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         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
 287 static 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                 irq_bypass_unregister_producer(&vdev->ctx[vector].producer);
 301                 free_irq(irq, vdev->ctx[vector].trigger);
 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
 357 static 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
 378 static 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  */
 407 static 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
 434 static 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
 454 static 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
 497 static 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
 548 static 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
 603 static 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
 614 static 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
 625 int 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 }