xref: /openbmc/qemu/hw/vfio/common.c (revision 77d361b1)
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 "hw/hw.h"
33 #include "qemu/error-report.h"
34 #include "qemu/range.h"
35 #include "sysemu/kvm.h"
36 #include "trace.h"
37 #include "qapi/error.h"
38 
39 struct vfio_group_head vfio_group_list =
40     QLIST_HEAD_INITIALIZER(vfio_group_list);
41 struct vfio_as_head vfio_address_spaces =
42     QLIST_HEAD_INITIALIZER(vfio_address_spaces);
43 
44 #ifdef CONFIG_KVM
45 /*
46  * We have a single VFIO pseudo device per KVM VM.  Once created it lives
47  * for the life of the VM.  Closing the file descriptor only drops our
48  * reference to it and the device's reference to kvm.  Therefore once
49  * initialized, this file descriptor is only released on QEMU exit and
50  * we'll re-use it should another vfio device be attached before then.
51  */
52 static int vfio_kvm_device_fd = -1;
53 #endif
54 
55 /*
56  * Common VFIO interrupt disable
57  */
58 void vfio_disable_irqindex(VFIODevice *vbasedev, int index)
59 {
60     struct vfio_irq_set irq_set = {
61         .argsz = sizeof(irq_set),
62         .flags = VFIO_IRQ_SET_DATA_NONE | VFIO_IRQ_SET_ACTION_TRIGGER,
63         .index = index,
64         .start = 0,
65         .count = 0,
66     };
67 
68     ioctl(vbasedev->fd, VFIO_DEVICE_SET_IRQS, &irq_set);
69 }
70 
71 void vfio_unmask_single_irqindex(VFIODevice *vbasedev, int index)
72 {
73     struct vfio_irq_set irq_set = {
74         .argsz = sizeof(irq_set),
75         .flags = VFIO_IRQ_SET_DATA_NONE | VFIO_IRQ_SET_ACTION_UNMASK,
76         .index = index,
77         .start = 0,
78         .count = 1,
79     };
80 
81     ioctl(vbasedev->fd, VFIO_DEVICE_SET_IRQS, &irq_set);
82 }
83 
84 void vfio_mask_single_irqindex(VFIODevice *vbasedev, int index)
85 {
86     struct vfio_irq_set irq_set = {
87         .argsz = sizeof(irq_set),
88         .flags = VFIO_IRQ_SET_DATA_NONE | VFIO_IRQ_SET_ACTION_MASK,
89         .index = index,
90         .start = 0,
91         .count = 1,
92     };
93 
94     ioctl(vbasedev->fd, VFIO_DEVICE_SET_IRQS, &irq_set);
95 }
96 
97 /*
98  * IO Port/MMIO - Beware of the endians, VFIO is always little endian
99  */
100 void vfio_region_write(void *opaque, hwaddr addr,
101                        uint64_t data, unsigned size)
102 {
103     VFIORegion *region = opaque;
104     VFIODevice *vbasedev = region->vbasedev;
105     union {
106         uint8_t byte;
107         uint16_t word;
108         uint32_t dword;
109         uint64_t qword;
110     } buf;
111 
112     switch (size) {
113     case 1:
114         buf.byte = data;
115         break;
116     case 2:
117         buf.word = cpu_to_le16(data);
118         break;
119     case 4:
120         buf.dword = cpu_to_le32(data);
121         break;
122     case 8:
123         buf.qword = cpu_to_le64(data);
124         break;
125     default:
126         hw_error("vfio: unsupported write size, %d bytes", size);
127         break;
128     }
129 
130     if (pwrite(vbasedev->fd, &buf, size, region->fd_offset + addr) != size) {
131         error_report("%s(%s:region%d+0x%"HWADDR_PRIx", 0x%"PRIx64
132                      ",%d) failed: %m",
133                      __func__, vbasedev->name, region->nr,
134                      addr, data, size);
135     }
136 
137     trace_vfio_region_write(vbasedev->name, region->nr, addr, data, size);
138 
139     /*
140      * A read or write to a BAR always signals an INTx EOI.  This will
141      * do nothing if not pending (including not in INTx mode).  We assume
142      * that a BAR access is in response to an interrupt and that BAR
143      * accesses will service the interrupt.  Unfortunately, we don't know
144      * which access will service the interrupt, so we're potentially
145      * getting quite a few host interrupts per guest interrupt.
146      */
147     vbasedev->ops->vfio_eoi(vbasedev);
148 }
149 
150 uint64_t vfio_region_read(void *opaque,
151                           hwaddr addr, unsigned size)
152 {
153     VFIORegion *region = opaque;
154     VFIODevice *vbasedev = region->vbasedev;
155     union {
156         uint8_t byte;
157         uint16_t word;
158         uint32_t dword;
159         uint64_t qword;
160     } buf;
161     uint64_t data = 0;
162 
163     if (pread(vbasedev->fd, &buf, size, region->fd_offset + addr) != size) {
164         error_report("%s(%s:region%d+0x%"HWADDR_PRIx", %d) failed: %m",
165                      __func__, vbasedev->name, region->nr,
166                      addr, size);
167         return (uint64_t)-1;
168     }
169     switch (size) {
170     case 1:
171         data = buf.byte;
172         break;
173     case 2:
174         data = le16_to_cpu(buf.word);
175         break;
176     case 4:
177         data = le32_to_cpu(buf.dword);
178         break;
179     case 8:
180         data = le64_to_cpu(buf.qword);
181         break;
182     default:
183         hw_error("vfio: unsupported read size, %d bytes", size);
184         break;
185     }
186 
187     trace_vfio_region_read(vbasedev->name, region->nr, addr, size, data);
188 
189     /* Same as write above */
190     vbasedev->ops->vfio_eoi(vbasedev);
191 
192     return data;
193 }
194 
195 const MemoryRegionOps vfio_region_ops = {
196     .read = vfio_region_read,
197     .write = vfio_region_write,
198     .endianness = DEVICE_LITTLE_ENDIAN,
199     .valid = {
200         .min_access_size = 1,
201         .max_access_size = 8,
202     },
203     .impl = {
204         .min_access_size = 1,
205         .max_access_size = 8,
206     },
207 };
208 
209 /*
210  * DMA - Mapping and unmapping for the "type1" IOMMU interface used on x86
211  */
212 static int vfio_dma_unmap(VFIOContainer *container,
213                           hwaddr iova, ram_addr_t size)
214 {
215     struct vfio_iommu_type1_dma_unmap unmap = {
216         .argsz = sizeof(unmap),
217         .flags = 0,
218         .iova = iova,
219         .size = size,
220     };
221 
222     if (ioctl(container->fd, VFIO_IOMMU_UNMAP_DMA, &unmap)) {
223         error_report("VFIO_UNMAP_DMA: %d", -errno);
224         return -errno;
225     }
226 
227     return 0;
228 }
229 
230 static int vfio_dma_map(VFIOContainer *container, hwaddr iova,
231                         ram_addr_t size, void *vaddr, bool readonly)
232 {
233     struct vfio_iommu_type1_dma_map map = {
234         .argsz = sizeof(map),
235         .flags = VFIO_DMA_MAP_FLAG_READ,
236         .vaddr = (__u64)(uintptr_t)vaddr,
237         .iova = iova,
238         .size = size,
239     };
240 
241     if (!readonly) {
242         map.flags |= VFIO_DMA_MAP_FLAG_WRITE;
243     }
244 
245     /*
246      * Try the mapping, if it fails with EBUSY, unmap the region and try
247      * again.  This shouldn't be necessary, but we sometimes see it in
248      * the VGA ROM space.
249      */
250     if (ioctl(container->fd, VFIO_IOMMU_MAP_DMA, &map) == 0 ||
251         (errno == EBUSY && vfio_dma_unmap(container, iova, size) == 0 &&
252          ioctl(container->fd, VFIO_IOMMU_MAP_DMA, &map) == 0)) {
253         return 0;
254     }
255 
256     error_report("VFIO_MAP_DMA: %d", -errno);
257     return -errno;
258 }
259 
260 static void vfio_host_win_add(VFIOContainer *container,
261                               hwaddr min_iova, hwaddr max_iova,
262                               uint64_t iova_pgsizes)
263 {
264     VFIOHostDMAWindow *hostwin;
265 
266     QLIST_FOREACH(hostwin, &container->hostwin_list, hostwin_next) {
267         if (ranges_overlap(hostwin->min_iova,
268                            hostwin->max_iova - hostwin->min_iova + 1,
269                            min_iova,
270                            max_iova - min_iova + 1)) {
271             hw_error("%s: Overlapped IOMMU are not enabled", __func__);
272         }
273     }
274 
275     hostwin = g_malloc0(sizeof(*hostwin));
276 
277     hostwin->min_iova = min_iova;
278     hostwin->max_iova = max_iova;
279     hostwin->iova_pgsizes = iova_pgsizes;
280     QLIST_INSERT_HEAD(&container->hostwin_list, hostwin, hostwin_next);
281 }
282 
283 static int vfio_host_win_del(VFIOContainer *container, hwaddr min_iova,
284                              hwaddr max_iova)
285 {
286     VFIOHostDMAWindow *hostwin;
287 
288     QLIST_FOREACH(hostwin, &container->hostwin_list, hostwin_next) {
289         if (hostwin->min_iova == min_iova && hostwin->max_iova == max_iova) {
290             QLIST_REMOVE(hostwin, hostwin_next);
291             return 0;
292         }
293     }
294 
295     return -1;
296 }
297 
298 static bool vfio_listener_skipped_section(MemoryRegionSection *section)
299 {
300     return (!memory_region_is_ram(section->mr) &&
301             !memory_region_is_iommu(section->mr)) ||
302            /*
303             * Sizing an enabled 64-bit BAR can cause spurious mappings to
304             * addresses in the upper part of the 64-bit address space.  These
305             * are never accessed by the CPU and beyond the address width of
306             * some IOMMU hardware.  TODO: VFIO should tell us the IOMMU width.
307             */
308            section->offset_within_address_space & (1ULL << 63);
309 }
310 
311 /* Called with rcu_read_lock held.  */
312 static bool vfio_get_vaddr(IOMMUTLBEntry *iotlb, void **vaddr,
313                            bool *read_only)
314 {
315     MemoryRegion *mr;
316     hwaddr xlat;
317     hwaddr len = iotlb->addr_mask + 1;
318     bool writable = iotlb->perm & IOMMU_WO;
319 
320     /*
321      * The IOMMU TLB entry we have just covers translation through
322      * this IOMMU to its immediate target.  We need to translate
323      * it the rest of the way through to memory.
324      */
325     mr = address_space_translate(&address_space_memory,
326                                  iotlb->translated_addr,
327                                  &xlat, &len, writable,
328                                  MEMTXATTRS_UNSPECIFIED);
329     if (!memory_region_is_ram(mr)) {
330         error_report("iommu map to non memory area %"HWADDR_PRIx"",
331                      xlat);
332         return false;
333     }
334 
335     /*
336      * Translation truncates length to the IOMMU page size,
337      * check that it did not truncate too much.
338      */
339     if (len & iotlb->addr_mask) {
340         error_report("iommu has granularity incompatible with target AS");
341         return false;
342     }
343 
344     *vaddr = memory_region_get_ram_ptr(mr) + xlat;
345     *read_only = !writable || mr->readonly;
346 
347     return true;
348 }
349 
350 static void vfio_iommu_map_notify(IOMMUNotifier *n, IOMMUTLBEntry *iotlb)
351 {
352     VFIOGuestIOMMU *giommu = container_of(n, VFIOGuestIOMMU, n);
353     VFIOContainer *container = giommu->container;
354     hwaddr iova = iotlb->iova + giommu->iommu_offset;
355     bool read_only;
356     void *vaddr;
357     int ret;
358 
359     trace_vfio_iommu_map_notify(iotlb->perm == IOMMU_NONE ? "UNMAP" : "MAP",
360                                 iova, iova + iotlb->addr_mask);
361 
362     if (iotlb->target_as != &address_space_memory) {
363         error_report("Wrong target AS \"%s\", only system memory is allowed",
364                      iotlb->target_as->name ? iotlb->target_as->name : "none");
365         return;
366     }
367 
368     rcu_read_lock();
369 
370     if ((iotlb->perm & IOMMU_RW) != IOMMU_NONE) {
371         if (!vfio_get_vaddr(iotlb, &vaddr, &read_only)) {
372             goto out;
373         }
374         /*
375          * vaddr is only valid until rcu_read_unlock(). But after
376          * vfio_dma_map has set up the mapping the pages will be
377          * pinned by the kernel. This makes sure that the RAM backend
378          * of vaddr will always be there, even if the memory object is
379          * destroyed and its backing memory munmap-ed.
380          */
381         ret = vfio_dma_map(container, iova,
382                            iotlb->addr_mask + 1, vaddr,
383                            read_only);
384         if (ret) {
385             error_report("vfio_dma_map(%p, 0x%"HWADDR_PRIx", "
386                          "0x%"HWADDR_PRIx", %p) = %d (%m)",
387                          container, iova,
388                          iotlb->addr_mask + 1, vaddr, ret);
389         }
390     } else {
391         ret = vfio_dma_unmap(container, iova, iotlb->addr_mask + 1);
392         if (ret) {
393             error_report("vfio_dma_unmap(%p, 0x%"HWADDR_PRIx", "
394                          "0x%"HWADDR_PRIx") = %d (%m)",
395                          container, iova,
396                          iotlb->addr_mask + 1, ret);
397         }
398     }
399 out:
400     rcu_read_unlock();
401 }
402 
403 static void vfio_listener_region_add(MemoryListener *listener,
404                                      MemoryRegionSection *section)
405 {
406     VFIOContainer *container = container_of(listener, VFIOContainer, listener);
407     hwaddr iova, end;
408     Int128 llend, llsize;
409     void *vaddr;
410     int ret;
411     VFIOHostDMAWindow *hostwin;
412     bool hostwin_found;
413 
414     if (vfio_listener_skipped_section(section)) {
415         trace_vfio_listener_region_add_skip(
416                 section->offset_within_address_space,
417                 section->offset_within_address_space +
418                 int128_get64(int128_sub(section->size, int128_one())));
419         return;
420     }
421 
422     if (unlikely((section->offset_within_address_space & ~TARGET_PAGE_MASK) !=
423                  (section->offset_within_region & ~TARGET_PAGE_MASK))) {
424         error_report("%s received unaligned region", __func__);
425         return;
426     }
427 
428     iova = TARGET_PAGE_ALIGN(section->offset_within_address_space);
429     llend = int128_make64(section->offset_within_address_space);
430     llend = int128_add(llend, section->size);
431     llend = int128_and(llend, int128_exts64(TARGET_PAGE_MASK));
432 
433     if (int128_ge(int128_make64(iova), llend)) {
434         return;
435     }
436     end = int128_get64(int128_sub(llend, int128_one()));
437 
438     if (container->iommu_type == VFIO_SPAPR_TCE_v2_IOMMU) {
439         hwaddr pgsize = 0;
440 
441         /* For now intersections are not allowed, we may relax this later */
442         QLIST_FOREACH(hostwin, &container->hostwin_list, hostwin_next) {
443             if (ranges_overlap(hostwin->min_iova,
444                                hostwin->max_iova - hostwin->min_iova + 1,
445                                section->offset_within_address_space,
446                                int128_get64(section->size))) {
447                 ret = -1;
448                 goto fail;
449             }
450         }
451 
452         ret = vfio_spapr_create_window(container, section, &pgsize);
453         if (ret) {
454             goto fail;
455         }
456 
457         vfio_host_win_add(container, section->offset_within_address_space,
458                           section->offset_within_address_space +
459                           int128_get64(section->size) - 1, pgsize);
460 #ifdef CONFIG_KVM
461         if (kvm_enabled()) {
462             VFIOGroup *group;
463             IOMMUMemoryRegion *iommu_mr = IOMMU_MEMORY_REGION(section->mr);
464             struct kvm_vfio_spapr_tce param;
465             struct kvm_device_attr attr = {
466                 .group = KVM_DEV_VFIO_GROUP,
467                 .attr = KVM_DEV_VFIO_GROUP_SET_SPAPR_TCE,
468                 .addr = (uint64_t)(unsigned long)&param,
469             };
470 
471             if (!memory_region_iommu_get_attr(iommu_mr, IOMMU_ATTR_SPAPR_TCE_FD,
472                                               &param.tablefd)) {
473                 QLIST_FOREACH(group, &container->group_list, container_next) {
474                     param.groupfd = group->fd;
475                     if (ioctl(vfio_kvm_device_fd, KVM_SET_DEVICE_ATTR, &attr)) {
476                         error_report("vfio: failed to setup fd %d "
477                                      "for a group with fd %d: %s",
478                                      param.tablefd, param.groupfd,
479                                      strerror(errno));
480                         return;
481                     }
482                     trace_vfio_spapr_group_attach(param.groupfd, param.tablefd);
483                 }
484             }
485         }
486 #endif
487     }
488 
489     hostwin_found = false;
490     QLIST_FOREACH(hostwin, &container->hostwin_list, hostwin_next) {
491         if (hostwin->min_iova <= iova && end <= hostwin->max_iova) {
492             hostwin_found = true;
493             break;
494         }
495     }
496 
497     if (!hostwin_found) {
498         error_report("vfio: IOMMU container %p can't map guest IOVA region"
499                      " 0x%"HWADDR_PRIx"..0x%"HWADDR_PRIx,
500                      container, iova, end);
501         ret = -EFAULT;
502         goto fail;
503     }
504 
505     memory_region_ref(section->mr);
506 
507     if (memory_region_is_iommu(section->mr)) {
508         VFIOGuestIOMMU *giommu;
509         IOMMUMemoryRegion *iommu_mr = IOMMU_MEMORY_REGION(section->mr);
510         int iommu_idx;
511 
512         trace_vfio_listener_region_add_iommu(iova, end);
513         /*
514          * FIXME: For VFIO iommu types which have KVM acceleration to
515          * avoid bouncing all map/unmaps through qemu this way, this
516          * would be the right place to wire that up (tell the KVM
517          * device emulation the VFIO iommu handles to use).
518          */
519         giommu = g_malloc0(sizeof(*giommu));
520         giommu->iommu = iommu_mr;
521         giommu->iommu_offset = section->offset_within_address_space -
522                                section->offset_within_region;
523         giommu->container = container;
524         llend = int128_add(int128_make64(section->offset_within_region),
525                            section->size);
526         llend = int128_sub(llend, int128_one());
527         iommu_idx = memory_region_iommu_attrs_to_index(iommu_mr,
528                                                        MEMTXATTRS_UNSPECIFIED);
529         iommu_notifier_init(&giommu->n, vfio_iommu_map_notify,
530                             IOMMU_NOTIFIER_ALL,
531                             section->offset_within_region,
532                             int128_get64(llend),
533                             iommu_idx);
534         QLIST_INSERT_HEAD(&container->giommu_list, giommu, giommu_next);
535 
536         memory_region_register_iommu_notifier(section->mr, &giommu->n);
537         memory_region_iommu_replay(giommu->iommu, &giommu->n);
538 
539         return;
540     }
541 
542     /* Here we assume that memory_region_is_ram(section->mr)==true */
543 
544     vaddr = memory_region_get_ram_ptr(section->mr) +
545             section->offset_within_region +
546             (iova - section->offset_within_address_space);
547 
548     trace_vfio_listener_region_add_ram(iova, end, vaddr);
549 
550     llsize = int128_sub(llend, int128_make64(iova));
551 
552     if (memory_region_is_ram_device(section->mr)) {
553         hwaddr pgmask = (1ULL << ctz64(hostwin->iova_pgsizes)) - 1;
554 
555         if ((iova & pgmask) || (int128_get64(llsize) & pgmask)) {
556             trace_vfio_listener_region_add_no_dma_map(
557                 memory_region_name(section->mr),
558                 section->offset_within_address_space,
559                 int128_getlo(section->size),
560                 pgmask + 1);
561             return;
562         }
563     }
564 
565     ret = vfio_dma_map(container, iova, int128_get64(llsize),
566                        vaddr, section->readonly);
567     if (ret) {
568         error_report("vfio_dma_map(%p, 0x%"HWADDR_PRIx", "
569                      "0x%"HWADDR_PRIx", %p) = %d (%m)",
570                      container, iova, int128_get64(llsize), vaddr, ret);
571         if (memory_region_is_ram_device(section->mr)) {
572             /* Allow unexpected mappings not to be fatal for RAM devices */
573             return;
574         }
575         goto fail;
576     }
577 
578     return;
579 
580 fail:
581     if (memory_region_is_ram_device(section->mr)) {
582         error_report("failed to vfio_dma_map. pci p2p may not work");
583         return;
584     }
585     /*
586      * On the initfn path, store the first error in the container so we
587      * can gracefully fail.  Runtime, there's not much we can do other
588      * than throw a hardware error.
589      */
590     if (!container->initialized) {
591         if (!container->error) {
592             container->error = ret;
593         }
594     } else {
595         hw_error("vfio: DMA mapping failed, unable to continue");
596     }
597 }
598 
599 static void vfio_listener_region_del(MemoryListener *listener,
600                                      MemoryRegionSection *section)
601 {
602     VFIOContainer *container = container_of(listener, VFIOContainer, listener);
603     hwaddr iova, end;
604     Int128 llend, llsize;
605     int ret;
606     bool try_unmap = true;
607 
608     if (vfio_listener_skipped_section(section)) {
609         trace_vfio_listener_region_del_skip(
610                 section->offset_within_address_space,
611                 section->offset_within_address_space +
612                 int128_get64(int128_sub(section->size, int128_one())));
613         return;
614     }
615 
616     if (unlikely((section->offset_within_address_space & ~TARGET_PAGE_MASK) !=
617                  (section->offset_within_region & ~TARGET_PAGE_MASK))) {
618         error_report("%s received unaligned region", __func__);
619         return;
620     }
621 
622     if (memory_region_is_iommu(section->mr)) {
623         VFIOGuestIOMMU *giommu;
624 
625         QLIST_FOREACH(giommu, &container->giommu_list, giommu_next) {
626             if (MEMORY_REGION(giommu->iommu) == section->mr &&
627                 giommu->n.start == section->offset_within_region) {
628                 memory_region_unregister_iommu_notifier(section->mr,
629                                                         &giommu->n);
630                 QLIST_REMOVE(giommu, giommu_next);
631                 g_free(giommu);
632                 break;
633             }
634         }
635 
636         /*
637          * FIXME: We assume the one big unmap below is adequate to
638          * remove any individual page mappings in the IOMMU which
639          * might have been copied into VFIO. This works for a page table
640          * based IOMMU where a big unmap flattens a large range of IO-PTEs.
641          * That may not be true for all IOMMU types.
642          */
643     }
644 
645     iova = TARGET_PAGE_ALIGN(section->offset_within_address_space);
646     llend = int128_make64(section->offset_within_address_space);
647     llend = int128_add(llend, section->size);
648     llend = int128_and(llend, int128_exts64(TARGET_PAGE_MASK));
649 
650     if (int128_ge(int128_make64(iova), llend)) {
651         return;
652     }
653     end = int128_get64(int128_sub(llend, int128_one()));
654 
655     llsize = int128_sub(llend, int128_make64(iova));
656 
657     trace_vfio_listener_region_del(iova, end);
658 
659     if (memory_region_is_ram_device(section->mr)) {
660         hwaddr pgmask;
661         VFIOHostDMAWindow *hostwin;
662         bool hostwin_found = false;
663 
664         QLIST_FOREACH(hostwin, &container->hostwin_list, hostwin_next) {
665             if (hostwin->min_iova <= iova && end <= hostwin->max_iova) {
666                 hostwin_found = true;
667                 break;
668             }
669         }
670         assert(hostwin_found); /* or region_add() would have failed */
671 
672         pgmask = (1ULL << ctz64(hostwin->iova_pgsizes)) - 1;
673         try_unmap = !((iova & pgmask) || (int128_get64(llsize) & pgmask));
674     }
675 
676     if (try_unmap) {
677         ret = vfio_dma_unmap(container, iova, int128_get64(llsize));
678         if (ret) {
679             error_report("vfio_dma_unmap(%p, 0x%"HWADDR_PRIx", "
680                          "0x%"HWADDR_PRIx") = %d (%m)",
681                          container, iova, int128_get64(llsize), ret);
682         }
683     }
684 
685     memory_region_unref(section->mr);
686 
687     if (container->iommu_type == VFIO_SPAPR_TCE_v2_IOMMU) {
688         vfio_spapr_remove_window(container,
689                                  section->offset_within_address_space);
690         if (vfio_host_win_del(container,
691                               section->offset_within_address_space,
692                               section->offset_within_address_space +
693                               int128_get64(section->size) - 1) < 0) {
694             hw_error("%s: Cannot delete missing window at %"HWADDR_PRIx,
695                      __func__, section->offset_within_address_space);
696         }
697     }
698 }
699 
700 static const MemoryListener vfio_memory_listener = {
701     .region_add = vfio_listener_region_add,
702     .region_del = vfio_listener_region_del,
703 };
704 
705 static void vfio_listener_release(VFIOContainer *container)
706 {
707     memory_listener_unregister(&container->listener);
708     if (container->iommu_type == VFIO_SPAPR_TCE_v2_IOMMU) {
709         memory_listener_unregister(&container->prereg_listener);
710     }
711 }
712 
713 static struct vfio_info_cap_header *
714 vfio_get_region_info_cap(struct vfio_region_info *info, uint16_t id)
715 {
716     struct vfio_info_cap_header *hdr;
717     void *ptr = info;
718 
719     if (!(info->flags & VFIO_REGION_INFO_FLAG_CAPS)) {
720         return NULL;
721     }
722 
723     for (hdr = ptr + info->cap_offset; hdr != ptr; hdr = ptr + hdr->next) {
724         if (hdr->id == id) {
725             return hdr;
726         }
727     }
728 
729     return NULL;
730 }
731 
732 static int vfio_setup_region_sparse_mmaps(VFIORegion *region,
733                                           struct vfio_region_info *info)
734 {
735     struct vfio_info_cap_header *hdr;
736     struct vfio_region_info_cap_sparse_mmap *sparse;
737     int i, j;
738 
739     hdr = vfio_get_region_info_cap(info, VFIO_REGION_INFO_CAP_SPARSE_MMAP);
740     if (!hdr) {
741         return -ENODEV;
742     }
743 
744     sparse = container_of(hdr, struct vfio_region_info_cap_sparse_mmap, header);
745 
746     trace_vfio_region_sparse_mmap_header(region->vbasedev->name,
747                                          region->nr, sparse->nr_areas);
748 
749     region->mmaps = g_new0(VFIOMmap, sparse->nr_areas);
750 
751     for (i = 0, j = 0; i < sparse->nr_areas; i++) {
752         trace_vfio_region_sparse_mmap_entry(i, sparse->areas[i].offset,
753                                             sparse->areas[i].offset +
754                                             sparse->areas[i].size);
755 
756         if (sparse->areas[i].size) {
757             region->mmaps[j].offset = sparse->areas[i].offset;
758             region->mmaps[j].size = sparse->areas[i].size;
759             j++;
760         }
761     }
762 
763     region->nr_mmaps = j;
764     region->mmaps = g_realloc(region->mmaps, j * sizeof(VFIOMmap));
765 
766     return 0;
767 }
768 
769 int vfio_region_setup(Object *obj, VFIODevice *vbasedev, VFIORegion *region,
770                       int index, const char *name)
771 {
772     struct vfio_region_info *info;
773     int ret;
774 
775     ret = vfio_get_region_info(vbasedev, index, &info);
776     if (ret) {
777         return ret;
778     }
779 
780     region->vbasedev = vbasedev;
781     region->flags = info->flags;
782     region->size = info->size;
783     region->fd_offset = info->offset;
784     region->nr = index;
785 
786     if (region->size) {
787         region->mem = g_new0(MemoryRegion, 1);
788         memory_region_init_io(region->mem, obj, &vfio_region_ops,
789                               region, name, region->size);
790 
791         if (!vbasedev->no_mmap &&
792             region->flags & VFIO_REGION_INFO_FLAG_MMAP) {
793 
794             ret = vfio_setup_region_sparse_mmaps(region, info);
795 
796             if (ret) {
797                 region->nr_mmaps = 1;
798                 region->mmaps = g_new0(VFIOMmap, region->nr_mmaps);
799                 region->mmaps[0].offset = 0;
800                 region->mmaps[0].size = region->size;
801             }
802         }
803     }
804 
805     g_free(info);
806 
807     trace_vfio_region_setup(vbasedev->name, index, name,
808                             region->flags, region->fd_offset, region->size);
809     return 0;
810 }
811 
812 int vfio_region_mmap(VFIORegion *region)
813 {
814     int i, prot = 0;
815     char *name;
816 
817     if (!region->mem) {
818         return 0;
819     }
820 
821     prot |= region->flags & VFIO_REGION_INFO_FLAG_READ ? PROT_READ : 0;
822     prot |= region->flags & VFIO_REGION_INFO_FLAG_WRITE ? PROT_WRITE : 0;
823 
824     for (i = 0; i < region->nr_mmaps; i++) {
825         region->mmaps[i].mmap = mmap(NULL, region->mmaps[i].size, prot,
826                                      MAP_SHARED, region->vbasedev->fd,
827                                      region->fd_offset +
828                                      region->mmaps[i].offset);
829         if (region->mmaps[i].mmap == MAP_FAILED) {
830             int ret = -errno;
831 
832             trace_vfio_region_mmap_fault(memory_region_name(region->mem), i,
833                                          region->fd_offset +
834                                          region->mmaps[i].offset,
835                                          region->fd_offset +
836                                          region->mmaps[i].offset +
837                                          region->mmaps[i].size - 1, ret);
838 
839             region->mmaps[i].mmap = NULL;
840 
841             for (i--; i >= 0; i--) {
842                 memory_region_del_subregion(region->mem, &region->mmaps[i].mem);
843                 munmap(region->mmaps[i].mmap, region->mmaps[i].size);
844                 object_unparent(OBJECT(&region->mmaps[i].mem));
845                 region->mmaps[i].mmap = NULL;
846             }
847 
848             return ret;
849         }
850 
851         name = g_strdup_printf("%s mmaps[%d]",
852                                memory_region_name(region->mem), i);
853         memory_region_init_ram_device_ptr(&region->mmaps[i].mem,
854                                           memory_region_owner(region->mem),
855                                           name, region->mmaps[i].size,
856                                           region->mmaps[i].mmap);
857         g_free(name);
858         memory_region_add_subregion(region->mem, region->mmaps[i].offset,
859                                     &region->mmaps[i].mem);
860 
861         trace_vfio_region_mmap(memory_region_name(&region->mmaps[i].mem),
862                                region->mmaps[i].offset,
863                                region->mmaps[i].offset +
864                                region->mmaps[i].size - 1);
865     }
866 
867     return 0;
868 }
869 
870 void vfio_region_exit(VFIORegion *region)
871 {
872     int i;
873 
874     if (!region->mem) {
875         return;
876     }
877 
878     for (i = 0; i < region->nr_mmaps; i++) {
879         if (region->mmaps[i].mmap) {
880             memory_region_del_subregion(region->mem, &region->mmaps[i].mem);
881         }
882     }
883 
884     trace_vfio_region_exit(region->vbasedev->name, region->nr);
885 }
886 
887 void vfio_region_finalize(VFIORegion *region)
888 {
889     int i;
890 
891     if (!region->mem) {
892         return;
893     }
894 
895     for (i = 0; i < region->nr_mmaps; i++) {
896         if (region->mmaps[i].mmap) {
897             munmap(region->mmaps[i].mmap, region->mmaps[i].size);
898             object_unparent(OBJECT(&region->mmaps[i].mem));
899         }
900     }
901 
902     object_unparent(OBJECT(region->mem));
903 
904     g_free(region->mem);
905     g_free(region->mmaps);
906 
907     trace_vfio_region_finalize(region->vbasedev->name, region->nr);
908 
909     region->mem = NULL;
910     region->mmaps = NULL;
911     region->nr_mmaps = 0;
912     region->size = 0;
913     region->flags = 0;
914     region->nr = 0;
915 }
916 
917 void vfio_region_mmaps_set_enabled(VFIORegion *region, bool enabled)
918 {
919     int i;
920 
921     if (!region->mem) {
922         return;
923     }
924 
925     for (i = 0; i < region->nr_mmaps; i++) {
926         if (region->mmaps[i].mmap) {
927             memory_region_set_enabled(&region->mmaps[i].mem, enabled);
928         }
929     }
930 
931     trace_vfio_region_mmaps_set_enabled(memory_region_name(region->mem),
932                                         enabled);
933 }
934 
935 void vfio_reset_handler(void *opaque)
936 {
937     VFIOGroup *group;
938     VFIODevice *vbasedev;
939 
940     QLIST_FOREACH(group, &vfio_group_list, next) {
941         QLIST_FOREACH(vbasedev, &group->device_list, next) {
942             if (vbasedev->dev->realized) {
943                 vbasedev->ops->vfio_compute_needs_reset(vbasedev);
944             }
945         }
946     }
947 
948     QLIST_FOREACH(group, &vfio_group_list, next) {
949         QLIST_FOREACH(vbasedev, &group->device_list, next) {
950             if (vbasedev->dev->realized && vbasedev->needs_reset) {
951                 vbasedev->ops->vfio_hot_reset_multi(vbasedev);
952             }
953         }
954     }
955 }
956 
957 static void vfio_kvm_device_add_group(VFIOGroup *group)
958 {
959 #ifdef CONFIG_KVM
960     struct kvm_device_attr attr = {
961         .group = KVM_DEV_VFIO_GROUP,
962         .attr = KVM_DEV_VFIO_GROUP_ADD,
963         .addr = (uint64_t)(unsigned long)&group->fd,
964     };
965 
966     if (!kvm_enabled()) {
967         return;
968     }
969 
970     if (vfio_kvm_device_fd < 0) {
971         struct kvm_create_device cd = {
972             .type = KVM_DEV_TYPE_VFIO,
973         };
974 
975         if (kvm_vm_ioctl(kvm_state, KVM_CREATE_DEVICE, &cd)) {
976             error_report("Failed to create KVM VFIO device: %m");
977             return;
978         }
979 
980         vfio_kvm_device_fd = cd.fd;
981     }
982 
983     if (ioctl(vfio_kvm_device_fd, KVM_SET_DEVICE_ATTR, &attr)) {
984         error_report("Failed to add group %d to KVM VFIO device: %m",
985                      group->groupid);
986     }
987 #endif
988 }
989 
990 static void vfio_kvm_device_del_group(VFIOGroup *group)
991 {
992 #ifdef CONFIG_KVM
993     struct kvm_device_attr attr = {
994         .group = KVM_DEV_VFIO_GROUP,
995         .attr = KVM_DEV_VFIO_GROUP_DEL,
996         .addr = (uint64_t)(unsigned long)&group->fd,
997     };
998 
999     if (vfio_kvm_device_fd < 0) {
1000         return;
1001     }
1002 
1003     if (ioctl(vfio_kvm_device_fd, KVM_SET_DEVICE_ATTR, &attr)) {
1004         error_report("Failed to remove group %d from KVM VFIO device: %m",
1005                      group->groupid);
1006     }
1007 #endif
1008 }
1009 
1010 static VFIOAddressSpace *vfio_get_address_space(AddressSpace *as)
1011 {
1012     VFIOAddressSpace *space;
1013 
1014     QLIST_FOREACH(space, &vfio_address_spaces, list) {
1015         if (space->as == as) {
1016             return space;
1017         }
1018     }
1019 
1020     /* No suitable VFIOAddressSpace, create a new one */
1021     space = g_malloc0(sizeof(*space));
1022     space->as = as;
1023     QLIST_INIT(&space->containers);
1024 
1025     QLIST_INSERT_HEAD(&vfio_address_spaces, space, list);
1026 
1027     return space;
1028 }
1029 
1030 static void vfio_put_address_space(VFIOAddressSpace *space)
1031 {
1032     if (QLIST_EMPTY(&space->containers)) {
1033         QLIST_REMOVE(space, list);
1034         g_free(space);
1035     }
1036 }
1037 
1038 static int vfio_connect_container(VFIOGroup *group, AddressSpace *as,
1039                                   Error **errp)
1040 {
1041     VFIOContainer *container;
1042     int ret, fd;
1043     VFIOAddressSpace *space;
1044 
1045     space = vfio_get_address_space(as);
1046 
1047     QLIST_FOREACH(container, &space->containers, next) {
1048         if (!ioctl(group->fd, VFIO_GROUP_SET_CONTAINER, &container->fd)) {
1049             group->container = container;
1050             QLIST_INSERT_HEAD(&container->group_list, group, container_next);
1051             vfio_kvm_device_add_group(group);
1052             return 0;
1053         }
1054     }
1055 
1056     fd = qemu_open("/dev/vfio/vfio", O_RDWR);
1057     if (fd < 0) {
1058         error_setg_errno(errp, errno, "failed to open /dev/vfio/vfio");
1059         ret = -errno;
1060         goto put_space_exit;
1061     }
1062 
1063     ret = ioctl(fd, VFIO_GET_API_VERSION);
1064     if (ret != VFIO_API_VERSION) {
1065         error_setg(errp, "supported vfio version: %d, "
1066                    "reported version: %d", VFIO_API_VERSION, ret);
1067         ret = -EINVAL;
1068         goto close_fd_exit;
1069     }
1070 
1071     container = g_malloc0(sizeof(*container));
1072     container->space = space;
1073     container->fd = fd;
1074     QLIST_INIT(&container->giommu_list);
1075     QLIST_INIT(&container->hostwin_list);
1076     if (ioctl(fd, VFIO_CHECK_EXTENSION, VFIO_TYPE1_IOMMU) ||
1077         ioctl(fd, VFIO_CHECK_EXTENSION, VFIO_TYPE1v2_IOMMU)) {
1078         bool v2 = !!ioctl(fd, VFIO_CHECK_EXTENSION, VFIO_TYPE1v2_IOMMU);
1079         struct vfio_iommu_type1_info info;
1080 
1081         ret = ioctl(group->fd, VFIO_GROUP_SET_CONTAINER, &fd);
1082         if (ret) {
1083             error_setg_errno(errp, errno, "failed to set group container");
1084             ret = -errno;
1085             goto free_container_exit;
1086         }
1087 
1088         container->iommu_type = v2 ? VFIO_TYPE1v2_IOMMU : VFIO_TYPE1_IOMMU;
1089         ret = ioctl(fd, VFIO_SET_IOMMU, container->iommu_type);
1090         if (ret) {
1091             error_setg_errno(errp, errno, "failed to set iommu for container");
1092             ret = -errno;
1093             goto free_container_exit;
1094         }
1095 
1096         /*
1097          * FIXME: This assumes that a Type1 IOMMU can map any 64-bit
1098          * IOVA whatsoever.  That's not actually true, but the current
1099          * kernel interface doesn't tell us what it can map, and the
1100          * existing Type1 IOMMUs generally support any IOVA we're
1101          * going to actually try in practice.
1102          */
1103         info.argsz = sizeof(info);
1104         ret = ioctl(fd, VFIO_IOMMU_GET_INFO, &info);
1105         /* Ignore errors */
1106         if (ret || !(info.flags & VFIO_IOMMU_INFO_PGSIZES)) {
1107             /* Assume 4k IOVA page size */
1108             info.iova_pgsizes = 4096;
1109         }
1110         vfio_host_win_add(container, 0, (hwaddr)-1, info.iova_pgsizes);
1111     } else if (ioctl(fd, VFIO_CHECK_EXTENSION, VFIO_SPAPR_TCE_IOMMU) ||
1112                ioctl(fd, VFIO_CHECK_EXTENSION, VFIO_SPAPR_TCE_v2_IOMMU)) {
1113         struct vfio_iommu_spapr_tce_info info;
1114         bool v2 = !!ioctl(fd, VFIO_CHECK_EXTENSION, VFIO_SPAPR_TCE_v2_IOMMU);
1115 
1116         ret = ioctl(group->fd, VFIO_GROUP_SET_CONTAINER, &fd);
1117         if (ret) {
1118             error_setg_errno(errp, errno, "failed to set group container");
1119             ret = -errno;
1120             goto free_container_exit;
1121         }
1122         container->iommu_type =
1123             v2 ? VFIO_SPAPR_TCE_v2_IOMMU : VFIO_SPAPR_TCE_IOMMU;
1124         ret = ioctl(fd, VFIO_SET_IOMMU, container->iommu_type);
1125         if (ret) {
1126             container->iommu_type = VFIO_SPAPR_TCE_IOMMU;
1127             v2 = false;
1128             ret = ioctl(fd, VFIO_SET_IOMMU, container->iommu_type);
1129         }
1130         if (ret) {
1131             error_setg_errno(errp, errno, "failed to set iommu for container");
1132             ret = -errno;
1133             goto free_container_exit;
1134         }
1135 
1136         /*
1137          * The host kernel code implementing VFIO_IOMMU_DISABLE is called
1138          * when container fd is closed so we do not call it explicitly
1139          * in this file.
1140          */
1141         if (!v2) {
1142             ret = ioctl(fd, VFIO_IOMMU_ENABLE);
1143             if (ret) {
1144                 error_setg_errno(errp, errno, "failed to enable container");
1145                 ret = -errno;
1146                 goto free_container_exit;
1147             }
1148         } else {
1149             container->prereg_listener = vfio_prereg_listener;
1150 
1151             memory_listener_register(&container->prereg_listener,
1152                                      &address_space_memory);
1153             if (container->error) {
1154                 memory_listener_unregister(&container->prereg_listener);
1155                 ret = container->error;
1156                 error_setg(errp,
1157                     "RAM memory listener initialization failed for container");
1158                 goto free_container_exit;
1159             }
1160         }
1161 
1162         info.argsz = sizeof(info);
1163         ret = ioctl(fd, VFIO_IOMMU_SPAPR_TCE_GET_INFO, &info);
1164         if (ret) {
1165             error_setg_errno(errp, errno,
1166                              "VFIO_IOMMU_SPAPR_TCE_GET_INFO failed");
1167             ret = -errno;
1168             if (v2) {
1169                 memory_listener_unregister(&container->prereg_listener);
1170             }
1171             goto free_container_exit;
1172         }
1173 
1174         if (v2) {
1175             /*
1176              * There is a default window in just created container.
1177              * To make region_add/del simpler, we better remove this
1178              * window now and let those iommu_listener callbacks
1179              * create/remove them when needed.
1180              */
1181             ret = vfio_spapr_remove_window(container, info.dma32_window_start);
1182             if (ret) {
1183                 error_setg_errno(errp, -ret,
1184                                  "failed to remove existing window");
1185                 goto free_container_exit;
1186             }
1187         } else {
1188             /* The default table uses 4K pages */
1189             vfio_host_win_add(container, info.dma32_window_start,
1190                               info.dma32_window_start +
1191                               info.dma32_window_size - 1,
1192                               0x1000);
1193         }
1194     } else {
1195         error_setg(errp, "No available IOMMU models");
1196         ret = -EINVAL;
1197         goto free_container_exit;
1198     }
1199 
1200     vfio_kvm_device_add_group(group);
1201 
1202     QLIST_INIT(&container->group_list);
1203     QLIST_INSERT_HEAD(&space->containers, container, next);
1204 
1205     group->container = container;
1206     QLIST_INSERT_HEAD(&container->group_list, group, container_next);
1207 
1208     container->listener = vfio_memory_listener;
1209 
1210     memory_listener_register(&container->listener, container->space->as);
1211 
1212     if (container->error) {
1213         ret = container->error;
1214         error_setg_errno(errp, -ret,
1215                          "memory listener initialization failed for container");
1216         goto listener_release_exit;
1217     }
1218 
1219     container->initialized = true;
1220 
1221     return 0;
1222 listener_release_exit:
1223     QLIST_REMOVE(group, container_next);
1224     QLIST_REMOVE(container, next);
1225     vfio_kvm_device_del_group(group);
1226     vfio_listener_release(container);
1227 
1228 free_container_exit:
1229     g_free(container);
1230 
1231 close_fd_exit:
1232     close(fd);
1233 
1234 put_space_exit:
1235     vfio_put_address_space(space);
1236 
1237     return ret;
1238 }
1239 
1240 static void vfio_disconnect_container(VFIOGroup *group)
1241 {
1242     VFIOContainer *container = group->container;
1243 
1244     QLIST_REMOVE(group, container_next);
1245     group->container = NULL;
1246 
1247     /*
1248      * Explicitly release the listener first before unset container,
1249      * since unset may destroy the backend container if it's the last
1250      * group.
1251      */
1252     if (QLIST_EMPTY(&container->group_list)) {
1253         vfio_listener_release(container);
1254     }
1255 
1256     if (ioctl(group->fd, VFIO_GROUP_UNSET_CONTAINER, &container->fd)) {
1257         error_report("vfio: error disconnecting group %d from container",
1258                      group->groupid);
1259     }
1260 
1261     if (QLIST_EMPTY(&container->group_list)) {
1262         VFIOAddressSpace *space = container->space;
1263         VFIOGuestIOMMU *giommu, *tmp;
1264 
1265         QLIST_REMOVE(container, next);
1266 
1267         QLIST_FOREACH_SAFE(giommu, &container->giommu_list, giommu_next, tmp) {
1268             memory_region_unregister_iommu_notifier(
1269                     MEMORY_REGION(giommu->iommu), &giommu->n);
1270             QLIST_REMOVE(giommu, giommu_next);
1271             g_free(giommu);
1272         }
1273 
1274         trace_vfio_disconnect_container(container->fd);
1275         close(container->fd);
1276         g_free(container);
1277 
1278         vfio_put_address_space(space);
1279     }
1280 }
1281 
1282 VFIOGroup *vfio_get_group(int groupid, AddressSpace *as, Error **errp)
1283 {
1284     VFIOGroup *group;
1285     char path[32];
1286     struct vfio_group_status status = { .argsz = sizeof(status) };
1287 
1288     QLIST_FOREACH(group, &vfio_group_list, next) {
1289         if (group->groupid == groupid) {
1290             /* Found it.  Now is it already in the right context? */
1291             if (group->container->space->as == as) {
1292                 return group;
1293             } else {
1294                 error_setg(errp, "group %d used in multiple address spaces",
1295                            group->groupid);
1296                 return NULL;
1297             }
1298         }
1299     }
1300 
1301     group = g_malloc0(sizeof(*group));
1302 
1303     snprintf(path, sizeof(path), "/dev/vfio/%d", groupid);
1304     group->fd = qemu_open(path, O_RDWR);
1305     if (group->fd < 0) {
1306         error_setg_errno(errp, errno, "failed to open %s", path);
1307         goto free_group_exit;
1308     }
1309 
1310     if (ioctl(group->fd, VFIO_GROUP_GET_STATUS, &status)) {
1311         error_setg_errno(errp, errno, "failed to get group %d status", groupid);
1312         goto close_fd_exit;
1313     }
1314 
1315     if (!(status.flags & VFIO_GROUP_FLAGS_VIABLE)) {
1316         error_setg(errp, "group %d is not viable", groupid);
1317         error_append_hint(errp,
1318                           "Please ensure all devices within the iommu_group "
1319                           "are bound to their vfio bus driver.\n");
1320         goto close_fd_exit;
1321     }
1322 
1323     group->groupid = groupid;
1324     QLIST_INIT(&group->device_list);
1325 
1326     if (vfio_connect_container(group, as, errp)) {
1327         error_prepend(errp, "failed to setup container for group %d: ",
1328                       groupid);
1329         goto close_fd_exit;
1330     }
1331 
1332     if (QLIST_EMPTY(&vfio_group_list)) {
1333         qemu_register_reset(vfio_reset_handler, NULL);
1334     }
1335 
1336     QLIST_INSERT_HEAD(&vfio_group_list, group, next);
1337 
1338     return group;
1339 
1340 close_fd_exit:
1341     close(group->fd);
1342 
1343 free_group_exit:
1344     g_free(group);
1345 
1346     return NULL;
1347 }
1348 
1349 void vfio_put_group(VFIOGroup *group)
1350 {
1351     if (!group || !QLIST_EMPTY(&group->device_list)) {
1352         return;
1353     }
1354 
1355     vfio_kvm_device_del_group(group);
1356     vfio_disconnect_container(group);
1357     QLIST_REMOVE(group, next);
1358     trace_vfio_put_group(group->fd);
1359     close(group->fd);
1360     g_free(group);
1361 
1362     if (QLIST_EMPTY(&vfio_group_list)) {
1363         qemu_unregister_reset(vfio_reset_handler, NULL);
1364     }
1365 }
1366 
1367 int vfio_get_device(VFIOGroup *group, const char *name,
1368                     VFIODevice *vbasedev, Error **errp)
1369 {
1370     struct vfio_device_info dev_info = { .argsz = sizeof(dev_info) };
1371     int ret, fd;
1372 
1373     fd = ioctl(group->fd, VFIO_GROUP_GET_DEVICE_FD, name);
1374     if (fd < 0) {
1375         error_setg_errno(errp, errno, "error getting device from group %d",
1376                          group->groupid);
1377         error_append_hint(errp,
1378                       "Verify all devices in group %d are bound to vfio-<bus> "
1379                       "or pci-stub and not already in use\n", group->groupid);
1380         return fd;
1381     }
1382 
1383     ret = ioctl(fd, VFIO_DEVICE_GET_INFO, &dev_info);
1384     if (ret) {
1385         error_setg_errno(errp, errno, "error getting device info");
1386         close(fd);
1387         return ret;
1388     }
1389 
1390     vbasedev->fd = fd;
1391     vbasedev->group = group;
1392     QLIST_INSERT_HEAD(&group->device_list, vbasedev, next);
1393 
1394     vbasedev->num_irqs = dev_info.num_irqs;
1395     vbasedev->num_regions = dev_info.num_regions;
1396     vbasedev->flags = dev_info.flags;
1397 
1398     trace_vfio_get_device(name, dev_info.flags, dev_info.num_regions,
1399                           dev_info.num_irqs);
1400 
1401     vbasedev->reset_works = !!(dev_info.flags & VFIO_DEVICE_FLAGS_RESET);
1402     return 0;
1403 }
1404 
1405 void vfio_put_base_device(VFIODevice *vbasedev)
1406 {
1407     if (!vbasedev->group) {
1408         return;
1409     }
1410     QLIST_REMOVE(vbasedev, next);
1411     vbasedev->group = NULL;
1412     trace_vfio_put_base_device(vbasedev->fd);
1413     close(vbasedev->fd);
1414 }
1415 
1416 int vfio_get_region_info(VFIODevice *vbasedev, int index,
1417                          struct vfio_region_info **info)
1418 {
1419     size_t argsz = sizeof(struct vfio_region_info);
1420 
1421     *info = g_malloc0(argsz);
1422 
1423     (*info)->index = index;
1424 retry:
1425     (*info)->argsz = argsz;
1426 
1427     if (ioctl(vbasedev->fd, VFIO_DEVICE_GET_REGION_INFO, *info)) {
1428         g_free(*info);
1429         *info = NULL;
1430         return -errno;
1431     }
1432 
1433     if ((*info)->argsz > argsz) {
1434         argsz = (*info)->argsz;
1435         *info = g_realloc(*info, argsz);
1436 
1437         goto retry;
1438     }
1439 
1440     return 0;
1441 }
1442 
1443 int vfio_get_dev_region_info(VFIODevice *vbasedev, uint32_t type,
1444                              uint32_t subtype, struct vfio_region_info **info)
1445 {
1446     int i;
1447 
1448     for (i = 0; i < vbasedev->num_regions; i++) {
1449         struct vfio_info_cap_header *hdr;
1450         struct vfio_region_info_cap_type *cap_type;
1451 
1452         if (vfio_get_region_info(vbasedev, i, info)) {
1453             continue;
1454         }
1455 
1456         hdr = vfio_get_region_info_cap(*info, VFIO_REGION_INFO_CAP_TYPE);
1457         if (!hdr) {
1458             g_free(*info);
1459             continue;
1460         }
1461 
1462         cap_type = container_of(hdr, struct vfio_region_info_cap_type, header);
1463 
1464         trace_vfio_get_dev_region(vbasedev->name, i,
1465                                   cap_type->type, cap_type->subtype);
1466 
1467         if (cap_type->type == type && cap_type->subtype == subtype) {
1468             return 0;
1469         }
1470 
1471         g_free(*info);
1472     }
1473 
1474     *info = NULL;
1475     return -ENODEV;
1476 }
1477 
1478 bool vfio_has_region_cap(VFIODevice *vbasedev, int region, uint16_t cap_type)
1479 {
1480     struct vfio_region_info *info = NULL;
1481     bool ret = false;
1482 
1483     if (!vfio_get_region_info(vbasedev, region, &info)) {
1484         if (vfio_get_region_info_cap(info, cap_type)) {
1485             ret = true;
1486         }
1487         g_free(info);
1488     }
1489 
1490     return ret;
1491 }
1492 
1493 /*
1494  * Interfaces for IBM EEH (Enhanced Error Handling)
1495  */
1496 static bool vfio_eeh_container_ok(VFIOContainer *container)
1497 {
1498     /*
1499      * As of 2016-03-04 (linux-4.5) the host kernel EEH/VFIO
1500      * implementation is broken if there are multiple groups in a
1501      * container.  The hardware works in units of Partitionable
1502      * Endpoints (== IOMMU groups) and the EEH operations naively
1503      * iterate across all groups in the container, without any logic
1504      * to make sure the groups have their state synchronized.  For
1505      * certain operations (ENABLE) that might be ok, until an error
1506      * occurs, but for others (GET_STATE) it's clearly broken.
1507      */
1508 
1509     /*
1510      * XXX Once fixed kernels exist, test for them here
1511      */
1512 
1513     if (QLIST_EMPTY(&container->group_list)) {
1514         return false;
1515     }
1516 
1517     if (QLIST_NEXT(QLIST_FIRST(&container->group_list), container_next)) {
1518         return false;
1519     }
1520 
1521     return true;
1522 }
1523 
1524 static int vfio_eeh_container_op(VFIOContainer *container, uint32_t op)
1525 {
1526     struct vfio_eeh_pe_op pe_op = {
1527         .argsz = sizeof(pe_op),
1528         .op = op,
1529     };
1530     int ret;
1531 
1532     if (!vfio_eeh_container_ok(container)) {
1533         error_report("vfio/eeh: EEH_PE_OP 0x%x: "
1534                      "kernel requires a container with exactly one group", op);
1535         return -EPERM;
1536     }
1537 
1538     ret = ioctl(container->fd, VFIO_EEH_PE_OP, &pe_op);
1539     if (ret < 0) {
1540         error_report("vfio/eeh: EEH_PE_OP 0x%x failed: %m", op);
1541         return -errno;
1542     }
1543 
1544     return ret;
1545 }
1546 
1547 static VFIOContainer *vfio_eeh_as_container(AddressSpace *as)
1548 {
1549     VFIOAddressSpace *space = vfio_get_address_space(as);
1550     VFIOContainer *container = NULL;
1551 
1552     if (QLIST_EMPTY(&space->containers)) {
1553         /* No containers to act on */
1554         goto out;
1555     }
1556 
1557     container = QLIST_FIRST(&space->containers);
1558 
1559     if (QLIST_NEXT(container, next)) {
1560         /* We don't yet have logic to synchronize EEH state across
1561          * multiple containers */
1562         container = NULL;
1563         goto out;
1564     }
1565 
1566 out:
1567     vfio_put_address_space(space);
1568     return container;
1569 }
1570 
1571 bool vfio_eeh_as_ok(AddressSpace *as)
1572 {
1573     VFIOContainer *container = vfio_eeh_as_container(as);
1574 
1575     return (container != NULL) && vfio_eeh_container_ok(container);
1576 }
1577 
1578 int vfio_eeh_as_op(AddressSpace *as, uint32_t op)
1579 {
1580     VFIOContainer *container = vfio_eeh_as_container(as);
1581 
1582     if (!container) {
1583         return -ENODEV;
1584     }
1585     return vfio_eeh_container_op(container, op);
1586 }
1587