xref: /qemu/hw/vfio/iommufd.c (revision c07cd110a1824e2d046581af7375f16dac26e96f)
1 /*
2  * iommufd container backend
3  *
4  * Copyright (C) 2023 Intel Corporation.
5  * Copyright Red Hat, Inc. 2023
6  *
7  * Authors: Yi Liu <yi.l.liu@intel.com>
8  *          Eric Auger <eric.auger@redhat.com>
9  *
10  * SPDX-License-Identifier: GPL-2.0-or-later
11  */
12 
13 #include "qemu/osdep.h"
14 #include <sys/ioctl.h>
15 #include <linux/vfio.h>
16 #include <linux/iommufd.h>
17 
18 #include "hw/vfio/vfio-common.h"
19 #include "qemu/error-report.h"
20 #include "trace.h"
21 #include "qapi/error.h"
22 #include "system/iommufd.h"
23 #include "hw/qdev-core.h"
24 #include "system/reset.h"
25 #include "qemu/cutils.h"
26 #include "qemu/chardev_open.h"
27 #include "pci.h"
28 
29 static int iommufd_cdev_map(const VFIOContainerBase *bcontainer, hwaddr iova,
30                             ram_addr_t size, void *vaddr, bool readonly)
31 {
32     const VFIOIOMMUFDContainer *container =
33         container_of(bcontainer, VFIOIOMMUFDContainer, bcontainer);
34 
35     return iommufd_backend_map_dma(container->be,
36                                    container->ioas_id,
37                                    iova, size, vaddr, readonly);
38 }
39 
40 static int iommufd_cdev_unmap(const VFIOContainerBase *bcontainer,
41                               hwaddr iova, ram_addr_t size,
42                               IOMMUTLBEntry *iotlb)
43 {
44     const VFIOIOMMUFDContainer *container =
45         container_of(bcontainer, VFIOIOMMUFDContainer, bcontainer);
46 
47     /* TODO: Handle dma_unmap_bitmap with iotlb args (migration) */
48     return iommufd_backend_unmap_dma(container->be,
49                                      container->ioas_id, iova, size);
50 }
51 
52 static bool iommufd_cdev_kvm_device_add(VFIODevice *vbasedev, Error **errp)
53 {
54     return !vfio_kvm_device_add_fd(vbasedev->fd, errp);
55 }
56 
57 static void iommufd_cdev_kvm_device_del(VFIODevice *vbasedev)
58 {
59     Error *err = NULL;
60 
61     if (vfio_kvm_device_del_fd(vbasedev->fd, &err)) {
62         error_report_err(err);
63     }
64 }
65 
66 static bool iommufd_cdev_connect_and_bind(VFIODevice *vbasedev, Error **errp)
67 {
68     IOMMUFDBackend *iommufd = vbasedev->iommufd;
69     struct vfio_device_bind_iommufd bind = {
70         .argsz = sizeof(bind),
71         .flags = 0,
72     };
73 
74     if (!iommufd_backend_connect(iommufd, errp)) {
75         return false;
76     }
77 
78     /*
79      * Add device to kvm-vfio to be prepared for the tracking
80      * in KVM. Especially for some emulated devices, it requires
81      * to have kvm information in the device open.
82      */
83     if (!iommufd_cdev_kvm_device_add(vbasedev, errp)) {
84         goto err_kvm_device_add;
85     }
86 
87     /* Bind device to iommufd */
88     bind.iommufd = iommufd->fd;
89     if (ioctl(vbasedev->fd, VFIO_DEVICE_BIND_IOMMUFD, &bind)) {
90         error_setg_errno(errp, errno, "error bind device fd=%d to iommufd=%d",
91                          vbasedev->fd, bind.iommufd);
92         goto err_bind;
93     }
94 
95     vbasedev->devid = bind.out_devid;
96     trace_iommufd_cdev_connect_and_bind(bind.iommufd, vbasedev->name,
97                                         vbasedev->fd, vbasedev->devid);
98     return true;
99 err_bind:
100     iommufd_cdev_kvm_device_del(vbasedev);
101 err_kvm_device_add:
102     iommufd_backend_disconnect(iommufd);
103     return false;
104 }
105 
106 static void iommufd_cdev_unbind_and_disconnect(VFIODevice *vbasedev)
107 {
108     /* Unbind is automatically conducted when device fd is closed */
109     iommufd_cdev_kvm_device_del(vbasedev);
110     iommufd_backend_disconnect(vbasedev->iommufd);
111 }
112 
113 static bool iommufd_hwpt_dirty_tracking(VFIOIOASHwpt *hwpt)
114 {
115     return hwpt && hwpt->hwpt_flags & IOMMU_HWPT_ALLOC_DIRTY_TRACKING;
116 }
117 
118 static int iommufd_set_dirty_page_tracking(const VFIOContainerBase *bcontainer,
119                                            bool start, Error **errp)
120 {
121     const VFIOIOMMUFDContainer *container =
122         container_of(bcontainer, VFIOIOMMUFDContainer, bcontainer);
123     VFIOIOASHwpt *hwpt;
124 
125     QLIST_FOREACH(hwpt, &container->hwpt_list, next) {
126         if (!iommufd_hwpt_dirty_tracking(hwpt)) {
127             continue;
128         }
129 
130         if (!iommufd_backend_set_dirty_tracking(container->be,
131                                                 hwpt->hwpt_id, start, errp)) {
132             goto err;
133         }
134     }
135 
136     return 0;
137 
138 err:
139     QLIST_FOREACH(hwpt, &container->hwpt_list, next) {
140         if (!iommufd_hwpt_dirty_tracking(hwpt)) {
141             continue;
142         }
143         iommufd_backend_set_dirty_tracking(container->be,
144                                            hwpt->hwpt_id, !start, NULL);
145     }
146     return -EINVAL;
147 }
148 
149 static int iommufd_query_dirty_bitmap(const VFIOContainerBase *bcontainer,
150                                       VFIOBitmap *vbmap, hwaddr iova,
151                                       hwaddr size, Error **errp)
152 {
153     VFIOIOMMUFDContainer *container = container_of(bcontainer,
154                                                    VFIOIOMMUFDContainer,
155                                                    bcontainer);
156     unsigned long page_size = qemu_real_host_page_size();
157     VFIOIOASHwpt *hwpt;
158 
159     QLIST_FOREACH(hwpt, &container->hwpt_list, next) {
160         if (!iommufd_hwpt_dirty_tracking(hwpt)) {
161             continue;
162         }
163 
164         if (!iommufd_backend_get_dirty_bitmap(container->be, hwpt->hwpt_id,
165                                               iova, size, page_size,
166                                               (uint64_t *)vbmap->bitmap,
167                                               errp)) {
168             return -EINVAL;
169         }
170     }
171 
172     return 0;
173 }
174 
175 static int iommufd_cdev_getfd(const char *sysfs_path, Error **errp)
176 {
177     ERRP_GUARD();
178     long int ret = -ENOTTY;
179     g_autofree char *path = NULL;
180     g_autofree char *vfio_dev_path = NULL;
181     g_autofree char *vfio_path = NULL;
182     DIR *dir = NULL;
183     struct dirent *dent;
184     g_autofree gchar *contents = NULL;
185     gsize length;
186     int major, minor;
187     dev_t vfio_devt;
188 
189     path = g_strdup_printf("%s/vfio-dev", sysfs_path);
190     dir = opendir(path);
191     if (!dir) {
192         error_setg_errno(errp, errno, "couldn't open directory %s", path);
193         goto out;
194     }
195 
196     while ((dent = readdir(dir))) {
197         if (!strncmp(dent->d_name, "vfio", 4)) {
198             vfio_dev_path = g_strdup_printf("%s/%s/dev", path, dent->d_name);
199             break;
200         }
201     }
202 
203     if (!vfio_dev_path) {
204         error_setg(errp, "failed to find vfio-dev/vfioX/dev");
205         goto out_close_dir;
206     }
207 
208     if (!g_file_get_contents(vfio_dev_path, &contents, &length, NULL)) {
209         error_setg(errp, "failed to load \"%s\"", vfio_dev_path);
210         goto out_close_dir;
211     }
212 
213     if (sscanf(contents, "%d:%d", &major, &minor) != 2) {
214         error_setg(errp, "failed to get major:minor for \"%s\"", vfio_dev_path);
215         goto out_close_dir;
216     }
217     vfio_devt = makedev(major, minor);
218 
219     vfio_path = g_strdup_printf("/dev/vfio/devices/%s", dent->d_name);
220     ret = open_cdev(vfio_path, vfio_devt);
221     if (ret < 0) {
222         error_setg(errp, "Failed to open %s", vfio_path);
223     }
224 
225     trace_iommufd_cdev_getfd(vfio_path, ret);
226 
227 out_close_dir:
228     closedir(dir);
229 out:
230     if (*errp) {
231         error_prepend(errp, VFIO_MSG_PREFIX, path);
232     }
233 
234     return ret;
235 }
236 
237 static int iommufd_cdev_attach_ioas_hwpt(VFIODevice *vbasedev, uint32_t id,
238                                          Error **errp)
239 {
240     int iommufd = vbasedev->iommufd->fd;
241     struct vfio_device_attach_iommufd_pt attach_data = {
242         .argsz = sizeof(attach_data),
243         .flags = 0,
244         .pt_id = id,
245     };
246 
247     /* Attach device to an IOAS or hwpt within iommufd */
248     if (ioctl(vbasedev->fd, VFIO_DEVICE_ATTACH_IOMMUFD_PT, &attach_data)) {
249         error_setg_errno(errp, errno,
250                          "[iommufd=%d] error attach %s (%d) to id=%d",
251                          iommufd, vbasedev->name, vbasedev->fd, id);
252         return -errno;
253     }
254 
255     trace_iommufd_cdev_attach_ioas_hwpt(iommufd, vbasedev->name,
256                                         vbasedev->fd, id);
257     return 0;
258 }
259 
260 static bool iommufd_cdev_detach_ioas_hwpt(VFIODevice *vbasedev, Error **errp)
261 {
262     int iommufd = vbasedev->iommufd->fd;
263     struct vfio_device_detach_iommufd_pt detach_data = {
264         .argsz = sizeof(detach_data),
265         .flags = 0,
266     };
267 
268     if (ioctl(vbasedev->fd, VFIO_DEVICE_DETACH_IOMMUFD_PT, &detach_data)) {
269         error_setg_errno(errp, errno, "detach %s failed", vbasedev->name);
270         return false;
271     }
272 
273     trace_iommufd_cdev_detach_ioas_hwpt(iommufd, vbasedev->name);
274     return true;
275 }
276 
277 static bool iommufd_cdev_autodomains_get(VFIODevice *vbasedev,
278                                          VFIOIOMMUFDContainer *container,
279                                          Error **errp)
280 {
281     ERRP_GUARD();
282     IOMMUFDBackend *iommufd = vbasedev->iommufd;
283     uint32_t flags = 0;
284     VFIOIOASHwpt *hwpt;
285     uint32_t hwpt_id;
286     int ret;
287 
288     /* Try to find a domain */
289     QLIST_FOREACH(hwpt, &container->hwpt_list, next) {
290         ret = iommufd_cdev_attach_ioas_hwpt(vbasedev, hwpt->hwpt_id, errp);
291         if (ret) {
292             /* -EINVAL means the domain is incompatible with the device. */
293             if (ret == -EINVAL) {
294                 /*
295                  * It is an expected failure and it just means we will try
296                  * another domain, or create one if no existing compatible
297                  * domain is found. Hence why the error is discarded below.
298                  */
299                 error_free(*errp);
300                 *errp = NULL;
301                 continue;
302             }
303 
304             return false;
305         } else {
306             vbasedev->hwpt = hwpt;
307             QLIST_INSERT_HEAD(&hwpt->device_list, vbasedev, hwpt_next);
308             vbasedev->iommu_dirty_tracking = iommufd_hwpt_dirty_tracking(hwpt);
309             return true;
310         }
311     }
312 
313     /*
314      * This is quite early and VFIO Migration state isn't yet fully
315      * initialized, thus rely only on IOMMU hardware capabilities as to
316      * whether IOMMU dirty tracking is going to be requested. Later
317      * vfio_migration_realize() may decide to use VF dirty tracking
318      * instead.
319      */
320     if (vbasedev->hiod->caps.hw_caps & IOMMU_HW_CAP_DIRTY_TRACKING) {
321         flags = IOMMU_HWPT_ALLOC_DIRTY_TRACKING;
322     }
323 
324     if (!iommufd_backend_alloc_hwpt(iommufd, vbasedev->devid,
325                                     container->ioas_id, flags,
326                                     IOMMU_HWPT_DATA_NONE, 0, NULL,
327                                     &hwpt_id, errp)) {
328         return false;
329     }
330 
331     hwpt = g_malloc0(sizeof(*hwpt));
332     hwpt->hwpt_id = hwpt_id;
333     hwpt->hwpt_flags = flags;
334     QLIST_INIT(&hwpt->device_list);
335 
336     ret = iommufd_cdev_attach_ioas_hwpt(vbasedev, hwpt->hwpt_id, errp);
337     if (ret) {
338         iommufd_backend_free_id(container->be, hwpt->hwpt_id);
339         g_free(hwpt);
340         return false;
341     }
342 
343     vbasedev->hwpt = hwpt;
344     vbasedev->iommu_dirty_tracking = iommufd_hwpt_dirty_tracking(hwpt);
345     QLIST_INSERT_HEAD(&hwpt->device_list, vbasedev, hwpt_next);
346     QLIST_INSERT_HEAD(&container->hwpt_list, hwpt, next);
347     container->bcontainer.dirty_pages_supported |=
348                                 vbasedev->iommu_dirty_tracking;
349     if (container->bcontainer.dirty_pages_supported &&
350         !vbasedev->iommu_dirty_tracking) {
351         warn_report("IOMMU instance for device %s doesn't support dirty tracking",
352                     vbasedev->name);
353     }
354     return true;
355 }
356 
357 static void iommufd_cdev_autodomains_put(VFIODevice *vbasedev,
358                                          VFIOIOMMUFDContainer *container)
359 {
360     VFIOIOASHwpt *hwpt = vbasedev->hwpt;
361 
362     QLIST_REMOVE(vbasedev, hwpt_next);
363     vbasedev->hwpt = NULL;
364 
365     if (QLIST_EMPTY(&hwpt->device_list)) {
366         QLIST_REMOVE(hwpt, next);
367         iommufd_backend_free_id(container->be, hwpt->hwpt_id);
368         g_free(hwpt);
369     }
370 }
371 
372 static bool iommufd_cdev_attach_container(VFIODevice *vbasedev,
373                                           VFIOIOMMUFDContainer *container,
374                                           Error **errp)
375 {
376     /* mdevs aren't physical devices and will fail with auto domains */
377     if (!vbasedev->mdev) {
378         return iommufd_cdev_autodomains_get(vbasedev, container, errp);
379     }
380 
381     return !iommufd_cdev_attach_ioas_hwpt(vbasedev, container->ioas_id, errp);
382 }
383 
384 static void iommufd_cdev_detach_container(VFIODevice *vbasedev,
385                                           VFIOIOMMUFDContainer *container)
386 {
387     Error *err = NULL;
388 
389     if (!iommufd_cdev_detach_ioas_hwpt(vbasedev, &err)) {
390         error_report_err(err);
391     }
392 
393     if (vbasedev->hwpt) {
394         iommufd_cdev_autodomains_put(vbasedev, container);
395     }
396 
397 }
398 
399 static void iommufd_cdev_container_destroy(VFIOIOMMUFDContainer *container)
400 {
401     VFIOContainerBase *bcontainer = &container->bcontainer;
402 
403     if (!QLIST_EMPTY(&bcontainer->device_list)) {
404         return;
405     }
406     memory_listener_unregister(&bcontainer->listener);
407     iommufd_backend_free_id(container->be, container->ioas_id);
408     object_unref(container);
409 }
410 
411 static int iommufd_cdev_ram_block_discard_disable(bool state)
412 {
413     /*
414      * We support coordinated discarding of RAM via the RamDiscardManager.
415      */
416     return ram_block_uncoordinated_discard_disable(state);
417 }
418 
419 static bool iommufd_cdev_get_info_iova_range(VFIOIOMMUFDContainer *container,
420                                              uint32_t ioas_id, Error **errp)
421 {
422     VFIOContainerBase *bcontainer = &container->bcontainer;
423     g_autofree struct iommu_ioas_iova_ranges *info = NULL;
424     struct iommu_iova_range *iova_ranges;
425     int sz, fd = container->be->fd;
426 
427     info = g_malloc0(sizeof(*info));
428     info->size = sizeof(*info);
429     info->ioas_id = ioas_id;
430 
431     if (ioctl(fd, IOMMU_IOAS_IOVA_RANGES, info) && errno != EMSGSIZE) {
432         goto error;
433     }
434 
435     sz = info->num_iovas * sizeof(struct iommu_iova_range);
436     info = g_realloc(info, sizeof(*info) + sz);
437     info->allowed_iovas = (uintptr_t)(info + 1);
438 
439     if (ioctl(fd, IOMMU_IOAS_IOVA_RANGES, info)) {
440         goto error;
441     }
442 
443     iova_ranges = (struct iommu_iova_range *)(uintptr_t)info->allowed_iovas;
444 
445     for (int i = 0; i < info->num_iovas; i++) {
446         Range *range = g_new(Range, 1);
447 
448         range_set_bounds(range, iova_ranges[i].start, iova_ranges[i].last);
449         bcontainer->iova_ranges =
450             range_list_insert(bcontainer->iova_ranges, range);
451     }
452     bcontainer->pgsizes = info->out_iova_alignment;
453 
454     return true;
455 
456 error:
457     error_setg_errno(errp, errno, "Cannot get IOVA ranges");
458     return false;
459 }
460 
461 static bool iommufd_cdev_attach(const char *name, VFIODevice *vbasedev,
462                                 AddressSpace *as, Error **errp)
463 {
464     VFIOContainerBase *bcontainer;
465     VFIOIOMMUFDContainer *container;
466     VFIOAddressSpace *space;
467     struct vfio_device_info dev_info = { .argsz = sizeof(dev_info) };
468     int ret, devfd;
469     uint32_t ioas_id;
470     Error *err = NULL;
471     const VFIOIOMMUClass *iommufd_vioc =
472         VFIO_IOMMU_CLASS(object_class_by_name(TYPE_VFIO_IOMMU_IOMMUFD));
473 
474     if (vbasedev->fd < 0) {
475         devfd = iommufd_cdev_getfd(vbasedev->sysfsdev, errp);
476         if (devfd < 0) {
477             return false;
478         }
479         vbasedev->fd = devfd;
480     } else {
481         devfd = vbasedev->fd;
482     }
483 
484     if (!iommufd_cdev_connect_and_bind(vbasedev, errp)) {
485         goto err_connect_bind;
486     }
487 
488     space = vfio_get_address_space(as);
489 
490     /*
491      * The HostIOMMUDevice data from legacy backend is static and doesn't need
492      * any information from the (type1-iommu) backend to be initialized. In
493      * contrast however, the IOMMUFD HostIOMMUDevice data requires the iommufd
494      * FD to be connected and having a devid to be able to successfully call
495      * iommufd_backend_get_device_info().
496      */
497     if (!vfio_device_hiod_realize(vbasedev, errp)) {
498         goto err_alloc_ioas;
499     }
500 
501     /* try to attach to an existing container in this space */
502     QLIST_FOREACH(bcontainer, &space->containers, next) {
503         container = container_of(bcontainer, VFIOIOMMUFDContainer, bcontainer);
504         if (VFIO_IOMMU_GET_CLASS(bcontainer) != iommufd_vioc ||
505             vbasedev->iommufd != container->be) {
506             continue;
507         }
508         if (!iommufd_cdev_attach_container(vbasedev, container, &err)) {
509             const char *msg = error_get_pretty(err);
510 
511             trace_iommufd_cdev_fail_attach_existing_container(msg);
512             error_free(err);
513             err = NULL;
514         } else {
515             ret = iommufd_cdev_ram_block_discard_disable(true);
516             if (ret) {
517                 error_setg_errno(errp, -ret,
518                                  "Cannot set discarding of RAM broken");
519                 goto err_discard_disable;
520             }
521             goto found_container;
522         }
523     }
524 
525     /* Need to allocate a new dedicated container */
526     if (!iommufd_backend_alloc_ioas(vbasedev->iommufd, &ioas_id, errp)) {
527         goto err_alloc_ioas;
528     }
529 
530     trace_iommufd_cdev_alloc_ioas(vbasedev->iommufd->fd, ioas_id);
531 
532     container = VFIO_IOMMU_IOMMUFD(object_new(TYPE_VFIO_IOMMU_IOMMUFD));
533     container->be = vbasedev->iommufd;
534     container->ioas_id = ioas_id;
535     QLIST_INIT(&container->hwpt_list);
536 
537     bcontainer = &container->bcontainer;
538     vfio_address_space_insert(space, bcontainer);
539 
540     if (!iommufd_cdev_attach_container(vbasedev, container, errp)) {
541         goto err_attach_container;
542     }
543 
544     ret = iommufd_cdev_ram_block_discard_disable(true);
545     if (ret) {
546         error_setg_errno(errp, -ret, "Cannot set discarding of RAM broken");
547         goto err_discard_disable;
548     }
549 
550     if (!iommufd_cdev_get_info_iova_range(container, ioas_id, &err)) {
551         error_append_hint(&err,
552                    "Fallback to default 64bit IOVA range and 4K page size\n");
553         warn_report_err(err);
554         err = NULL;
555         bcontainer->pgsizes = qemu_real_host_page_size();
556     }
557 
558     bcontainer->listener = vfio_memory_listener;
559     memory_listener_register(&bcontainer->listener, bcontainer->space->as);
560 
561     if (bcontainer->error) {
562         error_propagate_prepend(errp, bcontainer->error,
563                                 "memory listener initialization failed: ");
564         goto err_listener_register;
565     }
566 
567     bcontainer->initialized = true;
568 
569 found_container:
570     ret = ioctl(devfd, VFIO_DEVICE_GET_INFO, &dev_info);
571     if (ret) {
572         error_setg_errno(errp, errno, "error getting device info");
573         goto err_listener_register;
574     }
575 
576     if (!vfio_cpr_register_container(bcontainer, errp)) {
577         goto err_listener_register;
578     }
579 
580     /*
581      * TODO: examine RAM_BLOCK_DISCARD stuff, should we do group level
582      * for discarding incompatibility check as well?
583      */
584     if (vbasedev->ram_block_discard_allowed) {
585         iommufd_cdev_ram_block_discard_disable(false);
586     }
587 
588     vbasedev->group = 0;
589     vbasedev->num_irqs = dev_info.num_irqs;
590     vbasedev->num_regions = dev_info.num_regions;
591     vbasedev->flags = dev_info.flags;
592     vbasedev->reset_works = !!(dev_info.flags & VFIO_DEVICE_FLAGS_RESET);
593     vbasedev->bcontainer = bcontainer;
594     QLIST_INSERT_HEAD(&bcontainer->device_list, vbasedev, container_next);
595     QLIST_INSERT_HEAD(&vfio_device_list, vbasedev, global_next);
596 
597     trace_iommufd_cdev_device_info(vbasedev->name, devfd, vbasedev->num_irqs,
598                                    vbasedev->num_regions, vbasedev->flags);
599     return true;
600 
601 err_listener_register:
602     iommufd_cdev_ram_block_discard_disable(false);
603 err_discard_disable:
604     iommufd_cdev_detach_container(vbasedev, container);
605 err_attach_container:
606     iommufd_cdev_container_destroy(container);
607 err_alloc_ioas:
608     vfio_put_address_space(space);
609     iommufd_cdev_unbind_and_disconnect(vbasedev);
610 err_connect_bind:
611     close(vbasedev->fd);
612     return false;
613 }
614 
615 static void iommufd_cdev_detach(VFIODevice *vbasedev)
616 {
617     VFIOContainerBase *bcontainer = vbasedev->bcontainer;
618     VFIOAddressSpace *space = bcontainer->space;
619     VFIOIOMMUFDContainer *container = container_of(bcontainer,
620                                                    VFIOIOMMUFDContainer,
621                                                    bcontainer);
622     QLIST_REMOVE(vbasedev, global_next);
623     QLIST_REMOVE(vbasedev, container_next);
624     vbasedev->bcontainer = NULL;
625 
626     if (!vbasedev->ram_block_discard_allowed) {
627         iommufd_cdev_ram_block_discard_disable(false);
628     }
629 
630     vfio_cpr_unregister_container(bcontainer);
631     iommufd_cdev_detach_container(vbasedev, container);
632     iommufd_cdev_container_destroy(container);
633     vfio_put_address_space(space);
634 
635     iommufd_cdev_unbind_and_disconnect(vbasedev);
636     close(vbasedev->fd);
637 }
638 
639 static VFIODevice *iommufd_cdev_pci_find_by_devid(__u32 devid)
640 {
641     VFIODevice *vbasedev_iter;
642     const VFIOIOMMUClass *iommufd_vioc =
643         VFIO_IOMMU_CLASS(object_class_by_name(TYPE_VFIO_IOMMU_IOMMUFD));
644 
645     QLIST_FOREACH(vbasedev_iter, &vfio_device_list, global_next) {
646         if (VFIO_IOMMU_GET_CLASS(vbasedev_iter->bcontainer) != iommufd_vioc) {
647             continue;
648         }
649         if (devid == vbasedev_iter->devid) {
650             return vbasedev_iter;
651         }
652     }
653     return NULL;
654 }
655 
656 static VFIOPCIDevice *
657 iommufd_cdev_dep_get_realized_vpdev(struct vfio_pci_dependent_device *dep_dev,
658                                     VFIODevice *reset_dev)
659 {
660     VFIODevice *vbasedev_tmp;
661 
662     if (dep_dev->devid == reset_dev->devid ||
663         dep_dev->devid == VFIO_PCI_DEVID_OWNED) {
664         return NULL;
665     }
666 
667     vbasedev_tmp = iommufd_cdev_pci_find_by_devid(dep_dev->devid);
668     if (!vbasedev_tmp || !vbasedev_tmp->dev->realized ||
669         vbasedev_tmp->type != VFIO_DEVICE_TYPE_PCI) {
670         return NULL;
671     }
672 
673     return container_of(vbasedev_tmp, VFIOPCIDevice, vbasedev);
674 }
675 
676 static int iommufd_cdev_pci_hot_reset(VFIODevice *vbasedev, bool single)
677 {
678     VFIOPCIDevice *vdev = container_of(vbasedev, VFIOPCIDevice, vbasedev);
679     struct vfio_pci_hot_reset_info *info = NULL;
680     struct vfio_pci_dependent_device *devices;
681     struct vfio_pci_hot_reset *reset;
682     int ret, i;
683     bool multi = false;
684 
685     trace_vfio_pci_hot_reset(vdev->vbasedev.name, single ? "one" : "multi");
686 
687     if (!single) {
688         vfio_pci_pre_reset(vdev);
689     }
690     vdev->vbasedev.needs_reset = false;
691 
692     ret = vfio_pci_get_pci_hot_reset_info(vdev, &info);
693 
694     if (ret) {
695         goto out_single;
696     }
697 
698     assert(info->flags & VFIO_PCI_HOT_RESET_FLAG_DEV_ID);
699 
700     devices = &info->devices[0];
701 
702     if (!(info->flags & VFIO_PCI_HOT_RESET_FLAG_DEV_ID_OWNED)) {
703         if (!vdev->has_pm_reset) {
704             for (i = 0; i < info->count; i++) {
705                 if (devices[i].devid == VFIO_PCI_DEVID_NOT_OWNED) {
706                     error_report("vfio: Cannot reset device %s, "
707                                  "depends on device %04x:%02x:%02x.%x "
708                                  "which is not owned.",
709                                  vdev->vbasedev.name, devices[i].segment,
710                                  devices[i].bus, PCI_SLOT(devices[i].devfn),
711                                  PCI_FUNC(devices[i].devfn));
712                 }
713             }
714         }
715         ret = -EPERM;
716         goto out_single;
717     }
718 
719     trace_vfio_pci_hot_reset_has_dep_devices(vdev->vbasedev.name);
720 
721     for (i = 0; i < info->count; i++) {
722         VFIOPCIDevice *tmp;
723 
724         trace_iommufd_cdev_pci_hot_reset_dep_devices(devices[i].segment,
725                                                      devices[i].bus,
726                                                      PCI_SLOT(devices[i].devfn),
727                                                      PCI_FUNC(devices[i].devfn),
728                                                      devices[i].devid);
729 
730         /*
731          * If a VFIO cdev device is resettable, all the dependent devices
732          * are either bound to same iommufd or within same iommu_groups as
733          * one of the iommufd bound devices.
734          */
735         assert(devices[i].devid != VFIO_PCI_DEVID_NOT_OWNED);
736 
737         tmp = iommufd_cdev_dep_get_realized_vpdev(&devices[i], &vdev->vbasedev);
738         if (!tmp) {
739             continue;
740         }
741 
742         if (single) {
743             ret = -EINVAL;
744             goto out_single;
745         }
746         vfio_pci_pre_reset(tmp);
747         tmp->vbasedev.needs_reset = false;
748         multi = true;
749     }
750 
751     if (!single && !multi) {
752         ret = -EINVAL;
753         goto out_single;
754     }
755 
756     /* Use zero length array for hot reset with iommufd backend */
757     reset = g_malloc0(sizeof(*reset));
758     reset->argsz = sizeof(*reset);
759 
760      /* Bus reset! */
761     ret = ioctl(vdev->vbasedev.fd, VFIO_DEVICE_PCI_HOT_RESET, reset);
762     g_free(reset);
763     if (ret) {
764         ret = -errno;
765     }
766 
767     trace_vfio_pci_hot_reset_result(vdev->vbasedev.name,
768                                     ret ? strerror(errno) : "Success");
769 
770     /* Re-enable INTx on affected devices */
771     for (i = 0; i < info->count; i++) {
772         VFIOPCIDevice *tmp;
773 
774         tmp = iommufd_cdev_dep_get_realized_vpdev(&devices[i], &vdev->vbasedev);
775         if (!tmp) {
776             continue;
777         }
778         vfio_pci_post_reset(tmp);
779     }
780 out_single:
781     if (!single) {
782         vfio_pci_post_reset(vdev);
783     }
784     g_free(info);
785 
786     return ret;
787 }
788 
789 static void vfio_iommu_iommufd_class_init(ObjectClass *klass, void *data)
790 {
791     VFIOIOMMUClass *vioc = VFIO_IOMMU_CLASS(klass);
792 
793     vioc->hiod_typename = TYPE_HOST_IOMMU_DEVICE_IOMMUFD_VFIO;
794 
795     vioc->dma_map = iommufd_cdev_map;
796     vioc->dma_unmap = iommufd_cdev_unmap;
797     vioc->attach_device = iommufd_cdev_attach;
798     vioc->detach_device = iommufd_cdev_detach;
799     vioc->pci_hot_reset = iommufd_cdev_pci_hot_reset;
800     vioc->set_dirty_page_tracking = iommufd_set_dirty_page_tracking;
801     vioc->query_dirty_bitmap = iommufd_query_dirty_bitmap;
802 };
803 
804 static bool hiod_iommufd_vfio_realize(HostIOMMUDevice *hiod, void *opaque,
805                                       Error **errp)
806 {
807     VFIODevice *vdev = opaque;
808     HostIOMMUDeviceCaps *caps = &hiod->caps;
809     enum iommu_hw_info_type type;
810     union {
811         struct iommu_hw_info_vtd vtd;
812     } data;
813     uint64_t hw_caps;
814 
815     hiod->agent = opaque;
816 
817     if (!iommufd_backend_get_device_info(vdev->iommufd, vdev->devid,
818                                          &type, &data, sizeof(data),
819                                          &hw_caps, errp)) {
820         return false;
821     }
822 
823     hiod->name = g_strdup(vdev->name);
824     caps->type = type;
825     caps->hw_caps = hw_caps;
826 
827     return true;
828 }
829 
830 static GList *
831 hiod_iommufd_vfio_get_iova_ranges(HostIOMMUDevice *hiod)
832 {
833     VFIODevice *vdev = hiod->agent;
834 
835     g_assert(vdev);
836     return vfio_container_get_iova_ranges(vdev->bcontainer);
837 }
838 
839 static uint64_t
840 hiod_iommufd_vfio_get_page_size_mask(HostIOMMUDevice *hiod)
841 {
842     VFIODevice *vdev = hiod->agent;
843 
844     g_assert(vdev);
845     return vfio_container_get_page_size_mask(vdev->bcontainer);
846 }
847 
848 
849 static void hiod_iommufd_vfio_class_init(ObjectClass *oc, void *data)
850 {
851     HostIOMMUDeviceClass *hiodc = HOST_IOMMU_DEVICE_CLASS(oc);
852 
853     hiodc->realize = hiod_iommufd_vfio_realize;
854     hiodc->get_iova_ranges = hiod_iommufd_vfio_get_iova_ranges;
855     hiodc->get_page_size_mask = hiod_iommufd_vfio_get_page_size_mask;
856 };
857 
858 static const TypeInfo types[] = {
859     {
860         .name = TYPE_VFIO_IOMMU_IOMMUFD,
861         .parent = TYPE_VFIO_IOMMU,
862         .instance_size = sizeof(VFIOIOMMUFDContainer),
863         .class_init = vfio_iommu_iommufd_class_init,
864     }, {
865         .name = TYPE_HOST_IOMMU_DEVICE_IOMMUFD_VFIO,
866         .parent = TYPE_HOST_IOMMU_DEVICE_IOMMUFD,
867         .class_init = hiod_iommufd_vfio_class_init,
868     }
869 };
870 
871 DEFINE_TYPES(types)
872