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  * 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                          req == VBG_IOCTL_VMMDEV_REQUEST_BIG_ALT;
 136
 137         if (is_vmmdev_req)
 138                 buf = vbg_req_alloc(size, VBG_IOCTL_HDR_TYPE_DEFAULT,
 139                                     session->requestor);
 140         else
 141                 buf = kmalloc(size, GFP_KERNEL);
 142         if (!buf)
 143                 return -ENOMEM;
 144
 145         *((struct vbg_ioctl_hdr *)buf) = hdr;
 146         if (copy_from_user(buf + sizeof(hdr), (void *)arg + sizeof(hdr),
 147                            hdr.size_in - sizeof(hdr))) {
 148                 ret = -EFAULT;
 149                 goto out;
 150         }
 151         if (hdr.size_in < size)
 152                 memset(buf + hdr.size_in, 0, size -  hdr.size_in);
 153
 154         ret = vbg_core_ioctl(session, req, buf);
 155         if (ret)
 156                 goto out;
 157
 158         returned_size = ((struct vbg_ioctl_hdr *)buf)->size_out;
 159         if (returned_size > size) {
 160                 vbg_debug("%s: too much output data %zu > %zu\n",
 161                           __func__, returned_size, size);
 162                 returned_size = size;
 163         }
 164         if (copy_to_user((void *)arg, buf, returned_size) != 0)
 165                 ret = -EFAULT;
 166
 167 out:
 168         if (is_vmmdev_req)
 169                 vbg_req_free(buf, size);
 170         else
 171                 kfree(buf);
 172
 173         return ret;
 174 }
 175
 176 /** The file_operations structures. */
 177 static const struct file_operations vbg_misc_device_fops = {
 178         .owner                  = THIS_MODULE,
 179         .open                   = vbg_misc_device_open,
 180         .release                = vbg_misc_device_close,
 181         .unlocked_ioctl         = vbg_misc_device_ioctl,
 182 #ifdef CONFIG_COMPAT
 183         .compat_ioctl           = vbg_misc_device_ioctl,
 184 #endif
 185 };
 186 static const struct file_operations vbg_misc_device_user_fops = {
 187         .owner                  = THIS_MODULE,
 188         .open                   = vbg_misc_device_user_open,
 189         .release                = vbg_misc_device_close,
 190         .unlocked_ioctl         = vbg_misc_device_ioctl,
 191 #ifdef CONFIG_COMPAT
 192         .compat_ioctl           = vbg_misc_device_ioctl,
 193 #endif
 194 };
 195
 196 /**
 197  * Called when the input device is first opened.
 198  *
 199  * Sets up absolute mouse reporting.
 200  */
 201 static int vbg_input_open(struct input_dev *input)
 202 {
 203         struct vbg_dev *gdev = input_get_drvdata(input);
 204         u32 feat = VMMDEV_MOUSE_GUEST_CAN_ABSOLUTE | VMMDEV_MOUSE_NEW_PROTOCOL;
 205
 206         return vbg_core_set_mouse_status(gdev, feat);
 207 }
 208
 209 /**
 210  * Called if all open handles to the input device are closed.
 211  *
 212  * Disables absolute reporting.
 213  */
 214 static void vbg_input_close(struct input_dev *input)
 215 {
 216         struct vbg_dev *gdev = input_get_drvdata(input);
 217
 218         vbg_core_set_mouse_status(gdev, 0);
 219 }
 220
 221 /**
 222  * Creates the kernel input device.
 223  *
 224  * Return: 0 on success, negated errno on failure.
 225  */
 226 static int vbg_create_input_device(struct vbg_dev *gdev)
 227 {
 228         struct input_dev *input;
 229
 230         input = devm_input_allocate_device(gdev->dev);
 231         if (!input)
 232                 return -ENOMEM;
 233
 234         input->id.bustype = BUS_PCI;
 235         input->id.vendor = VBOX_VENDORID;
 236         input->id.product = VMMDEV_DEVICEID;
 237         input->open = vbg_input_open;
 238         input->close = vbg_input_close;
 239         input->dev.parent = gdev->dev;
 240         input->name = "VirtualBox mouse integration";
 241
 242         input_set_abs_params(input, ABS_X, VMMDEV_MOUSE_RANGE_MIN,
 243                              VMMDEV_MOUSE_RANGE_MAX, 0, 0);
 244         input_set_abs_params(input, ABS_Y, VMMDEV_MOUSE_RANGE_MIN,
 245                              VMMDEV_MOUSE_RANGE_MAX, 0, 0);
 246         input_set_capability(input, EV_KEY, BTN_MOUSE);
 247         input_set_drvdata(input, gdev);
 248
 249         gdev->input = input;
 250
 251         return input_register_device(gdev->input);
 252 }
 253
 254 static ssize_t host_version_show(struct device *dev,
 255                                  struct device_attribute *attr, char *buf)
 256 {
 257         struct vbg_dev *gdev = dev_get_drvdata(dev);
 258
 259         return sprintf(buf, "%s\n", gdev->host_version);
 260 }
 261
 262 static ssize_t host_features_show(struct device *dev,
 263                                  struct device_attribute *attr, char *buf)
 264 {
 265         struct vbg_dev *gdev = dev_get_drvdata(dev);
 266
 267         return sprintf(buf, "%#x\n", gdev->host_features);
 268 }
 269
 270 static DEVICE_ATTR_RO(host_version);
 271 static DEVICE_ATTR_RO(host_features);
 272
 273 /**
 274  * Does the PCI detection and init of the device.
 275  *
 276  * Return: 0 on success, negated errno on failure.
 277  */
 278 static int vbg_pci_probe(struct pci_dev *pci, const struct pci_device_id *id)
 279 {
 280         struct device *dev = &pci->dev;
 281         resource_size_t io, io_len, mmio, mmio_len;
 282         struct vmmdev_memory *vmmdev;
 283         struct vbg_dev *gdev;
 284         int ret;
 285
 286         gdev = devm_kzalloc(dev, sizeof(*gdev), GFP_KERNEL);
 287         if (!gdev)
 288                 return -ENOMEM;
 289
 290         ret = pci_enable_device(pci);
 291         if (ret != 0) {
 292                 vbg_err("vboxguest: Error enabling device: %d\n", ret);
 293                 return ret;
 294         }
 295
 296         ret = -ENODEV;
 297
 298         io = pci_resource_start(pci, 0);
 299         io_len = pci_resource_len(pci, 0);
 300         if (!io || !io_len) {
 301                 vbg_err("vboxguest: Error IO-port resource (0) is missing\n");
 302                 goto err_disable_pcidev;
 303         }
 304         if (devm_request_region(dev, io, io_len, DEVICE_NAME) == NULL) {
 305                 vbg_err("vboxguest: Error could not claim IO resource\n");
 306                 ret = -EBUSY;
 307                 goto err_disable_pcidev;
 308         }
 309
 310         mmio = pci_resource_start(pci, 1);
 311         mmio_len = pci_resource_len(pci, 1);
 312         if (!mmio || !mmio_len) {
 313                 vbg_err("vboxguest: Error MMIO resource (1) is missing\n");
 314                 goto err_disable_pcidev;
 315         }
 316
 317         if (devm_request_mem_region(dev, mmio, mmio_len, DEVICE_NAME) == NULL) {
 318                 vbg_err("vboxguest: Error could not claim MMIO resource\n");
 319                 ret = -EBUSY;
 320                 goto err_disable_pcidev;
 321         }
 322
 323         vmmdev = devm_ioremap(dev, mmio, mmio_len);
 324         if (!vmmdev) {
 325                 vbg_err("vboxguest: Error ioremap failed; MMIO addr=%pap size=%pap\n",
 326                         &mmio, &mmio_len);
 327                 goto err_disable_pcidev;
 328         }
 329
 330         /* Validate MMIO region version and size. */
 331         if (vmmdev->version != VMMDEV_MEMORY_VERSION ||
 332             vmmdev->size < 32 || vmmdev->size > mmio_len) {
 333                 vbg_err("vboxguest: Bogus VMMDev memory; version=%08x (expected %08x) size=%d (expected <= %d)\n",
 334                         vmmdev->version, VMMDEV_MEMORY_VERSION,
 335                         vmmdev->size, (int)mmio_len);
 336                 goto err_disable_pcidev;
 337         }
 338
 339         gdev->io_port = io;
 340         gdev->mmio = vmmdev;
 341         gdev->dev = dev;
 342         gdev->misc_device.minor = MISC_DYNAMIC_MINOR;
 343         gdev->misc_device.name = DEVICE_NAME;
 344         gdev->misc_device.fops = &vbg_misc_device_fops;
 345         gdev->misc_device_user.minor = MISC_DYNAMIC_MINOR;
 346         gdev->misc_device_user.name = DEVICE_NAME_USER;
 347         gdev->misc_device_user.fops = &vbg_misc_device_user_fops;
 348
 349         ret = vbg_core_init(gdev, VMMDEV_EVENT_MOUSE_POSITION_CHANGED);
 350         if (ret)
 351                 goto err_disable_pcidev;
 352
 353         ret = vbg_create_input_device(gdev);
 354         if (ret) {
 355                 vbg_err("vboxguest: Error creating input device: %d\n", ret);
 356                 goto err_vbg_core_exit;
 357         }
 358
 359         ret = devm_request_irq(dev, pci->irq, vbg_core_isr, IRQF_SHARED,
 360                                DEVICE_NAME, gdev);
 361         if (ret) {
 362                 vbg_err("vboxguest: Error requesting irq: %d\n", ret);
 363                 goto err_vbg_core_exit;
 364         }
 365
 366         ret = misc_register(&gdev->misc_device);
 367         if (ret) {
 368                 vbg_err("vboxguest: Error misc_register %s failed: %d\n",
 369                         DEVICE_NAME, ret);
 370                 goto err_vbg_core_exit;
 371         }
 372
 373         ret = misc_register(&gdev->misc_device_user);
 374         if (ret) {
 375                 vbg_err("vboxguest: Error misc_register %s failed: %d\n",
 376                         DEVICE_NAME_USER, ret);
 377                 goto err_unregister_misc_device;
 378         }
 379
 380         mutex_lock(&vbg_gdev_mutex);
 381         if (!vbg_gdev)
 382                 vbg_gdev = gdev;
 383         else
 384                 ret = -EBUSY;
 385         mutex_unlock(&vbg_gdev_mutex);
 386
 387         if (ret) {
 388                 vbg_err("vboxguest: Error more then 1 vbox guest pci device\n");
 389                 goto err_unregister_misc_device_user;
 390         }
 391
 392         pci_set_drvdata(pci, gdev);
 393         device_create_file(dev, &dev_attr_host_version);
 394         device_create_file(dev, &dev_attr_host_features);
 395
 396         vbg_info("vboxguest: misc device minor %d, IRQ %d, I/O port %x, MMIO at %pap (size %pap)\n",
 397                  gdev->misc_device.minor, pci->irq, gdev->io_port,
 398                  &mmio, &mmio_len);
 399
 400         return 0;
 401
 402 err_unregister_misc_device_user:
 403         misc_deregister(&gdev->misc_device_user);
 404 err_unregister_misc_device:
 405         misc_deregister(&gdev->misc_device);
 406 err_vbg_core_exit:
 407         vbg_core_exit(gdev);
 408 err_disable_pcidev:
 409         pci_disable_device(pci);
 410
 411         return ret;
 412 }
 413
 414 static void vbg_pci_remove(struct pci_dev *pci)
 415 {
 416         struct vbg_dev *gdev = pci_get_drvdata(pci);
 417
 418         mutex_lock(&vbg_gdev_mutex);
 419         vbg_gdev = NULL;
 420         mutex_unlock(&vbg_gdev_mutex);
 421
 422         device_remove_file(gdev->dev, &dev_attr_host_features);
 423         device_remove_file(gdev->dev, &dev_attr_host_version);
 424         misc_deregister(&gdev->misc_device_user);
 425         misc_deregister(&gdev->misc_device);
 426         vbg_core_exit(gdev);
 427         pci_disable_device(pci);
 428 }
 429
 430 struct vbg_dev *vbg_get_gdev(void)
 431 {
 432         mutex_lock(&vbg_gdev_mutex);
 433
 434         /*
 435          * Note on success we keep the mutex locked until vbg_put_gdev(),
 436          * this stops vbg_pci_remove from removing the device from underneath
 437          * vboxsf. vboxsf will only hold a reference for a short while.
 438          */
 439         if (vbg_gdev)
 440                 return vbg_gdev;
 441
 442         mutex_unlock(&vbg_gdev_mutex);
 443         return ERR_PTR(-ENODEV);
 444 }
 445 EXPORT_SYMBOL(vbg_get_gdev);
 446
 447 void vbg_put_gdev(struct vbg_dev *gdev)
 448 {
 449         WARN_ON(gdev != vbg_gdev);
 450         mutex_unlock(&vbg_gdev_mutex);
 451 }
 452 EXPORT_SYMBOL(vbg_put_gdev);
 453
 454 /**
 455  * Callback for mouse events.
 456  *
 457  * This is called at the end of the ISR, after leaving the event spinlock, if
 458  * VMMDEV_EVENT_MOUSE_POSITION_CHANGED was raised by the host.
 459  *
 460  * @gdev:               The device extension.
 461  */
 462 void vbg_linux_mouse_event(struct vbg_dev *gdev)
 463 {
 464         int rc;
 465
 466         /* Report events to the kernel input device */
 467         gdev->mouse_status_req->mouse_features = 0;
 468         gdev->mouse_status_req->pointer_pos_x = 0;
 469         gdev->mouse_status_req->pointer_pos_y = 0;
 470         rc = vbg_req_perform(gdev, gdev->mouse_status_req);
 471         if (rc >= 0) {
 472                 input_report_abs(gdev->input, ABS_X,
 473                                  gdev->mouse_status_req->pointer_pos_x);
 474                 input_report_abs(gdev->input, ABS_Y,
 475                                  gdev->mouse_status_req->pointer_pos_y);
 476                 input_sync(gdev->input);
 477         }
 478 }
 479
 480 static const struct pci_device_id vbg_pci_ids[] = {
 481         { .vendor = VBOX_VENDORID, .device = VMMDEV_DEVICEID },
 482         {}
 483 };
 484 MODULE_DEVICE_TABLE(pci,  vbg_pci_ids);
 485
 486 static struct pci_driver vbg_pci_driver = {
 487         .name           = DEVICE_NAME,
 488         .id_table       = vbg_pci_ids,
 489         .probe          = vbg_pci_probe,
 490         .remove         = vbg_pci_remove,
 491 };
 492
 493 module_pci_driver(vbg_pci_driver);
 494
 495 MODULE_AUTHOR("Oracle Corporation");
 496 MODULE_DESCRIPTION("Oracle VM VirtualBox Guest Additions for Linux Module");
 497 MODULE_LICENSE("GPL");