drivers/vfio/pci/vfio_pci_intrs.c

   1 /*
   2  * VFIO PCI interrupt handling
   3  *
   4  * Copyright (C) 2012 Red Hat, Inc.  All rights reserved.
   5  *     Author: Alex Williamson <alex.williamson@redhat.com>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2 as
   9  * published by the Free Software Foundation.
  10  *
  11  * Derived from original vfio:
  12  * Copyright 2010 Cisco Systems, Inc.  All rights reserved.
  13  * Author: Tom Lyon, pugs@cisco.com
  14  */
  15
  16 #include <linux/device.h>
  17 #include <linux/interrupt.h>
  18 #include <linux/eventfd.h>
  19 #include <linux/msi.h>
  20 #include <linux/pci.h>
  21 #include <linux/file.h>
  22 #include <linux/vfio.h>
  23 #include <linux/wait.h>
  24 #include <linux/slab.h>
  25
  26 #include "vfio_pci_private.h"
  27
  28 /*
  29  * INTx
  30  */
  31 static void vfio_send_intx_eventfd(void *opaque, void *unused)
  32 {
  33         struct vfio_pci_device *vdev = opaque;
  34
  35         if (likely(is_intx(vdev) && !vdev->virq_disabled))
  36                 eventfd_signal(vdev->ctx[0].trigger, 1);
  37 }
  38
  39 void vfio_pci_intx_mask(struct vfio_pci_device *vdev)
  40 {
  41         struct pci_dev *pdev = vdev->pdev;
  42         unsigned long flags;
  43
  44         spin_lock_irqsave(&vdev->irqlock, flags);
  45
  46         /*
  47          * Masking can come from interrupt, ioctl, or config space
  48          * via INTx disable.  The latter means this can get called
  49          * even when not using intx delivery.  In this case, just
  50          * try to have the physical bit follow the virtual bit.
  51          */
  52         if (unlikely(!is_intx(vdev))) {
  53                 if (vdev->pci_2_3)
  54                         pci_intx(pdev, 0);
  55         } else if (!vdev->ctx[0].masked) {
  56                 /*
  57                  * Can't use check_and_mask here because we always want to
  58                  * mask, not just when something is pending.
  59                  */
  60                 if (vdev->pci_2_3)
  61                         pci_intx(pdev, 0);
  62                 else
  63                         disable_irq_nosync(pdev->irq);
  64
  65                 vdev->ctx[0].masked = true;
  66         }
  67
  68         spin_unlock_irqrestore(&vdev->irqlock, flags);
  69 }
  70
  71 /*
  72  * If this is triggered by an eventfd, we can't call eventfd_signal
  73  * or else we'll deadlock on the eventfd wait queue.  Return >0 when
  74  * a signal is necessary, which can then be handled via a work queue
  75  * or directly depending on the caller.
  76  */
  77 static int vfio_pci_intx_unmask_handler(void *opaque, void *unused)
  78 {
  79         struct vfio_pci_device *vdev = opaque;
  80         struct pci_dev *pdev = vdev->pdev;
  81         unsigned long flags;
  82         int ret = 0;
  83
  84         spin_lock_irqsave(&vdev->irqlock, flags);
  85
  86         /*
  87          * Unmasking comes from ioctl or config, so again, have the
  88          * physical bit follow the virtual even when not using INTx.
  89          */
  90         if (unlikely(!is_intx(vdev))) {
  91                 if (vdev->pci_2_3)
  92                         pci_intx(pdev, 1);
  93         } else if (vdev->ctx[0].masked && !vdev->virq_disabled) {
  94                 /*
  95                  * A pending interrupt here would immediately trigger,
  96                  * but we can avoid that overhead by just re-sending
  97                  * the interrupt to the user.
  98                  */
  99                 if (vdev->pci_2_3) {
 100                         if (!pci_check_and_unmask_intx(pdev))
 101                                 ret = 1;
 102                 } else
 103                         enable_irq(pdev->irq);
 104
 105                 vdev->ctx[0].masked = (ret > 0);
 106         }
 107
 108         spin_unlock_irqrestore(&vdev->irqlock, flags);
 109
 110         return ret;
 111 }
 112
 113 void vfio_pci_intx_unmask(struct vfio_pci_device *vdev)
 114 {
 115         if (vfio_pci_intx_unmask_handler(vdev, NULL) > 0)
 116                 vfio_send_intx_eventfd(vdev, NULL);
 117 }
 118
 119 static irqreturn_t vfio_intx_handler(int irq, void *dev_id)
 120 {
 121         struct vfio_pci_device *vdev = dev_id;
 122         unsigned long flags;
 123         int ret = IRQ_NONE;
 124
 125         spin_lock_irqsave(&vdev->irqlock, flags);
 126
 127         if (!vdev->pci_2_3) {
 128                 disable_irq_nosync(vdev->pdev->irq);
 129                 vdev->ctx[0].masked = true;
 130                 ret = IRQ_HANDLED;
 131         } else if (!vdev->ctx[0].masked &&  /* may be shared */
 132                    pci_check_and_mask_intx(vdev->pdev)) {
 133                 vdev->ctx[0].masked = true;
 134                 ret = IRQ_HANDLED;
 135         }
 136
 137         spin_unlock_irqrestore(&vdev->irqlock, flags);
 138
 139         if (ret == IRQ_HANDLED)
 140                 vfio_send_intx_eventfd(vdev, NULL);
 141
 142         return ret;
 143 }
 144
 145 static int vfio_intx_enable(struct vfio_pci_device *vdev)
 146 {
 147         if (!is_irq_none(vdev))
 148                 return -EINVAL;
 149
 150         if (!vdev->pdev->irq)
 151                 return -ENODEV;
 152
 153         vdev->ctx = kzalloc(sizeof(struct vfio_pci_irq_ctx), GFP_KERNEL);
 154         if (!vdev->ctx)
 155                 return -ENOMEM;
 156
 157         vdev->num_ctx = 1;
 158
 159         /*
 160          * If the virtual interrupt is masked, restore it.  Devices
 161          * supporting DisINTx can be masked at the hardware level
 162          * here, non-PCI-2.3 devices will have to wait until the
 163          * interrupt is enabled.
 164          */
 165         vdev->ctx[0].masked = vdev->virq_disabled;
 166         if (vdev->pci_2_3)
 167                 pci_intx(vdev->pdev, !vdev->ctx[0].masked);
 168
 169         vdev->irq_type = VFIO_PCI_INTX_IRQ_INDEX;
 170
 171         return 0;
 172 }
 173
 174 static int vfio_intx_set_signal(struct vfio_pci_device *vdev, int fd)
 175 {
 176         struct pci_dev *pdev = vdev->pdev;
 177         unsigned long irqflags = IRQF_SHARED;
 178         struct eventfd_ctx *trigger;
 179         unsigned long flags;
 180         int ret;
 181
 182         if (vdev->ctx[0].trigger) {
 183                 free_irq(pdev->irq, vdev);
 184                 kfree(vdev->ctx[0].name);
 185                 eventfd_ctx_put(vdev->ctx[0].trigger);
 186                 vdev->ctx[0].trigger = NULL;
 187         }
 188
 189         if (fd < 0) /* Disable only */
 190                 return 0;
 191
 192         vdev->ctx[0].name = kasprintf(GFP_KERNEL, "vfio-intx(%s)",
 193                                       pci_name(pdev));
 194         if (!vdev->ctx[0].name)
 195                 return -ENOMEM;
 196
 197         trigger = eventfd_ctx_fdget(fd);
 198         if (IS_ERR(trigger)) {
 199                 kfree(vdev->ctx[0].name);
 200                 return PTR_ERR(trigger);
 201         }
 202
 203         vdev->ctx[0].trigger = trigger;
 204
 205         if (!vdev->pci_2_3)
 206                 irqflags = 0;
 207
 208         ret = request_irq(pdev->irq, vfio_intx_handler,
 209                           irqflags, vdev->ctx[0].name, vdev);
 210         if (ret) {
 211                 vdev->ctx[0].trigger = NULL;
 212                 kfree(vdev->ctx[0].name);
 213                 eventfd_ctx_put(trigger);
 214                 return ret;
 215         }
 216
 217         /*
 218          * INTx disable will stick across the new irq setup,
 219          * disable_irq won't.
 220          */
 221         spin_lock_irqsave(&vdev->irqlock, flags);
 222         if (!vdev->pci_2_3 && vdev->ctx[0].masked)
 223                 disable_irq_nosync(pdev->irq);
 224         spin_unlock_irqrestore(&vdev->irqlock, flags);
 225
 226         return 0;
 227 }
 228
 229 static void vfio_intx_disable(struct vfio_pci_device *vdev)
 230 {
 231         vfio_virqfd_disable(&vdev->ctx[0].unmask);
 232         vfio_virqfd_disable(&vdev->ctx[0].mask);
 233         vfio_intx_set_signal(vdev, -1);
 234         vdev->irq_type = VFIO_PCI_NUM_IRQS;
 235         vdev->num_ctx = 0;
 236         kfree(vdev->ctx);
 237 }
 238
 239 /*
 240  * MSI/MSI-X
 241  */
 242 static irqreturn_t vfio_msihandler(int irq, void *arg)
 243 {
 244         struct eventfd_ctx *trigger = arg;
 245
 246         eventfd_signal(trigger, 1);
 247         return IRQ_HANDLED;
 248 }
 249
 250 static int vfio_msi_enable(struct vfio_pci_device *vdev, int nvec, bool msix)
 251 {
 252         struct pci_dev *pdev = vdev->pdev;
 253         int ret;
 254
 255         if (!is_irq_none(vdev))
 256                 return -EINVAL;
 257
 258         vdev->ctx = kzalloc(nvec * sizeof(struct vfio_pci_irq_ctx), GFP_KERNEL);
 259         if (!vdev->ctx)
 260                 return -ENOMEM;
 261
 262         if (msix) {
 263                 int i;
 264
 265                 vdev->msix = kzalloc(nvec * sizeof(struct msix_entry),
 266                                      GFP_KERNEL);
 267                 if (!vdev->msix) {
 268                         kfree(vdev->ctx);
 269                         return -ENOMEM;
 270                 }
 271
 272                 for (i = 0; i < nvec; i++)
 273                         vdev->msix[i].entry = i;
 274
 275                 ret = pci_enable_msix_range(pdev, vdev->msix, 1, nvec);
 276                 if (ret < nvec) {
 277                         if (ret > 0)
 278                                 pci_disable_msix(pdev);
 279                         kfree(vdev->msix);
 280                         kfree(vdev->ctx);
 281                         return ret;
 282                 }
 283         } else {
 284                 ret = pci_enable_msi_range(pdev, 1, nvec);
 285                 if (ret < nvec) {
 286                         if (ret > 0)
 287                                 pci_disable_msi(pdev);
 288                         kfree(vdev->ctx);
 289                         return ret;
 290                 }
 291         }
 292
 293         vdev->num_ctx = nvec;
 294         vdev->irq_type = msix ? VFIO_PCI_MSIX_IRQ_INDEX :
 295                                 VFIO_PCI_MSI_IRQ_INDEX;
 296
 297         if (!msix) {
 298                 /*
 299                  * Compute the virtual hardware field for max msi vectors -
 300                  * it is the log base 2 of the number of vectors.
 301                  */
 302                 vdev->msi_qmax = fls(nvec * 2 - 1) - 1;
 303         }
 304
 305         return 0;
 306 }
 307
 308 static int vfio_msi_set_vector_signal(struct vfio_pci_device *vdev,
 309                                       int vector, int fd, bool msix)
 310 {
 311         struct pci_dev *pdev = vdev->pdev;
 312         struct eventfd_ctx *trigger;
 313         int irq, ret;
 314
 315         if (vector < 0 || vector >= vdev->num_ctx)
 316                 return -EINVAL;
 317
 318         irq = msix ? vdev->msix[vector].vector : pdev->irq + vector;
 319
 320         if (vdev->ctx[vector].trigger) {
 321                 free_irq(irq, vdev->ctx[vector].trigger);
 322                 irq_bypass_unregister_producer(&vdev->ctx[vector].producer);
 323                 kfree(vdev->ctx[vector].name);
 324                 eventfd_ctx_put(vdev->ctx[vector].trigger);
 325                 vdev->ctx[vector].trigger = NULL;
 326         }
 327
 328         if (fd < 0)
 329                 return 0;
 330
 331         vdev->ctx[vector].name = kasprintf(GFP_KERNEL, "vfio-msi%s[%d](%s)",
 332                                            msix ? "x" : "", vector,
 333                                            pci_name(pdev));
 334         if (!vdev->ctx[vector].name)
 335                 return -ENOMEM;
 336
 337         trigger = eventfd_ctx_fdget(fd);
 338         if (IS_ERR(trigger)) {
 339                 kfree(vdev->ctx[vector].name);
 340                 return PTR_ERR(trigger);
 341         }
 342
 343         /*
 344          * The MSIx vector table resides in device memory which may be cleared
 345          * via backdoor resets. We don't allow direct access to the vector
 346          * table so even if a userspace driver attempts to save/restore around
 347          * such a reset it would be unsuccessful. To avoid this, restore the
 348          * cached value of the message prior to enabling.
 349          */
 350         if (msix) {
 351                 struct msi_msg msg;
 352
 353                 get_cached_msi_msg(irq, &msg);
 354                 pci_write_msi_msg(irq, &msg);
 355         }
 356
 357         ret = request_irq(irq, vfio_msihandler, 0,
 358                           vdev->ctx[vector].name, trigger);
 359         if (ret) {
 360                 kfree(vdev->ctx[vector].name);
 361                 eventfd_ctx_put(trigger);
 362                 return ret;
 363         }
 364
 365         vdev->ctx[vector].producer.token = trigger;
 366         vdev->ctx[vector].producer.irq = irq;
 367         ret = irq_bypass_register_producer(&vdev->ctx[vector].producer);
 368         if (unlikely(ret))
 369                 dev_info(&pdev->dev,
 370                 "irq bypass producer (token %p) registration fails: %d\n",
 371                 vdev->ctx[vector].producer.token, ret);
 372
 373         vdev->ctx[vector].trigger = trigger;
 374
 375         return 0;
 376 }
 377
 378 static int vfio_msi_set_block(struct vfio_pci_device *vdev, unsigned start,
 379                               unsigned count, int32_t *fds, bool msix)
 380 {
 381         int i, j, ret = 0;
 382
 383         if (start >= vdev->num_ctx || start + count > vdev->num_ctx)
 384                 return -EINVAL;
 385
 386         for (i = 0, j = start; i < count && !ret; i++, j++) {
 387                 int fd = fds ? fds[i] : -1;
 388                 ret = vfio_msi_set_vector_signal(vdev, j, fd, msix);
 389         }
 390
 391         if (ret) {
 392                 for (--j; j >= (int)start; j--)
 393                         vfio_msi_set_vector_signal(vdev, j, -1, msix);
 394         }
 395
 396         return ret;
 397 }
 398
 399 static void vfio_msi_disable(struct vfio_pci_device *vdev, bool msix)
 400 {
 401         struct pci_dev *pdev = vdev->pdev;
 402         int i;
 403
 404         for (i = 0; i < vdev->num_ctx; i++) {
 405                 vfio_virqfd_disable(&vdev->ctx[i].unmask);
 406                 vfio_virqfd_disable(&vdev->ctx[i].mask);
 407         }
 408
 409         vfio_msi_set_block(vdev, 0, vdev->num_ctx, NULL, msix);
 410
 411         if (msix) {
 412                 pci_disable_msix(vdev->pdev);
 413                 kfree(vdev->msix);
 414         } else
 415                 pci_disable_msi(pdev);
 416
 417         vdev->irq_type = VFIO_PCI_NUM_IRQS;
 418         vdev->num_ctx = 0;
 419         kfree(vdev->ctx);
 420 }
 421
 422 /*
 423  * IOCTL support
 424  */
 425 static int vfio_pci_set_intx_unmask(struct vfio_pci_device *vdev,
 426                                     unsigned index, unsigned start,
 427                                     unsigned count, uint32_t flags, void *data)
 428 {
 429         if (!is_intx(vdev) || start != 0 || count != 1)
 430                 return -EINVAL;
 431
 432         if (flags & VFIO_IRQ_SET_DATA_NONE) {
 433                 vfio_pci_intx_unmask(vdev);
 434         } else if (flags & VFIO_IRQ_SET_DATA_BOOL) {
 435                 uint8_t unmask = *(uint8_t *)data;
 436                 if (unmask)
 437                         vfio_pci_intx_unmask(vdev);
 438         } else if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
 439                 int32_t fd = *(int32_t *)data;
 440                 if (fd >= 0)
 441                         return vfio_virqfd_enable((void *) vdev,
 442                                                   vfio_pci_intx_unmask_handler,
 443                                                   vfio_send_intx_eventfd, NULL,
 444                                                   &vdev->ctx[0].unmask, fd);
 445
 446                 vfio_virqfd_disable(&vdev->ctx[0].unmask);
 447         }
 448
 449         return 0;
 450 }
 451
 452 static int vfio_pci_set_intx_mask(struct vfio_pci_device *vdev,
 453                                   unsigned index, unsigned start,
 454                                   unsigned count, uint32_t flags, void *data)
 455 {
 456         if (!is_intx(vdev) || start != 0 || count != 1)
 457                 return -EINVAL;
 458
 459         if (flags & VFIO_IRQ_SET_DATA_NONE) {
 460                 vfio_pci_intx_mask(vdev);
 461         } else if (flags & VFIO_IRQ_SET_DATA_BOOL) {
 462                 uint8_t mask = *(uint8_t *)data;
 463                 if (mask)
 464                         vfio_pci_intx_mask(vdev);
 465         } else if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
 466                 return -ENOTTY; /* XXX implement me */
 467         }
 468
 469         return 0;
 470 }
 471
 472 static int vfio_pci_set_intx_trigger(struct vfio_pci_device *vdev,
 473                                      unsigned index, unsigned start,
 474                                      unsigned count, uint32_t flags, void *data)
 475 {
 476         if (is_intx(vdev) && !count && (flags & VFIO_IRQ_SET_DATA_NONE)) {
 477                 vfio_intx_disable(vdev);
 478                 return 0;
 479         }
 480
 481         if (!(is_intx(vdev) || is_irq_none(vdev)) || start != 0 || count != 1)
 482                 return -EINVAL;
 483
 484         if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
 485                 int32_t fd = *(int32_t *)data;
 486                 int ret;
 487
 488                 if (is_intx(vdev))
 489                         return vfio_intx_set_signal(vdev, fd);
 490
 491                 ret = vfio_intx_enable(vdev);
 492                 if (ret)
 493                         return ret;
 494
 495                 ret = vfio_intx_set_signal(vdev, fd);
 496                 if (ret)
 497                         vfio_intx_disable(vdev);
 498
 499                 return ret;
 500         }
 501
 502         if (!is_intx(vdev))
 503                 return -EINVAL;
 504
 505         if (flags & VFIO_IRQ_SET_DATA_NONE) {
 506                 vfio_send_intx_eventfd(vdev, NULL);
 507         } else if (flags & VFIO_IRQ_SET_DATA_BOOL) {
 508                 uint8_t trigger = *(uint8_t *)data;
 509                 if (trigger)
 510                         vfio_send_intx_eventfd(vdev, NULL);
 511         }
 512         return 0;
 513 }
 514
 515 static int vfio_pci_set_msi_trigger(struct vfio_pci_device *vdev,
 516                                     unsigned index, unsigned start,
 517                                     unsigned count, uint32_t flags, void *data)
 518 {
 519         int i;
 520         bool msix = (index == VFIO_PCI_MSIX_IRQ_INDEX) ? true : false;
 521
 522         if (irq_is(vdev, index) && !count && (flags & VFIO_IRQ_SET_DATA_NONE)) {
 523                 vfio_msi_disable(vdev, msix);
 524                 return 0;
 525         }
 526
 527         if (!(irq_is(vdev, index) || is_irq_none(vdev)))
 528                 return -EINVAL;
 529
 530         if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
 531                 int32_t *fds = data;
 532                 int ret;
 533
 534                 if (vdev->irq_type == index)
 535                         return vfio_msi_set_block(vdev, start, count,
 536                                                   fds, msix);
 537
 538                 ret = vfio_msi_enable(vdev, start + count, msix);
 539                 if (ret)
 540                         return ret;
 541
 542                 ret = vfio_msi_set_block(vdev, start, count, fds, msix);
 543                 if (ret)
 544                         vfio_msi_disable(vdev, msix);
 545
 546                 return ret;
 547         }
 548
 549         if (!irq_is(vdev, index) || start + count > vdev->num_ctx)
 550                 return -EINVAL;
 551
 552         for (i = start; i < start + count; i++) {
 553                 if (!vdev->ctx[i].trigger)
 554                         continue;
 555                 if (flags & VFIO_IRQ_SET_DATA_NONE) {
 556                         eventfd_signal(vdev->ctx[i].trigger, 1);
 557                 } else if (flags & VFIO_IRQ_SET_DATA_BOOL) {
 558                         uint8_t *bools = data;
 559                         if (bools[i - start])
 560                                 eventfd_signal(vdev->ctx[i].trigger, 1);
 561                 }
 562         }
 563         return 0;
 564 }
 565
 566 static int vfio_pci_set_ctx_trigger_single(struct eventfd_ctx **ctx,
 567                                            unsigned int count, uint32_t flags,
 568                                            void *data)
 569 {
 570         /* DATA_NONE/DATA_BOOL enables loopback testing */
 571         if (flags & VFIO_IRQ_SET_DATA_NONE) {
 572                 if (*ctx) {
 573                         if (count) {
 574                                 eventfd_signal(*ctx, 1);
 575                         } else {
 576                                 eventfd_ctx_put(*ctx);
 577                                 *ctx = NULL;
 578                         }
 579                         return 0;
 580                 }
 581         } else if (flags & VFIO_IRQ_SET_DATA_BOOL) {
 582                 uint8_t trigger;
 583
 584                 if (!count)
 585                         return -EINVAL;
 586
 587                 trigger = *(uint8_t *)data;
 588                 if (trigger && *ctx)
 589                         eventfd_signal(*ctx, 1);
 590
 591                 return 0;
 592         } else if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
 593                 int32_t fd;
 594
 595                 if (!count)
 596                         return -EINVAL;
 597
 598                 fd = *(int32_t *)data;
 599                 if (fd == -1) {
 600                         if (*ctx)
 601                                 eventfd_ctx_put(*ctx);
 602                         *ctx = NULL;
 603                 } else if (fd >= 0) {
 604                         struct eventfd_ctx *efdctx;
 605
 606                         efdctx = eventfd_ctx_fdget(fd);
 607                         if (IS_ERR(efdctx))
 608                                 return PTR_ERR(efdctx);
 609
 610                         if (*ctx)
 611                                 eventfd_ctx_put(*ctx);
 612
 613                         *ctx = efdctx;
 614                 }
 615                 return 0;
 616         }
 617
 618         return -EINVAL;
 619 }
 620
 621 static int vfio_pci_set_err_trigger(struct vfio_pci_device *vdev,
 622                                     unsigned index, unsigned start,
 623                                     unsigned count, uint32_t flags, void *data)
 624 {
 625         if (index != VFIO_PCI_ERR_IRQ_INDEX || start != 0 || count > 1)
 626                 return -EINVAL;
 627
 628         return vfio_pci_set_ctx_trigger_single(&vdev->err_trigger,
 629                                                count, flags, data);
 630 }
 631
 632 static int vfio_pci_set_req_trigger(struct vfio_pci_device *vdev,
 633                                     unsigned index, unsigned start,
 634                                     unsigned count, uint32_t flags, void *data)
 635 {
 636         if (index != VFIO_PCI_REQ_IRQ_INDEX || start != 0 || count > 1)
 637                 return -EINVAL;
 638
 639         return vfio_pci_set_ctx_trigger_single(&vdev->req_trigger,
 640                                                count, flags, data);
 641 }
 642
 643 int vfio_pci_set_irqs_ioctl(struct vfio_pci_device *vdev, uint32_t flags,
 644                             unsigned index, unsigned start, unsigned count,
 645                             void *data)
 646 {
 647         int (*func)(struct vfio_pci_device *vdev, unsigned index,
 648                     unsigned start, unsigned count, uint32_t flags,
 649                     void *data) = NULL;
 650
 651         switch (index) {
 652         case VFIO_PCI_INTX_IRQ_INDEX:
 653                 switch (flags & VFIO_IRQ_SET_ACTION_TYPE_MASK) {
 654                 case VFIO_IRQ_SET_ACTION_MASK:
 655                         func = vfio_pci_set_intx_mask;
 656                         break;
 657                 case VFIO_IRQ_SET_ACTION_UNMASK:
 658                         func = vfio_pci_set_intx_unmask;
 659                         break;
 660                 case VFIO_IRQ_SET_ACTION_TRIGGER:
 661                         func = vfio_pci_set_intx_trigger;
 662                         break;
 663                 }
 664                 break;
 665         case VFIO_PCI_MSI_IRQ_INDEX:
 666         case VFIO_PCI_MSIX_IRQ_INDEX:
 667                 switch (flags & VFIO_IRQ_SET_ACTION_TYPE_MASK) {
 668                 case VFIO_IRQ_SET_ACTION_MASK:
 669                 case VFIO_IRQ_SET_ACTION_UNMASK:
 670                         /* XXX Need masking support exported */
 671                         break;
 672                 case VFIO_IRQ_SET_ACTION_TRIGGER:
 673                         func = vfio_pci_set_msi_trigger;
 674                         break;
 675                 }
 676                 break;
 677         case VFIO_PCI_ERR_IRQ_INDEX:
 678                 switch (flags & VFIO_IRQ_SET_ACTION_TYPE_MASK) {
 679                 case VFIO_IRQ_SET_ACTION_TRIGGER:
 680                         if (pci_is_pcie(vdev->pdev))
 681                                 func = vfio_pci_set_err_trigger;
 682                         break;
 683                 }
 684                 break;
 685         case VFIO_PCI_REQ_IRQ_INDEX:
 686                 switch (flags & VFIO_IRQ_SET_ACTION_TYPE_MASK) {
 687                 case VFIO_IRQ_SET_ACTION_TRIGGER:
 688                         func = vfio_pci_set_req_trigger;
 689                         break;
 690                 }
 691                 break;
 692         }
 693
 694         if (!func)
 695                 return -ENOTTY;
 696
 697         return func(vdev, index, start, count, flags, data);
 698 }