drivers/vfio/platform/vfio_platform_common.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (C) 2013 - Virtual Open Systems
   4  * Author: Antonios Motakis <a.motakis@virtualopensystems.com>
   5  */
   6
   7 #define dev_fmt(fmt)    "VFIO: " fmt
   8
   9 #include <linux/device.h>
  10 #include <linux/acpi.h>
  11 #include <linux/iommu.h>
  12 #include <linux/module.h>
  13 #include <linux/mutex.h>
  14 #include <linux/pm_runtime.h>
  15 #include <linux/slab.h>
  16 #include <linux/types.h>
  17 #include <linux/uaccess.h>
  18 #include <linux/vfio.h>
  19
  20 #include "vfio_platform_private.h"
  21
  22 #define DRIVER_VERSION  "0.10"
  23 #define DRIVER_AUTHOR   "Antonios Motakis <a.motakis@virtualopensystems.com>"
  24 #define DRIVER_DESC     "VFIO platform base module"
  25
  26 #define VFIO_PLATFORM_IS_ACPI(vdev) ((vdev)->acpihid != NULL)
  27
  28 static LIST_HEAD(reset_list);
  29 static DEFINE_MUTEX(driver_lock);
  30
  31 static vfio_platform_reset_fn_t vfio_platform_lookup_reset(const char *compat,
  32                                         struct module **module)
  33 {
  34         struct vfio_platform_reset_node *iter;
  35         vfio_platform_reset_fn_t reset_fn = NULL;
  36
  37         mutex_lock(&driver_lock);
  38         list_for_each_entry(iter, &reset_list, link) {
  39                 if (!strcmp(iter->compat, compat) &&
  40                         try_module_get(iter->owner)) {
  41                         *module = iter->owner;
  42                         reset_fn = iter->of_reset;
  43                         break;
  44                 }
  45         }
  46         mutex_unlock(&driver_lock);
  47         return reset_fn;
  48 }
  49
  50 static int vfio_platform_acpi_probe(struct vfio_platform_device *vdev,
  51                                     struct device *dev)
  52 {
  53         struct acpi_device *adev;
  54
  55         if (acpi_disabled)
  56                 return -ENOENT;
  57
  58         adev = ACPI_COMPANION(dev);
  59         if (!adev) {
  60                 dev_err(dev, "ACPI companion device not found for %s\n",
  61                         vdev->name);
  62                 return -ENODEV;
  63         }
  64
  65 #ifdef CONFIG_ACPI
  66         vdev->acpihid = acpi_device_hid(adev);
  67 #endif
  68         return WARN_ON(!vdev->acpihid) ? -EINVAL : 0;
  69 }
  70
  71 static int vfio_platform_acpi_call_reset(struct vfio_platform_device *vdev,
  72                                   const char **extra_dbg)
  73 {
  74 #ifdef CONFIG_ACPI
  75         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
  76         struct device *dev = vdev->device;
  77         acpi_handle handle = ACPI_HANDLE(dev);
  78         acpi_status acpi_ret;
  79
  80         acpi_ret = acpi_evaluate_object(handle, "_RST", NULL, &buffer);
  81         if (ACPI_FAILURE(acpi_ret)) {
  82                 if (extra_dbg)
  83                         *extra_dbg = acpi_format_exception(acpi_ret);
  84                 return -EINVAL;
  85         }
  86
  87         return 0;
  88 #else
  89         return -ENOENT;
  90 #endif
  91 }
  92
  93 static bool vfio_platform_acpi_has_reset(struct vfio_platform_device *vdev)
  94 {
  95 #ifdef CONFIG_ACPI
  96         struct device *dev = vdev->device;
  97         acpi_handle handle = ACPI_HANDLE(dev);
  98
  99         return acpi_has_method(handle, "_RST");
 100 #else
 101         return false;
 102 #endif
 103 }
 104
 105 static bool vfio_platform_has_reset(struct vfio_platform_device *vdev)
 106 {
 107         if (VFIO_PLATFORM_IS_ACPI(vdev))
 108                 return vfio_platform_acpi_has_reset(vdev);
 109
 110         return vdev->of_reset ? true : false;
 111 }
 112
 113 static int vfio_platform_get_reset(struct vfio_platform_device *vdev)
 114 {
 115         if (VFIO_PLATFORM_IS_ACPI(vdev))
 116                 return vfio_platform_acpi_has_reset(vdev) ? 0 : -ENOENT;
 117
 118         vdev->of_reset = vfio_platform_lookup_reset(vdev->compat,
 119                                                     &vdev->reset_module);
 120         if (!vdev->of_reset) {
 121                 request_module("vfio-reset:%s", vdev->compat);
 122                 vdev->of_reset = vfio_platform_lookup_reset(vdev->compat,
 123                                                         &vdev->reset_module);
 124         }
 125
 126         return vdev->of_reset ? 0 : -ENOENT;
 127 }
 128
 129 static void vfio_platform_put_reset(struct vfio_platform_device *vdev)
 130 {
 131         if (VFIO_PLATFORM_IS_ACPI(vdev))
 132                 return;
 133
 134         if (vdev->of_reset)
 135                 module_put(vdev->reset_module);
 136 }
 137
 138 static int vfio_platform_regions_init(struct vfio_platform_device *vdev)
 139 {
 140         int cnt = 0, i;
 141
 142         while (vdev->get_resource(vdev, cnt))
 143                 cnt++;
 144
 145         vdev->regions = kcalloc(cnt, sizeof(struct vfio_platform_region),
 146                                 GFP_KERNEL);
 147         if (!vdev->regions)
 148                 return -ENOMEM;
 149
 150         for (i = 0; i < cnt;  i++) {
 151                 struct resource *res =
 152                         vdev->get_resource(vdev, i);
 153
 154                 if (!res)
 155                         goto err;
 156
 157                 vdev->regions[i].addr = res->start;
 158                 vdev->regions[i].size = resource_size(res);
 159                 vdev->regions[i].flags = 0;
 160
 161                 switch (resource_type(res)) {
 162                 case IORESOURCE_MEM:
 163                         vdev->regions[i].type = VFIO_PLATFORM_REGION_TYPE_MMIO;
 164                         vdev->regions[i].flags |= VFIO_REGION_INFO_FLAG_READ;
 165                         if (!(res->flags & IORESOURCE_READONLY))
 166                                 vdev->regions[i].flags |=
 167                                         VFIO_REGION_INFO_FLAG_WRITE;
 168
 169                         /*
 170                          * Only regions addressed with PAGE granularity may be
 171                          * MMAPed securely.
 172                          */
 173                         if (!(vdev->regions[i].addr & ~PAGE_MASK) &&
 174                                         !(vdev->regions[i].size & ~PAGE_MASK))
 175                                 vdev->regions[i].flags |=
 176                                         VFIO_REGION_INFO_FLAG_MMAP;
 177
 178                         break;
 179                 case IORESOURCE_IO:
 180                         vdev->regions[i].type = VFIO_PLATFORM_REGION_TYPE_PIO;
 181                         break;
 182                 default:
 183                         goto err;
 184                 }
 185         }
 186
 187         vdev->num_regions = cnt;
 188
 189         return 0;
 190 err:
 191         kfree(vdev->regions);
 192         return -EINVAL;
 193 }
 194
 195 static void vfio_platform_regions_cleanup(struct vfio_platform_device *vdev)
 196 {
 197         int i;
 198
 199         for (i = 0; i < vdev->num_regions; i++)
 200                 iounmap(vdev->regions[i].ioaddr);
 201
 202         vdev->num_regions = 0;
 203         kfree(vdev->regions);
 204 }
 205
 206 static int vfio_platform_call_reset(struct vfio_platform_device *vdev,
 207                                     const char **extra_dbg)
 208 {
 209         if (VFIO_PLATFORM_IS_ACPI(vdev)) {
 210                 dev_info(vdev->device, "reset\n");
 211                 return vfio_platform_acpi_call_reset(vdev, extra_dbg);
 212         } else if (vdev->of_reset) {
 213                 dev_info(vdev->device, "reset\n");
 214                 return vdev->of_reset(vdev);
 215         }
 216
 217         dev_warn(vdev->device, "no reset function found!\n");
 218         return -EINVAL;
 219 }
 220
 221 static void vfio_platform_release(void *device_data)
 222 {
 223         struct vfio_platform_device *vdev = device_data;
 224
 225         mutex_lock(&driver_lock);
 226
 227         if (!(--vdev->refcnt)) {
 228                 const char *extra_dbg = NULL;
 229                 int ret;
 230
 231                 ret = vfio_platform_call_reset(vdev, &extra_dbg);
 232                 if (ret && vdev->reset_required) {
 233                         dev_warn(vdev->device, "reset driver is required and reset call failed in release (%d) %s\n",
 234                                  ret, extra_dbg ? extra_dbg : "");
 235                         WARN_ON(1);
 236                 }
 237                 pm_runtime_put(vdev->device);
 238                 vfio_platform_regions_cleanup(vdev);
 239                 vfio_platform_irq_cleanup(vdev);
 240         }
 241
 242         mutex_unlock(&driver_lock);
 243
 244         module_put(vdev->parent_module);
 245 }
 246
 247 static int vfio_platform_open(void *device_data)
 248 {
 249         struct vfio_platform_device *vdev = device_data;
 250         int ret;
 251
 252         if (!try_module_get(vdev->parent_module))
 253                 return -ENODEV;
 254
 255         mutex_lock(&driver_lock);
 256
 257         if (!vdev->refcnt) {
 258                 const char *extra_dbg = NULL;
 259
 260                 ret = vfio_platform_regions_init(vdev);
 261                 if (ret)
 262                         goto err_reg;
 263
 264                 ret = vfio_platform_irq_init(vdev);
 265                 if (ret)
 266                         goto err_irq;
 267
 268                 ret = pm_runtime_get_sync(vdev->device);
 269                 if (ret < 0)
 270                         goto err_pm;
 271
 272                 ret = vfio_platform_call_reset(vdev, &extra_dbg);
 273                 if (ret && vdev->reset_required) {
 274                         dev_warn(vdev->device, "reset driver is required and reset call failed in open (%d) %s\n",
 275                                  ret, extra_dbg ? extra_dbg : "");
 276                         goto err_rst;
 277                 }
 278         }
 279
 280         vdev->refcnt++;
 281
 282         mutex_unlock(&driver_lock);
 283         return 0;
 284
 285 err_rst:
 286         pm_runtime_put(vdev->device);
 287 err_pm:
 288         vfio_platform_irq_cleanup(vdev);
 289 err_irq:
 290         vfio_platform_regions_cleanup(vdev);
 291 err_reg:
 292         mutex_unlock(&driver_lock);
 293         module_put(THIS_MODULE);
 294         return ret;
 295 }
 296
 297 static long vfio_platform_ioctl(void *device_data,
 298                                 unsigned int cmd, unsigned long arg)
 299 {
 300         struct vfio_platform_device *vdev = device_data;
 301         unsigned long minsz;
 302
 303         if (cmd == VFIO_DEVICE_GET_INFO) {
 304                 struct vfio_device_info info;
 305
 306                 minsz = offsetofend(struct vfio_device_info, num_irqs);
 307
 308                 if (copy_from_user(&info, (void __user *)arg, minsz))
 309                         return -EFAULT;
 310
 311                 if (info.argsz < minsz)
 312                         return -EINVAL;
 313
 314                 if (vfio_platform_has_reset(vdev))
 315                         vdev->flags |= VFIO_DEVICE_FLAGS_RESET;
 316                 info.flags = vdev->flags;
 317                 info.num_regions = vdev->num_regions;
 318                 info.num_irqs = vdev->num_irqs;
 319
 320                 return copy_to_user((void __user *)arg, &info, minsz) ?
 321                         -EFAULT : 0;
 322
 323         } else if (cmd == VFIO_DEVICE_GET_REGION_INFO) {
 324                 struct vfio_region_info info;
 325
 326                 minsz = offsetofend(struct vfio_region_info, offset);
 327
 328                 if (copy_from_user(&info, (void __user *)arg, minsz))
 329                         return -EFAULT;
 330
 331                 if (info.argsz < minsz)
 332                         return -EINVAL;
 333
 334                 if (info.index >= vdev->num_regions)
 335                         return -EINVAL;
 336
 337                 /* map offset to the physical address  */
 338                 info.offset = VFIO_PLATFORM_INDEX_TO_OFFSET(info.index);
 339                 info.size = vdev->regions[info.index].size;
 340                 info.flags = vdev->regions[info.index].flags;
 341
 342                 return copy_to_user((void __user *)arg, &info, minsz) ?
 343                         -EFAULT : 0;
 344
 345         } else if (cmd == VFIO_DEVICE_GET_IRQ_INFO) {
 346                 struct vfio_irq_info info;
 347
 348                 minsz = offsetofend(struct vfio_irq_info, count);
 349
 350                 if (copy_from_user(&info, (void __user *)arg, minsz))
 351                         return -EFAULT;
 352
 353                 if (info.argsz < minsz)
 354                         return -EINVAL;
 355
 356                 if (info.index >= vdev->num_irqs)
 357                         return -EINVAL;
 358
 359                 info.flags = vdev->irqs[info.index].flags;
 360                 info.count = vdev->irqs[info.index].count;
 361
 362                 return copy_to_user((void __user *)arg, &info, minsz) ?
 363                         -EFAULT : 0;
 364
 365         } else if (cmd == VFIO_DEVICE_SET_IRQS) {
 366                 struct vfio_irq_set hdr;
 367                 u8 *data = NULL;
 368                 int ret = 0;
 369                 size_t data_size = 0;
 370
 371                 minsz = offsetofend(struct vfio_irq_set, count);
 372
 373                 if (copy_from_user(&hdr, (void __user *)arg, minsz))
 374                         return -EFAULT;
 375
 376                 ret = vfio_set_irqs_validate_and_prepare(&hdr, vdev->num_irqs,
 377                                                  vdev->num_irqs, &data_size);
 378                 if (ret)
 379                         return ret;
 380
 381                 if (data_size) {
 382                         data = memdup_user((void __user *)(arg + minsz),
 383                                             data_size);
 384                         if (IS_ERR(data))
 385                                 return PTR_ERR(data);
 386                 }
 387
 388                 mutex_lock(&vdev->igate);
 389
 390                 ret = vfio_platform_set_irqs_ioctl(vdev, hdr.flags, hdr.index,
 391                                                    hdr.start, hdr.count, data);
 392                 mutex_unlock(&vdev->igate);
 393                 kfree(data);
 394
 395                 return ret;
 396
 397         } else if (cmd == VFIO_DEVICE_RESET) {
 398                 return vfio_platform_call_reset(vdev, NULL);
 399         }
 400
 401         return -ENOTTY;
 402 }
 403
 404 static ssize_t vfio_platform_read_mmio(struct vfio_platform_region *reg,
 405                                        char __user *buf, size_t count,
 406                                        loff_t off)
 407 {
 408         unsigned int done = 0;
 409
 410         if (!reg->ioaddr) {
 411                 reg->ioaddr =
 412                         ioremap(reg->addr, reg->size);
 413
 414                 if (!reg->ioaddr)
 415                         return -ENOMEM;
 416         }
 417
 418         while (count) {
 419                 size_t filled;
 420
 421                 if (count >= 4 && !(off % 4)) {
 422                         u32 val;
 423
 424                         val = ioread32(reg->ioaddr + off);
 425                         if (copy_to_user(buf, &val, 4))
 426                                 goto err;
 427
 428                         filled = 4;
 429                 } else if (count >= 2 && !(off % 2)) {
 430                         u16 val;
 431
 432                         val = ioread16(reg->ioaddr + off);
 433                         if (copy_to_user(buf, &val, 2))
 434                                 goto err;
 435
 436                         filled = 2;
 437                 } else {
 438                         u8 val;
 439
 440                         val = ioread8(reg->ioaddr + off);
 441                         if (copy_to_user(buf, &val, 1))
 442                                 goto err;
 443
 444                         filled = 1;
 445                 }
 446
 447
 448                 count -= filled;
 449                 done += filled;
 450                 off += filled;
 451                 buf += filled;
 452         }
 453
 454         return done;
 455 err:
 456         return -EFAULT;
 457 }
 458
 459 static ssize_t vfio_platform_read(void *device_data, char __user *buf,
 460                                   size_t count, loff_t *ppos)
 461 {
 462         struct vfio_platform_device *vdev = device_data;
 463         unsigned int index = VFIO_PLATFORM_OFFSET_TO_INDEX(*ppos);
 464         loff_t off = *ppos & VFIO_PLATFORM_OFFSET_MASK;
 465
 466         if (index >= vdev->num_regions)
 467                 return -EINVAL;
 468
 469         if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_READ))
 470                 return -EINVAL;
 471
 472         if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_MMIO)
 473                 return vfio_platform_read_mmio(&vdev->regions[index],
 474                                                         buf, count, off);
 475         else if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_PIO)
 476                 return -EINVAL; /* not implemented */
 477
 478         return -EINVAL;
 479 }
 480
 481 static ssize_t vfio_platform_write_mmio(struct vfio_platform_region *reg,
 482                                         const char __user *buf, size_t count,
 483                                         loff_t off)
 484 {
 485         unsigned int done = 0;
 486
 487         if (!reg->ioaddr) {
 488                 reg->ioaddr =
 489                         ioremap(reg->addr, reg->size);
 490
 491                 if (!reg->ioaddr)
 492                         return -ENOMEM;
 493         }
 494
 495         while (count) {
 496                 size_t filled;
 497
 498                 if (count >= 4 && !(off % 4)) {
 499                         u32 val;
 500
 501                         if (copy_from_user(&val, buf, 4))
 502                                 goto err;
 503                         iowrite32(val, reg->ioaddr + off);
 504
 505                         filled = 4;
 506                 } else if (count >= 2 && !(off % 2)) {
 507                         u16 val;
 508
 509                         if (copy_from_user(&val, buf, 2))
 510                                 goto err;
 511                         iowrite16(val, reg->ioaddr + off);
 512
 513                         filled = 2;
 514                 } else {
 515                         u8 val;
 516
 517                         if (copy_from_user(&val, buf, 1))
 518                                 goto err;
 519                         iowrite8(val, reg->ioaddr + off);
 520
 521                         filled = 1;
 522                 }
 523
 524                 count -= filled;
 525                 done += filled;
 526                 off += filled;
 527                 buf += filled;
 528         }
 529
 530         return done;
 531 err:
 532         return -EFAULT;
 533 }
 534
 535 static ssize_t vfio_platform_write(void *device_data, const char __user *buf,
 536                                    size_t count, loff_t *ppos)
 537 {
 538         struct vfio_platform_device *vdev = device_data;
 539         unsigned int index = VFIO_PLATFORM_OFFSET_TO_INDEX(*ppos);
 540         loff_t off = *ppos & VFIO_PLATFORM_OFFSET_MASK;
 541
 542         if (index >= vdev->num_regions)
 543                 return -EINVAL;
 544
 545         if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_WRITE))
 546                 return -EINVAL;
 547
 548         if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_MMIO)
 549                 return vfio_platform_write_mmio(&vdev->regions[index],
 550                                                         buf, count, off);
 551         else if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_PIO)
 552                 return -EINVAL; /* not implemented */
 553
 554         return -EINVAL;
 555 }
 556
 557 static int vfio_platform_mmap_mmio(struct vfio_platform_region region,
 558                                    struct vm_area_struct *vma)
 559 {
 560         u64 req_len, pgoff, req_start;
 561
 562         req_len = vma->vm_end - vma->vm_start;
 563         pgoff = vma->vm_pgoff &
 564                 ((1U << (VFIO_PLATFORM_OFFSET_SHIFT - PAGE_SHIFT)) - 1);
 565         req_start = pgoff << PAGE_SHIFT;
 566
 567         if (region.size < PAGE_SIZE || req_start + req_len > region.size)
 568                 return -EINVAL;
 569
 570         vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
 571         vma->vm_pgoff = (region.addr >> PAGE_SHIFT) + pgoff;
 572
 573         return remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
 574                                req_len, vma->vm_page_prot);
 575 }
 576
 577 static int vfio_platform_mmap(void *device_data, struct vm_area_struct *vma)
 578 {
 579         struct vfio_platform_device *vdev = device_data;
 580         unsigned int index;
 581
 582         index = vma->vm_pgoff >> (VFIO_PLATFORM_OFFSET_SHIFT - PAGE_SHIFT);
 583
 584         if (vma->vm_end < vma->vm_start)
 585                 return -EINVAL;
 586         if (!(vma->vm_flags & VM_SHARED))
 587                 return -EINVAL;
 588         if (index >= vdev->num_regions)
 589                 return -EINVAL;
 590         if (vma->vm_start & ~PAGE_MASK)
 591                 return -EINVAL;
 592         if (vma->vm_end & ~PAGE_MASK)
 593                 return -EINVAL;
 594
 595         if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_MMAP))
 596                 return -EINVAL;
 597
 598         if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_READ)
 599                         && (vma->vm_flags & VM_READ))
 600                 return -EINVAL;
 601
 602         if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_WRITE)
 603                         && (vma->vm_flags & VM_WRITE))
 604                 return -EINVAL;
 605
 606         vma->vm_private_data = vdev;
 607
 608         if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_MMIO)
 609                 return vfio_platform_mmap_mmio(vdev->regions[index], vma);
 610
 611         else if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_PIO)
 612                 return -EINVAL; /* not implemented */
 613
 614         return -EINVAL;
 615 }
 616
 617 static const struct vfio_device_ops vfio_platform_ops = {
 618         .name           = "vfio-platform",
 619         .open           = vfio_platform_open,
 620         .release        = vfio_platform_release,
 621         .ioctl          = vfio_platform_ioctl,
 622         .read           = vfio_platform_read,
 623         .write          = vfio_platform_write,
 624         .mmap           = vfio_platform_mmap,
 625 };
 626
 627 static int vfio_platform_of_probe(struct vfio_platform_device *vdev,
 628                            struct device *dev)
 629 {
 630         int ret;
 631
 632         ret = device_property_read_string(dev, "compatible",
 633                                           &vdev->compat);
 634         if (ret)
 635                 dev_err(dev, "Cannot retrieve compat for %s\n", vdev->name);
 636
 637         return ret;
 638 }
 639
 640 /*
 641  * There can be two kernel build combinations. One build where
 642  * ACPI is not selected in Kconfig and another one with the ACPI Kconfig.
 643  *
 644  * In the first case, vfio_platform_acpi_probe will return since
 645  * acpi_disabled is 1. DT user will not see any kind of messages from
 646  * ACPI.
 647  *
 648  * In the second case, both DT and ACPI is compiled in but the system is
 649  * booting with any of these combinations.
 650  *
 651  * If the firmware is DT type, then acpi_disabled is 1. The ACPI probe routine
 652  * terminates immediately without any messages.
 653  *
 654  * If the firmware is ACPI type, then acpi_disabled is 0. All other checks are
 655  * valid checks. We cannot claim that this system is DT.
 656  */
 657 int vfio_platform_probe_common(struct vfio_platform_device *vdev,
 658                                struct device *dev)
 659 {
 660         struct iommu_group *group;
 661         int ret;
 662
 663         if (!vdev)
 664                 return -EINVAL;
 665
 666         ret = vfio_platform_acpi_probe(vdev, dev);
 667         if (ret)
 668                 ret = vfio_platform_of_probe(vdev, dev);
 669
 670         if (ret)
 671                 return ret;
 672
 673         vdev->device = dev;
 674
 675         ret = vfio_platform_get_reset(vdev);
 676         if (ret && vdev->reset_required) {
 677                 dev_err(dev, "No reset function found for device %s\n",
 678                         vdev->name);
 679                 return ret;
 680         }
 681
 682         group = vfio_iommu_group_get(dev);
 683         if (!group) {
 684                 dev_err(dev, "No IOMMU group for device %s\n", vdev->name);
 685                 ret = -EINVAL;
 686                 goto put_reset;
 687         }
 688
 689         ret = vfio_add_group_dev(dev, &vfio_platform_ops, vdev);
 690         if (ret)
 691                 goto put_iommu;
 692
 693         mutex_init(&vdev->igate);
 694
 695         pm_runtime_enable(vdev->device);
 696         return 0;
 697
 698 put_iommu:
 699         vfio_iommu_group_put(group, dev);
 700 put_reset:
 701         vfio_platform_put_reset(vdev);
 702         return ret;
 703 }
 704 EXPORT_SYMBOL_GPL(vfio_platform_probe_common);
 705
 706 struct vfio_platform_device *vfio_platform_remove_common(struct device *dev)
 707 {
 708         struct vfio_platform_device *vdev;
 709
 710         vdev = vfio_del_group_dev(dev);
 711
 712         if (vdev) {
 713                 pm_runtime_disable(vdev->device);
 714                 vfio_platform_put_reset(vdev);
 715                 vfio_iommu_group_put(dev->iommu_group, dev);
 716         }
 717
 718         return vdev;
 719 }
 720 EXPORT_SYMBOL_GPL(vfio_platform_remove_common);
 721
 722 void __vfio_platform_register_reset(struct vfio_platform_reset_node *node)
 723 {
 724         mutex_lock(&driver_lock);
 725         list_add(&node->link, &reset_list);
 726         mutex_unlock(&driver_lock);
 727 }
 728 EXPORT_SYMBOL_GPL(__vfio_platform_register_reset);
 729
 730 void vfio_platform_unregister_reset(const char *compat,
 731                                     vfio_platform_reset_fn_t fn)
 732 {
 733         struct vfio_platform_reset_node *iter, *temp;
 734
 735         mutex_lock(&driver_lock);
 736         list_for_each_entry_safe(iter, temp, &reset_list, link) {
 737                 if (!strcmp(iter->compat, compat) && (iter->of_reset == fn)) {
 738                         list_del(&iter->link);
 739                         break;
 740                 }
 741         }
 742
 743         mutex_unlock(&driver_lock);
 744
 745 }
 746 EXPORT_SYMBOL_GPL(vfio_platform_unregister_reset);
 747
 748 MODULE_VERSION(DRIVER_VERSION);
 749 MODULE_LICENSE("GPL v2");
 750 MODULE_AUTHOR(DRIVER_AUTHOR);
 751 MODULE_DESCRIPTION(DRIVER_DESC);