xref: /openbmc/qemu/hw/vfio/common.c (revision f49986ae)
1 /*
2  * generic functions used by VFIO devices
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 CONFIG_DEVICES /* CONFIG_IOMMUFD */
23 #include <sys/ioctl.h>
24 #ifdef CONFIG_KVM
25 #include <linux/kvm.h>
26 #endif
27 #include <linux/vfio.h>
28 
29 #include "hw/vfio/vfio-common.h"
30 #include "hw/vfio/pci.h"
31 #include "exec/address-spaces.h"
32 #include "exec/memory.h"
33 #include "exec/ram_addr.h"
34 #include "hw/hw.h"
35 #include "qemu/error-report.h"
36 #include "qemu/main-loop.h"
37 #include "qemu/range.h"
38 #include "sysemu/kvm.h"
39 #include "sysemu/reset.h"
40 #include "sysemu/runstate.h"
41 #include "trace.h"
42 #include "qapi/error.h"
43 #include "migration/migration.h"
44 #include "migration/misc.h"
45 #include "migration/blocker.h"
46 #include "migration/qemu-file.h"
47 #include "sysemu/tpm.h"
48 
49 VFIODeviceList vfio_device_list =
50     QLIST_HEAD_INITIALIZER(vfio_device_list);
51 static QLIST_HEAD(, VFIOAddressSpace) vfio_address_spaces =
52     QLIST_HEAD_INITIALIZER(vfio_address_spaces);
53 
54 #ifdef CONFIG_KVM
55 /*
56  * We have a single VFIO pseudo device per KVM VM.  Once created it lives
57  * for the life of the VM.  Closing the file descriptor only drops our
58  * reference to it and the device's reference to kvm.  Therefore once
59  * initialized, this file descriptor is only released on QEMU exit and
60  * we'll re-use it should another vfio device be attached before then.
61  */
62 int vfio_kvm_device_fd = -1;
63 #endif
64 
65 /*
66  * Device state interfaces
67  */
68 
69 bool vfio_mig_active(void)
70 {
71     VFIODevice *vbasedev;
72 
73     if (QLIST_EMPTY(&vfio_device_list)) {
74         return false;
75     }
76 
77     QLIST_FOREACH(vbasedev, &vfio_device_list, next) {
78         if (vbasedev->migration_blocker) {
79             return false;
80         }
81     }
82     return true;
83 }
84 
85 static Error *multiple_devices_migration_blocker;
86 
87 /*
88  * Multiple devices migration is allowed only if all devices support P2P
89  * migration. Single device migration is allowed regardless of P2P migration
90  * support.
91  */
92 static bool vfio_multiple_devices_migration_is_supported(void)
93 {
94     VFIODevice *vbasedev;
95     unsigned int device_num = 0;
96     bool all_support_p2p = true;
97 
98     QLIST_FOREACH(vbasedev, &vfio_device_list, next) {
99         if (vbasedev->migration) {
100             device_num++;
101 
102             if (!(vbasedev->migration->mig_flags & VFIO_MIGRATION_P2P)) {
103                 all_support_p2p = false;
104             }
105         }
106     }
107 
108     return all_support_p2p || device_num <= 1;
109 }
110 
111 int vfio_block_multiple_devices_migration(VFIODevice *vbasedev, Error **errp)
112 {
113     int ret;
114 
115     if (vfio_multiple_devices_migration_is_supported()) {
116         return 0;
117     }
118 
119     if (vbasedev->enable_migration == ON_OFF_AUTO_ON) {
120         error_setg(errp, "Multiple VFIO devices migration is supported only if "
121                          "all of them support P2P migration");
122         return -EINVAL;
123     }
124 
125     if (multiple_devices_migration_blocker) {
126         return 0;
127     }
128 
129     error_setg(&multiple_devices_migration_blocker,
130                "Multiple VFIO devices migration is supported only if all of "
131                "them support P2P migration");
132     ret = migrate_add_blocker(&multiple_devices_migration_blocker, errp);
133 
134     return ret;
135 }
136 
137 void vfio_unblock_multiple_devices_migration(void)
138 {
139     if (!multiple_devices_migration_blocker ||
140         !vfio_multiple_devices_migration_is_supported()) {
141         return;
142     }
143 
144     migrate_del_blocker(&multiple_devices_migration_blocker);
145 }
146 
147 bool vfio_viommu_preset(VFIODevice *vbasedev)
148 {
149     return vbasedev->bcontainer->space->as != &address_space_memory;
150 }
151 
152 static void vfio_set_migration_error(int err)
153 {
154     MigrationState *ms = migrate_get_current();
155 
156     if (migration_is_setup_or_active(ms->state)) {
157         WITH_QEMU_LOCK_GUARD(&ms->qemu_file_lock) {
158             if (ms->to_dst_file) {
159                 qemu_file_set_error(ms->to_dst_file, err);
160             }
161         }
162     }
163 }
164 
165 bool vfio_device_state_is_running(VFIODevice *vbasedev)
166 {
167     VFIOMigration *migration = vbasedev->migration;
168 
169     return migration->device_state == VFIO_DEVICE_STATE_RUNNING ||
170            migration->device_state == VFIO_DEVICE_STATE_RUNNING_P2P;
171 }
172 
173 bool vfio_device_state_is_precopy(VFIODevice *vbasedev)
174 {
175     VFIOMigration *migration = vbasedev->migration;
176 
177     return migration->device_state == VFIO_DEVICE_STATE_PRE_COPY ||
178            migration->device_state == VFIO_DEVICE_STATE_PRE_COPY_P2P;
179 }
180 
181 static bool vfio_devices_all_dirty_tracking(VFIOContainerBase *bcontainer)
182 {
183     VFIODevice *vbasedev;
184     MigrationState *ms = migrate_get_current();
185 
186     if (ms->state != MIGRATION_STATUS_ACTIVE &&
187         ms->state != MIGRATION_STATUS_DEVICE) {
188         return false;
189     }
190 
191     QLIST_FOREACH(vbasedev, &bcontainer->device_list, container_next) {
192         VFIOMigration *migration = vbasedev->migration;
193 
194         if (!migration) {
195             return false;
196         }
197 
198         if (vbasedev->pre_copy_dirty_page_tracking == ON_OFF_AUTO_OFF &&
199             (vfio_device_state_is_running(vbasedev) ||
200              vfio_device_state_is_precopy(vbasedev))) {
201             return false;
202         }
203     }
204     return true;
205 }
206 
207 bool vfio_devices_all_device_dirty_tracking(const VFIOContainerBase *bcontainer)
208 {
209     VFIODevice *vbasedev;
210 
211     QLIST_FOREACH(vbasedev, &bcontainer->device_list, container_next) {
212         if (!vbasedev->dirty_pages_supported) {
213             return false;
214         }
215     }
216 
217     return true;
218 }
219 
220 /*
221  * Check if all VFIO devices are running and migration is active, which is
222  * essentially equivalent to the migration being in pre-copy phase.
223  */
224 bool
225 vfio_devices_all_running_and_mig_active(const VFIOContainerBase *bcontainer)
226 {
227     VFIODevice *vbasedev;
228 
229     if (!migration_is_active(migrate_get_current())) {
230         return false;
231     }
232 
233     QLIST_FOREACH(vbasedev, &bcontainer->device_list, container_next) {
234         VFIOMigration *migration = vbasedev->migration;
235 
236         if (!migration) {
237             return false;
238         }
239 
240         if (vfio_device_state_is_running(vbasedev) ||
241             vfio_device_state_is_precopy(vbasedev)) {
242             continue;
243         } else {
244             return false;
245         }
246     }
247     return true;
248 }
249 
250 static bool vfio_listener_skipped_section(MemoryRegionSection *section)
251 {
252     return (!memory_region_is_ram(section->mr) &&
253             !memory_region_is_iommu(section->mr)) ||
254            memory_region_is_protected(section->mr) ||
255            /*
256             * Sizing an enabled 64-bit BAR can cause spurious mappings to
257             * addresses in the upper part of the 64-bit address space.  These
258             * are never accessed by the CPU and beyond the address width of
259             * some IOMMU hardware.  TODO: VFIO should tell us the IOMMU width.
260             */
261            section->offset_within_address_space & (1ULL << 63);
262 }
263 
264 /* Called with rcu_read_lock held.  */
265 static bool vfio_get_xlat_addr(IOMMUTLBEntry *iotlb, void **vaddr,
266                                ram_addr_t *ram_addr, bool *read_only)
267 {
268     bool ret, mr_has_discard_manager;
269 
270     ret = memory_get_xlat_addr(iotlb, vaddr, ram_addr, read_only,
271                                &mr_has_discard_manager);
272     if (ret && mr_has_discard_manager) {
273         /*
274          * Malicious VMs might trigger discarding of IOMMU-mapped memory. The
275          * pages will remain pinned inside vfio until unmapped, resulting in a
276          * higher memory consumption than expected. If memory would get
277          * populated again later, there would be an inconsistency between pages
278          * pinned by vfio and pages seen by QEMU. This is the case until
279          * unmapped from the IOMMU (e.g., during device reset).
280          *
281          * With malicious guests, we really only care about pinning more memory
282          * than expected. RLIMIT_MEMLOCK set for the user/process can never be
283          * exceeded and can be used to mitigate this problem.
284          */
285         warn_report_once("Using vfio with vIOMMUs and coordinated discarding of"
286                          " RAM (e.g., virtio-mem) works, however, malicious"
287                          " guests can trigger pinning of more memory than"
288                          " intended via an IOMMU. It's possible to mitigate "
289                          " by setting/adjusting RLIMIT_MEMLOCK.");
290     }
291     return ret;
292 }
293 
294 static void vfio_iommu_map_notify(IOMMUNotifier *n, IOMMUTLBEntry *iotlb)
295 {
296     VFIOGuestIOMMU *giommu = container_of(n, VFIOGuestIOMMU, n);
297     VFIOContainerBase *bcontainer = giommu->bcontainer;
298     hwaddr iova = iotlb->iova + giommu->iommu_offset;
299     void *vaddr;
300     int ret;
301 
302     trace_vfio_iommu_map_notify(iotlb->perm == IOMMU_NONE ? "UNMAP" : "MAP",
303                                 iova, iova + iotlb->addr_mask);
304 
305     if (iotlb->target_as != &address_space_memory) {
306         error_report("Wrong target AS \"%s\", only system memory is allowed",
307                      iotlb->target_as->name ? iotlb->target_as->name : "none");
308         vfio_set_migration_error(-EINVAL);
309         return;
310     }
311 
312     rcu_read_lock();
313 
314     if ((iotlb->perm & IOMMU_RW) != IOMMU_NONE) {
315         bool read_only;
316 
317         if (!vfio_get_xlat_addr(iotlb, &vaddr, NULL, &read_only)) {
318             goto out;
319         }
320         /*
321          * vaddr is only valid until rcu_read_unlock(). But after
322          * vfio_dma_map has set up the mapping the pages will be
323          * pinned by the kernel. This makes sure that the RAM backend
324          * of vaddr will always be there, even if the memory object is
325          * destroyed and its backing memory munmap-ed.
326          */
327         ret = vfio_container_dma_map(bcontainer, iova,
328                                      iotlb->addr_mask + 1, vaddr,
329                                      read_only);
330         if (ret) {
331             error_report("vfio_container_dma_map(%p, 0x%"HWADDR_PRIx", "
332                          "0x%"HWADDR_PRIx", %p) = %d (%s)",
333                          bcontainer, iova,
334                          iotlb->addr_mask + 1, vaddr, ret, strerror(-ret));
335         }
336     } else {
337         ret = vfio_container_dma_unmap(bcontainer, iova,
338                                        iotlb->addr_mask + 1, iotlb);
339         if (ret) {
340             error_report("vfio_container_dma_unmap(%p, 0x%"HWADDR_PRIx", "
341                          "0x%"HWADDR_PRIx") = %d (%s)",
342                          bcontainer, iova,
343                          iotlb->addr_mask + 1, ret, strerror(-ret));
344             vfio_set_migration_error(ret);
345         }
346     }
347 out:
348     rcu_read_unlock();
349 }
350 
351 static void vfio_ram_discard_notify_discard(RamDiscardListener *rdl,
352                                             MemoryRegionSection *section)
353 {
354     VFIORamDiscardListener *vrdl = container_of(rdl, VFIORamDiscardListener,
355                                                 listener);
356     VFIOContainerBase *bcontainer = vrdl->bcontainer;
357     const hwaddr size = int128_get64(section->size);
358     const hwaddr iova = section->offset_within_address_space;
359     int ret;
360 
361     /* Unmap with a single call. */
362     ret = vfio_container_dma_unmap(bcontainer, iova, size , NULL);
363     if (ret) {
364         error_report("%s: vfio_container_dma_unmap() failed: %s", __func__,
365                      strerror(-ret));
366     }
367 }
368 
369 static int vfio_ram_discard_notify_populate(RamDiscardListener *rdl,
370                                             MemoryRegionSection *section)
371 {
372     VFIORamDiscardListener *vrdl = container_of(rdl, VFIORamDiscardListener,
373                                                 listener);
374     VFIOContainerBase *bcontainer = vrdl->bcontainer;
375     const hwaddr end = section->offset_within_region +
376                        int128_get64(section->size);
377     hwaddr start, next, iova;
378     void *vaddr;
379     int ret;
380 
381     /*
382      * Map in (aligned within memory region) minimum granularity, so we can
383      * unmap in minimum granularity later.
384      */
385     for (start = section->offset_within_region; start < end; start = next) {
386         next = ROUND_UP(start + 1, vrdl->granularity);
387         next = MIN(next, end);
388 
389         iova = start - section->offset_within_region +
390                section->offset_within_address_space;
391         vaddr = memory_region_get_ram_ptr(section->mr) + start;
392 
393         ret = vfio_container_dma_map(bcontainer, iova, next - start,
394                                      vaddr, section->readonly);
395         if (ret) {
396             /* Rollback */
397             vfio_ram_discard_notify_discard(rdl, section);
398             return ret;
399         }
400     }
401     return 0;
402 }
403 
404 static void vfio_register_ram_discard_listener(VFIOContainerBase *bcontainer,
405                                                MemoryRegionSection *section)
406 {
407     RamDiscardManager *rdm = memory_region_get_ram_discard_manager(section->mr);
408     VFIORamDiscardListener *vrdl;
409 
410     /* Ignore some corner cases not relevant in practice. */
411     g_assert(QEMU_IS_ALIGNED(section->offset_within_region, TARGET_PAGE_SIZE));
412     g_assert(QEMU_IS_ALIGNED(section->offset_within_address_space,
413                              TARGET_PAGE_SIZE));
414     g_assert(QEMU_IS_ALIGNED(int128_get64(section->size), TARGET_PAGE_SIZE));
415 
416     vrdl = g_new0(VFIORamDiscardListener, 1);
417     vrdl->bcontainer = bcontainer;
418     vrdl->mr = section->mr;
419     vrdl->offset_within_address_space = section->offset_within_address_space;
420     vrdl->size = int128_get64(section->size);
421     vrdl->granularity = ram_discard_manager_get_min_granularity(rdm,
422                                                                 section->mr);
423 
424     g_assert(vrdl->granularity && is_power_of_2(vrdl->granularity));
425     g_assert(bcontainer->pgsizes &&
426              vrdl->granularity >= 1ULL << ctz64(bcontainer->pgsizes));
427 
428     ram_discard_listener_init(&vrdl->listener,
429                               vfio_ram_discard_notify_populate,
430                               vfio_ram_discard_notify_discard, true);
431     ram_discard_manager_register_listener(rdm, &vrdl->listener, section);
432     QLIST_INSERT_HEAD(&bcontainer->vrdl_list, vrdl, next);
433 
434     /*
435      * Sanity-check if we have a theoretically problematic setup where we could
436      * exceed the maximum number of possible DMA mappings over time. We assume
437      * that each mapped section in the same address space as a RamDiscardManager
438      * section consumes exactly one DMA mapping, with the exception of
439      * RamDiscardManager sections; i.e., we don't expect to have gIOMMU sections
440      * in the same address space as RamDiscardManager sections.
441      *
442      * We assume that each section in the address space consumes one memslot.
443      * We take the number of KVM memory slots as a best guess for the maximum
444      * number of sections in the address space we could have over time,
445      * also consuming DMA mappings.
446      */
447     if (bcontainer->dma_max_mappings) {
448         unsigned int vrdl_count = 0, vrdl_mappings = 0, max_memslots = 512;
449 
450 #ifdef CONFIG_KVM
451         if (kvm_enabled()) {
452             max_memslots = kvm_get_max_memslots();
453         }
454 #endif
455 
456         QLIST_FOREACH(vrdl, &bcontainer->vrdl_list, next) {
457             hwaddr start, end;
458 
459             start = QEMU_ALIGN_DOWN(vrdl->offset_within_address_space,
460                                     vrdl->granularity);
461             end = ROUND_UP(vrdl->offset_within_address_space + vrdl->size,
462                            vrdl->granularity);
463             vrdl_mappings += (end - start) / vrdl->granularity;
464             vrdl_count++;
465         }
466 
467         if (vrdl_mappings + max_memslots - vrdl_count >
468             bcontainer->dma_max_mappings) {
469             warn_report("%s: possibly running out of DMA mappings. E.g., try"
470                         " increasing the 'block-size' of virtio-mem devies."
471                         " Maximum possible DMA mappings: %d, Maximum possible"
472                         " memslots: %d", __func__, bcontainer->dma_max_mappings,
473                         max_memslots);
474         }
475     }
476 }
477 
478 static void vfio_unregister_ram_discard_listener(VFIOContainerBase *bcontainer,
479                                                  MemoryRegionSection *section)
480 {
481     RamDiscardManager *rdm = memory_region_get_ram_discard_manager(section->mr);
482     VFIORamDiscardListener *vrdl = NULL;
483 
484     QLIST_FOREACH(vrdl, &bcontainer->vrdl_list, next) {
485         if (vrdl->mr == section->mr &&
486             vrdl->offset_within_address_space ==
487             section->offset_within_address_space) {
488             break;
489         }
490     }
491 
492     if (!vrdl) {
493         hw_error("vfio: Trying to unregister missing RAM discard listener");
494     }
495 
496     ram_discard_manager_unregister_listener(rdm, &vrdl->listener);
497     QLIST_REMOVE(vrdl, next);
498     g_free(vrdl);
499 }
500 
501 static bool vfio_known_safe_misalignment(MemoryRegionSection *section)
502 {
503     MemoryRegion *mr = section->mr;
504 
505     if (!TPM_IS_CRB(mr->owner)) {
506         return false;
507     }
508 
509     /* this is a known safe misaligned region, just trace for debug purpose */
510     trace_vfio_known_safe_misalignment(memory_region_name(mr),
511                                        section->offset_within_address_space,
512                                        section->offset_within_region,
513                                        qemu_real_host_page_size());
514     return true;
515 }
516 
517 static bool vfio_listener_valid_section(MemoryRegionSection *section,
518                                         const char *name)
519 {
520     if (vfio_listener_skipped_section(section)) {
521         trace_vfio_listener_region_skip(name,
522                 section->offset_within_address_space,
523                 section->offset_within_address_space +
524                 int128_get64(int128_sub(section->size, int128_one())));
525         return false;
526     }
527 
528     if (unlikely((section->offset_within_address_space &
529                   ~qemu_real_host_page_mask()) !=
530                  (section->offset_within_region & ~qemu_real_host_page_mask()))) {
531         if (!vfio_known_safe_misalignment(section)) {
532             error_report("%s received unaligned region %s iova=0x%"PRIx64
533                          " offset_within_region=0x%"PRIx64
534                          " qemu_real_host_page_size=0x%"PRIxPTR,
535                          __func__, memory_region_name(section->mr),
536                          section->offset_within_address_space,
537                          section->offset_within_region,
538                          qemu_real_host_page_size());
539         }
540         return false;
541     }
542 
543     return true;
544 }
545 
546 static bool vfio_get_section_iova_range(VFIOContainerBase *bcontainer,
547                                         MemoryRegionSection *section,
548                                         hwaddr *out_iova, hwaddr *out_end,
549                                         Int128 *out_llend)
550 {
551     Int128 llend;
552     hwaddr iova;
553 
554     iova = REAL_HOST_PAGE_ALIGN(section->offset_within_address_space);
555     llend = int128_make64(section->offset_within_address_space);
556     llend = int128_add(llend, section->size);
557     llend = int128_and(llend, int128_exts64(qemu_real_host_page_mask()));
558 
559     if (int128_ge(int128_make64(iova), llend)) {
560         return false;
561     }
562 
563     *out_iova = iova;
564     *out_end = int128_get64(int128_sub(llend, int128_one()));
565     if (out_llend) {
566         *out_llend = llend;
567     }
568     return true;
569 }
570 
571 static void vfio_listener_region_add(MemoryListener *listener,
572                                      MemoryRegionSection *section)
573 {
574     VFIOContainerBase *bcontainer = container_of(listener, VFIOContainerBase,
575                                                  listener);
576     hwaddr iova, end;
577     Int128 llend, llsize;
578     void *vaddr;
579     int ret;
580     Error *err = NULL;
581 
582     if (!vfio_listener_valid_section(section, "region_add")) {
583         return;
584     }
585 
586     if (!vfio_get_section_iova_range(bcontainer, section, &iova, &end,
587                                      &llend)) {
588         if (memory_region_is_ram_device(section->mr)) {
589             trace_vfio_listener_region_add_no_dma_map(
590                 memory_region_name(section->mr),
591                 section->offset_within_address_space,
592                 int128_getlo(section->size),
593                 qemu_real_host_page_size());
594         }
595         return;
596     }
597 
598     if (vfio_container_add_section_window(bcontainer, section, &err)) {
599         goto fail;
600     }
601 
602     memory_region_ref(section->mr);
603 
604     if (memory_region_is_iommu(section->mr)) {
605         VFIOGuestIOMMU *giommu;
606         IOMMUMemoryRegion *iommu_mr = IOMMU_MEMORY_REGION(section->mr);
607         int iommu_idx;
608 
609         trace_vfio_listener_region_add_iommu(iova, end);
610         /*
611          * FIXME: For VFIO iommu types which have KVM acceleration to
612          * avoid bouncing all map/unmaps through qemu this way, this
613          * would be the right place to wire that up (tell the KVM
614          * device emulation the VFIO iommu handles to use).
615          */
616         giommu = g_malloc0(sizeof(*giommu));
617         giommu->iommu_mr = iommu_mr;
618         giommu->iommu_offset = section->offset_within_address_space -
619                                section->offset_within_region;
620         giommu->bcontainer = bcontainer;
621         llend = int128_add(int128_make64(section->offset_within_region),
622                            section->size);
623         llend = int128_sub(llend, int128_one());
624         iommu_idx = memory_region_iommu_attrs_to_index(iommu_mr,
625                                                        MEMTXATTRS_UNSPECIFIED);
626         iommu_notifier_init(&giommu->n, vfio_iommu_map_notify,
627                             IOMMU_NOTIFIER_IOTLB_EVENTS,
628                             section->offset_within_region,
629                             int128_get64(llend),
630                             iommu_idx);
631 
632         ret = memory_region_iommu_set_page_size_mask(giommu->iommu_mr,
633                                                      bcontainer->pgsizes,
634                                                      &err);
635         if (ret) {
636             g_free(giommu);
637             goto fail;
638         }
639 
640         if (bcontainer->iova_ranges) {
641             ret = memory_region_iommu_set_iova_ranges(giommu->iommu_mr,
642                                                       bcontainer->iova_ranges,
643                                                       &err);
644             if (ret) {
645                 g_free(giommu);
646                 goto fail;
647             }
648         }
649 
650         ret = memory_region_register_iommu_notifier(section->mr, &giommu->n,
651                                                     &err);
652         if (ret) {
653             g_free(giommu);
654             goto fail;
655         }
656         QLIST_INSERT_HEAD(&bcontainer->giommu_list, giommu, giommu_next);
657         memory_region_iommu_replay(giommu->iommu_mr, &giommu->n);
658 
659         return;
660     }
661 
662     /* Here we assume that memory_region_is_ram(section->mr)==true */
663 
664     /*
665      * For RAM memory regions with a RamDiscardManager, we only want to map the
666      * actually populated parts - and update the mapping whenever we're notified
667      * about changes.
668      */
669     if (memory_region_has_ram_discard_manager(section->mr)) {
670         vfio_register_ram_discard_listener(bcontainer, section);
671         return;
672     }
673 
674     vaddr = memory_region_get_ram_ptr(section->mr) +
675             section->offset_within_region +
676             (iova - section->offset_within_address_space);
677 
678     trace_vfio_listener_region_add_ram(iova, end, vaddr);
679 
680     llsize = int128_sub(llend, int128_make64(iova));
681 
682     if (memory_region_is_ram_device(section->mr)) {
683         hwaddr pgmask = (1ULL << ctz64(bcontainer->pgsizes)) - 1;
684 
685         if ((iova & pgmask) || (int128_get64(llsize) & pgmask)) {
686             trace_vfio_listener_region_add_no_dma_map(
687                 memory_region_name(section->mr),
688                 section->offset_within_address_space,
689                 int128_getlo(section->size),
690                 pgmask + 1);
691             return;
692         }
693     }
694 
695     ret = vfio_container_dma_map(bcontainer, iova, int128_get64(llsize),
696                                  vaddr, section->readonly);
697     if (ret) {
698         error_setg(&err, "vfio_container_dma_map(%p, 0x%"HWADDR_PRIx", "
699                    "0x%"HWADDR_PRIx", %p) = %d (%s)",
700                    bcontainer, iova, int128_get64(llsize), vaddr, ret,
701                    strerror(-ret));
702         if (memory_region_is_ram_device(section->mr)) {
703             /* Allow unexpected mappings not to be fatal for RAM devices */
704             error_report_err(err);
705             return;
706         }
707         goto fail;
708     }
709 
710     return;
711 
712 fail:
713     if (memory_region_is_ram_device(section->mr)) {
714         error_reportf_err(err, "PCI p2p may not work: ");
715         return;
716     }
717     /*
718      * On the initfn path, store the first error in the container so we
719      * can gracefully fail.  Runtime, there's not much we can do other
720      * than throw a hardware error.
721      */
722     if (!bcontainer->initialized) {
723         if (!bcontainer->error) {
724             error_propagate_prepend(&bcontainer->error, err,
725                                     "Region %s: ",
726                                     memory_region_name(section->mr));
727         } else {
728             error_free(err);
729         }
730     } else {
731         error_report_err(err);
732         hw_error("vfio: DMA mapping failed, unable to continue");
733     }
734 }
735 
736 static void vfio_listener_region_del(MemoryListener *listener,
737                                      MemoryRegionSection *section)
738 {
739     VFIOContainerBase *bcontainer = container_of(listener, VFIOContainerBase,
740                                                  listener);
741     hwaddr iova, end;
742     Int128 llend, llsize;
743     int ret;
744     bool try_unmap = true;
745 
746     if (!vfio_listener_valid_section(section, "region_del")) {
747         return;
748     }
749 
750     if (memory_region_is_iommu(section->mr)) {
751         VFIOGuestIOMMU *giommu;
752 
753         QLIST_FOREACH(giommu, &bcontainer->giommu_list, giommu_next) {
754             if (MEMORY_REGION(giommu->iommu_mr) == section->mr &&
755                 giommu->n.start == section->offset_within_region) {
756                 memory_region_unregister_iommu_notifier(section->mr,
757                                                         &giommu->n);
758                 QLIST_REMOVE(giommu, giommu_next);
759                 g_free(giommu);
760                 break;
761             }
762         }
763 
764         /*
765          * FIXME: We assume the one big unmap below is adequate to
766          * remove any individual page mappings in the IOMMU which
767          * might have been copied into VFIO. This works for a page table
768          * based IOMMU where a big unmap flattens a large range of IO-PTEs.
769          * That may not be true for all IOMMU types.
770          */
771     }
772 
773     if (!vfio_get_section_iova_range(bcontainer, section, &iova, &end,
774                                      &llend)) {
775         return;
776     }
777 
778     llsize = int128_sub(llend, int128_make64(iova));
779 
780     trace_vfio_listener_region_del(iova, end);
781 
782     if (memory_region_is_ram_device(section->mr)) {
783         hwaddr pgmask;
784 
785         pgmask = (1ULL << ctz64(bcontainer->pgsizes)) - 1;
786         try_unmap = !((iova & pgmask) || (int128_get64(llsize) & pgmask));
787     } else if (memory_region_has_ram_discard_manager(section->mr)) {
788         vfio_unregister_ram_discard_listener(bcontainer, section);
789         /* Unregistering will trigger an unmap. */
790         try_unmap = false;
791     }
792 
793     if (try_unmap) {
794         if (int128_eq(llsize, int128_2_64())) {
795             /* The unmap ioctl doesn't accept a full 64-bit span. */
796             llsize = int128_rshift(llsize, 1);
797             ret = vfio_container_dma_unmap(bcontainer, iova,
798                                            int128_get64(llsize), NULL);
799             if (ret) {
800                 error_report("vfio_container_dma_unmap(%p, 0x%"HWADDR_PRIx", "
801                              "0x%"HWADDR_PRIx") = %d (%s)",
802                              bcontainer, iova, int128_get64(llsize), ret,
803                              strerror(-ret));
804             }
805             iova += int128_get64(llsize);
806         }
807         ret = vfio_container_dma_unmap(bcontainer, iova,
808                                        int128_get64(llsize), NULL);
809         if (ret) {
810             error_report("vfio_container_dma_unmap(%p, 0x%"HWADDR_PRIx", "
811                          "0x%"HWADDR_PRIx") = %d (%s)",
812                          bcontainer, iova, int128_get64(llsize), ret,
813                          strerror(-ret));
814         }
815     }
816 
817     memory_region_unref(section->mr);
818 
819     vfio_container_del_section_window(bcontainer, section);
820 }
821 
822 typedef struct VFIODirtyRanges {
823     hwaddr min32;
824     hwaddr max32;
825     hwaddr min64;
826     hwaddr max64;
827     hwaddr minpci64;
828     hwaddr maxpci64;
829 } VFIODirtyRanges;
830 
831 typedef struct VFIODirtyRangesListener {
832     VFIOContainerBase *bcontainer;
833     VFIODirtyRanges ranges;
834     MemoryListener listener;
835 } VFIODirtyRangesListener;
836 
837 static bool vfio_section_is_vfio_pci(MemoryRegionSection *section,
838                                      VFIOContainerBase *bcontainer)
839 {
840     VFIOPCIDevice *pcidev;
841     VFIODevice *vbasedev;
842     Object *owner;
843 
844     owner = memory_region_owner(section->mr);
845 
846     QLIST_FOREACH(vbasedev, &bcontainer->device_list, container_next) {
847         if (vbasedev->type != VFIO_DEVICE_TYPE_PCI) {
848             continue;
849         }
850         pcidev = container_of(vbasedev, VFIOPCIDevice, vbasedev);
851         if (OBJECT(pcidev) == owner) {
852             return true;
853         }
854     }
855 
856     return false;
857 }
858 
859 static void vfio_dirty_tracking_update(MemoryListener *listener,
860                                        MemoryRegionSection *section)
861 {
862     VFIODirtyRangesListener *dirty = container_of(listener,
863                                                   VFIODirtyRangesListener,
864                                                   listener);
865     VFIODirtyRanges *range = &dirty->ranges;
866     hwaddr iova, end, *min, *max;
867 
868     if (!vfio_listener_valid_section(section, "tracking_update") ||
869         !vfio_get_section_iova_range(dirty->bcontainer, section,
870                                      &iova, &end, NULL)) {
871         return;
872     }
873 
874     /*
875      * The address space passed to the dirty tracker is reduced to three ranges:
876      * one for 32-bit DMA ranges, one for 64-bit DMA ranges and one for the
877      * PCI 64-bit hole.
878      *
879      * The underlying reports of dirty will query a sub-interval of each of
880      * these ranges.
881      *
882      * The purpose of the three range handling is to handle known cases of big
883      * holes in the address space, like the x86 AMD 1T hole, and firmware (like
884      * OVMF) which may relocate the pci-hole64 to the end of the address space.
885      * The latter would otherwise generate large ranges for tracking, stressing
886      * the limits of supported hardware. The pci-hole32 will always be below 4G
887      * (overlapping or not) so it doesn't need special handling and is part of
888      * the 32-bit range.
889      *
890      * The alternative would be an IOVATree but that has a much bigger runtime
891      * overhead and unnecessary complexity.
892      */
893     if (vfio_section_is_vfio_pci(section, dirty->bcontainer) &&
894         iova >= UINT32_MAX) {
895         min = &range->minpci64;
896         max = &range->maxpci64;
897     } else {
898         min = (end <= UINT32_MAX) ? &range->min32 : &range->min64;
899         max = (end <= UINT32_MAX) ? &range->max32 : &range->max64;
900     }
901     if (*min > iova) {
902         *min = iova;
903     }
904     if (*max < end) {
905         *max = end;
906     }
907 
908     trace_vfio_device_dirty_tracking_update(iova, end, *min, *max);
909     return;
910 }
911 
912 static const MemoryListener vfio_dirty_tracking_listener = {
913     .name = "vfio-tracking",
914     .region_add = vfio_dirty_tracking_update,
915 };
916 
917 static void vfio_dirty_tracking_init(VFIOContainerBase *bcontainer,
918                                      VFIODirtyRanges *ranges)
919 {
920     VFIODirtyRangesListener dirty;
921 
922     memset(&dirty, 0, sizeof(dirty));
923     dirty.ranges.min32 = UINT32_MAX;
924     dirty.ranges.min64 = UINT64_MAX;
925     dirty.ranges.minpci64 = UINT64_MAX;
926     dirty.listener = vfio_dirty_tracking_listener;
927     dirty.bcontainer = bcontainer;
928 
929     memory_listener_register(&dirty.listener,
930                              bcontainer->space->as);
931 
932     *ranges = dirty.ranges;
933 
934     /*
935      * The memory listener is synchronous, and used to calculate the range
936      * to dirty tracking. Unregister it after we are done as we are not
937      * interested in any follow-up updates.
938      */
939     memory_listener_unregister(&dirty.listener);
940 }
941 
942 static void vfio_devices_dma_logging_stop(VFIOContainerBase *bcontainer)
943 {
944     uint64_t buf[DIV_ROUND_UP(sizeof(struct vfio_device_feature),
945                               sizeof(uint64_t))] = {};
946     struct vfio_device_feature *feature = (struct vfio_device_feature *)buf;
947     VFIODevice *vbasedev;
948 
949     feature->argsz = sizeof(buf);
950     feature->flags = VFIO_DEVICE_FEATURE_SET |
951                      VFIO_DEVICE_FEATURE_DMA_LOGGING_STOP;
952 
953     QLIST_FOREACH(vbasedev, &bcontainer->device_list, container_next) {
954         if (!vbasedev->dirty_tracking) {
955             continue;
956         }
957 
958         if (ioctl(vbasedev->fd, VFIO_DEVICE_FEATURE, feature)) {
959             warn_report("%s: Failed to stop DMA logging, err %d (%s)",
960                         vbasedev->name, -errno, strerror(errno));
961         }
962         vbasedev->dirty_tracking = false;
963     }
964 }
965 
966 static struct vfio_device_feature *
967 vfio_device_feature_dma_logging_start_create(VFIOContainerBase *bcontainer,
968                                              VFIODirtyRanges *tracking)
969 {
970     struct vfio_device_feature *feature;
971     size_t feature_size;
972     struct vfio_device_feature_dma_logging_control *control;
973     struct vfio_device_feature_dma_logging_range *ranges;
974 
975     feature_size = sizeof(struct vfio_device_feature) +
976                    sizeof(struct vfio_device_feature_dma_logging_control);
977     feature = g_try_malloc0(feature_size);
978     if (!feature) {
979         errno = ENOMEM;
980         return NULL;
981     }
982     feature->argsz = feature_size;
983     feature->flags = VFIO_DEVICE_FEATURE_SET |
984                      VFIO_DEVICE_FEATURE_DMA_LOGGING_START;
985 
986     control = (struct vfio_device_feature_dma_logging_control *)feature->data;
987     control->page_size = qemu_real_host_page_size();
988 
989     /*
990      * DMA logging uAPI guarantees to support at least a number of ranges that
991      * fits into a single host kernel base page.
992      */
993     control->num_ranges = !!tracking->max32 + !!tracking->max64 +
994         !!tracking->maxpci64;
995     ranges = g_try_new0(struct vfio_device_feature_dma_logging_range,
996                         control->num_ranges);
997     if (!ranges) {
998         g_free(feature);
999         errno = ENOMEM;
1000 
1001         return NULL;
1002     }
1003 
1004     control->ranges = (__u64)(uintptr_t)ranges;
1005     if (tracking->max32) {
1006         ranges->iova = tracking->min32;
1007         ranges->length = (tracking->max32 - tracking->min32) + 1;
1008         ranges++;
1009     }
1010     if (tracking->max64) {
1011         ranges->iova = tracking->min64;
1012         ranges->length = (tracking->max64 - tracking->min64) + 1;
1013         ranges++;
1014     }
1015     if (tracking->maxpci64) {
1016         ranges->iova = tracking->minpci64;
1017         ranges->length = (tracking->maxpci64 - tracking->minpci64) + 1;
1018     }
1019 
1020     trace_vfio_device_dirty_tracking_start(control->num_ranges,
1021                                            tracking->min32, tracking->max32,
1022                                            tracking->min64, tracking->max64,
1023                                            tracking->minpci64, tracking->maxpci64);
1024 
1025     return feature;
1026 }
1027 
1028 static void vfio_device_feature_dma_logging_start_destroy(
1029     struct vfio_device_feature *feature)
1030 {
1031     struct vfio_device_feature_dma_logging_control *control =
1032         (struct vfio_device_feature_dma_logging_control *)feature->data;
1033     struct vfio_device_feature_dma_logging_range *ranges =
1034         (struct vfio_device_feature_dma_logging_range *)(uintptr_t)control->ranges;
1035 
1036     g_free(ranges);
1037     g_free(feature);
1038 }
1039 
1040 static int vfio_devices_dma_logging_start(VFIOContainerBase *bcontainer)
1041 {
1042     struct vfio_device_feature *feature;
1043     VFIODirtyRanges ranges;
1044     VFIODevice *vbasedev;
1045     int ret = 0;
1046 
1047     vfio_dirty_tracking_init(bcontainer, &ranges);
1048     feature = vfio_device_feature_dma_logging_start_create(bcontainer,
1049                                                            &ranges);
1050     if (!feature) {
1051         return -errno;
1052     }
1053 
1054     QLIST_FOREACH(vbasedev, &bcontainer->device_list, container_next) {
1055         if (vbasedev->dirty_tracking) {
1056             continue;
1057         }
1058 
1059         ret = ioctl(vbasedev->fd, VFIO_DEVICE_FEATURE, feature);
1060         if (ret) {
1061             ret = -errno;
1062             error_report("%s: Failed to start DMA logging, err %d (%s)",
1063                          vbasedev->name, ret, strerror(errno));
1064             goto out;
1065         }
1066         vbasedev->dirty_tracking = true;
1067     }
1068 
1069 out:
1070     if (ret) {
1071         vfio_devices_dma_logging_stop(bcontainer);
1072     }
1073 
1074     vfio_device_feature_dma_logging_start_destroy(feature);
1075 
1076     return ret;
1077 }
1078 
1079 static void vfio_listener_log_global_start(MemoryListener *listener)
1080 {
1081     VFIOContainerBase *bcontainer = container_of(listener, VFIOContainerBase,
1082                                                  listener);
1083     int ret;
1084 
1085     if (vfio_devices_all_device_dirty_tracking(bcontainer)) {
1086         ret = vfio_devices_dma_logging_start(bcontainer);
1087     } else {
1088         ret = vfio_container_set_dirty_page_tracking(bcontainer, true);
1089     }
1090 
1091     if (ret) {
1092         error_report("vfio: Could not start dirty page tracking, err: %d (%s)",
1093                      ret, strerror(-ret));
1094         vfio_set_migration_error(ret);
1095     }
1096 }
1097 
1098 static void vfio_listener_log_global_stop(MemoryListener *listener)
1099 {
1100     VFIOContainerBase *bcontainer = container_of(listener, VFIOContainerBase,
1101                                                  listener);
1102     int ret = 0;
1103 
1104     if (vfio_devices_all_device_dirty_tracking(bcontainer)) {
1105         vfio_devices_dma_logging_stop(bcontainer);
1106     } else {
1107         ret = vfio_container_set_dirty_page_tracking(bcontainer, false);
1108     }
1109 
1110     if (ret) {
1111         error_report("vfio: Could not stop dirty page tracking, err: %d (%s)",
1112                      ret, strerror(-ret));
1113         vfio_set_migration_error(ret);
1114     }
1115 }
1116 
1117 static int vfio_device_dma_logging_report(VFIODevice *vbasedev, hwaddr iova,
1118                                           hwaddr size, void *bitmap)
1119 {
1120     uint64_t buf[DIV_ROUND_UP(sizeof(struct vfio_device_feature) +
1121                         sizeof(struct vfio_device_feature_dma_logging_report),
1122                         sizeof(__u64))] = {};
1123     struct vfio_device_feature *feature = (struct vfio_device_feature *)buf;
1124     struct vfio_device_feature_dma_logging_report *report =
1125         (struct vfio_device_feature_dma_logging_report *)feature->data;
1126 
1127     report->iova = iova;
1128     report->length = size;
1129     report->page_size = qemu_real_host_page_size();
1130     report->bitmap = (__u64)(uintptr_t)bitmap;
1131 
1132     feature->argsz = sizeof(buf);
1133     feature->flags = VFIO_DEVICE_FEATURE_GET |
1134                      VFIO_DEVICE_FEATURE_DMA_LOGGING_REPORT;
1135 
1136     if (ioctl(vbasedev->fd, VFIO_DEVICE_FEATURE, feature)) {
1137         return -errno;
1138     }
1139 
1140     return 0;
1141 }
1142 
1143 int vfio_devices_query_dirty_bitmap(const VFIOContainerBase *bcontainer,
1144                                     VFIOBitmap *vbmap, hwaddr iova,
1145                                     hwaddr size)
1146 {
1147     VFIODevice *vbasedev;
1148     int ret;
1149 
1150     QLIST_FOREACH(vbasedev, &bcontainer->device_list, container_next) {
1151         ret = vfio_device_dma_logging_report(vbasedev, iova, size,
1152                                              vbmap->bitmap);
1153         if (ret) {
1154             error_report("%s: Failed to get DMA logging report, iova: "
1155                          "0x%" HWADDR_PRIx ", size: 0x%" HWADDR_PRIx
1156                          ", err: %d (%s)",
1157                          vbasedev->name, iova, size, ret, strerror(-ret));
1158 
1159             return ret;
1160         }
1161     }
1162 
1163     return 0;
1164 }
1165 
1166 int vfio_get_dirty_bitmap(const VFIOContainerBase *bcontainer, uint64_t iova,
1167                           uint64_t size, ram_addr_t ram_addr)
1168 {
1169     bool all_device_dirty_tracking =
1170         vfio_devices_all_device_dirty_tracking(bcontainer);
1171     uint64_t dirty_pages;
1172     VFIOBitmap vbmap;
1173     int ret;
1174 
1175     if (!bcontainer->dirty_pages_supported && !all_device_dirty_tracking) {
1176         cpu_physical_memory_set_dirty_range(ram_addr, size,
1177                                             tcg_enabled() ? DIRTY_CLIENTS_ALL :
1178                                             DIRTY_CLIENTS_NOCODE);
1179         return 0;
1180     }
1181 
1182     ret = vfio_bitmap_alloc(&vbmap, size);
1183     if (ret) {
1184         return ret;
1185     }
1186 
1187     if (all_device_dirty_tracking) {
1188         ret = vfio_devices_query_dirty_bitmap(bcontainer, &vbmap, iova, size);
1189     } else {
1190         ret = vfio_container_query_dirty_bitmap(bcontainer, &vbmap, iova, size);
1191     }
1192 
1193     if (ret) {
1194         goto out;
1195     }
1196 
1197     dirty_pages = cpu_physical_memory_set_dirty_lebitmap(vbmap.bitmap, ram_addr,
1198                                                          vbmap.pages);
1199 
1200     trace_vfio_get_dirty_bitmap(iova, size, vbmap.size, ram_addr, dirty_pages);
1201 out:
1202     g_free(vbmap.bitmap);
1203 
1204     return ret;
1205 }
1206 
1207 typedef struct {
1208     IOMMUNotifier n;
1209     VFIOGuestIOMMU *giommu;
1210 } vfio_giommu_dirty_notifier;
1211 
1212 static void vfio_iommu_map_dirty_notify(IOMMUNotifier *n, IOMMUTLBEntry *iotlb)
1213 {
1214     vfio_giommu_dirty_notifier *gdn = container_of(n,
1215                                                 vfio_giommu_dirty_notifier, n);
1216     VFIOGuestIOMMU *giommu = gdn->giommu;
1217     VFIOContainerBase *bcontainer = giommu->bcontainer;
1218     hwaddr iova = iotlb->iova + giommu->iommu_offset;
1219     ram_addr_t translated_addr;
1220     int ret = -EINVAL;
1221 
1222     trace_vfio_iommu_map_dirty_notify(iova, iova + iotlb->addr_mask);
1223 
1224     if (iotlb->target_as != &address_space_memory) {
1225         error_report("Wrong target AS \"%s\", only system memory is allowed",
1226                      iotlb->target_as->name ? iotlb->target_as->name : "none");
1227         goto out;
1228     }
1229 
1230     rcu_read_lock();
1231     if (vfio_get_xlat_addr(iotlb, NULL, &translated_addr, NULL)) {
1232         ret = vfio_get_dirty_bitmap(bcontainer, iova, iotlb->addr_mask + 1,
1233                                     translated_addr);
1234         if (ret) {
1235             error_report("vfio_iommu_map_dirty_notify(%p, 0x%"HWADDR_PRIx", "
1236                          "0x%"HWADDR_PRIx") = %d (%s)",
1237                          bcontainer, iova, iotlb->addr_mask + 1, ret,
1238                          strerror(-ret));
1239         }
1240     }
1241     rcu_read_unlock();
1242 
1243 out:
1244     if (ret) {
1245         vfio_set_migration_error(ret);
1246     }
1247 }
1248 
1249 static int vfio_ram_discard_get_dirty_bitmap(MemoryRegionSection *section,
1250                                              void *opaque)
1251 {
1252     const hwaddr size = int128_get64(section->size);
1253     const hwaddr iova = section->offset_within_address_space;
1254     const ram_addr_t ram_addr = memory_region_get_ram_addr(section->mr) +
1255                                 section->offset_within_region;
1256     VFIORamDiscardListener *vrdl = opaque;
1257 
1258     /*
1259      * Sync the whole mapped region (spanning multiple individual mappings)
1260      * in one go.
1261      */
1262     return vfio_get_dirty_bitmap(vrdl->bcontainer, iova, size, ram_addr);
1263 }
1264 
1265 static int
1266 vfio_sync_ram_discard_listener_dirty_bitmap(VFIOContainerBase *bcontainer,
1267                                             MemoryRegionSection *section)
1268 {
1269     RamDiscardManager *rdm = memory_region_get_ram_discard_manager(section->mr);
1270     VFIORamDiscardListener *vrdl = NULL;
1271 
1272     QLIST_FOREACH(vrdl, &bcontainer->vrdl_list, next) {
1273         if (vrdl->mr == section->mr &&
1274             vrdl->offset_within_address_space ==
1275             section->offset_within_address_space) {
1276             break;
1277         }
1278     }
1279 
1280     if (!vrdl) {
1281         hw_error("vfio: Trying to sync missing RAM discard listener");
1282     }
1283 
1284     /*
1285      * We only want/can synchronize the bitmap for actually mapped parts -
1286      * which correspond to populated parts. Replay all populated parts.
1287      */
1288     return ram_discard_manager_replay_populated(rdm, section,
1289                                               vfio_ram_discard_get_dirty_bitmap,
1290                                                 &vrdl);
1291 }
1292 
1293 static int vfio_sync_dirty_bitmap(VFIOContainerBase *bcontainer,
1294                                   MemoryRegionSection *section)
1295 {
1296     ram_addr_t ram_addr;
1297 
1298     if (memory_region_is_iommu(section->mr)) {
1299         VFIOGuestIOMMU *giommu;
1300 
1301         QLIST_FOREACH(giommu, &bcontainer->giommu_list, giommu_next) {
1302             if (MEMORY_REGION(giommu->iommu_mr) == section->mr &&
1303                 giommu->n.start == section->offset_within_region) {
1304                 Int128 llend;
1305                 vfio_giommu_dirty_notifier gdn = { .giommu = giommu };
1306                 int idx = memory_region_iommu_attrs_to_index(giommu->iommu_mr,
1307                                                        MEMTXATTRS_UNSPECIFIED);
1308 
1309                 llend = int128_add(int128_make64(section->offset_within_region),
1310                                    section->size);
1311                 llend = int128_sub(llend, int128_one());
1312 
1313                 iommu_notifier_init(&gdn.n,
1314                                     vfio_iommu_map_dirty_notify,
1315                                     IOMMU_NOTIFIER_MAP,
1316                                     section->offset_within_region,
1317                                     int128_get64(llend),
1318                                     idx);
1319                 memory_region_iommu_replay(giommu->iommu_mr, &gdn.n);
1320                 break;
1321             }
1322         }
1323         return 0;
1324     } else if (memory_region_has_ram_discard_manager(section->mr)) {
1325         return vfio_sync_ram_discard_listener_dirty_bitmap(bcontainer, section);
1326     }
1327 
1328     ram_addr = memory_region_get_ram_addr(section->mr) +
1329                section->offset_within_region;
1330 
1331     return vfio_get_dirty_bitmap(bcontainer,
1332                    REAL_HOST_PAGE_ALIGN(section->offset_within_address_space),
1333                    int128_get64(section->size), ram_addr);
1334 }
1335 
1336 static void vfio_listener_log_sync(MemoryListener *listener,
1337         MemoryRegionSection *section)
1338 {
1339     VFIOContainerBase *bcontainer = container_of(listener, VFIOContainerBase,
1340                                                  listener);
1341     int ret;
1342 
1343     if (vfio_listener_skipped_section(section)) {
1344         return;
1345     }
1346 
1347     if (vfio_devices_all_dirty_tracking(bcontainer)) {
1348         ret = vfio_sync_dirty_bitmap(bcontainer, section);
1349         if (ret) {
1350             error_report("vfio: Failed to sync dirty bitmap, err: %d (%s)", ret,
1351                          strerror(-ret));
1352             vfio_set_migration_error(ret);
1353         }
1354     }
1355 }
1356 
1357 const MemoryListener vfio_memory_listener = {
1358     .name = "vfio",
1359     .region_add = vfio_listener_region_add,
1360     .region_del = vfio_listener_region_del,
1361     .log_global_start = vfio_listener_log_global_start,
1362     .log_global_stop = vfio_listener_log_global_stop,
1363     .log_sync = vfio_listener_log_sync,
1364 };
1365 
1366 void vfio_reset_handler(void *opaque)
1367 {
1368     VFIODevice *vbasedev;
1369 
1370     QLIST_FOREACH(vbasedev, &vfio_device_list, next) {
1371         if (vbasedev->dev->realized) {
1372             vbasedev->ops->vfio_compute_needs_reset(vbasedev);
1373         }
1374     }
1375 
1376     QLIST_FOREACH(vbasedev, &vfio_device_list, next) {
1377         if (vbasedev->dev->realized && vbasedev->needs_reset) {
1378             vbasedev->ops->vfio_hot_reset_multi(vbasedev);
1379         }
1380     }
1381 }
1382 
1383 int vfio_kvm_device_add_fd(int fd, Error **errp)
1384 {
1385 #ifdef CONFIG_KVM
1386     struct kvm_device_attr attr = {
1387         .group = KVM_DEV_VFIO_FILE,
1388         .attr = KVM_DEV_VFIO_FILE_ADD,
1389         .addr = (uint64_t)(unsigned long)&fd,
1390     };
1391 
1392     if (!kvm_enabled()) {
1393         return 0;
1394     }
1395 
1396     if (vfio_kvm_device_fd < 0) {
1397         struct kvm_create_device cd = {
1398             .type = KVM_DEV_TYPE_VFIO,
1399         };
1400 
1401         if (kvm_vm_ioctl(kvm_state, KVM_CREATE_DEVICE, &cd)) {
1402             error_setg_errno(errp, errno, "Failed to create KVM VFIO device");
1403             return -errno;
1404         }
1405 
1406         vfio_kvm_device_fd = cd.fd;
1407     }
1408 
1409     if (ioctl(vfio_kvm_device_fd, KVM_SET_DEVICE_ATTR, &attr)) {
1410         error_setg_errno(errp, errno, "Failed to add fd %d to KVM VFIO device",
1411                          fd);
1412         return -errno;
1413     }
1414 #endif
1415     return 0;
1416 }
1417 
1418 int vfio_kvm_device_del_fd(int fd, Error **errp)
1419 {
1420 #ifdef CONFIG_KVM
1421     struct kvm_device_attr attr = {
1422         .group = KVM_DEV_VFIO_FILE,
1423         .attr = KVM_DEV_VFIO_FILE_DEL,
1424         .addr = (uint64_t)(unsigned long)&fd,
1425     };
1426 
1427     if (vfio_kvm_device_fd < 0) {
1428         error_setg(errp, "KVM VFIO device isn't created yet");
1429         return -EINVAL;
1430     }
1431 
1432     if (ioctl(vfio_kvm_device_fd, KVM_SET_DEVICE_ATTR, &attr)) {
1433         error_setg_errno(errp, errno,
1434                          "Failed to remove fd %d from KVM VFIO device", fd);
1435         return -errno;
1436     }
1437 #endif
1438     return 0;
1439 }
1440 
1441 VFIOAddressSpace *vfio_get_address_space(AddressSpace *as)
1442 {
1443     VFIOAddressSpace *space;
1444 
1445     QLIST_FOREACH(space, &vfio_address_spaces, list) {
1446         if (space->as == as) {
1447             return space;
1448         }
1449     }
1450 
1451     /* No suitable VFIOAddressSpace, create a new one */
1452     space = g_malloc0(sizeof(*space));
1453     space->as = as;
1454     QLIST_INIT(&space->containers);
1455 
1456     if (QLIST_EMPTY(&vfio_address_spaces)) {
1457         qemu_register_reset(vfio_reset_handler, NULL);
1458     }
1459 
1460     QLIST_INSERT_HEAD(&vfio_address_spaces, space, list);
1461 
1462     return space;
1463 }
1464 
1465 void vfio_put_address_space(VFIOAddressSpace *space)
1466 {
1467     if (!QLIST_EMPTY(&space->containers)) {
1468         return;
1469     }
1470 
1471     QLIST_REMOVE(space, list);
1472     g_free(space);
1473 
1474     if (QLIST_EMPTY(&vfio_address_spaces)) {
1475         qemu_unregister_reset(vfio_reset_handler, NULL);
1476     }
1477 }
1478 
1479 struct vfio_device_info *vfio_get_device_info(int fd)
1480 {
1481     struct vfio_device_info *info;
1482     uint32_t argsz = sizeof(*info);
1483 
1484     info = g_malloc0(argsz);
1485 
1486 retry:
1487     info->argsz = argsz;
1488 
1489     if (ioctl(fd, VFIO_DEVICE_GET_INFO, info)) {
1490         g_free(info);
1491         return NULL;
1492     }
1493 
1494     if (info->argsz > argsz) {
1495         argsz = info->argsz;
1496         info = g_realloc(info, argsz);
1497         goto retry;
1498     }
1499 
1500     return info;
1501 }
1502 
1503 int vfio_attach_device(char *name, VFIODevice *vbasedev,
1504                        AddressSpace *as, Error **errp)
1505 {
1506     const VFIOIOMMUOps *ops = &vfio_legacy_ops;
1507 
1508 #ifdef CONFIG_IOMMUFD
1509     if (vbasedev->iommufd) {
1510         ops = &vfio_iommufd_ops;
1511     }
1512 #endif
1513     return ops->attach_device(name, vbasedev, as, errp);
1514 }
1515 
1516 void vfio_detach_device(VFIODevice *vbasedev)
1517 {
1518     if (!vbasedev->bcontainer) {
1519         return;
1520     }
1521     vbasedev->bcontainer->ops->detach_device(vbasedev);
1522 }
1523