,
 245                              VMMDEV_MOUSE_RANGE_MAX, 0, 0);
 246         input_set_abs_params(input, ABS_Y, VMMDEV_MOUSE_RANGE_MIN,
 247                              VMMDEV_MOUSE_RANGE_MAX, 0, 0);
 248         input_set_capability(input, EV_KEY, BTN_MOUSE);
 249         input_set_drvdata(input, gdev);
 250
 251         gdev->input = input;
 252
 253         return input_register_device(gdev->input);
 254 }
 255
 256 static ssize_t host_version_show(struct device *dev,
 257                                  struct device_attribute *attr, char *buf)
 258 {
 259         struct vbg_dev *gdev = dev_get_drvdata(dev);
 260
 261         return sprintf(buf, "%s\n", gdev->host_version);
 262 }
 263
 264 static ssize_t host_features_show(struct device *dev,
 265                                  struct device_attribute *attr, char *buf)
 266 {
 267         struct vbg_dev *gdev = dev_get_drvdata(dev);
 268
 269         return sprintf(buf, "%#x\n", gdev->host_features);
 270 }
 271
 272 static DEVICE_ATTR_RO(host_version);
 273 static DEVICE_ATTR_RO(host_features);
 274
 275 static struct attribute *vbg_pci_attrs[] = {
 276         &dev_attr_host_version.attr,
 277         &dev_attr_host_features.attr,
 278         NULL,
 279 };
 280 ATTRIBUTE_GROUPS(vbg_pci);
 281
 282 /*
 283  * Does the PCI detection and init of the device.
 284  *
 285  * Return: 0 on success, negated errno on failure.
 286  */
 287 static int vbg_pci_probe(struct pci_dev *pci, const struct pci_device_id *id)
 288 {
 289         struct device *dev = &pci->dev;
 290         resource_size_t io, io_len, mmio, mmio_len;
 291         struct vmmdev_memory *vmmdev;
 292         struct vbg_dev *gdev;
 293         int ret;
 294
 295         gdev = devm_kzalloc(dev, sizeof(*gdev), GFP_KERNEL);
 296         if (!gdev)
 297                 return -ENOMEM;
 298
 299         ret = pci_enable_device(pci);
 300         if (ret != 0) {
 301                 vbg_err("vboxguest: Error enabling device: %d\n", ret);
 302                 return ret;
 303         }
 304
 305         ret = -ENODEV;
 306
 307         io = pci_resource_start(pci, 0);
 308         io_len = pci_resource_len(pci, 0);
 309         if (!io || !io_len) {
 310                 vbg_err("vboxguest: Error IO-port resource (0) is missing\n");
 311                 goto err_disable_pcidev;
 312         }
 313         if (devm_request_region(dev, io, io_len, DEVICE_NAME) == NULL) {
 314                 vbg_err("vboxguest: Error could not claim IO resource\n");
 315                 ret = -EBUSY;
 316                 goto err_disable_pcidev;
 317         }
 318
 319         mmio = pci_resource_start(pci, 1);
 320         mmio_len = pci_resource_len(pci, 1);
 321         if (!mmio || !mmio_len) {
 322                 vbg_err("vboxguest: Error MMIO resource (1) is missing\n");
 323                 goto err_disable_pcidev;
 324         }
 325
 326         if (devm_request_mem_region(dev, mmio, mmio_len, DEVICE_NAME) == NULL) {
 327                 vbg_err("vboxguest: Error could not claim MMIO resource\n");
 328                 ret = -EBUSY;
 329                 goto err_disable_pcidev;
 330         }
 331
 332         vmmdev = devm_ioremap(dev, mmio, mmio_len);
 333         if (!vmmdev) {
 334                 vbg_err("vboxguest: Error ioremap failed; MMIO addr=%pap size=%pap\n",
 335                         &mmio, &mmio_len);
 336                 goto err_disable_pcidev;
 337         }
 338
 339         /* Validate MMIO region version and size. */
 340         if (vmmdev->version != VMMDEV_MEMORY_VERSION ||
 341             vmmdev->size < 32 || vmmdev->size > mmio_len) {
 342                 vbg_err("vboxguest: Bogus VMMDev memory; version=%08x (expected %08x) size=%d (expected <= %d)\n",
 343                         vmmdev->version, VMMDEV_MEMORY_VERSION,
 344                         vmmdev->size, (int)mmio_len);
 345                 goto err_disable_pcidev;
 346         }
 347
 348         gdev->io_port = io;
 349         gdev->mmio = vmmdev;
 350         gdev->dev = dev;
 351         gdev->misc_device.minor = MISC_DYNAMIC_MINOR;
 352         gdev->misc_device.name = DEVICE_NAME;
 353         gdev->misc_device.fops = &vbg_misc_device_fops;
 354         gdev->misc_device_user.minor = MISC_DYNAMIC_MINOR;
 355         gdev->misc_device_user.name = DEVICE_NAME_USER;
 356         gdev->misc_device_user.fops = &vbg_misc_device_user_fops;
 357
 358         ret = vbg_core_init(gdev, VMMDEV_EVENT_MOUSE_POSITION_CHANGED);
 359         if (ret)
 360                 goto err_disable_pcidev;
 361
 362         ret = vbg_create_input_device(gdev);
 363         if (ret) {
 364                 vbg_err("vboxguest: Error creating input device: %d\n", ret);
 365                 goto err_vbg_core_exit;
 366         }
 367
 368         ret = request_irq(pci->irq, vbg_core_isr, IRQF_SHARED, DEVICE_NAME,
 369                           gdev);
 370         if (ret) {
 371                 vbg_err("vboxguest: Error requesting irq: %d\n", ret);
 372                 goto err_vbg_core_exit;
 373         }
 374
 375         ret = misc_register(&gdev->misc_device);
 376         if (ret) {
 377                 vbg_err("vboxguest: Error misc_register %s failed: %d\n",
 378                         DEVICE_NAME, ret);
 379                 goto err_free_irq;
 380         }
 381
 382         ret = misc_register(&gdev->misc_device_user);
 383         if (ret) {
 384                 vbg_err("vboxguest: Error misc_register %s failed: %d\n",
 385                         DEVICE_NAME_USER, ret);
 386                 goto err_unregister_misc_device;
 387         }
 388
 389         mutex_lock(&vbg_gdev_mutex);
 390         if (!vbg_gdev)
 391                 vbg_gdev = gdev;
 392         else
 393                 ret = -EBUSY;
 394         mutex_unlock(&vbg_gdev_mutex);
 395
 396         if (ret) {
 397                 vbg_err("vboxguest: Error more then 1 vbox guest pci device\n");
 398                 goto err_unregister_misc_device_user;
 399         }
 400
 401         pci_set_drvdata(pci, gdev);
 402
 403         return 0;
 404
 405 err_unregister_misc_device_user:
 406         misc_deregister(&gdev->misc_device_user);
 407 err_unregister_misc_device:
 408         misc_deregister(&gdev->misc_device);
 409 err_free_irq:
 410         free_irq(pci->irq, gdev);
 411 err_vbg_core_exit:
 412         vbg_core_exit(gdev);
 413 err_disable_pcidev:
 414         pci_disable_device(pci);
 415
 416         return ret;
 417 }
 418
 419 static void vbg_pci_remove(struct pci_dev *pci)
 420 {
 421         struct vbg_dev *gdev = pci_get_drvdata(pci);
 422
 423         mutex_lock(&vbg_gdev_mutex);
 424         vbg_gdev = NULL;
 425         mutex_unlock(&vbg_gdev_mutex);
 426
 427         free_irq(pci->irq, gdev);
 428         misc_deregister(&gdev->misc_device_user);
 429         misc_deregister(&gdev->misc_device);
 430         vbg_core_exit(gdev);
 431         pci_disable_device(pci);
 432 }
 433
 434 struct vbg_dev *vbg_get_gdev(void)
 435 {
 436         mutex_lock(&vbg_gdev_mutex);
 437
 438         /*
 439          * Note on success we keep the mutex locked until vbg_put_gdev(),
 440          * this stops vbg_pci_remove from removing the device from underneath
 441          * vboxsf. vboxsf will only hold a reference for a short while.
 442          */
 443         if (vbg_gdev)
 444                 return vbg_gdev;
 445
 446         mutex_unlock(&vbg_gdev_mutex);
 447         return ERR_PTR(-ENODEV);
 448 }
 449 EXPORT_SYMBOL(vbg_get_gdev);
 450
 451 void vbg_put_gdev(struct vbg_dev *gdev)
 452 {
 453         WARN_ON(gdev != vbg_gdev);
 454         mutex_unlock(&vbg_gdev_mutex);
 455 }
 456 EXPORT_SYMBOL(vbg_put_gdev);
 457
 458 /*
 459  * Callback for mouse events.
 460  *
 461  * This is called at the end of the ISR, after leaving the event spinlock, if
 462  * VMMDEV_EVENT_MOUSE_POSITION_CHANGED was raised by the host.
 463  *
 464  * @gdev:               The device extension.
 465  */
 466 void vbg_linux_mouse_event(struct vbg_dev *gdev)
 467 {
 468         int rc;
 469
 470         /* Report events to the kernel input device */
 471         gdev->mouse_status_req->mouse_features = 0;
 472         gdev->mouse_status_req->pointer_pos_x = 0;
 473         gdev->mouse_status_req->pointer_pos_y = 0;
 474         rc = vbg_req_perform(gdev, gdev->mouse_status_req);
 475         if (rc >= 0) {
 476                 input_report_abs(gdev->input, ABS_X,
 477                                  gdev->mouse_status_req->pointer_pos_x);
 478                 input_report_abs(gdev->input, ABS_Y,
 479                                  gdev->mouse_status_req->pointer_pos_y);
 480                 input_sync(gdev->input);
 481         }
 482 }
 483
 484 static const struct pci_device_id vbg_pci_ids[] = {
 485         { .vendor = VBOX_VENDORID, .device = VMMDEV_DEVICEID },
 486         {}
 487 };
 488 MODULE_DEVICE_TABLE(pci,  vbg_pci_ids);
 489
 490 static struct pci_driver vbg_pci_driver = {
 491         .name           = DEVICE_NAME,
 492         .dev_groups     = vbg_pci_groups,
 493         .id_table       = vbg_pci_ids,
 494         .probe          = vbg_pci_probe,
 495         .remove         = vbg_pci_remove,
 496 };
 497
 498 module_pci_driver(vbg_pci_driver);
 499
 500 MODULE_AUTHOR("Oracle Corporation");
 501 MODULE_DESCRIPTION("Oracle VM VirtualBox Guest Additions for Linux Module");
 502 MODULE_LICENSE("GPL");