LXR linux/drivers/vfio/pci/vfio_pci

   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * VFIO PCI interrupt handling
   4 *
   5 * Copyright (C) 2012 Red Hat, Inc.  All rights reserved.
   6 *     Author: Alex Williamson <alex.williamson@redhat.com>
   7 *
   8 * Derived from original vfio:
   9 * Copyright 2010 Cisco Systems, Inc.  All rights reserved.
  10 * Author: Tom Lyon, pugs@cisco.com
  11 */
  12
  13#include <linux/device.h>
  14#include <linux/interrupt.h>
  15#include <linux/eventfd.h>
  16#include <linux/msi.h>
  17#include <linux/pci.h>
  18#include <linux/file.h>
  19#include <linux/vfio.h>
  20#include <linux/wait.h>
  21#include <linux/slab.h>
  22
  23#include <linux/vfio_pci_core.h>
  24
  25/*
  26 * INTx
  27 */
  28static void vfio_send_intx_eventfd(void *opaque, void *unused)
  29{
  30        struct vfio_pci_core_device *vdev = opaque;
  31
  32        if (likely(is_intx(vdev) && !vdev->virq_disabled))
  33                eventfd_signal(vdev->ctx[0].trigger, 1);
  34}
  35
  36void vfio_pci_intx_mask(struct vfio_pci_core_device *vdev)
  37{
  38        struct pci_dev *pdev = vdev->pdev;
  39        unsigned long flags;
  40
  41        spin_lock_irqsave(&vdev->irqlock, flags);
  42
  43        /*
  44         * Masking can come from interrupt, ioctl, or config space
  45         * via INTx disable.  The latter means this can get called
  46         * even when not using intx delivery.  In this case, just
  47         * try to have the physical bit follow the virtual bit.
  48         */
  49        if (unlikely(!is_intx(vdev))) {
  50                if (vdev->pci_2_3)
  51                        pci_intx(pdev, 0);
  52        } else if (!vdev->ctx[0].masked) {
  53                /*
  54                 * Can't use check_and_mask here because we always want to
  55                 * mask, not just when something is pending.
  56                 */
  57                if (vdev->pci_2_3)
  58                        pci_intx(pdev, 0);
  59                else
  60                        disable_irq_nosync(pdev->irq);
  61
  62                vdev->ctx[0].masked = true;
  63        }
  64
  65        spin_unlock_irqrestore(&vdev->irqlock, flags);
  66}
  67
  68/*
  69 * If this is triggered by an eventfd, we can't call eventfd_signal
  70 * or else we'll deadlock on the eventfd wait queue.  Return >0 when
  71 * a signal is necessary, which can then be handled via a work queue
  72 * or directly depending on the caller.
  73 */
  74static int vfio_pci_intx_unmask_handler(void *opaque, void *unused)
  75{
  76        struct vfio_pci_core_device *vdev = opaque;
  77        struct pci_dev *pdev = vdev->pdev;
  78        unsigned long flags;
  79        int ret = 0;
  80
  81        spin_lock_irqsave(&vdev->irqlock, flags);
  82
  83        /*
  84         * Unmasking comes from ioctl or config, so again, have the
  85         * physical bit follow the virtual even when not using INTx.
  86         */
  87        if (unlikely(!is_intx(vdev))) {
  88                if (vdev->pci_2_3)
  89                        pci_intx(pdev, 1);
  90        } else if (vdev->ctx[0].masked && !vdev->virq_disabled) {
  91                /*
  92                 * A pending interrupt here would immediately trigger,
  93                 * but we can avoid that overhead by just re-sending
  94                 * the interrupt to the user.
  95                 */
  96                if (vdev->pci_2_3) {
  97                        if (!pci_check_and_unmask_intx(pdev))
  98                                ret = 1;
  99                } else
 100                        enable_irq(pdev->irq);
 101
 102                vdev->ctx[0].masked = (ret > 0);
 103        }
 104
 105        spin_unlock_irqrestore(&vdev->irqlock, flags);
 106
 107        return ret;
 108}
 109
 110void vfio_pci_intx_unmask(struct vfio_pci_core_device *vdev)
 111{
 112        if (vfio_pci_intx_unmask_handler(vdev, NULL) > 0)
 113                vfio_send_intx_eventfd(vdev, NULL);
 114}
 115
 116static irqreturn_t vfio_intx_handler(int irq, void *dev_id)
 117{
 118        struct vfio_pci_core_device *vdev = dev_id;
 119        unsigned long flags;
 120        int ret = IRQ_NONE;
 121
 122        spin_lock_irqsave(&vdev->irqlock, flags);
 123
 124        if (!vdev->pci_2_3) {
 125                disable_irq_nosync(vdev->pdev->irq);
 126                vdev->ctx[0].masked = true;
 127                ret = IRQ_HANDLED;
 128        } else if (!vdev->ctx[0].masked &&  /* may be shared */
 129                   pci_check_and_mask_intx(vdev->pdev)) {
 130                vdev->ctx[0].masked = true;
 131                ret = IRQ_HANDLED;
 132        }
 133
 134        spin_unlock_irqrestore(&vdev->irqlock, flags);
 135
 136        if (ret == IRQ_HANDLED)
 137                vfio_send_intx_eventfd(vdev, NULL);
 138
 139        return ret;
 140}
 141
 142static int vfio_intx_enable(struct vfio_pci_core_device *vdev)
 143{
 144        if (!is_irq_none(vdev))
 145                return -EINVAL;
 146
 147        if (!vdev->pdev->irq)
 148                return -ENODEV;
 149
 150        vdev->ctx = kzalloc(sizeof(struct vfio_pci_irq_ctx), GFP_KERNEL);
 151        if (!vdev->ctx)
 152                return -ENOMEM;
 153
 154        vdev->num_ctx = 1;
 155
 156        /*
 157         * If the virtual interrupt is masked, restore it.  Devices
 158         * supporting DisINTx can be masked at the hardware level
 159         * here, non-PCI-2.3 devices will have to wait until the
 160         * interrupt is enabled.
 161         */
 162        vdev->ctx[0].masked = vdev->virq_disabled;
 163        if (vdev->pci_2_3)
 164                pci_intx(vdev->pdev, !vdev->ctx[0].masked);
 165
 166        vdev->irq_type = VFIO_PCI_INTX_IRQ_INDEX;
 167
 168        return 0;
 169}
 170
 171static int vfio_intx_set_signal(struct vfio_pci_core_device *vdev, int fd)
 172{
 173        struct pci_dev *pdev = vdev->pdev;
 174        unsigned long irqflags = IRQF_SHARED;
 175        struct eventfd_ctx *trigger;
 176        unsigned long flags;
 177        int ret;
 178
 179        if (vdev->ctx[0].trigger) {
 180                free_irq(pdev->irq, vdev);
 181                kfree(vdev->ctx[0].name);
 182                eventfd_ctx_put(vdev->ctx[0].trigger);
 183                vdev->ctx[0].trigger = NULL;
 184        }
 185
 186        if (fd < 0) /* Disable only */
 187                return 0;
 188
 189        vdev->ctx[0].name = kasprintf(GFP_KERNEL, "vfio-intx(%s)",
 190                                      pci_name(pdev));
 191        if (!vdev->ctx[0].name)
 192                return -ENOMEM;
 193
 194        trigger = eventfd_ctx_fdget(fd);
 195        if (IS_ERR(trigger)) {
 196                kfree(vdev->ctx[0].name);
 197                return PTR_ERR(trigger);
 198        }
 199
 200        vdev->ctx[0].trigger = trigger;
 201
 202        if (!vdev->pci_2_3)
 203                irqflags = 0;
 204
 205        ret = request_irq(pdev->irq, vfio_intx_handler,
 206                          irqflags, vdev->ctx[0].name, vdev);
 207        if (ret) {
 208                vdev->ctx[0].trigger = NULL;
 209                kfree(vdev->ctx[0].name);
 210                eventfd_ctx_put(trigger);
 211                return ret;
 212        }
 213
 214        /*
 215         * INTx disable will stick across the new irq setup,
 216         * disable_irq won't.
 217         */
 218        spin_lock_irqsave(&vdev->irqlock, flags);
 219        if (!vdev->pci_2_3 && vdev->ctx[0].masked)
 220                disable_irq_nosync(pdev->irq);
 221        spin_unlock_irqrestore(&vdev->irqlock, flags);
 222
 223        return 0;
 224}
 225
 226static void vfio_intx_disable(struct vfio_pci_core_device *vdev)
 227{
 228        vfio_virqfd_disable(&vdev->ctx[0].unmask);
 229        vfio_virqfd_disable(&vdev->ctx[0].mask);
 230        vfio_intx_set_signal(vdev, -1);
 231        vdev->irq_type = VFIO_PCI_NUM_IRQS;
 232        vdev->num_ctx = 0;
 233        kfree(vdev->ctx);
 234}
 235
 236/*
 237 * MSI/MSI-X
 238 */
 239static irqreturn_t vfio_msihandler(int irq, void *arg)
 240{
 241        struct eventfd_ctx *trigger = arg;
 242
 243        eventfd_signal(trigger, 1);
 244        return IRQ_HANDLED;
 245}
 246
 247static int vfio_msi_enable(struct vfio_pci_core_device *vdev, int nvec, bool msix)
 248{
 249        struct pci_dev *pdev = vdev->pdev;
 250        unsigned int flag = msix ? PCI_IRQ_MSIX : PCI_IRQ_MSI;
 251        int ret;
 252        u16 cmd;
 253
 254        if (!is_irq_none(vdev))
 255                return -EINVAL;
 256
 257        vdev->ctx = kcalloc(nvec, sizeof(struct vfio_pci_irq_ctx), GFP_KERNEL);
 258        if (!vdev->ctx)
 259                return -ENOMEM;
 260
 261        /* return the number of supported vectors if we can't get all: */
 262        cmd = vfio_pci_memory_lock_and_enable(vdev);
 263        ret = pci_alloc_irq_vectors(pdev, 1, nvec, flag);
 264        if (ret < nvec) {
 265                if (ret > 0)
 266                        pci_free_irq_vectors(pdev);
 267                vfio_pci_memory_unlock_and_restore(vdev, cmd);
 268                kfree(vdev->ctx);
 269                return ret;
 270        }
 271        vfio_pci_memory_unlock_and_restore(vdev, cmd);
 272
 273        vdev->num_ctx = nvec;
 274        vdev->irq_type = msix ? VFIO_PCI_MSIX_IRQ_INDEX :
 275                                VFIO_PCI_MSI_IRQ_INDEX;
 276
 277        if (!msix) {
 278                /*
 279                 * Compute the virtual hardware field for max msi vectors -
 280                 * it is the log base 2 of the number of vectors.
 281                 */
 282                vdev->msi_qmax = fls(nvec * 2 - 1) - 1;
 283        }
 284
 285        return 0;
 286}
 287
 288static int vfio_msi_set_vector_signal(struct vfio_pci_core_device *vdev,
 289                                      int vector, int fd, bool msix)
 290{
 291        struct pci_dev *pdev = vdev->pdev;
 292        struct eventfd_ctx *trigger;
 293        int irq, ret;
 294        u16 cmd;
 295
 296        if (vector < 0 || vector >= vdev->num_ctx)
 297                return -EINVAL;
 298
 299        irq = pci_irq_vector(pdev, vector);
 300
 301        if (vdev->ctx[vector].trigger) {
 302                irq_bypass_unregister_producer(&vdev->ctx[vector].producer);
 303
 304                cmd = vfio_pci_memory_lock_and_enable(vdev);
 305                free_irq(irq, vdev->ctx[vector].trigger);
 306                vfio_pci_memory_unlock_and_restore(vdev, cmd);
 307
 308                kfree(vdev->ctx[vector].name);
 309                eventfd_ctx_put(vdev->ctx[vector].trigger);
 310                vdev->ctx[vector].trigger = NULL;
 311        }
 312
 313        if (fd < 0)
 314                return 0;
 315
 316        vdev->ctx[vector].name = kasprintf(GFP_KERNEL, "vfio-msi%s[%d](%s)",
 317                                           msix ? "x" : "", vector,
 318                                           pci_name(pdev));
 319        if (!vdev->ctx[vector].name)
 320                return -ENOMEM;
 321
 322        trigger = eventfd_ctx_fdget(fd);
 323        if (IS_ERR(trigger)) {
 324                kfree(vdev->ctx[vector].name);
 325                return PTR_ERR(trigger);
 326        }
 327
 328        /*
 329         * The MSIx vector table resides in device memory which may be cleared
 330         * via backdoor resets. We don't allow direct access to the vector
 331         * table so even if a userspace driver attempts to save/restore around
 332         * such a reset it would be unsuccessful. To avoid this, restore the
 333         * cached value of the message prior to enabling.
 334         */
 335        cmd = vfio_pci_memory_lock_and_enable(vdev);
 336        if (msix) {
 337                struct msi_msg msg;
 338
 339                get_cached_msi_msg(irq, &msg);
 340                pci_write_msi_msg(irq, &msg);
 341        }
 342
 343        ret = request_irq(irq, vfio_msihandler, 0,
 344                          vdev->ctx[vector].name, trigger);
 345        vfio_pci_memory_unlock_and_restore(vdev, cmd);
 346        if (ret) {
 347                kfree(vdev->ctx[vector].name);
 348                eventfd_ctx_put(trigger);
 349                return ret;
 350        }
 351
 352        vdev->ctx[vector].producer.token = trigger;
 353        vdev->ctx[vector].producer.irq = irq;
 354        ret = irq_bypass_register_producer(&vdev->ctx[vector].producer);
 355        if (unlikely(ret)) {
 356                dev_info(&pdev->dev,
 357                "irq bypass producer (token %p) registration fails: %d\n",
 358                vdev->ctx[vector].producer.token, ret);
 359
 360                vdev->ctx[vector].producer.token = NULL;
 361        }
 362        vdev->ctx[vector].trigger = trigger;
 363
 364        return 0;
 365}
 366
 367static int vfio_msi_set_block(struct vfio_pci_core_device *vdev, unsigned start,
 368                              unsigned count, int32_t *fds, bool msix)
 369{
 370        int i, j, ret = 0;
 371
 372        if (start >= vdev->num_ctx || start + count > vdev->num_ctx)
 373                return -EINVAL;
 374
 375        for (i = 0, j = start; i < count && !ret; i++, j++) {
 376                int fd = fds ? fds[i] : -1;
 377                ret = vfio_msi_set_vector_signal(vdev, j, fd, msix);
 378        }
 379
 380        if (ret) {
 381                for (--j; j >= (int)start; j--)
 382                        vfio_msi_set_vector_signal(vdev, j, -1, msix);
 383        }
 384
 385        return ret;
 386}
 387
 388static void vfio_msi_disable(struct vfio_pci_core_device *vdev, bool msix)
 389{
 390        struct pci_dev *pdev = vdev->pdev;
 391        int i;
 392        u16 cmd;
 393
 394        for (i = 0; i < vdev->num_ctx; i++) {
 395                vfio_virqfd_disable(&vdev->ctx[i].unmask);
 396                vfio_virqfd_disable(&vdev->ctx[i].mask);
 397        }
 398
 399        vfio_msi_set_block(vdev, 0, vdev->num_ctx, NULL, msix);
 400
 401        cmd = vfio_pci_memory_lock_and_enable(vdev);
 402        pci_free_irq_vectors(pdev);
 403        vfio_pci_memory_unlock_and_restore(vdev, cmd);
 404
 405        /*
 406         * Both disable paths above use pci_intx_for_msi() to clear DisINTx
 407         * via their shutdown paths.  Restore for NoINTx devices.
 408         */
 409        if (vdev->nointx)
 410                pci_intx(pdev, 0);
 411
 412        vdev->irq_type = VFIO_PCI_NUM_IRQS;
 413        vdev->num_ctx = 0;
 414        kfree(vdev->ctx);
 415}
 416
 417/*
 418 * IOCTL support
 419 */
 420static int vfio_pci_set_intx_unmask(struct vfio_pci_core_device *vdev,
 421                                    unsigned index, unsigned start,
 422                                    unsigned count, uint32_t flags, void *data)
 423{
 424        if (!is_intx(vdev) || start != 0 || count != 1)
 425                return -EINVAL;
 426
 427        if (flags & VFIO_IRQ_SET_DATA_NONE) {
 428                vfio_pci_intx_unmask(vdev);
 429        } else if (flags & VFIO_IRQ_SET_DATA_BOOL) {
 430                uint8_t unmask = *(uint8_t *)data;
 431                if (unmask)
 432                        vfio_pci_intx_unmask(vdev);
 433        } else if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
 434                int32_t fd = *(int32_t *)data;
 435                if (fd >= 0)
 436                        return vfio_virqfd_enable((void *) vdev,
 437                                                  vfio_pci_intx_unmask_handler,
 438                                                  vfio_send_intx_eventfd, NULL,
 439                                                  &vdev->ctx[0].unmask, fd);
 440
 441                vfio_virqfd_disable(&vdev->ctx[0].unmask);
 442        }
 443
 444        return 0;
 445}
 446
 447static int vfio_pci_set_intx_mask(struct vfio_pci_core_device *vdev,
 448                                  unsigned index, unsigned start,
 449                                  unsigned count, uint32_t flags, void *data)
 450{
 451        if (!is_intx(vdev) || start != 0 || count != 1)
 452                return -EINVAL;
 453
 454        if (flags & VFIO_IRQ_SET_DATA_NONE) {
 455                vfio_pci_intx_mask(vdev);
 456        } else if (flags & VFIO_IRQ_SET_DATA_BOOL) {
 457                uint8_t mask = *(uint8_t *)data;
 458                if (mask)
 459                        vfio_pci_intx_mask(vdev);
 460        } else if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
 461                return -ENOTTY; /* XXX implement me */
 462        }
 463
 464        return 0;
 465}
 466
 467static int vfio_pci_set_intx_trigger(struct vfio_pci_core_device *vdev,
 468                                     unsigned index, unsigned start,
 469                                     unsigned count, uint32_t flags, void *data)
 470{
 471        if (is_intx(vdev) && !count && (flags & VFIO_IRQ_SET_DATA_NONE)) {
 472                vfio_intx_disable(vdev);
 473                return 0;
 474        }
 475
 476        if (!(is_intx(vdev) || is_irq_none(vdev)) || start != 0 || count != 1)
 477                return -EINVAL;
 478
 479        if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
 480                int32_t fd = *(int32_t *)data;
 481                int ret;
 482
 483                if (is_intx(vdev))
 484                        return vfio_intx_set_signal(vdev, fd);
 485
 486                ret = vfio_intx_enable(vdev);
 487                if (ret)
 488                        return ret;
 489
 490                ret = vfio_intx_set_signal(vdev, fd);
 491                if (ret)
 492                        vfio_intx_disable(vdev);
 493
 494                return ret;
 495        }
 496
 497        if (!is_intx(vdev))
 498                return -EINVAL;
 499
 500        if (flags & VFIO_IRQ_SET_DATA_NONE) {
 501                vfio_send_intx_eventfd(vdev, NULL);
 502        } else if (flags & VFIO_IRQ_SET_DATA_BOOL) {
 503                uint8_t trigger = *(uint8_t *)data;
 504                if (trigger)
 505                        vfio_send_intx_eventfd(vdev, NULL);
 506        }
 507        return 0;
 508}
 509
 510static int vfio_pci_set_msi_trigger(struct vfio_pci_core_device *vdev,
 511                                    unsigned index, unsigned start,
 512                                    unsigned count, uint32_t flags, void *data)
 513{
 514        int i;
 515        bool msix = (index == VFIO_PCI_MSIX_IRQ_INDEX) ? true : false;
 516
 517        if (irq_is(vdev, index) && !count && (flags & VFIO_IRQ_SET_DATA_NONE)) {
 518                vfio_msi_disable(vdev, msix);
 519                return 0;
 520        }
 521
 522        if (!(irq_is(vdev, index) || is_irq_none(vdev)))
 523                return -EINVAL;
 524
 525        if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
 526                int32_t *fds = data;
 527                int ret;
 528
 529                if (vdev->irq_type == index)
 530                        return vfio_msi_set_block(vdev, start, count,
 531                                                  fds, msix);
 532
 533                ret = vfio_msi_enable(vdev, start + count, msix);
 534                if (ret)
 535                        return ret;
 536
 537                ret = vfio_msi_set_block(vdev, start, count, fds, msix);
 538                if (ret)
 539                        vfio_msi_disable(vdev, msix);
 540
 541                return ret;
 542        }
 543
 544        if (!irq_is(vdev, index) || start + count > vdev->num_ctx)
 545                return -EINVAL;
 546
 547        for (i = start; i < start + count; i++) {
 548                if (!vdev->ctx[i].trigger)
 549                        continue;
 550                if (flags & VFIO_IRQ_SET_DATA_NONE) {
 551                        eventfd_signal(vdev->ctx[i].trigger, 1);
 552                } else if (flags & VFIO_IRQ_SET_DATA_BOOL) {
 553                        uint8_t *bools = data;
 554                        if (bools[i - start])
 555                                eventfd_signal(vdev->ctx[i].trigger, 1);
 556                }
 557        }
 558        return 0;
 559}
 560
 561static int vfio_pci_set_ctx_trigger_single(struct eventfd_ctx **ctx,
 562                                           unsigned int count, uint32_t flags,
 563                                           void *data)
 564{
 565        /* DATA_NONE/DATA_BOOL enables loopback testing */
 566        if (flags & VFIO_IRQ_SET_DATA_NONE) {
 567                if (*ctx) {
 568                        if (count) {
 569                                eventfd_signal(*ctx, 1);
 570                        } else {
 571                                eventfd_ctx_put(*ctx);
 572                                *ctx = NULL;
 573                        }
 574                        return 0;
 575                }
 576        } else if (flags & VFIO_IRQ_SET_DATA_BOOL) {
 577                uint8_t trigger;
 578
 579                if (!count)
 580                        return -EINVAL;
 581
 582                trigger = *(uint8_t *)data;
 583                if (trigger && *ctx)
 584                        eventfd_signal(*ctx, 1);
 585
 586                return 0;
 587        } else if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
 588                int32_t fd;
 589
 590                if (!count)
 591                        return -EINVAL;
 592
 593                fd = *(int32_t *)data;
 594                if (fd == -1) {
 595                        if (*ctx)
 596                                eventfd_ctx_put(*ctx);
 597                        *ctx = NULL;
 598                } else if (fd >= 0) {
 599                        struct eventfd_ctx *efdctx;
 600
 601                        efdctx = eventfd_ctx_fdget(fd);
 602                        if (IS_ERR(efdctx))
 603                                return PTR_ERR(efdctx);
 604
 605                        if (*ctx)
 606                                eventfd_ctx_put(*ctx);
 607
 608                        *ctx = efdctx;
 609                }
 610                return 0;
 611        }
 612
 613        return -EINVAL;
 614}
 615
 616static int vfio_pci_set_err_trigger(struct vfio_pci_core_device *vdev,
 617                                    unsigned index, unsigned start,
 618                                    unsigned count, uint32_t flags, void *data)
 619{
 620        if (index != VFIO_PCI_ERR_IRQ_INDEX || start != 0 || count > 1)
 621                return -EINVAL;
 622
 623        return vfio_pci_set_ctx_trigger_single(&vdev->err_trigger,
 624                                               count, flags, data);
 625}
 626
 627static int vfio_pci_set_req_trigger(struct vfio_pci_core_device *vdev,
 628                                    unsigned index, unsigned start,
 629                                    unsigned count, uint32_t flags, void *data)
 630{
 631        if (index != VFIO_PCI_REQ_IRQ_INDEX || start != 0 || count > 1)
 632                return -EINVAL;
 633
 634        return vfio_pci_set_ctx_trigger_single(&vdev->req_trigger,
 635                                               count, flags, data);
 636}
 637
 638int vfio_pci_set_irqs_ioctl(struct vfio_pci_core_device *vdev, uint32_t flags,
 639                            unsigned index, unsigned start, unsigned count,
 640                            void *data)
 641{
 642        int (*func)(struct vfio_pci_core_device *vdev, unsigned index,
 643                    unsigned start, unsigned count, uint32_t flags,
 644                    void *data) = NULL;
 645
 646        switch (index) {
 647        case VFIO_PCI_INTX_IRQ_INDEX:
 648                switch (flags & VFIO_IRQ_SET_ACTION_TYPE_MASK) {
 649                case VFIO_IRQ_SET_ACTION_MASK:
 650                        func = vfio_pci_set_intx_mask;
 651                        break;
 652                case VFIO_IRQ_SET_ACTION_UNMASK:
 653                        func = vfio_pci_set_intx_unmask;
 654                        break;
 655                case VFIO_IRQ_SET_ACTION_TRIGGER:
 656                        func = vfio_pci_set_intx_trigger;
 657                        break;
 658                }
 659                break;
 660        case VFIO_PCI_MSI_IRQ_INDEX:
 661        case VFIO_PCI_MSIX_IRQ_INDEX:
 662                switch (flags & VFIO_IRQ_SET_ACTION_TYPE_MASK) {
 663                case VFIO_IRQ_SET_ACTION_MASK:
 664                case VFIO_IRQ_SET_ACTION_UNMASK:
 665                        /* XXX Need masking support exported */
 666                        break;
 667                case VFIO_IRQ_SET_ACTION_TRIGGER:
 668                        func = vfio_pci_set_msi_trigger;
 669                        break;
 670                }
 671                break;
 672        case VFIO_PCI_ERR_IRQ_INDEX:
 673                switch (flags & VFIO_IRQ_SET_ACTION_TYPE_MASK) {
 674                case VFIO_IRQ_SET_ACTION_TRIGGER:
 675                        if (pci_is_pcie(vdev->pdev))
 676                                func = vfio_pci_set_err_trigger;
 677                        break;
 678                }
 679                break;
 680        case VFIO_PCI_REQ_IRQ_INDEX:
 681                switch (flags & VFIO_IRQ_SET_ACTION_TYPE_MASK) {
 682                case VFIO_IRQ_SET_ACTION_TRIGGER:
 683                        func = vfio_pci_set_req_trigger;
 684                        break;
 685                }
 686                break;
 687        }
 688
 689        if (!func)
 690                return -ENOTTY;
 691
 692        return func(vdev, index, start, count, flags, data);
 693}
 694