xref: /openbmc/qemu/hw/xen/xen_pt.c (revision a719a27c)
1 /*
2  * Copyright (c) 2007, Neocleus Corporation.
3  * Copyright (c) 2007, Intel Corporation.
4  *
5  * This work is licensed under the terms of the GNU GPL, version 2.  See
6  * the COPYING file in the top-level directory.
7  *
8  * Alex Novik <alex@neocleus.com>
9  * Allen Kay <allen.m.kay@intel.com>
10  * Guy Zana <guy@neocleus.com>
11  *
12  * This file implements direct PCI assignment to a HVM guest
13  */
14 
15 /*
16  * Interrupt Disable policy:
17  *
18  * INTx interrupt:
19  *   Initialize(register_real_device)
20  *     Map INTx(xc_physdev_map_pirq):
21  *       <fail>
22  *         - Set real Interrupt Disable bit to '1'.
23  *         - Set machine_irq and assigned_device->machine_irq to '0'.
24  *         * Don't bind INTx.
25  *
26  *     Bind INTx(xc_domain_bind_pt_pci_irq):
27  *       <fail>
28  *         - Set real Interrupt Disable bit to '1'.
29  *         - Unmap INTx.
30  *         - Decrement xen_pt_mapped_machine_irq[machine_irq]
31  *         - Set assigned_device->machine_irq to '0'.
32  *
33  *   Write to Interrupt Disable bit by guest software(xen_pt_cmd_reg_write)
34  *     Write '0'
35  *       - Set real bit to '0' if assigned_device->machine_irq isn't '0'.
36  *
37  *     Write '1'
38  *       - Set real bit to '1'.
39  *
40  * MSI interrupt:
41  *   Initialize MSI register(xen_pt_msi_setup, xen_pt_msi_update)
42  *     Bind MSI(xc_domain_update_msi_irq)
43  *       <fail>
44  *         - Unmap MSI.
45  *         - Set dev->msi->pirq to '-1'.
46  *
47  * MSI-X interrupt:
48  *   Initialize MSI-X register(xen_pt_msix_update_one)
49  *     Bind MSI-X(xc_domain_update_msi_irq)
50  *       <fail>
51  *         - Unmap MSI-X.
52  *         - Set entry->pirq to '-1'.
53  */
54 
55 #include <sys/ioctl.h>
56 
57 #include "hw/pci/pci.h"
58 #include "hw/xen/xen.h"
59 #include "hw/xen/xen_backend.h"
60 #include "xen_pt.h"
61 #include "qemu/range.h"
62 #include "exec/address-spaces.h"
63 
64 #define XEN_PT_NR_IRQS (256)
65 static uint8_t xen_pt_mapped_machine_irq[XEN_PT_NR_IRQS] = {0};
66 
67 void xen_pt_log(const PCIDevice *d, const char *f, ...)
68 {
69     va_list ap;
70 
71     va_start(ap, f);
72     if (d) {
73         fprintf(stderr, "[%02x:%02x.%d] ", pci_bus_num(d->bus),
74                 PCI_SLOT(d->devfn), PCI_FUNC(d->devfn));
75     }
76     vfprintf(stderr, f, ap);
77     va_end(ap);
78 }
79 
80 /* Config Space */
81 
82 static int xen_pt_pci_config_access_check(PCIDevice *d, uint32_t addr, int len)
83 {
84     /* check offset range */
85     if (addr >= 0xFF) {
86         XEN_PT_ERR(d, "Failed to access register with offset exceeding 0xFF. "
87                    "(addr: 0x%02x, len: %d)\n", addr, len);
88         return -1;
89     }
90 
91     /* check read size */
92     if ((len != 1) && (len != 2) && (len != 4)) {
93         XEN_PT_ERR(d, "Failed to access register with invalid access length. "
94                    "(addr: 0x%02x, len: %d)\n", addr, len);
95         return -1;
96     }
97 
98     /* check offset alignment */
99     if (addr & (len - 1)) {
100         XEN_PT_ERR(d, "Failed to access register with invalid access size "
101                    "alignment. (addr: 0x%02x, len: %d)\n", addr, len);
102         return -1;
103     }
104 
105     return 0;
106 }
107 
108 int xen_pt_bar_offset_to_index(uint32_t offset)
109 {
110     int index = 0;
111 
112     /* check Exp ROM BAR */
113     if (offset == PCI_ROM_ADDRESS) {
114         return PCI_ROM_SLOT;
115     }
116 
117     /* calculate BAR index */
118     index = (offset - PCI_BASE_ADDRESS_0) >> 2;
119     if (index >= PCI_NUM_REGIONS) {
120         return -1;
121     }
122 
123     return index;
124 }
125 
126 static uint32_t xen_pt_pci_read_config(PCIDevice *d, uint32_t addr, int len)
127 {
128     XenPCIPassthroughState *s = DO_UPCAST(XenPCIPassthroughState, dev, d);
129     uint32_t val = 0;
130     XenPTRegGroup *reg_grp_entry = NULL;
131     XenPTReg *reg_entry = NULL;
132     int rc = 0;
133     int emul_len = 0;
134     uint32_t find_addr = addr;
135 
136     if (xen_pt_pci_config_access_check(d, addr, len)) {
137         goto exit;
138     }
139 
140     /* find register group entry */
141     reg_grp_entry = xen_pt_find_reg_grp(s, addr);
142     if (reg_grp_entry) {
143         /* check 0-Hardwired register group */
144         if (reg_grp_entry->reg_grp->grp_type == XEN_PT_GRP_TYPE_HARDWIRED) {
145             /* no need to emulate, just return 0 */
146             val = 0;
147             goto exit;
148         }
149     }
150 
151     /* read I/O device register value */
152     rc = xen_host_pci_get_block(&s->real_device, addr, (uint8_t *)&val, len);
153     if (rc < 0) {
154         XEN_PT_ERR(d, "pci_read_block failed. return value: %d.\n", rc);
155         memset(&val, 0xff, len);
156     }
157 
158     /* just return the I/O device register value for
159      * passthrough type register group */
160     if (reg_grp_entry == NULL) {
161         goto exit;
162     }
163 
164     /* adjust the read value to appropriate CFC-CFF window */
165     val <<= (addr & 3) << 3;
166     emul_len = len;
167 
168     /* loop around the guest requested size */
169     while (emul_len > 0) {
170         /* find register entry to be emulated */
171         reg_entry = xen_pt_find_reg(reg_grp_entry, find_addr);
172         if (reg_entry) {
173             XenPTRegInfo *reg = reg_entry->reg;
174             uint32_t real_offset = reg_grp_entry->base_offset + reg->offset;
175             uint32_t valid_mask = 0xFFFFFFFF >> ((4 - emul_len) << 3);
176             uint8_t *ptr_val = NULL;
177 
178             valid_mask <<= (find_addr - real_offset) << 3;
179             ptr_val = (uint8_t *)&val + (real_offset & 3);
180 
181             /* do emulation based on register size */
182             switch (reg->size) {
183             case 1:
184                 if (reg->u.b.read) {
185                     rc = reg->u.b.read(s, reg_entry, ptr_val, valid_mask);
186                 }
187                 break;
188             case 2:
189                 if (reg->u.w.read) {
190                     rc = reg->u.w.read(s, reg_entry,
191                                        (uint16_t *)ptr_val, valid_mask);
192                 }
193                 break;
194             case 4:
195                 if (reg->u.dw.read) {
196                     rc = reg->u.dw.read(s, reg_entry,
197                                         (uint32_t *)ptr_val, valid_mask);
198                 }
199                 break;
200             }
201 
202             if (rc < 0) {
203                 xen_shutdown_fatal_error("Internal error: Invalid read "
204                                          "emulation. (%s, rc: %d)\n",
205                                          __func__, rc);
206                 return 0;
207             }
208 
209             /* calculate next address to find */
210             emul_len -= reg->size;
211             if (emul_len > 0) {
212                 find_addr = real_offset + reg->size;
213             }
214         } else {
215             /* nothing to do with passthrough type register,
216              * continue to find next byte */
217             emul_len--;
218             find_addr++;
219         }
220     }
221 
222     /* need to shift back before returning them to pci bus emulator */
223     val >>= ((addr & 3) << 3);
224 
225 exit:
226     XEN_PT_LOG_CONFIG(d, addr, val, len);
227     return val;
228 }
229 
230 static void xen_pt_pci_write_config(PCIDevice *d, uint32_t addr,
231                                     uint32_t val, int len)
232 {
233     XenPCIPassthroughState *s = DO_UPCAST(XenPCIPassthroughState, dev, d);
234     int index = 0;
235     XenPTRegGroup *reg_grp_entry = NULL;
236     int rc = 0;
237     uint32_t read_val = 0;
238     int emul_len = 0;
239     XenPTReg *reg_entry = NULL;
240     uint32_t find_addr = addr;
241     XenPTRegInfo *reg = NULL;
242 
243     if (xen_pt_pci_config_access_check(d, addr, len)) {
244         return;
245     }
246 
247     XEN_PT_LOG_CONFIG(d, addr, val, len);
248 
249     /* check unused BAR register */
250     index = xen_pt_bar_offset_to_index(addr);
251     if ((index >= 0) && (val > 0 && val < XEN_PT_BAR_ALLF) &&
252         (s->bases[index].bar_flag == XEN_PT_BAR_FLAG_UNUSED)) {
253         XEN_PT_WARN(d, "Guest attempt to set address to unused Base Address "
254                     "Register. (addr: 0x%02x, len: %d)\n", addr, len);
255     }
256 
257     /* find register group entry */
258     reg_grp_entry = xen_pt_find_reg_grp(s, addr);
259     if (reg_grp_entry) {
260         /* check 0-Hardwired register group */
261         if (reg_grp_entry->reg_grp->grp_type == XEN_PT_GRP_TYPE_HARDWIRED) {
262             /* ignore silently */
263             XEN_PT_WARN(d, "Access to 0-Hardwired register. "
264                         "(addr: 0x%02x, len: %d)\n", addr, len);
265             return;
266         }
267     }
268 
269     rc = xen_host_pci_get_block(&s->real_device, addr,
270                                 (uint8_t *)&read_val, len);
271     if (rc < 0) {
272         XEN_PT_ERR(d, "pci_read_block failed. return value: %d.\n", rc);
273         memset(&read_val, 0xff, len);
274     }
275 
276     /* pass directly to the real device for passthrough type register group */
277     if (reg_grp_entry == NULL) {
278         goto out;
279     }
280 
281     memory_region_transaction_begin();
282     pci_default_write_config(d, addr, val, len);
283 
284     /* adjust the read and write value to appropriate CFC-CFF window */
285     read_val <<= (addr & 3) << 3;
286     val <<= (addr & 3) << 3;
287     emul_len = len;
288 
289     /* loop around the guest requested size */
290     while (emul_len > 0) {
291         /* find register entry to be emulated */
292         reg_entry = xen_pt_find_reg(reg_grp_entry, find_addr);
293         if (reg_entry) {
294             reg = reg_entry->reg;
295             uint32_t real_offset = reg_grp_entry->base_offset + reg->offset;
296             uint32_t valid_mask = 0xFFFFFFFF >> ((4 - emul_len) << 3);
297             uint8_t *ptr_val = NULL;
298 
299             valid_mask <<= (find_addr - real_offset) << 3;
300             ptr_val = (uint8_t *)&val + (real_offset & 3);
301 
302             /* do emulation based on register size */
303             switch (reg->size) {
304             case 1:
305                 if (reg->u.b.write) {
306                     rc = reg->u.b.write(s, reg_entry, ptr_val,
307                                         read_val >> ((real_offset & 3) << 3),
308                                         valid_mask);
309                 }
310                 break;
311             case 2:
312                 if (reg->u.w.write) {
313                     rc = reg->u.w.write(s, reg_entry, (uint16_t *)ptr_val,
314                                         (read_val >> ((real_offset & 3) << 3)),
315                                         valid_mask);
316                 }
317                 break;
318             case 4:
319                 if (reg->u.dw.write) {
320                     rc = reg->u.dw.write(s, reg_entry, (uint32_t *)ptr_val,
321                                          (read_val >> ((real_offset & 3) << 3)),
322                                          valid_mask);
323                 }
324                 break;
325             }
326 
327             if (rc < 0) {
328                 xen_shutdown_fatal_error("Internal error: Invalid write"
329                                          " emulation. (%s, rc: %d)\n",
330                                          __func__, rc);
331                 return;
332             }
333 
334             /* calculate next address to find */
335             emul_len -= reg->size;
336             if (emul_len > 0) {
337                 find_addr = real_offset + reg->size;
338             }
339         } else {
340             /* nothing to do with passthrough type register,
341              * continue to find next byte */
342             emul_len--;
343             find_addr++;
344         }
345     }
346 
347     /* need to shift back before passing them to xen_host_pci_device */
348     val >>= (addr & 3) << 3;
349 
350     memory_region_transaction_commit();
351 
352 out:
353     if (!(reg && reg->no_wb)) {
354         /* unknown regs are passed through */
355         rc = xen_host_pci_set_block(&s->real_device, addr,
356                                     (uint8_t *)&val, len);
357 
358         if (rc < 0) {
359             XEN_PT_ERR(d, "pci_write_block failed. return value: %d.\n", rc);
360         }
361     }
362 }
363 
364 /* register regions */
365 
366 static uint64_t xen_pt_bar_read(void *o, hwaddr addr,
367                                 unsigned size)
368 {
369     PCIDevice *d = o;
370     /* if this function is called, that probably means that there is a
371      * misconfiguration of the IOMMU. */
372     XEN_PT_ERR(d, "Should not read BAR through QEMU. @0x"TARGET_FMT_plx"\n",
373                addr);
374     return 0;
375 }
376 static void xen_pt_bar_write(void *o, hwaddr addr, uint64_t val,
377                              unsigned size)
378 {
379     PCIDevice *d = o;
380     /* Same comment as xen_pt_bar_read function */
381     XEN_PT_ERR(d, "Should not write BAR through QEMU. @0x"TARGET_FMT_plx"\n",
382                addr);
383 }
384 
385 static const MemoryRegionOps ops = {
386     .endianness = DEVICE_NATIVE_ENDIAN,
387     .read = xen_pt_bar_read,
388     .write = xen_pt_bar_write,
389 };
390 
391 static int xen_pt_register_regions(XenPCIPassthroughState *s)
392 {
393     int i = 0;
394     XenHostPCIDevice *d = &s->real_device;
395 
396     /* Register PIO/MMIO BARs */
397     for (i = 0; i < PCI_ROM_SLOT; i++) {
398         XenHostPCIIORegion *r = &d->io_regions[i];
399         uint8_t type;
400 
401         if (r->base_addr == 0 || r->size == 0) {
402             continue;
403         }
404 
405         s->bases[i].access.u = r->base_addr;
406 
407         if (r->type & XEN_HOST_PCI_REGION_TYPE_IO) {
408             type = PCI_BASE_ADDRESS_SPACE_IO;
409         } else {
410             type = PCI_BASE_ADDRESS_SPACE_MEMORY;
411             if (r->type & XEN_HOST_PCI_REGION_TYPE_PREFETCH) {
412                 type |= PCI_BASE_ADDRESS_MEM_PREFETCH;
413             }
414             if (r->type & XEN_HOST_PCI_REGION_TYPE_MEM_64) {
415                 type |= PCI_BASE_ADDRESS_MEM_TYPE_64;
416             }
417         }
418 
419         memory_region_init_io(&s->bar[i], OBJECT(s), &ops, &s->dev,
420                               "xen-pci-pt-bar", r->size);
421         pci_register_bar(&s->dev, i, type, &s->bar[i]);
422 
423         XEN_PT_LOG(&s->dev, "IO region %i registered (size=0x%08"PRIx64
424                    " base_addr=0x%08"PRIx64" type: %#x)\n",
425                    i, r->size, r->base_addr, type);
426     }
427 
428     /* Register expansion ROM address */
429     if (d->rom.base_addr && d->rom.size) {
430         uint32_t bar_data = 0;
431 
432         /* Re-set BAR reported by OS, otherwise ROM can't be read. */
433         if (xen_host_pci_get_long(d, PCI_ROM_ADDRESS, &bar_data)) {
434             return 0;
435         }
436         if ((bar_data & PCI_ROM_ADDRESS_MASK) == 0) {
437             bar_data |= d->rom.base_addr & PCI_ROM_ADDRESS_MASK;
438             xen_host_pci_set_long(d, PCI_ROM_ADDRESS, bar_data);
439         }
440 
441         s->bases[PCI_ROM_SLOT].access.maddr = d->rom.base_addr;
442 
443         memory_region_init_io(&s->rom, OBJECT(s), &ops, &s->dev,
444                               "xen-pci-pt-rom", d->rom.size);
445         pci_register_bar(&s->dev, PCI_ROM_SLOT, PCI_BASE_ADDRESS_MEM_PREFETCH,
446                          &s->rom);
447 
448         XEN_PT_LOG(&s->dev, "Expansion ROM registered (size=0x%08"PRIx64
449                    " base_addr=0x%08"PRIx64")\n",
450                    d->rom.size, d->rom.base_addr);
451     }
452 
453     return 0;
454 }
455 
456 static void xen_pt_unregister_regions(XenPCIPassthroughState *s)
457 {
458     XenHostPCIDevice *d = &s->real_device;
459     int i;
460 
461     for (i = 0; i < PCI_NUM_REGIONS - 1; i++) {
462         XenHostPCIIORegion *r = &d->io_regions[i];
463 
464         if (r->base_addr == 0 || r->size == 0) {
465             continue;
466         }
467 
468         memory_region_destroy(&s->bar[i]);
469     }
470     if (d->rom.base_addr && d->rom.size) {
471         memory_region_destroy(&s->rom);
472     }
473 }
474 
475 /* region mapping */
476 
477 static int xen_pt_bar_from_region(XenPCIPassthroughState *s, MemoryRegion *mr)
478 {
479     int i = 0;
480 
481     for (i = 0; i < PCI_NUM_REGIONS - 1; i++) {
482         if (mr == &s->bar[i]) {
483             return i;
484         }
485     }
486     if (mr == &s->rom) {
487         return PCI_ROM_SLOT;
488     }
489     return -1;
490 }
491 
492 /*
493  * This function checks if an io_region overlaps an io_region from another
494  * device.  The io_region to check is provided with (addr, size and type)
495  * A callback can be provided and will be called for every region that is
496  * overlapped.
497  * The return value indicates if the region is overlappsed */
498 struct CheckBarArgs {
499     XenPCIPassthroughState *s;
500     pcibus_t addr;
501     pcibus_t size;
502     uint8_t type;
503     bool rc;
504 };
505 static void xen_pt_check_bar_overlap(PCIBus *bus, PCIDevice *d, void *opaque)
506 {
507     struct CheckBarArgs *arg = opaque;
508     XenPCIPassthroughState *s = arg->s;
509     uint8_t type = arg->type;
510     int i;
511 
512     if (d->devfn == s->dev.devfn) {
513         return;
514     }
515 
516     /* xxx: This ignores bridges. */
517     for (i = 0; i < PCI_NUM_REGIONS; i++) {
518         const PCIIORegion *r = &d->io_regions[i];
519 
520         if (!r->size) {
521             continue;
522         }
523         if ((type & PCI_BASE_ADDRESS_SPACE_IO)
524             != (r->type & PCI_BASE_ADDRESS_SPACE_IO)) {
525             continue;
526         }
527 
528         if (ranges_overlap(arg->addr, arg->size, r->addr, r->size)) {
529             XEN_PT_WARN(&s->dev,
530                         "Overlapped to device [%02x:%02x.%d] Region: %i"
531                         " (addr: %#"FMT_PCIBUS", len: %#"FMT_PCIBUS")\n",
532                         pci_bus_num(bus), PCI_SLOT(d->devfn),
533                         PCI_FUNC(d->devfn), i, r->addr, r->size);
534             arg->rc = true;
535         }
536     }
537 }
538 
539 static void xen_pt_region_update(XenPCIPassthroughState *s,
540                                  MemoryRegionSection *sec, bool adding)
541 {
542     PCIDevice *d = &s->dev;
543     MemoryRegion *mr = sec->mr;
544     int bar = -1;
545     int rc;
546     int op = adding ? DPCI_ADD_MAPPING : DPCI_REMOVE_MAPPING;
547     struct CheckBarArgs args = {
548         .s = s,
549         .addr = sec->offset_within_address_space,
550         .size = int128_get64(sec->size),
551         .rc = false,
552     };
553 
554     bar = xen_pt_bar_from_region(s, mr);
555     if (bar == -1 && (!s->msix || &s->msix->mmio != mr)) {
556         return;
557     }
558 
559     if (s->msix && &s->msix->mmio == mr) {
560         if (adding) {
561             s->msix->mmio_base_addr = sec->offset_within_address_space;
562             rc = xen_pt_msix_update_remap(s, s->msix->bar_index);
563         }
564         return;
565     }
566 
567     args.type = d->io_regions[bar].type;
568     pci_for_each_device(d->bus, pci_bus_num(d->bus),
569                         xen_pt_check_bar_overlap, &args);
570     if (args.rc) {
571         XEN_PT_WARN(d, "Region: %d (addr: %#"FMT_PCIBUS
572                     ", len: %#"FMT_PCIBUS") is overlapped.\n",
573                     bar, sec->offset_within_address_space,
574                     int128_get64(sec->size));
575     }
576 
577     if (d->io_regions[bar].type & PCI_BASE_ADDRESS_SPACE_IO) {
578         uint32_t guest_port = sec->offset_within_address_space;
579         uint32_t machine_port = s->bases[bar].access.pio_base;
580         uint32_t size = int128_get64(sec->size);
581         rc = xc_domain_ioport_mapping(xen_xc, xen_domid,
582                                       guest_port, machine_port, size,
583                                       op);
584         if (rc) {
585             XEN_PT_ERR(d, "%s ioport mapping failed! (rc: %i)\n",
586                        adding ? "create new" : "remove old", rc);
587         }
588     } else {
589         pcibus_t guest_addr = sec->offset_within_address_space;
590         pcibus_t machine_addr = s->bases[bar].access.maddr
591             + sec->offset_within_region;
592         pcibus_t size = int128_get64(sec->size);
593         rc = xc_domain_memory_mapping(xen_xc, xen_domid,
594                                       XEN_PFN(guest_addr + XC_PAGE_SIZE - 1),
595                                       XEN_PFN(machine_addr + XC_PAGE_SIZE - 1),
596                                       XEN_PFN(size + XC_PAGE_SIZE - 1),
597                                       op);
598         if (rc) {
599             XEN_PT_ERR(d, "%s mem mapping failed! (rc: %i)\n",
600                        adding ? "create new" : "remove old", rc);
601         }
602     }
603 }
604 
605 static void xen_pt_region_add(MemoryListener *l, MemoryRegionSection *sec)
606 {
607     XenPCIPassthroughState *s = container_of(l, XenPCIPassthroughState,
608                                              memory_listener);
609 
610     memory_region_ref(sec->mr);
611     xen_pt_region_update(s, sec, true);
612 }
613 
614 static void xen_pt_region_del(MemoryListener *l, MemoryRegionSection *sec)
615 {
616     XenPCIPassthroughState *s = container_of(l, XenPCIPassthroughState,
617                                              memory_listener);
618 
619     xen_pt_region_update(s, sec, false);
620     memory_region_unref(sec->mr);
621 }
622 
623 static void xen_pt_io_region_add(MemoryListener *l, MemoryRegionSection *sec)
624 {
625     XenPCIPassthroughState *s = container_of(l, XenPCIPassthroughState,
626                                              io_listener);
627 
628     memory_region_ref(sec->mr);
629     xen_pt_region_update(s, sec, true);
630 }
631 
632 static void xen_pt_io_region_del(MemoryListener *l, MemoryRegionSection *sec)
633 {
634     XenPCIPassthroughState *s = container_of(l, XenPCIPassthroughState,
635                                              io_listener);
636 
637     xen_pt_region_update(s, sec, false);
638     memory_region_unref(sec->mr);
639 }
640 
641 static const MemoryListener xen_pt_memory_listener = {
642     .region_add = xen_pt_region_add,
643     .region_del = xen_pt_region_del,
644     .priority = 10,
645 };
646 
647 static const MemoryListener xen_pt_io_listener = {
648     .region_add = xen_pt_io_region_add,
649     .region_del = xen_pt_io_region_del,
650     .priority = 10,
651 };
652 
653 /* init */
654 
655 static int xen_pt_initfn(PCIDevice *d)
656 {
657     XenPCIPassthroughState *s = DO_UPCAST(XenPCIPassthroughState, dev, d);
658     int rc = 0;
659     uint8_t machine_irq = 0;
660     int pirq = XEN_PT_UNASSIGNED_PIRQ;
661 
662     /* register real device */
663     XEN_PT_LOG(d, "Assigning real physical device %02x:%02x.%d"
664                " to devfn %#x\n",
665                s->hostaddr.bus, s->hostaddr.slot, s->hostaddr.function,
666                s->dev.devfn);
667 
668     rc = xen_host_pci_device_get(&s->real_device,
669                                  s->hostaddr.domain, s->hostaddr.bus,
670                                  s->hostaddr.slot, s->hostaddr.function);
671     if (rc) {
672         XEN_PT_ERR(d, "Failed to \"open\" the real pci device. rc: %i\n", rc);
673         return -1;
674     }
675 
676     s->is_virtfn = s->real_device.is_virtfn;
677     if (s->is_virtfn) {
678         XEN_PT_LOG(d, "%04x:%02x:%02x.%d is a SR-IOV Virtual Function\n",
679                    s->real_device.domain, s->real_device.bus,
680                    s->real_device.dev, s->real_device.func);
681     }
682 
683     /* Initialize virtualized PCI configuration (Extended 256 Bytes) */
684     if (xen_host_pci_get_block(&s->real_device, 0, d->config,
685                                PCI_CONFIG_SPACE_SIZE) == -1) {
686         xen_host_pci_device_put(&s->real_device);
687         return -1;
688     }
689 
690     s->memory_listener = xen_pt_memory_listener;
691     s->io_listener = xen_pt_io_listener;
692 
693     /* Handle real device's MMIO/PIO BARs */
694     xen_pt_register_regions(s);
695 
696     /* reinitialize each config register to be emulated */
697     if (xen_pt_config_init(s)) {
698         XEN_PT_ERR(d, "PCI Config space initialisation failed.\n");
699         xen_host_pci_device_put(&s->real_device);
700         return -1;
701     }
702 
703     /* Bind interrupt */
704     if (!s->dev.config[PCI_INTERRUPT_PIN]) {
705         XEN_PT_LOG(d, "no pin interrupt\n");
706         goto out;
707     }
708 
709     machine_irq = s->real_device.irq;
710     rc = xc_physdev_map_pirq(xen_xc, xen_domid, machine_irq, &pirq);
711 
712     if (rc < 0) {
713         XEN_PT_ERR(d, "Mapping machine irq %u to pirq %i failed, (rc: %d)\n",
714                    machine_irq, pirq, rc);
715 
716         /* Disable PCI intx assertion (turn on bit10 of devctl) */
717         xen_host_pci_set_word(&s->real_device,
718                               PCI_COMMAND,
719                               pci_get_word(s->dev.config + PCI_COMMAND)
720                               | PCI_COMMAND_INTX_DISABLE);
721         machine_irq = 0;
722         s->machine_irq = 0;
723     } else {
724         machine_irq = pirq;
725         s->machine_irq = pirq;
726         xen_pt_mapped_machine_irq[machine_irq]++;
727     }
728 
729     /* bind machine_irq to device */
730     if (machine_irq != 0) {
731         uint8_t e_intx = xen_pt_pci_intx(s);
732 
733         rc = xc_domain_bind_pt_pci_irq(xen_xc, xen_domid, machine_irq,
734                                        pci_bus_num(d->bus),
735                                        PCI_SLOT(d->devfn),
736                                        e_intx);
737         if (rc < 0) {
738             XEN_PT_ERR(d, "Binding of interrupt %i failed! (rc: %d)\n",
739                        e_intx, rc);
740 
741             /* Disable PCI intx assertion (turn on bit10 of devctl) */
742             xen_host_pci_set_word(&s->real_device, PCI_COMMAND,
743                                   *(uint16_t *)(&s->dev.config[PCI_COMMAND])
744                                   | PCI_COMMAND_INTX_DISABLE);
745             xen_pt_mapped_machine_irq[machine_irq]--;
746 
747             if (xen_pt_mapped_machine_irq[machine_irq] == 0) {
748                 if (xc_physdev_unmap_pirq(xen_xc, xen_domid, machine_irq)) {
749                     XEN_PT_ERR(d, "Unmapping of machine interrupt %i failed!"
750                                " (rc: %d)\n", machine_irq, rc);
751                 }
752             }
753             s->machine_irq = 0;
754         }
755     }
756 
757 out:
758     memory_listener_register(&s->memory_listener, &address_space_memory);
759     memory_listener_register(&s->io_listener, &address_space_io);
760     XEN_PT_LOG(d,
761                "Real physical device %02x:%02x.%d registered successfully!\n",
762                s->hostaddr.bus, s->hostaddr.slot, s->hostaddr.function);
763 
764     return 0;
765 }
766 
767 static void xen_pt_unregister_device(PCIDevice *d)
768 {
769     XenPCIPassthroughState *s = DO_UPCAST(XenPCIPassthroughState, dev, d);
770     uint8_t machine_irq = s->machine_irq;
771     uint8_t intx = xen_pt_pci_intx(s);
772     int rc;
773 
774     if (machine_irq) {
775         rc = xc_domain_unbind_pt_irq(xen_xc, xen_domid, machine_irq,
776                                      PT_IRQ_TYPE_PCI,
777                                      pci_bus_num(d->bus),
778                                      PCI_SLOT(s->dev.devfn),
779                                      intx,
780                                      0 /* isa_irq */);
781         if (rc < 0) {
782             XEN_PT_ERR(d, "unbinding of interrupt INT%c failed."
783                        " (machine irq: %i, rc: %d)"
784                        " But bravely continuing on..\n",
785                        'a' + intx, machine_irq, rc);
786         }
787     }
788 
789     if (s->msi) {
790         xen_pt_msi_disable(s);
791     }
792     if (s->msix) {
793         xen_pt_msix_disable(s);
794     }
795 
796     if (machine_irq) {
797         xen_pt_mapped_machine_irq[machine_irq]--;
798 
799         if (xen_pt_mapped_machine_irq[machine_irq] == 0) {
800             rc = xc_physdev_unmap_pirq(xen_xc, xen_domid, machine_irq);
801 
802             if (rc < 0) {
803                 XEN_PT_ERR(d, "unmapping of interrupt %i failed. (rc: %d)"
804                            " But bravely continuing on..\n",
805                            machine_irq, rc);
806             }
807         }
808     }
809 
810     /* delete all emulated config registers */
811     xen_pt_config_delete(s);
812 
813     xen_pt_unregister_regions(s);
814     memory_listener_unregister(&s->memory_listener);
815     memory_listener_unregister(&s->io_listener);
816 
817     xen_host_pci_device_put(&s->real_device);
818 }
819 
820 static Property xen_pci_passthrough_properties[] = {
821     DEFINE_PROP_PCI_HOST_DEVADDR("hostaddr", XenPCIPassthroughState, hostaddr),
822     DEFINE_PROP_END_OF_LIST(),
823 };
824 
825 static void xen_pci_passthrough_class_init(ObjectClass *klass, void *data)
826 {
827     DeviceClass *dc = DEVICE_CLASS(klass);
828     PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);
829 
830     k->init = xen_pt_initfn;
831     k->exit = xen_pt_unregister_device;
832     k->config_read = xen_pt_pci_read_config;
833     k->config_write = xen_pt_pci_write_config;
834     set_bit(DEVICE_CATEGORY_MISC, dc->categories);
835     dc->desc = "Assign an host PCI device with Xen";
836     dc->props = xen_pci_passthrough_properties;
837 };
838 
839 static const TypeInfo xen_pci_passthrough_info = {
840     .name = "xen-pci-passthrough",
841     .parent = TYPE_PCI_DEVICE,
842     .instance_size = sizeof(XenPCIPassthroughState),
843     .class_init = xen_pci_passthrough_class_init,
844 };
845 
846 static void xen_pci_passthrough_register_types(void)
847 {
848     type_register_static(&xen_pci_passthrough_info);
849 }
850 
851 type_init(xen_pci_passthrough_register_types)
852