xref: /qemu/hw/vfio/common.c (revision 2e8f72ac)
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/vfio.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 "trace.h"
40 #include "qapi/error.h"
41 #include "migration/migration.h"
42 
43 VFIOGroupList vfio_group_list =
44     QLIST_HEAD_INITIALIZER(vfio_group_list);
45 static QLIST_HEAD(, VFIOAddressSpace) vfio_address_spaces =
46     QLIST_HEAD_INITIALIZER(vfio_address_spaces);
47 
48 #ifdef CONFIG_KVM
49 /*
50  * We have a single VFIO pseudo device per KVM VM.  Once created it lives
51  * for the life of the VM.  Closing the file descriptor only drops our
52  * reference to it and the device's reference to kvm.  Therefore once
53  * initialized, this file descriptor is only released on QEMU exit and
54  * we'll re-use it should another vfio device be attached before then.
55  */
56 static int vfio_kvm_device_fd = -1;
57 #endif
58 
59 /*
60  * Common VFIO interrupt disable
61  */
62 void vfio_disable_irqindex(VFIODevice *vbasedev, int index)
63 {
64     struct vfio_irq_set irq_set = {
65         .argsz = sizeof(irq_set),
66         .flags = VFIO_IRQ_SET_DATA_NONE | VFIO_IRQ_SET_ACTION_TRIGGER,
67         .index = index,
68         .start = 0,
69         .count = 0,
70     };
71 
72     ioctl(vbasedev->fd, VFIO_DEVICE_SET_IRQS, &irq_set);
73 }
74 
75 void vfio_unmask_single_irqindex(VFIODevice *vbasedev, int index)
76 {
77     struct vfio_irq_set irq_set = {
78         .argsz = sizeof(irq_set),
79         .flags = VFIO_IRQ_SET_DATA_NONE | VFIO_IRQ_SET_ACTION_UNMASK,
80         .index = index,
81         .start = 0,
82         .count = 1,
83     };
84 
85     ioctl(vbasedev->fd, VFIO_DEVICE_SET_IRQS, &irq_set);
86 }
87 
88 void vfio_mask_single_irqindex(VFIODevice *vbasedev, int index)
89 {
90     struct vfio_irq_set irq_set = {
91         .argsz = sizeof(irq_set),
92         .flags = VFIO_IRQ_SET_DATA_NONE | VFIO_IRQ_SET_ACTION_MASK,
93         .index = index,
94         .start = 0,
95         .count = 1,
96     };
97 
98     ioctl(vbasedev->fd, VFIO_DEVICE_SET_IRQS, &irq_set);
99 }
100 
101 static inline const char *action_to_str(int action)
102 {
103     switch (action) {
104     case VFIO_IRQ_SET_ACTION_MASK:
105         return "MASK";
106     case VFIO_IRQ_SET_ACTION_UNMASK:
107         return "UNMASK";
108     case VFIO_IRQ_SET_ACTION_TRIGGER:
109         return "TRIGGER";
110     default:
111         return "UNKNOWN ACTION";
112     }
113 }
114 
115 static const char *index_to_str(VFIODevice *vbasedev, int index)
116 {
117     if (vbasedev->type != VFIO_DEVICE_TYPE_PCI) {
118         return NULL;
119     }
120 
121     switch (index) {
122     case VFIO_PCI_INTX_IRQ_INDEX:
123         return "INTX";
124     case VFIO_PCI_MSI_IRQ_INDEX:
125         return "MSI";
126     case VFIO_PCI_MSIX_IRQ_INDEX:
127         return "MSIX";
128     case VFIO_PCI_ERR_IRQ_INDEX:
129         return "ERR";
130     case VFIO_PCI_REQ_IRQ_INDEX:
131         return "REQ";
132     default:
133         return NULL;
134     }
135 }
136 
137 int vfio_set_irq_signaling(VFIODevice *vbasedev, int index, int subindex,
138                            int action, int fd, Error **errp)
139 {
140     struct vfio_irq_set *irq_set;
141     int argsz, ret = 0;
142     const char *name;
143     int32_t *pfd;
144 
145     argsz = sizeof(*irq_set) + sizeof(*pfd);
146 
147     irq_set = g_malloc0(argsz);
148     irq_set->argsz = argsz;
149     irq_set->flags = VFIO_IRQ_SET_DATA_EVENTFD | action;
150     irq_set->index = index;
151     irq_set->start = subindex;
152     irq_set->count = 1;
153     pfd = (int32_t *)&irq_set->data;
154     *pfd = fd;
155 
156     if (ioctl(vbasedev->fd, VFIO_DEVICE_SET_IRQS, irq_set)) {
157         ret = -errno;
158     }
159     g_free(irq_set);
160 
161     if (!ret) {
162         return 0;
163     }
164 
165     error_setg_errno(errp, -ret, "VFIO_DEVICE_SET_IRQS failure");
166 
167     name = index_to_str(vbasedev, index);
168     if (name) {
169         error_prepend(errp, "%s-%d: ", name, subindex);
170     } else {
171         error_prepend(errp, "index %d-%d: ", index, subindex);
172     }
173     error_prepend(errp,
174                   "Failed to %s %s eventfd signaling for interrupt ",
175                   fd < 0 ? "tear down" : "set up", action_to_str(action));
176     return ret;
177 }
178 
179 /*
180  * IO Port/MMIO - Beware of the endians, VFIO is always little endian
181  */
182 void vfio_region_write(void *opaque, hwaddr addr,
183                        uint64_t data, unsigned size)
184 {
185     VFIORegion *region = opaque;
186     VFIODevice *vbasedev = region->vbasedev;
187     union {
188         uint8_t byte;
189         uint16_t word;
190         uint32_t dword;
191         uint64_t qword;
192     } buf;
193 
194     switch (size) {
195     case 1:
196         buf.byte = data;
197         break;
198     case 2:
199         buf.word = cpu_to_le16(data);
200         break;
201     case 4:
202         buf.dword = cpu_to_le32(data);
203         break;
204     case 8:
205         buf.qword = cpu_to_le64(data);
206         break;
207     default:
208         hw_error("vfio: unsupported write size, %u bytes", size);
209         break;
210     }
211 
212     if (pwrite(vbasedev->fd, &buf, size, region->fd_offset + addr) != size) {
213         error_report("%s(%s:region%d+0x%"HWADDR_PRIx", 0x%"PRIx64
214                      ",%d) failed: %m",
215                      __func__, vbasedev->name, region->nr,
216                      addr, data, size);
217     }
218 
219     trace_vfio_region_write(vbasedev->name, region->nr, addr, data, size);
220 
221     /*
222      * A read or write to a BAR always signals an INTx EOI.  This will
223      * do nothing if not pending (including not in INTx mode).  We assume
224      * that a BAR access is in response to an interrupt and that BAR
225      * accesses will service the interrupt.  Unfortunately, we don't know
226      * which access will service the interrupt, so we're potentially
227      * getting quite a few host interrupts per guest interrupt.
228      */
229     vbasedev->ops->vfio_eoi(vbasedev);
230 }
231 
232 uint64_t vfio_region_read(void *opaque,
233                           hwaddr addr, unsigned size)
234 {
235     VFIORegion *region = opaque;
236     VFIODevice *vbasedev = region->vbasedev;
237     union {
238         uint8_t byte;
239         uint16_t word;
240         uint32_t dword;
241         uint64_t qword;
242     } buf;
243     uint64_t data = 0;
244 
245     if (pread(vbasedev->fd, &buf, size, region->fd_offset + addr) != size) {
246         error_report("%s(%s:region%d+0x%"HWADDR_PRIx", %d) failed: %m",
247                      __func__, vbasedev->name, region->nr,
248                      addr, size);
249         return (uint64_t)-1;
250     }
251     switch (size) {
252     case 1:
253         data = buf.byte;
254         break;
255     case 2:
256         data = le16_to_cpu(buf.word);
257         break;
258     case 4:
259         data = le32_to_cpu(buf.dword);
260         break;
261     case 8:
262         data = le64_to_cpu(buf.qword);
263         break;
264     default:
265         hw_error("vfio: unsupported read size, %u bytes", size);
266         break;
267     }
268 
269     trace_vfio_region_read(vbasedev->name, region->nr, addr, size, data);
270 
271     /* Same as write above */
272     vbasedev->ops->vfio_eoi(vbasedev);
273 
274     return data;
275 }
276 
277 const MemoryRegionOps vfio_region_ops = {
278     .read = vfio_region_read,
279     .write = vfio_region_write,
280     .endianness = DEVICE_LITTLE_ENDIAN,
281     .valid = {
282         .min_access_size = 1,
283         .max_access_size = 8,
284     },
285     .impl = {
286         .min_access_size = 1,
287         .max_access_size = 8,
288     },
289 };
290 
291 /*
292  * Device state interfaces
293  */
294 
295 bool vfio_mig_active(void)
296 {
297     VFIOGroup *group;
298     VFIODevice *vbasedev;
299 
300     if (QLIST_EMPTY(&vfio_group_list)) {
301         return false;
302     }
303 
304     QLIST_FOREACH(group, &vfio_group_list, next) {
305         QLIST_FOREACH(vbasedev, &group->device_list, next) {
306             if (vbasedev->migration_blocker) {
307                 return false;
308             }
309         }
310     }
311     return true;
312 }
313 
314 static bool vfio_devices_all_saving(VFIOContainer *container)
315 {
316     VFIOGroup *group;
317     VFIODevice *vbasedev;
318     MigrationState *ms = migrate_get_current();
319 
320     if (!migration_is_setup_or_active(ms->state)) {
321         return false;
322     }
323 
324     QLIST_FOREACH(group, &container->group_list, container_next) {
325         QLIST_FOREACH(vbasedev, &group->device_list, next) {
326             VFIOMigration *migration = vbasedev->migration;
327 
328             if (!migration) {
329                 return false;
330             }
331 
332             if (migration->device_state & VFIO_DEVICE_STATE_SAVING) {
333                 if ((vbasedev->pre_copy_dirty_page_tracking == ON_OFF_AUTO_OFF)
334                     && (migration->device_state & VFIO_DEVICE_STATE_RUNNING)) {
335                         return false;
336                 }
337                 continue;
338             } else {
339                 return false;
340             }
341         }
342     }
343     return true;
344 }
345 
346 static bool vfio_devices_all_running_and_saving(VFIOContainer *container)
347 {
348     VFIOGroup *group;
349     VFIODevice *vbasedev;
350     MigrationState *ms = migrate_get_current();
351 
352     if (!migration_is_setup_or_active(ms->state)) {
353         return false;
354     }
355 
356     QLIST_FOREACH(group, &container->group_list, container_next) {
357         QLIST_FOREACH(vbasedev, &group->device_list, next) {
358             VFIOMigration *migration = vbasedev->migration;
359 
360             if (!migration) {
361                 return false;
362             }
363 
364             if ((migration->device_state & VFIO_DEVICE_STATE_SAVING) &&
365                 (migration->device_state & VFIO_DEVICE_STATE_RUNNING)) {
366                 continue;
367             } else {
368                 return false;
369             }
370         }
371     }
372     return true;
373 }
374 
375 static int vfio_dma_unmap_bitmap(VFIOContainer *container,
376                                  hwaddr iova, ram_addr_t size,
377                                  IOMMUTLBEntry *iotlb)
378 {
379     struct vfio_iommu_type1_dma_unmap *unmap;
380     struct vfio_bitmap *bitmap;
381     uint64_t pages = TARGET_PAGE_ALIGN(size) >> TARGET_PAGE_BITS;
382     int ret;
383 
384     unmap = g_malloc0(sizeof(*unmap) + sizeof(*bitmap));
385 
386     unmap->argsz = sizeof(*unmap) + sizeof(*bitmap);
387     unmap->iova = iova;
388     unmap->size = size;
389     unmap->flags |= VFIO_DMA_UNMAP_FLAG_GET_DIRTY_BITMAP;
390     bitmap = (struct vfio_bitmap *)&unmap->data;
391 
392     /*
393      * cpu_physical_memory_set_dirty_lebitmap() expects pages in bitmap of
394      * TARGET_PAGE_SIZE to mark those dirty. Hence set bitmap_pgsize to
395      * TARGET_PAGE_SIZE.
396      */
397 
398     bitmap->pgsize = TARGET_PAGE_SIZE;
399     bitmap->size = ROUND_UP(pages, sizeof(__u64) * BITS_PER_BYTE) /
400                    BITS_PER_BYTE;
401 
402     if (bitmap->size > container->max_dirty_bitmap_size) {
403         error_report("UNMAP: Size of bitmap too big 0x%"PRIx64,
404                      (uint64_t)bitmap->size);
405         ret = -E2BIG;
406         goto unmap_exit;
407     }
408 
409     bitmap->data = g_try_malloc0(bitmap->size);
410     if (!bitmap->data) {
411         ret = -ENOMEM;
412         goto unmap_exit;
413     }
414 
415     ret = ioctl(container->fd, VFIO_IOMMU_UNMAP_DMA, unmap);
416     if (!ret) {
417         cpu_physical_memory_set_dirty_lebitmap((unsigned long *)bitmap->data,
418                 iotlb->translated_addr, pages);
419     } else {
420         error_report("VFIO_UNMAP_DMA with DIRTY_BITMAP : %m");
421     }
422 
423     g_free(bitmap->data);
424 unmap_exit:
425     g_free(unmap);
426     return ret;
427 }
428 
429 /*
430  * DMA - Mapping and unmapping for the "type1" IOMMU interface used on x86
431  */
432 static int vfio_dma_unmap(VFIOContainer *container,
433                           hwaddr iova, ram_addr_t size,
434                           IOMMUTLBEntry *iotlb)
435 {
436     struct vfio_iommu_type1_dma_unmap unmap = {
437         .argsz = sizeof(unmap),
438         .flags = 0,
439         .iova = iova,
440         .size = size,
441     };
442 
443     if (iotlb && container->dirty_pages_supported &&
444         vfio_devices_all_running_and_saving(container)) {
445         return vfio_dma_unmap_bitmap(container, iova, size, iotlb);
446     }
447 
448     while (ioctl(container->fd, VFIO_IOMMU_UNMAP_DMA, &unmap)) {
449         /*
450          * The type1 backend has an off-by-one bug in the kernel (71a7d3d78e3c
451          * v4.15) where an overflow in its wrap-around check prevents us from
452          * unmapping the last page of the address space.  Test for the error
453          * condition and re-try the unmap excluding the last page.  The
454          * expectation is that we've never mapped the last page anyway and this
455          * unmap request comes via vIOMMU support which also makes it unlikely
456          * that this page is used.  This bug was introduced well after type1 v2
457          * support was introduced, so we shouldn't need to test for v1.  A fix
458          * is queued for kernel v5.0 so this workaround can be removed once
459          * affected kernels are sufficiently deprecated.
460          */
461         if (errno == EINVAL && unmap.size && !(unmap.iova + unmap.size) &&
462             container->iommu_type == VFIO_TYPE1v2_IOMMU) {
463             trace_vfio_dma_unmap_overflow_workaround();
464             unmap.size -= 1ULL << ctz64(container->pgsizes);
465             continue;
466         }
467         error_report("VFIO_UNMAP_DMA failed: %s", strerror(errno));
468         return -errno;
469     }
470 
471     return 0;
472 }
473 
474 static int vfio_dma_map(VFIOContainer *container, hwaddr iova,
475                         ram_addr_t size, void *vaddr, bool readonly)
476 {
477     struct vfio_iommu_type1_dma_map map = {
478         .argsz = sizeof(map),
479         .flags = VFIO_DMA_MAP_FLAG_READ,
480         .vaddr = (__u64)(uintptr_t)vaddr,
481         .iova = iova,
482         .size = size,
483     };
484 
485     if (!readonly) {
486         map.flags |= VFIO_DMA_MAP_FLAG_WRITE;
487     }
488 
489     /*
490      * Try the mapping, if it fails with EBUSY, unmap the region and try
491      * again.  This shouldn't be necessary, but we sometimes see it in
492      * the VGA ROM space.
493      */
494     if (ioctl(container->fd, VFIO_IOMMU_MAP_DMA, &map) == 0 ||
495         (errno == EBUSY && vfio_dma_unmap(container, iova, size, NULL) == 0 &&
496          ioctl(container->fd, VFIO_IOMMU_MAP_DMA, &map) == 0)) {
497         return 0;
498     }
499 
500     error_report("VFIO_MAP_DMA failed: %s", strerror(errno));
501     return -errno;
502 }
503 
504 static void vfio_host_win_add(VFIOContainer *container,
505                               hwaddr min_iova, hwaddr max_iova,
506                               uint64_t iova_pgsizes)
507 {
508     VFIOHostDMAWindow *hostwin;
509 
510     QLIST_FOREACH(hostwin, &container->hostwin_list, hostwin_next) {
511         if (ranges_overlap(hostwin->min_iova,
512                            hostwin->max_iova - hostwin->min_iova + 1,
513                            min_iova,
514                            max_iova - min_iova + 1)) {
515             hw_error("%s: Overlapped IOMMU are not enabled", __func__);
516         }
517     }
518 
519     hostwin = g_malloc0(sizeof(*hostwin));
520 
521     hostwin->min_iova = min_iova;
522     hostwin->max_iova = max_iova;
523     hostwin->iova_pgsizes = iova_pgsizes;
524     QLIST_INSERT_HEAD(&container->hostwin_list, hostwin, hostwin_next);
525 }
526 
527 static int vfio_host_win_del(VFIOContainer *container, hwaddr min_iova,
528                              hwaddr max_iova)
529 {
530     VFIOHostDMAWindow *hostwin;
531 
532     QLIST_FOREACH(hostwin, &container->hostwin_list, hostwin_next) {
533         if (hostwin->min_iova == min_iova && hostwin->max_iova == max_iova) {
534             QLIST_REMOVE(hostwin, hostwin_next);
535             return 0;
536         }
537     }
538 
539     return -1;
540 }
541 
542 static bool vfio_listener_skipped_section(MemoryRegionSection *section)
543 {
544     return (!memory_region_is_ram(section->mr) &&
545             !memory_region_is_iommu(section->mr)) ||
546            /*
547             * Sizing an enabled 64-bit BAR can cause spurious mappings to
548             * addresses in the upper part of the 64-bit address space.  These
549             * are never accessed by the CPU and beyond the address width of
550             * some IOMMU hardware.  TODO: VFIO should tell us the IOMMU width.
551             */
552            section->offset_within_address_space & (1ULL << 63);
553 }
554 
555 /* Called with rcu_read_lock held.  */
556 static bool vfio_get_xlat_addr(IOMMUTLBEntry *iotlb, void **vaddr,
557                                ram_addr_t *ram_addr, bool *read_only)
558 {
559     MemoryRegion *mr;
560     hwaddr xlat;
561     hwaddr len = iotlb->addr_mask + 1;
562     bool writable = iotlb->perm & IOMMU_WO;
563 
564     /*
565      * The IOMMU TLB entry we have just covers translation through
566      * this IOMMU to its immediate target.  We need to translate
567      * it the rest of the way through to memory.
568      */
569     mr = address_space_translate(&address_space_memory,
570                                  iotlb->translated_addr,
571                                  &xlat, &len, writable,
572                                  MEMTXATTRS_UNSPECIFIED);
573     if (!memory_region_is_ram(mr)) {
574         error_report("iommu map to non memory area %"HWADDR_PRIx"",
575                      xlat);
576         return false;
577     }
578 
579     /*
580      * Translation truncates length to the IOMMU page size,
581      * check that it did not truncate too much.
582      */
583     if (len & iotlb->addr_mask) {
584         error_report("iommu has granularity incompatible with target AS");
585         return false;
586     }
587 
588     if (vaddr) {
589         *vaddr = memory_region_get_ram_ptr(mr) + xlat;
590     }
591 
592     if (ram_addr) {
593         *ram_addr = memory_region_get_ram_addr(mr) + xlat;
594     }
595 
596     if (read_only) {
597         *read_only = !writable || mr->readonly;
598     }
599 
600     return true;
601 }
602 
603 static void vfio_iommu_map_notify(IOMMUNotifier *n, IOMMUTLBEntry *iotlb)
604 {
605     VFIOGuestIOMMU *giommu = container_of(n, VFIOGuestIOMMU, n);
606     VFIOContainer *container = giommu->container;
607     hwaddr iova = iotlb->iova + giommu->iommu_offset;
608     void *vaddr;
609     int ret;
610 
611     trace_vfio_iommu_map_notify(iotlb->perm == IOMMU_NONE ? "UNMAP" : "MAP",
612                                 iova, iova + iotlb->addr_mask);
613 
614     if (iotlb->target_as != &address_space_memory) {
615         error_report("Wrong target AS \"%s\", only system memory is allowed",
616                      iotlb->target_as->name ? iotlb->target_as->name : "none");
617         return;
618     }
619 
620     rcu_read_lock();
621 
622     if ((iotlb->perm & IOMMU_RW) != IOMMU_NONE) {
623         bool read_only;
624 
625         if (!vfio_get_xlat_addr(iotlb, &vaddr, NULL, &read_only)) {
626             goto out;
627         }
628         /*
629          * vaddr is only valid until rcu_read_unlock(). But after
630          * vfio_dma_map has set up the mapping the pages will be
631          * pinned by the kernel. This makes sure that the RAM backend
632          * of vaddr will always be there, even if the memory object is
633          * destroyed and its backing memory munmap-ed.
634          */
635         ret = vfio_dma_map(container, iova,
636                            iotlb->addr_mask + 1, vaddr,
637                            read_only);
638         if (ret) {
639             error_report("vfio_dma_map(%p, 0x%"HWADDR_PRIx", "
640                          "0x%"HWADDR_PRIx", %p) = %d (%m)",
641                          container, iova,
642                          iotlb->addr_mask + 1, vaddr, ret);
643         }
644     } else {
645         ret = vfio_dma_unmap(container, iova, iotlb->addr_mask + 1, iotlb);
646         if (ret) {
647             error_report("vfio_dma_unmap(%p, 0x%"HWADDR_PRIx", "
648                          "0x%"HWADDR_PRIx") = %d (%m)",
649                          container, iova,
650                          iotlb->addr_mask + 1, ret);
651         }
652     }
653 out:
654     rcu_read_unlock();
655 }
656 
657 static void vfio_listener_region_add(MemoryListener *listener,
658                                      MemoryRegionSection *section)
659 {
660     VFIOContainer *container = container_of(listener, VFIOContainer, listener);
661     hwaddr iova, end;
662     Int128 llend, llsize;
663     void *vaddr;
664     int ret;
665     VFIOHostDMAWindow *hostwin;
666     bool hostwin_found;
667     Error *err = NULL;
668 
669     if (vfio_listener_skipped_section(section)) {
670         trace_vfio_listener_region_add_skip(
671                 section->offset_within_address_space,
672                 section->offset_within_address_space +
673                 int128_get64(int128_sub(section->size, int128_one())));
674         return;
675     }
676 
677     if (unlikely((section->offset_within_address_space & ~TARGET_PAGE_MASK) !=
678                  (section->offset_within_region & ~TARGET_PAGE_MASK))) {
679         error_report("%s received unaligned region", __func__);
680         return;
681     }
682 
683     iova = TARGET_PAGE_ALIGN(section->offset_within_address_space);
684     llend = int128_make64(section->offset_within_address_space);
685     llend = int128_add(llend, section->size);
686     llend = int128_and(llend, int128_exts64(TARGET_PAGE_MASK));
687 
688     if (int128_ge(int128_make64(iova), llend)) {
689         return;
690     }
691     end = int128_get64(int128_sub(llend, int128_one()));
692 
693     if (container->iommu_type == VFIO_SPAPR_TCE_v2_IOMMU) {
694         hwaddr pgsize = 0;
695 
696         /* For now intersections are not allowed, we may relax this later */
697         QLIST_FOREACH(hostwin, &container->hostwin_list, hostwin_next) {
698             if (ranges_overlap(hostwin->min_iova,
699                                hostwin->max_iova - hostwin->min_iova + 1,
700                                section->offset_within_address_space,
701                                int128_get64(section->size))) {
702                 error_setg(&err,
703                     "region [0x%"PRIx64",0x%"PRIx64"] overlaps with existing"
704                     "host DMA window [0x%"PRIx64",0x%"PRIx64"]",
705                     section->offset_within_address_space,
706                     section->offset_within_address_space +
707                         int128_get64(section->size) - 1,
708                     hostwin->min_iova, hostwin->max_iova);
709                 goto fail;
710             }
711         }
712 
713         ret = vfio_spapr_create_window(container, section, &pgsize);
714         if (ret) {
715             error_setg_errno(&err, -ret, "Failed to create SPAPR window");
716             goto fail;
717         }
718 
719         vfio_host_win_add(container, section->offset_within_address_space,
720                           section->offset_within_address_space +
721                           int128_get64(section->size) - 1, pgsize);
722 #ifdef CONFIG_KVM
723         if (kvm_enabled()) {
724             VFIOGroup *group;
725             IOMMUMemoryRegion *iommu_mr = IOMMU_MEMORY_REGION(section->mr);
726             struct kvm_vfio_spapr_tce param;
727             struct kvm_device_attr attr = {
728                 .group = KVM_DEV_VFIO_GROUP,
729                 .attr = KVM_DEV_VFIO_GROUP_SET_SPAPR_TCE,
730                 .addr = (uint64_t)(unsigned long)&param,
731             };
732 
733             if (!memory_region_iommu_get_attr(iommu_mr, IOMMU_ATTR_SPAPR_TCE_FD,
734                                               &param.tablefd)) {
735                 QLIST_FOREACH(group, &container->group_list, container_next) {
736                     param.groupfd = group->fd;
737                     if (ioctl(vfio_kvm_device_fd, KVM_SET_DEVICE_ATTR, &attr)) {
738                         error_report("vfio: failed to setup fd %d "
739                                      "for a group with fd %d: %s",
740                                      param.tablefd, param.groupfd,
741                                      strerror(errno));
742                         return;
743                     }
744                     trace_vfio_spapr_group_attach(param.groupfd, param.tablefd);
745                 }
746             }
747         }
748 #endif
749     }
750 
751     hostwin_found = false;
752     QLIST_FOREACH(hostwin, &container->hostwin_list, hostwin_next) {
753         if (hostwin->min_iova <= iova && end <= hostwin->max_iova) {
754             hostwin_found = true;
755             break;
756         }
757     }
758 
759     if (!hostwin_found) {
760         error_setg(&err, "Container %p can't map guest IOVA region"
761                    " 0x%"HWADDR_PRIx"..0x%"HWADDR_PRIx, container, iova, end);
762         goto fail;
763     }
764 
765     memory_region_ref(section->mr);
766 
767     if (memory_region_is_iommu(section->mr)) {
768         VFIOGuestIOMMU *giommu;
769         IOMMUMemoryRegion *iommu_mr = IOMMU_MEMORY_REGION(section->mr);
770         int iommu_idx;
771 
772         trace_vfio_listener_region_add_iommu(iova, end);
773         /*
774          * FIXME: For VFIO iommu types which have KVM acceleration to
775          * avoid bouncing all map/unmaps through qemu this way, this
776          * would be the right place to wire that up (tell the KVM
777          * device emulation the VFIO iommu handles to use).
778          */
779         giommu = g_malloc0(sizeof(*giommu));
780         giommu->iommu = iommu_mr;
781         giommu->iommu_offset = section->offset_within_address_space -
782                                section->offset_within_region;
783         giommu->container = container;
784         llend = int128_add(int128_make64(section->offset_within_region),
785                            section->size);
786         llend = int128_sub(llend, int128_one());
787         iommu_idx = memory_region_iommu_attrs_to_index(iommu_mr,
788                                                        MEMTXATTRS_UNSPECIFIED);
789         iommu_notifier_init(&giommu->n, vfio_iommu_map_notify,
790                             IOMMU_NOTIFIER_ALL,
791                             section->offset_within_region,
792                             int128_get64(llend),
793                             iommu_idx);
794 
795         ret = memory_region_iommu_set_page_size_mask(giommu->iommu,
796                                                      container->pgsizes,
797                                                      &err);
798         if (ret) {
799             g_free(giommu);
800             goto fail;
801         }
802 
803         ret = memory_region_register_iommu_notifier(section->mr, &giommu->n,
804                                                     &err);
805         if (ret) {
806             g_free(giommu);
807             goto fail;
808         }
809         QLIST_INSERT_HEAD(&container->giommu_list, giommu, giommu_next);
810         memory_region_iommu_replay(giommu->iommu, &giommu->n);
811 
812         return;
813     }
814 
815     /* Here we assume that memory_region_is_ram(section->mr)==true */
816 
817     vaddr = memory_region_get_ram_ptr(section->mr) +
818             section->offset_within_region +
819             (iova - section->offset_within_address_space);
820 
821     trace_vfio_listener_region_add_ram(iova, end, vaddr);
822 
823     llsize = int128_sub(llend, int128_make64(iova));
824 
825     if (memory_region_is_ram_device(section->mr)) {
826         hwaddr pgmask = (1ULL << ctz64(hostwin->iova_pgsizes)) - 1;
827 
828         if ((iova & pgmask) || (int128_get64(llsize) & pgmask)) {
829             trace_vfio_listener_region_add_no_dma_map(
830                 memory_region_name(section->mr),
831                 section->offset_within_address_space,
832                 int128_getlo(section->size),
833                 pgmask + 1);
834             return;
835         }
836     }
837 
838     ret = vfio_dma_map(container, iova, int128_get64(llsize),
839                        vaddr, section->readonly);
840     if (ret) {
841         error_setg(&err, "vfio_dma_map(%p, 0x%"HWADDR_PRIx", "
842                    "0x%"HWADDR_PRIx", %p) = %d (%m)",
843                    container, iova, int128_get64(llsize), vaddr, ret);
844         if (memory_region_is_ram_device(section->mr)) {
845             /* Allow unexpected mappings not to be fatal for RAM devices */
846             error_report_err(err);
847             return;
848         }
849         goto fail;
850     }
851 
852     return;
853 
854 fail:
855     if (memory_region_is_ram_device(section->mr)) {
856         error_report("failed to vfio_dma_map. pci p2p may not work");
857         return;
858     }
859     /*
860      * On the initfn path, store the first error in the container so we
861      * can gracefully fail.  Runtime, there's not much we can do other
862      * than throw a hardware error.
863      */
864     if (!container->initialized) {
865         if (!container->error) {
866             error_propagate_prepend(&container->error, err,
867                                     "Region %s: ",
868                                     memory_region_name(section->mr));
869         } else {
870             error_free(err);
871         }
872     } else {
873         error_report_err(err);
874         hw_error("vfio: DMA mapping failed, unable to continue");
875     }
876 }
877 
878 static void vfio_listener_region_del(MemoryListener *listener,
879                                      MemoryRegionSection *section)
880 {
881     VFIOContainer *container = container_of(listener, VFIOContainer, listener);
882     hwaddr iova, end;
883     Int128 llend, llsize;
884     int ret;
885     bool try_unmap = true;
886 
887     if (vfio_listener_skipped_section(section)) {
888         trace_vfio_listener_region_del_skip(
889                 section->offset_within_address_space,
890                 section->offset_within_address_space +
891                 int128_get64(int128_sub(section->size, int128_one())));
892         return;
893     }
894 
895     if (unlikely((section->offset_within_address_space & ~TARGET_PAGE_MASK) !=
896                  (section->offset_within_region & ~TARGET_PAGE_MASK))) {
897         error_report("%s received unaligned region", __func__);
898         return;
899     }
900 
901     if (memory_region_is_iommu(section->mr)) {
902         VFIOGuestIOMMU *giommu;
903 
904         QLIST_FOREACH(giommu, &container->giommu_list, giommu_next) {
905             if (MEMORY_REGION(giommu->iommu) == section->mr &&
906                 giommu->n.start == section->offset_within_region) {
907                 memory_region_unregister_iommu_notifier(section->mr,
908                                                         &giommu->n);
909                 QLIST_REMOVE(giommu, giommu_next);
910                 g_free(giommu);
911                 break;
912             }
913         }
914 
915         /*
916          * FIXME: We assume the one big unmap below is adequate to
917          * remove any individual page mappings in the IOMMU which
918          * might have been copied into VFIO. This works for a page table
919          * based IOMMU where a big unmap flattens a large range of IO-PTEs.
920          * That may not be true for all IOMMU types.
921          */
922     }
923 
924     iova = TARGET_PAGE_ALIGN(section->offset_within_address_space);
925     llend = int128_make64(section->offset_within_address_space);
926     llend = int128_add(llend, section->size);
927     llend = int128_and(llend, int128_exts64(TARGET_PAGE_MASK));
928 
929     if (int128_ge(int128_make64(iova), llend)) {
930         return;
931     }
932     end = int128_get64(int128_sub(llend, int128_one()));
933 
934     llsize = int128_sub(llend, int128_make64(iova));
935 
936     trace_vfio_listener_region_del(iova, end);
937 
938     if (memory_region_is_ram_device(section->mr)) {
939         hwaddr pgmask;
940         VFIOHostDMAWindow *hostwin;
941         bool hostwin_found = false;
942 
943         QLIST_FOREACH(hostwin, &container->hostwin_list, hostwin_next) {
944             if (hostwin->min_iova <= iova && end <= hostwin->max_iova) {
945                 hostwin_found = true;
946                 break;
947             }
948         }
949         assert(hostwin_found); /* or region_add() would have failed */
950 
951         pgmask = (1ULL << ctz64(hostwin->iova_pgsizes)) - 1;
952         try_unmap = !((iova & pgmask) || (int128_get64(llsize) & pgmask));
953     }
954 
955     if (try_unmap) {
956         if (int128_eq(llsize, int128_2_64())) {
957             /* The unmap ioctl doesn't accept a full 64-bit span. */
958             llsize = int128_rshift(llsize, 1);
959             ret = vfio_dma_unmap(container, iova, int128_get64(llsize), NULL);
960             if (ret) {
961                 error_report("vfio_dma_unmap(%p, 0x%"HWADDR_PRIx", "
962                              "0x%"HWADDR_PRIx") = %d (%m)",
963                              container, iova, int128_get64(llsize), ret);
964             }
965             iova += int128_get64(llsize);
966         }
967         ret = vfio_dma_unmap(container, iova, int128_get64(llsize), NULL);
968         if (ret) {
969             error_report("vfio_dma_unmap(%p, 0x%"HWADDR_PRIx", "
970                          "0x%"HWADDR_PRIx") = %d (%m)",
971                          container, iova, int128_get64(llsize), ret);
972         }
973     }
974 
975     memory_region_unref(section->mr);
976 
977     if (container->iommu_type == VFIO_SPAPR_TCE_v2_IOMMU) {
978         vfio_spapr_remove_window(container,
979                                  section->offset_within_address_space);
980         if (vfio_host_win_del(container,
981                               section->offset_within_address_space,
982                               section->offset_within_address_space +
983                               int128_get64(section->size) - 1) < 0) {
984             hw_error("%s: Cannot delete missing window at %"HWADDR_PRIx,
985                      __func__, section->offset_within_address_space);
986         }
987     }
988 }
989 
990 static int vfio_get_dirty_bitmap(VFIOContainer *container, uint64_t iova,
991                                  uint64_t size, ram_addr_t ram_addr)
992 {
993     struct vfio_iommu_type1_dirty_bitmap *dbitmap;
994     struct vfio_iommu_type1_dirty_bitmap_get *range;
995     uint64_t pages;
996     int ret;
997 
998     dbitmap = g_malloc0(sizeof(*dbitmap) + sizeof(*range));
999 
1000     dbitmap->argsz = sizeof(*dbitmap) + sizeof(*range);
1001     dbitmap->flags = VFIO_IOMMU_DIRTY_PAGES_FLAG_GET_BITMAP;
1002     range = (struct vfio_iommu_type1_dirty_bitmap_get *)&dbitmap->data;
1003     range->iova = iova;
1004     range->size = size;
1005 
1006     /*
1007      * cpu_physical_memory_set_dirty_lebitmap() expects pages in bitmap of
1008      * TARGET_PAGE_SIZE to mark those dirty. Hence set bitmap's pgsize to
1009      * TARGET_PAGE_SIZE.
1010      */
1011     range->bitmap.pgsize = TARGET_PAGE_SIZE;
1012 
1013     pages = TARGET_PAGE_ALIGN(range->size) >> TARGET_PAGE_BITS;
1014     range->bitmap.size = ROUND_UP(pages, sizeof(__u64) * BITS_PER_BYTE) /
1015                                          BITS_PER_BYTE;
1016     range->bitmap.data = g_try_malloc0(range->bitmap.size);
1017     if (!range->bitmap.data) {
1018         ret = -ENOMEM;
1019         goto err_out;
1020     }
1021 
1022     ret = ioctl(container->fd, VFIO_IOMMU_DIRTY_PAGES, dbitmap);
1023     if (ret) {
1024         error_report("Failed to get dirty bitmap for iova: 0x%"PRIx64
1025                 " size: 0x%"PRIx64" err: %d", (uint64_t)range->iova,
1026                 (uint64_t)range->size, errno);
1027         goto err_out;
1028     }
1029 
1030     cpu_physical_memory_set_dirty_lebitmap((unsigned long *)range->bitmap.data,
1031                                             ram_addr, pages);
1032 
1033     trace_vfio_get_dirty_bitmap(container->fd, range->iova, range->size,
1034                                 range->bitmap.size, ram_addr);
1035 err_out:
1036     g_free(range->bitmap.data);
1037     g_free(dbitmap);
1038 
1039     return ret;
1040 }
1041 
1042 typedef struct {
1043     IOMMUNotifier n;
1044     VFIOGuestIOMMU *giommu;
1045 } vfio_giommu_dirty_notifier;
1046 
1047 static void vfio_iommu_map_dirty_notify(IOMMUNotifier *n, IOMMUTLBEntry *iotlb)
1048 {
1049     vfio_giommu_dirty_notifier *gdn = container_of(n,
1050                                                 vfio_giommu_dirty_notifier, n);
1051     VFIOGuestIOMMU *giommu = gdn->giommu;
1052     VFIOContainer *container = giommu->container;
1053     hwaddr iova = iotlb->iova + giommu->iommu_offset;
1054     ram_addr_t translated_addr;
1055 
1056     trace_vfio_iommu_map_dirty_notify(iova, iova + iotlb->addr_mask);
1057 
1058     if (iotlb->target_as != &address_space_memory) {
1059         error_report("Wrong target AS \"%s\", only system memory is allowed",
1060                      iotlb->target_as->name ? iotlb->target_as->name : "none");
1061         return;
1062     }
1063 
1064     rcu_read_lock();
1065     if (vfio_get_xlat_addr(iotlb, NULL, &translated_addr, NULL)) {
1066         int ret;
1067 
1068         ret = vfio_get_dirty_bitmap(container, iova, iotlb->addr_mask + 1,
1069                                     translated_addr);
1070         if (ret) {
1071             error_report("vfio_iommu_map_dirty_notify(%p, 0x%"HWADDR_PRIx", "
1072                          "0x%"HWADDR_PRIx") = %d (%m)",
1073                          container, iova,
1074                          iotlb->addr_mask + 1, ret);
1075         }
1076     }
1077     rcu_read_unlock();
1078 }
1079 
1080 static int vfio_sync_dirty_bitmap(VFIOContainer *container,
1081                                   MemoryRegionSection *section)
1082 {
1083     ram_addr_t ram_addr;
1084 
1085     if (memory_region_is_iommu(section->mr)) {
1086         VFIOGuestIOMMU *giommu;
1087 
1088         QLIST_FOREACH(giommu, &container->giommu_list, giommu_next) {
1089             if (MEMORY_REGION(giommu->iommu) == section->mr &&
1090                 giommu->n.start == section->offset_within_region) {
1091                 Int128 llend;
1092                 vfio_giommu_dirty_notifier gdn = { .giommu = giommu };
1093                 int idx = memory_region_iommu_attrs_to_index(giommu->iommu,
1094                                                        MEMTXATTRS_UNSPECIFIED);
1095 
1096                 llend = int128_add(int128_make64(section->offset_within_region),
1097                                    section->size);
1098                 llend = int128_sub(llend, int128_one());
1099 
1100                 iommu_notifier_init(&gdn.n,
1101                                     vfio_iommu_map_dirty_notify,
1102                                     IOMMU_NOTIFIER_MAP,
1103                                     section->offset_within_region,
1104                                     int128_get64(llend),
1105                                     idx);
1106                 memory_region_iommu_replay(giommu->iommu, &gdn.n);
1107                 break;
1108             }
1109         }
1110         return 0;
1111     }
1112 
1113     ram_addr = memory_region_get_ram_addr(section->mr) +
1114                section->offset_within_region;
1115 
1116     return vfio_get_dirty_bitmap(container,
1117                        TARGET_PAGE_ALIGN(section->offset_within_address_space),
1118                        int128_get64(section->size), ram_addr);
1119 }
1120 
1121 static void vfio_listerner_log_sync(MemoryListener *listener,
1122         MemoryRegionSection *section)
1123 {
1124     VFIOContainer *container = container_of(listener, VFIOContainer, listener);
1125 
1126     if (vfio_listener_skipped_section(section) ||
1127         !container->dirty_pages_supported) {
1128         return;
1129     }
1130 
1131     if (vfio_devices_all_saving(container)) {
1132         vfio_sync_dirty_bitmap(container, section);
1133     }
1134 }
1135 
1136 static const MemoryListener vfio_memory_listener = {
1137     .region_add = vfio_listener_region_add,
1138     .region_del = vfio_listener_region_del,
1139     .log_sync = vfio_listerner_log_sync,
1140 };
1141 
1142 static void vfio_listener_release(VFIOContainer *container)
1143 {
1144     memory_listener_unregister(&container->listener);
1145     if (container->iommu_type == VFIO_SPAPR_TCE_v2_IOMMU) {
1146         memory_listener_unregister(&container->prereg_listener);
1147     }
1148 }
1149 
1150 static struct vfio_info_cap_header *
1151 vfio_get_cap(void *ptr, uint32_t cap_offset, uint16_t id)
1152 {
1153     struct vfio_info_cap_header *hdr;
1154 
1155     for (hdr = ptr + cap_offset; hdr != ptr; hdr = ptr + hdr->next) {
1156         if (hdr->id == id) {
1157             return hdr;
1158         }
1159     }
1160 
1161     return NULL;
1162 }
1163 
1164 struct vfio_info_cap_header *
1165 vfio_get_region_info_cap(struct vfio_region_info *info, uint16_t id)
1166 {
1167     if (!(info->flags & VFIO_REGION_INFO_FLAG_CAPS)) {
1168         return NULL;
1169     }
1170 
1171     return vfio_get_cap((void *)info, info->cap_offset, id);
1172 }
1173 
1174 static struct vfio_info_cap_header *
1175 vfio_get_iommu_type1_info_cap(struct vfio_iommu_type1_info *info, uint16_t id)
1176 {
1177     if (!(info->flags & VFIO_IOMMU_INFO_CAPS)) {
1178         return NULL;
1179     }
1180 
1181     return vfio_get_cap((void *)info, info->cap_offset, id);
1182 }
1183 
1184 struct vfio_info_cap_header *
1185 vfio_get_device_info_cap(struct vfio_device_info *info, uint16_t id)
1186 {
1187     if (!(info->flags & VFIO_DEVICE_FLAGS_CAPS)) {
1188         return NULL;
1189     }
1190 
1191     return vfio_get_cap((void *)info, info->cap_offset, id);
1192 }
1193 
1194 bool vfio_get_info_dma_avail(struct vfio_iommu_type1_info *info,
1195                              unsigned int *avail)
1196 {
1197     struct vfio_info_cap_header *hdr;
1198     struct vfio_iommu_type1_info_dma_avail *cap;
1199 
1200     /* If the capability cannot be found, assume no DMA limiting */
1201     hdr = vfio_get_iommu_type1_info_cap(info,
1202                                         VFIO_IOMMU_TYPE1_INFO_DMA_AVAIL);
1203     if (hdr == NULL) {
1204         return false;
1205     }
1206 
1207     if (avail != NULL) {
1208         cap = (void *) hdr;
1209         *avail = cap->avail;
1210     }
1211 
1212     return true;
1213 }
1214 
1215 static int vfio_setup_region_sparse_mmaps(VFIORegion *region,
1216                                           struct vfio_region_info *info)
1217 {
1218     struct vfio_info_cap_header *hdr;
1219     struct vfio_region_info_cap_sparse_mmap *sparse;
1220     int i, j;
1221 
1222     hdr = vfio_get_region_info_cap(info, VFIO_REGION_INFO_CAP_SPARSE_MMAP);
1223     if (!hdr) {
1224         return -ENODEV;
1225     }
1226 
1227     sparse = container_of(hdr, struct vfio_region_info_cap_sparse_mmap, header);
1228 
1229     trace_vfio_region_sparse_mmap_header(region->vbasedev->name,
1230                                          region->nr, sparse->nr_areas);
1231 
1232     region->mmaps = g_new0(VFIOMmap, sparse->nr_areas);
1233 
1234     for (i = 0, j = 0; i < sparse->nr_areas; i++) {
1235         trace_vfio_region_sparse_mmap_entry(i, sparse->areas[i].offset,
1236                                             sparse->areas[i].offset +
1237                                             sparse->areas[i].size);
1238 
1239         if (sparse->areas[i].size) {
1240             region->mmaps[j].offset = sparse->areas[i].offset;
1241             region->mmaps[j].size = sparse->areas[i].size;
1242             j++;
1243         }
1244     }
1245 
1246     region->nr_mmaps = j;
1247     region->mmaps = g_realloc(region->mmaps, j * sizeof(VFIOMmap));
1248 
1249     return 0;
1250 }
1251 
1252 int vfio_region_setup(Object *obj, VFIODevice *vbasedev, VFIORegion *region,
1253                       int index, const char *name)
1254 {
1255     struct vfio_region_info *info;
1256     int ret;
1257 
1258     ret = vfio_get_region_info(vbasedev, index, &info);
1259     if (ret) {
1260         return ret;
1261     }
1262 
1263     region->vbasedev = vbasedev;
1264     region->flags = info->flags;
1265     region->size = info->size;
1266     region->fd_offset = info->offset;
1267     region->nr = index;
1268 
1269     if (region->size) {
1270         region->mem = g_new0(MemoryRegion, 1);
1271         memory_region_init_io(region->mem, obj, &vfio_region_ops,
1272                               region, name, region->size);
1273 
1274         if (!vbasedev->no_mmap &&
1275             region->flags & VFIO_REGION_INFO_FLAG_MMAP) {
1276 
1277             ret = vfio_setup_region_sparse_mmaps(region, info);
1278 
1279             if (ret) {
1280                 region->nr_mmaps = 1;
1281                 region->mmaps = g_new0(VFIOMmap, region->nr_mmaps);
1282                 region->mmaps[0].offset = 0;
1283                 region->mmaps[0].size = region->size;
1284             }
1285         }
1286     }
1287 
1288     g_free(info);
1289 
1290     trace_vfio_region_setup(vbasedev->name, index, name,
1291                             region->flags, region->fd_offset, region->size);
1292     return 0;
1293 }
1294 
1295 static void vfio_subregion_unmap(VFIORegion *region, int index)
1296 {
1297     trace_vfio_region_unmap(memory_region_name(&region->mmaps[index].mem),
1298                             region->mmaps[index].offset,
1299                             region->mmaps[index].offset +
1300                             region->mmaps[index].size - 1);
1301     memory_region_del_subregion(region->mem, &region->mmaps[index].mem);
1302     munmap(region->mmaps[index].mmap, region->mmaps[index].size);
1303     object_unparent(OBJECT(&region->mmaps[index].mem));
1304     region->mmaps[index].mmap = NULL;
1305 }
1306 
1307 int vfio_region_mmap(VFIORegion *region)
1308 {
1309     int i, prot = 0;
1310     char *name;
1311 
1312     if (!region->mem) {
1313         return 0;
1314     }
1315 
1316     prot |= region->flags & VFIO_REGION_INFO_FLAG_READ ? PROT_READ : 0;
1317     prot |= region->flags & VFIO_REGION_INFO_FLAG_WRITE ? PROT_WRITE : 0;
1318 
1319     for (i = 0; i < region->nr_mmaps; i++) {
1320         region->mmaps[i].mmap = mmap(NULL, region->mmaps[i].size, prot,
1321                                      MAP_SHARED, region->vbasedev->fd,
1322                                      region->fd_offset +
1323                                      region->mmaps[i].offset);
1324         if (region->mmaps[i].mmap == MAP_FAILED) {
1325             int ret = -errno;
1326 
1327             trace_vfio_region_mmap_fault(memory_region_name(region->mem), i,
1328                                          region->fd_offset +
1329                                          region->mmaps[i].offset,
1330                                          region->fd_offset +
1331                                          region->mmaps[i].offset +
1332                                          region->mmaps[i].size - 1, ret);
1333 
1334             region->mmaps[i].mmap = NULL;
1335 
1336             for (i--; i >= 0; i--) {
1337                 vfio_subregion_unmap(region, i);
1338             }
1339 
1340             return ret;
1341         }
1342 
1343         name = g_strdup_printf("%s mmaps[%d]",
1344                                memory_region_name(region->mem), i);
1345         memory_region_init_ram_device_ptr(&region->mmaps[i].mem,
1346                                           memory_region_owner(region->mem),
1347                                           name, region->mmaps[i].size,
1348                                           region->mmaps[i].mmap);
1349         g_free(name);
1350         memory_region_add_subregion(region->mem, region->mmaps[i].offset,
1351                                     &region->mmaps[i].mem);
1352 
1353         trace_vfio_region_mmap(memory_region_name(&region->mmaps[i].mem),
1354                                region->mmaps[i].offset,
1355                                region->mmaps[i].offset +
1356                                region->mmaps[i].size - 1);
1357     }
1358 
1359     return 0;
1360 }
1361 
1362 void vfio_region_unmap(VFIORegion *region)
1363 {
1364     int i;
1365 
1366     if (!region->mem) {
1367         return;
1368     }
1369 
1370     for (i = 0; i < region->nr_mmaps; i++) {
1371         if (region->mmaps[i].mmap) {
1372             vfio_subregion_unmap(region, i);
1373         }
1374     }
1375 }
1376 
1377 void vfio_region_exit(VFIORegion *region)
1378 {
1379     int i;
1380 
1381     if (!region->mem) {
1382         return;
1383     }
1384 
1385     for (i = 0; i < region->nr_mmaps; i++) {
1386         if (region->mmaps[i].mmap) {
1387             memory_region_del_subregion(region->mem, &region->mmaps[i].mem);
1388         }
1389     }
1390 
1391     trace_vfio_region_exit(region->vbasedev->name, region->nr);
1392 }
1393 
1394 void vfio_region_finalize(VFIORegion *region)
1395 {
1396     int i;
1397 
1398     if (!region->mem) {
1399         return;
1400     }
1401 
1402     for (i = 0; i < region->nr_mmaps; i++) {
1403         if (region->mmaps[i].mmap) {
1404             munmap(region->mmaps[i].mmap, region->mmaps[i].size);
1405             object_unparent(OBJECT(&region->mmaps[i].mem));
1406         }
1407     }
1408 
1409     object_unparent(OBJECT(region->mem));
1410 
1411     g_free(region->mem);
1412     g_free(region->mmaps);
1413 
1414     trace_vfio_region_finalize(region->vbasedev->name, region->nr);
1415 
1416     region->mem = NULL;
1417     region->mmaps = NULL;
1418     region->nr_mmaps = 0;
1419     region->size = 0;
1420     region->flags = 0;
1421     region->nr = 0;
1422 }
1423 
1424 void vfio_region_mmaps_set_enabled(VFIORegion *region, bool enabled)
1425 {
1426     int i;
1427 
1428     if (!region->mem) {
1429         return;
1430     }
1431 
1432     for (i = 0; i < region->nr_mmaps; i++) {
1433         if (region->mmaps[i].mmap) {
1434             memory_region_set_enabled(&region->mmaps[i].mem, enabled);
1435         }
1436     }
1437 
1438     trace_vfio_region_mmaps_set_enabled(memory_region_name(region->mem),
1439                                         enabled);
1440 }
1441 
1442 void vfio_reset_handler(void *opaque)
1443 {
1444     VFIOGroup *group;
1445     VFIODevice *vbasedev;
1446 
1447     QLIST_FOREACH(group, &vfio_group_list, next) {
1448         QLIST_FOREACH(vbasedev, &group->device_list, next) {
1449             if (vbasedev->dev->realized) {
1450                 vbasedev->ops->vfio_compute_needs_reset(vbasedev);
1451             }
1452         }
1453     }
1454 
1455     QLIST_FOREACH(group, &vfio_group_list, next) {
1456         QLIST_FOREACH(vbasedev, &group->device_list, next) {
1457             if (vbasedev->dev->realized && vbasedev->needs_reset) {
1458                 vbasedev->ops->vfio_hot_reset_multi(vbasedev);
1459             }
1460         }
1461     }
1462 }
1463 
1464 static void vfio_kvm_device_add_group(VFIOGroup *group)
1465 {
1466 #ifdef CONFIG_KVM
1467     struct kvm_device_attr attr = {
1468         .group = KVM_DEV_VFIO_GROUP,
1469         .attr = KVM_DEV_VFIO_GROUP_ADD,
1470         .addr = (uint64_t)(unsigned long)&group->fd,
1471     };
1472 
1473     if (!kvm_enabled()) {
1474         return;
1475     }
1476 
1477     if (vfio_kvm_device_fd < 0) {
1478         struct kvm_create_device cd = {
1479             .type = KVM_DEV_TYPE_VFIO,
1480         };
1481 
1482         if (kvm_vm_ioctl(kvm_state, KVM_CREATE_DEVICE, &cd)) {
1483             error_report("Failed to create KVM VFIO device: %m");
1484             return;
1485         }
1486 
1487         vfio_kvm_device_fd = cd.fd;
1488     }
1489 
1490     if (ioctl(vfio_kvm_device_fd, KVM_SET_DEVICE_ATTR, &attr)) {
1491         error_report("Failed to add group %d to KVM VFIO device: %m",
1492                      group->groupid);
1493     }
1494 #endif
1495 }
1496 
1497 static void vfio_kvm_device_del_group(VFIOGroup *group)
1498 {
1499 #ifdef CONFIG_KVM
1500     struct kvm_device_attr attr = {
1501         .group = KVM_DEV_VFIO_GROUP,
1502         .attr = KVM_DEV_VFIO_GROUP_DEL,
1503         .addr = (uint64_t)(unsigned long)&group->fd,
1504     };
1505 
1506     if (vfio_kvm_device_fd < 0) {
1507         return;
1508     }
1509 
1510     if (ioctl(vfio_kvm_device_fd, KVM_SET_DEVICE_ATTR, &attr)) {
1511         error_report("Failed to remove group %d from KVM VFIO device: %m",
1512                      group->groupid);
1513     }
1514 #endif
1515 }
1516 
1517 static VFIOAddressSpace *vfio_get_address_space(AddressSpace *as)
1518 {
1519     VFIOAddressSpace *space;
1520 
1521     QLIST_FOREACH(space, &vfio_address_spaces, list) {
1522         if (space->as == as) {
1523             return space;
1524         }
1525     }
1526 
1527     /* No suitable VFIOAddressSpace, create a new one */
1528     space = g_malloc0(sizeof(*space));
1529     space->as = as;
1530     QLIST_INIT(&space->containers);
1531 
1532     QLIST_INSERT_HEAD(&vfio_address_spaces, space, list);
1533 
1534     return space;
1535 }
1536 
1537 static void vfio_put_address_space(VFIOAddressSpace *space)
1538 {
1539     if (QLIST_EMPTY(&space->containers)) {
1540         QLIST_REMOVE(space, list);
1541         g_free(space);
1542     }
1543 }
1544 
1545 /*
1546  * vfio_get_iommu_type - selects the richest iommu_type (v2 first)
1547  */
1548 static int vfio_get_iommu_type(VFIOContainer *container,
1549                                Error **errp)
1550 {
1551     int iommu_types[] = { VFIO_TYPE1v2_IOMMU, VFIO_TYPE1_IOMMU,
1552                           VFIO_SPAPR_TCE_v2_IOMMU, VFIO_SPAPR_TCE_IOMMU };
1553     int i;
1554 
1555     for (i = 0; i < ARRAY_SIZE(iommu_types); i++) {
1556         if (ioctl(container->fd, VFIO_CHECK_EXTENSION, iommu_types[i])) {
1557             return iommu_types[i];
1558         }
1559     }
1560     error_setg(errp, "No available IOMMU models");
1561     return -EINVAL;
1562 }
1563 
1564 static int vfio_init_container(VFIOContainer *container, int group_fd,
1565                                Error **errp)
1566 {
1567     int iommu_type, ret;
1568 
1569     iommu_type = vfio_get_iommu_type(container, errp);
1570     if (iommu_type < 0) {
1571         return iommu_type;
1572     }
1573 
1574     ret = ioctl(group_fd, VFIO_GROUP_SET_CONTAINER, &container->fd);
1575     if (ret) {
1576         error_setg_errno(errp, errno, "Failed to set group container");
1577         return -errno;
1578     }
1579 
1580     while (ioctl(container->fd, VFIO_SET_IOMMU, iommu_type)) {
1581         if (iommu_type == VFIO_SPAPR_TCE_v2_IOMMU) {
1582             /*
1583              * On sPAPR, despite the IOMMU subdriver always advertises v1 and
1584              * v2, the running platform may not support v2 and there is no
1585              * way to guess it until an IOMMU group gets added to the container.
1586              * So in case it fails with v2, try v1 as a fallback.
1587              */
1588             iommu_type = VFIO_SPAPR_TCE_IOMMU;
1589             continue;
1590         }
1591         error_setg_errno(errp, errno, "Failed to set iommu for container");
1592         return -errno;
1593     }
1594 
1595     container->iommu_type = iommu_type;
1596     return 0;
1597 }
1598 
1599 static int vfio_get_iommu_info(VFIOContainer *container,
1600                                struct vfio_iommu_type1_info **info)
1601 {
1602 
1603     size_t argsz = sizeof(struct vfio_iommu_type1_info);
1604 
1605     *info = g_new0(struct vfio_iommu_type1_info, 1);
1606 again:
1607     (*info)->argsz = argsz;
1608 
1609     if (ioctl(container->fd, VFIO_IOMMU_GET_INFO, *info)) {
1610         g_free(*info);
1611         *info = NULL;
1612         return -errno;
1613     }
1614 
1615     if (((*info)->argsz > argsz)) {
1616         argsz = (*info)->argsz;
1617         *info = g_realloc(*info, argsz);
1618         goto again;
1619     }
1620 
1621     return 0;
1622 }
1623 
1624 static struct vfio_info_cap_header *
1625 vfio_get_iommu_info_cap(struct vfio_iommu_type1_info *info, uint16_t id)
1626 {
1627     struct vfio_info_cap_header *hdr;
1628     void *ptr = info;
1629 
1630     if (!(info->flags & VFIO_IOMMU_INFO_CAPS)) {
1631         return NULL;
1632     }
1633 
1634     for (hdr = ptr + info->cap_offset; hdr != ptr; hdr = ptr + hdr->next) {
1635         if (hdr->id == id) {
1636             return hdr;
1637         }
1638     }
1639 
1640     return NULL;
1641 }
1642 
1643 static void vfio_get_iommu_info_migration(VFIOContainer *container,
1644                                          struct vfio_iommu_type1_info *info)
1645 {
1646     struct vfio_info_cap_header *hdr;
1647     struct vfio_iommu_type1_info_cap_migration *cap_mig;
1648 
1649     hdr = vfio_get_iommu_info_cap(info, VFIO_IOMMU_TYPE1_INFO_CAP_MIGRATION);
1650     if (!hdr) {
1651         return;
1652     }
1653 
1654     cap_mig = container_of(hdr, struct vfio_iommu_type1_info_cap_migration,
1655                             header);
1656 
1657     /*
1658      * cpu_physical_memory_set_dirty_lebitmap() expects pages in bitmap of
1659      * TARGET_PAGE_SIZE to mark those dirty.
1660      */
1661     if (cap_mig->pgsize_bitmap & TARGET_PAGE_SIZE) {
1662         container->dirty_pages_supported = true;
1663         container->max_dirty_bitmap_size = cap_mig->max_dirty_bitmap_size;
1664         container->dirty_pgsizes = cap_mig->pgsize_bitmap;
1665     }
1666 }
1667 
1668 static int vfio_connect_container(VFIOGroup *group, AddressSpace *as,
1669                                   Error **errp)
1670 {
1671     VFIOContainer *container;
1672     int ret, fd;
1673     VFIOAddressSpace *space;
1674 
1675     space = vfio_get_address_space(as);
1676 
1677     /*
1678      * VFIO is currently incompatible with discarding of RAM insofar as the
1679      * madvise to purge (zap) the page from QEMU's address space does not
1680      * interact with the memory API and therefore leaves stale virtual to
1681      * physical mappings in the IOMMU if the page was previously pinned.  We
1682      * therefore set discarding broken for each group added to a container,
1683      * whether the container is used individually or shared.  This provides
1684      * us with options to allow devices within a group to opt-in and allow
1685      * discarding, so long as it is done consistently for a group (for instance
1686      * if the device is an mdev device where it is known that the host vendor
1687      * driver will never pin pages outside of the working set of the guest
1688      * driver, which would thus not be discarding candidates).
1689      *
1690      * The first opportunity to induce pinning occurs here where we attempt to
1691      * attach the group to existing containers within the AddressSpace.  If any
1692      * pages are already zapped from the virtual address space, such as from
1693      * previous discards, new pinning will cause valid mappings to be
1694      * re-established.  Likewise, when the overall MemoryListener for a new
1695      * container is registered, a replay of mappings within the AddressSpace
1696      * will occur, re-establishing any previously zapped pages as well.
1697      *
1698      * Especially virtio-balloon is currently only prevented from discarding
1699      * new memory, it will not yet set ram_block_discard_set_required() and
1700      * therefore, neither stops us here or deals with the sudden memory
1701      * consumption of inflated memory.
1702      */
1703     ret = ram_block_discard_disable(true);
1704     if (ret) {
1705         error_setg_errno(errp, -ret, "Cannot set discarding of RAM broken");
1706         return ret;
1707     }
1708 
1709     QLIST_FOREACH(container, &space->containers, next) {
1710         if (!ioctl(group->fd, VFIO_GROUP_SET_CONTAINER, &container->fd)) {
1711             group->container = container;
1712             QLIST_INSERT_HEAD(&container->group_list, group, container_next);
1713             vfio_kvm_device_add_group(group);
1714             return 0;
1715         }
1716     }
1717 
1718     fd = qemu_open_old("/dev/vfio/vfio", O_RDWR);
1719     if (fd < 0) {
1720         error_setg_errno(errp, errno, "failed to open /dev/vfio/vfio");
1721         ret = -errno;
1722         goto put_space_exit;
1723     }
1724 
1725     ret = ioctl(fd, VFIO_GET_API_VERSION);
1726     if (ret != VFIO_API_VERSION) {
1727         error_setg(errp, "supported vfio version: %d, "
1728                    "reported version: %d", VFIO_API_VERSION, ret);
1729         ret = -EINVAL;
1730         goto close_fd_exit;
1731     }
1732 
1733     container = g_malloc0(sizeof(*container));
1734     container->space = space;
1735     container->fd = fd;
1736     container->error = NULL;
1737     container->dirty_pages_supported = false;
1738     QLIST_INIT(&container->giommu_list);
1739     QLIST_INIT(&container->hostwin_list);
1740 
1741     ret = vfio_init_container(container, group->fd, errp);
1742     if (ret) {
1743         goto free_container_exit;
1744     }
1745 
1746     switch (container->iommu_type) {
1747     case VFIO_TYPE1v2_IOMMU:
1748     case VFIO_TYPE1_IOMMU:
1749     {
1750         struct vfio_iommu_type1_info *info;
1751 
1752         /*
1753          * FIXME: This assumes that a Type1 IOMMU can map any 64-bit
1754          * IOVA whatsoever.  That's not actually true, but the current
1755          * kernel interface doesn't tell us what it can map, and the
1756          * existing Type1 IOMMUs generally support any IOVA we're
1757          * going to actually try in practice.
1758          */
1759         ret = vfio_get_iommu_info(container, &info);
1760 
1761         if (ret || !(info->flags & VFIO_IOMMU_INFO_PGSIZES)) {
1762             /* Assume 4k IOVA page size */
1763             info->iova_pgsizes = 4096;
1764         }
1765         vfio_host_win_add(container, 0, (hwaddr)-1, info->iova_pgsizes);
1766         container->pgsizes = info->iova_pgsizes;
1767 
1768         if (!ret) {
1769             vfio_get_iommu_info_migration(container, info);
1770         }
1771         g_free(info);
1772         break;
1773     }
1774     case VFIO_SPAPR_TCE_v2_IOMMU:
1775     case VFIO_SPAPR_TCE_IOMMU:
1776     {
1777         struct vfio_iommu_spapr_tce_info info;
1778         bool v2 = container->iommu_type == VFIO_SPAPR_TCE_v2_IOMMU;
1779 
1780         /*
1781          * The host kernel code implementing VFIO_IOMMU_DISABLE is called
1782          * when container fd is closed so we do not call it explicitly
1783          * in this file.
1784          */
1785         if (!v2) {
1786             ret = ioctl(fd, VFIO_IOMMU_ENABLE);
1787             if (ret) {
1788                 error_setg_errno(errp, errno, "failed to enable container");
1789                 ret = -errno;
1790                 goto free_container_exit;
1791             }
1792         } else {
1793             container->prereg_listener = vfio_prereg_listener;
1794 
1795             memory_listener_register(&container->prereg_listener,
1796                                      &address_space_memory);
1797             if (container->error) {
1798                 memory_listener_unregister(&container->prereg_listener);
1799                 ret = -1;
1800                 error_propagate_prepend(errp, container->error,
1801                     "RAM memory listener initialization failed: ");
1802                 goto free_container_exit;
1803             }
1804         }
1805 
1806         info.argsz = sizeof(info);
1807         ret = ioctl(fd, VFIO_IOMMU_SPAPR_TCE_GET_INFO, &info);
1808         if (ret) {
1809             error_setg_errno(errp, errno,
1810                              "VFIO_IOMMU_SPAPR_TCE_GET_INFO failed");
1811             ret = -errno;
1812             if (v2) {
1813                 memory_listener_unregister(&container->prereg_listener);
1814             }
1815             goto free_container_exit;
1816         }
1817 
1818         if (v2) {
1819             container->pgsizes = info.ddw.pgsizes;
1820             /*
1821              * There is a default window in just created container.
1822              * To make region_add/del simpler, we better remove this
1823              * window now and let those iommu_listener callbacks
1824              * create/remove them when needed.
1825              */
1826             ret = vfio_spapr_remove_window(container, info.dma32_window_start);
1827             if (ret) {
1828                 error_setg_errno(errp, -ret,
1829                                  "failed to remove existing window");
1830                 goto free_container_exit;
1831             }
1832         } else {
1833             /* The default table uses 4K pages */
1834             container->pgsizes = 0x1000;
1835             vfio_host_win_add(container, info.dma32_window_start,
1836                               info.dma32_window_start +
1837                               info.dma32_window_size - 1,
1838                               0x1000);
1839         }
1840     }
1841     }
1842 
1843     vfio_kvm_device_add_group(group);
1844 
1845     QLIST_INIT(&container->group_list);
1846     QLIST_INSERT_HEAD(&space->containers, container, next);
1847 
1848     group->container = container;
1849     QLIST_INSERT_HEAD(&container->group_list, group, container_next);
1850 
1851     container->listener = vfio_memory_listener;
1852 
1853     memory_listener_register(&container->listener, container->space->as);
1854 
1855     if (container->error) {
1856         ret = -1;
1857         error_propagate_prepend(errp, container->error,
1858             "memory listener initialization failed: ");
1859         goto listener_release_exit;
1860     }
1861 
1862     container->initialized = true;
1863 
1864     return 0;
1865 listener_release_exit:
1866     QLIST_REMOVE(group, container_next);
1867     QLIST_REMOVE(container, next);
1868     vfio_kvm_device_del_group(group);
1869     vfio_listener_release(container);
1870 
1871 free_container_exit:
1872     g_free(container);
1873 
1874 close_fd_exit:
1875     close(fd);
1876 
1877 put_space_exit:
1878     ram_block_discard_disable(false);
1879     vfio_put_address_space(space);
1880 
1881     return ret;
1882 }
1883 
1884 static void vfio_disconnect_container(VFIOGroup *group)
1885 {
1886     VFIOContainer *container = group->container;
1887 
1888     QLIST_REMOVE(group, container_next);
1889     group->container = NULL;
1890 
1891     /*
1892      * Explicitly release the listener first before unset container,
1893      * since unset may destroy the backend container if it's the last
1894      * group.
1895      */
1896     if (QLIST_EMPTY(&container->group_list)) {
1897         vfio_listener_release(container);
1898     }
1899 
1900     if (ioctl(group->fd, VFIO_GROUP_UNSET_CONTAINER, &container->fd)) {
1901         error_report("vfio: error disconnecting group %d from container",
1902                      group->groupid);
1903     }
1904 
1905     if (QLIST_EMPTY(&container->group_list)) {
1906         VFIOAddressSpace *space = container->space;
1907         VFIOGuestIOMMU *giommu, *tmp;
1908 
1909         QLIST_REMOVE(container, next);
1910 
1911         QLIST_FOREACH_SAFE(giommu, &container->giommu_list, giommu_next, tmp) {
1912             memory_region_unregister_iommu_notifier(
1913                     MEMORY_REGION(giommu->iommu), &giommu->n);
1914             QLIST_REMOVE(giommu, giommu_next);
1915             g_free(giommu);
1916         }
1917 
1918         trace_vfio_disconnect_container(container->fd);
1919         close(container->fd);
1920         g_free(container);
1921 
1922         vfio_put_address_space(space);
1923     }
1924 }
1925 
1926 VFIOGroup *vfio_get_group(int groupid, AddressSpace *as, Error **errp)
1927 {
1928     VFIOGroup *group;
1929     char path[32];
1930     struct vfio_group_status status = { .argsz = sizeof(status) };
1931 
1932     QLIST_FOREACH(group, &vfio_group_list, next) {
1933         if (group->groupid == groupid) {
1934             /* Found it.  Now is it already in the right context? */
1935             if (group->container->space->as == as) {
1936                 return group;
1937             } else {
1938                 error_setg(errp, "group %d used in multiple address spaces",
1939                            group->groupid);
1940                 return NULL;
1941             }
1942         }
1943     }
1944 
1945     group = g_malloc0(sizeof(*group));
1946 
1947     snprintf(path, sizeof(path), "/dev/vfio/%d", groupid);
1948     group->fd = qemu_open_old(path, O_RDWR);
1949     if (group->fd < 0) {
1950         error_setg_errno(errp, errno, "failed to open %s", path);
1951         goto free_group_exit;
1952     }
1953 
1954     if (ioctl(group->fd, VFIO_GROUP_GET_STATUS, &status)) {
1955         error_setg_errno(errp, errno, "failed to get group %d status", groupid);
1956         goto close_fd_exit;
1957     }
1958 
1959     if (!(status.flags & VFIO_GROUP_FLAGS_VIABLE)) {
1960         error_setg(errp, "group %d is not viable", groupid);
1961         error_append_hint(errp,
1962                           "Please ensure all devices within the iommu_group "
1963                           "are bound to their vfio bus driver.\n");
1964         goto close_fd_exit;
1965     }
1966 
1967     group->groupid = groupid;
1968     QLIST_INIT(&group->device_list);
1969 
1970     if (vfio_connect_container(group, as, errp)) {
1971         error_prepend(errp, "failed to setup container for group %d: ",
1972                       groupid);
1973         goto close_fd_exit;
1974     }
1975 
1976     if (QLIST_EMPTY(&vfio_group_list)) {
1977         qemu_register_reset(vfio_reset_handler, NULL);
1978     }
1979 
1980     QLIST_INSERT_HEAD(&vfio_group_list, group, next);
1981 
1982     return group;
1983 
1984 close_fd_exit:
1985     close(group->fd);
1986 
1987 free_group_exit:
1988     g_free(group);
1989 
1990     return NULL;
1991 }
1992 
1993 void vfio_put_group(VFIOGroup *group)
1994 {
1995     if (!group || !QLIST_EMPTY(&group->device_list)) {
1996         return;
1997     }
1998 
1999     if (!group->ram_block_discard_allowed) {
2000         ram_block_discard_disable(false);
2001     }
2002     vfio_kvm_device_del_group(group);
2003     vfio_disconnect_container(group);
2004     QLIST_REMOVE(group, next);
2005     trace_vfio_put_group(group->fd);
2006     close(group->fd);
2007     g_free(group);
2008 
2009     if (QLIST_EMPTY(&vfio_group_list)) {
2010         qemu_unregister_reset(vfio_reset_handler, NULL);
2011     }
2012 }
2013 
2014 int vfio_get_device(VFIOGroup *group, const char *name,
2015                     VFIODevice *vbasedev, Error **errp)
2016 {
2017     struct vfio_device_info dev_info = { .argsz = sizeof(dev_info) };
2018     int ret, fd;
2019 
2020     fd = ioctl(group->fd, VFIO_GROUP_GET_DEVICE_FD, name);
2021     if (fd < 0) {
2022         error_setg_errno(errp, errno, "error getting device from group %d",
2023                          group->groupid);
2024         error_append_hint(errp,
2025                       "Verify all devices in group %d are bound to vfio-<bus> "
2026                       "or pci-stub and not already in use\n", group->groupid);
2027         return fd;
2028     }
2029 
2030     ret = ioctl(fd, VFIO_DEVICE_GET_INFO, &dev_info);
2031     if (ret) {
2032         error_setg_errno(errp, errno, "error getting device info");
2033         close(fd);
2034         return ret;
2035     }
2036 
2037     /*
2038      * Set discarding of RAM as not broken for this group if the driver knows
2039      * the device operates compatibly with discarding.  Setting must be
2040      * consistent per group, but since compatibility is really only possible
2041      * with mdev currently, we expect singleton groups.
2042      */
2043     if (vbasedev->ram_block_discard_allowed !=
2044         group->ram_block_discard_allowed) {
2045         if (!QLIST_EMPTY(&group->device_list)) {
2046             error_setg(errp, "Inconsistent setting of support for discarding "
2047                        "RAM (e.g., balloon) within group");
2048             close(fd);
2049             return -1;
2050         }
2051 
2052         if (!group->ram_block_discard_allowed) {
2053             group->ram_block_discard_allowed = true;
2054             ram_block_discard_disable(false);
2055         }
2056     }
2057 
2058     vbasedev->fd = fd;
2059     vbasedev->group = group;
2060     QLIST_INSERT_HEAD(&group->device_list, vbasedev, next);
2061 
2062     vbasedev->num_irqs = dev_info.num_irqs;
2063     vbasedev->num_regions = dev_info.num_regions;
2064     vbasedev->flags = dev_info.flags;
2065 
2066     trace_vfio_get_device(name, dev_info.flags, dev_info.num_regions,
2067                           dev_info.num_irqs);
2068 
2069     vbasedev->reset_works = !!(dev_info.flags & VFIO_DEVICE_FLAGS_RESET);
2070     return 0;
2071 }
2072 
2073 void vfio_put_base_device(VFIODevice *vbasedev)
2074 {
2075     if (!vbasedev->group) {
2076         return;
2077     }
2078     QLIST_REMOVE(vbasedev, next);
2079     vbasedev->group = NULL;
2080     trace_vfio_put_base_device(vbasedev->fd);
2081     close(vbasedev->fd);
2082 }
2083 
2084 int vfio_get_region_info(VFIODevice *vbasedev, int index,
2085                          struct vfio_region_info **info)
2086 {
2087     size_t argsz = sizeof(struct vfio_region_info);
2088 
2089     *info = g_malloc0(argsz);
2090 
2091     (*info)->index = index;
2092 retry:
2093     (*info)->argsz = argsz;
2094 
2095     if (ioctl(vbasedev->fd, VFIO_DEVICE_GET_REGION_INFO, *info)) {
2096         g_free(*info);
2097         *info = NULL;
2098         return -errno;
2099     }
2100 
2101     if ((*info)->argsz > argsz) {
2102         argsz = (*info)->argsz;
2103         *info = g_realloc(*info, argsz);
2104 
2105         goto retry;
2106     }
2107 
2108     return 0;
2109 }
2110 
2111 int vfio_get_dev_region_info(VFIODevice *vbasedev, uint32_t type,
2112                              uint32_t subtype, struct vfio_region_info **info)
2113 {
2114     int i;
2115 
2116     for (i = 0; i < vbasedev->num_regions; i++) {
2117         struct vfio_info_cap_header *hdr;
2118         struct vfio_region_info_cap_type *cap_type;
2119 
2120         if (vfio_get_region_info(vbasedev, i, info)) {
2121             continue;
2122         }
2123 
2124         hdr = vfio_get_region_info_cap(*info, VFIO_REGION_INFO_CAP_TYPE);
2125         if (!hdr) {
2126             g_free(*info);
2127             continue;
2128         }
2129 
2130         cap_type = container_of(hdr, struct vfio_region_info_cap_type, header);
2131 
2132         trace_vfio_get_dev_region(vbasedev->name, i,
2133                                   cap_type->type, cap_type->subtype);
2134 
2135         if (cap_type->type == type && cap_type->subtype == subtype) {
2136             return 0;
2137         }
2138 
2139         g_free(*info);
2140     }
2141 
2142     *info = NULL;
2143     return -ENODEV;
2144 }
2145 
2146 bool vfio_has_region_cap(VFIODevice *vbasedev, int region, uint16_t cap_type)
2147 {
2148     struct vfio_region_info *info = NULL;
2149     bool ret = false;
2150 
2151     if (!vfio_get_region_info(vbasedev, region, &info)) {
2152         if (vfio_get_region_info_cap(info, cap_type)) {
2153             ret = true;
2154         }
2155         g_free(info);
2156     }
2157 
2158     return ret;
2159 }
2160 
2161 /*
2162  * Interfaces for IBM EEH (Enhanced Error Handling)
2163  */
2164 static bool vfio_eeh_container_ok(VFIOContainer *container)
2165 {
2166     /*
2167      * As of 2016-03-04 (linux-4.5) the host kernel EEH/VFIO
2168      * implementation is broken if there are multiple groups in a
2169      * container.  The hardware works in units of Partitionable
2170      * Endpoints (== IOMMU groups) and the EEH operations naively
2171      * iterate across all groups in the container, without any logic
2172      * to make sure the groups have their state synchronized.  For
2173      * certain operations (ENABLE) that might be ok, until an error
2174      * occurs, but for others (GET_STATE) it's clearly broken.
2175      */
2176 
2177     /*
2178      * XXX Once fixed kernels exist, test for them here
2179      */
2180 
2181     if (QLIST_EMPTY(&container->group_list)) {
2182         return false;
2183     }
2184 
2185     if (QLIST_NEXT(QLIST_FIRST(&container->group_list), container_next)) {
2186         return false;
2187     }
2188 
2189     return true;
2190 }
2191 
2192 static int vfio_eeh_container_op(VFIOContainer *container, uint32_t op)
2193 {
2194     struct vfio_eeh_pe_op pe_op = {
2195         .argsz = sizeof(pe_op),
2196         .op = op,
2197     };
2198     int ret;
2199 
2200     if (!vfio_eeh_container_ok(container)) {
2201         error_report("vfio/eeh: EEH_PE_OP 0x%x: "
2202                      "kernel requires a container with exactly one group", op);
2203         return -EPERM;
2204     }
2205 
2206     ret = ioctl(container->fd, VFIO_EEH_PE_OP, &pe_op);
2207     if (ret < 0) {
2208         error_report("vfio/eeh: EEH_PE_OP 0x%x failed: %m", op);
2209         return -errno;
2210     }
2211 
2212     return ret;
2213 }
2214 
2215 static VFIOContainer *vfio_eeh_as_container(AddressSpace *as)
2216 {
2217     VFIOAddressSpace *space = vfio_get_address_space(as);
2218     VFIOContainer *container = NULL;
2219 
2220     if (QLIST_EMPTY(&space->containers)) {
2221         /* No containers to act on */
2222         goto out;
2223     }
2224 
2225     container = QLIST_FIRST(&space->containers);
2226 
2227     if (QLIST_NEXT(container, next)) {
2228         /* We don't yet have logic to synchronize EEH state across
2229          * multiple containers */
2230         container = NULL;
2231         goto out;
2232     }
2233 
2234 out:
2235     vfio_put_address_space(space);
2236     return container;
2237 }
2238 
2239 bool vfio_eeh_as_ok(AddressSpace *as)
2240 {
2241     VFIOContainer *container = vfio_eeh_as_container(as);
2242 
2243     return (container != NULL) && vfio_eeh_container_ok(container);
2244 }
2245 
2246 int vfio_eeh_as_op(AddressSpace *as, uint32_t op)
2247 {
2248     VFIOContainer *container = vfio_eeh_as_container(as);
2249 
2250     if (!container) {
2251         return -ENODEV;
2252     }
2253     return vfio_eeh_container_op(container, op);
2254 }
2255