drivers/vfio/platform/vfio_platform_common.c

   1 /*
   2  * Copyright (C) 2013 - Virtual Open Systems
   3  * Author: Antonios Motakis <a.motakis@virtualopensystems.com>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License, version 2, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  */
  14
  15 #include <linux/device.h>
  16 #include <linux/acpi.h>
  17 #include <linux/iommu.h>
  18 #include <linux/module.h>
  19 #include <linux/mutex.h>
  20 #include <linux/pm_runtime.h>
  21 #include <linux/slab.h>
  22 #include <linux/types.h>
  23 #include <linux/uaccess.h>
  24 #include <linux/vfio.h>
  25
  26 #include "vfio_platform_private.h"
  27
  28 #define DRIVER_VERSION  "0.10"
  29 #define DRIVER_AUTHOR   "Antonios Motakis <a.motakis@virtualopensystems.com>"
  30 #define DRIVER_DESC     "VFIO platform base module"
  31
  32 #define VFIO_PLATFORM_IS_ACPI(vdev) ((vdev)->acpihid != NULL)
  33
  34 static LIST_HEAD(reset_list);
  35 static DEFINE_MUTEX(driver_lock);
  36
  37 static vfio_platform_reset_fn_t vfio_platform_lookup_reset(const char *compat,
  38                                         struct module **module)
  39 {
  40         struct vfio_platform_reset_node *iter;
  41         vfio_platform_reset_fn_t reset_fn = NULL;
  42
  43         mutex_lock(&driver_lock);
  44         list_for_each_entry(iter, &reset_list, link) {
  45                 if (!strcmp(iter->compat, compat) &&
  46                         try_module_get(iter->owner)) {
  47                         *module = iter->owner;
  48                         reset_fn = iter->of_reset;
  49                         break;
  50                 }
  51         }
  52         mutex_unlock(&driver_lock);
  53         return reset_fn;
  54 }
  55
  56 static int vfio_platform_acpi_probe(struct vfio_platform_device *vdev,
  57                                     struct device *dev)
  58 {
  59         struct acpi_device *adev;
  60
  61         if (acpi_disabled)
  62                 return -ENOENT;
  63
  64         adev = ACPI_COMPANION(dev);
  65         if (!adev) {
  66                 pr_err("VFIO: ACPI companion device not found for %s\n",
  67                         vdev->name);
  68                 return -ENODEV;
  69         }
  70
  71 #ifdef CONFIG_ACPI
  72         vdev->acpihid = acpi_device_hid(adev);
  73 #endif
  74         return WARN_ON(!vdev->acpihid) ? -EINVAL : 0;
  75 }
  76
  77 static int vfio_platform_acpi_call_reset(struct vfio_platform_device *vdev,
  78                                   const char **extra_dbg)
  79 {
  80 #ifdef CONFIG_ACPI
  81         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
  82         struct device *dev = vdev->device;
  83         acpi_handle handle = ACPI_HANDLE(dev);
  84         acpi_status acpi_ret;
  85
  86         acpi_ret = acpi_evaluate_object(handle, "_RST", NULL, &buffer);
  87         if (ACPI_FAILURE(acpi_ret)) {
  88                 if (extra_dbg)
  89                         *extra_dbg = acpi_format_exception(acpi_ret);
  90                 return -EINVAL;
  91         }
  92
  93         return 0;
  94 #else
  95         return -ENOENT;
  96 #endif
  97 }
  98
  99 static bool vfio_platform_acpi_has_reset(struct vfio_platform_device *vdev)
 100 {
 101 #ifdef CONFIG_ACPI
 102         struct device *dev = vdev->device;
 103         acpi_handle handle = ACPI_HANDLE(dev);
 104
 105         return acpi_has_method(handle, "_RST");
 106 #else
 107         return false;
 108 #endif
 109 }
 110
 111 static bool vfio_platform_has_reset(struct vfio_platform_device *vdev)
 112 {
 113         if (VFIO_PLATFORM_IS_ACPI(vdev))
 114                 return vfio_platform_acpi_has_reset(vdev);
 115
 116         return vdev->of_reset ? true : false;
 117 }
 118
 119 static int vfio_platform_get_reset(struct vfio_platform_device *vdev)
 120 {
 121         if (VFIO_PLATFORM_IS_ACPI(vdev))
 122                 return vfio_platform_acpi_has_reset(vdev) ? 0 : -ENOENT;
 123
 124         vdev->of_reset = vfio_platform_lookup_reset(vdev->compat,
 125                                                     &vdev->reset_module);
 126         if (!vdev->of_reset) {
 127                 request_module("vfio-reset:%s", vdev->compat);
 128                 vdev->of_reset = vfio_platform_lookup_reset(vdev->compat,
 129                                                         &vdev->reset_module);
 130         }
 131
 132         return vdev->of_reset ? 0 : -ENOENT;
 133 }
 134
 135 static void vfio_platform_put_reset(struct vfio_platform_device *vdev)
 136 {
 137         if (VFIO_PLATFORM_IS_ACPI(vdev))
 138                 return;
 139
 140         if (vdev->of_reset)
 141                 module_put(vdev->reset_module);
 142 }
 143
 144 static int vfio_platform_regions_init(struct vfio_platform_device *vdev)
 145 {
 146         int cnt = 0, i;
 147
 148         while (vdev->get_resource(vdev, cnt))
 149                 cnt++;
 150
 151         vdev->regions = kcalloc(cnt, sizeof(struct vfio_platform_region),
 152                                 GFP_KERNEL);
 153         if (!vdev->regions)
 154                 return -ENOMEM;
 155
 156         for (i = 0; i < cnt;  i++) {
 157                 struct resource *res =
 158                         vdev->get_resource(vdev, i);
 159
 160                 if (!res)
 161                         goto err;
 162
 163                 vdev->regions[i].addr = res->start;
 164                 vdev->regions[i].size = resource_size(res);
 165                 vdev->regions[i].flags = 0;
 166
 167                 switch (resource_type(res)) {
 168                 case IORESOURCE_MEM:
 169                         vdev->regions[i].type = VFIO_PLATFORM_REGION_TYPE_MMIO;
 170                         vdev->regions[i].flags |= VFIO_REGION_INFO_FLAG_READ;
 171                         if (!(res->flags & IORESOURCE_READONLY))
 172                                 vdev->regions[i].flags |=
 173                                         VFIO_REGION_INFO_FLAG_WRITE;
 174
 175                         /*
 176                          * Only regions addressed with PAGE granularity may be
 177                          * MMAPed securely.
 178                          */
 179                         if (!(vdev->regions[i].addr & ~PAGE_MASK) &&
 180                                         !(vdev->regions[i].size & ~PAGE_MASK))
 181                                 vdev->regions[i].flags |=
 182                                         VFIO_REGION_INFO_FLAG_MMAP;
 183
 184                         break;
 185                 case IORESOURCE_IO:
 186                         vdev->regions[i].type = VFIO_PLATFORM_REGION_TYPE_PIO;
 187                         break;
 188                 default:
 189                         goto err;
 190                 }
 191         }
 192
 193         vdev->num_regions = cnt;
 194
 195         return 0;
 196 err:
 197         kfree(vdev->regions);
 198         return -EINVAL;
 199 }
 200
 201 static void vfio_platform_regions_cleanup(struct vfio_platform_device *vdev)
 202 {
 203         int i;
 204
 205         for (i = 0; i < vdev->num_regions; i++)
 206                 iounmap(vdev->regions[i].ioaddr);
 207
 208         vdev->num_regions = 0;
 209         kfree(vdev->regions);
 210 }
 211
 212 static int vfio_platform_call_reset(struct vfio_platform_device *vdev,
 213                                     const char **extra_dbg)
 214 {
 215         if (VFIO_PLATFORM_IS_ACPI(vdev)) {
 216                 dev_info(vdev->device, "reset\n");
 217                 return vfio_platform_acpi_call_reset(vdev, extra_dbg);
 218         } else if (vdev->of_reset) {
 219                 dev_info(vdev->device, "reset\n");
 220                 return vdev->of_reset(vdev);
 221         }
 222
 223         dev_warn(vdev->device, "no reset function found!\n");
 224         return -EINVAL;
 225 }
 226
 227 static void vfio_platform_release(void *device_data)
 228 {
 229         struct vfio_platform_device *vdev = device_data;
 230
 231         mutex_lock(&driver_lock);
 232
 233         if (!(--vdev->refcnt)) {
 234                 const char *extra_dbg = NULL;
 235                 int ret;
 236
 237                 ret = vfio_platform_call_reset(vdev, &extra_dbg);
 238                 if (ret && vdev->reset_required) {
 239                         dev_warn(vdev->device, "reset driver is required and reset call failed in release (%d) %s\n",
 240                                  ret, extra_dbg ? extra_dbg : "");
 241                         WARN_ON(1);
 242                 }
 243                 pm_runtime_put(vdev->device);
 244                 vfio_platform_regions_cleanup(vdev);
 245                 vfio_platform_irq_cleanup(vdev);
 246         }
 247
 248         mutex_unlock(&driver_lock);
 249
 250         module_put(vdev->parent_module);
 251 }
 252
 253 static int vfio_platform_open(void *device_data)
 254 {
 255         struct vfio_platform_device *vdev = device_data;
 256         int ret;
 257
 258         if (!try_module_get(vdev->parent_module))
 259                 return -ENODEV;
 260
 261         mutex_lock(&driver_lock);
 262
 263         if (!vdev->refcnt) {
 264                 const char *extra_dbg = NULL;
 265
 266                 ret = vfio_platform_regions_init(vdev);
 267                 if (ret)
 268                         goto err_reg;
 269
 270                 ret = vfio_platform_irq_init(vdev);
 271                 if (ret)
 272                         goto err_irq;
 273
 274                 ret = pm_runtime_get_sync(vdev->device);
 275                 if (ret < 0)
 276                         goto err_rst;
 277
 278                 ret = vfio_platform_call_reset(vdev, &extra_dbg);
 279                 if (ret && vdev->reset_required) {
 280                         dev_warn(vdev->device, "reset driver is required and reset call failed in open (%d) %s\n",
 281                                  ret, extra_dbg ? extra_dbg : "");
 282                         goto err_rst;
 283                 }
 284         }
 285
 286         vdev->refcnt++;
 287
 288         mutex_unlock(&driver_lock);
 289         return 0;
 290
 291 err_rst:
 292         pm_runtime_put(vdev->device);
 293         vfio_platform_irq_cleanup(vdev);
 294 err_irq:
 295         vfio_platform_regions_cleanup(vdev);
 296 err_reg:
 297         mutex_unlock(&driver_lock);
 298         module_put(vdev->parent_module);
 299         return ret;
 300 }
 301
 302 static long vfio_platform_ioctl(void *device_data,
 303                                 unsigned int cmd, unsigned long arg)
 304 {
 305         struct vfio_platform_device *vdev = device_data;
 306         unsigned long minsz;
 307
 308         if (cmd == VFIO_DEVICE_GET_INFO) {
 309                 struct vfio_device_info info;
 310
 311                 minsz = offsetofend(struct vfio_device_info, num_irqs);
 312
 313                 if (copy_from_user(&info, (void __user *)arg, minsz))
 314                         return -EFAULT;
 315
 316                 if (info.argsz < minsz)
 317                         return -EINVAL;
 318
 319                 if (vfio_platform_has_reset(vdev))
 320                         vdev->flags |= VFIO_DEVICE_FLAGS_RESET;
 321                 info.flags = vdev->flags;
 322                 info.num_regions = vdev->num_regions;
 323                 info.num_irqs = vdev->num_irqs;
 324
 325                 return copy_to_user((void __user *)arg, &info, minsz) ?
 326                         -EFAULT : 0;
 327
 328         } else if (cmd == VFIO_DEVICE_GET_REGION_INFO) {
 329                 struct vfio_region_info info;
 330
 331                 minsz = offsetofend(struct vfio_region_info, offset);
 332
 333                 if (copy_from_user(&info, (void __user *)arg, minsz))
 334                         return -EFAULT;
 335
 336                 if (info.argsz < minsz)
 337                         return -EINVAL;
 338
 339                 if (info.index >= vdev->num_regions)
 340                         return -EINVAL;
 341
 342                 /* map offset to the physical address  */
 343                 info.offset = VFIO_PLATFORM_INDEX_TO_OFFSET(info.index);
 344                 info.size = vdev->regions[info.index].size;
 345                 info.flags = vdev->regions[info.index].flags;
 346
 347                 return copy_to_user((void __user *)arg, &info, minsz) ?
 348                         -EFAULT : 0;
 349
 350         } else if (cmd == VFIO_DEVICE_GET_IRQ_INFO) {
 351                 struct vfio_irq_info info;
 352
 353                 minsz = offsetofend(struct vfio_irq_info, count);
 354
 355                 if (copy_from_user(&info, (void __user *)arg, minsz))
 356                         return -EFAULT;
 357
 358                 if (info.argsz < minsz)
 359                         return -EINVAL;
 360
 361                 if (info.index >= vdev->num_irqs)
 362                         return -EINVAL;
 363
 364                 info.flags = vdev->irqs[info.index].flags;
 365                 info.count = vdev->irqs[info.index].count;
 366
 367                 return copy_to_user((void __user *)arg, &info, minsz) ?
 368                         -EFAULT : 0;
 369
 370         } else if (cmd == VFIO_DEVICE_SET_IRQS) {
 371                 struct vfio_irq_set hdr;
 372                 u8 *data = NULL;
 373                 int ret = 0;
 374                 size_t data_size = 0;
 375
 376                 minsz = offsetofend(struct vfio_irq_set, count);
 377
 378                 if (copy_from_user(&hdr, (void __user *)arg, minsz))
 379                         return -EFAULT;
 380
 381                 ret = vfio_set_irqs_validate_and_prepare(&hdr, vdev->num_irqs,
 382                                                  vdev->num_irqs, &data_size);
 383                 if (ret)
 384                         return ret;
 385
 386                 if (data_size) {
 387                         data = memdup_user((void __user *)(arg + minsz),
 388                                             data_size);
 389                         if (IS_ERR(data))
 390                                 return PTR_ERR(data);
 391                 }
 392
 393                 mutex_lock(&vdev->igate);
 394
 395                 ret = vfio_platform_set_irqs_ioctl(vdev, hdr.flags, hdr.index,
 396                                                    hdr.start, hdr.count, data);
 397                 mutex_unlock(&vdev->igate);
 398                 kfree(data);
 399
 400                 return ret;
 401
 402         } else if (cmd == VFIO_DEVICE_RESET) {
 403                 return vfio_platform_call_reset(vdev, NULL);
 404         }
 405
 406         return -ENOTTY;
 407 }
 408
 409 static ssize_t vfio_platform_read_mmio(struct vfio_platform_region *reg,
 410                                        char __user *buf, size_t count,
 411                                        loff_t off)
 412 {
 413         unsigned int done = 0;
 414
 415         if (!reg->ioaddr) {
 416                 reg->ioaddr =
 417                         ioremap_nocache(reg->addr, reg->size);
 418
 419                 if (!reg->ioaddr)
 420                         return -ENOMEM;
 421         }
 422
 423         while (count) {
 424                 size_t filled;
 425
 426                 if (count >= 4 && !(off % 4)) {
 427                         u32 val;
 428
 429                         val = ioread32(reg->ioaddr + off);
 430                         if (copy_to_user(buf, &val, 4))
 431                                 goto err;
 432
 433                         filled = 4;
 434                 } else if (count >= 2 && !(off % 2)) {
 435                         u16 val;
 436
 437                         val = ioread16(reg->ioaddr + off);
 438                         if (copy_to_user(buf, &val, 2))
 439                                 goto err;
 440
 441                         filled = 2;
 442                 } else {
 443                         u8 val;
 444
 445                         val = ioread8(reg->ioaddr + off);
 446                         if (copy_to_user(buf, &val, 1))
 447                                 goto err;
 448
 449                         filled = 1;
 450                 }
 451
 452
 453                 count -= filled;
 454                 done += filled;
 455                 off += filled;
 456                 buf += filled;
 457         }
 458
 459         return done;
 460 err:
 461         return -EFAULT;
 462 }
 463
 464 static ssize_t vfio_platform_read(void *device_data, char __user *buf,
 465                                   size_t count, loff_t *ppos)
 466 {
 467         struct vfio_platform_device *vdev = device_data;
 468         unsigned int index = VFIO_PLATFORM_OFFSET_TO_INDEX(*ppos);
 469         loff_t off = *ppos & VFIO_PLATFORM_OFFSET_MASK;
 470
 471         if (index >= vdev->num_regions)
 472                 return -EINVAL;
 473
 474         if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_READ))
 475                 return -EINVAL;
 476
 477         if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_MMIO)
 478                 return vfio_platform_read_mmio(&vdev->regions[index],
 479                                                         buf, count, off);
 480         else if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_PIO)
 481                 return -EINVAL; /* not implemented */
 482
 483         return -EINVAL;
 484 }
 485
 486 static ssize_t vfio_platform_write_mmio(struct vfio_platform_region *reg,
 487                                         const char __user *buf, size_t count,
 488                                         loff_t off)
 489 {
 490         unsigned int done = 0;
 491
 492         if (!reg->ioaddr) {
 493                 reg->ioaddr =
 494                         ioremap_nocache(reg->addr, reg->size);
 495
 496                 if (!reg->ioaddr)
 497                         return -ENOMEM;
 498         }
 499
 500         while (count) {
 501                 size_t filled;
 502
 503                 if (count >= 4 && !(off % 4)) {
 504                         u32 val;
 505
 506                         if (copy_from_user(&val, buf, 4))
 507                                 goto err;
 508                         iowrite32(val, reg->ioaddr + off);
 509
 510                         filled = 4;
 511                 } else if (count >= 2 && !(off % 2)) {
 512                         u16 val;
 513
 514                         if (copy_from_user(&val, buf, 2))
 515                                 goto err;
 516                         iowrite16(val, reg->ioaddr + off);
 517
 518                         filled = 2;
 519                 } else {
 520                         u8 val;
 521
 522                         if (copy_from_user(&val, buf, 1))
 523                                 goto err;
 524                         iowrite8(val, reg->ioaddr + off);
 525
 526                         filled = 1;
 527                 }
 528
 529                 count -= filled;
 530                 done += filled;
 531                 off += filled;
 532                 buf += filled;
 533         }
 534
 535         return done;
 536 err:
 537         return -EFAULT;
 538 }
 539
 540 static ssize_t vfio_platform_write(void *device_data, const char __user *buf,
 541                                    size_t count, loff_t *ppos)
 542 {
 543         struct vfio_platform_device *vdev = device_data;
 544         unsigned int index = VFIO_PLATFORM_OFFSET_TO_INDEX(*ppos);
 545         loff_t off = *ppos & VFIO_PLATFORM_OFFSET_MASK;
 546
 547         if (index >= vdev->num_regions)
 548                 return -EINVAL;
 549
 550         if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_WRITE))
 551                 return -EINVAL;
 552
 553         if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_MMIO)
 554                 return vfio_platform_write_mmio(&vdev->regions[index],
 555                                                         buf, count, off);
 556         else if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_PIO)
 557                 return -EINVAL; /* not implemented */
 558
 559         return -EINVAL;
 560 }
 561
 562 static int vfio_platform_mmap_mmio(struct vfio_platform_region region,
 563                                    struct vm_area_struct *vma)
 564 {
 565         u64 req_len, pgoff, req_start;
 566
 567         req_len = vma->vm_end - vma->vm_start;
 568         pgoff = vma->vm_pgoff &
 569                 ((1U << (VFIO_PLATFORM_OFFSET_SHIFT - PAGE_SHIFT)) - 1);
 570         req_start = pgoff << PAGE_SHIFT;
 571
 572         if (region.size < PAGE_SIZE || req_start + req_len > region.size)
 573                 return -EINVAL;
 574
 575         vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
 576         vma->vm_pgoff = (region.addr >> PAGE_SHIFT) + pgoff;
 577
 578         return remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
 579                                req_len, vma->vm_page_prot);
 580 }
 581
 582 static int vfio_platform_mmap(void *device_data, struct vm_area_struct *vma)
 583 {
 584         struct vfio_platform_device *vdev = device_data;
 585         unsigned int index;
 586
 587         index = vma->vm_pgoff >> (VFIO_PLATFORM_OFFSET_SHIFT - PAGE_SHIFT);
 588
 589         if (vma->vm_end < vma->vm_start)
 590                 return -EINVAL;
 591         if (!(vma->vm_flags & VM_SHARED))
 592                 return -EINVAL;
 593         if (index >= vdev->num_regions)
 594                 return -EINVAL;
 595         if (vma->vm_start & ~PAGE_MASK)
 596                 return -EINVAL;
 597         if (vma->vm_end & ~PAGE_MASK)
 598                 return -EINVAL;
 599
 600         if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_MMAP))
 601                 return -EINVAL;
 602
 603         if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_READ)
 604                         && (vma->vm_flags & VM_READ))
 605                 return -EINVAL;
 606
 607         if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_WRITE)
 608                         && (vma->vm_flags & VM_WRITE))
 609                 return -EINVAL;
 610
 611         vma->vm_private_data = vdev;
 612
 613         if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_MMIO)
 614                 return vfio_platform_mmap_mmio(vdev->regions[index], vma);
 615
 616         else if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_PIO)
 617                 return -EINVAL; /* not implemented */
 618
 619         return -EINVAL;
 620 }
 621
 622 static const struct vfio_device_ops vfio_platform_ops = {
 623         .name           = "vfio-platform",
 624         .open           = vfio_platform_open,
 625         .release        = vfio_platform_release,
 626         .ioctl          = vfio_platform_ioctl,
 627         .read           = vfio_platform_read,
 628         .write          = vfio_platform_write,
 629         .mmap           = vfio_platform_mmap,
 630 };
 631
 632 static int vfio_platform_of_probe(struct vfio_platform_device *vdev,
 633                            struct device *dev)
 634 {
 635         int ret;
 636
 637         ret = device_property_read_string(dev, "compatible",
 638                                           &vdev->compat);
 639         if (ret)
 640                 pr_err("VFIO: Cannot retrieve compat for %s\n", vdev->name);
 641
 642         return ret;
 643 }
 644
 645 /*
 646  * There can be two kernel build combinations. One build where
 647  * ACPI is not selected in Kconfig and another one with the ACPI Kconfig.
 648  *
 649  * In the first case, vfio_platform_acpi_probe will return since
 650  * acpi_disabled is 1. DT user will not see any kind of messages from
 651  * ACPI.
 652  *
 653  * In the second case, both DT and ACPI is compiled in but the system is
 654  * booting with any of these combinations.
 655  *
 656  * If the firmware is DT type, then acpi_disabled is 1. The ACPI probe routine
 657  * terminates immediately without any messages.
 658  *
 659  * If the firmware is ACPI type, then acpi_disabled is 0. All other checks are
 660  * valid checks. We cannot claim that this system is DT.
 661  */
 662 int vfio_platform_probe_common(struct vfio_platform_device *vdev,
 663                                struct device *dev)
 664 {
 665         struct iommu_group *group;
 666         int ret;
 667
 668         if (!vdev)
 669                 return -EINVAL;
 670
 671         ret = vfio_platform_acpi_probe(vdev, dev);
 672         if (ret)
 673                 ret = vfio_platform_of_probe(vdev, dev);
 674
 675         if (ret)
 676                 return ret;
 677
 678         vdev->device = dev;
 679
 680         ret = vfio_platform_get_reset(vdev);
 681         if (ret && vdev->reset_required) {
 682                 pr_err("VFIO: No reset function found for device %s\n",
 683                        vdev->name);
 684                 return ret;
 685         }
 686
 687         group = vfio_iommu_group_get(dev);
 688         if (!group) {
 689                 pr_err("VFIO: No IOMMU group for device %s\n", vdev->name);
 690                 ret = -EINVAL;
 691                 goto put_reset;
 692         }
 693
 694         ret = vfio_add_group_dev(dev, &vfio_platform_ops, vdev);
 695         if (ret)
 696                 goto put_iommu;
 697
 698         mutex_init(&vdev->igate);
 699
 700         pm_runtime_enable(vdev->device);
 701         return 0;
 702
 703 put_iommu:
 704         vfio_iommu_group_put(group, dev);
 705 put_reset:
 706         vfio_platform_put_reset(vdev);
 707         return ret;
 708 }
 709 EXPORT_SYMBOL_GPL(vfio_platform_probe_common);
 710
 711 struct vfio_platform_device *vfio_platform_remove_common(struct device *dev)
 712 {
 713         struct vfio_platform_device *vdev;
 714
 715         vdev = vfio_del_group_dev(dev);
 716
 717         if (vdev) {
 718                 pm_runtime_disable(vdev->device);
 719                 vfio_platform_put_reset(vdev);
 720                 vfio_iommu_group_put(dev->iommu_group, dev);
 721         }
 722
 723         return vdev;
 724 }
 725 EXPORT_SYMBOL_GPL(vfio_platform_remove_common);
 726
 727 void __vfio_platform_register_reset(struct vfio_platform_reset_node *node)
 728 {
 729         mutex_lock(&driver_lock);
 730         list_add(&node->link, &reset_list);
 731         mutex_unlock(&driver_lock);
 732 }
 733 EXPORT_SYMBOL_GPL(__vfio_platform_register_reset);
 734
 735 void vfio_platform_unregister_reset(const char *compat,
 736                                     vfio_platform_reset_fn_t fn)
 737 {
 738         struct vfio_platform_reset_node *iter, *temp;
 739
 740         mutex_lock(&driver_lock);
 741         list_for_each_entry_safe(iter, temp, &reset_list, link) {
 742                 if (!strcmp(iter->compat, compat) && (iter->of_reset == fn)) {
 743                         list_del(&iter->link);
 744                         break;
 745                 }
 746         }
 747
 748         mutex_unlock(&driver_lock);
 749
 750 }
 751 EXPORT_SYMBOL_GPL(vfio_platform_unregister_reset);
 752
 753 MODULE_VERSION(DRIVER_VERSION);
 754 MODULE_LICENSE("GPL v2");
 755 MODULE_AUTHOR(DRIVER_AUTHOR);
 756 MODULE_DESCRIPTION(DRIVER_DESC);