xref: /openbmc/qemu/hw/vfio/common.c (revision 0dacec87)
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     if (!memory_region_is_ram(mr)) {
329         error_report("iommu map to non memory area %"HWADDR_PRIx"",
330                      xlat);
331         return false;
332     }
333 
334     /*
335      * Translation truncates length to the IOMMU page size,
336      * check that it did not truncate too much.
337      */
338     if (len & iotlb->addr_mask) {
339         error_report("iommu has granularity incompatible with target AS");
340         return false;
341     }
342 
343     *vaddr = memory_region_get_ram_ptr(mr) + xlat;
344     *read_only = !writable || mr->readonly;
345 
346     return true;
347 }
348 
349 static void vfio_iommu_map_notify(IOMMUNotifier *n, IOMMUTLBEntry *iotlb)
350 {
351     VFIOGuestIOMMU *giommu = container_of(n, VFIOGuestIOMMU, n);
352     VFIOContainer *container = giommu->container;
353     hwaddr iova = iotlb->iova + giommu->iommu_offset;
354     bool read_only;
355     void *vaddr;
356     int ret;
357 
358     trace_vfio_iommu_map_notify(iotlb->perm == IOMMU_NONE ? "UNMAP" : "MAP",
359                                 iova, iova + iotlb->addr_mask);
360 
361     if (iotlb->target_as != &address_space_memory) {
362         error_report("Wrong target AS \"%s\", only system memory is allowed",
363                      iotlb->target_as->name ? iotlb->target_as->name : "none");
364         return;
365     }
366 
367     rcu_read_lock();
368 
369     if ((iotlb->perm & IOMMU_RW) != IOMMU_NONE) {
370         if (!vfio_get_vaddr(iotlb, &vaddr, &read_only)) {
371             goto out;
372         }
373         /*
374          * vaddr is only valid until rcu_read_unlock(). But after
375          * vfio_dma_map has set up the mapping the pages will be
376          * pinned by the kernel. This makes sure that the RAM backend
377          * of vaddr will always be there, even if the memory object is
378          * destroyed and its backing memory munmap-ed.
379          */
380         ret = vfio_dma_map(container, iova,
381                            iotlb->addr_mask + 1, vaddr,
382                            read_only);
383         if (ret) {
384             error_report("vfio_dma_map(%p, 0x%"HWADDR_PRIx", "
385                          "0x%"HWADDR_PRIx", %p) = %d (%m)",
386                          container, iova,
387                          iotlb->addr_mask + 1, vaddr, ret);
388         }
389     } else {
390         ret = vfio_dma_unmap(container, iova, iotlb->addr_mask + 1);
391         if (ret) {
392             error_report("vfio_dma_unmap(%p, 0x%"HWADDR_PRIx", "
393                          "0x%"HWADDR_PRIx") = %d (%m)",
394                          container, iova,
395                          iotlb->addr_mask + 1, ret);
396         }
397     }
398 out:
399     rcu_read_unlock();
400 }
401 
402 static void vfio_listener_region_add(MemoryListener *listener,
403                                      MemoryRegionSection *section)
404 {
405     VFIOContainer *container = container_of(listener, VFIOContainer, listener);
406     hwaddr iova, end;
407     Int128 llend, llsize;
408     void *vaddr;
409     int ret;
410     VFIOHostDMAWindow *hostwin;
411     bool hostwin_found;
412 
413     if (vfio_listener_skipped_section(section)) {
414         trace_vfio_listener_region_add_skip(
415                 section->offset_within_address_space,
416                 section->offset_within_address_space +
417                 int128_get64(int128_sub(section->size, int128_one())));
418         return;
419     }
420 
421     if (unlikely((section->offset_within_address_space & ~TARGET_PAGE_MASK) !=
422                  (section->offset_within_region & ~TARGET_PAGE_MASK))) {
423         error_report("%s received unaligned region", __func__);
424         return;
425     }
426 
427     iova = TARGET_PAGE_ALIGN(section->offset_within_address_space);
428     llend = int128_make64(section->offset_within_address_space);
429     llend = int128_add(llend, section->size);
430     llend = int128_and(llend, int128_exts64(TARGET_PAGE_MASK));
431 
432     if (int128_ge(int128_make64(iova), llend)) {
433         return;
434     }
435     end = int128_get64(int128_sub(llend, int128_one()));
436 
437     if (container->iommu_type == VFIO_SPAPR_TCE_v2_IOMMU) {
438         hwaddr pgsize = 0;
439 
440         /* For now intersections are not allowed, we may relax this later */
441         QLIST_FOREACH(hostwin, &container->hostwin_list, hostwin_next) {
442             if (ranges_overlap(hostwin->min_iova,
443                                hostwin->max_iova - hostwin->min_iova + 1,
444                                section->offset_within_address_space,
445                                int128_get64(section->size))) {
446                 ret = -1;
447                 goto fail;
448             }
449         }
450 
451         ret = vfio_spapr_create_window(container, section, &pgsize);
452         if (ret) {
453             goto fail;
454         }
455 
456         vfio_host_win_add(container, section->offset_within_address_space,
457                           section->offset_within_address_space +
458                           int128_get64(section->size) - 1, pgsize);
459 #ifdef CONFIG_KVM
460         if (kvm_enabled()) {
461             VFIOGroup *group;
462             IOMMUMemoryRegion *iommu_mr = IOMMU_MEMORY_REGION(section->mr);
463             struct kvm_vfio_spapr_tce param;
464             struct kvm_device_attr attr = {
465                 .group = KVM_DEV_VFIO_GROUP,
466                 .attr = KVM_DEV_VFIO_GROUP_SET_SPAPR_TCE,
467                 .addr = (uint64_t)(unsigned long)&param,
468             };
469 
470             if (!memory_region_iommu_get_attr(iommu_mr, IOMMU_ATTR_SPAPR_TCE_FD,
471                                               &param.tablefd)) {
472                 QLIST_FOREACH(group, &container->group_list, container_next) {
473                     param.groupfd = group->fd;
474                     if (ioctl(vfio_kvm_device_fd, KVM_SET_DEVICE_ATTR, &attr)) {
475                         error_report("vfio: failed to setup fd %d "
476                                      "for a group with fd %d: %s",
477                                      param.tablefd, param.groupfd,
478                                      strerror(errno));
479                         return;
480                     }
481                     trace_vfio_spapr_group_attach(param.groupfd, param.tablefd);
482                 }
483             }
484         }
485 #endif
486     }
487 
488     hostwin_found = false;
489     QLIST_FOREACH(hostwin, &container->hostwin_list, hostwin_next) {
490         if (hostwin->min_iova <= iova && end <= hostwin->max_iova) {
491             hostwin_found = true;
492             break;
493         }
494     }
495 
496     if (!hostwin_found) {
497         error_report("vfio: IOMMU container %p can't map guest IOVA region"
498                      " 0x%"HWADDR_PRIx"..0x%"HWADDR_PRIx,
499                      container, iova, end);
500         ret = -EFAULT;
501         goto fail;
502     }
503 
504     memory_region_ref(section->mr);
505 
506     if (memory_region_is_iommu(section->mr)) {
507         VFIOGuestIOMMU *giommu;
508         IOMMUMemoryRegion *iommu_mr = IOMMU_MEMORY_REGION(section->mr);
509 
510         trace_vfio_listener_region_add_iommu(iova, end);
511         /*
512          * FIXME: For VFIO iommu types which have KVM acceleration to
513          * avoid bouncing all map/unmaps through qemu this way, this
514          * would be the right place to wire that up (tell the KVM
515          * device emulation the VFIO iommu handles to use).
516          */
517         giommu = g_malloc0(sizeof(*giommu));
518         giommu->iommu = iommu_mr;
519         giommu->iommu_offset = section->offset_within_address_space -
520                                section->offset_within_region;
521         giommu->container = container;
522         llend = int128_add(int128_make64(section->offset_within_region),
523                            section->size);
524         llend = int128_sub(llend, int128_one());
525         iommu_notifier_init(&giommu->n, vfio_iommu_map_notify,
526                             IOMMU_NOTIFIER_ALL,
527                             section->offset_within_region,
528                             int128_get64(llend));
529         QLIST_INSERT_HEAD(&container->giommu_list, giommu, giommu_next);
530 
531         memory_region_register_iommu_notifier(section->mr, &giommu->n);
532         memory_region_iommu_replay(giommu->iommu, &giommu->n);
533 
534         return;
535     }
536 
537     /* Here we assume that memory_region_is_ram(section->mr)==true */
538 
539     vaddr = memory_region_get_ram_ptr(section->mr) +
540             section->offset_within_region +
541             (iova - section->offset_within_address_space);
542 
543     trace_vfio_listener_region_add_ram(iova, end, vaddr);
544 
545     llsize = int128_sub(llend, int128_make64(iova));
546 
547     if (memory_region_is_ram_device(section->mr)) {
548         hwaddr pgmask = (1ULL << ctz64(hostwin->iova_pgsizes)) - 1;
549 
550         if ((iova & pgmask) || (int128_get64(llsize) & pgmask)) {
551             error_report("Region 0x%"HWADDR_PRIx"..0x%"HWADDR_PRIx
552                          " is not aligned to 0x%"HWADDR_PRIx
553                          " and cannot be mapped for DMA",
554                          section->offset_within_region,
555                          int128_getlo(section->size),
556                          pgmask + 1);
557             return;
558         }
559     }
560 
561     ret = vfio_dma_map(container, iova, int128_get64(llsize),
562                        vaddr, section->readonly);
563     if (ret) {
564         error_report("vfio_dma_map(%p, 0x%"HWADDR_PRIx", "
565                      "0x%"HWADDR_PRIx", %p) = %d (%m)",
566                      container, iova, int128_get64(llsize), vaddr, ret);
567         if (memory_region_is_ram_device(section->mr)) {
568             /* Allow unexpected mappings not to be fatal for RAM devices */
569             return;
570         }
571         goto fail;
572     }
573 
574     return;
575 
576 fail:
577     if (memory_region_is_ram_device(section->mr)) {
578         error_report("failed to vfio_dma_map. pci p2p may not work");
579         return;
580     }
581     /*
582      * On the initfn path, store the first error in the container so we
583      * can gracefully fail.  Runtime, there's not much we can do other
584      * than throw a hardware error.
585      */
586     if (!container->initialized) {
587         if (!container->error) {
588             container->error = ret;
589         }
590     } else {
591         hw_error("vfio: DMA mapping failed, unable to continue");
592     }
593 }
594 
595 static void vfio_listener_region_del(MemoryListener *listener,
596                                      MemoryRegionSection *section)
597 {
598     VFIOContainer *container = container_of(listener, VFIOContainer, listener);
599     hwaddr iova, end;
600     Int128 llend, llsize;
601     int ret;
602     bool try_unmap = true;
603 
604     if (vfio_listener_skipped_section(section)) {
605         trace_vfio_listener_region_del_skip(
606                 section->offset_within_address_space,
607                 section->offset_within_address_space +
608                 int128_get64(int128_sub(section->size, int128_one())));
609         return;
610     }
611 
612     if (unlikely((section->offset_within_address_space & ~TARGET_PAGE_MASK) !=
613                  (section->offset_within_region & ~TARGET_PAGE_MASK))) {
614         error_report("%s received unaligned region", __func__);
615         return;
616     }
617 
618     if (memory_region_is_iommu(section->mr)) {
619         VFIOGuestIOMMU *giommu;
620 
621         QLIST_FOREACH(giommu, &container->giommu_list, giommu_next) {
622             if (MEMORY_REGION(giommu->iommu) == section->mr &&
623                 giommu->n.start == section->offset_within_region) {
624                 memory_region_unregister_iommu_notifier(section->mr,
625                                                         &giommu->n);
626                 QLIST_REMOVE(giommu, giommu_next);
627                 g_free(giommu);
628                 break;
629             }
630         }
631 
632         /*
633          * FIXME: We assume the one big unmap below is adequate to
634          * remove any individual page mappings in the IOMMU which
635          * might have been copied into VFIO. This works for a page table
636          * based IOMMU where a big unmap flattens a large range of IO-PTEs.
637          * That may not be true for all IOMMU types.
638          */
639     }
640 
641     iova = TARGET_PAGE_ALIGN(section->offset_within_address_space);
642     llend = int128_make64(section->offset_within_address_space);
643     llend = int128_add(llend, section->size);
644     llend = int128_and(llend, int128_exts64(TARGET_PAGE_MASK));
645 
646     if (int128_ge(int128_make64(iova), llend)) {
647         return;
648     }
649     end = int128_get64(int128_sub(llend, int128_one()));
650 
651     llsize = int128_sub(llend, int128_make64(iova));
652 
653     trace_vfio_listener_region_del(iova, end);
654 
655     if (memory_region_is_ram_device(section->mr)) {
656         hwaddr pgmask;
657         VFIOHostDMAWindow *hostwin;
658         bool hostwin_found = false;
659 
660         QLIST_FOREACH(hostwin, &container->hostwin_list, hostwin_next) {
661             if (hostwin->min_iova <= iova && end <= hostwin->max_iova) {
662                 hostwin_found = true;
663                 break;
664             }
665         }
666         assert(hostwin_found); /* or region_add() would have failed */
667 
668         pgmask = (1ULL << ctz64(hostwin->iova_pgsizes)) - 1;
669         try_unmap = !((iova & pgmask) || (int128_get64(llsize) & pgmask));
670     }
671 
672     if (try_unmap) {
673         ret = vfio_dma_unmap(container, iova, int128_get64(llsize));
674         if (ret) {
675             error_report("vfio_dma_unmap(%p, 0x%"HWADDR_PRIx", "
676                          "0x%"HWADDR_PRIx") = %d (%m)",
677                          container, iova, int128_get64(llsize), ret);
678         }
679     }
680 
681     memory_region_unref(section->mr);
682 
683     if (container->iommu_type == VFIO_SPAPR_TCE_v2_IOMMU) {
684         vfio_spapr_remove_window(container,
685                                  section->offset_within_address_space);
686         if (vfio_host_win_del(container,
687                               section->offset_within_address_space,
688                               section->offset_within_address_space +
689                               int128_get64(section->size) - 1) < 0) {
690             hw_error("%s: Cannot delete missing window at %"HWADDR_PRIx,
691                      __func__, section->offset_within_address_space);
692         }
693     }
694 }
695 
696 static const MemoryListener vfio_memory_listener = {
697     .region_add = vfio_listener_region_add,
698     .region_del = vfio_listener_region_del,
699 };
700 
701 static void vfio_listener_release(VFIOContainer *container)
702 {
703     memory_listener_unregister(&container->listener);
704     if (container->iommu_type == VFIO_SPAPR_TCE_v2_IOMMU) {
705         memory_listener_unregister(&container->prereg_listener);
706     }
707 }
708 
709 static struct vfio_info_cap_header *
710 vfio_get_region_info_cap(struct vfio_region_info *info, uint16_t id)
711 {
712     struct vfio_info_cap_header *hdr;
713     void *ptr = info;
714 
715     if (!(info->flags & VFIO_REGION_INFO_FLAG_CAPS)) {
716         return NULL;
717     }
718 
719     for (hdr = ptr + info->cap_offset; hdr != ptr; hdr = ptr + hdr->next) {
720         if (hdr->id == id) {
721             return hdr;
722         }
723     }
724 
725     return NULL;
726 }
727 
728 static int vfio_setup_region_sparse_mmaps(VFIORegion *region,
729                                           struct vfio_region_info *info)
730 {
731     struct vfio_info_cap_header *hdr;
732     struct vfio_region_info_cap_sparse_mmap *sparse;
733     int i, j;
734 
735     hdr = vfio_get_region_info_cap(info, VFIO_REGION_INFO_CAP_SPARSE_MMAP);
736     if (!hdr) {
737         return -ENODEV;
738     }
739 
740     sparse = container_of(hdr, struct vfio_region_info_cap_sparse_mmap, header);
741 
742     trace_vfio_region_sparse_mmap_header(region->vbasedev->name,
743                                          region->nr, sparse->nr_areas);
744 
745     region->mmaps = g_new0(VFIOMmap, sparse->nr_areas);
746 
747     for (i = 0, j = 0; i < sparse->nr_areas; i++) {
748         trace_vfio_region_sparse_mmap_entry(i, sparse->areas[i].offset,
749                                             sparse->areas[i].offset +
750                                             sparse->areas[i].size);
751 
752         if (sparse->areas[i].size) {
753             region->mmaps[j].offset = sparse->areas[i].offset;
754             region->mmaps[j].size = sparse->areas[i].size;
755             j++;
756         }
757     }
758 
759     region->nr_mmaps = j;
760     region->mmaps = g_realloc(region->mmaps, j * sizeof(VFIOMmap));
761 
762     return 0;
763 }
764 
765 int vfio_region_setup(Object *obj, VFIODevice *vbasedev, VFIORegion *region,
766                       int index, const char *name)
767 {
768     struct vfio_region_info *info;
769     int ret;
770 
771     ret = vfio_get_region_info(vbasedev, index, &info);
772     if (ret) {
773         return ret;
774     }
775 
776     region->vbasedev = vbasedev;
777     region->flags = info->flags;
778     region->size = info->size;
779     region->fd_offset = info->offset;
780     region->nr = index;
781 
782     if (region->size) {
783         region->mem = g_new0(MemoryRegion, 1);
784         memory_region_init_io(region->mem, obj, &vfio_region_ops,
785                               region, name, region->size);
786 
787         if (!vbasedev->no_mmap &&
788             region->flags & VFIO_REGION_INFO_FLAG_MMAP) {
789 
790             ret = vfio_setup_region_sparse_mmaps(region, info);
791 
792             if (ret) {
793                 region->nr_mmaps = 1;
794                 region->mmaps = g_new0(VFIOMmap, region->nr_mmaps);
795                 region->mmaps[0].offset = 0;
796                 region->mmaps[0].size = region->size;
797             }
798         }
799     }
800 
801     g_free(info);
802 
803     trace_vfio_region_setup(vbasedev->name, index, name,
804                             region->flags, region->fd_offset, region->size);
805     return 0;
806 }
807 
808 int vfio_region_mmap(VFIORegion *region)
809 {
810     int i, prot = 0;
811     char *name;
812 
813     if (!region->mem) {
814         return 0;
815     }
816 
817     prot |= region->flags & VFIO_REGION_INFO_FLAG_READ ? PROT_READ : 0;
818     prot |= region->flags & VFIO_REGION_INFO_FLAG_WRITE ? PROT_WRITE : 0;
819 
820     for (i = 0; i < region->nr_mmaps; i++) {
821         region->mmaps[i].mmap = mmap(NULL, region->mmaps[i].size, prot,
822                                      MAP_SHARED, region->vbasedev->fd,
823                                      region->fd_offset +
824                                      region->mmaps[i].offset);
825         if (region->mmaps[i].mmap == MAP_FAILED) {
826             int ret = -errno;
827 
828             trace_vfio_region_mmap_fault(memory_region_name(region->mem), i,
829                                          region->fd_offset +
830                                          region->mmaps[i].offset,
831                                          region->fd_offset +
832                                          region->mmaps[i].offset +
833                                          region->mmaps[i].size - 1, ret);
834 
835             region->mmaps[i].mmap = NULL;
836 
837             for (i--; i >= 0; i--) {
838                 memory_region_del_subregion(region->mem, &region->mmaps[i].mem);
839                 munmap(region->mmaps[i].mmap, region->mmaps[i].size);
840                 object_unparent(OBJECT(&region->mmaps[i].mem));
841                 region->mmaps[i].mmap = NULL;
842             }
843 
844             return ret;
845         }
846 
847         name = g_strdup_printf("%s mmaps[%d]",
848                                memory_region_name(region->mem), i);
849         memory_region_init_ram_device_ptr(&region->mmaps[i].mem,
850                                           memory_region_owner(region->mem),
851                                           name, region->mmaps[i].size,
852                                           region->mmaps[i].mmap);
853         g_free(name);
854         memory_region_add_subregion(region->mem, region->mmaps[i].offset,
855                                     &region->mmaps[i].mem);
856 
857         trace_vfio_region_mmap(memory_region_name(&region->mmaps[i].mem),
858                                region->mmaps[i].offset,
859                                region->mmaps[i].offset +
860                                region->mmaps[i].size - 1);
861     }
862 
863     return 0;
864 }
865 
866 void vfio_region_exit(VFIORegion *region)
867 {
868     int i;
869 
870     if (!region->mem) {
871         return;
872     }
873 
874     for (i = 0; i < region->nr_mmaps; i++) {
875         if (region->mmaps[i].mmap) {
876             memory_region_del_subregion(region->mem, &region->mmaps[i].mem);
877         }
878     }
879 
880     trace_vfio_region_exit(region->vbasedev->name, region->nr);
881 }
882 
883 void vfio_region_finalize(VFIORegion *region)
884 {
885     int i;
886 
887     if (!region->mem) {
888         return;
889     }
890 
891     for (i = 0; i < region->nr_mmaps; i++) {
892         if (region->mmaps[i].mmap) {
893             munmap(region->mmaps[i].mmap, region->mmaps[i].size);
894             object_unparent(OBJECT(&region->mmaps[i].mem));
895         }
896     }
897 
898     object_unparent(OBJECT(region->mem));
899 
900     g_free(region->mem);
901     g_free(region->mmaps);
902 
903     trace_vfio_region_finalize(region->vbasedev->name, region->nr);
904 
905     region->mem = NULL;
906     region->mmaps = NULL;
907     region->nr_mmaps = 0;
908     region->size = 0;
909     region->flags = 0;
910     region->nr = 0;
911 }
912 
913 void vfio_region_mmaps_set_enabled(VFIORegion *region, bool enabled)
914 {
915     int i;
916 
917     if (!region->mem) {
918         return;
919     }
920 
921     for (i = 0; i < region->nr_mmaps; i++) {
922         if (region->mmaps[i].mmap) {
923             memory_region_set_enabled(&region->mmaps[i].mem, enabled);
924         }
925     }
926 
927     trace_vfio_region_mmaps_set_enabled(memory_region_name(region->mem),
928                                         enabled);
929 }
930 
931 void vfio_reset_handler(void *opaque)
932 {
933     VFIOGroup *group;
934     VFIODevice *vbasedev;
935 
936     QLIST_FOREACH(group, &vfio_group_list, next) {
937         QLIST_FOREACH(vbasedev, &group->device_list, next) {
938             if (vbasedev->dev->realized) {
939                 vbasedev->ops->vfio_compute_needs_reset(vbasedev);
940             }
941         }
942     }
943 
944     QLIST_FOREACH(group, &vfio_group_list, next) {
945         QLIST_FOREACH(vbasedev, &group->device_list, next) {
946             if (vbasedev->dev->realized && vbasedev->needs_reset) {
947                 vbasedev->ops->vfio_hot_reset_multi(vbasedev);
948             }
949         }
950     }
951 }
952 
953 static void vfio_kvm_device_add_group(VFIOGroup *group)
954 {
955 #ifdef CONFIG_KVM
956     struct kvm_device_attr attr = {
957         .group = KVM_DEV_VFIO_GROUP,
958         .attr = KVM_DEV_VFIO_GROUP_ADD,
959         .addr = (uint64_t)(unsigned long)&group->fd,
960     };
961 
962     if (!kvm_enabled()) {
963         return;
964     }
965 
966     if (vfio_kvm_device_fd < 0) {
967         struct kvm_create_device cd = {
968             .type = KVM_DEV_TYPE_VFIO,
969         };
970 
971         if (kvm_vm_ioctl(kvm_state, KVM_CREATE_DEVICE, &cd)) {
972             error_report("Failed to create KVM VFIO device: %m");
973             return;
974         }
975 
976         vfio_kvm_device_fd = cd.fd;
977     }
978 
979     if (ioctl(vfio_kvm_device_fd, KVM_SET_DEVICE_ATTR, &attr)) {
980         error_report("Failed to add group %d to KVM VFIO device: %m",
981                      group->groupid);
982     }
983 #endif
984 }
985 
986 static void vfio_kvm_device_del_group(VFIOGroup *group)
987 {
988 #ifdef CONFIG_KVM
989     struct kvm_device_attr attr = {
990         .group = KVM_DEV_VFIO_GROUP,
991         .attr = KVM_DEV_VFIO_GROUP_DEL,
992         .addr = (uint64_t)(unsigned long)&group->fd,
993     };
994 
995     if (vfio_kvm_device_fd < 0) {
996         return;
997     }
998 
999     if (ioctl(vfio_kvm_device_fd, KVM_SET_DEVICE_ATTR, &attr)) {
1000         error_report("Failed to remove group %d from KVM VFIO device: %m",
1001                      group->groupid);
1002     }
1003 #endif
1004 }
1005 
1006 static VFIOAddressSpace *vfio_get_address_space(AddressSpace *as)
1007 {
1008     VFIOAddressSpace *space;
1009 
1010     QLIST_FOREACH(space, &vfio_address_spaces, list) {
1011         if (space->as == as) {
1012             return space;
1013         }
1014     }
1015 
1016     /* No suitable VFIOAddressSpace, create a new one */
1017     space = g_malloc0(sizeof(*space));
1018     space->as = as;
1019     QLIST_INIT(&space->containers);
1020 
1021     QLIST_INSERT_HEAD(&vfio_address_spaces, space, list);
1022 
1023     return space;
1024 }
1025 
1026 static void vfio_put_address_space(VFIOAddressSpace *space)
1027 {
1028     if (QLIST_EMPTY(&space->containers)) {
1029         QLIST_REMOVE(space, list);
1030         g_free(space);
1031     }
1032 }
1033 
1034 static int vfio_connect_container(VFIOGroup *group, AddressSpace *as,
1035                                   Error **errp)
1036 {
1037     VFIOContainer *container;
1038     int ret, fd;
1039     VFIOAddressSpace *space;
1040 
1041     space = vfio_get_address_space(as);
1042 
1043     QLIST_FOREACH(container, &space->containers, next) {
1044         if (!ioctl(group->fd, VFIO_GROUP_SET_CONTAINER, &container->fd)) {
1045             group->container = container;
1046             QLIST_INSERT_HEAD(&container->group_list, group, container_next);
1047             vfio_kvm_device_add_group(group);
1048             return 0;
1049         }
1050     }
1051 
1052     fd = qemu_open("/dev/vfio/vfio", O_RDWR);
1053     if (fd < 0) {
1054         error_setg_errno(errp, errno, "failed to open /dev/vfio/vfio");
1055         ret = -errno;
1056         goto put_space_exit;
1057     }
1058 
1059     ret = ioctl(fd, VFIO_GET_API_VERSION);
1060     if (ret != VFIO_API_VERSION) {
1061         error_setg(errp, "supported vfio version: %d, "
1062                    "reported version: %d", VFIO_API_VERSION, ret);
1063         ret = -EINVAL;
1064         goto close_fd_exit;
1065     }
1066 
1067     container = g_malloc0(sizeof(*container));
1068     container->space = space;
1069     container->fd = fd;
1070     QLIST_INIT(&container->giommu_list);
1071     QLIST_INIT(&container->hostwin_list);
1072     if (ioctl(fd, VFIO_CHECK_EXTENSION, VFIO_TYPE1_IOMMU) ||
1073         ioctl(fd, VFIO_CHECK_EXTENSION, VFIO_TYPE1v2_IOMMU)) {
1074         bool v2 = !!ioctl(fd, VFIO_CHECK_EXTENSION, VFIO_TYPE1v2_IOMMU);
1075         struct vfio_iommu_type1_info info;
1076 
1077         ret = ioctl(group->fd, VFIO_GROUP_SET_CONTAINER, &fd);
1078         if (ret) {
1079             error_setg_errno(errp, errno, "failed to set group container");
1080             ret = -errno;
1081             goto free_container_exit;
1082         }
1083 
1084         container->iommu_type = v2 ? VFIO_TYPE1v2_IOMMU : VFIO_TYPE1_IOMMU;
1085         ret = ioctl(fd, VFIO_SET_IOMMU, container->iommu_type);
1086         if (ret) {
1087             error_setg_errno(errp, errno, "failed to set iommu for container");
1088             ret = -errno;
1089             goto free_container_exit;
1090         }
1091 
1092         /*
1093          * FIXME: This assumes that a Type1 IOMMU can map any 64-bit
1094          * IOVA whatsoever.  That's not actually true, but the current
1095          * kernel interface doesn't tell us what it can map, and the
1096          * existing Type1 IOMMUs generally support any IOVA we're
1097          * going to actually try in practice.
1098          */
1099         info.argsz = sizeof(info);
1100         ret = ioctl(fd, VFIO_IOMMU_GET_INFO, &info);
1101         /* Ignore errors */
1102         if (ret || !(info.flags & VFIO_IOMMU_INFO_PGSIZES)) {
1103             /* Assume 4k IOVA page size */
1104             info.iova_pgsizes = 4096;
1105         }
1106         vfio_host_win_add(container, 0, (hwaddr)-1, info.iova_pgsizes);
1107     } else if (ioctl(fd, VFIO_CHECK_EXTENSION, VFIO_SPAPR_TCE_IOMMU) ||
1108                ioctl(fd, VFIO_CHECK_EXTENSION, VFIO_SPAPR_TCE_v2_IOMMU)) {
1109         struct vfio_iommu_spapr_tce_info info;
1110         bool v2 = !!ioctl(fd, VFIO_CHECK_EXTENSION, VFIO_SPAPR_TCE_v2_IOMMU);
1111 
1112         ret = ioctl(group->fd, VFIO_GROUP_SET_CONTAINER, &fd);
1113         if (ret) {
1114             error_setg_errno(errp, errno, "failed to set group container");
1115             ret = -errno;
1116             goto free_container_exit;
1117         }
1118         container->iommu_type =
1119             v2 ? VFIO_SPAPR_TCE_v2_IOMMU : VFIO_SPAPR_TCE_IOMMU;
1120         ret = ioctl(fd, VFIO_SET_IOMMU, container->iommu_type);
1121         if (ret) {
1122             container->iommu_type = VFIO_SPAPR_TCE_IOMMU;
1123             v2 = false;
1124             ret = ioctl(fd, VFIO_SET_IOMMU, container->iommu_type);
1125         }
1126         if (ret) {
1127             error_setg_errno(errp, errno, "failed to set iommu for container");
1128             ret = -errno;
1129             goto free_container_exit;
1130         }
1131 
1132         /*
1133          * The host kernel code implementing VFIO_IOMMU_DISABLE is called
1134          * when container fd is closed so we do not call it explicitly
1135          * in this file.
1136          */
1137         if (!v2) {
1138             ret = ioctl(fd, VFIO_IOMMU_ENABLE);
1139             if (ret) {
1140                 error_setg_errno(errp, errno, "failed to enable container");
1141                 ret = -errno;
1142                 goto free_container_exit;
1143             }
1144         } else {
1145             container->prereg_listener = vfio_prereg_listener;
1146 
1147             memory_listener_register(&container->prereg_listener,
1148                                      &address_space_memory);
1149             if (container->error) {
1150                 memory_listener_unregister(&container->prereg_listener);
1151                 ret = container->error;
1152                 error_setg(errp,
1153                     "RAM memory listener initialization failed for container");
1154                 goto free_container_exit;
1155             }
1156         }
1157 
1158         info.argsz = sizeof(info);
1159         ret = ioctl(fd, VFIO_IOMMU_SPAPR_TCE_GET_INFO, &info);
1160         if (ret) {
1161             error_setg_errno(errp, errno,
1162                              "VFIO_IOMMU_SPAPR_TCE_GET_INFO failed");
1163             ret = -errno;
1164             if (v2) {
1165                 memory_listener_unregister(&container->prereg_listener);
1166             }
1167             goto free_container_exit;
1168         }
1169 
1170         if (v2) {
1171             /*
1172              * There is a default window in just created container.
1173              * To make region_add/del simpler, we better remove this
1174              * window now and let those iommu_listener callbacks
1175              * create/remove them when needed.
1176              */
1177             ret = vfio_spapr_remove_window(container, info.dma32_window_start);
1178             if (ret) {
1179                 error_setg_errno(errp, -ret,
1180                                  "failed to remove existing window");
1181                 goto free_container_exit;
1182             }
1183         } else {
1184             /* The default table uses 4K pages */
1185             vfio_host_win_add(container, info.dma32_window_start,
1186                               info.dma32_window_start +
1187                               info.dma32_window_size - 1,
1188                               0x1000);
1189         }
1190     } else {
1191         error_setg(errp, "No available IOMMU models");
1192         ret = -EINVAL;
1193         goto free_container_exit;
1194     }
1195 
1196     vfio_kvm_device_add_group(group);
1197 
1198     QLIST_INIT(&container->group_list);
1199     QLIST_INSERT_HEAD(&space->containers, container, next);
1200 
1201     group->container = container;
1202     QLIST_INSERT_HEAD(&container->group_list, group, container_next);
1203 
1204     container->listener = vfio_memory_listener;
1205 
1206     memory_listener_register(&container->listener, container->space->as);
1207 
1208     if (container->error) {
1209         ret = container->error;
1210         error_setg_errno(errp, -ret,
1211                          "memory listener initialization failed for container");
1212         goto listener_release_exit;
1213     }
1214 
1215     container->initialized = true;
1216 
1217     return 0;
1218 listener_release_exit:
1219     QLIST_REMOVE(group, container_next);
1220     QLIST_REMOVE(container, next);
1221     vfio_kvm_device_del_group(group);
1222     vfio_listener_release(container);
1223 
1224 free_container_exit:
1225     g_free(container);
1226 
1227 close_fd_exit:
1228     close(fd);
1229 
1230 put_space_exit:
1231     vfio_put_address_space(space);
1232 
1233     return ret;
1234 }
1235 
1236 static void vfio_disconnect_container(VFIOGroup *group)
1237 {
1238     VFIOContainer *container = group->container;
1239 
1240     QLIST_REMOVE(group, container_next);
1241     group->container = NULL;
1242 
1243     /*
1244      * Explicitly release the listener first before unset container,
1245      * since unset may destroy the backend container if it's the last
1246      * group.
1247      */
1248     if (QLIST_EMPTY(&container->group_list)) {
1249         vfio_listener_release(container);
1250     }
1251 
1252     if (ioctl(group->fd, VFIO_GROUP_UNSET_CONTAINER, &container->fd)) {
1253         error_report("vfio: error disconnecting group %d from container",
1254                      group->groupid);
1255     }
1256 
1257     if (QLIST_EMPTY(&container->group_list)) {
1258         VFIOAddressSpace *space = container->space;
1259         VFIOGuestIOMMU *giommu, *tmp;
1260 
1261         QLIST_REMOVE(container, next);
1262 
1263         QLIST_FOREACH_SAFE(giommu, &container->giommu_list, giommu_next, tmp) {
1264             memory_region_unregister_iommu_notifier(
1265                     MEMORY_REGION(giommu->iommu), &giommu->n);
1266             QLIST_REMOVE(giommu, giommu_next);
1267             g_free(giommu);
1268         }
1269 
1270         trace_vfio_disconnect_container(container->fd);
1271         close(container->fd);
1272         g_free(container);
1273 
1274         vfio_put_address_space(space);
1275     }
1276 }
1277 
1278 VFIOGroup *vfio_get_group(int groupid, AddressSpace *as, Error **errp)
1279 {
1280     VFIOGroup *group;
1281     char path[32];
1282     struct vfio_group_status status = { .argsz = sizeof(status) };
1283 
1284     QLIST_FOREACH(group, &vfio_group_list, next) {
1285         if (group->groupid == groupid) {
1286             /* Found it.  Now is it already in the right context? */
1287             if (group->container->space->as == as) {
1288                 return group;
1289             } else {
1290                 error_setg(errp, "group %d used in multiple address spaces",
1291                            group->groupid);
1292                 return NULL;
1293             }
1294         }
1295     }
1296 
1297     group = g_malloc0(sizeof(*group));
1298 
1299     snprintf(path, sizeof(path), "/dev/vfio/%d", groupid);
1300     group->fd = qemu_open(path, O_RDWR);
1301     if (group->fd < 0) {
1302         error_setg_errno(errp, errno, "failed to open %s", path);
1303         goto free_group_exit;
1304     }
1305 
1306     if (ioctl(group->fd, VFIO_GROUP_GET_STATUS, &status)) {
1307         error_setg_errno(errp, errno, "failed to get group %d status", groupid);
1308         goto close_fd_exit;
1309     }
1310 
1311     if (!(status.flags & VFIO_GROUP_FLAGS_VIABLE)) {
1312         error_setg(errp, "group %d is not viable", groupid);
1313         error_append_hint(errp,
1314                           "Please ensure all devices within the iommu_group "
1315                           "are bound to their vfio bus driver.\n");
1316         goto close_fd_exit;
1317     }
1318 
1319     group->groupid = groupid;
1320     QLIST_INIT(&group->device_list);
1321 
1322     if (vfio_connect_container(group, as, errp)) {
1323         error_prepend(errp, "failed to setup container for group %d: ",
1324                       groupid);
1325         goto close_fd_exit;
1326     }
1327 
1328     if (QLIST_EMPTY(&vfio_group_list)) {
1329         qemu_register_reset(vfio_reset_handler, NULL);
1330     }
1331 
1332     QLIST_INSERT_HEAD(&vfio_group_list, group, next);
1333 
1334     return group;
1335 
1336 close_fd_exit:
1337     close(group->fd);
1338 
1339 free_group_exit:
1340     g_free(group);
1341 
1342     return NULL;
1343 }
1344 
1345 void vfio_put_group(VFIOGroup *group)
1346 {
1347     if (!group || !QLIST_EMPTY(&group->device_list)) {
1348         return;
1349     }
1350 
1351     vfio_kvm_device_del_group(group);
1352     vfio_disconnect_container(group);
1353     QLIST_REMOVE(group, next);
1354     trace_vfio_put_group(group->fd);
1355     close(group->fd);
1356     g_free(group);
1357 
1358     if (QLIST_EMPTY(&vfio_group_list)) {
1359         qemu_unregister_reset(vfio_reset_handler, NULL);
1360     }
1361 }
1362 
1363 int vfio_get_device(VFIOGroup *group, const char *name,
1364                     VFIODevice *vbasedev, Error **errp)
1365 {
1366     struct vfio_device_info dev_info = { .argsz = sizeof(dev_info) };
1367     int ret, fd;
1368 
1369     fd = ioctl(group->fd, VFIO_GROUP_GET_DEVICE_FD, name);
1370     if (fd < 0) {
1371         error_setg_errno(errp, errno, "error getting device from group %d",
1372                          group->groupid);
1373         error_append_hint(errp,
1374                       "Verify all devices in group %d are bound to vfio-<bus> "
1375                       "or pci-stub and not already in use\n", group->groupid);
1376         return fd;
1377     }
1378 
1379     ret = ioctl(fd, VFIO_DEVICE_GET_INFO, &dev_info);
1380     if (ret) {
1381         error_setg_errno(errp, errno, "error getting device info");
1382         close(fd);
1383         return ret;
1384     }
1385 
1386     vbasedev->fd = fd;
1387     vbasedev->group = group;
1388     QLIST_INSERT_HEAD(&group->device_list, vbasedev, next);
1389 
1390     vbasedev->num_irqs = dev_info.num_irqs;
1391     vbasedev->num_regions = dev_info.num_regions;
1392     vbasedev->flags = dev_info.flags;
1393 
1394     trace_vfio_get_device(name, dev_info.flags, dev_info.num_regions,
1395                           dev_info.num_irqs);
1396 
1397     vbasedev->reset_works = !!(dev_info.flags & VFIO_DEVICE_FLAGS_RESET);
1398     return 0;
1399 }
1400 
1401 void vfio_put_base_device(VFIODevice *vbasedev)
1402 {
1403     if (!vbasedev->group) {
1404         return;
1405     }
1406     QLIST_REMOVE(vbasedev, next);
1407     vbasedev->group = NULL;
1408     trace_vfio_put_base_device(vbasedev->fd);
1409     close(vbasedev->fd);
1410 }
1411 
1412 int vfio_get_region_info(VFIODevice *vbasedev, int index,
1413                          struct vfio_region_info **info)
1414 {
1415     size_t argsz = sizeof(struct vfio_region_info);
1416 
1417     *info = g_malloc0(argsz);
1418 
1419     (*info)->index = index;
1420 retry:
1421     (*info)->argsz = argsz;
1422 
1423     if (ioctl(vbasedev->fd, VFIO_DEVICE_GET_REGION_INFO, *info)) {
1424         g_free(*info);
1425         *info = NULL;
1426         return -errno;
1427     }
1428 
1429     if ((*info)->argsz > argsz) {
1430         argsz = (*info)->argsz;
1431         *info = g_realloc(*info, argsz);
1432 
1433         goto retry;
1434     }
1435 
1436     return 0;
1437 }
1438 
1439 int vfio_get_dev_region_info(VFIODevice *vbasedev, uint32_t type,
1440                              uint32_t subtype, struct vfio_region_info **info)
1441 {
1442     int i;
1443 
1444     for (i = 0; i < vbasedev->num_regions; i++) {
1445         struct vfio_info_cap_header *hdr;
1446         struct vfio_region_info_cap_type *cap_type;
1447 
1448         if (vfio_get_region_info(vbasedev, i, info)) {
1449             continue;
1450         }
1451 
1452         hdr = vfio_get_region_info_cap(*info, VFIO_REGION_INFO_CAP_TYPE);
1453         if (!hdr) {
1454             g_free(*info);
1455             continue;
1456         }
1457 
1458         cap_type = container_of(hdr, struct vfio_region_info_cap_type, header);
1459 
1460         trace_vfio_get_dev_region(vbasedev->name, i,
1461                                   cap_type->type, cap_type->subtype);
1462 
1463         if (cap_type->type == type && cap_type->subtype == subtype) {
1464             return 0;
1465         }
1466 
1467         g_free(*info);
1468     }
1469 
1470     *info = NULL;
1471     return -ENODEV;
1472 }
1473 
1474 bool vfio_has_region_cap(VFIODevice *vbasedev, int region, uint16_t cap_type)
1475 {
1476     struct vfio_region_info *info = NULL;
1477     bool ret = false;
1478 
1479     if (!vfio_get_region_info(vbasedev, region, &info)) {
1480         if (vfio_get_region_info_cap(info, cap_type)) {
1481             ret = true;
1482         }
1483         g_free(info);
1484     }
1485 
1486     return ret;
1487 }
1488 
1489 /*
1490  * Interfaces for IBM EEH (Enhanced Error Handling)
1491  */
1492 static bool vfio_eeh_container_ok(VFIOContainer *container)
1493 {
1494     /*
1495      * As of 2016-03-04 (linux-4.5) the host kernel EEH/VFIO
1496      * implementation is broken if there are multiple groups in a
1497      * container.  The hardware works in units of Partitionable
1498      * Endpoints (== IOMMU groups) and the EEH operations naively
1499      * iterate across all groups in the container, without any logic
1500      * to make sure the groups have their state synchronized.  For
1501      * certain operations (ENABLE) that might be ok, until an error
1502      * occurs, but for others (GET_STATE) it's clearly broken.
1503      */
1504 
1505     /*
1506      * XXX Once fixed kernels exist, test for them here
1507      */
1508 
1509     if (QLIST_EMPTY(&container->group_list)) {
1510         return false;
1511     }
1512 
1513     if (QLIST_NEXT(QLIST_FIRST(&container->group_list), container_next)) {
1514         return false;
1515     }
1516 
1517     return true;
1518 }
1519 
1520 static int vfio_eeh_container_op(VFIOContainer *container, uint32_t op)
1521 {
1522     struct vfio_eeh_pe_op pe_op = {
1523         .argsz = sizeof(pe_op),
1524         .op = op,
1525     };
1526     int ret;
1527 
1528     if (!vfio_eeh_container_ok(container)) {
1529         error_report("vfio/eeh: EEH_PE_OP 0x%x: "
1530                      "kernel requires a container with exactly one group", op);
1531         return -EPERM;
1532     }
1533 
1534     ret = ioctl(container->fd, VFIO_EEH_PE_OP, &pe_op);
1535     if (ret < 0) {
1536         error_report("vfio/eeh: EEH_PE_OP 0x%x failed: %m", op);
1537         return -errno;
1538     }
1539 
1540     return ret;
1541 }
1542 
1543 static VFIOContainer *vfio_eeh_as_container(AddressSpace *as)
1544 {
1545     VFIOAddressSpace *space = vfio_get_address_space(as);
1546     VFIOContainer *container = NULL;
1547 
1548     if (QLIST_EMPTY(&space->containers)) {
1549         /* No containers to act on */
1550         goto out;
1551     }
1552 
1553     container = QLIST_FIRST(&space->containers);
1554 
1555     if (QLIST_NEXT(container, next)) {
1556         /* We don't yet have logic to synchronize EEH state across
1557          * multiple containers */
1558         container = NULL;
1559         goto out;
1560     }
1561 
1562 out:
1563     vfio_put_address_space(space);
1564     return container;
1565 }
1566 
1567 bool vfio_eeh_as_ok(AddressSpace *as)
1568 {
1569     VFIOContainer *container = vfio_eeh_as_container(as);
1570 
1571     return (container != NULL) && vfio_eeh_container_ok(container);
1572 }
1573 
1574 int vfio_eeh_as_op(AddressSpace *as, uint32_t op)
1575 {
1576     VFIOContainer *container = vfio_eeh_as_container(as);
1577 
1578     if (!container) {
1579         return -ENODEV;
1580     }
1581     return vfio_eeh_container_op(container, op);
1582 }
1583