xref: /openbmc/qemu/hw/intc/spapr_xive_kvm.c (revision 0ce46ab5)
1 /*
2  * QEMU PowerPC sPAPR XIVE interrupt controller model
3  *
4  * Copyright (c) 2017-2019, IBM Corporation.
5  *
6  * This code is licensed under the GPL version 2 or later. See the
7  * COPYING file in the top-level directory.
8  */
9 
10 #include "qemu/osdep.h"
11 #include "qemu/log.h"
12 #include "qemu/error-report.h"
13 #include "qapi/error.h"
14 #include "target/ppc/cpu.h"
15 #include "sysemu/cpus.h"
16 #include "sysemu/kvm.h"
17 #include "sysemu/runstate.h"
18 #include "hw/ppc/spapr.h"
19 #include "hw/ppc/spapr_cpu_core.h"
20 #include "hw/ppc/spapr_xive.h"
21 #include "hw/ppc/xive.h"
22 #include "kvm_ppc.h"
23 
24 #include <sys/ioctl.h>
25 
26 /*
27  * Helpers for CPU hotplug
28  *
29  * TODO: make a common KVMEnabledCPU layer for XICS and XIVE
30  */
31 typedef struct KVMEnabledCPU {
32     unsigned long vcpu_id;
33     QLIST_ENTRY(KVMEnabledCPU) node;
34 } KVMEnabledCPU;
35 
36 static QLIST_HEAD(, KVMEnabledCPU)
37     kvm_enabled_cpus = QLIST_HEAD_INITIALIZER(&kvm_enabled_cpus);
38 
39 static bool kvm_cpu_is_enabled(CPUState *cs)
40 {
41     KVMEnabledCPU *enabled_cpu;
42     unsigned long vcpu_id = kvm_arch_vcpu_id(cs);
43 
44     QLIST_FOREACH(enabled_cpu, &kvm_enabled_cpus, node) {
45         if (enabled_cpu->vcpu_id == vcpu_id) {
46             return true;
47         }
48     }
49     return false;
50 }
51 
52 static void kvm_cpu_enable(CPUState *cs)
53 {
54     KVMEnabledCPU *enabled_cpu;
55     unsigned long vcpu_id = kvm_arch_vcpu_id(cs);
56 
57     enabled_cpu = g_malloc(sizeof(*enabled_cpu));
58     enabled_cpu->vcpu_id = vcpu_id;
59     QLIST_INSERT_HEAD(&kvm_enabled_cpus, enabled_cpu, node);
60 }
61 
62 static void kvm_cpu_disable_all(void)
63 {
64     KVMEnabledCPU *enabled_cpu, *next;
65 
66     QLIST_FOREACH_SAFE(enabled_cpu, &kvm_enabled_cpus, node, next) {
67         QLIST_REMOVE(enabled_cpu, node);
68         g_free(enabled_cpu);
69     }
70 }
71 
72 /*
73  * XIVE Thread Interrupt Management context (KVM)
74  */
75 
76 void kvmppc_xive_cpu_set_state(XiveTCTX *tctx, Error **errp)
77 {
78     SpaprXive *xive = SPAPR_XIVE(tctx->xptr);
79     uint64_t state[2];
80     int ret;
81 
82     /* The KVM XIVE device is not in use yet */
83     if (xive->fd == -1) {
84         return;
85     }
86 
87     /* word0 and word1 of the OS ring. */
88     state[0] = *((uint64_t *) &tctx->regs[TM_QW1_OS]);
89 
90     ret = kvm_set_one_reg(tctx->cs, KVM_REG_PPC_VP_STATE, state);
91     if (ret != 0) {
92         error_setg_errno(errp, errno,
93                          "XIVE: could not restore KVM state of CPU %ld",
94                          kvm_arch_vcpu_id(tctx->cs));
95     }
96 }
97 
98 void kvmppc_xive_cpu_get_state(XiveTCTX *tctx, Error **errp)
99 {
100     SpaprXive *xive = SPAPR_XIVE(tctx->xptr);
101     uint64_t state[2] = { 0 };
102     int ret;
103 
104     /* The KVM XIVE device is not in use */
105     if (xive->fd == -1) {
106         return;
107     }
108 
109     ret = kvm_get_one_reg(tctx->cs, KVM_REG_PPC_VP_STATE, state);
110     if (ret != 0) {
111         error_setg_errno(errp, errno,
112                          "XIVE: could not capture KVM state of CPU %ld",
113                          kvm_arch_vcpu_id(tctx->cs));
114         return;
115     }
116 
117     /* word0 and word1 of the OS ring. */
118     *((uint64_t *) &tctx->regs[TM_QW1_OS]) = state[0];
119 }
120 
121 typedef struct {
122     XiveTCTX *tctx;
123     Error *err;
124 } XiveCpuGetState;
125 
126 static void kvmppc_xive_cpu_do_synchronize_state(CPUState *cpu,
127                                                  run_on_cpu_data arg)
128 {
129     XiveCpuGetState *s = arg.host_ptr;
130 
131     kvmppc_xive_cpu_get_state(s->tctx, &s->err);
132 }
133 
134 void kvmppc_xive_cpu_synchronize_state(XiveTCTX *tctx, Error **errp)
135 {
136     XiveCpuGetState s = {
137         .tctx = tctx,
138         .err = NULL,
139     };
140 
141     /*
142      * Kick the vCPU to make sure they are available for the KVM ioctl.
143      */
144     run_on_cpu(tctx->cs, kvmppc_xive_cpu_do_synchronize_state,
145                RUN_ON_CPU_HOST_PTR(&s));
146 
147     if (s.err) {
148         error_propagate(errp, s.err);
149         return;
150     }
151 }
152 
153 void kvmppc_xive_cpu_connect(XiveTCTX *tctx, Error **errp)
154 {
155     SpaprXive *xive = SPAPR_XIVE(tctx->xptr);
156     unsigned long vcpu_id;
157     int ret;
158 
159     /* The KVM XIVE device is not in use */
160     if (xive->fd == -1) {
161         return;
162     }
163 
164     /* Check if CPU was hot unplugged and replugged. */
165     if (kvm_cpu_is_enabled(tctx->cs)) {
166         return;
167     }
168 
169     vcpu_id = kvm_arch_vcpu_id(tctx->cs);
170 
171     ret = kvm_vcpu_enable_cap(tctx->cs, KVM_CAP_PPC_IRQ_XIVE, 0, xive->fd,
172                               vcpu_id, 0);
173     if (ret < 0) {
174         Error *local_err = NULL;
175 
176         error_setg(&local_err,
177                    "XIVE: unable to connect CPU%ld to KVM device: %s",
178                    vcpu_id, strerror(errno));
179         if (errno == ENOSPC) {
180             error_append_hint(&local_err, "Try -smp maxcpus=N with N < %u\n",
181                               MACHINE(qdev_get_machine())->smp.max_cpus);
182         }
183         error_propagate(errp, local_err);
184         return;
185     }
186 
187     kvm_cpu_enable(tctx->cs);
188 }
189 
190 /*
191  * XIVE Interrupt Source (KVM)
192  */
193 
194 void kvmppc_xive_set_source_config(SpaprXive *xive, uint32_t lisn, XiveEAS *eas,
195                                    Error **errp)
196 {
197     uint32_t end_idx;
198     uint32_t end_blk;
199     uint8_t priority;
200     uint32_t server;
201     bool masked;
202     uint32_t eisn;
203     uint64_t kvm_src;
204     Error *local_err = NULL;
205 
206     assert(xive_eas_is_valid(eas));
207 
208     end_idx = xive_get_field64(EAS_END_INDEX, eas->w);
209     end_blk = xive_get_field64(EAS_END_BLOCK, eas->w);
210     eisn = xive_get_field64(EAS_END_DATA, eas->w);
211     masked = xive_eas_is_masked(eas);
212 
213     spapr_xive_end_to_target(end_blk, end_idx, &server, &priority);
214 
215     kvm_src = priority << KVM_XIVE_SOURCE_PRIORITY_SHIFT &
216         KVM_XIVE_SOURCE_PRIORITY_MASK;
217     kvm_src |= server << KVM_XIVE_SOURCE_SERVER_SHIFT &
218         KVM_XIVE_SOURCE_SERVER_MASK;
219     kvm_src |= ((uint64_t) masked << KVM_XIVE_SOURCE_MASKED_SHIFT) &
220         KVM_XIVE_SOURCE_MASKED_MASK;
221     kvm_src |= ((uint64_t)eisn << KVM_XIVE_SOURCE_EISN_SHIFT) &
222         KVM_XIVE_SOURCE_EISN_MASK;
223 
224     kvm_device_access(xive->fd, KVM_DEV_XIVE_GRP_SOURCE_CONFIG, lisn,
225                       &kvm_src, true, &local_err);
226     if (local_err) {
227         error_propagate(errp, local_err);
228         return;
229     }
230 }
231 
232 void kvmppc_xive_sync_source(SpaprXive *xive, uint32_t lisn, Error **errp)
233 {
234     kvm_device_access(xive->fd, KVM_DEV_XIVE_GRP_SOURCE_SYNC, lisn,
235                       NULL, true, errp);
236 }
237 
238 /*
239  * At reset, the interrupt sources are simply created and MASKED. We
240  * only need to inform the KVM XIVE device about their type: LSI or
241  * MSI.
242  */
243 int kvmppc_xive_source_reset_one(XiveSource *xsrc, int srcno, Error **errp)
244 {
245     SpaprXive *xive = SPAPR_XIVE(xsrc->xive);
246     uint64_t state = 0;
247 
248     /* The KVM XIVE device is not in use */
249     if (xive->fd == -1) {
250         return -ENODEV;
251     }
252 
253     if (xive_source_irq_is_lsi(xsrc, srcno)) {
254         state |= KVM_XIVE_LEVEL_SENSITIVE;
255         if (xsrc->status[srcno] & XIVE_STATUS_ASSERTED) {
256             state |= KVM_XIVE_LEVEL_ASSERTED;
257         }
258     }
259 
260     return kvm_device_access(xive->fd, KVM_DEV_XIVE_GRP_SOURCE, srcno, &state,
261                              true, errp);
262 }
263 
264 static void kvmppc_xive_source_reset(XiveSource *xsrc, Error **errp)
265 {
266     SpaprXive *xive = SPAPR_XIVE(xsrc->xive);
267     int i;
268 
269     for (i = 0; i < xsrc->nr_irqs; i++) {
270         Error *local_err = NULL;
271 
272         if (!xive_eas_is_valid(&xive->eat[i])) {
273             continue;
274         }
275 
276         kvmppc_xive_source_reset_one(xsrc, i, &local_err);
277         if (local_err) {
278             error_propagate(errp, local_err);
279             return;
280         }
281     }
282 }
283 
284 /*
285  * This is used to perform the magic loads on the ESB pages, described
286  * in xive.h.
287  *
288  * Memory barriers should not be needed for loads (no store for now).
289  */
290 static uint64_t xive_esb_rw(XiveSource *xsrc, int srcno, uint32_t offset,
291                             uint64_t data, bool write)
292 {
293     uint64_t *addr = xsrc->esb_mmap + xive_source_esb_mgmt(xsrc, srcno) +
294         offset;
295 
296     if (write) {
297         *addr = cpu_to_be64(data);
298         return -1;
299     } else {
300         /* Prevent the compiler from optimizing away the load */
301         volatile uint64_t value = be64_to_cpu(*addr);
302         return value;
303     }
304 }
305 
306 static uint8_t xive_esb_read(XiveSource *xsrc, int srcno, uint32_t offset)
307 {
308     return xive_esb_rw(xsrc, srcno, offset, 0, 0) & 0x3;
309 }
310 
311 static void xive_esb_trigger(XiveSource *xsrc, int srcno)
312 {
313     uint64_t *addr = xsrc->esb_mmap + xive_source_esb_page(xsrc, srcno);
314 
315     *addr = 0x0;
316 }
317 
318 uint64_t kvmppc_xive_esb_rw(XiveSource *xsrc, int srcno, uint32_t offset,
319                             uint64_t data, bool write)
320 {
321     if (write) {
322         return xive_esb_rw(xsrc, srcno, offset, data, 1);
323     }
324 
325     /*
326      * Special Load EOI handling for LSI sources. Q bit is never set
327      * and the interrupt should be re-triggered if the level is still
328      * asserted.
329      */
330     if (xive_source_irq_is_lsi(xsrc, srcno) &&
331         offset == XIVE_ESB_LOAD_EOI) {
332         xive_esb_read(xsrc, srcno, XIVE_ESB_SET_PQ_00);
333         if (xsrc->status[srcno] & XIVE_STATUS_ASSERTED) {
334             xive_esb_trigger(xsrc, srcno);
335         }
336         return 0;
337     } else {
338         return xive_esb_rw(xsrc, srcno, offset, 0, 0);
339     }
340 }
341 
342 static void kvmppc_xive_source_get_state(XiveSource *xsrc)
343 {
344     SpaprXive *xive = SPAPR_XIVE(xsrc->xive);
345     int i;
346 
347     for (i = 0; i < xsrc->nr_irqs; i++) {
348         uint8_t pq;
349 
350         if (!xive_eas_is_valid(&xive->eat[i])) {
351             continue;
352         }
353 
354         /* Perform a load without side effect to retrieve the PQ bits */
355         pq = xive_esb_read(xsrc, i, XIVE_ESB_GET);
356 
357         /* and save PQ locally */
358         xive_source_esb_set(xsrc, i, pq);
359     }
360 }
361 
362 void kvmppc_xive_source_set_irq(void *opaque, int srcno, int val)
363 {
364     XiveSource *xsrc = opaque;
365 
366     if (!xive_source_irq_is_lsi(xsrc, srcno)) {
367         if (!val) {
368             return;
369         }
370     } else {
371         if (val) {
372             xsrc->status[srcno] |= XIVE_STATUS_ASSERTED;
373         } else {
374             xsrc->status[srcno] &= ~XIVE_STATUS_ASSERTED;
375         }
376     }
377 
378     xive_esb_trigger(xsrc, srcno);
379 }
380 
381 /*
382  * sPAPR XIVE interrupt controller (KVM)
383  */
384 void kvmppc_xive_get_queue_config(SpaprXive *xive, uint8_t end_blk,
385                                   uint32_t end_idx, XiveEND *end,
386                                   Error **errp)
387 {
388     struct kvm_ppc_xive_eq kvm_eq = { 0 };
389     uint64_t kvm_eq_idx;
390     uint8_t priority;
391     uint32_t server;
392     Error *local_err = NULL;
393 
394     assert(xive_end_is_valid(end));
395 
396     /* Encode the tuple (server, prio) as a KVM EQ index */
397     spapr_xive_end_to_target(end_blk, end_idx, &server, &priority);
398 
399     kvm_eq_idx = priority << KVM_XIVE_EQ_PRIORITY_SHIFT &
400             KVM_XIVE_EQ_PRIORITY_MASK;
401     kvm_eq_idx |= server << KVM_XIVE_EQ_SERVER_SHIFT &
402         KVM_XIVE_EQ_SERVER_MASK;
403 
404     kvm_device_access(xive->fd, KVM_DEV_XIVE_GRP_EQ_CONFIG, kvm_eq_idx,
405                       &kvm_eq, false, &local_err);
406     if (local_err) {
407         error_propagate(errp, local_err);
408         return;
409     }
410 
411     /*
412      * The EQ index and toggle bit are updated by HW. These are the
413      * only fields from KVM we want to update QEMU with. The other END
414      * fields should already be in the QEMU END table.
415      */
416     end->w1 = xive_set_field32(END_W1_GENERATION, 0ul, kvm_eq.qtoggle) |
417         xive_set_field32(END_W1_PAGE_OFF, 0ul, kvm_eq.qindex);
418 }
419 
420 void kvmppc_xive_set_queue_config(SpaprXive *xive, uint8_t end_blk,
421                                   uint32_t end_idx, XiveEND *end,
422                                   Error **errp)
423 {
424     struct kvm_ppc_xive_eq kvm_eq = { 0 };
425     uint64_t kvm_eq_idx;
426     uint8_t priority;
427     uint32_t server;
428     Error *local_err = NULL;
429 
430     /*
431      * Build the KVM state from the local END structure.
432      */
433 
434     kvm_eq.flags = 0;
435     if (xive_get_field32(END_W0_UCOND_NOTIFY, end->w0)) {
436         kvm_eq.flags |= KVM_XIVE_EQ_ALWAYS_NOTIFY;
437     }
438 
439     /*
440      * If the hcall is disabling the EQ, set the size and page address
441      * to zero. When migrating, only valid ENDs are taken into
442      * account.
443      */
444     if (xive_end_is_valid(end)) {
445         kvm_eq.qshift = xive_get_field32(END_W0_QSIZE, end->w0) + 12;
446         kvm_eq.qaddr  = xive_end_qaddr(end);
447         /*
448          * The EQ toggle bit and index should only be relevant when
449          * restoring the EQ state
450          */
451         kvm_eq.qtoggle = xive_get_field32(END_W1_GENERATION, end->w1);
452         kvm_eq.qindex  = xive_get_field32(END_W1_PAGE_OFF, end->w1);
453     } else {
454         kvm_eq.qshift = 0;
455         kvm_eq.qaddr  = 0;
456     }
457 
458     /* Encode the tuple (server, prio) as a KVM EQ index */
459     spapr_xive_end_to_target(end_blk, end_idx, &server, &priority);
460 
461     kvm_eq_idx = priority << KVM_XIVE_EQ_PRIORITY_SHIFT &
462             KVM_XIVE_EQ_PRIORITY_MASK;
463     kvm_eq_idx |= server << KVM_XIVE_EQ_SERVER_SHIFT &
464         KVM_XIVE_EQ_SERVER_MASK;
465 
466     kvm_device_access(xive->fd, KVM_DEV_XIVE_GRP_EQ_CONFIG, kvm_eq_idx,
467                       &kvm_eq, true, &local_err);
468     if (local_err) {
469         error_propagate(errp, local_err);
470         return;
471     }
472 }
473 
474 void kvmppc_xive_reset(SpaprXive *xive, Error **errp)
475 {
476     kvm_device_access(xive->fd, KVM_DEV_XIVE_GRP_CTRL, KVM_DEV_XIVE_RESET,
477                       NULL, true, errp);
478 }
479 
480 static void kvmppc_xive_get_queues(SpaprXive *xive, Error **errp)
481 {
482     Error *local_err = NULL;
483     int i;
484 
485     for (i = 0; i < xive->nr_ends; i++) {
486         if (!xive_end_is_valid(&xive->endt[i])) {
487             continue;
488         }
489 
490         kvmppc_xive_get_queue_config(xive, SPAPR_XIVE_BLOCK_ID, i,
491                                      &xive->endt[i], &local_err);
492         if (local_err) {
493             error_propagate(errp, local_err);
494             return;
495         }
496     }
497 }
498 
499 /*
500  * The primary goal of the XIVE VM change handler is to mark the EQ
501  * pages dirty when all XIVE event notifications have stopped.
502  *
503  * Whenever the VM is stopped, the VM change handler sets the source
504  * PQs to PENDING to stop the flow of events and to possibly catch a
505  * triggered interrupt occuring while the VM is stopped. The previous
506  * state is saved in anticipation of a migration. The XIVE controller
507  * is then synced through KVM to flush any in-flight event
508  * notification and stabilize the EQs.
509  *
510  * At this stage, we can mark the EQ page dirty and let a migration
511  * sequence transfer the EQ pages to the destination, which is done
512  * just after the stop state.
513  *
514  * The previous configuration of the sources is restored when the VM
515  * runs again. If an interrupt was queued while the VM was stopped,
516  * simply generate a trigger.
517  */
518 static void kvmppc_xive_change_state_handler(void *opaque, int running,
519                                              RunState state)
520 {
521     SpaprXive *xive = opaque;
522     XiveSource *xsrc = &xive->source;
523     Error *local_err = NULL;
524     int i;
525 
526     /*
527      * Restore the sources to their initial state. This is called when
528      * the VM resumes after a stop or a migration.
529      */
530     if (running) {
531         for (i = 0; i < xsrc->nr_irqs; i++) {
532             uint8_t pq;
533             uint8_t old_pq;
534 
535             if (!xive_eas_is_valid(&xive->eat[i])) {
536                 continue;
537             }
538 
539             pq = xive_source_esb_get(xsrc, i);
540             old_pq = xive_esb_read(xsrc, i, XIVE_ESB_SET_PQ_00 + (pq << 8));
541 
542             /*
543              * An interrupt was queued while the VM was stopped,
544              * generate a trigger.
545              */
546             if (pq == XIVE_ESB_RESET && old_pq == XIVE_ESB_QUEUED) {
547                 xive_esb_trigger(xsrc, i);
548             }
549         }
550 
551         return;
552     }
553 
554     /*
555      * Mask the sources, to stop the flow of event notifications, and
556      * save the PQs locally in the XiveSource object. The XiveSource
557      * state will be collected later on by its vmstate handler if a
558      * migration is in progress.
559      */
560     for (i = 0; i < xsrc->nr_irqs; i++) {
561         uint8_t pq;
562 
563         if (!xive_eas_is_valid(&xive->eat[i])) {
564             continue;
565         }
566 
567         pq = xive_esb_read(xsrc, i, XIVE_ESB_GET);
568 
569         /*
570          * PQ is set to PENDING to possibly catch a triggered
571          * interrupt occuring while the VM is stopped (hotplug event
572          * for instance) .
573          */
574         if (pq != XIVE_ESB_OFF) {
575             pq = xive_esb_read(xsrc, i, XIVE_ESB_SET_PQ_10);
576         }
577         xive_source_esb_set(xsrc, i, pq);
578     }
579 
580     /*
581      * Sync the XIVE controller in KVM, to flush in-flight event
582      * notification that should be enqueued in the EQs and mark the
583      * XIVE EQ pages dirty to collect all updates.
584      */
585     kvm_device_access(xive->fd, KVM_DEV_XIVE_GRP_CTRL,
586                       KVM_DEV_XIVE_EQ_SYNC, NULL, true, &local_err);
587     if (local_err) {
588         error_report_err(local_err);
589         return;
590     }
591 }
592 
593 void kvmppc_xive_synchronize_state(SpaprXive *xive, Error **errp)
594 {
595     /* The KVM XIVE device is not in use */
596     if (xive->fd == -1) {
597         return;
598     }
599 
600     /*
601      * When the VM is stopped, the sources are masked and the previous
602      * state is saved in anticipation of a migration. We should not
603      * synchronize the source state in that case else we will override
604      * the saved state.
605      */
606     if (runstate_is_running()) {
607         kvmppc_xive_source_get_state(&xive->source);
608     }
609 
610     /* EAT: there is no extra state to query from KVM */
611 
612     /* ENDT */
613     kvmppc_xive_get_queues(xive, errp);
614 }
615 
616 /*
617  * The SpaprXive 'pre_save' method is called by the vmstate handler of
618  * the SpaprXive model, after the XIVE controller is synced in the VM
619  * change handler.
620  */
621 int kvmppc_xive_pre_save(SpaprXive *xive)
622 {
623     Error *local_err = NULL;
624 
625     /* The KVM XIVE device is not in use */
626     if (xive->fd == -1) {
627         return 0;
628     }
629 
630     /* EAT: there is no extra state to query from KVM */
631 
632     /* ENDT */
633     kvmppc_xive_get_queues(xive, &local_err);
634     if (local_err) {
635         error_report_err(local_err);
636         return -1;
637     }
638 
639     return 0;
640 }
641 
642 /*
643  * The SpaprXive 'post_load' method is not called by a vmstate
644  * handler. It is called at the sPAPR machine level at the end of the
645  * migration sequence by the sPAPR IRQ backend 'post_load' method,
646  * when all XIVE states have been transferred and loaded.
647  */
648 int kvmppc_xive_post_load(SpaprXive *xive, int version_id)
649 {
650     Error *local_err = NULL;
651     CPUState *cs;
652     int i;
653 
654     /* The KVM XIVE device should be in use */
655     assert(xive->fd != -1);
656 
657     /* Restore the ENDT first. The targetting depends on it. */
658     for (i = 0; i < xive->nr_ends; i++) {
659         if (!xive_end_is_valid(&xive->endt[i])) {
660             continue;
661         }
662 
663         kvmppc_xive_set_queue_config(xive, SPAPR_XIVE_BLOCK_ID, i,
664                                      &xive->endt[i], &local_err);
665         if (local_err) {
666             error_report_err(local_err);
667             return -1;
668         }
669     }
670 
671     /* Restore the EAT */
672     for (i = 0; i < xive->nr_irqs; i++) {
673         if (!xive_eas_is_valid(&xive->eat[i])) {
674             continue;
675         }
676 
677         /*
678          * We can only restore the source config if the source has been
679          * previously set in KVM. Since we don't do that for all interrupts
680          * at reset time anymore, let's do it now.
681          */
682         kvmppc_xive_source_reset_one(&xive->source, i, &local_err);
683         if (local_err) {
684             error_report_err(local_err);
685             return -1;
686         }
687 
688         kvmppc_xive_set_source_config(xive, i, &xive->eat[i], &local_err);
689         if (local_err) {
690             error_report_err(local_err);
691             return -1;
692         }
693     }
694 
695     /*
696      * Restore the thread interrupt contexts of initial CPUs.
697      *
698      * The context of hotplugged CPUs is restored later, by the
699      * 'post_load' handler of the XiveTCTX model because they are not
700      * available at the time the SpaprXive 'post_load' method is
701      * called. We can not restore the context of all CPUs in the
702      * 'post_load' handler of XiveTCTX because the machine is not
703      * necessarily connected to the KVM device at that time.
704      */
705     CPU_FOREACH(cs) {
706         PowerPCCPU *cpu = POWERPC_CPU(cs);
707 
708         kvmppc_xive_cpu_set_state(spapr_cpu_state(cpu)->tctx, &local_err);
709         if (local_err) {
710             error_report_err(local_err);
711             return -1;
712         }
713     }
714 
715     /* The source states will be restored when the machine starts running */
716     return 0;
717 }
718 
719 static void *kvmppc_xive_mmap(SpaprXive *xive, int pgoff, size_t len,
720                               Error **errp)
721 {
722     void *addr;
723     uint32_t page_shift = 16; /* TODO: fix page_shift */
724 
725     addr = mmap(NULL, len, PROT_WRITE | PROT_READ, MAP_SHARED, xive->fd,
726                 pgoff << page_shift);
727     if (addr == MAP_FAILED) {
728         error_setg_errno(errp, errno, "XIVE: unable to set memory mapping");
729         return NULL;
730     }
731 
732     return addr;
733 }
734 
735 /*
736  * All the XIVE memory regions are now backed by mappings from the KVM
737  * XIVE device.
738  */
739 int kvmppc_xive_connect(SpaprInterruptController *intc, uint32_t nr_servers,
740                         Error **errp)
741 {
742     SpaprXive *xive = SPAPR_XIVE(intc);
743     XiveSource *xsrc = &xive->source;
744     Error *local_err = NULL;
745     size_t esb_len = (1ull << xsrc->esb_shift) * xsrc->nr_irqs;
746     size_t tima_len = 4ull << TM_SHIFT;
747     CPUState *cs;
748 
749     /*
750      * The KVM XIVE device already in use. This is the case when
751      * rebooting under the XIVE-only interrupt mode.
752      */
753     if (xive->fd != -1) {
754         return 0;
755     }
756 
757     if (!kvmppc_has_cap_xive()) {
758         error_setg(errp, "IRQ_XIVE capability must be present for KVM");
759         return -1;
760     }
761 
762     /* First, create the KVM XIVE device */
763     xive->fd = kvm_create_device(kvm_state, KVM_DEV_TYPE_XIVE, false);
764     if (xive->fd < 0) {
765         error_setg_errno(errp, -xive->fd, "XIVE: error creating KVM device");
766         return -1;
767     }
768 
769     /* Tell KVM about the # of VCPUs we may have */
770     if (kvm_device_check_attr(xive->fd, KVM_DEV_XIVE_GRP_CTRL,
771                               KVM_DEV_XIVE_NR_SERVERS)) {
772         if (kvm_device_access(xive->fd, KVM_DEV_XIVE_GRP_CTRL,
773                               KVM_DEV_XIVE_NR_SERVERS, &nr_servers, true,
774                               &local_err)) {
775             goto fail;
776         }
777     }
778 
779     /*
780      * 1. Source ESB pages - KVM mapping
781      */
782     xsrc->esb_mmap = kvmppc_xive_mmap(xive, KVM_XIVE_ESB_PAGE_OFFSET, esb_len,
783                                       &local_err);
784     if (local_err) {
785         goto fail;
786     }
787 
788     memory_region_init_ram_device_ptr(&xsrc->esb_mmio_kvm, OBJECT(xsrc),
789                                       "xive.esb", esb_len, xsrc->esb_mmap);
790     memory_region_add_subregion_overlap(&xsrc->esb_mmio, 0,
791                                         &xsrc->esb_mmio_kvm, 1);
792 
793     /*
794      * 2. END ESB pages (No KVM support yet)
795      */
796 
797     /*
798      * 3. TIMA pages - KVM mapping
799      */
800     xive->tm_mmap = kvmppc_xive_mmap(xive, KVM_XIVE_TIMA_PAGE_OFFSET, tima_len,
801                                      &local_err);
802     if (local_err) {
803         goto fail;
804     }
805     memory_region_init_ram_device_ptr(&xive->tm_mmio_kvm, OBJECT(xive),
806                                       "xive.tima", tima_len, xive->tm_mmap);
807     memory_region_add_subregion_overlap(&xive->tm_mmio, 0,
808                                         &xive->tm_mmio_kvm, 1);
809 
810     xive->change = qemu_add_vm_change_state_handler(
811         kvmppc_xive_change_state_handler, xive);
812 
813     /* Connect the presenters to the initial VCPUs of the machine */
814     CPU_FOREACH(cs) {
815         PowerPCCPU *cpu = POWERPC_CPU(cs);
816 
817         kvmppc_xive_cpu_connect(spapr_cpu_state(cpu)->tctx, &local_err);
818         if (local_err) {
819             goto fail;
820         }
821     }
822 
823     /* Update the KVM sources */
824     kvmppc_xive_source_reset(xsrc, &local_err);
825     if (local_err) {
826         goto fail;
827     }
828 
829     kvm_kernel_irqchip = true;
830     kvm_msi_via_irqfd_allowed = true;
831     kvm_gsi_direct_mapping = true;
832     return 0;
833 
834 fail:
835     error_propagate(errp, local_err);
836     kvmppc_xive_disconnect(intc);
837     return -1;
838 }
839 
840 void kvmppc_xive_disconnect(SpaprInterruptController *intc)
841 {
842     SpaprXive *xive = SPAPR_XIVE(intc);
843     XiveSource *xsrc;
844     size_t esb_len;
845 
846     /* The KVM XIVE device is not in use */
847     if (!xive || xive->fd == -1) {
848         return;
849     }
850 
851     /* Clear the KVM mapping */
852     xsrc = &xive->source;
853     esb_len = (1ull << xsrc->esb_shift) * xsrc->nr_irqs;
854 
855     if (xsrc->esb_mmap) {
856         memory_region_del_subregion(&xsrc->esb_mmio, &xsrc->esb_mmio_kvm);
857         object_unparent(OBJECT(&xsrc->esb_mmio_kvm));
858         munmap(xsrc->esb_mmap, esb_len);
859         xsrc->esb_mmap = NULL;
860     }
861 
862     if (xive->tm_mmap) {
863         memory_region_del_subregion(&xive->tm_mmio, &xive->tm_mmio_kvm);
864         object_unparent(OBJECT(&xive->tm_mmio_kvm));
865         munmap(xive->tm_mmap, 4ull << TM_SHIFT);
866         xive->tm_mmap = NULL;
867     }
868 
869     /*
870      * When the KVM device fd is closed, the KVM device is destroyed
871      * and removed from the list of devices of the VM. The VCPU
872      * presenters are also detached from the device.
873      */
874     if (xive->fd != -1) {
875         close(xive->fd);
876         xive->fd = -1;
877     }
878 
879     kvm_kernel_irqchip = false;
880     kvm_msi_via_irqfd_allowed = false;
881     kvm_gsi_direct_mapping = false;
882 
883     /* Clear the local list of presenter (hotplug) */
884     kvm_cpu_disable_all();
885 
886     /* VM Change state handler is not needed anymore */
887     if (xive->change) {
888         qemu_del_vm_change_state_handler(xive->change);
889         xive->change = NULL;
890     }
891 }
892