xref: /qemu/hw/vfio/pci.c (revision c52125ab)
1 /*
2  * vfio based device assignment support
3  *
4  * Copyright Red Hat, Inc. 2012
5  *
6  * Authors:
7  *  Alex Williamson <alex.williamson@redhat.com>
8  *
9  * This work is licensed under the terms of the GNU GPL, version 2.  See
10  * the COPYING file in the top-level directory.
11  *
12  * Based on qemu-kvm device-assignment:
13  *  Adapted for KVM by Qumranet.
14  *  Copyright (c) 2007, Neocleus, Alex Novik (alex@neocleus.com)
15  *  Copyright (c) 2007, Neocleus, Guy Zana (guy@neocleus.com)
16  *  Copyright (C) 2008, Qumranet, Amit Shah (amit.shah@qumranet.com)
17  *  Copyright (C) 2008, Red Hat, Amit Shah (amit.shah@redhat.com)
18  *  Copyright (C) 2008, IBM, Muli Ben-Yehuda (muli@il.ibm.com)
19  */
20 
21 #include "qemu/osdep.h"
22 #include <linux/vfio.h>
23 #include <sys/ioctl.h>
24 
25 #include "hw/pci/msi.h"
26 #include "hw/pci/msix.h"
27 #include "hw/pci/pci_bridge.h"
28 #include "qemu/error-report.h"
29 #include "qemu/range.h"
30 #include "sysemu/kvm.h"
31 #include "sysemu/sysemu.h"
32 #include "pci.h"
33 #include "trace.h"
34 
35 #define MSIX_CAP_LENGTH 12
36 
37 static void vfio_disable_interrupts(VFIOPCIDevice *vdev);
38 static void vfio_mmap_set_enabled(VFIOPCIDevice *vdev, bool enabled);
39 
40 /*
41  * Disabling BAR mmaping can be slow, but toggling it around INTx can
42  * also be a huge overhead.  We try to get the best of both worlds by
43  * waiting until an interrupt to disable mmaps (subsequent transitions
44  * to the same state are effectively no overhead).  If the interrupt has
45  * been serviced and the time gap is long enough, we re-enable mmaps for
46  * performance.  This works well for things like graphics cards, which
47  * may not use their interrupt at all and are penalized to an unusable
48  * level by read/write BAR traps.  Other devices, like NICs, have more
49  * regular interrupts and see much better latency by staying in non-mmap
50  * mode.  We therefore set the default mmap_timeout such that a ping
51  * is just enough to keep the mmap disabled.  Users can experiment with
52  * other options with the x-intx-mmap-timeout-ms parameter (a value of
53  * zero disables the timer).
54  */
55 static void vfio_intx_mmap_enable(void *opaque)
56 {
57     VFIOPCIDevice *vdev = opaque;
58 
59     if (vdev->intx.pending) {
60         timer_mod(vdev->intx.mmap_timer,
61                        qemu_clock_get_ms(QEMU_CLOCK_VIRTUAL) + vdev->intx.mmap_timeout);
62         return;
63     }
64 
65     vfio_mmap_set_enabled(vdev, true);
66 }
67 
68 static void vfio_intx_interrupt(void *opaque)
69 {
70     VFIOPCIDevice *vdev = opaque;
71 
72     if (!event_notifier_test_and_clear(&vdev->intx.interrupt)) {
73         return;
74     }
75 
76     trace_vfio_intx_interrupt(vdev->vbasedev.name, 'A' + vdev->intx.pin);
77 
78     vdev->intx.pending = true;
79     pci_irq_assert(&vdev->pdev);
80     vfio_mmap_set_enabled(vdev, false);
81     if (vdev->intx.mmap_timeout) {
82         timer_mod(vdev->intx.mmap_timer,
83                        qemu_clock_get_ms(QEMU_CLOCK_VIRTUAL) + vdev->intx.mmap_timeout);
84     }
85 }
86 
87 static void vfio_intx_eoi(VFIODevice *vbasedev)
88 {
89     VFIOPCIDevice *vdev = container_of(vbasedev, VFIOPCIDevice, vbasedev);
90 
91     if (!vdev->intx.pending) {
92         return;
93     }
94 
95     trace_vfio_intx_eoi(vbasedev->name);
96 
97     vdev->intx.pending = false;
98     pci_irq_deassert(&vdev->pdev);
99     vfio_unmask_single_irqindex(vbasedev, VFIO_PCI_INTX_IRQ_INDEX);
100 }
101 
102 static void vfio_intx_enable_kvm(VFIOPCIDevice *vdev)
103 {
104 #ifdef CONFIG_KVM
105     struct kvm_irqfd irqfd = {
106         .fd = event_notifier_get_fd(&vdev->intx.interrupt),
107         .gsi = vdev->intx.route.irq,
108         .flags = KVM_IRQFD_FLAG_RESAMPLE,
109     };
110     struct vfio_irq_set *irq_set;
111     int ret, argsz;
112     int32_t *pfd;
113 
114     if (vdev->no_kvm_intx || !kvm_irqfds_enabled() ||
115         vdev->intx.route.mode != PCI_INTX_ENABLED ||
116         !kvm_resamplefds_enabled()) {
117         return;
118     }
119 
120     /* Get to a known interrupt state */
121     qemu_set_fd_handler(irqfd.fd, NULL, NULL, vdev);
122     vfio_mask_single_irqindex(&vdev->vbasedev, VFIO_PCI_INTX_IRQ_INDEX);
123     vdev->intx.pending = false;
124     pci_irq_deassert(&vdev->pdev);
125 
126     /* Get an eventfd for resample/unmask */
127     if (event_notifier_init(&vdev->intx.unmask, 0)) {
128         error_report("vfio: Error: event_notifier_init failed eoi");
129         goto fail;
130     }
131 
132     /* KVM triggers it, VFIO listens for it */
133     irqfd.resamplefd = event_notifier_get_fd(&vdev->intx.unmask);
134 
135     if (kvm_vm_ioctl(kvm_state, KVM_IRQFD, &irqfd)) {
136         error_report("vfio: Error: Failed to setup resample irqfd: %m");
137         goto fail_irqfd;
138     }
139 
140     argsz = sizeof(*irq_set) + sizeof(*pfd);
141 
142     irq_set = g_malloc0(argsz);
143     irq_set->argsz = argsz;
144     irq_set->flags = VFIO_IRQ_SET_DATA_EVENTFD | VFIO_IRQ_SET_ACTION_UNMASK;
145     irq_set->index = VFIO_PCI_INTX_IRQ_INDEX;
146     irq_set->start = 0;
147     irq_set->count = 1;
148     pfd = (int32_t *)&irq_set->data;
149 
150     *pfd = irqfd.resamplefd;
151 
152     ret = ioctl(vdev->vbasedev.fd, VFIO_DEVICE_SET_IRQS, irq_set);
153     g_free(irq_set);
154     if (ret) {
155         error_report("vfio: Error: Failed to setup INTx unmask fd: %m");
156         goto fail_vfio;
157     }
158 
159     /* Let'em rip */
160     vfio_unmask_single_irqindex(&vdev->vbasedev, VFIO_PCI_INTX_IRQ_INDEX);
161 
162     vdev->intx.kvm_accel = true;
163 
164     trace_vfio_intx_enable_kvm(vdev->vbasedev.name);
165 
166     return;
167 
168 fail_vfio:
169     irqfd.flags = KVM_IRQFD_FLAG_DEASSIGN;
170     kvm_vm_ioctl(kvm_state, KVM_IRQFD, &irqfd);
171 fail_irqfd:
172     event_notifier_cleanup(&vdev->intx.unmask);
173 fail:
174     qemu_set_fd_handler(irqfd.fd, vfio_intx_interrupt, NULL, vdev);
175     vfio_unmask_single_irqindex(&vdev->vbasedev, VFIO_PCI_INTX_IRQ_INDEX);
176 #endif
177 }
178 
179 static void vfio_intx_disable_kvm(VFIOPCIDevice *vdev)
180 {
181 #ifdef CONFIG_KVM
182     struct kvm_irqfd irqfd = {
183         .fd = event_notifier_get_fd(&vdev->intx.interrupt),
184         .gsi = vdev->intx.route.irq,
185         .flags = KVM_IRQFD_FLAG_DEASSIGN,
186     };
187 
188     if (!vdev->intx.kvm_accel) {
189         return;
190     }
191 
192     /*
193      * Get to a known state, hardware masked, QEMU ready to accept new
194      * interrupts, QEMU IRQ de-asserted.
195      */
196     vfio_mask_single_irqindex(&vdev->vbasedev, VFIO_PCI_INTX_IRQ_INDEX);
197     vdev->intx.pending = false;
198     pci_irq_deassert(&vdev->pdev);
199 
200     /* Tell KVM to stop listening for an INTx irqfd */
201     if (kvm_vm_ioctl(kvm_state, KVM_IRQFD, &irqfd)) {
202         error_report("vfio: Error: Failed to disable INTx irqfd: %m");
203     }
204 
205     /* We only need to close the eventfd for VFIO to cleanup the kernel side */
206     event_notifier_cleanup(&vdev->intx.unmask);
207 
208     /* QEMU starts listening for interrupt events. */
209     qemu_set_fd_handler(irqfd.fd, vfio_intx_interrupt, NULL, vdev);
210 
211     vdev->intx.kvm_accel = false;
212 
213     /* If we've missed an event, let it re-fire through QEMU */
214     vfio_unmask_single_irqindex(&vdev->vbasedev, VFIO_PCI_INTX_IRQ_INDEX);
215 
216     trace_vfio_intx_disable_kvm(vdev->vbasedev.name);
217 #endif
218 }
219 
220 static void vfio_intx_update(PCIDevice *pdev)
221 {
222     VFIOPCIDevice *vdev = DO_UPCAST(VFIOPCIDevice, pdev, pdev);
223     PCIINTxRoute route;
224 
225     if (vdev->interrupt != VFIO_INT_INTx) {
226         return;
227     }
228 
229     route = pci_device_route_intx_to_irq(&vdev->pdev, vdev->intx.pin);
230 
231     if (!pci_intx_route_changed(&vdev->intx.route, &route)) {
232         return; /* Nothing changed */
233     }
234 
235     trace_vfio_intx_update(vdev->vbasedev.name,
236                            vdev->intx.route.irq, route.irq);
237 
238     vfio_intx_disable_kvm(vdev);
239 
240     vdev->intx.route = route;
241 
242     if (route.mode != PCI_INTX_ENABLED) {
243         return;
244     }
245 
246     vfio_intx_enable_kvm(vdev);
247 
248     /* Re-enable the interrupt in cased we missed an EOI */
249     vfio_intx_eoi(&vdev->vbasedev);
250 }
251 
252 static int vfio_intx_enable(VFIOPCIDevice *vdev)
253 {
254     uint8_t pin = vfio_pci_read_config(&vdev->pdev, PCI_INTERRUPT_PIN, 1);
255     int ret, argsz;
256     struct vfio_irq_set *irq_set;
257     int32_t *pfd;
258 
259     if (!pin) {
260         return 0;
261     }
262 
263     vfio_disable_interrupts(vdev);
264 
265     vdev->intx.pin = pin - 1; /* Pin A (1) -> irq[0] */
266     pci_config_set_interrupt_pin(vdev->pdev.config, pin);
267 
268 #ifdef CONFIG_KVM
269     /*
270      * Only conditional to avoid generating error messages on platforms
271      * where we won't actually use the result anyway.
272      */
273     if (kvm_irqfds_enabled() && kvm_resamplefds_enabled()) {
274         vdev->intx.route = pci_device_route_intx_to_irq(&vdev->pdev,
275                                                         vdev->intx.pin);
276     }
277 #endif
278 
279     ret = event_notifier_init(&vdev->intx.interrupt, 0);
280     if (ret) {
281         error_report("vfio: Error: event_notifier_init failed");
282         return ret;
283     }
284 
285     argsz = sizeof(*irq_set) + sizeof(*pfd);
286 
287     irq_set = g_malloc0(argsz);
288     irq_set->argsz = argsz;
289     irq_set->flags = VFIO_IRQ_SET_DATA_EVENTFD | VFIO_IRQ_SET_ACTION_TRIGGER;
290     irq_set->index = VFIO_PCI_INTX_IRQ_INDEX;
291     irq_set->start = 0;
292     irq_set->count = 1;
293     pfd = (int32_t *)&irq_set->data;
294 
295     *pfd = event_notifier_get_fd(&vdev->intx.interrupt);
296     qemu_set_fd_handler(*pfd, vfio_intx_interrupt, NULL, vdev);
297 
298     ret = ioctl(vdev->vbasedev.fd, VFIO_DEVICE_SET_IRQS, irq_set);
299     g_free(irq_set);
300     if (ret) {
301         error_report("vfio: Error: Failed to setup INTx fd: %m");
302         qemu_set_fd_handler(*pfd, NULL, NULL, vdev);
303         event_notifier_cleanup(&vdev->intx.interrupt);
304         return -errno;
305     }
306 
307     vfio_intx_enable_kvm(vdev);
308 
309     vdev->interrupt = VFIO_INT_INTx;
310 
311     trace_vfio_intx_enable(vdev->vbasedev.name);
312 
313     return 0;
314 }
315 
316 static void vfio_intx_disable(VFIOPCIDevice *vdev)
317 {
318     int fd;
319 
320     timer_del(vdev->intx.mmap_timer);
321     vfio_intx_disable_kvm(vdev);
322     vfio_disable_irqindex(&vdev->vbasedev, VFIO_PCI_INTX_IRQ_INDEX);
323     vdev->intx.pending = false;
324     pci_irq_deassert(&vdev->pdev);
325     vfio_mmap_set_enabled(vdev, true);
326 
327     fd = event_notifier_get_fd(&vdev->intx.interrupt);
328     qemu_set_fd_handler(fd, NULL, NULL, vdev);
329     event_notifier_cleanup(&vdev->intx.interrupt);
330 
331     vdev->interrupt = VFIO_INT_NONE;
332 
333     trace_vfio_intx_disable(vdev->vbasedev.name);
334 }
335 
336 /*
337  * MSI/X
338  */
339 static void vfio_msi_interrupt(void *opaque)
340 {
341     VFIOMSIVector *vector = opaque;
342     VFIOPCIDevice *vdev = vector->vdev;
343     MSIMessage (*get_msg)(PCIDevice *dev, unsigned vector);
344     void (*notify)(PCIDevice *dev, unsigned vector);
345     MSIMessage msg;
346     int nr = vector - vdev->msi_vectors;
347 
348     if (!event_notifier_test_and_clear(&vector->interrupt)) {
349         return;
350     }
351 
352     if (vdev->interrupt == VFIO_INT_MSIX) {
353         get_msg = msix_get_message;
354         notify = msix_notify;
355 
356         /* A masked vector firing needs to use the PBA, enable it */
357         if (msix_is_masked(&vdev->pdev, nr)) {
358             set_bit(nr, vdev->msix->pending);
359             memory_region_set_enabled(&vdev->pdev.msix_pba_mmio, true);
360             trace_vfio_msix_pba_enable(vdev->vbasedev.name);
361         }
362     } else if (vdev->interrupt == VFIO_INT_MSI) {
363         get_msg = msi_get_message;
364         notify = msi_notify;
365     } else {
366         abort();
367     }
368 
369     msg = get_msg(&vdev->pdev, nr);
370     trace_vfio_msi_interrupt(vdev->vbasedev.name, nr, msg.address, msg.data);
371     notify(&vdev->pdev, nr);
372 }
373 
374 static int vfio_enable_vectors(VFIOPCIDevice *vdev, bool msix)
375 {
376     struct vfio_irq_set *irq_set;
377     int ret = 0, i, argsz;
378     int32_t *fds;
379 
380     argsz = sizeof(*irq_set) + (vdev->nr_vectors * sizeof(*fds));
381 
382     irq_set = g_malloc0(argsz);
383     irq_set->argsz = argsz;
384     irq_set->flags = VFIO_IRQ_SET_DATA_EVENTFD | VFIO_IRQ_SET_ACTION_TRIGGER;
385     irq_set->index = msix ? VFIO_PCI_MSIX_IRQ_INDEX : VFIO_PCI_MSI_IRQ_INDEX;
386     irq_set->start = 0;
387     irq_set->count = vdev->nr_vectors;
388     fds = (int32_t *)&irq_set->data;
389 
390     for (i = 0; i < vdev->nr_vectors; i++) {
391         int fd = -1;
392 
393         /*
394          * MSI vs MSI-X - The guest has direct access to MSI mask and pending
395          * bits, therefore we always use the KVM signaling path when setup.
396          * MSI-X mask and pending bits are emulated, so we want to use the
397          * KVM signaling path only when configured and unmasked.
398          */
399         if (vdev->msi_vectors[i].use) {
400             if (vdev->msi_vectors[i].virq < 0 ||
401                 (msix && msix_is_masked(&vdev->pdev, i))) {
402                 fd = event_notifier_get_fd(&vdev->msi_vectors[i].interrupt);
403             } else {
404                 fd = event_notifier_get_fd(&vdev->msi_vectors[i].kvm_interrupt);
405             }
406         }
407 
408         fds[i] = fd;
409     }
410 
411     ret = ioctl(vdev->vbasedev.fd, VFIO_DEVICE_SET_IRQS, irq_set);
412 
413     g_free(irq_set);
414 
415     return ret;
416 }
417 
418 static void vfio_add_kvm_msi_virq(VFIOPCIDevice *vdev, VFIOMSIVector *vector,
419                                   MSIMessage *msg, bool msix)
420 {
421     int virq;
422 
423     if ((msix && vdev->no_kvm_msix) || (!msix && vdev->no_kvm_msi) || !msg) {
424         return;
425     }
426 
427     if (event_notifier_init(&vector->kvm_interrupt, 0)) {
428         return;
429     }
430 
431     virq = kvm_irqchip_add_msi_route(kvm_state, *msg, &vdev->pdev);
432     if (virq < 0) {
433         event_notifier_cleanup(&vector->kvm_interrupt);
434         return;
435     }
436 
437     if (kvm_irqchip_add_irqfd_notifier_gsi(kvm_state, &vector->kvm_interrupt,
438                                        NULL, virq) < 0) {
439         kvm_irqchip_release_virq(kvm_state, virq);
440         event_notifier_cleanup(&vector->kvm_interrupt);
441         return;
442     }
443 
444     vector->virq = virq;
445 }
446 
447 static void vfio_remove_kvm_msi_virq(VFIOMSIVector *vector)
448 {
449     kvm_irqchip_remove_irqfd_notifier_gsi(kvm_state, &vector->kvm_interrupt,
450                                           vector->virq);
451     kvm_irqchip_release_virq(kvm_state, vector->virq);
452     vector->virq = -1;
453     event_notifier_cleanup(&vector->kvm_interrupt);
454 }
455 
456 static void vfio_update_kvm_msi_virq(VFIOMSIVector *vector, MSIMessage msg,
457                                      PCIDevice *pdev)
458 {
459     kvm_irqchip_update_msi_route(kvm_state, vector->virq, msg, pdev);
460 }
461 
462 static int vfio_msix_vector_do_use(PCIDevice *pdev, unsigned int nr,
463                                    MSIMessage *msg, IOHandler *handler)
464 {
465     VFIOPCIDevice *vdev = DO_UPCAST(VFIOPCIDevice, pdev, pdev);
466     VFIOMSIVector *vector;
467     int ret;
468 
469     trace_vfio_msix_vector_do_use(vdev->vbasedev.name, nr);
470 
471     vector = &vdev->msi_vectors[nr];
472 
473     if (!vector->use) {
474         vector->vdev = vdev;
475         vector->virq = -1;
476         if (event_notifier_init(&vector->interrupt, 0)) {
477             error_report("vfio: Error: event_notifier_init failed");
478         }
479         vector->use = true;
480         msix_vector_use(pdev, nr);
481     }
482 
483     qemu_set_fd_handler(event_notifier_get_fd(&vector->interrupt),
484                         handler, NULL, vector);
485 
486     /*
487      * Attempt to enable route through KVM irqchip,
488      * default to userspace handling if unavailable.
489      */
490     if (vector->virq >= 0) {
491         if (!msg) {
492             vfio_remove_kvm_msi_virq(vector);
493         } else {
494             vfio_update_kvm_msi_virq(vector, *msg, pdev);
495         }
496     } else {
497         vfio_add_kvm_msi_virq(vdev, vector, msg, true);
498     }
499 
500     /*
501      * We don't want to have the host allocate all possible MSI vectors
502      * for a device if they're not in use, so we shutdown and incrementally
503      * increase them as needed.
504      */
505     if (vdev->nr_vectors < nr + 1) {
506         vfio_disable_irqindex(&vdev->vbasedev, VFIO_PCI_MSIX_IRQ_INDEX);
507         vdev->nr_vectors = nr + 1;
508         ret = vfio_enable_vectors(vdev, true);
509         if (ret) {
510             error_report("vfio: failed to enable vectors, %d", ret);
511         }
512     } else {
513         int argsz;
514         struct vfio_irq_set *irq_set;
515         int32_t *pfd;
516 
517         argsz = sizeof(*irq_set) + sizeof(*pfd);
518 
519         irq_set = g_malloc0(argsz);
520         irq_set->argsz = argsz;
521         irq_set->flags = VFIO_IRQ_SET_DATA_EVENTFD |
522                          VFIO_IRQ_SET_ACTION_TRIGGER;
523         irq_set->index = VFIO_PCI_MSIX_IRQ_INDEX;
524         irq_set->start = nr;
525         irq_set->count = 1;
526         pfd = (int32_t *)&irq_set->data;
527 
528         if (vector->virq >= 0) {
529             *pfd = event_notifier_get_fd(&vector->kvm_interrupt);
530         } else {
531             *pfd = event_notifier_get_fd(&vector->interrupt);
532         }
533 
534         ret = ioctl(vdev->vbasedev.fd, VFIO_DEVICE_SET_IRQS, irq_set);
535         g_free(irq_set);
536         if (ret) {
537             error_report("vfio: failed to modify vector, %d", ret);
538         }
539     }
540 
541     /* Disable PBA emulation when nothing more is pending. */
542     clear_bit(nr, vdev->msix->pending);
543     if (find_first_bit(vdev->msix->pending,
544                        vdev->nr_vectors) == vdev->nr_vectors) {
545         memory_region_set_enabled(&vdev->pdev.msix_pba_mmio, false);
546         trace_vfio_msix_pba_disable(vdev->vbasedev.name);
547     }
548 
549     return 0;
550 }
551 
552 static int vfio_msix_vector_use(PCIDevice *pdev,
553                                 unsigned int nr, MSIMessage msg)
554 {
555     return vfio_msix_vector_do_use(pdev, nr, &msg, vfio_msi_interrupt);
556 }
557 
558 static void vfio_msix_vector_release(PCIDevice *pdev, unsigned int nr)
559 {
560     VFIOPCIDevice *vdev = DO_UPCAST(VFIOPCIDevice, pdev, pdev);
561     VFIOMSIVector *vector = &vdev->msi_vectors[nr];
562 
563     trace_vfio_msix_vector_release(vdev->vbasedev.name, nr);
564 
565     /*
566      * There are still old guests that mask and unmask vectors on every
567      * interrupt.  If we're using QEMU bypass with a KVM irqfd, leave all of
568      * the KVM setup in place, simply switch VFIO to use the non-bypass
569      * eventfd.  We'll then fire the interrupt through QEMU and the MSI-X
570      * core will mask the interrupt and set pending bits, allowing it to
571      * be re-asserted on unmask.  Nothing to do if already using QEMU mode.
572      */
573     if (vector->virq >= 0) {
574         int argsz;
575         struct vfio_irq_set *irq_set;
576         int32_t *pfd;
577 
578         argsz = sizeof(*irq_set) + sizeof(*pfd);
579 
580         irq_set = g_malloc0(argsz);
581         irq_set->argsz = argsz;
582         irq_set->flags = VFIO_IRQ_SET_DATA_EVENTFD |
583                          VFIO_IRQ_SET_ACTION_TRIGGER;
584         irq_set->index = VFIO_PCI_MSIX_IRQ_INDEX;
585         irq_set->start = nr;
586         irq_set->count = 1;
587         pfd = (int32_t *)&irq_set->data;
588 
589         *pfd = event_notifier_get_fd(&vector->interrupt);
590 
591         ioctl(vdev->vbasedev.fd, VFIO_DEVICE_SET_IRQS, irq_set);
592 
593         g_free(irq_set);
594     }
595 }
596 
597 static void vfio_msix_enable(VFIOPCIDevice *vdev)
598 {
599     vfio_disable_interrupts(vdev);
600 
601     vdev->msi_vectors = g_new0(VFIOMSIVector, vdev->msix->entries);
602 
603     vdev->interrupt = VFIO_INT_MSIX;
604 
605     /*
606      * Some communication channels between VF & PF or PF & fw rely on the
607      * physical state of the device and expect that enabling MSI-X from the
608      * guest enables the same on the host.  When our guest is Linux, the
609      * guest driver call to pci_enable_msix() sets the enabling bit in the
610      * MSI-X capability, but leaves the vector table masked.  We therefore
611      * can't rely on a vector_use callback (from request_irq() in the guest)
612      * to switch the physical device into MSI-X mode because that may come a
613      * long time after pci_enable_msix().  This code enables vector 0 with
614      * triggering to userspace, then immediately release the vector, leaving
615      * the physical device with no vectors enabled, but MSI-X enabled, just
616      * like the guest view.
617      */
618     vfio_msix_vector_do_use(&vdev->pdev, 0, NULL, NULL);
619     vfio_msix_vector_release(&vdev->pdev, 0);
620 
621     if (msix_set_vector_notifiers(&vdev->pdev, vfio_msix_vector_use,
622                                   vfio_msix_vector_release, NULL)) {
623         error_report("vfio: msix_set_vector_notifiers failed");
624     }
625 
626     trace_vfio_msix_enable(vdev->vbasedev.name);
627 }
628 
629 static void vfio_msi_enable(VFIOPCIDevice *vdev)
630 {
631     int ret, i;
632 
633     vfio_disable_interrupts(vdev);
634 
635     vdev->nr_vectors = msi_nr_vectors_allocated(&vdev->pdev);
636 retry:
637     vdev->msi_vectors = g_new0(VFIOMSIVector, vdev->nr_vectors);
638 
639     for (i = 0; i < vdev->nr_vectors; i++) {
640         VFIOMSIVector *vector = &vdev->msi_vectors[i];
641         MSIMessage msg = msi_get_message(&vdev->pdev, i);
642 
643         vector->vdev = vdev;
644         vector->virq = -1;
645         vector->use = true;
646 
647         if (event_notifier_init(&vector->interrupt, 0)) {
648             error_report("vfio: Error: event_notifier_init failed");
649         }
650 
651         qemu_set_fd_handler(event_notifier_get_fd(&vector->interrupt),
652                             vfio_msi_interrupt, NULL, vector);
653 
654         /*
655          * Attempt to enable route through KVM irqchip,
656          * default to userspace handling if unavailable.
657          */
658         vfio_add_kvm_msi_virq(vdev, vector, &msg, false);
659     }
660 
661     /* Set interrupt type prior to possible interrupts */
662     vdev->interrupt = VFIO_INT_MSI;
663 
664     ret = vfio_enable_vectors(vdev, false);
665     if (ret) {
666         if (ret < 0) {
667             error_report("vfio: Error: Failed to setup MSI fds: %m");
668         } else if (ret != vdev->nr_vectors) {
669             error_report("vfio: Error: Failed to enable %d "
670                          "MSI vectors, retry with %d", vdev->nr_vectors, ret);
671         }
672 
673         for (i = 0; i < vdev->nr_vectors; i++) {
674             VFIOMSIVector *vector = &vdev->msi_vectors[i];
675             if (vector->virq >= 0) {
676                 vfio_remove_kvm_msi_virq(vector);
677             }
678             qemu_set_fd_handler(event_notifier_get_fd(&vector->interrupt),
679                                 NULL, NULL, NULL);
680             event_notifier_cleanup(&vector->interrupt);
681         }
682 
683         g_free(vdev->msi_vectors);
684 
685         if (ret > 0 && ret != vdev->nr_vectors) {
686             vdev->nr_vectors = ret;
687             goto retry;
688         }
689         vdev->nr_vectors = 0;
690 
691         /*
692          * Failing to setup MSI doesn't really fall within any specification.
693          * Let's try leaving interrupts disabled and hope the guest figures
694          * out to fall back to INTx for this device.
695          */
696         error_report("vfio: Error: Failed to enable MSI");
697         vdev->interrupt = VFIO_INT_NONE;
698 
699         return;
700     }
701 
702     trace_vfio_msi_enable(vdev->vbasedev.name, vdev->nr_vectors);
703 }
704 
705 static void vfio_msi_disable_common(VFIOPCIDevice *vdev)
706 {
707     int i;
708 
709     for (i = 0; i < vdev->nr_vectors; i++) {
710         VFIOMSIVector *vector = &vdev->msi_vectors[i];
711         if (vdev->msi_vectors[i].use) {
712             if (vector->virq >= 0) {
713                 vfio_remove_kvm_msi_virq(vector);
714             }
715             qemu_set_fd_handler(event_notifier_get_fd(&vector->interrupt),
716                                 NULL, NULL, NULL);
717             event_notifier_cleanup(&vector->interrupt);
718         }
719     }
720 
721     g_free(vdev->msi_vectors);
722     vdev->msi_vectors = NULL;
723     vdev->nr_vectors = 0;
724     vdev->interrupt = VFIO_INT_NONE;
725 
726     vfio_intx_enable(vdev);
727 }
728 
729 static void vfio_msix_disable(VFIOPCIDevice *vdev)
730 {
731     int i;
732 
733     msix_unset_vector_notifiers(&vdev->pdev);
734 
735     /*
736      * MSI-X will only release vectors if MSI-X is still enabled on the
737      * device, check through the rest and release it ourselves if necessary.
738      */
739     for (i = 0; i < vdev->nr_vectors; i++) {
740         if (vdev->msi_vectors[i].use) {
741             vfio_msix_vector_release(&vdev->pdev, i);
742             msix_vector_unuse(&vdev->pdev, i);
743         }
744     }
745 
746     if (vdev->nr_vectors) {
747         vfio_disable_irqindex(&vdev->vbasedev, VFIO_PCI_MSIX_IRQ_INDEX);
748     }
749 
750     vfio_msi_disable_common(vdev);
751 
752     memset(vdev->msix->pending, 0,
753            BITS_TO_LONGS(vdev->msix->entries) * sizeof(unsigned long));
754 
755     trace_vfio_msix_disable(vdev->vbasedev.name);
756 }
757 
758 static void vfio_msi_disable(VFIOPCIDevice *vdev)
759 {
760     vfio_disable_irqindex(&vdev->vbasedev, VFIO_PCI_MSI_IRQ_INDEX);
761     vfio_msi_disable_common(vdev);
762 
763     trace_vfio_msi_disable(vdev->vbasedev.name);
764 }
765 
766 static void vfio_update_msi(VFIOPCIDevice *vdev)
767 {
768     int i;
769 
770     for (i = 0; i < vdev->nr_vectors; i++) {
771         VFIOMSIVector *vector = &vdev->msi_vectors[i];
772         MSIMessage msg;
773 
774         if (!vector->use || vector->virq < 0) {
775             continue;
776         }
777 
778         msg = msi_get_message(&vdev->pdev, i);
779         vfio_update_kvm_msi_virq(vector, msg, &vdev->pdev);
780     }
781 }
782 
783 static void vfio_pci_load_rom(VFIOPCIDevice *vdev)
784 {
785     struct vfio_region_info *reg_info;
786     uint64_t size;
787     off_t off = 0;
788     ssize_t bytes;
789 
790     if (vfio_get_region_info(&vdev->vbasedev,
791                              VFIO_PCI_ROM_REGION_INDEX, &reg_info)) {
792         error_report("vfio: Error getting ROM info: %m");
793         return;
794     }
795 
796     trace_vfio_pci_load_rom(vdev->vbasedev.name, (unsigned long)reg_info->size,
797                             (unsigned long)reg_info->offset,
798                             (unsigned long)reg_info->flags);
799 
800     vdev->rom_size = size = reg_info->size;
801     vdev->rom_offset = reg_info->offset;
802 
803     g_free(reg_info);
804 
805     if (!vdev->rom_size) {
806         vdev->rom_read_failed = true;
807         error_report("vfio-pci: Cannot read device rom at "
808                     "%s", vdev->vbasedev.name);
809         error_printf("Device option ROM contents are probably invalid "
810                     "(check dmesg).\nSkip option ROM probe with rombar=0, "
811                     "or load from file with romfile=\n");
812         return;
813     }
814 
815     vdev->rom = g_malloc(size);
816     memset(vdev->rom, 0xff, size);
817 
818     while (size) {
819         bytes = pread(vdev->vbasedev.fd, vdev->rom + off,
820                       size, vdev->rom_offset + off);
821         if (bytes == 0) {
822             break;
823         } else if (bytes > 0) {
824             off += bytes;
825             size -= bytes;
826         } else {
827             if (errno == EINTR || errno == EAGAIN) {
828                 continue;
829             }
830             error_report("vfio: Error reading device ROM: %m");
831             break;
832         }
833     }
834 
835     /*
836      * Test the ROM signature against our device, if the vendor is correct
837      * but the device ID doesn't match, store the correct device ID and
838      * recompute the checksum.  Intel IGD devices need this and are known
839      * to have bogus checksums so we can't simply adjust the checksum.
840      */
841     if (pci_get_word(vdev->rom) == 0xaa55 &&
842         pci_get_word(vdev->rom + 0x18) + 8 < vdev->rom_size &&
843         !memcmp(vdev->rom + pci_get_word(vdev->rom + 0x18), "PCIR", 4)) {
844         uint16_t vid, did;
845 
846         vid = pci_get_word(vdev->rom + pci_get_word(vdev->rom + 0x18) + 4);
847         did = pci_get_word(vdev->rom + pci_get_word(vdev->rom + 0x18) + 6);
848 
849         if (vid == vdev->vendor_id && did != vdev->device_id) {
850             int i;
851             uint8_t csum, *data = vdev->rom;
852 
853             pci_set_word(vdev->rom + pci_get_word(vdev->rom + 0x18) + 6,
854                          vdev->device_id);
855             data[6] = 0;
856 
857             for (csum = 0, i = 0; i < vdev->rom_size; i++) {
858                 csum += data[i];
859             }
860 
861             data[6] = -csum;
862         }
863     }
864 }
865 
866 static uint64_t vfio_rom_read(void *opaque, hwaddr addr, unsigned size)
867 {
868     VFIOPCIDevice *vdev = opaque;
869     union {
870         uint8_t byte;
871         uint16_t word;
872         uint32_t dword;
873         uint64_t qword;
874     } val;
875     uint64_t data = 0;
876 
877     /* Load the ROM lazily when the guest tries to read it */
878     if (unlikely(!vdev->rom && !vdev->rom_read_failed)) {
879         vfio_pci_load_rom(vdev);
880     }
881 
882     memcpy(&val, vdev->rom + addr,
883            (addr < vdev->rom_size) ? MIN(size, vdev->rom_size - addr) : 0);
884 
885     switch (size) {
886     case 1:
887         data = val.byte;
888         break;
889     case 2:
890         data = le16_to_cpu(val.word);
891         break;
892     case 4:
893         data = le32_to_cpu(val.dword);
894         break;
895     default:
896         hw_error("vfio: unsupported read size, %d bytes\n", size);
897         break;
898     }
899 
900     trace_vfio_rom_read(vdev->vbasedev.name, addr, size, data);
901 
902     return data;
903 }
904 
905 static void vfio_rom_write(void *opaque, hwaddr addr,
906                            uint64_t data, unsigned size)
907 {
908 }
909 
910 static const MemoryRegionOps vfio_rom_ops = {
911     .read = vfio_rom_read,
912     .write = vfio_rom_write,
913     .endianness = DEVICE_LITTLE_ENDIAN,
914 };
915 
916 static void vfio_pci_size_rom(VFIOPCIDevice *vdev)
917 {
918     uint32_t orig, size = cpu_to_le32((uint32_t)PCI_ROM_ADDRESS_MASK);
919     off_t offset = vdev->config_offset + PCI_ROM_ADDRESS;
920     DeviceState *dev = DEVICE(vdev);
921     char *name;
922     int fd = vdev->vbasedev.fd;
923 
924     if (vdev->pdev.romfile || !vdev->pdev.rom_bar) {
925         /* Since pci handles romfile, just print a message and return */
926         if (vfio_blacklist_opt_rom(vdev) && vdev->pdev.romfile) {
927             error_printf("Warning : Device at %s is known to cause system instability issues during option rom execution. Proceeding anyway since user specified romfile\n",
928                          vdev->vbasedev.name);
929         }
930         return;
931     }
932 
933     /*
934      * Use the same size ROM BAR as the physical device.  The contents
935      * will get filled in later when the guest tries to read it.
936      */
937     if (pread(fd, &orig, 4, offset) != 4 ||
938         pwrite(fd, &size, 4, offset) != 4 ||
939         pread(fd, &size, 4, offset) != 4 ||
940         pwrite(fd, &orig, 4, offset) != 4) {
941         error_report("%s(%s) failed: %m", __func__, vdev->vbasedev.name);
942         return;
943     }
944 
945     size = ~(le32_to_cpu(size) & PCI_ROM_ADDRESS_MASK) + 1;
946 
947     if (!size) {
948         return;
949     }
950 
951     if (vfio_blacklist_opt_rom(vdev)) {
952         if (dev->opts && qemu_opt_get(dev->opts, "rombar")) {
953             error_printf("Warning : Device at %s is known to cause system instability issues during option rom execution. Proceeding anyway since user specified non zero value for rombar\n",
954                          vdev->vbasedev.name);
955         } else {
956             error_printf("Warning : Rom loading for device at %s has been disabled due to system instability issues. Specify rombar=1 or romfile to force\n",
957                          vdev->vbasedev.name);
958             return;
959         }
960     }
961 
962     trace_vfio_pci_size_rom(vdev->vbasedev.name, size);
963 
964     name = g_strdup_printf("vfio[%s].rom", vdev->vbasedev.name);
965 
966     memory_region_init_io(&vdev->pdev.rom, OBJECT(vdev),
967                           &vfio_rom_ops, vdev, name, size);
968     g_free(name);
969 
970     pci_register_bar(&vdev->pdev, PCI_ROM_SLOT,
971                      PCI_BASE_ADDRESS_SPACE_MEMORY, &vdev->pdev.rom);
972 
973     vdev->pdev.has_rom = true;
974     vdev->rom_read_failed = false;
975 }
976 
977 void vfio_vga_write(void *opaque, hwaddr addr,
978                            uint64_t data, unsigned size)
979 {
980     VFIOVGARegion *region = opaque;
981     VFIOVGA *vga = container_of(region, VFIOVGA, region[region->nr]);
982     union {
983         uint8_t byte;
984         uint16_t word;
985         uint32_t dword;
986         uint64_t qword;
987     } buf;
988     off_t offset = vga->fd_offset + region->offset + addr;
989 
990     switch (size) {
991     case 1:
992         buf.byte = data;
993         break;
994     case 2:
995         buf.word = cpu_to_le16(data);
996         break;
997     case 4:
998         buf.dword = cpu_to_le32(data);
999         break;
1000     default:
1001         hw_error("vfio: unsupported write size, %d bytes", size);
1002         break;
1003     }
1004 
1005     if (pwrite(vga->fd, &buf, size, offset) != size) {
1006         error_report("%s(,0x%"HWADDR_PRIx", 0x%"PRIx64", %d) failed: %m",
1007                      __func__, region->offset + addr, data, size);
1008     }
1009 
1010     trace_vfio_vga_write(region->offset + addr, data, size);
1011 }
1012 
1013 uint64_t vfio_vga_read(void *opaque, hwaddr addr, unsigned size)
1014 {
1015     VFIOVGARegion *region = opaque;
1016     VFIOVGA *vga = container_of(region, VFIOVGA, region[region->nr]);
1017     union {
1018         uint8_t byte;
1019         uint16_t word;
1020         uint32_t dword;
1021         uint64_t qword;
1022     } buf;
1023     uint64_t data = 0;
1024     off_t offset = vga->fd_offset + region->offset + addr;
1025 
1026     if (pread(vga->fd, &buf, size, offset) != size) {
1027         error_report("%s(,0x%"HWADDR_PRIx", %d) failed: %m",
1028                      __func__, region->offset + addr, size);
1029         return (uint64_t)-1;
1030     }
1031 
1032     switch (size) {
1033     case 1:
1034         data = buf.byte;
1035         break;
1036     case 2:
1037         data = le16_to_cpu(buf.word);
1038         break;
1039     case 4:
1040         data = le32_to_cpu(buf.dword);
1041         break;
1042     default:
1043         hw_error("vfio: unsupported read size, %d bytes", size);
1044         break;
1045     }
1046 
1047     trace_vfio_vga_read(region->offset + addr, size, data);
1048 
1049     return data;
1050 }
1051 
1052 static const MemoryRegionOps vfio_vga_ops = {
1053     .read = vfio_vga_read,
1054     .write = vfio_vga_write,
1055     .endianness = DEVICE_LITTLE_ENDIAN,
1056 };
1057 
1058 /*
1059  * PCI config space
1060  */
1061 uint32_t vfio_pci_read_config(PCIDevice *pdev, uint32_t addr, int len)
1062 {
1063     VFIOPCIDevice *vdev = DO_UPCAST(VFIOPCIDevice, pdev, pdev);
1064     uint32_t emu_bits = 0, emu_val = 0, phys_val = 0, val;
1065 
1066     memcpy(&emu_bits, vdev->emulated_config_bits + addr, len);
1067     emu_bits = le32_to_cpu(emu_bits);
1068 
1069     if (emu_bits) {
1070         emu_val = pci_default_read_config(pdev, addr, len);
1071     }
1072 
1073     if (~emu_bits & (0xffffffffU >> (32 - len * 8))) {
1074         ssize_t ret;
1075 
1076         ret = pread(vdev->vbasedev.fd, &phys_val, len,
1077                     vdev->config_offset + addr);
1078         if (ret != len) {
1079             error_report("%s(%s, 0x%x, 0x%x) failed: %m",
1080                          __func__, vdev->vbasedev.name, addr, len);
1081             return -errno;
1082         }
1083         phys_val = le32_to_cpu(phys_val);
1084     }
1085 
1086     val = (emu_val & emu_bits) | (phys_val & ~emu_bits);
1087 
1088     trace_vfio_pci_read_config(vdev->vbasedev.name, addr, len, val);
1089 
1090     return val;
1091 }
1092 
1093 void vfio_pci_write_config(PCIDevice *pdev,
1094                            uint32_t addr, uint32_t val, int len)
1095 {
1096     VFIOPCIDevice *vdev = DO_UPCAST(VFIOPCIDevice, pdev, pdev);
1097     uint32_t val_le = cpu_to_le32(val);
1098 
1099     trace_vfio_pci_write_config(vdev->vbasedev.name, addr, val, len);
1100 
1101     /* Write everything to VFIO, let it filter out what we can't write */
1102     if (pwrite(vdev->vbasedev.fd, &val_le, len, vdev->config_offset + addr)
1103                 != len) {
1104         error_report("%s(%s, 0x%x, 0x%x, 0x%x) failed: %m",
1105                      __func__, vdev->vbasedev.name, addr, val, len);
1106     }
1107 
1108     /* MSI/MSI-X Enabling/Disabling */
1109     if (pdev->cap_present & QEMU_PCI_CAP_MSI &&
1110         ranges_overlap(addr, len, pdev->msi_cap, vdev->msi_cap_size)) {
1111         int is_enabled, was_enabled = msi_enabled(pdev);
1112 
1113         pci_default_write_config(pdev, addr, val, len);
1114 
1115         is_enabled = msi_enabled(pdev);
1116 
1117         if (!was_enabled) {
1118             if (is_enabled) {
1119                 vfio_msi_enable(vdev);
1120             }
1121         } else {
1122             if (!is_enabled) {
1123                 vfio_msi_disable(vdev);
1124             } else {
1125                 vfio_update_msi(vdev);
1126             }
1127         }
1128     } else if (pdev->cap_present & QEMU_PCI_CAP_MSIX &&
1129         ranges_overlap(addr, len, pdev->msix_cap, MSIX_CAP_LENGTH)) {
1130         int is_enabled, was_enabled = msix_enabled(pdev);
1131 
1132         pci_default_write_config(pdev, addr, val, len);
1133 
1134         is_enabled = msix_enabled(pdev);
1135 
1136         if (!was_enabled && is_enabled) {
1137             vfio_msix_enable(vdev);
1138         } else if (was_enabled && !is_enabled) {
1139             vfio_msix_disable(vdev);
1140         }
1141     } else {
1142         /* Write everything to QEMU to keep emulated bits correct */
1143         pci_default_write_config(pdev, addr, val, len);
1144     }
1145 }
1146 
1147 /*
1148  * Interrupt setup
1149  */
1150 static void vfio_disable_interrupts(VFIOPCIDevice *vdev)
1151 {
1152     /*
1153      * More complicated than it looks.  Disabling MSI/X transitions the
1154      * device to INTx mode (if supported).  Therefore we need to first
1155      * disable MSI/X and then cleanup by disabling INTx.
1156      */
1157     if (vdev->interrupt == VFIO_INT_MSIX) {
1158         vfio_msix_disable(vdev);
1159     } else if (vdev->interrupt == VFIO_INT_MSI) {
1160         vfio_msi_disable(vdev);
1161     }
1162 
1163     if (vdev->interrupt == VFIO_INT_INTx) {
1164         vfio_intx_disable(vdev);
1165     }
1166 }
1167 
1168 static int vfio_msi_setup(VFIOPCIDevice *vdev, int pos)
1169 {
1170     uint16_t ctrl;
1171     bool msi_64bit, msi_maskbit;
1172     int ret, entries;
1173 
1174     if (pread(vdev->vbasedev.fd, &ctrl, sizeof(ctrl),
1175               vdev->config_offset + pos + PCI_CAP_FLAGS) != sizeof(ctrl)) {
1176         return -errno;
1177     }
1178     ctrl = le16_to_cpu(ctrl);
1179 
1180     msi_64bit = !!(ctrl & PCI_MSI_FLAGS_64BIT);
1181     msi_maskbit = !!(ctrl & PCI_MSI_FLAGS_MASKBIT);
1182     entries = 1 << ((ctrl & PCI_MSI_FLAGS_QMASK) >> 1);
1183 
1184     trace_vfio_msi_setup(vdev->vbasedev.name, pos);
1185 
1186     ret = msi_init(&vdev->pdev, pos, entries, msi_64bit, msi_maskbit);
1187     if (ret < 0) {
1188         if (ret == -ENOTSUP) {
1189             return 0;
1190         }
1191         error_report("vfio: msi_init failed");
1192         return ret;
1193     }
1194     vdev->msi_cap_size = 0xa + (msi_maskbit ? 0xa : 0) + (msi_64bit ? 0x4 : 0);
1195 
1196     return 0;
1197 }
1198 
1199 static void vfio_pci_fixup_msix_region(VFIOPCIDevice *vdev)
1200 {
1201     off_t start, end;
1202     VFIORegion *region = &vdev->bars[vdev->msix->table_bar].region;
1203 
1204     /*
1205      * We expect to find a single mmap covering the whole BAR, anything else
1206      * means it's either unsupported or already setup.
1207      */
1208     if (region->nr_mmaps != 1 || region->mmaps[0].offset ||
1209         region->size != region->mmaps[0].size) {
1210         return;
1211     }
1212 
1213     /* MSI-X table start and end aligned to host page size */
1214     start = vdev->msix->table_offset & qemu_real_host_page_mask;
1215     end = REAL_HOST_PAGE_ALIGN((uint64_t)vdev->msix->table_offset +
1216                                (vdev->msix->entries * PCI_MSIX_ENTRY_SIZE));
1217 
1218     /*
1219      * Does the MSI-X table cover the beginning of the BAR?  The whole BAR?
1220      * NB - Host page size is necessarily a power of two and so is the PCI
1221      * BAR (not counting EA yet), therefore if we have host page aligned
1222      * @start and @end, then any remainder of the BAR before or after those
1223      * must be at least host page sized and therefore mmap'able.
1224      */
1225     if (!start) {
1226         if (end >= region->size) {
1227             region->nr_mmaps = 0;
1228             g_free(region->mmaps);
1229             region->mmaps = NULL;
1230             trace_vfio_msix_fixup(vdev->vbasedev.name,
1231                                   vdev->msix->table_bar, 0, 0);
1232         } else {
1233             region->mmaps[0].offset = end;
1234             region->mmaps[0].size = region->size - end;
1235             trace_vfio_msix_fixup(vdev->vbasedev.name,
1236                               vdev->msix->table_bar, region->mmaps[0].offset,
1237                               region->mmaps[0].offset + region->mmaps[0].size);
1238         }
1239 
1240     /* Maybe it's aligned at the end of the BAR */
1241     } else if (end >= region->size) {
1242         region->mmaps[0].size = start;
1243         trace_vfio_msix_fixup(vdev->vbasedev.name,
1244                               vdev->msix->table_bar, region->mmaps[0].offset,
1245                               region->mmaps[0].offset + region->mmaps[0].size);
1246 
1247     /* Otherwise it must split the BAR */
1248     } else {
1249         region->nr_mmaps = 2;
1250         region->mmaps = g_renew(VFIOMmap, region->mmaps, 2);
1251 
1252         memcpy(&region->mmaps[1], &region->mmaps[0], sizeof(VFIOMmap));
1253 
1254         region->mmaps[0].size = start;
1255         trace_vfio_msix_fixup(vdev->vbasedev.name,
1256                               vdev->msix->table_bar, region->mmaps[0].offset,
1257                               region->mmaps[0].offset + region->mmaps[0].size);
1258 
1259         region->mmaps[1].offset = end;
1260         region->mmaps[1].size = region->size - end;
1261         trace_vfio_msix_fixup(vdev->vbasedev.name,
1262                               vdev->msix->table_bar, region->mmaps[1].offset,
1263                               region->mmaps[1].offset + region->mmaps[1].size);
1264     }
1265 }
1266 
1267 /*
1268  * We don't have any control over how pci_add_capability() inserts
1269  * capabilities into the chain.  In order to setup MSI-X we need a
1270  * MemoryRegion for the BAR.  In order to setup the BAR and not
1271  * attempt to mmap the MSI-X table area, which VFIO won't allow, we
1272  * need to first look for where the MSI-X table lives.  So we
1273  * unfortunately split MSI-X setup across two functions.
1274  */
1275 static int vfio_msix_early_setup(VFIOPCIDevice *vdev)
1276 {
1277     uint8_t pos;
1278     uint16_t ctrl;
1279     uint32_t table, pba;
1280     int fd = vdev->vbasedev.fd;
1281     VFIOMSIXInfo *msix;
1282 
1283     pos = pci_find_capability(&vdev->pdev, PCI_CAP_ID_MSIX);
1284     if (!pos) {
1285         return 0;
1286     }
1287 
1288     if (pread(fd, &ctrl, sizeof(ctrl),
1289               vdev->config_offset + pos + PCI_MSIX_FLAGS) != sizeof(ctrl)) {
1290         return -errno;
1291     }
1292 
1293     if (pread(fd, &table, sizeof(table),
1294               vdev->config_offset + pos + PCI_MSIX_TABLE) != sizeof(table)) {
1295         return -errno;
1296     }
1297 
1298     if (pread(fd, &pba, sizeof(pba),
1299               vdev->config_offset + pos + PCI_MSIX_PBA) != sizeof(pba)) {
1300         return -errno;
1301     }
1302 
1303     ctrl = le16_to_cpu(ctrl);
1304     table = le32_to_cpu(table);
1305     pba = le32_to_cpu(pba);
1306 
1307     msix = g_malloc0(sizeof(*msix));
1308     msix->table_bar = table & PCI_MSIX_FLAGS_BIRMASK;
1309     msix->table_offset = table & ~PCI_MSIX_FLAGS_BIRMASK;
1310     msix->pba_bar = pba & PCI_MSIX_FLAGS_BIRMASK;
1311     msix->pba_offset = pba & ~PCI_MSIX_FLAGS_BIRMASK;
1312     msix->entries = (ctrl & PCI_MSIX_FLAGS_QSIZE) + 1;
1313 
1314     /*
1315      * Test the size of the pba_offset variable and catch if it extends outside
1316      * of the specified BAR. If it is the case, we need to apply a hardware
1317      * specific quirk if the device is known or we have a broken configuration.
1318      */
1319     if (msix->pba_offset >= vdev->bars[msix->pba_bar].region.size) {
1320         /*
1321          * Chelsio T5 Virtual Function devices are encoded as 0x58xx for T5
1322          * adapters. The T5 hardware returns an incorrect value of 0x8000 for
1323          * the VF PBA offset while the BAR itself is only 8k. The correct value
1324          * is 0x1000, so we hard code that here.
1325          */
1326         if (vdev->vendor_id == PCI_VENDOR_ID_CHELSIO &&
1327             (vdev->device_id & 0xff00) == 0x5800) {
1328             msix->pba_offset = 0x1000;
1329         } else {
1330             error_report("vfio: Hardware reports invalid configuration, "
1331                          "MSIX PBA outside of specified BAR");
1332             g_free(msix);
1333             return -EINVAL;
1334         }
1335     }
1336 
1337     trace_vfio_msix_early_setup(vdev->vbasedev.name, pos, msix->table_bar,
1338                                 msix->table_offset, msix->entries);
1339     vdev->msix = msix;
1340 
1341     vfio_pci_fixup_msix_region(vdev);
1342 
1343     return 0;
1344 }
1345 
1346 static int vfio_msix_setup(VFIOPCIDevice *vdev, int pos)
1347 {
1348     int ret;
1349 
1350     vdev->msix->pending = g_malloc0(BITS_TO_LONGS(vdev->msix->entries) *
1351                                     sizeof(unsigned long));
1352     ret = msix_init(&vdev->pdev, vdev->msix->entries,
1353                     vdev->bars[vdev->msix->table_bar].region.mem,
1354                     vdev->msix->table_bar, vdev->msix->table_offset,
1355                     vdev->bars[vdev->msix->pba_bar].region.mem,
1356                     vdev->msix->pba_bar, vdev->msix->pba_offset, pos);
1357     if (ret < 0) {
1358         if (ret == -ENOTSUP) {
1359             return 0;
1360         }
1361         error_report("vfio: msix_init failed");
1362         return ret;
1363     }
1364 
1365     /*
1366      * The PCI spec suggests that devices provide additional alignment for
1367      * MSI-X structures and avoid overlapping non-MSI-X related registers.
1368      * For an assigned device, this hopefully means that emulation of MSI-X
1369      * structures does not affect the performance of the device.  If devices
1370      * fail to provide that alignment, a significant performance penalty may
1371      * result, for instance Mellanox MT27500 VFs:
1372      * http://www.spinics.net/lists/kvm/msg125881.html
1373      *
1374      * The PBA is simply not that important for such a serious regression and
1375      * most drivers do not appear to look at it.  The solution for this is to
1376      * disable the PBA MemoryRegion unless it's being used.  We disable it
1377      * here and only enable it if a masked vector fires through QEMU.  As the
1378      * vector-use notifier is called, which occurs on unmask, we test whether
1379      * PBA emulation is needed and again disable if not.
1380      */
1381     memory_region_set_enabled(&vdev->pdev.msix_pba_mmio, false);
1382 
1383     return 0;
1384 }
1385 
1386 static void vfio_teardown_msi(VFIOPCIDevice *vdev)
1387 {
1388     msi_uninit(&vdev->pdev);
1389 
1390     if (vdev->msix) {
1391         msix_uninit(&vdev->pdev,
1392                     vdev->bars[vdev->msix->table_bar].region.mem,
1393                     vdev->bars[vdev->msix->pba_bar].region.mem);
1394         g_free(vdev->msix->pending);
1395     }
1396 }
1397 
1398 /*
1399  * Resource setup
1400  */
1401 static void vfio_mmap_set_enabled(VFIOPCIDevice *vdev, bool enabled)
1402 {
1403     int i;
1404 
1405     for (i = 0; i < PCI_ROM_SLOT; i++) {
1406         vfio_region_mmaps_set_enabled(&vdev->bars[i].region, enabled);
1407     }
1408 }
1409 
1410 static void vfio_bar_setup(VFIOPCIDevice *vdev, int nr)
1411 {
1412     VFIOBAR *bar = &vdev->bars[nr];
1413 
1414     uint32_t pci_bar;
1415     uint8_t type;
1416     int ret;
1417 
1418     /* Skip both unimplemented BARs and the upper half of 64bit BARS. */
1419     if (!bar->region.size) {
1420         return;
1421     }
1422 
1423     /* Determine what type of BAR this is for registration */
1424     ret = pread(vdev->vbasedev.fd, &pci_bar, sizeof(pci_bar),
1425                 vdev->config_offset + PCI_BASE_ADDRESS_0 + (4 * nr));
1426     if (ret != sizeof(pci_bar)) {
1427         error_report("vfio: Failed to read BAR %d (%m)", nr);
1428         return;
1429     }
1430 
1431     pci_bar = le32_to_cpu(pci_bar);
1432     bar->ioport = (pci_bar & PCI_BASE_ADDRESS_SPACE_IO);
1433     bar->mem64 = bar->ioport ? 0 : (pci_bar & PCI_BASE_ADDRESS_MEM_TYPE_64);
1434     type = pci_bar & (bar->ioport ? ~PCI_BASE_ADDRESS_IO_MASK :
1435                                     ~PCI_BASE_ADDRESS_MEM_MASK);
1436 
1437     if (vfio_region_mmap(&bar->region)) {
1438         error_report("Failed to mmap %s BAR %d. Performance may be slow",
1439                      vdev->vbasedev.name, nr);
1440     }
1441 
1442     pci_register_bar(&vdev->pdev, nr, type, bar->region.mem);
1443 }
1444 
1445 static void vfio_bars_setup(VFIOPCIDevice *vdev)
1446 {
1447     int i;
1448 
1449     for (i = 0; i < PCI_ROM_SLOT; i++) {
1450         vfio_bar_setup(vdev, i);
1451     }
1452 }
1453 
1454 static void vfio_bars_exit(VFIOPCIDevice *vdev)
1455 {
1456     int i;
1457 
1458     for (i = 0; i < PCI_ROM_SLOT; i++) {
1459         vfio_bar_quirk_exit(vdev, i);
1460         vfio_region_exit(&vdev->bars[i].region);
1461     }
1462 
1463     if (vdev->vga) {
1464         pci_unregister_vga(&vdev->pdev);
1465         vfio_vga_quirk_exit(vdev);
1466     }
1467 }
1468 
1469 static void vfio_bars_finalize(VFIOPCIDevice *vdev)
1470 {
1471     int i;
1472 
1473     for (i = 0; i < PCI_ROM_SLOT; i++) {
1474         vfio_bar_quirk_finalize(vdev, i);
1475         vfio_region_finalize(&vdev->bars[i].region);
1476     }
1477 
1478     if (vdev->vga) {
1479         vfio_vga_quirk_finalize(vdev);
1480         for (i = 0; i < ARRAY_SIZE(vdev->vga->region); i++) {
1481             object_unparent(OBJECT(&vdev->vga->region[i].mem));
1482         }
1483         g_free(vdev->vga);
1484     }
1485 }
1486 
1487 /*
1488  * General setup
1489  */
1490 static uint8_t vfio_std_cap_max_size(PCIDevice *pdev, uint8_t pos)
1491 {
1492     uint8_t tmp;
1493     uint16_t next = PCI_CONFIG_SPACE_SIZE;
1494 
1495     for (tmp = pdev->config[PCI_CAPABILITY_LIST]; tmp;
1496          tmp = pdev->config[tmp + PCI_CAP_LIST_NEXT]) {
1497         if (tmp > pos && tmp < next) {
1498             next = tmp;
1499         }
1500     }
1501 
1502     return next - pos;
1503 }
1504 
1505 static void vfio_set_word_bits(uint8_t *buf, uint16_t val, uint16_t mask)
1506 {
1507     pci_set_word(buf, (pci_get_word(buf) & ~mask) | val);
1508 }
1509 
1510 static void vfio_add_emulated_word(VFIOPCIDevice *vdev, int pos,
1511                                    uint16_t val, uint16_t mask)
1512 {
1513     vfio_set_word_bits(vdev->pdev.config + pos, val, mask);
1514     vfio_set_word_bits(vdev->pdev.wmask + pos, ~mask, mask);
1515     vfio_set_word_bits(vdev->emulated_config_bits + pos, mask, mask);
1516 }
1517 
1518 static void vfio_set_long_bits(uint8_t *buf, uint32_t val, uint32_t mask)
1519 {
1520     pci_set_long(buf, (pci_get_long(buf) & ~mask) | val);
1521 }
1522 
1523 static void vfio_add_emulated_long(VFIOPCIDevice *vdev, int pos,
1524                                    uint32_t val, uint32_t mask)
1525 {
1526     vfio_set_long_bits(vdev->pdev.config + pos, val, mask);
1527     vfio_set_long_bits(vdev->pdev.wmask + pos, ~mask, mask);
1528     vfio_set_long_bits(vdev->emulated_config_bits + pos, mask, mask);
1529 }
1530 
1531 static int vfio_setup_pcie_cap(VFIOPCIDevice *vdev, int pos, uint8_t size)
1532 {
1533     uint16_t flags;
1534     uint8_t type;
1535 
1536     flags = pci_get_word(vdev->pdev.config + pos + PCI_CAP_FLAGS);
1537     type = (flags & PCI_EXP_FLAGS_TYPE) >> 4;
1538 
1539     if (type != PCI_EXP_TYPE_ENDPOINT &&
1540         type != PCI_EXP_TYPE_LEG_END &&
1541         type != PCI_EXP_TYPE_RC_END) {
1542 
1543         error_report("vfio: Assignment of PCIe type 0x%x "
1544                      "devices is not currently supported", type);
1545         return -EINVAL;
1546     }
1547 
1548     if (!pci_bus_is_express(vdev->pdev.bus)) {
1549         PCIBus *bus = vdev->pdev.bus;
1550         PCIDevice *bridge;
1551 
1552         /*
1553          * Traditionally PCI device assignment exposes the PCIe capability
1554          * as-is on non-express buses.  The reason being that some drivers
1555          * simply assume that it's there, for example tg3.  However when
1556          * we're running on a native PCIe machine type, like Q35, we need
1557          * to hide the PCIe capability.  The reason for this is twofold;
1558          * first Windows guests get a Code 10 error when the PCIe capability
1559          * is exposed in this configuration.  Therefore express devices won't
1560          * work at all unless they're attached to express buses in the VM.
1561          * Second, a native PCIe machine introduces the possibility of fine
1562          * granularity IOMMUs supporting both translation and isolation.
1563          * Guest code to discover the IOMMU visibility of a device, such as
1564          * IOMMU grouping code on Linux, is very aware of device types and
1565          * valid transitions between bus types.  An express device on a non-
1566          * express bus is not a valid combination on bare metal systems.
1567          *
1568          * Drivers that require a PCIe capability to make the device
1569          * functional are simply going to need to have their devices placed
1570          * on a PCIe bus in the VM.
1571          */
1572         while (!pci_bus_is_root(bus)) {
1573             bridge = pci_bridge_get_device(bus);
1574             bus = bridge->bus;
1575         }
1576 
1577         if (pci_bus_is_express(bus)) {
1578             return 0;
1579         }
1580 
1581     } else if (pci_bus_is_root(vdev->pdev.bus)) {
1582         /*
1583          * On a Root Complex bus Endpoints become Root Complex Integrated
1584          * Endpoints, which changes the type and clears the LNK & LNK2 fields.
1585          */
1586         if (type == PCI_EXP_TYPE_ENDPOINT) {
1587             vfio_add_emulated_word(vdev, pos + PCI_CAP_FLAGS,
1588                                    PCI_EXP_TYPE_RC_END << 4,
1589                                    PCI_EXP_FLAGS_TYPE);
1590 
1591             /* Link Capabilities, Status, and Control goes away */
1592             if (size > PCI_EXP_LNKCTL) {
1593                 vfio_add_emulated_long(vdev, pos + PCI_EXP_LNKCAP, 0, ~0);
1594                 vfio_add_emulated_word(vdev, pos + PCI_EXP_LNKCTL, 0, ~0);
1595                 vfio_add_emulated_word(vdev, pos + PCI_EXP_LNKSTA, 0, ~0);
1596 
1597 #ifndef PCI_EXP_LNKCAP2
1598 #define PCI_EXP_LNKCAP2 44
1599 #endif
1600 #ifndef PCI_EXP_LNKSTA2
1601 #define PCI_EXP_LNKSTA2 50
1602 #endif
1603                 /* Link 2 Capabilities, Status, and Control goes away */
1604                 if (size > PCI_EXP_LNKCAP2) {
1605                     vfio_add_emulated_long(vdev, pos + PCI_EXP_LNKCAP2, 0, ~0);
1606                     vfio_add_emulated_word(vdev, pos + PCI_EXP_LNKCTL2, 0, ~0);
1607                     vfio_add_emulated_word(vdev, pos + PCI_EXP_LNKSTA2, 0, ~0);
1608                 }
1609             }
1610 
1611         } else if (type == PCI_EXP_TYPE_LEG_END) {
1612             /*
1613              * Legacy endpoints don't belong on the root complex.  Windows
1614              * seems to be happier with devices if we skip the capability.
1615              */
1616             return 0;
1617         }
1618 
1619     } else {
1620         /*
1621          * Convert Root Complex Integrated Endpoints to regular endpoints.
1622          * These devices don't support LNK/LNK2 capabilities, so make them up.
1623          */
1624         if (type == PCI_EXP_TYPE_RC_END) {
1625             vfio_add_emulated_word(vdev, pos + PCI_CAP_FLAGS,
1626                                    PCI_EXP_TYPE_ENDPOINT << 4,
1627                                    PCI_EXP_FLAGS_TYPE);
1628             vfio_add_emulated_long(vdev, pos + PCI_EXP_LNKCAP,
1629                                    PCI_EXP_LNK_MLW_1 | PCI_EXP_LNK_LS_25, ~0);
1630             vfio_add_emulated_word(vdev, pos + PCI_EXP_LNKCTL, 0, ~0);
1631         }
1632 
1633         /* Mark the Link Status bits as emulated to allow virtual negotiation */
1634         vfio_add_emulated_word(vdev, pos + PCI_EXP_LNKSTA,
1635                                pci_get_word(vdev->pdev.config + pos +
1636                                             PCI_EXP_LNKSTA),
1637                                PCI_EXP_LNKCAP_MLW | PCI_EXP_LNKCAP_SLS);
1638     }
1639 
1640     pos = pci_add_capability(&vdev->pdev, PCI_CAP_ID_EXP, pos, size);
1641     if (pos >= 0) {
1642         vdev->pdev.exp.exp_cap = pos;
1643     }
1644 
1645     return pos;
1646 }
1647 
1648 static void vfio_check_pcie_flr(VFIOPCIDevice *vdev, uint8_t pos)
1649 {
1650     uint32_t cap = pci_get_long(vdev->pdev.config + pos + PCI_EXP_DEVCAP);
1651 
1652     if (cap & PCI_EXP_DEVCAP_FLR) {
1653         trace_vfio_check_pcie_flr(vdev->vbasedev.name);
1654         vdev->has_flr = true;
1655     }
1656 }
1657 
1658 static void vfio_check_pm_reset(VFIOPCIDevice *vdev, uint8_t pos)
1659 {
1660     uint16_t csr = pci_get_word(vdev->pdev.config + pos + PCI_PM_CTRL);
1661 
1662     if (!(csr & PCI_PM_CTRL_NO_SOFT_RESET)) {
1663         trace_vfio_check_pm_reset(vdev->vbasedev.name);
1664         vdev->has_pm_reset = true;
1665     }
1666 }
1667 
1668 static void vfio_check_af_flr(VFIOPCIDevice *vdev, uint8_t pos)
1669 {
1670     uint8_t cap = pci_get_byte(vdev->pdev.config + pos + PCI_AF_CAP);
1671 
1672     if ((cap & PCI_AF_CAP_TP) && (cap & PCI_AF_CAP_FLR)) {
1673         trace_vfio_check_af_flr(vdev->vbasedev.name);
1674         vdev->has_flr = true;
1675     }
1676 }
1677 
1678 static int vfio_add_std_cap(VFIOPCIDevice *vdev, uint8_t pos)
1679 {
1680     PCIDevice *pdev = &vdev->pdev;
1681     uint8_t cap_id, next, size;
1682     int ret;
1683 
1684     cap_id = pdev->config[pos];
1685     next = pdev->config[pos + PCI_CAP_LIST_NEXT];
1686 
1687     /*
1688      * If it becomes important to configure capabilities to their actual
1689      * size, use this as the default when it's something we don't recognize.
1690      * Since QEMU doesn't actually handle many of the config accesses,
1691      * exact size doesn't seem worthwhile.
1692      */
1693     size = vfio_std_cap_max_size(pdev, pos);
1694 
1695     /*
1696      * pci_add_capability always inserts the new capability at the head
1697      * of the chain.  Therefore to end up with a chain that matches the
1698      * physical device, we insert from the end by making this recursive.
1699      * This is also why we pre-calculate size above as cached config space
1700      * will be changed as we unwind the stack.
1701      */
1702     if (next) {
1703         ret = vfio_add_std_cap(vdev, next);
1704         if (ret) {
1705             return ret;
1706         }
1707     } else {
1708         /* Begin the rebuild, use QEMU emulated list bits */
1709         pdev->config[PCI_CAPABILITY_LIST] = 0;
1710         vdev->emulated_config_bits[PCI_CAPABILITY_LIST] = 0xff;
1711         vdev->emulated_config_bits[PCI_STATUS] |= PCI_STATUS_CAP_LIST;
1712     }
1713 
1714     /* Use emulated next pointer to allow dropping caps */
1715     pci_set_byte(vdev->emulated_config_bits + pos + PCI_CAP_LIST_NEXT, 0xff);
1716 
1717     switch (cap_id) {
1718     case PCI_CAP_ID_MSI:
1719         ret = vfio_msi_setup(vdev, pos);
1720         break;
1721     case PCI_CAP_ID_EXP:
1722         vfio_check_pcie_flr(vdev, pos);
1723         ret = vfio_setup_pcie_cap(vdev, pos, size);
1724         break;
1725     case PCI_CAP_ID_MSIX:
1726         ret = vfio_msix_setup(vdev, pos);
1727         break;
1728     case PCI_CAP_ID_PM:
1729         vfio_check_pm_reset(vdev, pos);
1730         vdev->pm_cap = pos;
1731         ret = pci_add_capability(pdev, cap_id, pos, size);
1732         break;
1733     case PCI_CAP_ID_AF:
1734         vfio_check_af_flr(vdev, pos);
1735         ret = pci_add_capability(pdev, cap_id, pos, size);
1736         break;
1737     default:
1738         ret = pci_add_capability(pdev, cap_id, pos, size);
1739         break;
1740     }
1741 
1742     if (ret < 0) {
1743         error_report("vfio: %s Error adding PCI capability "
1744                      "0x%x[0x%x]@0x%x: %d", vdev->vbasedev.name,
1745                      cap_id, size, pos, ret);
1746         return ret;
1747     }
1748 
1749     return 0;
1750 }
1751 
1752 static int vfio_add_capabilities(VFIOPCIDevice *vdev)
1753 {
1754     PCIDevice *pdev = &vdev->pdev;
1755 
1756     if (!(pdev->config[PCI_STATUS] & PCI_STATUS_CAP_LIST) ||
1757         !pdev->config[PCI_CAPABILITY_LIST]) {
1758         return 0; /* Nothing to add */
1759     }
1760 
1761     return vfio_add_std_cap(vdev, pdev->config[PCI_CAPABILITY_LIST]);
1762 }
1763 
1764 static void vfio_pci_pre_reset(VFIOPCIDevice *vdev)
1765 {
1766     PCIDevice *pdev = &vdev->pdev;
1767     uint16_t cmd;
1768 
1769     vfio_disable_interrupts(vdev);
1770 
1771     /* Make sure the device is in D0 */
1772     if (vdev->pm_cap) {
1773         uint16_t pmcsr;
1774         uint8_t state;
1775 
1776         pmcsr = vfio_pci_read_config(pdev, vdev->pm_cap + PCI_PM_CTRL, 2);
1777         state = pmcsr & PCI_PM_CTRL_STATE_MASK;
1778         if (state) {
1779             pmcsr &= ~PCI_PM_CTRL_STATE_MASK;
1780             vfio_pci_write_config(pdev, vdev->pm_cap + PCI_PM_CTRL, pmcsr, 2);
1781             /* vfio handles the necessary delay here */
1782             pmcsr = vfio_pci_read_config(pdev, vdev->pm_cap + PCI_PM_CTRL, 2);
1783             state = pmcsr & PCI_PM_CTRL_STATE_MASK;
1784             if (state) {
1785                 error_report("vfio: Unable to power on device, stuck in D%d",
1786                              state);
1787             }
1788         }
1789     }
1790 
1791     /*
1792      * Stop any ongoing DMA by disconecting I/O, MMIO, and bus master.
1793      * Also put INTx Disable in known state.
1794      */
1795     cmd = vfio_pci_read_config(pdev, PCI_COMMAND, 2);
1796     cmd &= ~(PCI_COMMAND_IO | PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER |
1797              PCI_COMMAND_INTX_DISABLE);
1798     vfio_pci_write_config(pdev, PCI_COMMAND, cmd, 2);
1799 }
1800 
1801 static void vfio_pci_post_reset(VFIOPCIDevice *vdev)
1802 {
1803     vfio_intx_enable(vdev);
1804 }
1805 
1806 static bool vfio_pci_host_match(PCIHostDeviceAddress *addr, const char *name)
1807 {
1808     char tmp[13];
1809 
1810     sprintf(tmp, "%04x:%02x:%02x.%1x", addr->domain,
1811             addr->bus, addr->slot, addr->function);
1812 
1813     return (strcmp(tmp, name) == 0);
1814 }
1815 
1816 static int vfio_pci_hot_reset(VFIOPCIDevice *vdev, bool single)
1817 {
1818     VFIOGroup *group;
1819     struct vfio_pci_hot_reset_info *info;
1820     struct vfio_pci_dependent_device *devices;
1821     struct vfio_pci_hot_reset *reset;
1822     int32_t *fds;
1823     int ret, i, count;
1824     bool multi = false;
1825 
1826     trace_vfio_pci_hot_reset(vdev->vbasedev.name, single ? "one" : "multi");
1827 
1828     vfio_pci_pre_reset(vdev);
1829     vdev->vbasedev.needs_reset = false;
1830 
1831     info = g_malloc0(sizeof(*info));
1832     info->argsz = sizeof(*info);
1833 
1834     ret = ioctl(vdev->vbasedev.fd, VFIO_DEVICE_GET_PCI_HOT_RESET_INFO, info);
1835     if (ret && errno != ENOSPC) {
1836         ret = -errno;
1837         if (!vdev->has_pm_reset) {
1838             error_report("vfio: Cannot reset device %s, "
1839                          "no available reset mechanism.", vdev->vbasedev.name);
1840         }
1841         goto out_single;
1842     }
1843 
1844     count = info->count;
1845     info = g_realloc(info, sizeof(*info) + (count * sizeof(*devices)));
1846     info->argsz = sizeof(*info) + (count * sizeof(*devices));
1847     devices = &info->devices[0];
1848 
1849     ret = ioctl(vdev->vbasedev.fd, VFIO_DEVICE_GET_PCI_HOT_RESET_INFO, info);
1850     if (ret) {
1851         ret = -errno;
1852         error_report("vfio: hot reset info failed: %m");
1853         goto out_single;
1854     }
1855 
1856     trace_vfio_pci_hot_reset_has_dep_devices(vdev->vbasedev.name);
1857 
1858     /* Verify that we have all the groups required */
1859     for (i = 0; i < info->count; i++) {
1860         PCIHostDeviceAddress host;
1861         VFIOPCIDevice *tmp;
1862         VFIODevice *vbasedev_iter;
1863 
1864         host.domain = devices[i].segment;
1865         host.bus = devices[i].bus;
1866         host.slot = PCI_SLOT(devices[i].devfn);
1867         host.function = PCI_FUNC(devices[i].devfn);
1868 
1869         trace_vfio_pci_hot_reset_dep_devices(host.domain,
1870                 host.bus, host.slot, host.function, devices[i].group_id);
1871 
1872         if (vfio_pci_host_match(&host, vdev->vbasedev.name)) {
1873             continue;
1874         }
1875 
1876         QLIST_FOREACH(group, &vfio_group_list, next) {
1877             if (group->groupid == devices[i].group_id) {
1878                 break;
1879             }
1880         }
1881 
1882         if (!group) {
1883             if (!vdev->has_pm_reset) {
1884                 error_report("vfio: Cannot reset device %s, "
1885                              "depends on group %d which is not owned.",
1886                              vdev->vbasedev.name, devices[i].group_id);
1887             }
1888             ret = -EPERM;
1889             goto out;
1890         }
1891 
1892         /* Prep dependent devices for reset and clear our marker. */
1893         QLIST_FOREACH(vbasedev_iter, &group->device_list, next) {
1894             if (vbasedev_iter->type != VFIO_DEVICE_TYPE_PCI) {
1895                 continue;
1896             }
1897             tmp = container_of(vbasedev_iter, VFIOPCIDevice, vbasedev);
1898             if (vfio_pci_host_match(&host, tmp->vbasedev.name)) {
1899                 if (single) {
1900                     ret = -EINVAL;
1901                     goto out_single;
1902                 }
1903                 vfio_pci_pre_reset(tmp);
1904                 tmp->vbasedev.needs_reset = false;
1905                 multi = true;
1906                 break;
1907             }
1908         }
1909     }
1910 
1911     if (!single && !multi) {
1912         ret = -EINVAL;
1913         goto out_single;
1914     }
1915 
1916     /* Determine how many group fds need to be passed */
1917     count = 0;
1918     QLIST_FOREACH(group, &vfio_group_list, next) {
1919         for (i = 0; i < info->count; i++) {
1920             if (group->groupid == devices[i].group_id) {
1921                 count++;
1922                 break;
1923             }
1924         }
1925     }
1926 
1927     reset = g_malloc0(sizeof(*reset) + (count * sizeof(*fds)));
1928     reset->argsz = sizeof(*reset) + (count * sizeof(*fds));
1929     fds = &reset->group_fds[0];
1930 
1931     /* Fill in group fds */
1932     QLIST_FOREACH(group, &vfio_group_list, next) {
1933         for (i = 0; i < info->count; i++) {
1934             if (group->groupid == devices[i].group_id) {
1935                 fds[reset->count++] = group->fd;
1936                 break;
1937             }
1938         }
1939     }
1940 
1941     /* Bus reset! */
1942     ret = ioctl(vdev->vbasedev.fd, VFIO_DEVICE_PCI_HOT_RESET, reset);
1943     g_free(reset);
1944 
1945     trace_vfio_pci_hot_reset_result(vdev->vbasedev.name,
1946                                     ret ? "%m" : "Success");
1947 
1948 out:
1949     /* Re-enable INTx on affected devices */
1950     for (i = 0; i < info->count; i++) {
1951         PCIHostDeviceAddress host;
1952         VFIOPCIDevice *tmp;
1953         VFIODevice *vbasedev_iter;
1954 
1955         host.domain = devices[i].segment;
1956         host.bus = devices[i].bus;
1957         host.slot = PCI_SLOT(devices[i].devfn);
1958         host.function = PCI_FUNC(devices[i].devfn);
1959 
1960         if (vfio_pci_host_match(&host, vdev->vbasedev.name)) {
1961             continue;
1962         }
1963 
1964         QLIST_FOREACH(group, &vfio_group_list, next) {
1965             if (group->groupid == devices[i].group_id) {
1966                 break;
1967             }
1968         }
1969 
1970         if (!group) {
1971             break;
1972         }
1973 
1974         QLIST_FOREACH(vbasedev_iter, &group->device_list, next) {
1975             if (vbasedev_iter->type != VFIO_DEVICE_TYPE_PCI) {
1976                 continue;
1977             }
1978             tmp = container_of(vbasedev_iter, VFIOPCIDevice, vbasedev);
1979             if (vfio_pci_host_match(&host, tmp->vbasedev.name)) {
1980                 vfio_pci_post_reset(tmp);
1981                 break;
1982             }
1983         }
1984     }
1985 out_single:
1986     vfio_pci_post_reset(vdev);
1987     g_free(info);
1988 
1989     return ret;
1990 }
1991 
1992 /*
1993  * We want to differentiate hot reset of mulitple in-use devices vs hot reset
1994  * of a single in-use device.  VFIO_DEVICE_RESET will already handle the case
1995  * of doing hot resets when there is only a single device per bus.  The in-use
1996  * here refers to how many VFIODevices are affected.  A hot reset that affects
1997  * multiple devices, but only a single in-use device, means that we can call
1998  * it from our bus ->reset() callback since the extent is effectively a single
1999  * device.  This allows us to make use of it in the hotplug path.  When there
2000  * are multiple in-use devices, we can only trigger the hot reset during a
2001  * system reset and thus from our reset handler.  We separate _one vs _multi
2002  * here so that we don't overlap and do a double reset on the system reset
2003  * path where both our reset handler and ->reset() callback are used.  Calling
2004  * _one() will only do a hot reset for the one in-use devices case, calling
2005  * _multi() will do nothing if a _one() would have been sufficient.
2006  */
2007 static int vfio_pci_hot_reset_one(VFIOPCIDevice *vdev)
2008 {
2009     return vfio_pci_hot_reset(vdev, true);
2010 }
2011 
2012 static int vfio_pci_hot_reset_multi(VFIODevice *vbasedev)
2013 {
2014     VFIOPCIDevice *vdev = container_of(vbasedev, VFIOPCIDevice, vbasedev);
2015     return vfio_pci_hot_reset(vdev, false);
2016 }
2017 
2018 static void vfio_pci_compute_needs_reset(VFIODevice *vbasedev)
2019 {
2020     VFIOPCIDevice *vdev = container_of(vbasedev, VFIOPCIDevice, vbasedev);
2021     if (!vbasedev->reset_works || (!vdev->has_flr && vdev->has_pm_reset)) {
2022         vbasedev->needs_reset = true;
2023     }
2024 }
2025 
2026 static VFIODeviceOps vfio_pci_ops = {
2027     .vfio_compute_needs_reset = vfio_pci_compute_needs_reset,
2028     .vfio_hot_reset_multi = vfio_pci_hot_reset_multi,
2029     .vfio_eoi = vfio_intx_eoi,
2030 };
2031 
2032 int vfio_populate_vga(VFIOPCIDevice *vdev)
2033 {
2034     VFIODevice *vbasedev = &vdev->vbasedev;
2035     struct vfio_region_info *reg_info;
2036     int ret;
2037 
2038     ret = vfio_get_region_info(vbasedev, VFIO_PCI_VGA_REGION_INDEX, &reg_info);
2039     if (ret) {
2040         return ret;
2041     }
2042 
2043     if (!(reg_info->flags & VFIO_REGION_INFO_FLAG_READ) ||
2044         !(reg_info->flags & VFIO_REGION_INFO_FLAG_WRITE) ||
2045         reg_info->size < 0xbffff + 1) {
2046         error_report("vfio: Unexpected VGA info, flags 0x%lx, size 0x%lx",
2047                      (unsigned long)reg_info->flags,
2048                      (unsigned long)reg_info->size);
2049         g_free(reg_info);
2050         return -EINVAL;
2051     }
2052 
2053     vdev->vga = g_new0(VFIOVGA, 1);
2054 
2055     vdev->vga->fd_offset = reg_info->offset;
2056     vdev->vga->fd = vdev->vbasedev.fd;
2057 
2058     g_free(reg_info);
2059 
2060     vdev->vga->region[QEMU_PCI_VGA_MEM].offset = QEMU_PCI_VGA_MEM_BASE;
2061     vdev->vga->region[QEMU_PCI_VGA_MEM].nr = QEMU_PCI_VGA_MEM;
2062     QLIST_INIT(&vdev->vga->region[QEMU_PCI_VGA_MEM].quirks);
2063 
2064     memory_region_init_io(&vdev->vga->region[QEMU_PCI_VGA_MEM].mem,
2065                           OBJECT(vdev), &vfio_vga_ops,
2066                           &vdev->vga->region[QEMU_PCI_VGA_MEM],
2067                           "vfio-vga-mmio@0xa0000",
2068                           QEMU_PCI_VGA_MEM_SIZE);
2069 
2070     vdev->vga->region[QEMU_PCI_VGA_IO_LO].offset = QEMU_PCI_VGA_IO_LO_BASE;
2071     vdev->vga->region[QEMU_PCI_VGA_IO_LO].nr = QEMU_PCI_VGA_IO_LO;
2072     QLIST_INIT(&vdev->vga->region[QEMU_PCI_VGA_IO_LO].quirks);
2073 
2074     memory_region_init_io(&vdev->vga->region[QEMU_PCI_VGA_IO_LO].mem,
2075                           OBJECT(vdev), &vfio_vga_ops,
2076                           &vdev->vga->region[QEMU_PCI_VGA_IO_LO],
2077                           "vfio-vga-io@0x3b0",
2078                           QEMU_PCI_VGA_IO_LO_SIZE);
2079 
2080     vdev->vga->region[QEMU_PCI_VGA_IO_HI].offset = QEMU_PCI_VGA_IO_HI_BASE;
2081     vdev->vga->region[QEMU_PCI_VGA_IO_HI].nr = QEMU_PCI_VGA_IO_HI;
2082     QLIST_INIT(&vdev->vga->region[QEMU_PCI_VGA_IO_HI].quirks);
2083 
2084     memory_region_init_io(&vdev->vga->region[QEMU_PCI_VGA_IO_HI].mem,
2085                           OBJECT(vdev), &vfio_vga_ops,
2086                           &vdev->vga->region[QEMU_PCI_VGA_IO_HI],
2087                           "vfio-vga-io@0x3c0",
2088                           QEMU_PCI_VGA_IO_HI_SIZE);
2089 
2090     pci_register_vga(&vdev->pdev, &vdev->vga->region[QEMU_PCI_VGA_MEM].mem,
2091                      &vdev->vga->region[QEMU_PCI_VGA_IO_LO].mem,
2092                      &vdev->vga->region[QEMU_PCI_VGA_IO_HI].mem);
2093 
2094     return 0;
2095 }
2096 
2097 static int vfio_populate_device(VFIOPCIDevice *vdev)
2098 {
2099     VFIODevice *vbasedev = &vdev->vbasedev;
2100     struct vfio_region_info *reg_info;
2101     struct vfio_irq_info irq_info = { .argsz = sizeof(irq_info) };
2102     int i, ret = -1;
2103 
2104     /* Sanity check device */
2105     if (!(vbasedev->flags & VFIO_DEVICE_FLAGS_PCI)) {
2106         error_report("vfio: Um, this isn't a PCI device");
2107         goto error;
2108     }
2109 
2110     if (vbasedev->num_regions < VFIO_PCI_CONFIG_REGION_INDEX + 1) {
2111         error_report("vfio: unexpected number of io regions %u",
2112                      vbasedev->num_regions);
2113         goto error;
2114     }
2115 
2116     if (vbasedev->num_irqs < VFIO_PCI_MSIX_IRQ_INDEX + 1) {
2117         error_report("vfio: unexpected number of irqs %u", vbasedev->num_irqs);
2118         goto error;
2119     }
2120 
2121     for (i = VFIO_PCI_BAR0_REGION_INDEX; i < VFIO_PCI_ROM_REGION_INDEX; i++) {
2122         char *name = g_strdup_printf("%s BAR %d", vbasedev->name, i);
2123 
2124         ret = vfio_region_setup(OBJECT(vdev), vbasedev,
2125                                 &vdev->bars[i].region, i, name);
2126         g_free(name);
2127 
2128         if (ret) {
2129             error_report("vfio: Error getting region %d info: %m", i);
2130             goto error;
2131         }
2132 
2133         QLIST_INIT(&vdev->bars[i].quirks);
2134     }
2135 
2136     ret = vfio_get_region_info(vbasedev,
2137                                VFIO_PCI_CONFIG_REGION_INDEX, &reg_info);
2138     if (ret) {
2139         error_report("vfio: Error getting config info: %m");
2140         goto error;
2141     }
2142 
2143     trace_vfio_populate_device_config(vdev->vbasedev.name,
2144                                       (unsigned long)reg_info->size,
2145                                       (unsigned long)reg_info->offset,
2146                                       (unsigned long)reg_info->flags);
2147 
2148     vdev->config_size = reg_info->size;
2149     if (vdev->config_size == PCI_CONFIG_SPACE_SIZE) {
2150         vdev->pdev.cap_present &= ~QEMU_PCI_CAP_EXPRESS;
2151     }
2152     vdev->config_offset = reg_info->offset;
2153 
2154     g_free(reg_info);
2155 
2156     if (vdev->features & VFIO_FEATURE_ENABLE_VGA) {
2157         ret = vfio_populate_vga(vdev);
2158         if (ret) {
2159             error_report(
2160                 "vfio: Device does not support requested feature x-vga");
2161             goto error;
2162         }
2163     }
2164 
2165     irq_info.index = VFIO_PCI_ERR_IRQ_INDEX;
2166 
2167     ret = ioctl(vdev->vbasedev.fd, VFIO_DEVICE_GET_IRQ_INFO, &irq_info);
2168     if (ret) {
2169         /* This can fail for an old kernel or legacy PCI dev */
2170         trace_vfio_populate_device_get_irq_info_failure();
2171         ret = 0;
2172     } else if (irq_info.count == 1) {
2173         vdev->pci_aer = true;
2174     } else {
2175         error_report("vfio: %s "
2176                      "Could not enable error recovery for the device",
2177                      vbasedev->name);
2178     }
2179 
2180 error:
2181     return ret;
2182 }
2183 
2184 static void vfio_put_device(VFIOPCIDevice *vdev)
2185 {
2186     g_free(vdev->vbasedev.name);
2187     g_free(vdev->msix);
2188 
2189     vfio_put_base_device(&vdev->vbasedev);
2190 }
2191 
2192 static void vfio_err_notifier_handler(void *opaque)
2193 {
2194     VFIOPCIDevice *vdev = opaque;
2195 
2196     if (!event_notifier_test_and_clear(&vdev->err_notifier)) {
2197         return;
2198     }
2199 
2200     /*
2201      * TBD. Retrieve the error details and decide what action
2202      * needs to be taken. One of the actions could be to pass
2203      * the error to the guest and have the guest driver recover
2204      * from the error. This requires that PCIe capabilities be
2205      * exposed to the guest. For now, we just terminate the
2206      * guest to contain the error.
2207      */
2208 
2209     error_report("%s(%s) Unrecoverable error detected. Please collect any data possible and then kill the guest", __func__, vdev->vbasedev.name);
2210 
2211     vm_stop(RUN_STATE_INTERNAL_ERROR);
2212 }
2213 
2214 /*
2215  * Registers error notifier for devices supporting error recovery.
2216  * If we encounter a failure in this function, we report an error
2217  * and continue after disabling error recovery support for the
2218  * device.
2219  */
2220 static void vfio_register_err_notifier(VFIOPCIDevice *vdev)
2221 {
2222     int ret;
2223     int argsz;
2224     struct vfio_irq_set *irq_set;
2225     int32_t *pfd;
2226 
2227     if (!vdev->pci_aer) {
2228         return;
2229     }
2230 
2231     if (event_notifier_init(&vdev->err_notifier, 0)) {
2232         error_report("vfio: Unable to init event notifier for error detection");
2233         vdev->pci_aer = false;
2234         return;
2235     }
2236 
2237     argsz = sizeof(*irq_set) + sizeof(*pfd);
2238 
2239     irq_set = g_malloc0(argsz);
2240     irq_set->argsz = argsz;
2241     irq_set->flags = VFIO_IRQ_SET_DATA_EVENTFD |
2242                      VFIO_IRQ_SET_ACTION_TRIGGER;
2243     irq_set->index = VFIO_PCI_ERR_IRQ_INDEX;
2244     irq_set->start = 0;
2245     irq_set->count = 1;
2246     pfd = (int32_t *)&irq_set->data;
2247 
2248     *pfd = event_notifier_get_fd(&vdev->err_notifier);
2249     qemu_set_fd_handler(*pfd, vfio_err_notifier_handler, NULL, vdev);
2250 
2251     ret = ioctl(vdev->vbasedev.fd, VFIO_DEVICE_SET_IRQS, irq_set);
2252     if (ret) {
2253         error_report("vfio: Failed to set up error notification");
2254         qemu_set_fd_handler(*pfd, NULL, NULL, vdev);
2255         event_notifier_cleanup(&vdev->err_notifier);
2256         vdev->pci_aer = false;
2257     }
2258     g_free(irq_set);
2259 }
2260 
2261 static void vfio_unregister_err_notifier(VFIOPCIDevice *vdev)
2262 {
2263     int argsz;
2264     struct vfio_irq_set *irq_set;
2265     int32_t *pfd;
2266     int ret;
2267 
2268     if (!vdev->pci_aer) {
2269         return;
2270     }
2271 
2272     argsz = sizeof(*irq_set) + sizeof(*pfd);
2273 
2274     irq_set = g_malloc0(argsz);
2275     irq_set->argsz = argsz;
2276     irq_set->flags = VFIO_IRQ_SET_DATA_EVENTFD |
2277                      VFIO_IRQ_SET_ACTION_TRIGGER;
2278     irq_set->index = VFIO_PCI_ERR_IRQ_INDEX;
2279     irq_set->start = 0;
2280     irq_set->count = 1;
2281     pfd = (int32_t *)&irq_set->data;
2282     *pfd = -1;
2283 
2284     ret = ioctl(vdev->vbasedev.fd, VFIO_DEVICE_SET_IRQS, irq_set);
2285     if (ret) {
2286         error_report("vfio: Failed to de-assign error fd: %m");
2287     }
2288     g_free(irq_set);
2289     qemu_set_fd_handler(event_notifier_get_fd(&vdev->err_notifier),
2290                         NULL, NULL, vdev);
2291     event_notifier_cleanup(&vdev->err_notifier);
2292 }
2293 
2294 static void vfio_req_notifier_handler(void *opaque)
2295 {
2296     VFIOPCIDevice *vdev = opaque;
2297 
2298     if (!event_notifier_test_and_clear(&vdev->req_notifier)) {
2299         return;
2300     }
2301 
2302     qdev_unplug(&vdev->pdev.qdev, NULL);
2303 }
2304 
2305 static void vfio_register_req_notifier(VFIOPCIDevice *vdev)
2306 {
2307     struct vfio_irq_info irq_info = { .argsz = sizeof(irq_info),
2308                                       .index = VFIO_PCI_REQ_IRQ_INDEX };
2309     int argsz;
2310     struct vfio_irq_set *irq_set;
2311     int32_t *pfd;
2312 
2313     if (!(vdev->features & VFIO_FEATURE_ENABLE_REQ)) {
2314         return;
2315     }
2316 
2317     if (ioctl(vdev->vbasedev.fd,
2318               VFIO_DEVICE_GET_IRQ_INFO, &irq_info) < 0 || irq_info.count < 1) {
2319         return;
2320     }
2321 
2322     if (event_notifier_init(&vdev->req_notifier, 0)) {
2323         error_report("vfio: Unable to init event notifier for device request");
2324         return;
2325     }
2326 
2327     argsz = sizeof(*irq_set) + sizeof(*pfd);
2328 
2329     irq_set = g_malloc0(argsz);
2330     irq_set->argsz = argsz;
2331     irq_set->flags = VFIO_IRQ_SET_DATA_EVENTFD |
2332                      VFIO_IRQ_SET_ACTION_TRIGGER;
2333     irq_set->index = VFIO_PCI_REQ_IRQ_INDEX;
2334     irq_set->start = 0;
2335     irq_set->count = 1;
2336     pfd = (int32_t *)&irq_set->data;
2337 
2338     *pfd = event_notifier_get_fd(&vdev->req_notifier);
2339     qemu_set_fd_handler(*pfd, vfio_req_notifier_handler, NULL, vdev);
2340 
2341     if (ioctl(vdev->vbasedev.fd, VFIO_DEVICE_SET_IRQS, irq_set)) {
2342         error_report("vfio: Failed to set up device request notification");
2343         qemu_set_fd_handler(*pfd, NULL, NULL, vdev);
2344         event_notifier_cleanup(&vdev->req_notifier);
2345     } else {
2346         vdev->req_enabled = true;
2347     }
2348 
2349     g_free(irq_set);
2350 }
2351 
2352 static void vfio_unregister_req_notifier(VFIOPCIDevice *vdev)
2353 {
2354     int argsz;
2355     struct vfio_irq_set *irq_set;
2356     int32_t *pfd;
2357 
2358     if (!vdev->req_enabled) {
2359         return;
2360     }
2361 
2362     argsz = sizeof(*irq_set) + sizeof(*pfd);
2363 
2364     irq_set = g_malloc0(argsz);
2365     irq_set->argsz = argsz;
2366     irq_set->flags = VFIO_IRQ_SET_DATA_EVENTFD |
2367                      VFIO_IRQ_SET_ACTION_TRIGGER;
2368     irq_set->index = VFIO_PCI_REQ_IRQ_INDEX;
2369     irq_set->start = 0;
2370     irq_set->count = 1;
2371     pfd = (int32_t *)&irq_set->data;
2372     *pfd = -1;
2373 
2374     if (ioctl(vdev->vbasedev.fd, VFIO_DEVICE_SET_IRQS, irq_set)) {
2375         error_report("vfio: Failed to de-assign device request fd: %m");
2376     }
2377     g_free(irq_set);
2378     qemu_set_fd_handler(event_notifier_get_fd(&vdev->req_notifier),
2379                         NULL, NULL, vdev);
2380     event_notifier_cleanup(&vdev->req_notifier);
2381 
2382     vdev->req_enabled = false;
2383 }
2384 
2385 static int vfio_initfn(PCIDevice *pdev)
2386 {
2387     VFIOPCIDevice *vdev = DO_UPCAST(VFIOPCIDevice, pdev, pdev);
2388     VFIODevice *vbasedev_iter;
2389     VFIOGroup *group;
2390     char *tmp, group_path[PATH_MAX], *group_name;
2391     ssize_t len;
2392     struct stat st;
2393     int groupid;
2394     int i, ret;
2395 
2396     if (!vdev->vbasedev.sysfsdev) {
2397         vdev->vbasedev.sysfsdev =
2398             g_strdup_printf("/sys/bus/pci/devices/%04x:%02x:%02x.%01x",
2399                             vdev->host.domain, vdev->host.bus,
2400                             vdev->host.slot, vdev->host.function);
2401     }
2402 
2403     if (stat(vdev->vbasedev.sysfsdev, &st) < 0) {
2404         error_report("vfio: error: no such host device: %s",
2405                      vdev->vbasedev.sysfsdev);
2406         return -errno;
2407     }
2408 
2409     vdev->vbasedev.name = g_strdup(basename(vdev->vbasedev.sysfsdev));
2410     vdev->vbasedev.ops = &vfio_pci_ops;
2411     vdev->vbasedev.type = VFIO_DEVICE_TYPE_PCI;
2412 
2413     tmp = g_strdup_printf("%s/iommu_group", vdev->vbasedev.sysfsdev);
2414     len = readlink(tmp, group_path, sizeof(group_path));
2415     g_free(tmp);
2416 
2417     if (len <= 0 || len >= sizeof(group_path)) {
2418         error_report("vfio: error no iommu_group for device");
2419         return len < 0 ? -errno : -ENAMETOOLONG;
2420     }
2421 
2422     group_path[len] = 0;
2423 
2424     group_name = basename(group_path);
2425     if (sscanf(group_name, "%d", &groupid) != 1) {
2426         error_report("vfio: error reading %s: %m", group_path);
2427         return -errno;
2428     }
2429 
2430     trace_vfio_initfn(vdev->vbasedev.name, groupid);
2431 
2432     group = vfio_get_group(groupid, pci_device_iommu_address_space(pdev));
2433     if (!group) {
2434         error_report("vfio: failed to get group %d", groupid);
2435         return -ENOENT;
2436     }
2437 
2438     QLIST_FOREACH(vbasedev_iter, &group->device_list, next) {
2439         if (strcmp(vbasedev_iter->name, vdev->vbasedev.name) == 0) {
2440             error_report("vfio: error: device %s is already attached",
2441                          vdev->vbasedev.name);
2442             vfio_put_group(group);
2443             return -EBUSY;
2444         }
2445     }
2446 
2447     ret = vfio_get_device(group, vdev->vbasedev.name, &vdev->vbasedev);
2448     if (ret) {
2449         error_report("vfio: failed to get device %s", vdev->vbasedev.name);
2450         vfio_put_group(group);
2451         return ret;
2452     }
2453 
2454     ret = vfio_populate_device(vdev);
2455     if (ret) {
2456         return ret;
2457     }
2458 
2459     /* Get a copy of config space */
2460     ret = pread(vdev->vbasedev.fd, vdev->pdev.config,
2461                 MIN(pci_config_size(&vdev->pdev), vdev->config_size),
2462                 vdev->config_offset);
2463     if (ret < (int)MIN(pci_config_size(&vdev->pdev), vdev->config_size)) {
2464         ret = ret < 0 ? -errno : -EFAULT;
2465         error_report("vfio: Failed to read device config space");
2466         return ret;
2467     }
2468 
2469     /* vfio emulates a lot for us, but some bits need extra love */
2470     vdev->emulated_config_bits = g_malloc0(vdev->config_size);
2471 
2472     /* QEMU can choose to expose the ROM or not */
2473     memset(vdev->emulated_config_bits + PCI_ROM_ADDRESS, 0xff, 4);
2474 
2475     /*
2476      * The PCI spec reserves vendor ID 0xffff as an invalid value.  The
2477      * device ID is managed by the vendor and need only be a 16-bit value.
2478      * Allow any 16-bit value for subsystem so they can be hidden or changed.
2479      */
2480     if (vdev->vendor_id != PCI_ANY_ID) {
2481         if (vdev->vendor_id >= 0xffff) {
2482             error_report("vfio: Invalid PCI vendor ID provided");
2483             return -EINVAL;
2484         }
2485         vfio_add_emulated_word(vdev, PCI_VENDOR_ID, vdev->vendor_id, ~0);
2486         trace_vfio_pci_emulated_vendor_id(vdev->vbasedev.name, vdev->vendor_id);
2487     } else {
2488         vdev->vendor_id = pci_get_word(pdev->config + PCI_VENDOR_ID);
2489     }
2490 
2491     if (vdev->device_id != PCI_ANY_ID) {
2492         if (vdev->device_id > 0xffff) {
2493             error_report("vfio: Invalid PCI device ID provided");
2494             return -EINVAL;
2495         }
2496         vfio_add_emulated_word(vdev, PCI_DEVICE_ID, vdev->device_id, ~0);
2497         trace_vfio_pci_emulated_device_id(vdev->vbasedev.name, vdev->device_id);
2498     } else {
2499         vdev->device_id = pci_get_word(pdev->config + PCI_DEVICE_ID);
2500     }
2501 
2502     if (vdev->sub_vendor_id != PCI_ANY_ID) {
2503         if (vdev->sub_vendor_id > 0xffff) {
2504             error_report("vfio: Invalid PCI subsystem vendor ID provided");
2505             return -EINVAL;
2506         }
2507         vfio_add_emulated_word(vdev, PCI_SUBSYSTEM_VENDOR_ID,
2508                                vdev->sub_vendor_id, ~0);
2509         trace_vfio_pci_emulated_sub_vendor_id(vdev->vbasedev.name,
2510                                               vdev->sub_vendor_id);
2511     }
2512 
2513     if (vdev->sub_device_id != PCI_ANY_ID) {
2514         if (vdev->sub_device_id > 0xffff) {
2515             error_report("vfio: Invalid PCI subsystem device ID provided");
2516             return -EINVAL;
2517         }
2518         vfio_add_emulated_word(vdev, PCI_SUBSYSTEM_ID, vdev->sub_device_id, ~0);
2519         trace_vfio_pci_emulated_sub_device_id(vdev->vbasedev.name,
2520                                               vdev->sub_device_id);
2521     }
2522 
2523     /* QEMU can change multi-function devices to single function, or reverse */
2524     vdev->emulated_config_bits[PCI_HEADER_TYPE] =
2525                                               PCI_HEADER_TYPE_MULTI_FUNCTION;
2526 
2527     /* Restore or clear multifunction, this is always controlled by QEMU */
2528     if (vdev->pdev.cap_present & QEMU_PCI_CAP_MULTIFUNCTION) {
2529         vdev->pdev.config[PCI_HEADER_TYPE] |= PCI_HEADER_TYPE_MULTI_FUNCTION;
2530     } else {
2531         vdev->pdev.config[PCI_HEADER_TYPE] &= ~PCI_HEADER_TYPE_MULTI_FUNCTION;
2532     }
2533 
2534     /*
2535      * Clear host resource mapping info.  If we choose not to register a
2536      * BAR, such as might be the case with the option ROM, we can get
2537      * confusing, unwritable, residual addresses from the host here.
2538      */
2539     memset(&vdev->pdev.config[PCI_BASE_ADDRESS_0], 0, 24);
2540     memset(&vdev->pdev.config[PCI_ROM_ADDRESS], 0, 4);
2541 
2542     vfio_pci_size_rom(vdev);
2543 
2544     ret = vfio_msix_early_setup(vdev);
2545     if (ret) {
2546         return ret;
2547     }
2548 
2549     vfio_bars_setup(vdev);
2550 
2551     ret = vfio_add_capabilities(vdev);
2552     if (ret) {
2553         goto out_teardown;
2554     }
2555 
2556     if (vdev->vga) {
2557         vfio_vga_quirk_setup(vdev);
2558     }
2559 
2560     for (i = 0; i < PCI_ROM_SLOT; i++) {
2561         vfio_bar_quirk_setup(vdev, i);
2562     }
2563 
2564     if (!vdev->igd_opregion &&
2565         vdev->features & VFIO_FEATURE_ENABLE_IGD_OPREGION) {
2566         struct vfio_region_info *opregion;
2567 
2568         if (vdev->pdev.qdev.hotplugged) {
2569             error_report("Cannot support IGD OpRegion feature on hotplugged "
2570                          "device %s", vdev->vbasedev.name);
2571             ret = -EINVAL;
2572             goto out_teardown;
2573         }
2574 
2575         ret = vfio_get_dev_region_info(&vdev->vbasedev,
2576                         VFIO_REGION_TYPE_PCI_VENDOR_TYPE | PCI_VENDOR_ID_INTEL,
2577                         VFIO_REGION_SUBTYPE_INTEL_IGD_OPREGION, &opregion);
2578         if (ret) {
2579             error_report("Device %s does not support requested IGD OpRegion "
2580                          "feature", vdev->vbasedev.name);
2581             goto out_teardown;
2582         }
2583 
2584         ret = vfio_pci_igd_opregion_init(vdev, opregion);
2585         g_free(opregion);
2586         if (ret) {
2587             error_report("Device %s IGD OpRegion initialization failed",
2588                          vdev->vbasedev.name);
2589             goto out_teardown;
2590         }
2591     }
2592 
2593     /* QEMU emulates all of MSI & MSIX */
2594     if (pdev->cap_present & QEMU_PCI_CAP_MSIX) {
2595         memset(vdev->emulated_config_bits + pdev->msix_cap, 0xff,
2596                MSIX_CAP_LENGTH);
2597     }
2598 
2599     if (pdev->cap_present & QEMU_PCI_CAP_MSI) {
2600         memset(vdev->emulated_config_bits + pdev->msi_cap, 0xff,
2601                vdev->msi_cap_size);
2602     }
2603 
2604     if (vfio_pci_read_config(&vdev->pdev, PCI_INTERRUPT_PIN, 1)) {
2605         vdev->intx.mmap_timer = timer_new_ms(QEMU_CLOCK_VIRTUAL,
2606                                                   vfio_intx_mmap_enable, vdev);
2607         pci_device_set_intx_routing_notifier(&vdev->pdev, vfio_intx_update);
2608         ret = vfio_intx_enable(vdev);
2609         if (ret) {
2610             goto out_teardown;
2611         }
2612     }
2613 
2614     vfio_register_err_notifier(vdev);
2615     vfio_register_req_notifier(vdev);
2616     vfio_setup_resetfn_quirk(vdev);
2617 
2618     return 0;
2619 
2620 out_teardown:
2621     pci_device_set_intx_routing_notifier(&vdev->pdev, NULL);
2622     vfio_teardown_msi(vdev);
2623     vfio_bars_exit(vdev);
2624     return ret;
2625 }
2626 
2627 static void vfio_instance_finalize(Object *obj)
2628 {
2629     PCIDevice *pci_dev = PCI_DEVICE(obj);
2630     VFIOPCIDevice *vdev = DO_UPCAST(VFIOPCIDevice, pdev, pci_dev);
2631     VFIOGroup *group = vdev->vbasedev.group;
2632 
2633     vfio_bars_finalize(vdev);
2634     g_free(vdev->emulated_config_bits);
2635     g_free(vdev->rom);
2636     /*
2637      * XXX Leaking igd_opregion is not an oversight, we can't remove the
2638      * fw_cfg entry therefore leaking this allocation seems like the safest
2639      * option.
2640      *
2641      * g_free(vdev->igd_opregion);
2642      */
2643     vfio_put_device(vdev);
2644     vfio_put_group(group);
2645 }
2646 
2647 static void vfio_exitfn(PCIDevice *pdev)
2648 {
2649     VFIOPCIDevice *vdev = DO_UPCAST(VFIOPCIDevice, pdev, pdev);
2650 
2651     vfio_unregister_req_notifier(vdev);
2652     vfio_unregister_err_notifier(vdev);
2653     pci_device_set_intx_routing_notifier(&vdev->pdev, NULL);
2654     vfio_disable_interrupts(vdev);
2655     if (vdev->intx.mmap_timer) {
2656         timer_free(vdev->intx.mmap_timer);
2657     }
2658     vfio_teardown_msi(vdev);
2659     vfio_bars_exit(vdev);
2660 }
2661 
2662 static void vfio_pci_reset(DeviceState *dev)
2663 {
2664     PCIDevice *pdev = DO_UPCAST(PCIDevice, qdev, dev);
2665     VFIOPCIDevice *vdev = DO_UPCAST(VFIOPCIDevice, pdev, pdev);
2666 
2667     trace_vfio_pci_reset(vdev->vbasedev.name);
2668 
2669     vfio_pci_pre_reset(vdev);
2670 
2671     if (vdev->resetfn && !vdev->resetfn(vdev)) {
2672         goto post_reset;
2673     }
2674 
2675     if (vdev->vbasedev.reset_works &&
2676         (vdev->has_flr || !vdev->has_pm_reset) &&
2677         !ioctl(vdev->vbasedev.fd, VFIO_DEVICE_RESET)) {
2678         trace_vfio_pci_reset_flr(vdev->vbasedev.name);
2679         goto post_reset;
2680     }
2681 
2682     /* See if we can do our own bus reset */
2683     if (!vfio_pci_hot_reset_one(vdev)) {
2684         goto post_reset;
2685     }
2686 
2687     /* If nothing else works and the device supports PM reset, use it */
2688     if (vdev->vbasedev.reset_works && vdev->has_pm_reset &&
2689         !ioctl(vdev->vbasedev.fd, VFIO_DEVICE_RESET)) {
2690         trace_vfio_pci_reset_pm(vdev->vbasedev.name);
2691         goto post_reset;
2692     }
2693 
2694 post_reset:
2695     vfio_pci_post_reset(vdev);
2696 }
2697 
2698 static void vfio_instance_init(Object *obj)
2699 {
2700     PCIDevice *pci_dev = PCI_DEVICE(obj);
2701     VFIOPCIDevice *vdev = DO_UPCAST(VFIOPCIDevice, pdev, PCI_DEVICE(obj));
2702 
2703     device_add_bootindex_property(obj, &vdev->bootindex,
2704                                   "bootindex", NULL,
2705                                   &pci_dev->qdev, NULL);
2706 }
2707 
2708 static Property vfio_pci_dev_properties[] = {
2709     DEFINE_PROP_PCI_HOST_DEVADDR("host", VFIOPCIDevice, host),
2710     DEFINE_PROP_STRING("sysfsdev", VFIOPCIDevice, vbasedev.sysfsdev),
2711     DEFINE_PROP_UINT32("x-intx-mmap-timeout-ms", VFIOPCIDevice,
2712                        intx.mmap_timeout, 1100),
2713     DEFINE_PROP_BIT("x-vga", VFIOPCIDevice, features,
2714                     VFIO_FEATURE_ENABLE_VGA_BIT, false),
2715     DEFINE_PROP_BIT("x-req", VFIOPCIDevice, features,
2716                     VFIO_FEATURE_ENABLE_REQ_BIT, true),
2717     DEFINE_PROP_BIT("x-igd-opregion", VFIOPCIDevice, features,
2718                     VFIO_FEATURE_ENABLE_IGD_OPREGION_BIT, false),
2719     DEFINE_PROP_BOOL("x-no-mmap", VFIOPCIDevice, vbasedev.no_mmap, false),
2720     DEFINE_PROP_BOOL("x-no-kvm-intx", VFIOPCIDevice, no_kvm_intx, false),
2721     DEFINE_PROP_BOOL("x-no-kvm-msi", VFIOPCIDevice, no_kvm_msi, false),
2722     DEFINE_PROP_BOOL("x-no-kvm-msix", VFIOPCIDevice, no_kvm_msix, false),
2723     DEFINE_PROP_UINT32("x-pci-vendor-id", VFIOPCIDevice, vendor_id, PCI_ANY_ID),
2724     DEFINE_PROP_UINT32("x-pci-device-id", VFIOPCIDevice, device_id, PCI_ANY_ID),
2725     DEFINE_PROP_UINT32("x-pci-sub-vendor-id", VFIOPCIDevice,
2726                        sub_vendor_id, PCI_ANY_ID),
2727     DEFINE_PROP_UINT32("x-pci-sub-device-id", VFIOPCIDevice,
2728                        sub_device_id, PCI_ANY_ID),
2729     DEFINE_PROP_UINT32("x-igd-gms", VFIOPCIDevice, igd_gms, 0),
2730     /*
2731      * TODO - support passed fds... is this necessary?
2732      * DEFINE_PROP_STRING("vfiofd", VFIOPCIDevice, vfiofd_name),
2733      * DEFINE_PROP_STRING("vfiogroupfd, VFIOPCIDevice, vfiogroupfd_name),
2734      */
2735     DEFINE_PROP_END_OF_LIST(),
2736 };
2737 
2738 static const VMStateDescription vfio_pci_vmstate = {
2739     .name = "vfio-pci",
2740     .unmigratable = 1,
2741 };
2742 
2743 static void vfio_pci_dev_class_init(ObjectClass *klass, void *data)
2744 {
2745     DeviceClass *dc = DEVICE_CLASS(klass);
2746     PCIDeviceClass *pdc = PCI_DEVICE_CLASS(klass);
2747 
2748     dc->reset = vfio_pci_reset;
2749     dc->props = vfio_pci_dev_properties;
2750     dc->vmsd = &vfio_pci_vmstate;
2751     dc->desc = "VFIO-based PCI device assignment";
2752     set_bit(DEVICE_CATEGORY_MISC, dc->categories);
2753     pdc->init = vfio_initfn;
2754     pdc->exit = vfio_exitfn;
2755     pdc->config_read = vfio_pci_read_config;
2756     pdc->config_write = vfio_pci_write_config;
2757     pdc->is_express = 1; /* We might be */
2758 }
2759 
2760 static const TypeInfo vfio_pci_dev_info = {
2761     .name = "vfio-pci",
2762     .parent = TYPE_PCI_DEVICE,
2763     .instance_size = sizeof(VFIOPCIDevice),
2764     .class_init = vfio_pci_dev_class_init,
2765     .instance_init = vfio_instance_init,
2766     .instance_finalize = vfio_instance_finalize,
2767 };
2768 
2769 static void register_vfio_pci_dev_type(void)
2770 {
2771     type_register_static(&vfio_pci_dev_info);
2772 }
2773 
2774 type_init(register_vfio_pci_dev_type)
2775