linux/drivers/vfio/pci/vfio_pci_intrs.c
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   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 */
  31static 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
  39void 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 */
  77static 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
 113void 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
 119static 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
 145static 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
 174static 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
 229static 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 */
 242static 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
 250static int vfio_msi_enable(struct vfio_pci_device *vdev, int nvec, bool msix)
 251{
 252        struct pci_dev *pdev = vdev->pdev;
 253        unsigned int flag = msix ? PCI_IRQ_MSIX : PCI_IRQ_MSI;
 254        int ret;
 255
 256        if (!is_irq_none(vdev))
 257                return -EINVAL;
 258
 259        vdev->ctx = kcalloc(nvec, sizeof(struct vfio_pci_irq_ctx), GFP_KERNEL);
 260        if (!vdev->ctx)
 261                return -ENOMEM;
 262
 263        /* return the number of supported vectors if we can't get all: */
 264        ret = pci_alloc_irq_vectors(pdev, 1, nvec, flag);
 265        if (ret < nvec) {
 266                if (ret > 0)
 267                        pci_free_irq_vectors(pdev);
 268                kfree(vdev->ctx);
 269                return ret;
 270        }
 271
 272        vdev->num_ctx = nvec;
 273        vdev->irq_type = msix ? VFIO_PCI_MSIX_IRQ_INDEX :
 274                                VFIO_PCI_MSI_IRQ_INDEX;
 275
 276        if (!msix) {
 277                /*
 278                 * Compute the virtual hardware field for max msi vectors -
 279                 * it is the log base 2 of the number of vectors.
 280                 */
 281                vdev->msi_qmax = fls(nvec * 2 - 1) - 1;
 282        }
 283
 284        return 0;
 285}
 286
 287static int vfio_msi_set_vector_signal(struct vfio_pci_device *vdev,
 288                                      int vector, int fd, bool msix)
 289{
 290        struct pci_dev *pdev = vdev->pdev;
 291        struct eventfd_ctx *trigger;
 292        int irq, ret;
 293
 294        if (vector < 0 || vector >= vdev->num_ctx)
 295                return -EINVAL;
 296
 297        irq = pci_irq_vector(pdev, vector);
 298
 299        if (vdev->ctx[vector].trigger) {
 300                free_irq(irq, vdev->ctx[vector].trigger);
 301                irq_bypass_unregister_producer(&vdev->ctx[vector].producer);
 302                kfree(vdev->ctx[vector].name);
 303                eventfd_ctx_put(vdev->ctx[vector].trigger);
 304                vdev->ctx[vector].trigger = NULL;
 305        }
 306
 307        if (fd < 0)
 308                return 0;
 309
 310        vdev->ctx[vector].name = kasprintf(GFP_KERNEL, "vfio-msi%s[%d](%s)",
 311                                           msix ? "x" : "", vector,
 312                                           pci_name(pdev));
 313        if (!vdev->ctx[vector].name)
 314                return -ENOMEM;
 315
 316        trigger = eventfd_ctx_fdget(fd);
 317        if (IS_ERR(trigger)) {
 318                kfree(vdev->ctx[vector].name);
 319                return PTR_ERR(trigger);
 320        }
 321
 322        /*
 323         * The MSIx vector table resides in device memory which may be cleared
 324         * via backdoor resets. We don't allow direct access to the vector
 325         * table so even if a userspace driver attempts to save/restore around
 326         * such a reset it would be unsuccessful. To avoid this, restore the
 327         * cached value of the message prior to enabling.
 328         */
 329        if (msix) {
 330                struct msi_msg msg;
 331
 332                get_cached_msi_msg(irq, &msg);
 333                pci_write_msi_msg(irq, &msg);
 334        }
 335
 336        ret = request_irq(irq, vfio_msihandler, 0,
 337                          vdev->ctx[vector].name, trigger);
 338        if (ret) {
 339                kfree(vdev->ctx[vector].name);
 340                eventfd_ctx_put(trigger);
 341                return ret;
 342        }
 343
 344        vdev->ctx[vector].producer.token = trigger;
 345        vdev->ctx[vector].producer.irq = irq;
 346        ret = irq_bypass_register_producer(&vdev->ctx[vector].producer);
 347        if (unlikely(ret))
 348                dev_info(&pdev->dev,
 349                "irq bypass producer (token %p) registration fails: %d\n",
 350                vdev->ctx[vector].producer.token, ret);
 351
 352        vdev->ctx[vector].trigger = trigger;
 353
 354        return 0;
 355}
 356
 357static int vfio_msi_set_block(struct vfio_pci_device *vdev, unsigned start,
 358                              unsigned count, int32_t *fds, bool msix)
 359{
 360        int i, j, ret = 0;
 361
 362        if (start >= vdev->num_ctx || start + count > vdev->num_ctx)
 363                return -EINVAL;
 364
 365        for (i = 0, j = start; i < count && !ret; i++, j++) {
 366                int fd = fds ? fds[i] : -1;
 367                ret = vfio_msi_set_vector_signal(vdev, j, fd, msix);
 368        }
 369
 370        if (ret) {
 371                for (--j; j >= (int)start; j--)
 372                        vfio_msi_set_vector_signal(vdev, j, -1, msix);
 373        }
 374
 375        return ret;
 376}
 377
 378static void vfio_msi_disable(struct vfio_pci_device *vdev, bool msix)
 379{
 380        struct pci_dev *pdev = vdev->pdev;
 381        int i;
 382
 383        for (i = 0; i < vdev->num_ctx; i++) {
 384                vfio_virqfd_disable(&vdev->ctx[i].unmask);
 385                vfio_virqfd_disable(&vdev->ctx[i].mask);
 386        }
 387
 388        vfio_msi_set_block(vdev, 0, vdev->num_ctx, NULL, msix);
 389
 390        pci_free_irq_vectors(pdev);
 391
 392        /*
 393         * Both disable paths above use pci_intx_for_msi() to clear DisINTx
 394         * via their shutdown paths.  Restore for NoINTx devices.
 395         */
 396        if (vdev->nointx)
 397                pci_intx(pdev, 0);
 398
 399        vdev->irq_type = VFIO_PCI_NUM_IRQS;
 400        vdev->num_ctx = 0;
 401        kfree(vdev->ctx);
 402}
 403
 404/*
 405 * IOCTL support
 406 */
 407static int vfio_pci_set_intx_unmask(struct vfio_pci_device *vdev,
 408                                    unsigned index, unsigned start,
 409                                    unsigned count, uint32_t flags, void *data)
 410{
 411        if (!is_intx(vdev) || start != 0 || count != 1)
 412                return -EINVAL;
 413
 414        if (flags & VFIO_IRQ_SET_DATA_NONE) {
 415                vfio_pci_intx_unmask(vdev);
 416        } else if (flags & VFIO_IRQ_SET_DATA_BOOL) {
 417                uint8_t unmask = *(uint8_t *)data;
 418                if (unmask)
 419                        vfio_pci_intx_unmask(vdev);
 420        } else if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
 421                int32_t fd = *(int32_t *)data;
 422                if (fd >= 0)
 423                        return vfio_virqfd_enable((void *) vdev,
 424                                                  vfio_pci_intx_unmask_handler,
 425                                                  vfio_send_intx_eventfd, NULL,
 426                                                  &vdev->ctx[0].unmask, fd);
 427
 428                vfio_virqfd_disable(&vdev->ctx[0].unmask);
 429        }
 430
 431        return 0;
 432}
 433
 434static int vfio_pci_set_intx_mask(struct vfio_pci_device *vdev,
 435                                  unsigned index, unsigned start,
 436                                  unsigned count, uint32_t flags, void *data)
 437{
 438        if (!is_intx(vdev) || start != 0 || count != 1)
 439                return -EINVAL;
 440
 441        if (flags & VFIO_IRQ_SET_DATA_NONE) {
 442                vfio_pci_intx_mask(vdev);
 443        } else if (flags & VFIO_IRQ_SET_DATA_BOOL) {
 444                uint8_t mask = *(uint8_t *)data;
 445                if (mask)
 446                        vfio_pci_intx_mask(vdev);
 447        } else if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
 448                return -ENOTTY; /* XXX implement me */
 449        }
 450
 451        return 0;
 452}
 453
 454static int vfio_pci_set_intx_trigger(struct vfio_pci_device *vdev,
 455                                     unsigned index, unsigned start,
 456                                     unsigned count, uint32_t flags, void *data)
 457{
 458        if (is_intx(vdev) && !count && (flags & VFIO_IRQ_SET_DATA_NONE)) {
 459                vfio_intx_disable(vdev);
 460                return 0;
 461        }
 462
 463        if (!(is_intx(vdev) || is_irq_none(vdev)) || start != 0 || count != 1)
 464                return -EINVAL;
 465
 466        if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
 467                int32_t fd = *(int32_t *)data;
 468                int ret;
 469
 470                if (is_intx(vdev))
 471                        return vfio_intx_set_signal(vdev, fd);
 472
 473                ret = vfio_intx_enable(vdev);
 474                if (ret)
 475                        return ret;
 476
 477                ret = vfio_intx_set_signal(vdev, fd);
 478                if (ret)
 479                        vfio_intx_disable(vdev);
 480
 481                return ret;
 482        }
 483
 484        if (!is_intx(vdev))
 485                return -EINVAL;
 486
 487        if (flags & VFIO_IRQ_SET_DATA_NONE) {
 488                vfio_send_intx_eventfd(vdev, NULL);
 489        } else if (flags & VFIO_IRQ_SET_DATA_BOOL) {
 490                uint8_t trigger = *(uint8_t *)data;
 491                if (trigger)
 492                        vfio_send_intx_eventfd(vdev, NULL);
 493        }
 494        return 0;
 495}
 496
 497static int vfio_pci_set_msi_trigger(struct vfio_pci_device *vdev,
 498                                    unsigned index, unsigned start,
 499                                    unsigned count, uint32_t flags, void *data)
 500{
 501        int i;
 502        bool msix = (index == VFIO_PCI_MSIX_IRQ_INDEX) ? true : false;
 503
 504        if (irq_is(vdev, index) && !count && (flags & VFIO_IRQ_SET_DATA_NONE)) {
 505                vfio_msi_disable(vdev, msix);
 506                return 0;
 507        }
 508
 509        if (!(irq_is(vdev, index) || is_irq_none(vdev)))
 510                return -EINVAL;
 511
 512        if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
 513                int32_t *fds = data;
 514                int ret;
 515
 516                if (vdev->irq_type == index)
 517                        return vfio_msi_set_block(vdev, start, count,
 518                                                  fds, msix);
 519
 520                ret = vfio_msi_enable(vdev, start + count, msix);
 521                if (ret)
 522                        return ret;
 523
 524                ret = vfio_msi_set_block(vdev, start, count, fds, msix);
 525                if (ret)
 526                        vfio_msi_disable(vdev, msix);
 527
 528                return ret;
 529        }
 530
 531        if (!irq_is(vdev, index) || start + count > vdev->num_ctx)
 532                return -EINVAL;
 533
 534        for (i = start; i < start + count; i++) {
 535                if (!vdev->ctx[i].trigger)
 536                        continue;
 537                if (flags & VFIO_IRQ_SET_DATA_NONE) {
 538                        eventfd_signal(vdev->ctx[i].trigger, 1);
 539                } else if (flags & VFIO_IRQ_SET_DATA_BOOL) {
 540                        uint8_t *bools = data;
 541                        if (bools[i - start])
 542                                eventfd_signal(vdev->ctx[i].trigger, 1);
 543                }
 544        }
 545        return 0;
 546}
 547
 548static int vfio_pci_set_ctx_trigger_single(struct eventfd_ctx **ctx,
 549                                           unsigned int count, uint32_t flags,
 550                                           void *data)
 551{
 552        /* DATA_NONE/DATA_BOOL enables loopback testing */
 553        if (flags & VFIO_IRQ_SET_DATA_NONE) {
 554                if (*ctx) {
 555                        if (count) {
 556                                eventfd_signal(*ctx, 1);
 557                        } else {
 558                                eventfd_ctx_put(*ctx);
 559                                *ctx = NULL;
 560                        }
 561                        return 0;
 562                }
 563        } else if (flags & VFIO_IRQ_SET_DATA_BOOL) {
 564                uint8_t trigger;
 565
 566                if (!count)
 567                        return -EINVAL;
 568
 569                trigger = *(uint8_t *)data;
 570                if (trigger && *ctx)
 571                        eventfd_signal(*ctx, 1);
 572
 573                return 0;
 574        } else if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
 575                int32_t fd;
 576
 577                if (!count)
 578                        return -EINVAL;
 579
 580                fd = *(int32_t *)data;
 581                if (fd == -1) {
 582                        if (*ctx)
 583                                eventfd_ctx_put(*ctx);
 584                        *ctx = NULL;
 585                } else if (fd >= 0) {
 586                        struct eventfd_ctx *efdctx;
 587
 588                        efdctx = eventfd_ctx_fdget(fd);
 589                        if (IS_ERR(efdctx))
 590                                return PTR_ERR(efdctx);
 591
 592                        if (*ctx)
 593                                eventfd_ctx_put(*ctx);
 594
 595                        *ctx = efdctx;
 596                }
 597                return 0;
 598        }
 599
 600        return -EINVAL;
 601}
 602
 603static int vfio_pci_set_err_trigger(struct vfio_pci_device *vdev,
 604                                    unsigned index, unsigned start,
 605                                    unsigned count, uint32_t flags, void *data)
 606{
 607        if (index != VFIO_PCI_ERR_IRQ_INDEX || start != 0 || count > 1)
 608                return -EINVAL;
 609
 610        return vfio_pci_set_ctx_trigger_single(&vdev->err_trigger,
 611                                               count, flags, data);
 612}
 613
 614static int vfio_pci_set_req_trigger(struct vfio_pci_device *vdev,
 615                                    unsigned index, unsigned start,
 616                                    unsigned count, uint32_t flags, void *data)
 617{
 618        if (index != VFIO_PCI_REQ_IRQ_INDEX || start != 0 || count > 1)
 619                return -EINVAL;
 620
 621        return vfio_pci_set_ctx_trigger_single(&vdev->req_trigger,
 622                                               count, flags, data);
 623}
 624
 625int vfio_pci_set_irqs_ioctl(struct vfio_pci_device *vdev, uint32_t flags,
 626                            unsigned index, unsigned start, unsigned count,
 627                            void *data)
 628{
 629        int (*func)(struct vfio_pci_device *vdev, unsigned index,
 630                    unsigned start, unsigned count, uint32_t flags,
 631                    void *data) = NULL;
 632
 633        switch (index) {
 634        case VFIO_PCI_INTX_IRQ_INDEX:
 635                switch (flags & VFIO_IRQ_SET_ACTION_TYPE_MASK) {
 636                case VFIO_IRQ_SET_ACTION_MASK:
 637                        func = vfio_pci_set_intx_mask;
 638                        break;
 639                case VFIO_IRQ_SET_ACTION_UNMASK:
 640                        func = vfio_pci_set_intx_unmask;
 641                        break;
 642                case VFIO_IRQ_SET_ACTION_TRIGGER:
 643                        func = vfio_pci_set_intx_trigger;
 644                        break;
 645                }
 646                break;
 647        case VFIO_PCI_MSI_IRQ_INDEX:
 648        case VFIO_PCI_MSIX_IRQ_INDEX:
 649                switch (flags & VFIO_IRQ_SET_ACTION_TYPE_MASK) {
 650                case VFIO_IRQ_SET_ACTION_MASK:
 651                case VFIO_IRQ_SET_ACTION_UNMASK:
 652                        /* XXX Need masking support exported */
 653                        break;
 654                case VFIO_IRQ_SET_ACTION_TRIGGER:
 655                        func = vfio_pci_set_msi_trigger;
 656                        break;
 657                }
 658                break;
 659        case VFIO_PCI_ERR_IRQ_INDEX:
 660                switch (flags & VFIO_IRQ_SET_ACTION_TYPE_MASK) {
 661                case VFIO_IRQ_SET_ACTION_TRIGGER:
 662                        if (pci_is_pcie(vdev->pdev))
 663                                func = vfio_pci_set_err_trigger;
 664                        break;
 665                }
 666                break;
 667        case VFIO_PCI_REQ_IRQ_INDEX:
 668                switch (flags & VFIO_IRQ_SET_ACTION_TYPE_MASK) {
 669                case VFIO_IRQ_SET_ACTION_TRIGGER:
 670                        func = vfio_pci_set_req_trigger;
 671                        break;
 672                }
 673                break;
 674        }
 675
 676        if (!func)
 677                return -ENOTTY;
 678
 679        return func(vdev, index, start, count, flags, data);
 680}
 681