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 void vfio_platform_close_device(struct vfio_device *core_vdev)
 222 {
 223         struct vfio_platform_device *vdev =
 224                 container_of(core_vdev, struct vfio_platform_device, vdev);
 225         const char *extra_dbg = NULL;
 226         int ret;
 227
 228         ret = vfio_platform_call_reset(vdev, &extra_dbg);
 229         if (WARN_ON(ret && vdev->reset_required)) {
 230                 dev_warn(
 231                         vdev->device,
 232                         "reset driver is required and reset call failed in release (%d) %s\n",
 233                         ret, extra_dbg ? extra_dbg : "");
 234         }
 235         pm_runtime_put(vdev->device);
 236         vfio_platform_regions_cleanup(vdev);
 237         vfio_platform_irq_cleanup(vdev);
 238 }
 239 EXPORT_SYMBOL_GPL(vfio_platform_close_device);
 240
 241 int vfio_platform_open_device(struct vfio_device *core_vdev)
 242 {
 243         struct vfio_platform_device *vdev =
 244                 container_of(core_vdev, struct vfio_platform_device, vdev);
 245         const char *extra_dbg = NULL;
 246         int ret;
 247
 248         ret = vfio_platform_regions_init(vdev);
 249         if (ret)
 250                 return ret;
 251
 252         ret = vfio_platform_irq_init(vdev);
 253         if (ret)
 254                 goto err_irq;
 255
 256         ret = pm_runtime_get_sync(vdev->device);
 257         if (ret < 0)
 258                 goto err_rst;
 259
 260         ret = vfio_platform_call_reset(vdev, &extra_dbg);
 261         if (ret && vdev->reset_required) {
 262                 dev_warn(
 263                         vdev->device,
 264                         "reset driver is required and reset call failed in open (%d) %s\n",
 265                         ret, extra_dbg ? extra_dbg : "");
 266                 goto err_rst;
 267         }
 268         return 0;
 269
 270 err_rst:
 271         pm_runtime_put(vdev->device);
 272         vfio_platform_irq_cleanup(vdev);
 273 err_irq:
 274         vfio_platform_regions_cleanup(vdev);
 275         return ret;
 276 }
 277 EXPORT_SYMBOL_GPL(vfio_platform_open_device);
 278
 279 long vfio_platform_ioctl(struct vfio_device *core_vdev,
 280                          unsigned int cmd, unsigned long arg)
 281 {
 282         struct vfio_platform_device *vdev =
 283                 container_of(core_vdev, struct vfio_platform_device, vdev);
 284
 285         unsigned long minsz;
 286
 287         if (cmd == VFIO_DEVICE_GET_INFO) {
 288                 struct vfio_device_info info;
 289
 290                 minsz = offsetofend(struct vfio_device_info, num_irqs);
 291
 292                 if (copy_from_user(&info, (void __user *)arg, minsz))
 293                         return -EFAULT;
 294
 295                 if (info.argsz < minsz)
 296                         return -EINVAL;
 297
 298                 if (vfio_platform_has_reset(vdev))
 299                         vdev->flags |= VFIO_DEVICE_FLAGS_RESET;
 300                 info.flags = vdev->flags;
 301                 info.num_regions = vdev->num_regions;
 302                 info.num_irqs = vdev->num_irqs;
 303
 304                 return copy_to_user((void __user *)arg, &info, minsz) ?
 305                         -EFAULT : 0;
 306
 307         } else if (cmd == VFIO_DEVICE_GET_REGION_INFO) {
 308                 struct vfio_region_info info;
 309
 310                 minsz = offsetofend(struct vfio_region_info, offset);
 311
 312                 if (copy_from_user(&info, (void __user *)arg, minsz))
 313                         return -EFAULT;
 314
 315                 if (info.argsz < minsz)
 316                         return -EINVAL;
 317
 318                 if (info.index >= vdev->num_regions)
 319                         return -EINVAL;
 320
 321                 /* map offset to the physical address  */
 322                 info.offset = VFIO_PLATFORM_INDEX_TO_OFFSET(info.index);
 323                 info.size = vdev->regions[info.index].size;
 324                 info.flags = vdev->regions[info.index].flags;
 325
 326                 return copy_to_user((void __user *)arg, &info, minsz) ?
 327                         -EFAULT : 0;
 328
 329         } else if (cmd == VFIO_DEVICE_GET_IRQ_INFO) {
 330                 struct vfio_irq_info info;
 331
 332                 minsz = offsetofend(struct vfio_irq_info, count);
 333
 334                 if (copy_from_user(&info, (void __user *)arg, minsz))
 335                         return -EFAULT;
 336
 337                 if (info.argsz < minsz)
 338                         return -EINVAL;
 339
 340                 if (info.index >= vdev->num_irqs)
 341                         return -EINVAL;
 342
 343                 info.flags = vdev->irqs[info.index].flags;
 344                 info.count = vdev->irqs[info.index].count;
 345
 346                 return copy_to_user((void __user *)arg, &info, minsz) ?
 347                         -EFAULT : 0;
 348
 349         } else if (cmd == VFIO_DEVICE_SET_IRQS) {
 350                 struct vfio_irq_set hdr;
 351                 u8 *data = NULL;
 352                 int ret = 0;
 353                 size_t data_size = 0;
 354
 355                 minsz = offsetofend(struct vfio_irq_set, count);
 356
 357                 if (copy_from_user(&hdr, (void __user *)arg, minsz))
 358                         return -EFAULT;
 359
 360                 ret = vfio_set_irqs_validate_and_prepare(&hdr, vdev->num_irqs,
 361                                                  vdev->num_irqs, &data_size);
 362                 if (ret)
 363                         return ret;
 364
 365                 if (data_size) {
 366                         data = memdup_user((void __user *)(arg + minsz),
 367                                             data_size);
 368                         if (IS_ERR(data))
 369                                 return PTR_ERR(data);
 370                 }
 371
 372                 mutex_lock(&vdev->igate);
 373
 374                 ret = vfio_platform_set_irqs_ioctl(vdev, hdr.flags, hdr.index,
 375                                                    hdr.start, hdr.count, data);
 376                 mutex_unlock(&vdev->igate);
 377                 kfree(data);
 378
 379                 return ret;
 380
 381         } else if (cmd == VFIO_DEVICE_RESET) {
 382                 return vfio_platform_call_reset(vdev, NULL);
 383         }
 384
 385         return -ENOTTY;
 386 }
 387 EXPORT_SYMBOL_GPL(vfio_platform_ioctl);
 388
 389 static ssize_t vfio_platform_read_mmio(struct vfio_platform_region *reg,
 390                                        char __user *buf, size_t count,
 391                                        loff_t off)
 392 {
 393         unsigned int done = 0;
 394
 395         if (!reg->ioaddr) {
 396                 reg->ioaddr =
 397                         ioremap(reg->addr, reg->size);
 398
 399                 if (!reg->ioaddr)
 400                         return -ENOMEM;
 401         }
 402
 403         while (count) {
 404                 size_t filled;
 405
 406                 if (count >= 4 && !(off % 4)) {
 407                         u32 val;
 408
 409                         val = ioread32(reg->ioaddr + off);
 410                         if (copy_to_user(buf, &val, 4))
 411                                 goto err;
 412
 413                         filled = 4;
 414                 } else if (count >= 2 && !(off % 2)) {
 415                         u16 val;
 416
 417                         val = ioread16(reg->ioaddr + off);
 418                         if (copy_to_user(buf, &val, 2))
 419                                 goto err;
 420
 421                         filled = 2;
 422                 } else {
 423                         u8 val;
 424
 425                         val = ioread8(reg->ioaddr + off);
 426                         if (copy_to_user(buf, &val, 1))
 427                                 goto err;
 428
 429                         filled = 1;
 430                 }
 431
 432
 433                 count -= filled;
 434                 done += filled;
 435                 off += filled;
 436                 buf += filled;
 437         }
 438
 439         return done;
 440 err:
 441         return -EFAULT;
 442 }
 443
 444 ssize_t vfio_platform_read(struct vfio_device *core_vdev,
 445                            char __user *buf, size_t count, loff_t *ppos)
 446 {
 447         struct vfio_platform_device *vdev =
 448                 container_of(core_vdev, struct vfio_platform_device, vdev);
 449         unsigned int index = VFIO_PLATFORM_OFFSET_TO_INDEX(*ppos);
 450         loff_t off = *ppos & VFIO_PLATFORM_OFFSET_MASK;
 451
 452         if (index >= vdev->num_regions)
 453                 return -EINVAL;
 454
 455         if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_READ))
 456                 return -EINVAL;
 457
 458         if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_MMIO)
 459                 return vfio_platform_read_mmio(&vdev->regions[index],
 460                                                         buf, count, off);
 461         else if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_PIO)
 462                 return -EINVAL; /* not implemented */
 463
 464         return -EINVAL;
 465 }
 466 EXPORT_SYMBOL_GPL(vfio_platform_read);
 467
 468 static ssize_t vfio_platform_write_mmio(struct vfio_platform_region *reg,
 469                                         const char __user *buf, size_t count,
 470                                         loff_t off)
 471 {
 472         unsigned int done = 0;
 473
 474         if (!reg->ioaddr) {
 475                 reg->ioaddr =
 476                         ioremap(reg->addr, reg->size);
 477
 478                 if (!reg->ioaddr)
 479                         return -ENOMEM;
 480         }
 481
 482         while (count) {
 483                 size_t filled;
 484
 485                 if (count >= 4 && !(off % 4)) {
 486                         u32 val;
 487
 488                         if (copy_from_user(&val, buf, 4))
 489                                 goto err;
 490                         iowrite32(val, reg->ioaddr + off);
 491
 492                         filled = 4;
 493                 } else if (count >= 2 && !(off % 2)) {
 494                         u16 val;
 495
 496                         if (copy_from_user(&val, buf, 2))
 497                                 goto err;
 498                         iowrite16(val, reg->ioaddr + off);
 499
 500                         filled = 2;
 501                 } else {
 502                         u8 val;
 503
 504                         if (copy_from_user(&val, buf, 1))
 505                                 goto err;
 506                         iowrite8(val, reg->ioaddr + off);
 507
 508                         filled = 1;
 509                 }
 510
 511                 count -= filled;
 512                 done += filled;
 513                 off += filled;
 514                 buf += filled;
 515         }
 516
 517         return done;
 518 err:
 519         return -EFAULT;
 520 }
 521
 522 ssize_t vfio_platform_write(struct vfio_device *core_vdev, const char __user *buf,
 523                             size_t count, loff_t *ppos)
 524 {
 525         struct vfio_platform_device *vdev =
 526                 container_of(core_vdev, struct vfio_platform_device, vdev);
 527         unsigned int index = VFIO_PLATFORM_OFFSET_TO_INDEX(*ppos);
 528         loff_t off = *ppos & VFIO_PLATFORM_OFFSET_MASK;
 529
 530         if (index >= vdev->num_regions)
 531                 return -EINVAL;
 532
 533         if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_WRITE))
 534                 return -EINVAL;
 535
 536         if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_MMIO)
 537                 return vfio_platform_write_mmio(&vdev->regions[index],
 538                                                         buf, count, off);
 539         else if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_PIO)
 540                 return -EINVAL; /* not implemented */
 541
 542         return -EINVAL;
 543 }
 544 EXPORT_SYMBOL_GPL(vfio_platform_write);
 545
 546 static int vfio_platform_mmap_mmio(struct vfio_platform_region region,
 547                                    struct vm_area_struct *vma)
 548 {
 549         u64 req_len, pgoff, req_start;
 550
 551         req_len = vma->vm_end - vma->vm_start;
 552         pgoff = vma->vm_pgoff &
 553                 ((1U << (VFIO_PLATFORM_OFFSET_SHIFT - PAGE_SHIFT)) - 1);
 554         req_start = pgoff << PAGE_SHIFT;
 555
 556         if (region.size < PAGE_SIZE || req_start + req_len > region.size)
 557                 return -EINVAL;
 558
 559         vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
 560         vma->vm_pgoff = (region.addr >> PAGE_SHIFT) + pgoff;
 561
 562         return remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
 563                                req_len, vma->vm_page_prot);
 564 }
 565
 566 int vfio_platform_mmap(struct vfio_device *core_vdev, struct vm_area_struct *vma)
 567 {
 568         struct vfio_platform_device *vdev =
 569                 container_of(core_vdev, struct vfio_platform_device, vdev);
 570         unsigned int index;
 571
 572         index = vma->vm_pgoff >> (VFIO_PLATFORM_OFFSET_SHIFT - PAGE_SHIFT);
 573
 574         if (vma->vm_end < vma->vm_start)
 575                 return -EINVAL;
 576         if (!(vma->vm_flags & VM_SHARED))
 577                 return -EINVAL;
 578         if (index >= vdev->num_regions)
 579                 return -EINVAL;
 580         if (vma->vm_start & ~PAGE_MASK)
 581                 return -EINVAL;
 582         if (vma->vm_end & ~PAGE_MASK)
 583                 return -EINVAL;
 584
 585         if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_MMAP))
 586                 return -EINVAL;
 587
 588         if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_READ)
 589                         && (vma->vm_flags & VM_READ))
 590                 return -EINVAL;
 591
 592         if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_WRITE)
 593                         && (vma->vm_flags & VM_WRITE))
 594                 return -EINVAL;
 595
 596         vma->vm_private_data = vdev;
 597
 598         if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_MMIO)
 599                 return vfio_platform_mmap_mmio(vdev->regions[index], vma);
 600
 601         else if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_PIO)
 602                 return -EINVAL; /* not implemented */
 603
 604         return -EINVAL;
 605 }
 606 EXPORT_SYMBOL_GPL(vfio_platform_mmap);
 607
 608 static int vfio_platform_of_probe(struct vfio_platform_device *vdev,
 609                            struct device *dev)
 610 {
 611         int ret;
 612
 613         ret = device_property_read_string(dev, "compatible",
 614                                           &vdev->compat);
 615         if (ret)
 616                 dev_err(dev, "Cannot retrieve compat for %s\n", vdev->name);
 617
 618         return ret;
 619 }
 620
 621 /*
 622  * There can be two kernel build combinations. One build where
 623  * ACPI is not selected in Kconfig and another one with the ACPI Kconfig.
 624  *
 625  * In the first case, vfio_platform_acpi_probe will return since
 626  * acpi_disabled is 1. DT user will not see any kind of messages from
 627  * ACPI.
 628  *
 629  * In the second case, both DT and ACPI is compiled in but the system is
 630  * booting with any of these combinations.
 631  *
 632  * If the firmware is DT type, then acpi_disabled is 1. The ACPI probe routine
 633  * terminates immediately without any messages.
 634  *
 635  * If the firmware is ACPI type, then acpi_disabled is 0. All other checks are
 636  * valid checks. We cannot claim that this system is DT.
 637  */
 638 int vfio_platform_init_common(struct vfio_platform_device *vdev)
 639 {
 640         int ret;
 641         struct device *dev = vdev->vdev.dev;
 642
 643         ret = vfio_platform_acpi_probe(vdev, dev);
 644         if (ret)
 645                 ret = vfio_platform_of_probe(vdev, dev);
 646
 647         if (ret)
 648                 return ret;
 649
 650         vdev->device = dev;
 651         mutex_init(&vdev->igate);
 652
 653         ret = vfio_platform_get_reset(vdev);
 654         if (ret && vdev->reset_required)
 655                 dev_err(dev, "No reset function found for device %s\n",
 656                         vdev->name);
 657         return ret;
 658 }
 659 EXPORT_SYMBOL_GPL(vfio_platform_init_common);
 660
 661 void vfio_platform_release_common(struct vfio_platform_device *vdev)
 662 {
 663         vfio_platform_put_reset(vdev);
 664 }
 665 EXPORT_SYMBOL_GPL(vfio_platform_release_common);
 666
 667 void __vfio_platform_register_reset(struct vfio_platform_reset_node *node)
 668 {
 669         mutex_lock(&driver_lock);
 670         list_add(&node->link, &reset_list);
 671         mutex_unlock(&driver_lock);
 672 }
 673 EXPORT_SYMBOL_GPL(__vfio_platform_register_reset);
 674
 675 void vfio_platform_unregister_reset(const char *compat,
 676                                     vfio_platform_reset_fn_t fn)
 677 {
 678         struct vfio_platform_reset_node *iter, *temp;
 679
 680         mutex_lock(&driver_lock);
 681         list_for_each_entry_safe(iter, temp, &reset_list, link) {
 682                 if (!strcmp(iter->compat, compat) && (iter->of_reset == fn)) {
 683                         list_del(&iter->link);
 684                         break;
 685                 }
 686         }
 687
 688         mutex_unlock(&driver_lock);
 689
 690 }
 691 EXPORT_SYMBOL_GPL(vfio_platform_unregister_reset);
 692
 693 MODULE_VERSION(DRIVER_VERSION);
 694 MODULE_LICENSE("GPL v2");
 695 MODULE_AUTHOR(DRIVER_AUTHOR);
 696 MODULE_DESCRIPTION(DRIVER_DESC);