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->cred->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  * Close device.
  85  * Return: 0 on success, negated errno on failure.
  86  * @inode:              Pointer to inode info structure.
  87  * @filp:               Associated file pointer.
  88  */
  89 static int vbg_misc_device_close(struct inode *inode, struct file *filp)
  90 {
  91         vbg_core_close_session(filp->private_data);
  92         filp->private_data = NULL;
  93         return 0;
  94 }
  95
  96 /**
  97  * Device I/O Control entry point.
  98  * Return: 0 on success, negated errno on failure.
  99  * @filp:               Associated file pointer.
 100  * @req:                The request specified to ioctl().
 101  * @arg:                The argument specified to ioctl().
 102  */
 103 static long vbg_misc_device_ioctl(struct file *filp, unsigned int req,
 104                                   unsigned long arg)
 105 {
 106         struct vbg_session *session = filp->private_data;
 107         size_t returned_size, size;
 108         struct vbg_ioctl_hdr hdr;
 109         bool is_vmmdev_req;
 110         int ret = 0;
 111         void *buf;
 112
 113         if (copy_from_user(&hdr, (void *)arg, sizeof(hdr)))
 114                 return -EFAULT;
 115
 116         if (hdr.version != VBG_IOCTL_HDR_VERSION)
 117                 return -EINVAL;
 118
 119         if (hdr.size_in < sizeof(hdr) ||
 120             (hdr.size_out && hdr.size_out < sizeof(hdr)))
 121                 return -EINVAL;
 122
 123         size = max(hdr.size_in, hdr.size_out);
 124         if (_IOC_SIZE(req) && _IOC_SIZE(req) != size)
 125                 return -EINVAL;
 126         if (size > SZ_16M)
 127                 return -E2BIG;
 128
 129         /*
 130          * IOCTL_VMMDEV_REQUEST needs the buffer to be below 4G to avoid
 131          * the need for a bounce-buffer and another copy later on.
 132          */
 133         is_vmmdev_req = (req & ~IOCSIZE_MASK) == VBG_IOCTL_VMMDEV_REQUEST(0) ||
 134                          req == VBG_IOCTL_VMMDEV_REQUEST_BIG;
 135
 136         if (is_vmmdev_req)
 137                 buf = vbg_req_alloc(size, VBG_IOCTL_HDR_TYPE_DEFAULT,
 138                                     session->requestor);
 139         else
 140                 buf = kmalloc(size, GFP_KERNEL);
 141         if (!buf)
 142                 return -ENOMEM;
 143
 144         *((struct vbg_ioctl_hdr *)buf) = hdr;
 145         if (copy_from_user(buf + sizeof(hdr), (void *)arg + sizeof(hdr),
 146                            hdr.size_in - sizeof(hdr))) {
 147                 ret = -EFAULT;
 148                 goto out;
 149         }
 150         if (hdr.size_in < size)
 151                 memset(buf + hdr.size_in, 0, size -  hdr.size_in);
 152
 153         ret = vbg_core_ioctl(session, req, buf);
 154         if (ret)
 155                 goto out;
 156
 157         returned_size = ((struct vbg_ioctl_hdr *)buf)->size_out;
 158         if (returned_size > size) {
 159                 vbg_debug("%s: too much output data %zu > %zu\n",
 160                           __func__, returned_size, size);
 161                 returned_size = size;
 162         }
 163         if (copy_to_user((void *)arg, buf, returned_size) != 0)
 164                 ret = -EFAULT;
 165
 166 out:
 167         if (is_vmmdev_req)
 168                 vbg_req_free(buf, size);
 169         else
 170                 kfree(buf);
 171
 172         return ret;
 173 }
 174
 175 /** The file_operations structures. */
 176 static const struct file_operations vbg_misc_device_fops = {
 177         .owner                  = THIS_MODULE,
 178         .open                   = vbg_misc_device_open,
 179         .release                = vbg_misc_device_close,
 180         .unlocked_ioctl         = vbg_misc_device_ioctl,
 181 #ifdef CONFIG_COMPAT
 182         .compat_ioctl           = vbg_misc_device_ioctl,
 183 #endif
 184 };
 185 static const struct file_operations vbg_misc_device_user_fops = {
 186         .owner                  = THIS_MODULE,
 187         .open                   = vbg_misc_device_user_open,
 188         .release                = vbg_misc_device_close,
 189         .unlocked_ioctl         = vbg_misc_device_ioctl,
 190 #ifdef CONFIG_COMPAT
 191         .compat_ioctl           = vbg_misc_device_ioctl,
 192 #endif
 193 };
 194
 195 /**
 196  * Called when the input device is first opened.
 197  *
 198  * Sets up absolute mouse reporting.
 199  */
 200 static int vbg_input_open(struct input_dev *input)
 201 {
 202         struct vbg_dev *gdev = input_get_drvdata(input);
 203         u32 feat = VMMDEV_MOUSE_GUEST_CAN_ABSOLUTE | VMMDEV_MOUSE_NEW_PROTOCOL;
 204         int ret;
 205
 206         ret = vbg_core_set_mouse_status(gdev, feat);
 207         if (ret)
 208                 return ret;
 209
 210         return 0;
 211 }
 212
 213 /**
 214  * Called if all open handles to the input device are closed.
 215  *
 216  * Disables absolute reporting.
 217  */
 218 static void vbg_input_close(struct input_dev *input)
 219 {
 220         struct vbg_dev *gdev = input_get_drvdata(input);
 221
 222         vbg_core_set_mouse_status(gdev, 0);
 223 }
 224
 225 /**
 226  * Creates the kernel input device.
 227  *
 228  * Return: 0 on success, negated errno on failure.
 229  */
 230 static int vbg_create_input_device(struct vbg_dev *gdev)
 231 {
 232         struct input_dev *input;
 233
 234         input = devm_input_allocate_device(gdev->dev);
 235         if (!input)
 236                 return -ENOMEM;
 237
 238         input->id.bustype = BUS_PCI;
 239         input->id.vendor = VBOX_VENDORID;
 240         input->id.product = VMMDEV_DEVICEID;
 241         input->open = vbg_input_open;
 242         input->close = vbg_input_close;
 243         input->dev.parent = gdev->dev;
 244         input->name = "VirtualBox mouse integration";
 245
 246         input_set_abs_params(input, ABS_X, VMMDEV_MOUSE_RANGE_MIN,
 247                              VMMDEV_MOUSE_RANGE_MAX, 0, 0);
 248         input_set_abs_params(input, ABS_Y, VMMDEV_MOUSE_RANGE_MIN,
 249                              VMMDEV_MOUSE_RANGE_MAX, 0, 0);
 250         input_set_capability(input, EV_KEY, BTN_MOUSE);
 251         input_set_drvdata(input, gdev);
 252
 253         gdev->input = input;
 254
 255         return input_register_device(gdev->input);
 256 }
 257
 258 static ssize_t host_version_show(struct device *dev,
 259                                  struct device_attribute *attr, char *buf)
 260 {
 261         struct vbg_dev *gdev = dev_get_drvdata(dev);
 262
 263         return sprintf(buf, "%s\n", gdev->host_version);
 264 }
 265
 266 static ssize_t host_features_show(struct device *dev,
 267                                  struct device_attribute *attr, char *buf)
 268 {
 269         struct vbg_dev *gdev = dev_get_drvdata(dev);
 270
 271         return sprintf(buf, "%#x\n", gdev->host_features);
 272 }
 273
 274 static DEVICE_ATTR_RO(host_version);
 275 static DEVICE_ATTR_RO(host_features);
 276
 277 /**
 278  * Does the PCI detection and init of the device.
 279  *
 280  * Return: 0 on success, negated errno on failure.
 281  */
 282 static int vbg_pci_probe(struct pci_dev *pci, const struct pci_device_id *id)
 283 {
 284         struct device *dev = &pci->dev;
 285         resource_size_t io, io_len, mmio, mmio_len;
 286         struct vmmdev_memory *vmmdev;
 287         struct vbg_dev *gdev;
 288         int ret;
 289
 290         gdev = devm_kzalloc(dev, sizeof(*gdev), GFP_KERNEL);
 291         if (!gdev)
 292                 return -ENOMEM;
 293
 294         ret = pci_enable_device(pci);
 295         if (ret != 0) {
 296                 vbg_err("vboxguest: Error enabling device: %d\n", ret);
 297                 return ret;
 298         }
 299
 300         ret = -ENODEV;
 301
 302         io = pci_resource_start(pci, 0);
 303         io_len = pci_resource_len(pci, 0);
 304         if (!io || !io_len) {
 305                 vbg_err("vboxguest: Error IO-port resource (0) is missing\n");
 306                 goto err_disable_pcidev;
 307         }
 308         if (devm_request_region(dev, io, io_len, DEVICE_NAME) == NULL) {
 309                 vbg_err("vboxguest: Error could not claim IO resource\n");
 310                 ret = -EBUSY;
 311                 goto err_disable_pcidev;
 312         }
 313
 314         mmio = pci_resource_start(pci, 1);
 315         mmio_len = pci_resource_len(pci, 1);
 316         if (!mmio || !mmio_len) {
 317                 vbg_err("vboxguest: Error MMIO resource (1) is missing\n");
 318                 goto err_disable_pcidev;
 319         }
 320
 321         if (devm_request_mem_region(dev, mmio, mmio_len, DEVICE_NAME) == NULL) {
 322                 vbg_err("vboxguest: Error could not claim MMIO resource\n");
 323                 ret = -EBUSY;
 324                 goto err_disable_pcidev;
 325         }
 326
 327         vmmdev = devm_ioremap(dev, mmio, mmio_len);
 328         if (!vmmdev) {
 329                 vbg_err("vboxguest: Error ioremap failed; MMIO addr=%pap size=%pap\n",
 330                         &mmio, &mmio_len);
 331                 goto err_disable_pcidev;
 332         }
 333
 334         /* Validate MMIO region version and size. */
 335         if (vmmdev->version != VMMDEV_MEMORY_VERSION ||
 336             vmmdev->size < 32 || vmmdev->size > mmio_len) {
 337                 vbg_err("vboxguest: Bogus VMMDev memory; version=%08x (expected %08x) size=%d (expected <= %d)\n",
 338                         vmmdev->version, VMMDEV_MEMORY_VERSION,
 339                         vmmdev->size, (int)mmio_len);
 340                 goto err_disable_pcidev;
 341         }
 342
 343         gdev->io_port = io;
 344         gdev->mmio = vmmdev;
 345         gdev->dev = dev;
 346         gdev->misc_device.minor = MISC_DYNAMIC_MINOR;
 347         gdev->misc_device.name = DEVICE_NAME;
 348         gdev->misc_device.fops = &vbg_misc_device_fops;
 349         gdev->misc_device_user.minor = MISC_DYNAMIC_MINOR;
 350         gdev->misc_device_user.name = DEVICE_NAME_USER;
 351         gdev->misc_device_user.fops = &vbg_misc_device_user_fops;
 352
 353         ret = vbg_core_init(gdev, VMMDEV_EVENT_MOUSE_POSITION_CHANGED);
 354         if (ret)
 355                 goto err_disable_pcidev;
 356
 357         ret = vbg_create_input_device(gdev);
 358         if (ret) {
 359                 vbg_err("vboxguest: Error creating input device: %d\n", ret);
 360                 goto err_vbg_core_exit;
 361         }
 362
 363         ret = devm_request_irq(dev, pci->irq, vbg_core_isr, IRQF_SHARED,
 364                                DEVICE_NAME, gdev);
 365         if (ret) {
 366                 vbg_err("vboxguest: Error requesting irq: %d\n", ret);
 367                 goto err_vbg_core_exit;
 368         }
 369
 370         ret = misc_register(&gdev->misc_device);
 371         if (ret) {
 372                 vbg_err("vboxguest: Error misc_register %s failed: %d\n",
 373                         DEVICE_NAME, ret);
 374                 goto err_vbg_core_exit;
 375         }
 376
 377         ret = misc_register(&gdev->misc_device_user);
 378         if (ret) {
 379                 vbg_err("vboxguest: Error misc_register %s failed: %d\n",
 380                         DEVICE_NAME_USER, ret);
 381                 goto err_unregister_misc_device;
 382         }
 383
 384         mutex_lock(&vbg_gdev_mutex);
 385         if (!vbg_gdev)
 386                 vbg_gdev = gdev;
 387         else
 388                 ret = -EBUSY;
 389         mutex_unlock(&vbg_gdev_mutex);
 390
 391         if (ret) {
 392                 vbg_err("vboxguest: Error more then 1 vbox guest pci device\n");
 393                 goto err_unregister_misc_device_user;
 394         }
 395
 396         pci_set_drvdata(pci, gdev);
 397         device_create_file(dev, &dev_attr_host_version);
 398         device_create_file(dev, &dev_attr_host_features);
 399
 400         vbg_info("vboxguest: misc device minor %d, IRQ %d, I/O port %x, MMIO at %pap (size %pap)\n",
 401                  gdev->misc_device.minor, pci->irq, gdev->io_port,
 402                  &mmio, &mmio_len);
 403
 404         return 0;
 405
 406 err_unregister_misc_device_user:
 407         misc_deregister(&gdev->misc_device_user);
 408 err_unregister_misc_device:
 409         misc_deregister(&gdev->misc_device);
 410 err_vbg_core_exit:
 411         vbg_core_exit(gdev);
 412 err_disable_pcidev:
 413         pci_disable_device(pci);
 414
 415         return ret;
 416 }
 417
 418 static void vbg_pci_remove(struct pci_dev *pci)
 419 {
 420         struct vbg_dev *gdev = pci_get_drvdata(pci);
 421
 422         mutex_lock(&vbg_gdev_mutex);
 423         vbg_gdev = NULL;
 424         mutex_unlock(&vbg_gdev_mutex);
 425
 426         device_remove_file(gdev->dev, &dev_attr_host_features);
 427         device_remove_file(gdev->dev, &dev_attr_host_version);
 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         .id_table       = vbg_pci_ids,
 493         .probe          = vbg_pci_probe,
 494         .remove         = vbg_pci_remove,
 495 };
 496
 497 module_pci_driver(vbg_pci_driver);
 498
 499 MODULE_AUTHOR("Oracle Corporation");
 500 MODULE_DESCRIPTION("Oracle VM VirtualBox Guest Additions for Linux Module");
 501 MODULE_LICENSE("GPL");