xref: /openbmc/qemu/hw/vfio/common.c (revision bc419a1c)
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 <sys/ioctl.h>
23 #ifdef CONFIG_KVM
24 #include <linux/kvm.h>
25 #endif
26 #include <linux/vfio.h>
27 
28 #include "hw/vfio/vfio-common.h"
29 #include "hw/vfio/pci.h"
30 #include "exec/address-spaces.h"
31 #include "exec/memory.h"
32 #include "exec/ram_addr.h"
33 #include "hw/hw.h"
34 #include "qemu/error-report.h"
35 #include "qemu/main-loop.h"
36 #include "qemu/range.h"
37 #include "sysemu/kvm.h"
38 #include "sysemu/reset.h"
39 #include "sysemu/runstate.h"
40 #include "trace.h"
41 #include "qapi/error.h"
42 #include "migration/misc.h"
43 #include "migration/blocker.h"
44 #include "migration/qemu-file.h"
45 #include "sysemu/tpm.h"
46 
47 VFIODeviceList vfio_device_list =
48     QLIST_HEAD_INITIALIZER(vfio_device_list);
49 static QLIST_HEAD(, VFIOAddressSpace) vfio_address_spaces =
50     QLIST_HEAD_INITIALIZER(vfio_address_spaces);
51 
52 #ifdef CONFIG_KVM
53 /*
54  * We have a single VFIO pseudo device per KVM VM.  Once created it lives
55  * for the life of the VM.  Closing the file descriptor only drops our
56  * reference to it and the device's reference to kvm.  Therefore once
57  * initialized, this file descriptor is only released on QEMU exit and
58  * we'll re-use it should another vfio device be attached before then.
59  */
60 int vfio_kvm_device_fd = -1;
61 #endif
62 
63 /*
64  * Device state interfaces
65  */
66 
67 bool vfio_mig_active(void)
68 {
69     VFIODevice *vbasedev;
70 
71     if (QLIST_EMPTY(&vfio_device_list)) {
72         return false;
73     }
74 
75     QLIST_FOREACH(vbasedev, &vfio_device_list, global_next) {
76         if (vbasedev->migration_blocker) {
77             return false;
78         }
79     }
80     return true;
81 }
82 
83 static Error *multiple_devices_migration_blocker;
84 
85 /*
86  * Multiple devices migration is allowed only if all devices support P2P
87  * migration. Single device migration is allowed regardless of P2P migration
88  * support.
89  */
90 static bool vfio_multiple_devices_migration_is_supported(void)
91 {
92     VFIODevice *vbasedev;
93     unsigned int device_num = 0;
94     bool all_support_p2p = true;
95 
96     QLIST_FOREACH(vbasedev, &vfio_device_list, global_next) {
97         if (vbasedev->migration) {
98             device_num++;
99 
100             if (!(vbasedev->migration->mig_flags & VFIO_MIGRATION_P2P)) {
101                 all_support_p2p = false;
102             }
103         }
104     }
105 
106     return all_support_p2p || device_num <= 1;
107 }
108 
109 int vfio_block_multiple_devices_migration(VFIODevice *vbasedev, Error **errp)
110 {
111     int ret;
112 
113     if (vfio_multiple_devices_migration_is_supported()) {
114         return 0;
115     }
116 
117     if (vbasedev->enable_migration == ON_OFF_AUTO_ON) {
118         error_setg(errp, "Multiple VFIO devices migration is supported only if "
119                          "all of them support P2P migration");
120         return -EINVAL;
121     }
122 
123     if (multiple_devices_migration_blocker) {
124         return 0;
125     }
126 
127     error_setg(&multiple_devices_migration_blocker,
128                "Multiple VFIO devices migration is supported only if all of "
129                "them support P2P migration");
130     ret = migrate_add_blocker_normal(&multiple_devices_migration_blocker, errp);
131 
132     return ret;
133 }
134 
135 void vfio_unblock_multiple_devices_migration(void)
136 {
137     if (!multiple_devices_migration_blocker ||
138         !vfio_multiple_devices_migration_is_supported()) {
139         return;
140     }
141 
142     migrate_del_blocker(&multiple_devices_migration_blocker);
143 }
144 
145 bool vfio_viommu_preset(VFIODevice *vbasedev)
146 {
147     return vbasedev->bcontainer->space->as != &address_space_memory;
148 }
149 
150 static void vfio_set_migration_error(int ret)
151 {
152     if (migration_is_setup_or_active()) {
153         migration_file_set_error(ret, NULL);
154     }
155 }
156 
157 bool vfio_device_state_is_running(VFIODevice *vbasedev)
158 {
159     VFIOMigration *migration = vbasedev->migration;
160 
161     return migration->device_state == VFIO_DEVICE_STATE_RUNNING ||
162            migration->device_state == VFIO_DEVICE_STATE_RUNNING_P2P;
163 }
164 
165 bool vfio_device_state_is_precopy(VFIODevice *vbasedev)
166 {
167     VFIOMigration *migration = vbasedev->migration;
168 
169     return migration->device_state == VFIO_DEVICE_STATE_PRE_COPY ||
170            migration->device_state == VFIO_DEVICE_STATE_PRE_COPY_P2P;
171 }
172 
173 static bool vfio_devices_all_dirty_tracking(VFIOContainerBase *bcontainer)
174 {
175     VFIODevice *vbasedev;
176 
177     if (!migration_is_active() && !migration_is_device()) {
178         return false;
179     }
180 
181     QLIST_FOREACH(vbasedev, &bcontainer->device_list, container_next) {
182         VFIOMigration *migration = vbasedev->migration;
183 
184         if (!migration) {
185             return false;
186         }
187 
188         if (vbasedev->pre_copy_dirty_page_tracking == ON_OFF_AUTO_OFF &&
189             (vfio_device_state_is_running(vbasedev) ||
190              vfio_device_state_is_precopy(vbasedev))) {
191             return false;
192         }
193     }
194     return true;
195 }
196 
197 bool vfio_devices_all_device_dirty_tracking(const VFIOContainerBase *bcontainer)
198 {
199     VFIODevice *vbasedev;
200 
201     QLIST_FOREACH(vbasedev, &bcontainer->device_list, container_next) {
202         if (!vbasedev->dirty_pages_supported) {
203             return false;
204         }
205     }
206 
207     return true;
208 }
209 
210 /*
211  * Check if all VFIO devices are running and migration is active, which is
212  * essentially equivalent to the migration being in pre-copy phase.
213  */
214 bool
215 vfio_devices_all_running_and_mig_active(const VFIOContainerBase *bcontainer)
216 {
217     VFIODevice *vbasedev;
218 
219     if (!migration_is_active()) {
220         return false;
221     }
222 
223     QLIST_FOREACH(vbasedev, &bcontainer->device_list, container_next) {
224         VFIOMigration *migration = vbasedev->migration;
225 
226         if (!migration) {
227             return false;
228         }
229 
230         if (vfio_device_state_is_running(vbasedev) ||
231             vfio_device_state_is_precopy(vbasedev)) {
232             continue;
233         } else {
234             return false;
235         }
236     }
237     return true;
238 }
239 
240 static bool vfio_listener_skipped_section(MemoryRegionSection *section)
241 {
242     return (!memory_region_is_ram(section->mr) &&
243             !memory_region_is_iommu(section->mr)) ||
244            memory_region_is_protected(section->mr) ||
245            /*
246             * Sizing an enabled 64-bit BAR can cause spurious mappings to
247             * addresses in the upper part of the 64-bit address space.  These
248             * are never accessed by the CPU and beyond the address width of
249             * some IOMMU hardware.  TODO: VFIO should tell us the IOMMU width.
250             */
251            section->offset_within_address_space & (1ULL << 63);
252 }
253 
254 /* Called with rcu_read_lock held.  */
255 static bool vfio_get_xlat_addr(IOMMUTLBEntry *iotlb, void **vaddr,
256                                ram_addr_t *ram_addr, bool *read_only,
257                                Error **errp)
258 {
259     bool ret, mr_has_discard_manager;
260 
261     ret = memory_get_xlat_addr(iotlb, vaddr, ram_addr, read_only,
262                                &mr_has_discard_manager, errp);
263     if (ret && mr_has_discard_manager) {
264         /*
265          * Malicious VMs might trigger discarding of IOMMU-mapped memory. The
266          * pages will remain pinned inside vfio until unmapped, resulting in a
267          * higher memory consumption than expected. If memory would get
268          * populated again later, there would be an inconsistency between pages
269          * pinned by vfio and pages seen by QEMU. This is the case until
270          * unmapped from the IOMMU (e.g., during device reset).
271          *
272          * With malicious guests, we really only care about pinning more memory
273          * than expected. RLIMIT_MEMLOCK set for the user/process can never be
274          * exceeded and can be used to mitigate this problem.
275          */
276         warn_report_once("Using vfio with vIOMMUs and coordinated discarding of"
277                          " RAM (e.g., virtio-mem) works, however, malicious"
278                          " guests can trigger pinning of more memory than"
279                          " intended via an IOMMU. It's possible to mitigate "
280                          " by setting/adjusting RLIMIT_MEMLOCK.");
281     }
282     return ret;
283 }
284 
285 static void vfio_iommu_map_notify(IOMMUNotifier *n, IOMMUTLBEntry *iotlb)
286 {
287     VFIOGuestIOMMU *giommu = container_of(n, VFIOGuestIOMMU, n);
288     VFIOContainerBase *bcontainer = giommu->bcontainer;
289     hwaddr iova = iotlb->iova + giommu->iommu_offset;
290     void *vaddr;
291     int ret;
292     Error *local_err = NULL;
293 
294     trace_vfio_iommu_map_notify(iotlb->perm == IOMMU_NONE ? "UNMAP" : "MAP",
295                                 iova, iova + iotlb->addr_mask);
296 
297     if (iotlb->target_as != &address_space_memory) {
298         error_report("Wrong target AS \"%s\", only system memory is allowed",
299                      iotlb->target_as->name ? iotlb->target_as->name : "none");
300         vfio_set_migration_error(-EINVAL);
301         return;
302     }
303 
304     rcu_read_lock();
305 
306     if ((iotlb->perm & IOMMU_RW) != IOMMU_NONE) {
307         bool read_only;
308 
309         if (!vfio_get_xlat_addr(iotlb, &vaddr, NULL, &read_only, &local_err)) {
310             error_report_err(local_err);
311             goto out;
312         }
313         /*
314          * vaddr is only valid until rcu_read_unlock(). But after
315          * vfio_dma_map has set up the mapping the pages will be
316          * pinned by the kernel. This makes sure that the RAM backend
317          * of vaddr will always be there, even if the memory object is
318          * destroyed and its backing memory munmap-ed.
319          */
320         ret = vfio_container_dma_map(bcontainer, iova,
321                                      iotlb->addr_mask + 1, vaddr,
322                                      read_only);
323         if (ret) {
324             error_report("vfio_container_dma_map(%p, 0x%"HWADDR_PRIx", "
325                          "0x%"HWADDR_PRIx", %p) = %d (%s)",
326                          bcontainer, iova,
327                          iotlb->addr_mask + 1, vaddr, ret, strerror(-ret));
328         }
329     } else {
330         ret = vfio_container_dma_unmap(bcontainer, iova,
331                                        iotlb->addr_mask + 1, iotlb);
332         if (ret) {
333             error_report("vfio_container_dma_unmap(%p, 0x%"HWADDR_PRIx", "
334                          "0x%"HWADDR_PRIx") = %d (%s)",
335                          bcontainer, iova,
336                          iotlb->addr_mask + 1, ret, strerror(-ret));
337             vfio_set_migration_error(ret);
338         }
339     }
340 out:
341     rcu_read_unlock();
342 }
343 
344 static void vfio_ram_discard_notify_discard(RamDiscardListener *rdl,
345                                             MemoryRegionSection *section)
346 {
347     VFIORamDiscardListener *vrdl = container_of(rdl, VFIORamDiscardListener,
348                                                 listener);
349     VFIOContainerBase *bcontainer = vrdl->bcontainer;
350     const hwaddr size = int128_get64(section->size);
351     const hwaddr iova = section->offset_within_address_space;
352     int ret;
353 
354     /* Unmap with a single call. */
355     ret = vfio_container_dma_unmap(bcontainer, iova, size , NULL);
356     if (ret) {
357         error_report("%s: vfio_container_dma_unmap() failed: %s", __func__,
358                      strerror(-ret));
359     }
360 }
361 
362 static int vfio_ram_discard_notify_populate(RamDiscardListener *rdl,
363                                             MemoryRegionSection *section)
364 {
365     VFIORamDiscardListener *vrdl = container_of(rdl, VFIORamDiscardListener,
366                                                 listener);
367     VFIOContainerBase *bcontainer = vrdl->bcontainer;
368     const hwaddr end = section->offset_within_region +
369                        int128_get64(section->size);
370     hwaddr start, next, iova;
371     void *vaddr;
372     int ret;
373 
374     /*
375      * Map in (aligned within memory region) minimum granularity, so we can
376      * unmap in minimum granularity later.
377      */
378     for (start = section->offset_within_region; start < end; start = next) {
379         next = ROUND_UP(start + 1, vrdl->granularity);
380         next = MIN(next, end);
381 
382         iova = start - section->offset_within_region +
383                section->offset_within_address_space;
384         vaddr = memory_region_get_ram_ptr(section->mr) + start;
385 
386         ret = vfio_container_dma_map(bcontainer, iova, next - start,
387                                      vaddr, section->readonly);
388         if (ret) {
389             /* Rollback */
390             vfio_ram_discard_notify_discard(rdl, section);
391             return ret;
392         }
393     }
394     return 0;
395 }
396 
397 static void vfio_register_ram_discard_listener(VFIOContainerBase *bcontainer,
398                                                MemoryRegionSection *section)
399 {
400     RamDiscardManager *rdm = memory_region_get_ram_discard_manager(section->mr);
401     VFIORamDiscardListener *vrdl;
402 
403     /* Ignore some corner cases not relevant in practice. */
404     g_assert(QEMU_IS_ALIGNED(section->offset_within_region, TARGET_PAGE_SIZE));
405     g_assert(QEMU_IS_ALIGNED(section->offset_within_address_space,
406                              TARGET_PAGE_SIZE));
407     g_assert(QEMU_IS_ALIGNED(int128_get64(section->size), TARGET_PAGE_SIZE));
408 
409     vrdl = g_new0(VFIORamDiscardListener, 1);
410     vrdl->bcontainer = bcontainer;
411     vrdl->mr = section->mr;
412     vrdl->offset_within_address_space = section->offset_within_address_space;
413     vrdl->size = int128_get64(section->size);
414     vrdl->granularity = ram_discard_manager_get_min_granularity(rdm,
415                                                                 section->mr);
416 
417     g_assert(vrdl->granularity && is_power_of_2(vrdl->granularity));
418     g_assert(bcontainer->pgsizes &&
419              vrdl->granularity >= 1ULL << ctz64(bcontainer->pgsizes));
420 
421     ram_discard_listener_init(&vrdl->listener,
422                               vfio_ram_discard_notify_populate,
423                               vfio_ram_discard_notify_discard, true);
424     ram_discard_manager_register_listener(rdm, &vrdl->listener, section);
425     QLIST_INSERT_HEAD(&bcontainer->vrdl_list, vrdl, next);
426 
427     /*
428      * Sanity-check if we have a theoretically problematic setup where we could
429      * exceed the maximum number of possible DMA mappings over time. We assume
430      * that each mapped section in the same address space as a RamDiscardManager
431      * section consumes exactly one DMA mapping, with the exception of
432      * RamDiscardManager sections; i.e., we don't expect to have gIOMMU sections
433      * in the same address space as RamDiscardManager sections.
434      *
435      * We assume that each section in the address space consumes one memslot.
436      * We take the number of KVM memory slots as a best guess for the maximum
437      * number of sections in the address space we could have over time,
438      * also consuming DMA mappings.
439      */
440     if (bcontainer->dma_max_mappings) {
441         unsigned int vrdl_count = 0, vrdl_mappings = 0, max_memslots = 512;
442 
443 #ifdef CONFIG_KVM
444         if (kvm_enabled()) {
445             max_memslots = kvm_get_max_memslots();
446         }
447 #endif
448 
449         QLIST_FOREACH(vrdl, &bcontainer->vrdl_list, next) {
450             hwaddr start, end;
451 
452             start = QEMU_ALIGN_DOWN(vrdl->offset_within_address_space,
453                                     vrdl->granularity);
454             end = ROUND_UP(vrdl->offset_within_address_space + vrdl->size,
455                            vrdl->granularity);
456             vrdl_mappings += (end - start) / vrdl->granularity;
457             vrdl_count++;
458         }
459 
460         if (vrdl_mappings + max_memslots - vrdl_count >
461             bcontainer->dma_max_mappings) {
462             warn_report("%s: possibly running out of DMA mappings. E.g., try"
463                         " increasing the 'block-size' of virtio-mem devies."
464                         " Maximum possible DMA mappings: %d, Maximum possible"
465                         " memslots: %d", __func__, bcontainer->dma_max_mappings,
466                         max_memslots);
467         }
468     }
469 }
470 
471 static void vfio_unregister_ram_discard_listener(VFIOContainerBase *bcontainer,
472                                                  MemoryRegionSection *section)
473 {
474     RamDiscardManager *rdm = memory_region_get_ram_discard_manager(section->mr);
475     VFIORamDiscardListener *vrdl = NULL;
476 
477     QLIST_FOREACH(vrdl, &bcontainer->vrdl_list, next) {
478         if (vrdl->mr == section->mr &&
479             vrdl->offset_within_address_space ==
480             section->offset_within_address_space) {
481             break;
482         }
483     }
484 
485     if (!vrdl) {
486         hw_error("vfio: Trying to unregister missing RAM discard listener");
487     }
488 
489     ram_discard_manager_unregister_listener(rdm, &vrdl->listener);
490     QLIST_REMOVE(vrdl, next);
491     g_free(vrdl);
492 }
493 
494 static bool vfio_known_safe_misalignment(MemoryRegionSection *section)
495 {
496     MemoryRegion *mr = section->mr;
497 
498     if (!TPM_IS_CRB(mr->owner)) {
499         return false;
500     }
501 
502     /* this is a known safe misaligned region, just trace for debug purpose */
503     trace_vfio_known_safe_misalignment(memory_region_name(mr),
504                                        section->offset_within_address_space,
505                                        section->offset_within_region,
506                                        qemu_real_host_page_size());
507     return true;
508 }
509 
510 static bool vfio_listener_valid_section(MemoryRegionSection *section,
511                                         const char *name)
512 {
513     if (vfio_listener_skipped_section(section)) {
514         trace_vfio_listener_region_skip(name,
515                 section->offset_within_address_space,
516                 section->offset_within_address_space +
517                 int128_get64(int128_sub(section->size, int128_one())));
518         return false;
519     }
520 
521     if (unlikely((section->offset_within_address_space &
522                   ~qemu_real_host_page_mask()) !=
523                  (section->offset_within_region & ~qemu_real_host_page_mask()))) {
524         if (!vfio_known_safe_misalignment(section)) {
525             error_report("%s received unaligned region %s iova=0x%"PRIx64
526                          " offset_within_region=0x%"PRIx64
527                          " qemu_real_host_page_size=0x%"PRIxPTR,
528                          __func__, memory_region_name(section->mr),
529                          section->offset_within_address_space,
530                          section->offset_within_region,
531                          qemu_real_host_page_size());
532         }
533         return false;
534     }
535 
536     return true;
537 }
538 
539 static bool vfio_get_section_iova_range(VFIOContainerBase *bcontainer,
540                                         MemoryRegionSection *section,
541                                         hwaddr *out_iova, hwaddr *out_end,
542                                         Int128 *out_llend)
543 {
544     Int128 llend;
545     hwaddr iova;
546 
547     iova = REAL_HOST_PAGE_ALIGN(section->offset_within_address_space);
548     llend = int128_make64(section->offset_within_address_space);
549     llend = int128_add(llend, section->size);
550     llend = int128_and(llend, int128_exts64(qemu_real_host_page_mask()));
551 
552     if (int128_ge(int128_make64(iova), llend)) {
553         return false;
554     }
555 
556     *out_iova = iova;
557     *out_end = int128_get64(int128_sub(llend, int128_one()));
558     if (out_llend) {
559         *out_llend = llend;
560     }
561     return true;
562 }
563 
564 static void vfio_listener_region_add(MemoryListener *listener,
565                                      MemoryRegionSection *section)
566 {
567     VFIOContainerBase *bcontainer = container_of(listener, VFIOContainerBase,
568                                                  listener);
569     hwaddr iova, end;
570     Int128 llend, llsize;
571     void *vaddr;
572     int ret;
573     Error *err = NULL;
574 
575     if (!vfio_listener_valid_section(section, "region_add")) {
576         return;
577     }
578 
579     if (!vfio_get_section_iova_range(bcontainer, section, &iova, &end,
580                                      &llend)) {
581         if (memory_region_is_ram_device(section->mr)) {
582             trace_vfio_listener_region_add_no_dma_map(
583                 memory_region_name(section->mr),
584                 section->offset_within_address_space,
585                 int128_getlo(section->size),
586                 qemu_real_host_page_size());
587         }
588         return;
589     }
590 
591     if (!vfio_container_add_section_window(bcontainer, section, &err)) {
592         goto fail;
593     }
594 
595     memory_region_ref(section->mr);
596 
597     if (memory_region_is_iommu(section->mr)) {
598         VFIOGuestIOMMU *giommu;
599         IOMMUMemoryRegion *iommu_mr = IOMMU_MEMORY_REGION(section->mr);
600         int iommu_idx;
601 
602         trace_vfio_listener_region_add_iommu(section->mr->name, iova, end);
603         /*
604          * FIXME: For VFIO iommu types which have KVM acceleration to
605          * avoid bouncing all map/unmaps through qemu this way, this
606          * would be the right place to wire that up (tell the KVM
607          * device emulation the VFIO iommu handles to use).
608          */
609         giommu = g_malloc0(sizeof(*giommu));
610         giommu->iommu_mr = iommu_mr;
611         giommu->iommu_offset = section->offset_within_address_space -
612                                section->offset_within_region;
613         giommu->bcontainer = bcontainer;
614         llend = int128_add(int128_make64(section->offset_within_region),
615                            section->size);
616         llend = int128_sub(llend, int128_one());
617         iommu_idx = memory_region_iommu_attrs_to_index(iommu_mr,
618                                                        MEMTXATTRS_UNSPECIFIED);
619         iommu_notifier_init(&giommu->n, vfio_iommu_map_notify,
620                             IOMMU_NOTIFIER_IOTLB_EVENTS,
621                             section->offset_within_region,
622                             int128_get64(llend),
623                             iommu_idx);
624 
625         ret = memory_region_register_iommu_notifier(section->mr, &giommu->n,
626                                                     &err);
627         if (ret) {
628             g_free(giommu);
629             goto fail;
630         }
631         QLIST_INSERT_HEAD(&bcontainer->giommu_list, giommu, giommu_next);
632         memory_region_iommu_replay(giommu->iommu_mr, &giommu->n);
633 
634         return;
635     }
636 
637     /* Here we assume that memory_region_is_ram(section->mr)==true */
638 
639     /*
640      * For RAM memory regions with a RamDiscardManager, we only want to map the
641      * actually populated parts - and update the mapping whenever we're notified
642      * about changes.
643      */
644     if (memory_region_has_ram_discard_manager(section->mr)) {
645         vfio_register_ram_discard_listener(bcontainer, section);
646         return;
647     }
648 
649     vaddr = memory_region_get_ram_ptr(section->mr) +
650             section->offset_within_region +
651             (iova - section->offset_within_address_space);
652 
653     trace_vfio_listener_region_add_ram(iova, end, vaddr);
654 
655     llsize = int128_sub(llend, int128_make64(iova));
656 
657     if (memory_region_is_ram_device(section->mr)) {
658         hwaddr pgmask = (1ULL << ctz64(bcontainer->pgsizes)) - 1;
659 
660         if ((iova & pgmask) || (int128_get64(llsize) & pgmask)) {
661             trace_vfio_listener_region_add_no_dma_map(
662                 memory_region_name(section->mr),
663                 section->offset_within_address_space,
664                 int128_getlo(section->size),
665                 pgmask + 1);
666             return;
667         }
668     }
669 
670     ret = vfio_container_dma_map(bcontainer, iova, int128_get64(llsize),
671                                  vaddr, section->readonly);
672     if (ret) {
673         error_setg(&err, "vfio_container_dma_map(%p, 0x%"HWADDR_PRIx", "
674                    "0x%"HWADDR_PRIx", %p) = %d (%s)",
675                    bcontainer, iova, int128_get64(llsize), vaddr, ret,
676                    strerror(-ret));
677         if (memory_region_is_ram_device(section->mr)) {
678             /* Allow unexpected mappings not to be fatal for RAM devices */
679             error_report_err(err);
680             return;
681         }
682         goto fail;
683     }
684 
685     return;
686 
687 fail:
688     if (memory_region_is_ram_device(section->mr)) {
689         error_reportf_err(err, "PCI p2p may not work: ");
690         return;
691     }
692     /*
693      * On the initfn path, store the first error in the container so we
694      * can gracefully fail.  Runtime, there's not much we can do other
695      * than throw a hardware error.
696      */
697     if (!bcontainer->initialized) {
698         if (!bcontainer->error) {
699             error_propagate_prepend(&bcontainer->error, err,
700                                     "Region %s: ",
701                                     memory_region_name(section->mr));
702         } else {
703             error_free(err);
704         }
705     } else {
706         error_report_err(err);
707         hw_error("vfio: DMA mapping failed, unable to continue");
708     }
709 }
710 
711 static void vfio_listener_region_del(MemoryListener *listener,
712                                      MemoryRegionSection *section)
713 {
714     VFIOContainerBase *bcontainer = container_of(listener, VFIOContainerBase,
715                                                  listener);
716     hwaddr iova, end;
717     Int128 llend, llsize;
718     int ret;
719     bool try_unmap = true;
720 
721     if (!vfio_listener_valid_section(section, "region_del")) {
722         return;
723     }
724 
725     if (memory_region_is_iommu(section->mr)) {
726         VFIOGuestIOMMU *giommu;
727 
728         trace_vfio_listener_region_del_iommu(section->mr->name);
729         QLIST_FOREACH(giommu, &bcontainer->giommu_list, giommu_next) {
730             if (MEMORY_REGION(giommu->iommu_mr) == section->mr &&
731                 giommu->n.start == section->offset_within_region) {
732                 memory_region_unregister_iommu_notifier(section->mr,
733                                                         &giommu->n);
734                 QLIST_REMOVE(giommu, giommu_next);
735                 g_free(giommu);
736                 break;
737             }
738         }
739 
740         /*
741          * FIXME: We assume the one big unmap below is adequate to
742          * remove any individual page mappings in the IOMMU which
743          * might have been copied into VFIO. This works for a page table
744          * based IOMMU where a big unmap flattens a large range of IO-PTEs.
745          * That may not be true for all IOMMU types.
746          */
747     }
748 
749     if (!vfio_get_section_iova_range(bcontainer, section, &iova, &end,
750                                      &llend)) {
751         return;
752     }
753 
754     llsize = int128_sub(llend, int128_make64(iova));
755 
756     trace_vfio_listener_region_del(iova, end);
757 
758     if (memory_region_is_ram_device(section->mr)) {
759         hwaddr pgmask;
760 
761         pgmask = (1ULL << ctz64(bcontainer->pgsizes)) - 1;
762         try_unmap = !((iova & pgmask) || (int128_get64(llsize) & pgmask));
763     } else if (memory_region_has_ram_discard_manager(section->mr)) {
764         vfio_unregister_ram_discard_listener(bcontainer, section);
765         /* Unregistering will trigger an unmap. */
766         try_unmap = false;
767     }
768 
769     if (try_unmap) {
770         if (int128_eq(llsize, int128_2_64())) {
771             /* The unmap ioctl doesn't accept a full 64-bit span. */
772             llsize = int128_rshift(llsize, 1);
773             ret = vfio_container_dma_unmap(bcontainer, iova,
774                                            int128_get64(llsize), NULL);
775             if (ret) {
776                 error_report("vfio_container_dma_unmap(%p, 0x%"HWADDR_PRIx", "
777                              "0x%"HWADDR_PRIx") = %d (%s)",
778                              bcontainer, iova, int128_get64(llsize), ret,
779                              strerror(-ret));
780             }
781             iova += int128_get64(llsize);
782         }
783         ret = vfio_container_dma_unmap(bcontainer, iova,
784                                        int128_get64(llsize), NULL);
785         if (ret) {
786             error_report("vfio_container_dma_unmap(%p, 0x%"HWADDR_PRIx", "
787                          "0x%"HWADDR_PRIx") = %d (%s)",
788                          bcontainer, iova, int128_get64(llsize), ret,
789                          strerror(-ret));
790         }
791     }
792 
793     memory_region_unref(section->mr);
794 
795     vfio_container_del_section_window(bcontainer, section);
796 }
797 
798 typedef struct VFIODirtyRanges {
799     hwaddr min32;
800     hwaddr max32;
801     hwaddr min64;
802     hwaddr max64;
803     hwaddr minpci64;
804     hwaddr maxpci64;
805 } VFIODirtyRanges;
806 
807 typedef struct VFIODirtyRangesListener {
808     VFIOContainerBase *bcontainer;
809     VFIODirtyRanges ranges;
810     MemoryListener listener;
811 } VFIODirtyRangesListener;
812 
813 static bool vfio_section_is_vfio_pci(MemoryRegionSection *section,
814                                      VFIOContainerBase *bcontainer)
815 {
816     VFIOPCIDevice *pcidev;
817     VFIODevice *vbasedev;
818     Object *owner;
819 
820     owner = memory_region_owner(section->mr);
821 
822     QLIST_FOREACH(vbasedev, &bcontainer->device_list, container_next) {
823         if (vbasedev->type != VFIO_DEVICE_TYPE_PCI) {
824             continue;
825         }
826         pcidev = container_of(vbasedev, VFIOPCIDevice, vbasedev);
827         if (OBJECT(pcidev) == owner) {
828             return true;
829         }
830     }
831 
832     return false;
833 }
834 
835 static void vfio_dirty_tracking_update_range(VFIODirtyRanges *range,
836                                              hwaddr iova, hwaddr end,
837                                              bool update_pci)
838 {
839     hwaddr *min, *max;
840 
841     /*
842      * The address space passed to the dirty tracker is reduced to three ranges:
843      * one for 32-bit DMA ranges, one for 64-bit DMA ranges and one for the
844      * PCI 64-bit hole.
845      *
846      * The underlying reports of dirty will query a sub-interval of each of
847      * these ranges.
848      *
849      * The purpose of the three range handling is to handle known cases of big
850      * holes in the address space, like the x86 AMD 1T hole, and firmware (like
851      * OVMF) which may relocate the pci-hole64 to the end of the address space.
852      * The latter would otherwise generate large ranges for tracking, stressing
853      * the limits of supported hardware. The pci-hole32 will always be below 4G
854      * (overlapping or not) so it doesn't need special handling and is part of
855      * the 32-bit range.
856      *
857      * The alternative would be an IOVATree but that has a much bigger runtime
858      * overhead and unnecessary complexity.
859      */
860     if (update_pci && iova >= UINT32_MAX) {
861         min = &range->minpci64;
862         max = &range->maxpci64;
863     } else {
864         min = (end <= UINT32_MAX) ? &range->min32 : &range->min64;
865         max = (end <= UINT32_MAX) ? &range->max32 : &range->max64;
866     }
867     if (*min > iova) {
868         *min = iova;
869     }
870     if (*max < end) {
871         *max = end;
872     }
873 
874     trace_vfio_device_dirty_tracking_update(iova, end, *min, *max);
875 }
876 
877 static void vfio_dirty_tracking_update(MemoryListener *listener,
878                                        MemoryRegionSection *section)
879 {
880     VFIODirtyRangesListener *dirty =
881         container_of(listener, VFIODirtyRangesListener, listener);
882     hwaddr iova, end;
883 
884     if (!vfio_listener_valid_section(section, "tracking_update") ||
885         !vfio_get_section_iova_range(dirty->bcontainer, section,
886                                      &iova, &end, NULL)) {
887         return;
888     }
889 
890     vfio_dirty_tracking_update_range(&dirty->ranges, iova, end,
891                       vfio_section_is_vfio_pci(section, dirty->bcontainer));
892 }
893 
894 static const MemoryListener vfio_dirty_tracking_listener = {
895     .name = "vfio-tracking",
896     .region_add = vfio_dirty_tracking_update,
897 };
898 
899 static void vfio_dirty_tracking_init(VFIOContainerBase *bcontainer,
900                                      VFIODirtyRanges *ranges)
901 {
902     VFIODirtyRangesListener dirty;
903 
904     memset(&dirty, 0, sizeof(dirty));
905     dirty.ranges.min32 = UINT32_MAX;
906     dirty.ranges.min64 = UINT64_MAX;
907     dirty.ranges.minpci64 = UINT64_MAX;
908     dirty.listener = vfio_dirty_tracking_listener;
909     dirty.bcontainer = bcontainer;
910 
911     memory_listener_register(&dirty.listener,
912                              bcontainer->space->as);
913 
914     *ranges = dirty.ranges;
915 
916     /*
917      * The memory listener is synchronous, and used to calculate the range
918      * to dirty tracking. Unregister it after we are done as we are not
919      * interested in any follow-up updates.
920      */
921     memory_listener_unregister(&dirty.listener);
922 }
923 
924 static void vfio_devices_dma_logging_stop(VFIOContainerBase *bcontainer)
925 {
926     uint64_t buf[DIV_ROUND_UP(sizeof(struct vfio_device_feature),
927                               sizeof(uint64_t))] = {};
928     struct vfio_device_feature *feature = (struct vfio_device_feature *)buf;
929     VFIODevice *vbasedev;
930 
931     feature->argsz = sizeof(buf);
932     feature->flags = VFIO_DEVICE_FEATURE_SET |
933                      VFIO_DEVICE_FEATURE_DMA_LOGGING_STOP;
934 
935     QLIST_FOREACH(vbasedev, &bcontainer->device_list, container_next) {
936         if (!vbasedev->dirty_tracking) {
937             continue;
938         }
939 
940         if (ioctl(vbasedev->fd, VFIO_DEVICE_FEATURE, feature)) {
941             warn_report("%s: Failed to stop DMA logging, err %d (%s)",
942                         vbasedev->name, -errno, strerror(errno));
943         }
944         vbasedev->dirty_tracking = false;
945     }
946 }
947 
948 static struct vfio_device_feature *
949 vfio_device_feature_dma_logging_start_create(VFIOContainerBase *bcontainer,
950                                              VFIODirtyRanges *tracking)
951 {
952     struct vfio_device_feature *feature;
953     size_t feature_size;
954     struct vfio_device_feature_dma_logging_control *control;
955     struct vfio_device_feature_dma_logging_range *ranges;
956 
957     feature_size = sizeof(struct vfio_device_feature) +
958                    sizeof(struct vfio_device_feature_dma_logging_control);
959     feature = g_try_malloc0(feature_size);
960     if (!feature) {
961         errno = ENOMEM;
962         return NULL;
963     }
964     feature->argsz = feature_size;
965     feature->flags = VFIO_DEVICE_FEATURE_SET |
966                      VFIO_DEVICE_FEATURE_DMA_LOGGING_START;
967 
968     control = (struct vfio_device_feature_dma_logging_control *)feature->data;
969     control->page_size = qemu_real_host_page_size();
970 
971     /*
972      * DMA logging uAPI guarantees to support at least a number of ranges that
973      * fits into a single host kernel base page.
974      */
975     control->num_ranges = !!tracking->max32 + !!tracking->max64 +
976         !!tracking->maxpci64;
977     ranges = g_try_new0(struct vfio_device_feature_dma_logging_range,
978                         control->num_ranges);
979     if (!ranges) {
980         g_free(feature);
981         errno = ENOMEM;
982 
983         return NULL;
984     }
985 
986     control->ranges = (uintptr_t)ranges;
987     if (tracking->max32) {
988         ranges->iova = tracking->min32;
989         ranges->length = (tracking->max32 - tracking->min32) + 1;
990         ranges++;
991     }
992     if (tracking->max64) {
993         ranges->iova = tracking->min64;
994         ranges->length = (tracking->max64 - tracking->min64) + 1;
995         ranges++;
996     }
997     if (tracking->maxpci64) {
998         ranges->iova = tracking->minpci64;
999         ranges->length = (tracking->maxpci64 - tracking->minpci64) + 1;
1000     }
1001 
1002     trace_vfio_device_dirty_tracking_start(control->num_ranges,
1003                                            tracking->min32, tracking->max32,
1004                                            tracking->min64, tracking->max64,
1005                                            tracking->minpci64, tracking->maxpci64);
1006 
1007     return feature;
1008 }
1009 
1010 static void vfio_device_feature_dma_logging_start_destroy(
1011     struct vfio_device_feature *feature)
1012 {
1013     struct vfio_device_feature_dma_logging_control *control =
1014         (struct vfio_device_feature_dma_logging_control *)feature->data;
1015     struct vfio_device_feature_dma_logging_range *ranges =
1016         (struct vfio_device_feature_dma_logging_range *)(uintptr_t)control->ranges;
1017 
1018     g_free(ranges);
1019     g_free(feature);
1020 }
1021 
1022 static bool vfio_devices_dma_logging_start(VFIOContainerBase *bcontainer,
1023                                           Error **errp)
1024 {
1025     struct vfio_device_feature *feature;
1026     VFIODirtyRanges ranges;
1027     VFIODevice *vbasedev;
1028     int ret = 0;
1029 
1030     vfio_dirty_tracking_init(bcontainer, &ranges);
1031     feature = vfio_device_feature_dma_logging_start_create(bcontainer,
1032                                                            &ranges);
1033     if (!feature) {
1034         error_setg_errno(errp, errno, "Failed to prepare DMA logging");
1035         return false;
1036     }
1037 
1038     QLIST_FOREACH(vbasedev, &bcontainer->device_list, container_next) {
1039         if (vbasedev->dirty_tracking) {
1040             continue;
1041         }
1042 
1043         ret = ioctl(vbasedev->fd, VFIO_DEVICE_FEATURE, feature);
1044         if (ret) {
1045             ret = -errno;
1046             error_setg_errno(errp, errno, "%s: Failed to start DMA logging",
1047                              vbasedev->name);
1048             goto out;
1049         }
1050         vbasedev->dirty_tracking = true;
1051     }
1052 
1053 out:
1054     if (ret) {
1055         vfio_devices_dma_logging_stop(bcontainer);
1056     }
1057 
1058     vfio_device_feature_dma_logging_start_destroy(feature);
1059 
1060     return ret == 0;
1061 }
1062 
1063 static bool vfio_listener_log_global_start(MemoryListener *listener,
1064                                            Error **errp)
1065 {
1066     ERRP_GUARD();
1067     VFIOContainerBase *bcontainer = container_of(listener, VFIOContainerBase,
1068                                                  listener);
1069     bool ret;
1070 
1071     if (vfio_devices_all_device_dirty_tracking(bcontainer)) {
1072         ret = vfio_devices_dma_logging_start(bcontainer, errp);
1073     } else {
1074         ret = vfio_container_set_dirty_page_tracking(bcontainer, true, errp) == 0;
1075     }
1076 
1077     if (!ret) {
1078         error_prepend(errp, "vfio: Could not start dirty page tracking - ");
1079     }
1080     return ret;
1081 }
1082 
1083 static void vfio_listener_log_global_stop(MemoryListener *listener)
1084 {
1085     VFIOContainerBase *bcontainer = container_of(listener, VFIOContainerBase,
1086                                                  listener);
1087     Error *local_err = NULL;
1088     int ret = 0;
1089 
1090     if (vfio_devices_all_device_dirty_tracking(bcontainer)) {
1091         vfio_devices_dma_logging_stop(bcontainer);
1092     } else {
1093         ret = vfio_container_set_dirty_page_tracking(bcontainer, false,
1094                                                      &local_err);
1095     }
1096 
1097     if (ret) {
1098         error_prepend(&local_err,
1099                       "vfio: Could not stop dirty page tracking - ");
1100         error_report_err(local_err);
1101         vfio_set_migration_error(ret);
1102     }
1103 }
1104 
1105 static int vfio_device_dma_logging_report(VFIODevice *vbasedev, hwaddr iova,
1106                                           hwaddr size, void *bitmap)
1107 {
1108     uint64_t buf[DIV_ROUND_UP(sizeof(struct vfio_device_feature) +
1109                         sizeof(struct vfio_device_feature_dma_logging_report),
1110                         sizeof(uint64_t))] = {};
1111     struct vfio_device_feature *feature = (struct vfio_device_feature *)buf;
1112     struct vfio_device_feature_dma_logging_report *report =
1113         (struct vfio_device_feature_dma_logging_report *)feature->data;
1114 
1115     report->iova = iova;
1116     report->length = size;
1117     report->page_size = qemu_real_host_page_size();
1118     report->bitmap = (uintptr_t)bitmap;
1119 
1120     feature->argsz = sizeof(buf);
1121     feature->flags = VFIO_DEVICE_FEATURE_GET |
1122                      VFIO_DEVICE_FEATURE_DMA_LOGGING_REPORT;
1123 
1124     if (ioctl(vbasedev->fd, VFIO_DEVICE_FEATURE, feature)) {
1125         return -errno;
1126     }
1127 
1128     return 0;
1129 }
1130 
1131 int vfio_devices_query_dirty_bitmap(const VFIOContainerBase *bcontainer,
1132                  VFIOBitmap *vbmap, hwaddr iova, hwaddr size, Error **errp)
1133 {
1134     VFIODevice *vbasedev;
1135     int ret;
1136 
1137     QLIST_FOREACH(vbasedev, &bcontainer->device_list, container_next) {
1138         ret = vfio_device_dma_logging_report(vbasedev, iova, size,
1139                                              vbmap->bitmap);
1140         if (ret) {
1141             error_setg_errno(errp, -ret,
1142                              "%s: Failed to get DMA logging report, iova: "
1143                              "0x%" HWADDR_PRIx ", size: 0x%" HWADDR_PRIx,
1144                              vbasedev->name, iova, size);
1145 
1146             return ret;
1147         }
1148     }
1149 
1150     return 0;
1151 }
1152 
1153 int vfio_get_dirty_bitmap(const VFIOContainerBase *bcontainer, uint64_t iova,
1154                           uint64_t size, ram_addr_t ram_addr, Error **errp)
1155 {
1156     bool all_device_dirty_tracking =
1157         vfio_devices_all_device_dirty_tracking(bcontainer);
1158     uint64_t dirty_pages;
1159     VFIOBitmap vbmap;
1160     int ret;
1161 
1162     if (!bcontainer->dirty_pages_supported && !all_device_dirty_tracking) {
1163         cpu_physical_memory_set_dirty_range(ram_addr, size,
1164                                             tcg_enabled() ? DIRTY_CLIENTS_ALL :
1165                                             DIRTY_CLIENTS_NOCODE);
1166         return 0;
1167     }
1168 
1169     ret = vfio_bitmap_alloc(&vbmap, size);
1170     if (ret) {
1171         error_setg_errno(errp, -ret,
1172                          "Failed to allocate dirty tracking bitmap");
1173         return ret;
1174     }
1175 
1176     if (all_device_dirty_tracking) {
1177         ret = vfio_devices_query_dirty_bitmap(bcontainer, &vbmap, iova, size,
1178                                               errp);
1179     } else {
1180         ret = vfio_container_query_dirty_bitmap(bcontainer, &vbmap, iova, size,
1181                                                 errp);
1182     }
1183 
1184     if (ret) {
1185         goto out;
1186     }
1187 
1188     dirty_pages = cpu_physical_memory_set_dirty_lebitmap(vbmap.bitmap, ram_addr,
1189                                                          vbmap.pages);
1190 
1191     trace_vfio_get_dirty_bitmap(iova, size, vbmap.size, ram_addr, dirty_pages);
1192 out:
1193     g_free(vbmap.bitmap);
1194 
1195     return ret;
1196 }
1197 
1198 typedef struct {
1199     IOMMUNotifier n;
1200     VFIOGuestIOMMU *giommu;
1201 } vfio_giommu_dirty_notifier;
1202 
1203 static void vfio_iommu_map_dirty_notify(IOMMUNotifier *n, IOMMUTLBEntry *iotlb)
1204 {
1205     vfio_giommu_dirty_notifier *gdn = container_of(n,
1206                                                 vfio_giommu_dirty_notifier, n);
1207     VFIOGuestIOMMU *giommu = gdn->giommu;
1208     VFIOContainerBase *bcontainer = giommu->bcontainer;
1209     hwaddr iova = iotlb->iova + giommu->iommu_offset;
1210     ram_addr_t translated_addr;
1211     Error *local_err = NULL;
1212     int ret = -EINVAL;
1213 
1214     trace_vfio_iommu_map_dirty_notify(iova, iova + iotlb->addr_mask);
1215 
1216     if (iotlb->target_as != &address_space_memory) {
1217         error_report("Wrong target AS \"%s\", only system memory is allowed",
1218                      iotlb->target_as->name ? iotlb->target_as->name : "none");
1219         goto out;
1220     }
1221 
1222     rcu_read_lock();
1223     if (!vfio_get_xlat_addr(iotlb, NULL, &translated_addr, NULL, &local_err)) {
1224         error_report_err(local_err);
1225         goto out_unlock;
1226     }
1227 
1228     ret = vfio_get_dirty_bitmap(bcontainer, iova, iotlb->addr_mask + 1,
1229                                 translated_addr, &local_err);
1230     if (ret) {
1231         error_prepend(&local_err,
1232                       "vfio_iommu_map_dirty_notify(%p, 0x%"HWADDR_PRIx", "
1233                       "0x%"HWADDR_PRIx") failed - ", bcontainer, iova,
1234                       iotlb->addr_mask + 1);
1235         error_report_err(local_err);
1236     }
1237 
1238 out_unlock:
1239     rcu_read_unlock();
1240 
1241 out:
1242     if (ret) {
1243         vfio_set_migration_error(ret);
1244     }
1245 }
1246 
1247 static int vfio_ram_discard_get_dirty_bitmap(MemoryRegionSection *section,
1248                                              void *opaque)
1249 {
1250     const hwaddr size = int128_get64(section->size);
1251     const hwaddr iova = section->offset_within_address_space;
1252     const ram_addr_t ram_addr = memory_region_get_ram_addr(section->mr) +
1253                                 section->offset_within_region;
1254     VFIORamDiscardListener *vrdl = opaque;
1255     Error *local_err = NULL;
1256     int ret;
1257 
1258     /*
1259      * Sync the whole mapped region (spanning multiple individual mappings)
1260      * in one go.
1261      */
1262     ret = vfio_get_dirty_bitmap(vrdl->bcontainer, iova, size, ram_addr,
1263                                 &local_err);
1264     if (ret) {
1265         error_report_err(local_err);
1266     }
1267     return ret;
1268 }
1269 
1270 static int
1271 vfio_sync_ram_discard_listener_dirty_bitmap(VFIOContainerBase *bcontainer,
1272                                             MemoryRegionSection *section)
1273 {
1274     RamDiscardManager *rdm = memory_region_get_ram_discard_manager(section->mr);
1275     VFIORamDiscardListener *vrdl = NULL;
1276 
1277     QLIST_FOREACH(vrdl, &bcontainer->vrdl_list, next) {
1278         if (vrdl->mr == section->mr &&
1279             vrdl->offset_within_address_space ==
1280             section->offset_within_address_space) {
1281             break;
1282         }
1283     }
1284 
1285     if (!vrdl) {
1286         hw_error("vfio: Trying to sync missing RAM discard listener");
1287     }
1288 
1289     /*
1290      * We only want/can synchronize the bitmap for actually mapped parts -
1291      * which correspond to populated parts. Replay all populated parts.
1292      */
1293     return ram_discard_manager_replay_populated(rdm, section,
1294                                               vfio_ram_discard_get_dirty_bitmap,
1295                                                 &vrdl);
1296 }
1297 
1298 static int vfio_sync_iommu_dirty_bitmap(VFIOContainerBase *bcontainer,
1299                                         MemoryRegionSection *section)
1300 {
1301     VFIOGuestIOMMU *giommu;
1302     bool found = false;
1303     Int128 llend;
1304     vfio_giommu_dirty_notifier gdn;
1305     int idx;
1306 
1307     QLIST_FOREACH(giommu, &bcontainer->giommu_list, giommu_next) {
1308         if (MEMORY_REGION(giommu->iommu_mr) == section->mr &&
1309             giommu->n.start == section->offset_within_region) {
1310             found = true;
1311             break;
1312         }
1313     }
1314 
1315     if (!found) {
1316         return 0;
1317     }
1318 
1319     gdn.giommu = giommu;
1320     idx = memory_region_iommu_attrs_to_index(giommu->iommu_mr,
1321                                              MEMTXATTRS_UNSPECIFIED);
1322 
1323     llend = int128_add(int128_make64(section->offset_within_region),
1324                        section->size);
1325     llend = int128_sub(llend, int128_one());
1326 
1327     iommu_notifier_init(&gdn.n, vfio_iommu_map_dirty_notify, IOMMU_NOTIFIER_MAP,
1328                         section->offset_within_region, int128_get64(llend),
1329                         idx);
1330     memory_region_iommu_replay(giommu->iommu_mr, &gdn.n);
1331 
1332     return 0;
1333 }
1334 
1335 static int vfio_sync_dirty_bitmap(VFIOContainerBase *bcontainer,
1336                                   MemoryRegionSection *section, Error **errp)
1337 {
1338     ram_addr_t ram_addr;
1339 
1340     if (memory_region_is_iommu(section->mr)) {
1341         return vfio_sync_iommu_dirty_bitmap(bcontainer, section);
1342     } else if (memory_region_has_ram_discard_manager(section->mr)) {
1343         int ret;
1344 
1345         ret = vfio_sync_ram_discard_listener_dirty_bitmap(bcontainer, section);
1346         if (ret) {
1347             error_setg(errp,
1348                        "Failed to sync dirty bitmap with RAM discard listener");
1349         }
1350         return ret;
1351     }
1352 
1353     ram_addr = memory_region_get_ram_addr(section->mr) +
1354                section->offset_within_region;
1355 
1356     return vfio_get_dirty_bitmap(bcontainer,
1357                    REAL_HOST_PAGE_ALIGN(section->offset_within_address_space),
1358                                  int128_get64(section->size), ram_addr, errp);
1359 }
1360 
1361 static void vfio_listener_log_sync(MemoryListener *listener,
1362         MemoryRegionSection *section)
1363 {
1364     VFIOContainerBase *bcontainer = container_of(listener, VFIOContainerBase,
1365                                                  listener);
1366     int ret;
1367     Error *local_err = NULL;
1368 
1369     if (vfio_listener_skipped_section(section)) {
1370         return;
1371     }
1372 
1373     if (vfio_devices_all_dirty_tracking(bcontainer)) {
1374         ret = vfio_sync_dirty_bitmap(bcontainer, section, &local_err);
1375         if (ret) {
1376             error_report_err(local_err);
1377             vfio_set_migration_error(ret);
1378         }
1379     }
1380 }
1381 
1382 const MemoryListener vfio_memory_listener = {
1383     .name = "vfio",
1384     .region_add = vfio_listener_region_add,
1385     .region_del = vfio_listener_region_del,
1386     .log_global_start = vfio_listener_log_global_start,
1387     .log_global_stop = vfio_listener_log_global_stop,
1388     .log_sync = vfio_listener_log_sync,
1389 };
1390 
1391 void vfio_reset_handler(void *opaque)
1392 {
1393     VFIODevice *vbasedev;
1394 
1395     QLIST_FOREACH(vbasedev, &vfio_device_list, global_next) {
1396         if (vbasedev->dev->realized) {
1397             vbasedev->ops->vfio_compute_needs_reset(vbasedev);
1398         }
1399     }
1400 
1401     QLIST_FOREACH(vbasedev, &vfio_device_list, global_next) {
1402         if (vbasedev->dev->realized && vbasedev->needs_reset) {
1403             vbasedev->ops->vfio_hot_reset_multi(vbasedev);
1404         }
1405     }
1406 }
1407 
1408 int vfio_kvm_device_add_fd(int fd, Error **errp)
1409 {
1410 #ifdef CONFIG_KVM
1411     struct kvm_device_attr attr = {
1412         .group = KVM_DEV_VFIO_FILE,
1413         .attr = KVM_DEV_VFIO_FILE_ADD,
1414         .addr = (uint64_t)(unsigned long)&fd,
1415     };
1416 
1417     if (!kvm_enabled()) {
1418         return 0;
1419     }
1420 
1421     if (vfio_kvm_device_fd < 0) {
1422         struct kvm_create_device cd = {
1423             .type = KVM_DEV_TYPE_VFIO,
1424         };
1425 
1426         if (kvm_vm_ioctl(kvm_state, KVM_CREATE_DEVICE, &cd)) {
1427             error_setg_errno(errp, errno, "Failed to create KVM VFIO device");
1428             return -errno;
1429         }
1430 
1431         vfio_kvm_device_fd = cd.fd;
1432     }
1433 
1434     if (ioctl(vfio_kvm_device_fd, KVM_SET_DEVICE_ATTR, &attr)) {
1435         error_setg_errno(errp, errno, "Failed to add fd %d to KVM VFIO device",
1436                          fd);
1437         return -errno;
1438     }
1439 #endif
1440     return 0;
1441 }
1442 
1443 int vfio_kvm_device_del_fd(int fd, Error **errp)
1444 {
1445 #ifdef CONFIG_KVM
1446     struct kvm_device_attr attr = {
1447         .group = KVM_DEV_VFIO_FILE,
1448         .attr = KVM_DEV_VFIO_FILE_DEL,
1449         .addr = (uint64_t)(unsigned long)&fd,
1450     };
1451 
1452     if (vfio_kvm_device_fd < 0) {
1453         error_setg(errp, "KVM VFIO device isn't created yet");
1454         return -EINVAL;
1455     }
1456 
1457     if (ioctl(vfio_kvm_device_fd, KVM_SET_DEVICE_ATTR, &attr)) {
1458         error_setg_errno(errp, errno,
1459                          "Failed to remove fd %d from KVM VFIO device", fd);
1460         return -errno;
1461     }
1462 #endif
1463     return 0;
1464 }
1465 
1466 VFIOAddressSpace *vfio_get_address_space(AddressSpace *as)
1467 {
1468     VFIOAddressSpace *space;
1469 
1470     QLIST_FOREACH(space, &vfio_address_spaces, list) {
1471         if (space->as == as) {
1472             return space;
1473         }
1474     }
1475 
1476     /* No suitable VFIOAddressSpace, create a new one */
1477     space = g_malloc0(sizeof(*space));
1478     space->as = as;
1479     QLIST_INIT(&space->containers);
1480 
1481     if (QLIST_EMPTY(&vfio_address_spaces)) {
1482         qemu_register_reset(vfio_reset_handler, NULL);
1483     }
1484 
1485     QLIST_INSERT_HEAD(&vfio_address_spaces, space, list);
1486 
1487     return space;
1488 }
1489 
1490 void vfio_put_address_space(VFIOAddressSpace *space)
1491 {
1492     if (!QLIST_EMPTY(&space->containers)) {
1493         return;
1494     }
1495 
1496     QLIST_REMOVE(space, list);
1497     g_free(space);
1498 
1499     if (QLIST_EMPTY(&vfio_address_spaces)) {
1500         qemu_unregister_reset(vfio_reset_handler, NULL);
1501     }
1502 }
1503 
1504 void vfio_address_space_insert(VFIOAddressSpace *space,
1505                                VFIOContainerBase *bcontainer)
1506 {
1507     QLIST_INSERT_HEAD(&space->containers, bcontainer, next);
1508     bcontainer->space = space;
1509 }
1510 
1511 struct vfio_device_info *vfio_get_device_info(int fd)
1512 {
1513     struct vfio_device_info *info;
1514     uint32_t argsz = sizeof(*info);
1515 
1516     info = g_malloc0(argsz);
1517 
1518 retry:
1519     info->argsz = argsz;
1520 
1521     if (ioctl(fd, VFIO_DEVICE_GET_INFO, info)) {
1522         g_free(info);
1523         return NULL;
1524     }
1525 
1526     if (info->argsz > argsz) {
1527         argsz = info->argsz;
1528         info = g_realloc(info, argsz);
1529         goto retry;
1530     }
1531 
1532     return info;
1533 }
1534 
1535 bool vfio_attach_device(char *name, VFIODevice *vbasedev,
1536                         AddressSpace *as, Error **errp)
1537 {
1538     const VFIOIOMMUClass *ops =
1539         VFIO_IOMMU_CLASS(object_class_by_name(TYPE_VFIO_IOMMU_LEGACY));
1540     HostIOMMUDevice *hiod;
1541 
1542     if (vbasedev->iommufd) {
1543         ops = VFIO_IOMMU_CLASS(object_class_by_name(TYPE_VFIO_IOMMU_IOMMUFD));
1544     }
1545 
1546     assert(ops);
1547 
1548     if (!ops->attach_device(name, vbasedev, as, errp)) {
1549         return false;
1550     }
1551 
1552     hiod = HOST_IOMMU_DEVICE(object_new(ops->hiod_typename));
1553     if (!HOST_IOMMU_DEVICE_GET_CLASS(hiod)->realize(hiod, vbasedev, errp)) {
1554         object_unref(hiod);
1555         ops->detach_device(vbasedev);
1556         return false;
1557     }
1558     vbasedev->hiod = hiod;
1559 
1560     return true;
1561 }
1562 
1563 void vfio_detach_device(VFIODevice *vbasedev)
1564 {
1565     if (!vbasedev->bcontainer) {
1566         return;
1567     }
1568     object_unref(vbasedev->hiod);
1569     VFIO_IOMMU_GET_CLASS(vbasedev->bcontainer)->detach_device(vbasedev);
1570 }
1571