master
c 509 lines 14.1 KB
Raw
1 /*
2 * QEMU PowerPC pSeries Logical Partition (aka sPAPR) hardware System Emulator
3 *
4 * PAPR Virtualized Interrupt System, aka ICS/ICP aka xics, in-kernel emulation
5 *
6 * Copyright (c) 2013 David Gibson, IBM Corporation.
7 *
8 * Permission is hereby granted, free of charge, to any person obtaining a copy
9 * of this software and associated documentation files (the "Software"), to deal
10 * in the Software without restriction, including without limitation the rights
11 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
12 * copies of the Software, and to permit persons to whom the Software is
13 * furnished to do so, subject to the following conditions:
14 *
15 * The above copyright notice and this permission notice shall be included in
16 * all copies or substantial portions of the Software.
17 *
18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
19 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
20 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
21 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
22 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
23 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
24 * THE SOFTWARE.
25 *
26 */
27
28 #include "qemu/osdep.h"
29 #include "qapi/error.h"
30 #include "trace.h"
31 #include "system/kvm.h"
32 #include "hw/ppc/spapr.h"
33 #include "hw/ppc/spapr_cpu_core.h"
34 #include "hw/ppc/xics.h"
35 #include "hw/ppc/xics_spapr.h"
36 #include "kvm_ppc.h"
37 #include "qemu/config-file.h"
38 #include "qemu/error-report.h"
39
40 #include <sys/ioctl.h>
41
42 static int kernel_xics_fd = -1;
43
44 typedef struct KVMEnabledICP {
45 unsigned long vcpu_id;
46 QLIST_ENTRY(KVMEnabledICP) node;
47 } KVMEnabledICP;
48
49 static QLIST_HEAD(, KVMEnabledICP)
50 kvm_enabled_icps = QLIST_HEAD_INITIALIZER(&kvm_enabled_icps);
51
52 static void kvm_disable_icps(void)
53 {
54 KVMEnabledICP *enabled_icp, *next;
55
56 QLIST_FOREACH_SAFE(enabled_icp, &kvm_enabled_icps, node, next) {
57 QLIST_REMOVE(enabled_icp, node);
58 g_free(enabled_icp);
59 }
60 }
61
62 /*
63 * ICP-KVM
64 */
65 void icp_get_kvm_state(ICPState *icp)
66 {
67 uint64_t state;
68 int ret;
69
70 /* The KVM XICS device is not in use */
71 if (kernel_xics_fd == -1) {
72 return;
73 }
74
75 /* ICP for this CPU thread is not in use, exiting */
76 if (!icp->cs) {
77 return;
78 }
79
80 ret = kvm_get_one_reg(icp->cs, KVM_REG_PPC_ICP_STATE, &state);
81 if (ret != 0) {
82 error_report("Unable to retrieve KVM interrupt controller state"
83 " for CPU %ld: %s", kvm_arch_vcpu_id(icp->cs), strerror(errno));
84 exit(1);
85 }
86
87 icp->xirr = state >> KVM_REG_PPC_ICP_XISR_SHIFT;
88 icp->mfrr = (state >> KVM_REG_PPC_ICP_MFRR_SHIFT)
89 & KVM_REG_PPC_ICP_MFRR_MASK;
90 icp->pending_priority = (state >> KVM_REG_PPC_ICP_PPRI_SHIFT)
91 & KVM_REG_PPC_ICP_PPRI_MASK;
92 }
93
94 static void do_icp_synchronize_state(CPUState *cpu, run_on_cpu_data arg)
95 {
96 icp_get_kvm_state(arg.host_ptr);
97 }
98
99 void icp_synchronize_state(ICPState *icp)
100 {
101 if (icp->cs) {
102 run_on_cpu(icp->cs, do_icp_synchronize_state, RUN_ON_CPU_HOST_PTR(icp));
103 }
104 }
105
106 int icp_set_kvm_state(ICPState *icp, Error **errp)
107 {
108 uint64_t state;
109 int ret;
110
111 /* The KVM XICS device is not in use */
112 if (kernel_xics_fd == -1) {
113 return 0;
114 }
115
116 /* ICP for this CPU thread is not in use, exiting */
117 if (!icp->cs) {
118 return 0;
119 }
120
121 state = ((uint64_t)icp->xirr << KVM_REG_PPC_ICP_XISR_SHIFT)
122 | ((uint64_t)icp->mfrr << KVM_REG_PPC_ICP_MFRR_SHIFT)
123 | ((uint64_t)icp->pending_priority << KVM_REG_PPC_ICP_PPRI_SHIFT);
124
125 ret = kvm_set_one_reg(icp->cs, KVM_REG_PPC_ICP_STATE, &state);
126 if (ret < 0) {
127 error_setg_errno(errp, -ret,
128 "Unable to restore KVM interrupt controller state (0x%"
129 PRIx64 ") for CPU %ld", state,
130 kvm_arch_vcpu_id(icp->cs));
131 return ret;
132 }
133
134 return 0;
135 }
136
137 void icp_kvm_realize(DeviceState *dev, Error **errp)
138 {
139 ICPState *icp = ICP(dev);
140 CPUState *cs;
141 KVMEnabledICP *enabled_icp;
142 unsigned long vcpu_id;
143 int ret;
144
145 /* The KVM XICS device is not in use */
146 if (kernel_xics_fd == -1) {
147 return;
148 }
149
150 cs = icp->cs;
151 vcpu_id = kvm_arch_vcpu_id(cs);
152
153 /*
154 * If we are reusing a parked vCPU fd corresponding to the CPU
155 * which was hot-removed earlier we don't have to renable
156 * KVM_CAP_IRQ_XICS capability again.
157 */
158 QLIST_FOREACH(enabled_icp, &kvm_enabled_icps, node) {
159 if (enabled_icp->vcpu_id == vcpu_id) {
160 return;
161 }
162 }
163
164 ret = kvm_vcpu_enable_cap(cs, KVM_CAP_IRQ_XICS, 0, kernel_xics_fd, vcpu_id);
165 if (ret < 0) {
166 Error *local_err = NULL;
167
168 error_setg_errno(&local_err, errno,
169 "Unable to connect CPU%ld to kernel XICS",
170 vcpu_id);
171 if (errno == ENOSPC) {
172 error_append_hint(&local_err, "Try -smp maxcpus=N with N < %u\n",
173 MACHINE(qdev_get_machine())->smp.max_cpus);
174 }
175 error_propagate(errp, local_err);
176 return;
177 }
178 enabled_icp = g_malloc(sizeof(*enabled_icp));
179 enabled_icp->vcpu_id = vcpu_id;
180 QLIST_INSERT_HEAD(&kvm_enabled_icps, enabled_icp, node);
181 }
182
183 /*
184 * ICS-KVM
185 */
186 void ics_get_kvm_state(ICSState *ics)
187 {
188 uint64_t state;
189 int i;
190
191 /* The KVM XICS device is not in use */
192 if (kernel_xics_fd == -1) {
193 return;
194 }
195
196 for (i = 0; i < ics->nr_irqs; i++) {
197 ICSIRQState *irq = &ics->irqs[i];
198
199 if (ics_irq_free(ics, i)) {
200 continue;
201 }
202
203 kvm_device_access(kernel_xics_fd, KVM_DEV_XICS_GRP_SOURCES,
204 i + ics->offset, &state, false, &error_fatal);
205
206 irq->server = state & KVM_XICS_DESTINATION_MASK;
207 irq->saved_priority = (state >> KVM_XICS_PRIORITY_SHIFT)
208 & KVM_XICS_PRIORITY_MASK;
209 /*
210 * To be consistent with the software emulation in xics.c, we
211 * split out the masked state + priority that we get from the
212 * kernel into 'current priority' (0xff if masked) and
213 * 'saved priority' (if masked, this is the priority the
214 * interrupt had before it was masked). Masking and unmasking
215 * are done with the ibm,int-off and ibm,int-on RTAS calls.
216 */
217 if (state & KVM_XICS_MASKED) {
218 irq->priority = 0xff;
219 } else {
220 irq->priority = irq->saved_priority;
221 }
222
223 irq->status = 0;
224 if (state & KVM_XICS_PENDING) {
225 if (state & KVM_XICS_LEVEL_SENSITIVE) {
226 irq->status |= XICS_STATUS_ASSERTED;
227 } else {
228 /*
229 * A pending edge-triggered interrupt (or MSI)
230 * must have been rejected previously when we
231 * first detected it and tried to deliver it,
232 * so mark it as pending and previously rejected
233 * for consistency with how xics.c works.
234 */
235 irq->status |= XICS_STATUS_MASKED_PENDING
236 | XICS_STATUS_REJECTED;
237 }
238 }
239 if (state & KVM_XICS_PRESENTED) {
240 irq->status |= XICS_STATUS_PRESENTED;
241 }
242 if (state & KVM_XICS_QUEUED) {
243 irq->status |= XICS_STATUS_QUEUED;
244 }
245 }
246 }
247
248 void ics_synchronize_state(ICSState *ics)
249 {
250 ics_get_kvm_state(ics);
251 }
252
253 int ics_set_kvm_state_one(ICSState *ics, int srcno, Error **errp)
254 {
255 uint64_t state;
256 ICSIRQState *irq = &ics->irqs[srcno];
257 int ret;
258
259 /* The KVM XICS device is not in use */
260 if (kernel_xics_fd == -1) {
261 return 0;
262 }
263
264 state = irq->server;
265 state |= (uint64_t)(irq->saved_priority & KVM_XICS_PRIORITY_MASK)
266 << KVM_XICS_PRIORITY_SHIFT;
267 if (irq->priority != irq->saved_priority) {
268 assert(irq->priority == 0xff);
269 }
270
271 if (irq->priority == 0xff) {
272 state |= KVM_XICS_MASKED;
273 }
274
275 if (irq->flags & XICS_FLAGS_IRQ_LSI) {
276 state |= KVM_XICS_LEVEL_SENSITIVE;
277 if (irq->status & XICS_STATUS_ASSERTED) {
278 state |= KVM_XICS_PENDING;
279 }
280 } else {
281 if (irq->status & XICS_STATUS_MASKED_PENDING) {
282 state |= KVM_XICS_PENDING;
283 }
284 }
285 if (irq->status & XICS_STATUS_PRESENTED) {
286 state |= KVM_XICS_PRESENTED;
287 }
288 if (irq->status & XICS_STATUS_QUEUED) {
289 state |= KVM_XICS_QUEUED;
290 }
291
292 ret = kvm_device_access(kernel_xics_fd, KVM_DEV_XICS_GRP_SOURCES,
293 srcno + ics->offset, &state, true, errp);
294 if (ret < 0) {
295 return ret;
296 }
297
298 return 0;
299 }
300
301 int ics_set_kvm_state(ICSState *ics, Error **errp)
302 {
303 int i;
304
305 /* The KVM XICS device is not in use */
306 if (kernel_xics_fd == -1) {
307 return 0;
308 }
309
310 for (i = 0; i < ics->nr_irqs; i++) {
311 int ret;
312
313 if (ics_irq_free(ics, i)) {
314 continue;
315 }
316
317 ret = ics_set_kvm_state_one(ics, i, errp);
318 if (ret < 0) {
319 return ret;
320 }
321 }
322
323 return 0;
324 }
325
326 void ics_kvm_set_irq(ICSState *ics, int srcno, int val)
327 {
328 struct kvm_irq_level args;
329 int rc;
330
331 /* The KVM XICS device should be in use */
332 assert(kernel_xics_fd != -1);
333
334 args.irq = srcno + ics->offset;
335 if (ics->irqs[srcno].flags & XICS_FLAGS_IRQ_MSI) {
336 if (!val) {
337 return;
338 }
339 args.level = KVM_INTERRUPT_SET;
340 } else {
341 args.level = val ? KVM_INTERRUPT_SET_LEVEL : KVM_INTERRUPT_UNSET;
342 }
343 rc = kvm_vm_ioctl(kvm_state, KVM_IRQ_LINE, &args);
344 if (rc < 0) {
345 perror("kvm_irq_line");
346 }
347 }
348
349 int xics_kvm_connect(SpaprInterruptController *intc, uint32_t nr_servers,
350 Error **errp)
351 {
352 ICSState *ics = ICS_SPAPR(intc);
353 int rc;
354 CPUState *cs;
355 Error *local_err = NULL;
356
357 /*
358 * The KVM XICS device already in use. This is the case when
359 * rebooting under the XICS-only interrupt mode.
360 */
361 if (kernel_xics_fd != -1) {
362 return 0;
363 }
364
365 if (!kvm_enabled() || !kvm_check_extension(kvm_state, KVM_CAP_IRQ_XICS)) {
366 error_setg(errp,
367 "KVM and IRQ_XICS capability must be present for in-kernel XICS");
368 return -1;
369 }
370
371 rc = kvmppc_define_rtas_kernel_token(RTAS_IBM_SET_XIVE, "ibm,set-xive");
372 if (rc < 0) {
373 error_setg_errno(&local_err, -rc,
374 "kvmppc_define_rtas_kernel_token: ibm,set-xive");
375 goto fail;
376 }
377
378 rc = kvmppc_define_rtas_kernel_token(RTAS_IBM_GET_XIVE, "ibm,get-xive");
379 if (rc < 0) {
380 error_setg_errno(&local_err, -rc,
381 "kvmppc_define_rtas_kernel_token: ibm,get-xive");
382 goto fail;
383 }
384
385 rc = kvmppc_define_rtas_kernel_token(RTAS_IBM_INT_ON, "ibm,int-on");
386 if (rc < 0) {
387 error_setg_errno(&local_err, -rc,
388 "kvmppc_define_rtas_kernel_token: ibm,int-on");
389 goto fail;
390 }
391
392 rc = kvmppc_define_rtas_kernel_token(RTAS_IBM_INT_OFF, "ibm,int-off");
393 if (rc < 0) {
394 error_setg_errno(&local_err, -rc,
395 "kvmppc_define_rtas_kernel_token: ibm,int-off");
396 goto fail;
397 }
398
399 /* Create the KVM XICS device */
400 rc = kvm_create_device(kvm_state, KVM_DEV_TYPE_XICS, false);
401 if (rc < 0) {
402 error_setg_errno(&local_err, -rc, "Error on KVM_CREATE_DEVICE for XICS");
403 goto fail;
404 }
405
406 /* Tell KVM about the # of VCPUs we may have (POWER9 and newer only) */
407 if (kvm_device_check_attr(rc, KVM_DEV_XICS_GRP_CTRL,
408 KVM_DEV_XICS_NR_SERVERS)) {
409 if (kvm_device_access(rc, KVM_DEV_XICS_GRP_CTRL,
410 KVM_DEV_XICS_NR_SERVERS, &nr_servers, true,
411 &local_err)) {
412 goto fail;
413 }
414 }
415
416 kernel_xics_fd = rc;
417 kvm_kernel_irqchip = true;
418 kvm_msi_via_irqfd_allowed = true;
419 kvm_gsi_direct_mapping = true;
420
421 /* Create the presenters */
422 CPU_FOREACH(cs) {
423 PowerPCCPU *cpu = POWERPC_CPU(cs);
424
425 icp_kvm_realize(DEVICE(spapr_cpu_state(cpu)->icp), &local_err);
426 if (local_err) {
427 goto fail;
428 }
429 }
430
431 /* Update the KVM sources */
432 ics_set_kvm_state(ics, &local_err);
433 if (local_err) {
434 goto fail;
435 }
436
437 /* Connect the presenters to the initial VCPUs of the machine */
438 CPU_FOREACH(cs) {
439 PowerPCCPU *cpu = POWERPC_CPU(cs);
440 icp_set_kvm_state(spapr_cpu_state(cpu)->icp, &local_err);
441 if (local_err) {
442 goto fail;
443 }
444 }
445
446 return 0;
447
448 fail:
449 error_propagate(errp, local_err);
450 xics_kvm_disconnect(intc);
451 return -1;
452 }
453
454 void xics_kvm_disconnect(SpaprInterruptController *intc)
455 {
456 /*
457 * Only on P9 using the XICS-on XIVE KVM device:
458 *
459 * When the KVM device fd is closed, the device is destroyed and
460 * removed from the list of devices of the VM. The VCPU presenters
461 * are also detached from the device.
462 */
463 if (kernel_xics_fd != -1) {
464 close(kernel_xics_fd);
465 kernel_xics_fd = -1;
466 }
467
468 kvmppc_define_rtas_kernel_token(0, "ibm,set-xive");
469 kvmppc_define_rtas_kernel_token(0, "ibm,get-xive");
470 kvmppc_define_rtas_kernel_token(0, "ibm,int-on");
471 kvmppc_define_rtas_kernel_token(0, "ibm,int-off");
472
473 kvm_kernel_irqchip = false;
474 kvm_msi_via_irqfd_allowed = false;
475 kvm_gsi_direct_mapping = false;
476
477 /* Clear the presenter from the VCPUs */
478 kvm_disable_icps();
479 }
480
481 /*
482 * This is a heuristic to detect older KVMs on POWER9 hosts that don't
483 * support destruction of a KVM XICS device while the VM is running.
484 * Required to start a spapr machine with ic-mode=dual,kernel-irqchip=on.
485 */
486 bool xics_kvm_has_broken_disconnect(void)
487 {
488 int rc;
489
490 rc = kvm_create_device(kvm_state, KVM_DEV_TYPE_XICS, false);
491 if (rc < 0) {
492 /*
493 * The error is ignored on purpose. The KVM XICS setup code
494 * will catch it again anyway. The goal here is to see if
495 * close() actually destroys the device or not.
496 */
497 return false;
498 }
499
500 close(rc);
501
502 rc = kvm_create_device(kvm_state, KVM_DEV_TYPE_XICS, false);
503 if (rc >= 0) {
504 close(rc);
505 return false;
506 }
507
508 return errno == EEXIST;
509 }