xref: /openbmc/qemu/hw/vfio/common.c (revision 30b91677)
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 
vfio_mig_active(void)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  */
vfio_multiple_devices_migration_is_supported(void)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 
vfio_block_multiple_devices_migration(VFIODevice * vbasedev,Error ** errp)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 
vfio_unblock_multiple_devices_migration(void)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 
vfio_viommu_preset(VFIODevice * vbasedev)145 bool vfio_viommu_preset(VFIODevice *vbasedev)
146 {
147     return vbasedev->bcontainer->space->as != &address_space_memory;
148 }
149 
vfio_set_migration_error(int ret)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 
vfio_device_state_is_running(VFIODevice * vbasedev)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 
vfio_device_state_is_precopy(VFIODevice * vbasedev)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 
vfio_devices_all_dirty_tracking(VFIOContainerBase * bcontainer)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 
vfio_devices_all_device_dirty_tracking(const VFIOContainerBase * bcontainer)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->device_dirty_page_tracking == ON_OFF_AUTO_OFF) {
203             return false;
204         }
205         if (!vbasedev->dirty_pages_supported) {
206             return false;
207         }
208     }
209 
210     return true;
211 }
212 
213 /*
214  * Check if all VFIO devices are running and migration is active, which is
215  * essentially equivalent to the migration being in pre-copy phase.
216  */
217 bool
vfio_devices_all_running_and_mig_active(const VFIOContainerBase * bcontainer)218 vfio_devices_all_running_and_mig_active(const VFIOContainerBase *bcontainer)
219 {
220     VFIODevice *vbasedev;
221 
222     if (!migration_is_active()) {
223         return false;
224     }
225 
226     QLIST_FOREACH(vbasedev, &bcontainer->device_list, container_next) {
227         VFIOMigration *migration = vbasedev->migration;
228 
229         if (!migration) {
230             return false;
231         }
232 
233         if (vfio_device_state_is_running(vbasedev) ||
234             vfio_device_state_is_precopy(vbasedev)) {
235             continue;
236         } else {
237             return false;
238         }
239     }
240     return true;
241 }
242 
vfio_listener_skipped_section(MemoryRegionSection * section)243 static bool vfio_listener_skipped_section(MemoryRegionSection *section)
244 {
245     return (!memory_region_is_ram(section->mr) &&
246             !memory_region_is_iommu(section->mr)) ||
247            memory_region_is_protected(section->mr) ||
248            /*
249             * Sizing an enabled 64-bit BAR can cause spurious mappings to
250             * addresses in the upper part of the 64-bit address space.  These
251             * are never accessed by the CPU and beyond the address width of
252             * some IOMMU hardware.  TODO: VFIO should tell us the IOMMU width.
253             */
254            section->offset_within_address_space & (1ULL << 63);
255 }
256 
257 /* Called with rcu_read_lock held.  */
vfio_get_xlat_addr(IOMMUTLBEntry * iotlb,void ** vaddr,ram_addr_t * ram_addr,bool * read_only,Error ** errp)258 static bool vfio_get_xlat_addr(IOMMUTLBEntry *iotlb, void **vaddr,
259                                ram_addr_t *ram_addr, bool *read_only,
260                                Error **errp)
261 {
262     bool ret, mr_has_discard_manager;
263 
264     ret = memory_get_xlat_addr(iotlb, vaddr, ram_addr, read_only,
265                                &mr_has_discard_manager, errp);
266     if (ret && mr_has_discard_manager) {
267         /*
268          * Malicious VMs might trigger discarding of IOMMU-mapped memory. The
269          * pages will remain pinned inside vfio until unmapped, resulting in a
270          * higher memory consumption than expected. If memory would get
271          * populated again later, there would be an inconsistency between pages
272          * pinned by vfio and pages seen by QEMU. This is the case until
273          * unmapped from the IOMMU (e.g., during device reset).
274          *
275          * With malicious guests, we really only care about pinning more memory
276          * than expected. RLIMIT_MEMLOCK set for the user/process can never be
277          * exceeded and can be used to mitigate this problem.
278          */
279         warn_report_once("Using vfio with vIOMMUs and coordinated discarding of"
280                          " RAM (e.g., virtio-mem) works, however, malicious"
281                          " guests can trigger pinning of more memory than"
282                          " intended via an IOMMU. It's possible to mitigate "
283                          " by setting/adjusting RLIMIT_MEMLOCK.");
284     }
285     return ret;
286 }
287 
vfio_iommu_map_notify(IOMMUNotifier * n,IOMMUTLBEntry * iotlb)288 static void vfio_iommu_map_notify(IOMMUNotifier *n, IOMMUTLBEntry *iotlb)
289 {
290     VFIOGuestIOMMU *giommu = container_of(n, VFIOGuestIOMMU, n);
291     VFIOContainerBase *bcontainer = giommu->bcontainer;
292     hwaddr iova = iotlb->iova + giommu->iommu_offset;
293     void *vaddr;
294     int ret;
295     Error *local_err = NULL;
296 
297     trace_vfio_iommu_map_notify(iotlb->perm == IOMMU_NONE ? "UNMAP" : "MAP",
298                                 iova, iova + iotlb->addr_mask);
299 
300     if (iotlb->target_as != &address_space_memory) {
301         error_report("Wrong target AS \"%s\", only system memory is allowed",
302                      iotlb->target_as->name ? iotlb->target_as->name : "none");
303         vfio_set_migration_error(-EINVAL);
304         return;
305     }
306 
307     rcu_read_lock();
308 
309     if ((iotlb->perm & IOMMU_RW) != IOMMU_NONE) {
310         bool read_only;
311 
312         if (!vfio_get_xlat_addr(iotlb, &vaddr, NULL, &read_only, &local_err)) {
313             error_report_err(local_err);
314             goto out;
315         }
316         /*
317          * vaddr is only valid until rcu_read_unlock(). But after
318          * vfio_dma_map has set up the mapping the pages will be
319          * pinned by the kernel. This makes sure that the RAM backend
320          * of vaddr will always be there, even if the memory object is
321          * destroyed and its backing memory munmap-ed.
322          */
323         ret = vfio_container_dma_map(bcontainer, iova,
324                                      iotlb->addr_mask + 1, vaddr,
325                                      read_only);
326         if (ret) {
327             error_report("vfio_container_dma_map(%p, 0x%"HWADDR_PRIx", "
328                          "0x%"HWADDR_PRIx", %p) = %d (%s)",
329                          bcontainer, iova,
330                          iotlb->addr_mask + 1, vaddr, ret, strerror(-ret));
331         }
332     } else {
333         ret = vfio_container_dma_unmap(bcontainer, iova,
334                                        iotlb->addr_mask + 1, iotlb);
335         if (ret) {
336             error_report("vfio_container_dma_unmap(%p, 0x%"HWADDR_PRIx", "
337                          "0x%"HWADDR_PRIx") = %d (%s)",
338                          bcontainer, iova,
339                          iotlb->addr_mask + 1, ret, strerror(-ret));
340             vfio_set_migration_error(ret);
341         }
342     }
343 out:
344     rcu_read_unlock();
345 }
346 
vfio_ram_discard_notify_discard(RamDiscardListener * rdl,MemoryRegionSection * section)347 static void vfio_ram_discard_notify_discard(RamDiscardListener *rdl,
348                                             MemoryRegionSection *section)
349 {
350     VFIORamDiscardListener *vrdl = container_of(rdl, VFIORamDiscardListener,
351                                                 listener);
352     VFIOContainerBase *bcontainer = vrdl->bcontainer;
353     const hwaddr size = int128_get64(section->size);
354     const hwaddr iova = section->offset_within_address_space;
355     int ret;
356 
357     /* Unmap with a single call. */
358     ret = vfio_container_dma_unmap(bcontainer, iova, size , NULL);
359     if (ret) {
360         error_report("%s: vfio_container_dma_unmap() failed: %s", __func__,
361                      strerror(-ret));
362     }
363 }
364 
vfio_ram_discard_notify_populate(RamDiscardListener * rdl,MemoryRegionSection * section)365 static int vfio_ram_discard_notify_populate(RamDiscardListener *rdl,
366                                             MemoryRegionSection *section)
367 {
368     VFIORamDiscardListener *vrdl = container_of(rdl, VFIORamDiscardListener,
369                                                 listener);
370     VFIOContainerBase *bcontainer = vrdl->bcontainer;
371     const hwaddr end = section->offset_within_region +
372                        int128_get64(section->size);
373     hwaddr start, next, iova;
374     void *vaddr;
375     int ret;
376 
377     /*
378      * Map in (aligned within memory region) minimum granularity, so we can
379      * unmap in minimum granularity later.
380      */
381     for (start = section->offset_within_region; start < end; start = next) {
382         next = ROUND_UP(start + 1, vrdl->granularity);
383         next = MIN(next, end);
384 
385         iova = start - section->offset_within_region +
386                section->offset_within_address_space;
387         vaddr = memory_region_get_ram_ptr(section->mr) + start;
388 
389         ret = vfio_container_dma_map(bcontainer, iova, next - start,
390                                      vaddr, section->readonly);
391         if (ret) {
392             /* Rollback */
393             vfio_ram_discard_notify_discard(rdl, section);
394             return ret;
395         }
396     }
397     return 0;
398 }
399 
vfio_register_ram_discard_listener(VFIOContainerBase * bcontainer,MemoryRegionSection * section)400 static void vfio_register_ram_discard_listener(VFIOContainerBase *bcontainer,
401                                                MemoryRegionSection *section)
402 {
403     RamDiscardManager *rdm = memory_region_get_ram_discard_manager(section->mr);
404     VFIORamDiscardListener *vrdl;
405 
406     /* Ignore some corner cases not relevant in practice. */
407     g_assert(QEMU_IS_ALIGNED(section->offset_within_region, TARGET_PAGE_SIZE));
408     g_assert(QEMU_IS_ALIGNED(section->offset_within_address_space,
409                              TARGET_PAGE_SIZE));
410     g_assert(QEMU_IS_ALIGNED(int128_get64(section->size), TARGET_PAGE_SIZE));
411 
412     vrdl = g_new0(VFIORamDiscardListener, 1);
413     vrdl->bcontainer = bcontainer;
414     vrdl->mr = section->mr;
415     vrdl->offset_within_address_space = section->offset_within_address_space;
416     vrdl->size = int128_get64(section->size);
417     vrdl->granularity = ram_discard_manager_get_min_granularity(rdm,
418                                                                 section->mr);
419 
420     g_assert(vrdl->granularity && is_power_of_2(vrdl->granularity));
421     g_assert(bcontainer->pgsizes &&
422              vrdl->granularity >= 1ULL << ctz64(bcontainer->pgsizes));
423 
424     ram_discard_listener_init(&vrdl->listener,
425                               vfio_ram_discard_notify_populate,
426                               vfio_ram_discard_notify_discard, true);
427     ram_discard_manager_register_listener(rdm, &vrdl->listener, section);
428     QLIST_INSERT_HEAD(&bcontainer->vrdl_list, vrdl, next);
429 
430     /*
431      * Sanity-check if we have a theoretically problematic setup where we could
432      * exceed the maximum number of possible DMA mappings over time. We assume
433      * that each mapped section in the same address space as a RamDiscardManager
434      * section consumes exactly one DMA mapping, with the exception of
435      * RamDiscardManager sections; i.e., we don't expect to have gIOMMU sections
436      * in the same address space as RamDiscardManager sections.
437      *
438      * We assume that each section in the address space consumes one memslot.
439      * We take the number of KVM memory slots as a best guess for the maximum
440      * number of sections in the address space we could have over time,
441      * also consuming DMA mappings.
442      */
443     if (bcontainer->dma_max_mappings) {
444         unsigned int vrdl_count = 0, vrdl_mappings = 0, max_memslots = 512;
445 
446 #ifdef CONFIG_KVM
447         if (kvm_enabled()) {
448             max_memslots = kvm_get_max_memslots();
449         }
450 #endif
451 
452         QLIST_FOREACH(vrdl, &bcontainer->vrdl_list, next) {
453             hwaddr start, end;
454 
455             start = QEMU_ALIGN_DOWN(vrdl->offset_within_address_space,
456                                     vrdl->granularity);
457             end = ROUND_UP(vrdl->offset_within_address_space + vrdl->size,
458                            vrdl->granularity);
459             vrdl_mappings += (end - start) / vrdl->granularity;
460             vrdl_count++;
461         }
462 
463         if (vrdl_mappings + max_memslots - vrdl_count >
464             bcontainer->dma_max_mappings) {
465             warn_report("%s: possibly running out of DMA mappings. E.g., try"
466                         " increasing the 'block-size' of virtio-mem devies."
467                         " Maximum possible DMA mappings: %d, Maximum possible"
468                         " memslots: %d", __func__, bcontainer->dma_max_mappings,
469                         max_memslots);
470         }
471     }
472 }
473 
vfio_unregister_ram_discard_listener(VFIOContainerBase * bcontainer,MemoryRegionSection * section)474 static void vfio_unregister_ram_discard_listener(VFIOContainerBase *bcontainer,
475                                                  MemoryRegionSection *section)
476 {
477     RamDiscardManager *rdm = memory_region_get_ram_discard_manager(section->mr);
478     VFIORamDiscardListener *vrdl = NULL;
479 
480     QLIST_FOREACH(vrdl, &bcontainer->vrdl_list, next) {
481         if (vrdl->mr == section->mr &&
482             vrdl->offset_within_address_space ==
483             section->offset_within_address_space) {
484             break;
485         }
486     }
487 
488     if (!vrdl) {
489         hw_error("vfio: Trying to unregister missing RAM discard listener");
490     }
491 
492     ram_discard_manager_unregister_listener(rdm, &vrdl->listener);
493     QLIST_REMOVE(vrdl, next);
494     g_free(vrdl);
495 }
496 
vfio_known_safe_misalignment(MemoryRegionSection * section)497 static bool vfio_known_safe_misalignment(MemoryRegionSection *section)
498 {
499     MemoryRegion *mr = section->mr;
500 
501     if (!TPM_IS_CRB(mr->owner)) {
502         return false;
503     }
504 
505     /* this is a known safe misaligned region, just trace for debug purpose */
506     trace_vfio_known_safe_misalignment(memory_region_name(mr),
507                                        section->offset_within_address_space,
508                                        section->offset_within_region,
509                                        qemu_real_host_page_size());
510     return true;
511 }
512 
vfio_listener_valid_section(MemoryRegionSection * section,const char * name)513 static bool vfio_listener_valid_section(MemoryRegionSection *section,
514                                         const char *name)
515 {
516     if (vfio_listener_skipped_section(section)) {
517         trace_vfio_listener_region_skip(name,
518                 section->offset_within_address_space,
519                 section->offset_within_address_space +
520                 int128_get64(int128_sub(section->size, int128_one())));
521         return false;
522     }
523 
524     if (unlikely((section->offset_within_address_space &
525                   ~qemu_real_host_page_mask()) !=
526                  (section->offset_within_region & ~qemu_real_host_page_mask()))) {
527         if (!vfio_known_safe_misalignment(section)) {
528             error_report("%s received unaligned region %s iova=0x%"PRIx64
529                          " offset_within_region=0x%"PRIx64
530                          " qemu_real_host_page_size=0x%"PRIxPTR,
531                          __func__, memory_region_name(section->mr),
532                          section->offset_within_address_space,
533                          section->offset_within_region,
534                          qemu_real_host_page_size());
535         }
536         return false;
537     }
538 
539     return true;
540 }
541 
vfio_get_section_iova_range(VFIOContainerBase * bcontainer,MemoryRegionSection * section,hwaddr * out_iova,hwaddr * out_end,Int128 * out_llend)542 static bool vfio_get_section_iova_range(VFIOContainerBase *bcontainer,
543                                         MemoryRegionSection *section,
544                                         hwaddr *out_iova, hwaddr *out_end,
545                                         Int128 *out_llend)
546 {
547     Int128 llend;
548     hwaddr iova;
549 
550     iova = REAL_HOST_PAGE_ALIGN(section->offset_within_address_space);
551     llend = int128_make64(section->offset_within_address_space);
552     llend = int128_add(llend, section->size);
553     llend = int128_and(llend, int128_exts64(qemu_real_host_page_mask()));
554 
555     if (int128_ge(int128_make64(iova), llend)) {
556         return false;
557     }
558 
559     *out_iova = iova;
560     *out_end = int128_get64(int128_sub(llend, int128_one()));
561     if (out_llend) {
562         *out_llend = llend;
563     }
564     return true;
565 }
566 
vfio_listener_region_add(MemoryListener * listener,MemoryRegionSection * section)567 static void vfio_listener_region_add(MemoryListener *listener,
568                                      MemoryRegionSection *section)
569 {
570     VFIOContainerBase *bcontainer = container_of(listener, VFIOContainerBase,
571                                                  listener);
572     hwaddr iova, end;
573     Int128 llend, llsize;
574     void *vaddr;
575     int ret;
576     Error *err = NULL;
577 
578     if (!vfio_listener_valid_section(section, "region_add")) {
579         return;
580     }
581 
582     if (!vfio_get_section_iova_range(bcontainer, section, &iova, &end,
583                                      &llend)) {
584         if (memory_region_is_ram_device(section->mr)) {
585             trace_vfio_listener_region_add_no_dma_map(
586                 memory_region_name(section->mr),
587                 section->offset_within_address_space,
588                 int128_getlo(section->size),
589                 qemu_real_host_page_size());
590         }
591         return;
592     }
593 
594     if (!vfio_container_add_section_window(bcontainer, section, &err)) {
595         goto fail;
596     }
597 
598     memory_region_ref(section->mr);
599 
600     if (memory_region_is_iommu(section->mr)) {
601         VFIOGuestIOMMU *giommu;
602         IOMMUMemoryRegion *iommu_mr = IOMMU_MEMORY_REGION(section->mr);
603         int iommu_idx;
604 
605         trace_vfio_listener_region_add_iommu(section->mr->name, iova, end);
606         /*
607          * FIXME: For VFIO iommu types which have KVM acceleration to
608          * avoid bouncing all map/unmaps through qemu this way, this
609          * would be the right place to wire that up (tell the KVM
610          * device emulation the VFIO iommu handles to use).
611          */
612         giommu = g_malloc0(sizeof(*giommu));
613         giommu->iommu_mr = iommu_mr;
614         giommu->iommu_offset = section->offset_within_address_space -
615                                section->offset_within_region;
616         giommu->bcontainer = bcontainer;
617         llend = int128_add(int128_make64(section->offset_within_region),
618                            section->size);
619         llend = int128_sub(llend, int128_one());
620         iommu_idx = memory_region_iommu_attrs_to_index(iommu_mr,
621                                                        MEMTXATTRS_UNSPECIFIED);
622         iommu_notifier_init(&giommu->n, vfio_iommu_map_notify,
623                             IOMMU_NOTIFIER_IOTLB_EVENTS,
624                             section->offset_within_region,
625                             int128_get64(llend),
626                             iommu_idx);
627 
628         ret = memory_region_register_iommu_notifier(section->mr, &giommu->n,
629                                                     &err);
630         if (ret) {
631             g_free(giommu);
632             goto fail;
633         }
634         QLIST_INSERT_HEAD(&bcontainer->giommu_list, giommu, giommu_next);
635         memory_region_iommu_replay(giommu->iommu_mr, &giommu->n);
636 
637         return;
638     }
639 
640     /* Here we assume that memory_region_is_ram(section->mr)==true */
641 
642     /*
643      * For RAM memory regions with a RamDiscardManager, we only want to map the
644      * actually populated parts - and update the mapping whenever we're notified
645      * about changes.
646      */
647     if (memory_region_has_ram_discard_manager(section->mr)) {
648         vfio_register_ram_discard_listener(bcontainer, section);
649         return;
650     }
651 
652     vaddr = memory_region_get_ram_ptr(section->mr) +
653             section->offset_within_region +
654             (iova - section->offset_within_address_space);
655 
656     trace_vfio_listener_region_add_ram(iova, end, vaddr);
657 
658     llsize = int128_sub(llend, int128_make64(iova));
659 
660     if (memory_region_is_ram_device(section->mr)) {
661         hwaddr pgmask = (1ULL << ctz64(bcontainer->pgsizes)) - 1;
662 
663         if ((iova & pgmask) || (int128_get64(llsize) & pgmask)) {
664             trace_vfio_listener_region_add_no_dma_map(
665                 memory_region_name(section->mr),
666                 section->offset_within_address_space,
667                 int128_getlo(section->size),
668                 pgmask + 1);
669             return;
670         }
671     }
672 
673     ret = vfio_container_dma_map(bcontainer, iova, int128_get64(llsize),
674                                  vaddr, section->readonly);
675     if (ret) {
676         error_setg(&err, "vfio_container_dma_map(%p, 0x%"HWADDR_PRIx", "
677                    "0x%"HWADDR_PRIx", %p) = %d (%s)",
678                    bcontainer, iova, int128_get64(llsize), vaddr, ret,
679                    strerror(-ret));
680         if (memory_region_is_ram_device(section->mr)) {
681             /* Allow unexpected mappings not to be fatal for RAM devices */
682             error_report_err(err);
683             return;
684         }
685         goto fail;
686     }
687 
688     return;
689 
690 fail:
691     if (memory_region_is_ram_device(section->mr)) {
692         error_reportf_err(err, "PCI p2p may not work: ");
693         return;
694     }
695     /*
696      * On the initfn path, store the first error in the container so we
697      * can gracefully fail.  Runtime, there's not much we can do other
698      * than throw a hardware error.
699      */
700     if (!bcontainer->initialized) {
701         if (!bcontainer->error) {
702             error_propagate_prepend(&bcontainer->error, err,
703                                     "Region %s: ",
704                                     memory_region_name(section->mr));
705         } else {
706             error_free(err);
707         }
708     } else {
709         error_report_err(err);
710         hw_error("vfio: DMA mapping failed, unable to continue");
711     }
712 }
713 
vfio_listener_region_del(MemoryListener * listener,MemoryRegionSection * section)714 static void vfio_listener_region_del(MemoryListener *listener,
715                                      MemoryRegionSection *section)
716 {
717     VFIOContainerBase *bcontainer = container_of(listener, VFIOContainerBase,
718                                                  listener);
719     hwaddr iova, end;
720     Int128 llend, llsize;
721     int ret;
722     bool try_unmap = true;
723 
724     if (!vfio_listener_valid_section(section, "region_del")) {
725         return;
726     }
727 
728     if (memory_region_is_iommu(section->mr)) {
729         VFIOGuestIOMMU *giommu;
730 
731         trace_vfio_listener_region_del_iommu(section->mr->name);
732         QLIST_FOREACH(giommu, &bcontainer->giommu_list, giommu_next) {
733             if (MEMORY_REGION(giommu->iommu_mr) == section->mr &&
734                 giommu->n.start == section->offset_within_region) {
735                 memory_region_unregister_iommu_notifier(section->mr,
736                                                         &giommu->n);
737                 QLIST_REMOVE(giommu, giommu_next);
738                 g_free(giommu);
739                 break;
740             }
741         }
742 
743         /*
744          * FIXME: We assume the one big unmap below is adequate to
745          * remove any individual page mappings in the IOMMU which
746          * might have been copied into VFIO. This works for a page table
747          * based IOMMU where a big unmap flattens a large range of IO-PTEs.
748          * That may not be true for all IOMMU types.
749          */
750     }
751 
752     if (!vfio_get_section_iova_range(bcontainer, section, &iova, &end,
753                                      &llend)) {
754         return;
755     }
756 
757     llsize = int128_sub(llend, int128_make64(iova));
758 
759     trace_vfio_listener_region_del(iova, end);
760 
761     if (memory_region_is_ram_device(section->mr)) {
762         hwaddr pgmask;
763 
764         pgmask = (1ULL << ctz64(bcontainer->pgsizes)) - 1;
765         try_unmap = !((iova & pgmask) || (int128_get64(llsize) & pgmask));
766     } else if (memory_region_has_ram_discard_manager(section->mr)) {
767         vfio_unregister_ram_discard_listener(bcontainer, section);
768         /* Unregistering will trigger an unmap. */
769         try_unmap = false;
770     }
771 
772     if (try_unmap) {
773         if (int128_eq(llsize, int128_2_64())) {
774             /* The unmap ioctl doesn't accept a full 64-bit span. */
775             llsize = int128_rshift(llsize, 1);
776             ret = vfio_container_dma_unmap(bcontainer, iova,
777                                            int128_get64(llsize), NULL);
778             if (ret) {
779                 error_report("vfio_container_dma_unmap(%p, 0x%"HWADDR_PRIx", "
780                              "0x%"HWADDR_PRIx") = %d (%s)",
781                              bcontainer, iova, int128_get64(llsize), ret,
782                              strerror(-ret));
783             }
784             iova += int128_get64(llsize);
785         }
786         ret = vfio_container_dma_unmap(bcontainer, iova,
787                                        int128_get64(llsize), NULL);
788         if (ret) {
789             error_report("vfio_container_dma_unmap(%p, 0x%"HWADDR_PRIx", "
790                          "0x%"HWADDR_PRIx") = %d (%s)",
791                          bcontainer, iova, int128_get64(llsize), ret,
792                          strerror(-ret));
793         }
794     }
795 
796     memory_region_unref(section->mr);
797 
798     vfio_container_del_section_window(bcontainer, section);
799 }
800 
801 typedef struct VFIODirtyRanges {
802     hwaddr min32;
803     hwaddr max32;
804     hwaddr min64;
805     hwaddr max64;
806     hwaddr minpci64;
807     hwaddr maxpci64;
808 } VFIODirtyRanges;
809 
810 typedef struct VFIODirtyRangesListener {
811     VFIOContainerBase *bcontainer;
812     VFIODirtyRanges ranges;
813     MemoryListener listener;
814 } VFIODirtyRangesListener;
815 
vfio_section_is_vfio_pci(MemoryRegionSection * section,VFIOContainerBase * bcontainer)816 static bool vfio_section_is_vfio_pci(MemoryRegionSection *section,
817                                      VFIOContainerBase *bcontainer)
818 {
819     VFIOPCIDevice *pcidev;
820     VFIODevice *vbasedev;
821     Object *owner;
822 
823     owner = memory_region_owner(section->mr);
824 
825     QLIST_FOREACH(vbasedev, &bcontainer->device_list, container_next) {
826         if (vbasedev->type != VFIO_DEVICE_TYPE_PCI) {
827             continue;
828         }
829         pcidev = container_of(vbasedev, VFIOPCIDevice, vbasedev);
830         if (OBJECT(pcidev) == owner) {
831             return true;
832         }
833     }
834 
835     return false;
836 }
837 
vfio_dirty_tracking_update_range(VFIODirtyRanges * range,hwaddr iova,hwaddr end,bool update_pci)838 static void vfio_dirty_tracking_update_range(VFIODirtyRanges *range,
839                                              hwaddr iova, hwaddr end,
840                                              bool update_pci)
841 {
842     hwaddr *min, *max;
843 
844     /*
845      * The address space passed to the dirty tracker is reduced to three ranges:
846      * one for 32-bit DMA ranges, one for 64-bit DMA ranges and one for the
847      * PCI 64-bit hole.
848      *
849      * The underlying reports of dirty will query a sub-interval of each of
850      * these ranges.
851      *
852      * The purpose of the three range handling is to handle known cases of big
853      * holes in the address space, like the x86 AMD 1T hole, and firmware (like
854      * OVMF) which may relocate the pci-hole64 to the end of the address space.
855      * The latter would otherwise generate large ranges for tracking, stressing
856      * the limits of supported hardware. The pci-hole32 will always be below 4G
857      * (overlapping or not) so it doesn't need special handling and is part of
858      * the 32-bit range.
859      *
860      * The alternative would be an IOVATree but that has a much bigger runtime
861      * overhead and unnecessary complexity.
862      */
863     if (update_pci && iova >= UINT32_MAX) {
864         min = &range->minpci64;
865         max = &range->maxpci64;
866     } else {
867         min = (end <= UINT32_MAX) ? &range->min32 : &range->min64;
868         max = (end <= UINT32_MAX) ? &range->max32 : &range->max64;
869     }
870     if (*min > iova) {
871         *min = iova;
872     }
873     if (*max < end) {
874         *max = end;
875     }
876 
877     trace_vfio_device_dirty_tracking_update(iova, end, *min, *max);
878 }
879 
vfio_dirty_tracking_update(MemoryListener * listener,MemoryRegionSection * section)880 static void vfio_dirty_tracking_update(MemoryListener *listener,
881                                        MemoryRegionSection *section)
882 {
883     VFIODirtyRangesListener *dirty =
884         container_of(listener, VFIODirtyRangesListener, listener);
885     hwaddr iova, end;
886 
887     if (!vfio_listener_valid_section(section, "tracking_update") ||
888         !vfio_get_section_iova_range(dirty->bcontainer, section,
889                                      &iova, &end, NULL)) {
890         return;
891     }
892 
893     vfio_dirty_tracking_update_range(&dirty->ranges, iova, end,
894                       vfio_section_is_vfio_pci(section, dirty->bcontainer));
895 }
896 
897 static const MemoryListener vfio_dirty_tracking_listener = {
898     .name = "vfio-tracking",
899     .region_add = vfio_dirty_tracking_update,
900 };
901 
vfio_dirty_tracking_init(VFIOContainerBase * bcontainer,VFIODirtyRanges * ranges)902 static void vfio_dirty_tracking_init(VFIOContainerBase *bcontainer,
903                                      VFIODirtyRanges *ranges)
904 {
905     VFIODirtyRangesListener dirty;
906 
907     memset(&dirty, 0, sizeof(dirty));
908     dirty.ranges.min32 = UINT32_MAX;
909     dirty.ranges.min64 = UINT64_MAX;
910     dirty.ranges.minpci64 = UINT64_MAX;
911     dirty.listener = vfio_dirty_tracking_listener;
912     dirty.bcontainer = bcontainer;
913 
914     memory_listener_register(&dirty.listener,
915                              bcontainer->space->as);
916 
917     *ranges = dirty.ranges;
918 
919     /*
920      * The memory listener is synchronous, and used to calculate the range
921      * to dirty tracking. Unregister it after we are done as we are not
922      * interested in any follow-up updates.
923      */
924     memory_listener_unregister(&dirty.listener);
925 }
926 
vfio_devices_dma_logging_stop(VFIOContainerBase * bcontainer)927 static void vfio_devices_dma_logging_stop(VFIOContainerBase *bcontainer)
928 {
929     uint64_t buf[DIV_ROUND_UP(sizeof(struct vfio_device_feature),
930                               sizeof(uint64_t))] = {};
931     struct vfio_device_feature *feature = (struct vfio_device_feature *)buf;
932     VFIODevice *vbasedev;
933 
934     feature->argsz = sizeof(buf);
935     feature->flags = VFIO_DEVICE_FEATURE_SET |
936                      VFIO_DEVICE_FEATURE_DMA_LOGGING_STOP;
937 
938     QLIST_FOREACH(vbasedev, &bcontainer->device_list, container_next) {
939         if (!vbasedev->dirty_tracking) {
940             continue;
941         }
942 
943         if (ioctl(vbasedev->fd, VFIO_DEVICE_FEATURE, feature)) {
944             warn_report("%s: Failed to stop DMA logging, err %d (%s)",
945                         vbasedev->name, -errno, strerror(errno));
946         }
947         vbasedev->dirty_tracking = false;
948     }
949 }
950 
951 static struct vfio_device_feature *
vfio_device_feature_dma_logging_start_create(VFIOContainerBase * bcontainer,VFIODirtyRanges * tracking)952 vfio_device_feature_dma_logging_start_create(VFIOContainerBase *bcontainer,
953                                              VFIODirtyRanges *tracking)
954 {
955     struct vfio_device_feature *feature;
956     size_t feature_size;
957     struct vfio_device_feature_dma_logging_control *control;
958     struct vfio_device_feature_dma_logging_range *ranges;
959 
960     feature_size = sizeof(struct vfio_device_feature) +
961                    sizeof(struct vfio_device_feature_dma_logging_control);
962     feature = g_try_malloc0(feature_size);
963     if (!feature) {
964         errno = ENOMEM;
965         return NULL;
966     }
967     feature->argsz = feature_size;
968     feature->flags = VFIO_DEVICE_FEATURE_SET |
969                      VFIO_DEVICE_FEATURE_DMA_LOGGING_START;
970 
971     control = (struct vfio_device_feature_dma_logging_control *)feature->data;
972     control->page_size = qemu_real_host_page_size();
973 
974     /*
975      * DMA logging uAPI guarantees to support at least a number of ranges that
976      * fits into a single host kernel base page.
977      */
978     control->num_ranges = !!tracking->max32 + !!tracking->max64 +
979         !!tracking->maxpci64;
980     ranges = g_try_new0(struct vfio_device_feature_dma_logging_range,
981                         control->num_ranges);
982     if (!ranges) {
983         g_free(feature);
984         errno = ENOMEM;
985 
986         return NULL;
987     }
988 
989     control->ranges = (uintptr_t)ranges;
990     if (tracking->max32) {
991         ranges->iova = tracking->min32;
992         ranges->length = (tracking->max32 - tracking->min32) + 1;
993         ranges++;
994     }
995     if (tracking->max64) {
996         ranges->iova = tracking->min64;
997         ranges->length = (tracking->max64 - tracking->min64) + 1;
998         ranges++;
999     }
1000     if (tracking->maxpci64) {
1001         ranges->iova = tracking->minpci64;
1002         ranges->length = (tracking->maxpci64 - tracking->minpci64) + 1;
1003     }
1004 
1005     trace_vfio_device_dirty_tracking_start(control->num_ranges,
1006                                            tracking->min32, tracking->max32,
1007                                            tracking->min64, tracking->max64,
1008                                            tracking->minpci64, tracking->maxpci64);
1009 
1010     return feature;
1011 }
1012 
vfio_device_feature_dma_logging_start_destroy(struct vfio_device_feature * feature)1013 static void vfio_device_feature_dma_logging_start_destroy(
1014     struct vfio_device_feature *feature)
1015 {
1016     struct vfio_device_feature_dma_logging_control *control =
1017         (struct vfio_device_feature_dma_logging_control *)feature->data;
1018     struct vfio_device_feature_dma_logging_range *ranges =
1019         (struct vfio_device_feature_dma_logging_range *)(uintptr_t)control->ranges;
1020 
1021     g_free(ranges);
1022     g_free(feature);
1023 }
1024 
vfio_devices_dma_logging_start(VFIOContainerBase * bcontainer,Error ** errp)1025 static bool vfio_devices_dma_logging_start(VFIOContainerBase *bcontainer,
1026                                           Error **errp)
1027 {
1028     struct vfio_device_feature *feature;
1029     VFIODirtyRanges ranges;
1030     VFIODevice *vbasedev;
1031     int ret = 0;
1032 
1033     vfio_dirty_tracking_init(bcontainer, &ranges);
1034     feature = vfio_device_feature_dma_logging_start_create(bcontainer,
1035                                                            &ranges);
1036     if (!feature) {
1037         error_setg_errno(errp, errno, "Failed to prepare DMA logging");
1038         return false;
1039     }
1040 
1041     QLIST_FOREACH(vbasedev, &bcontainer->device_list, container_next) {
1042         if (vbasedev->dirty_tracking) {
1043             continue;
1044         }
1045 
1046         ret = ioctl(vbasedev->fd, VFIO_DEVICE_FEATURE, feature);
1047         if (ret) {
1048             ret = -errno;
1049             error_setg_errno(errp, errno, "%s: Failed to start DMA logging",
1050                              vbasedev->name);
1051             goto out;
1052         }
1053         vbasedev->dirty_tracking = true;
1054     }
1055 
1056 out:
1057     if (ret) {
1058         vfio_devices_dma_logging_stop(bcontainer);
1059     }
1060 
1061     vfio_device_feature_dma_logging_start_destroy(feature);
1062 
1063     return ret == 0;
1064 }
1065 
vfio_listener_log_global_start(MemoryListener * listener,Error ** errp)1066 static bool vfio_listener_log_global_start(MemoryListener *listener,
1067                                            Error **errp)
1068 {
1069     ERRP_GUARD();
1070     VFIOContainerBase *bcontainer = container_of(listener, VFIOContainerBase,
1071                                                  listener);
1072     bool ret;
1073 
1074     if (vfio_devices_all_device_dirty_tracking(bcontainer)) {
1075         ret = vfio_devices_dma_logging_start(bcontainer, errp);
1076     } else {
1077         ret = vfio_container_set_dirty_page_tracking(bcontainer, true, errp) == 0;
1078     }
1079 
1080     if (!ret) {
1081         error_prepend(errp, "vfio: Could not start dirty page tracking - ");
1082     }
1083     return ret;
1084 }
1085 
vfio_listener_log_global_stop(MemoryListener * listener)1086 static void vfio_listener_log_global_stop(MemoryListener *listener)
1087 {
1088     VFIOContainerBase *bcontainer = container_of(listener, VFIOContainerBase,
1089                                                  listener);
1090     Error *local_err = NULL;
1091     int ret = 0;
1092 
1093     if (vfio_devices_all_device_dirty_tracking(bcontainer)) {
1094         vfio_devices_dma_logging_stop(bcontainer);
1095     } else {
1096         ret = vfio_container_set_dirty_page_tracking(bcontainer, false,
1097                                                      &local_err);
1098     }
1099 
1100     if (ret) {
1101         error_prepend(&local_err,
1102                       "vfio: Could not stop dirty page tracking - ");
1103         error_report_err(local_err);
1104         vfio_set_migration_error(ret);
1105     }
1106 }
1107 
vfio_device_dma_logging_report(VFIODevice * vbasedev,hwaddr iova,hwaddr size,void * bitmap)1108 static int vfio_device_dma_logging_report(VFIODevice *vbasedev, hwaddr iova,
1109                                           hwaddr size, void *bitmap)
1110 {
1111     uint64_t buf[DIV_ROUND_UP(sizeof(struct vfio_device_feature) +
1112                         sizeof(struct vfio_device_feature_dma_logging_report),
1113                         sizeof(uint64_t))] = {};
1114     struct vfio_device_feature *feature = (struct vfio_device_feature *)buf;
1115     struct vfio_device_feature_dma_logging_report *report =
1116         (struct vfio_device_feature_dma_logging_report *)feature->data;
1117 
1118     report->iova = iova;
1119     report->length = size;
1120     report->page_size = qemu_real_host_page_size();
1121     report->bitmap = (uintptr_t)bitmap;
1122 
1123     feature->argsz = sizeof(buf);
1124     feature->flags = VFIO_DEVICE_FEATURE_GET |
1125                      VFIO_DEVICE_FEATURE_DMA_LOGGING_REPORT;
1126 
1127     if (ioctl(vbasedev->fd, VFIO_DEVICE_FEATURE, feature)) {
1128         return -errno;
1129     }
1130 
1131     return 0;
1132 }
1133 
vfio_devices_query_dirty_bitmap(const VFIOContainerBase * bcontainer,VFIOBitmap * vbmap,hwaddr iova,hwaddr size,Error ** errp)1134 int vfio_devices_query_dirty_bitmap(const VFIOContainerBase *bcontainer,
1135                  VFIOBitmap *vbmap, hwaddr iova, hwaddr size, Error **errp)
1136 {
1137     VFIODevice *vbasedev;
1138     int ret;
1139 
1140     QLIST_FOREACH(vbasedev, &bcontainer->device_list, container_next) {
1141         ret = vfio_device_dma_logging_report(vbasedev, iova, size,
1142                                              vbmap->bitmap);
1143         if (ret) {
1144             error_setg_errno(errp, -ret,
1145                              "%s: Failed to get DMA logging report, iova: "
1146                              "0x%" HWADDR_PRIx ", size: 0x%" HWADDR_PRIx,
1147                              vbasedev->name, iova, size);
1148 
1149             return ret;
1150         }
1151     }
1152 
1153     return 0;
1154 }
1155 
vfio_get_dirty_bitmap(const VFIOContainerBase * bcontainer,uint64_t iova,uint64_t size,ram_addr_t ram_addr,Error ** errp)1156 int vfio_get_dirty_bitmap(const VFIOContainerBase *bcontainer, uint64_t iova,
1157                           uint64_t size, ram_addr_t ram_addr, Error **errp)
1158 {
1159     bool all_device_dirty_tracking =
1160         vfio_devices_all_device_dirty_tracking(bcontainer);
1161     uint64_t dirty_pages;
1162     VFIOBitmap vbmap;
1163     int ret;
1164 
1165     if (!bcontainer->dirty_pages_supported && !all_device_dirty_tracking) {
1166         cpu_physical_memory_set_dirty_range(ram_addr, size,
1167                                             tcg_enabled() ? DIRTY_CLIENTS_ALL :
1168                                             DIRTY_CLIENTS_NOCODE);
1169         return 0;
1170     }
1171 
1172     ret = vfio_bitmap_alloc(&vbmap, size);
1173     if (ret) {
1174         error_setg_errno(errp, -ret,
1175                          "Failed to allocate dirty tracking bitmap");
1176         return ret;
1177     }
1178 
1179     if (all_device_dirty_tracking) {
1180         ret = vfio_devices_query_dirty_bitmap(bcontainer, &vbmap, iova, size,
1181                                               errp);
1182     } else {
1183         ret = vfio_container_query_dirty_bitmap(bcontainer, &vbmap, iova, size,
1184                                                 errp);
1185     }
1186 
1187     if (ret) {
1188         goto out;
1189     }
1190 
1191     dirty_pages = cpu_physical_memory_set_dirty_lebitmap(vbmap.bitmap, ram_addr,
1192                                                          vbmap.pages);
1193 
1194     trace_vfio_get_dirty_bitmap(iova, size, vbmap.size, ram_addr, dirty_pages);
1195 out:
1196     g_free(vbmap.bitmap);
1197 
1198     return ret;
1199 }
1200 
1201 typedef struct {
1202     IOMMUNotifier n;
1203     VFIOGuestIOMMU *giommu;
1204 } vfio_giommu_dirty_notifier;
1205 
vfio_iommu_map_dirty_notify(IOMMUNotifier * n,IOMMUTLBEntry * iotlb)1206 static void vfio_iommu_map_dirty_notify(IOMMUNotifier *n, IOMMUTLBEntry *iotlb)
1207 {
1208     vfio_giommu_dirty_notifier *gdn = container_of(n,
1209                                                 vfio_giommu_dirty_notifier, n);
1210     VFIOGuestIOMMU *giommu = gdn->giommu;
1211     VFIOContainerBase *bcontainer = giommu->bcontainer;
1212     hwaddr iova = iotlb->iova + giommu->iommu_offset;
1213     ram_addr_t translated_addr;
1214     Error *local_err = NULL;
1215     int ret = -EINVAL;
1216 
1217     trace_vfio_iommu_map_dirty_notify(iova, iova + iotlb->addr_mask);
1218 
1219     if (iotlb->target_as != &address_space_memory) {
1220         error_report("Wrong target AS \"%s\", only system memory is allowed",
1221                      iotlb->target_as->name ? iotlb->target_as->name : "none");
1222         goto out;
1223     }
1224 
1225     rcu_read_lock();
1226     if (!vfio_get_xlat_addr(iotlb, NULL, &translated_addr, NULL, &local_err)) {
1227         error_report_err(local_err);
1228         goto out_unlock;
1229     }
1230 
1231     ret = vfio_get_dirty_bitmap(bcontainer, iova, iotlb->addr_mask + 1,
1232                                 translated_addr, &local_err);
1233     if (ret) {
1234         error_prepend(&local_err,
1235                       "vfio_iommu_map_dirty_notify(%p, 0x%"HWADDR_PRIx", "
1236                       "0x%"HWADDR_PRIx") failed - ", bcontainer, iova,
1237                       iotlb->addr_mask + 1);
1238         error_report_err(local_err);
1239     }
1240 
1241 out_unlock:
1242     rcu_read_unlock();
1243 
1244 out:
1245     if (ret) {
1246         vfio_set_migration_error(ret);
1247     }
1248 }
1249 
vfio_ram_discard_get_dirty_bitmap(MemoryRegionSection * section,void * opaque)1250 static int vfio_ram_discard_get_dirty_bitmap(MemoryRegionSection *section,
1251                                              void *opaque)
1252 {
1253     const hwaddr size = int128_get64(section->size);
1254     const hwaddr iova = section->offset_within_address_space;
1255     const ram_addr_t ram_addr = memory_region_get_ram_addr(section->mr) +
1256                                 section->offset_within_region;
1257     VFIORamDiscardListener *vrdl = opaque;
1258     Error *local_err = NULL;
1259     int ret;
1260 
1261     /*
1262      * Sync the whole mapped region (spanning multiple individual mappings)
1263      * in one go.
1264      */
1265     ret = vfio_get_dirty_bitmap(vrdl->bcontainer, iova, size, ram_addr,
1266                                 &local_err);
1267     if (ret) {
1268         error_report_err(local_err);
1269     }
1270     return ret;
1271 }
1272 
1273 static int
vfio_sync_ram_discard_listener_dirty_bitmap(VFIOContainerBase * bcontainer,MemoryRegionSection * section)1274 vfio_sync_ram_discard_listener_dirty_bitmap(VFIOContainerBase *bcontainer,
1275                                             MemoryRegionSection *section)
1276 {
1277     RamDiscardManager *rdm = memory_region_get_ram_discard_manager(section->mr);
1278     VFIORamDiscardListener *vrdl = NULL;
1279 
1280     QLIST_FOREACH(vrdl, &bcontainer->vrdl_list, next) {
1281         if (vrdl->mr == section->mr &&
1282             vrdl->offset_within_address_space ==
1283             section->offset_within_address_space) {
1284             break;
1285         }
1286     }
1287 
1288     if (!vrdl) {
1289         hw_error("vfio: Trying to sync missing RAM discard listener");
1290     }
1291 
1292     /*
1293      * We only want/can synchronize the bitmap for actually mapped parts -
1294      * which correspond to populated parts. Replay all populated parts.
1295      */
1296     return ram_discard_manager_replay_populated(rdm, section,
1297                                               vfio_ram_discard_get_dirty_bitmap,
1298                                                 &vrdl);
1299 }
1300 
vfio_sync_iommu_dirty_bitmap(VFIOContainerBase * bcontainer,MemoryRegionSection * section)1301 static int vfio_sync_iommu_dirty_bitmap(VFIOContainerBase *bcontainer,
1302                                         MemoryRegionSection *section)
1303 {
1304     VFIOGuestIOMMU *giommu;
1305     bool found = false;
1306     Int128 llend;
1307     vfio_giommu_dirty_notifier gdn;
1308     int idx;
1309 
1310     QLIST_FOREACH(giommu, &bcontainer->giommu_list, giommu_next) {
1311         if (MEMORY_REGION(giommu->iommu_mr) == section->mr &&
1312             giommu->n.start == section->offset_within_region) {
1313             found = true;
1314             break;
1315         }
1316     }
1317 
1318     if (!found) {
1319         return 0;
1320     }
1321 
1322     gdn.giommu = giommu;
1323     idx = memory_region_iommu_attrs_to_index(giommu->iommu_mr,
1324                                              MEMTXATTRS_UNSPECIFIED);
1325 
1326     llend = int128_add(int128_make64(section->offset_within_region),
1327                        section->size);
1328     llend = int128_sub(llend, int128_one());
1329 
1330     iommu_notifier_init(&gdn.n, vfio_iommu_map_dirty_notify, IOMMU_NOTIFIER_MAP,
1331                         section->offset_within_region, int128_get64(llend),
1332                         idx);
1333     memory_region_iommu_replay(giommu->iommu_mr, &gdn.n);
1334 
1335     return 0;
1336 }
1337 
vfio_sync_dirty_bitmap(VFIOContainerBase * bcontainer,MemoryRegionSection * section,Error ** errp)1338 static int vfio_sync_dirty_bitmap(VFIOContainerBase *bcontainer,
1339                                   MemoryRegionSection *section, Error **errp)
1340 {
1341     ram_addr_t ram_addr;
1342 
1343     if (memory_region_is_iommu(section->mr)) {
1344         return vfio_sync_iommu_dirty_bitmap(bcontainer, section);
1345     } else if (memory_region_has_ram_discard_manager(section->mr)) {
1346         int ret;
1347 
1348         ret = vfio_sync_ram_discard_listener_dirty_bitmap(bcontainer, section);
1349         if (ret) {
1350             error_setg(errp,
1351                        "Failed to sync dirty bitmap with RAM discard listener");
1352         }
1353         return ret;
1354     }
1355 
1356     ram_addr = memory_region_get_ram_addr(section->mr) +
1357                section->offset_within_region;
1358 
1359     return vfio_get_dirty_bitmap(bcontainer,
1360                    REAL_HOST_PAGE_ALIGN(section->offset_within_address_space),
1361                                  int128_get64(section->size), ram_addr, errp);
1362 }
1363 
vfio_listener_log_sync(MemoryListener * listener,MemoryRegionSection * section)1364 static void vfio_listener_log_sync(MemoryListener *listener,
1365         MemoryRegionSection *section)
1366 {
1367     VFIOContainerBase *bcontainer = container_of(listener, VFIOContainerBase,
1368                                                  listener);
1369     int ret;
1370     Error *local_err = NULL;
1371 
1372     if (vfio_listener_skipped_section(section)) {
1373         return;
1374     }
1375 
1376     if (vfio_devices_all_dirty_tracking(bcontainer)) {
1377         ret = vfio_sync_dirty_bitmap(bcontainer, section, &local_err);
1378         if (ret) {
1379             error_report_err(local_err);
1380             vfio_set_migration_error(ret);
1381         }
1382     }
1383 }
1384 
1385 const MemoryListener vfio_memory_listener = {
1386     .name = "vfio",
1387     .region_add = vfio_listener_region_add,
1388     .region_del = vfio_listener_region_del,
1389     .log_global_start = vfio_listener_log_global_start,
1390     .log_global_stop = vfio_listener_log_global_stop,
1391     .log_sync = vfio_listener_log_sync,
1392 };
1393 
vfio_reset_handler(void * opaque)1394 void vfio_reset_handler(void *opaque)
1395 {
1396     VFIODevice *vbasedev;
1397 
1398     QLIST_FOREACH(vbasedev, &vfio_device_list, global_next) {
1399         if (vbasedev->dev->realized) {
1400             vbasedev->ops->vfio_compute_needs_reset(vbasedev);
1401         }
1402     }
1403 
1404     QLIST_FOREACH(vbasedev, &vfio_device_list, global_next) {
1405         if (vbasedev->dev->realized && vbasedev->needs_reset) {
1406             vbasedev->ops->vfio_hot_reset_multi(vbasedev);
1407         }
1408     }
1409 }
1410 
vfio_kvm_device_add_fd(int fd,Error ** errp)1411 int vfio_kvm_device_add_fd(int fd, Error **errp)
1412 {
1413 #ifdef CONFIG_KVM
1414     struct kvm_device_attr attr = {
1415         .group = KVM_DEV_VFIO_FILE,
1416         .attr = KVM_DEV_VFIO_FILE_ADD,
1417         .addr = (uint64_t)(unsigned long)&fd,
1418     };
1419 
1420     if (!kvm_enabled()) {
1421         return 0;
1422     }
1423 
1424     if (vfio_kvm_device_fd < 0) {
1425         struct kvm_create_device cd = {
1426             .type = KVM_DEV_TYPE_VFIO,
1427         };
1428 
1429         if (kvm_vm_ioctl(kvm_state, KVM_CREATE_DEVICE, &cd)) {
1430             error_setg_errno(errp, errno, "Failed to create KVM VFIO device");
1431             return -errno;
1432         }
1433 
1434         vfio_kvm_device_fd = cd.fd;
1435     }
1436 
1437     if (ioctl(vfio_kvm_device_fd, KVM_SET_DEVICE_ATTR, &attr)) {
1438         error_setg_errno(errp, errno, "Failed to add fd %d to KVM VFIO device",
1439                          fd);
1440         return -errno;
1441     }
1442 #endif
1443     return 0;
1444 }
1445 
vfio_kvm_device_del_fd(int fd,Error ** errp)1446 int vfio_kvm_device_del_fd(int fd, Error **errp)
1447 {
1448 #ifdef CONFIG_KVM
1449     struct kvm_device_attr attr = {
1450         .group = KVM_DEV_VFIO_FILE,
1451         .attr = KVM_DEV_VFIO_FILE_DEL,
1452         .addr = (uint64_t)(unsigned long)&fd,
1453     };
1454 
1455     if (vfio_kvm_device_fd < 0) {
1456         error_setg(errp, "KVM VFIO device isn't created yet");
1457         return -EINVAL;
1458     }
1459 
1460     if (ioctl(vfio_kvm_device_fd, KVM_SET_DEVICE_ATTR, &attr)) {
1461         error_setg_errno(errp, errno,
1462                          "Failed to remove fd %d from KVM VFIO device", fd);
1463         return -errno;
1464     }
1465 #endif
1466     return 0;
1467 }
1468 
vfio_get_address_space(AddressSpace * as)1469 VFIOAddressSpace *vfio_get_address_space(AddressSpace *as)
1470 {
1471     VFIOAddressSpace *space;
1472 
1473     QLIST_FOREACH(space, &vfio_address_spaces, list) {
1474         if (space->as == as) {
1475             return space;
1476         }
1477     }
1478 
1479     /* No suitable VFIOAddressSpace, create a new one */
1480     space = g_malloc0(sizeof(*space));
1481     space->as = as;
1482     QLIST_INIT(&space->containers);
1483 
1484     if (QLIST_EMPTY(&vfio_address_spaces)) {
1485         qemu_register_reset(vfio_reset_handler, NULL);
1486     }
1487 
1488     QLIST_INSERT_HEAD(&vfio_address_spaces, space, list);
1489 
1490     return space;
1491 }
1492 
vfio_put_address_space(VFIOAddressSpace * space)1493 void vfio_put_address_space(VFIOAddressSpace *space)
1494 {
1495     if (!QLIST_EMPTY(&space->containers)) {
1496         return;
1497     }
1498 
1499     QLIST_REMOVE(space, list);
1500     g_free(space);
1501 
1502     if (QLIST_EMPTY(&vfio_address_spaces)) {
1503         qemu_unregister_reset(vfio_reset_handler, NULL);
1504     }
1505 }
1506 
vfio_address_space_insert(VFIOAddressSpace * space,VFIOContainerBase * bcontainer)1507 void vfio_address_space_insert(VFIOAddressSpace *space,
1508                                VFIOContainerBase *bcontainer)
1509 {
1510     QLIST_INSERT_HEAD(&space->containers, bcontainer, next);
1511     bcontainer->space = space;
1512 }
1513 
vfio_get_device_info(int fd)1514 struct vfio_device_info *vfio_get_device_info(int fd)
1515 {
1516     struct vfio_device_info *info;
1517     uint32_t argsz = sizeof(*info);
1518 
1519     info = g_malloc0(argsz);
1520 
1521 retry:
1522     info->argsz = argsz;
1523 
1524     if (ioctl(fd, VFIO_DEVICE_GET_INFO, info)) {
1525         g_free(info);
1526         return NULL;
1527     }
1528 
1529     if (info->argsz > argsz) {
1530         argsz = info->argsz;
1531         info = g_realloc(info, argsz);
1532         goto retry;
1533     }
1534 
1535     return info;
1536 }
1537 
vfio_attach_device(char * name,VFIODevice * vbasedev,AddressSpace * as,Error ** errp)1538 bool vfio_attach_device(char *name, VFIODevice *vbasedev,
1539                         AddressSpace *as, Error **errp)
1540 {
1541     const VFIOIOMMUClass *ops =
1542         VFIO_IOMMU_CLASS(object_class_by_name(TYPE_VFIO_IOMMU_LEGACY));
1543     HostIOMMUDevice *hiod = NULL;
1544 
1545     if (vbasedev->iommufd) {
1546         ops = VFIO_IOMMU_CLASS(object_class_by_name(TYPE_VFIO_IOMMU_IOMMUFD));
1547     }
1548 
1549     assert(ops);
1550 
1551 
1552     if (!vbasedev->mdev) {
1553         hiod = HOST_IOMMU_DEVICE(object_new(ops->hiod_typename));
1554         vbasedev->hiod = hiod;
1555     }
1556 
1557     if (!ops->attach_device(name, vbasedev, as, errp)) {
1558         object_unref(hiod);
1559         vbasedev->hiod = NULL;
1560         return false;
1561     }
1562 
1563     return true;
1564 }
1565 
vfio_detach_device(VFIODevice * vbasedev)1566 void vfio_detach_device(VFIODevice *vbasedev)
1567 {
1568     if (!vbasedev->bcontainer) {
1569         return;
1570     }
1571     object_unref(vbasedev->hiod);
1572     VFIO_IOMMU_GET_CLASS(vbasedev->bcontainer)->detach_device(vbasedev);
1573 }
1574