1 /*
2 * Copyright 2011 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com>
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License, version 2, as
6 * published by the Free Software Foundation.
7 */
8
9 #include <linux/cpu.h>
10 #include <linux/kvm_host.h>
11 #include <linux/preempt.h>
12 #include <linux/export.h>
13 #include <linux/sched.h>
14 #include <linux/spinlock.h>
15 #include <linux/init.h>
16 #include <linux/memblock.h>
17 #include <linux/sizes.h>
18 #include <linux/cma.h>
19 #include <linux/bitops.h>
20
21 #include <asm/asm-prototypes.h>
22 #include <asm/cputable.h>
23 #include <asm/kvm_ppc.h>
24 #include <asm/kvm_book3s.h>
25 #include <asm/archrandom.h>
26 #include <asm/xics.h>
27 #include <asm/xive.h>
28 #include <asm/dbell.h>
29 #include <asm/cputhreads.h>
30 #include <asm/io.h>
31 #include <asm/opal.h>
32 #include <asm/smp.h>
33
34 #define KVM_CMA_CHUNK_ORDER 18
35
36 #include "book3s_xics.h"
37 #include "book3s_xive.h"
38
39 /*
40 * The XIVE module will populate these when it loads
41 */
42 unsigned long (*__xive_vm_h_xirr)(struct kvm_vcpu *vcpu);
43 unsigned long (*__xive_vm_h_ipoll)(struct kvm_vcpu *vcpu, unsigned long server);
44 int (*__xive_vm_h_ipi)(struct kvm_vcpu *vcpu, unsigned long server,
45 unsigned long mfrr);
46 int (*__xive_vm_h_cppr)(struct kvm_vcpu *vcpu, unsigned long cppr);
47 int (*__xive_vm_h_eoi)(struct kvm_vcpu *vcpu, unsigned long xirr);
48 EXPORT_SYMBOL_GPL(__xive_vm_h_xirr);
49 EXPORT_SYMBOL_GPL(__xive_vm_h_ipoll);
50 EXPORT_SYMBOL_GPL(__xive_vm_h_ipi);
51 EXPORT_SYMBOL_GPL(__xive_vm_h_cppr);
52 EXPORT_SYMBOL_GPL(__xive_vm_h_eoi);
53
54 /*
55 * Hash page table alignment on newer cpus(CPU_FTR_ARCH_206)
56 * should be power of 2.
57 */
58 #define HPT_ALIGN_PAGES ((1 << 18) >> PAGE_SHIFT) /* 256k */
59 /*
60 * By default we reserve 5% of memory for hash pagetable allocation.
61 */
62 static unsigned long kvm_cma_resv_ratio = 5;
63
64 static struct cma *kvm_cma;
65
early_parse_kvm_cma_resv(char * p)66 static int __init early_parse_kvm_cma_resv(char *p)
67 {
68 pr_debug("%s(%s)\n", __func__, p);
69 if (!p)
70 return -EINVAL;
71 return kstrtoul(p, 0, &kvm_cma_resv_ratio);
72 }
73 early_param("kvm_cma_resv_ratio", early_parse_kvm_cma_resv);
74
kvm_alloc_hpt_cma(unsigned long nr_pages)75 struct page *kvm_alloc_hpt_cma(unsigned long nr_pages)
76 {
77 VM_BUG_ON(order_base_2(nr_pages) < KVM_CMA_CHUNK_ORDER - PAGE_SHIFT);
78
79 return cma_alloc(kvm_cma, nr_pages, order_base_2(HPT_ALIGN_PAGES),
80 false);
81 }
82 EXPORT_SYMBOL_GPL(kvm_alloc_hpt_cma);
83
kvm_free_hpt_cma(struct page * page,unsigned long nr_pages)84 void kvm_free_hpt_cma(struct page *page, unsigned long nr_pages)
85 {
86 cma_release(kvm_cma, page, nr_pages);
87 }
88 EXPORT_SYMBOL_GPL(kvm_free_hpt_cma);
89
90 /**
91 * kvm_cma_reserve() - reserve area for kvm hash pagetable
92 *
93 * This function reserves memory from early allocator. It should be
94 * called by arch specific code once the memblock allocator
95 * has been activated and all other subsystems have already allocated/reserved
96 * memory.
97 */
kvm_cma_reserve(void)98 void __init kvm_cma_reserve(void)
99 {
100 unsigned long align_size;
101 struct memblock_region *reg;
102 phys_addr_t selected_size = 0;
103
104 /*
105 * We need CMA reservation only when we are in HV mode
106 */
107 if (!cpu_has_feature(CPU_FTR_HVMODE))
108 return;
109 /*
110 * We cannot use memblock_phys_mem_size() here, because
111 * memblock_analyze() has not been called yet.
112 */
113 for_each_memblock(memory, reg)
114 selected_size += memblock_region_memory_end_pfn(reg) -
115 memblock_region_memory_base_pfn(reg);
116
117 selected_size = (selected_size * kvm_cma_resv_ratio / 100) << PAGE_SHIFT;
118 if (selected_size) {
119 pr_debug("%s: reserving %ld MiB for global area\n", __func__,
120 (unsigned long)selected_size / SZ_1M);
121 align_size = HPT_ALIGN_PAGES << PAGE_SHIFT;
122 cma_declare_contiguous(0, selected_size, 0, align_size,
123 KVM_CMA_CHUNK_ORDER - PAGE_SHIFT, false, "kvm_cma",
124 &kvm_cma);
125 }
126 }
127
128 /*
129 * Real-mode H_CONFER implementation.
130 * We check if we are the only vcpu out of this virtual core
131 * still running in the guest and not ceded. If so, we pop up
132 * to the virtual-mode implementation; if not, just return to
133 * the guest.
134 */
kvmppc_rm_h_confer(struct kvm_vcpu * vcpu,int target,unsigned int yield_count)135 long int kvmppc_rm_h_confer(struct kvm_vcpu *vcpu, int target,
136 unsigned int yield_count)
137 {
138 struct kvmppc_vcore *vc = local_paca->kvm_hstate.kvm_vcore;
139 int ptid = local_paca->kvm_hstate.ptid;
140 int threads_running;
141 int threads_ceded;
142 int threads_conferring;
143 u64 stop = get_tb() + 10 * tb_ticks_per_usec;
144 int rv = H_SUCCESS; /* => don't yield */
145
146 set_bit(ptid, &vc->conferring_threads);
147 while ((get_tb() < stop) && !VCORE_IS_EXITING(vc)) {
148 threads_running = VCORE_ENTRY_MAP(vc);
149 threads_ceded = vc->napping_threads;
150 threads_conferring = vc->conferring_threads;
151 if ((threads_ceded | threads_conferring) == threads_running) {
152 rv = H_TOO_HARD; /* => do yield */
153 break;
154 }
155 }
156 clear_bit(ptid, &vc->conferring_threads);
157 return rv;
158 }
159
160 /*
161 * When running HV mode KVM we need to block certain operations while KVM VMs
162 * exist in the system. We use a counter of VMs to track this.
163 *
164 * One of the operations we need to block is onlining of secondaries, so we
165 * protect hv_vm_count with get/put_online_cpus().
166 */
167 static atomic_t hv_vm_count;
168
kvm_hv_vm_activated(void)169 void kvm_hv_vm_activated(void)
170 {
171 get_online_cpus();
172 atomic_inc(&hv_vm_count);
173 put_online_cpus();
174 }
175 EXPORT_SYMBOL_GPL(kvm_hv_vm_activated);
176
kvm_hv_vm_deactivated(void)177 void kvm_hv_vm_deactivated(void)
178 {
179 get_online_cpus();
180 atomic_dec(&hv_vm_count);
181 put_online_cpus();
182 }
183 EXPORT_SYMBOL_GPL(kvm_hv_vm_deactivated);
184
kvm_hv_mode_active(void)185 bool kvm_hv_mode_active(void)
186 {
187 return atomic_read(&hv_vm_count) != 0;
188 }
189
190 extern int hcall_real_table[], hcall_real_table_end[];
191
kvmppc_hcall_impl_hv_realmode(unsigned long cmd)192 int kvmppc_hcall_impl_hv_realmode(unsigned long cmd)
193 {
194 cmd /= 4;
195 if (cmd < hcall_real_table_end - hcall_real_table &&
196 hcall_real_table[cmd])
197 return 1;
198
199 return 0;
200 }
201 EXPORT_SYMBOL_GPL(kvmppc_hcall_impl_hv_realmode);
202
kvmppc_hwrng_present(void)203 int kvmppc_hwrng_present(void)
204 {
205 return powernv_hwrng_present();
206 }
207 EXPORT_SYMBOL_GPL(kvmppc_hwrng_present);
208
kvmppc_h_random(struct kvm_vcpu * vcpu)209 long kvmppc_h_random(struct kvm_vcpu *vcpu)
210 {
211 int r;
212
213 /* Only need to do the expensive mfmsr() on radix */
214 if (kvm_is_radix(vcpu->kvm) && (mfmsr() & MSR_IR))
215 r = powernv_get_random_long(&vcpu->arch.regs.gpr[4]);
216 else
217 r = powernv_get_random_real_mode(&vcpu->arch.regs.gpr[4]);
218 if (r)
219 return H_SUCCESS;
220
221 return H_HARDWARE;
222 }
223
224 /*
225 * Send an interrupt or message to another CPU.
226 * The caller needs to include any barrier needed to order writes
227 * to memory vs. the IPI/message.
228 */
kvmhv_rm_send_ipi(int cpu)229 void kvmhv_rm_send_ipi(int cpu)
230 {
231 void __iomem *xics_phys;
232 unsigned long msg = PPC_DBELL_TYPE(PPC_DBELL_SERVER);
233
234 /* On POWER9 we can use msgsnd for any destination cpu. */
235 if (cpu_has_feature(CPU_FTR_ARCH_300)) {
236 msg |= get_hard_smp_processor_id(cpu);
237 __asm__ __volatile__ (PPC_MSGSND(%0) : : "r" (msg));
238 return;
239 }
240
241 /* On POWER8 for IPIs to threads in the same core, use msgsnd. */
242 if (cpu_has_feature(CPU_FTR_ARCH_207S) &&
243 cpu_first_thread_sibling(cpu) ==
244 cpu_first_thread_sibling(raw_smp_processor_id())) {
245 msg |= cpu_thread_in_core(cpu);
246 __asm__ __volatile__ (PPC_MSGSND(%0) : : "r" (msg));
247 return;
248 }
249
250 /* We should never reach this */
251 if (WARN_ON_ONCE(xive_enabled()))
252 return;
253
254 /* Else poke the target with an IPI */
255 xics_phys = paca_ptrs[cpu]->kvm_hstate.xics_phys;
256 if (xics_phys)
257 __raw_rm_writeb(IPI_PRIORITY, xics_phys + XICS_MFRR);
258 else
259 opal_int_set_mfrr(get_hard_smp_processor_id(cpu), IPI_PRIORITY);
260 }
261
262 /*
263 * The following functions are called from the assembly code
264 * in book3s_hv_rmhandlers.S.
265 */
kvmhv_interrupt_vcore(struct kvmppc_vcore * vc,int active)266 static void kvmhv_interrupt_vcore(struct kvmppc_vcore *vc, int active)
267 {
268 int cpu = vc->pcpu;
269
270 /* Order setting of exit map vs. msgsnd/IPI */
271 smp_mb();
272 for (; active; active >>= 1, ++cpu)
273 if (active & 1)
274 kvmhv_rm_send_ipi(cpu);
275 }
276
kvmhv_commence_exit(int trap)277 void kvmhv_commence_exit(int trap)
278 {
279 struct kvmppc_vcore *vc = local_paca->kvm_hstate.kvm_vcore;
280 int ptid = local_paca->kvm_hstate.ptid;
281 struct kvm_split_mode *sip = local_paca->kvm_hstate.kvm_split_mode;
282 int me, ee, i, t;
283 int cpu0;
284
285 /* Set our bit in the threads-exiting-guest map in the 0xff00
286 bits of vcore->entry_exit_map */
287 me = 0x100 << ptid;
288 do {
289 ee = vc->entry_exit_map;
290 } while (cmpxchg(&vc->entry_exit_map, ee, ee | me) != ee);
291
292 /* Are we the first here? */
293 if ((ee >> 8) != 0)
294 return;
295
296 /*
297 * Trigger the other threads in this vcore to exit the guest.
298 * If this is a hypervisor decrementer interrupt then they
299 * will be already on their way out of the guest.
300 */
301 if (trap != BOOK3S_INTERRUPT_HV_DECREMENTER)
302 kvmhv_interrupt_vcore(vc, ee & ~(1 << ptid));
303
304 /*
305 * If we are doing dynamic micro-threading, interrupt the other
306 * subcores to pull them out of their guests too.
307 */
308 if (!sip)
309 return;
310
311 for (i = 0; i < MAX_SUBCORES; ++i) {
312 vc = sip->vc[i];
313 if (!vc)
314 break;
315 do {
316 ee = vc->entry_exit_map;
317 /* Already asked to exit? */
318 if ((ee >> 8) != 0)
319 break;
320 } while (cmpxchg(&vc->entry_exit_map, ee,
321 ee | VCORE_EXIT_REQ) != ee);
322 if ((ee >> 8) == 0)
323 kvmhv_interrupt_vcore(vc, ee);
324 }
325
326 /*
327 * On POWER9 when running a HPT guest on a radix host (sip != NULL),
328 * we have to interrupt inactive CPU threads to get them to
329 * restore the host LPCR value.
330 */
331 if (sip->lpcr_req) {
332 if (cmpxchg(&sip->do_restore, 0, 1) == 0) {
333 vc = local_paca->kvm_hstate.kvm_vcore;
334 cpu0 = vc->pcpu + ptid - local_paca->kvm_hstate.tid;
335 for (t = 1; t < threads_per_core; ++t) {
336 if (sip->napped[t])
337 kvmhv_rm_send_ipi(cpu0 + t);
338 }
339 }
340 }
341 }
342
343 struct kvmppc_host_rm_ops *kvmppc_host_rm_ops_hv;
344 EXPORT_SYMBOL_GPL(kvmppc_host_rm_ops_hv);
345
346 #ifdef CONFIG_KVM_XICS
get_irqmap(struct kvmppc_passthru_irqmap * pimap,u32 xisr)347 static struct kvmppc_irq_map *get_irqmap(struct kvmppc_passthru_irqmap *pimap,
348 u32 xisr)
349 {
350 int i;
351
352 /*
353 * We access the mapped array here without a lock. That
354 * is safe because we never reduce the number of entries
355 * in the array and we never change the v_hwirq field of
356 * an entry once it is set.
357 *
358 * We have also carefully ordered the stores in the writer
359 * and the loads here in the reader, so that if we find a matching
360 * hwirq here, the associated GSI and irq_desc fields are valid.
361 */
362 for (i = 0; i < pimap->n_mapped; i++) {
363 if (xisr == pimap->mapped[i].r_hwirq) {
364 /*
365 * Order subsequent reads in the caller to serialize
366 * with the writer.
367 */
368 smp_rmb();
369 return &pimap->mapped[i];
370 }
371 }
372 return NULL;
373 }
374
375 /*
376 * If we have an interrupt that's not an IPI, check if we have a
377 * passthrough adapter and if so, check if this external interrupt
378 * is for the adapter.
379 * We will attempt to deliver the IRQ directly to the target VCPU's
380 * ICP, the virtual ICP (based on affinity - the xive value in ICS).
381 *
382 * If the delivery fails or if this is not for a passthrough adapter,
383 * return to the host to handle this interrupt. We earlier
384 * saved a copy of the XIRR in the PACA, it will be picked up by
385 * the host ICP driver.
386 */
kvmppc_check_passthru(u32 xisr,__be32 xirr,bool * again)387 static int kvmppc_check_passthru(u32 xisr, __be32 xirr, bool *again)
388 {
389 struct kvmppc_passthru_irqmap *pimap;
390 struct kvmppc_irq_map *irq_map;
391 struct kvm_vcpu *vcpu;
392
393 vcpu = local_paca->kvm_hstate.kvm_vcpu;
394 if (!vcpu)
395 return 1;
396 pimap = kvmppc_get_passthru_irqmap(vcpu->kvm);
397 if (!pimap)
398 return 1;
399 irq_map = get_irqmap(pimap, xisr);
400 if (!irq_map)
401 return 1;
402
403 /* We're handling this interrupt, generic code doesn't need to */
404 local_paca->kvm_hstate.saved_xirr = 0;
405
406 return kvmppc_deliver_irq_passthru(vcpu, xirr, irq_map, pimap, again);
407 }
408
409 #else
kvmppc_check_passthru(u32 xisr,__be32 xirr,bool * again)410 static inline int kvmppc_check_passthru(u32 xisr, __be32 xirr, bool *again)
411 {
412 return 1;
413 }
414 #endif
415
416 /*
417 * Determine what sort of external interrupt is pending (if any).
418 * Returns:
419 * 0 if no interrupt is pending
420 * 1 if an interrupt is pending that needs to be handled by the host
421 * 2 Passthrough that needs completion in the host
422 * -1 if there was a guest wakeup IPI (which has now been cleared)
423 * -2 if there is PCI passthrough external interrupt that was handled
424 */
425 static long kvmppc_read_one_intr(bool *again);
426
kvmppc_read_intr(void)427 long kvmppc_read_intr(void)
428 {
429 long ret = 0;
430 long rc;
431 bool again;
432
433 if (xive_enabled())
434 return 1;
435
436 do {
437 again = false;
438 rc = kvmppc_read_one_intr(&again);
439 if (rc && (ret == 0 || rc > ret))
440 ret = rc;
441 } while (again);
442 return ret;
443 }
444
kvmppc_read_one_intr(bool * again)445 static long kvmppc_read_one_intr(bool *again)
446 {
447 void __iomem *xics_phys;
448 u32 h_xirr;
449 __be32 xirr;
450 u32 xisr;
451 u8 host_ipi;
452 int64_t rc;
453
454 if (xive_enabled())
455 return 1;
456
457 /* see if a host IPI is pending */
458 host_ipi = local_paca->kvm_hstate.host_ipi;
459 if (host_ipi)
460 return 1;
461
462 /* Now read the interrupt from the ICP */
463 xics_phys = local_paca->kvm_hstate.xics_phys;
464 rc = 0;
465 if (!xics_phys)
466 rc = opal_int_get_xirr(&xirr, false);
467 else
468 xirr = __raw_rm_readl(xics_phys + XICS_XIRR);
469 if (rc < 0)
470 return 1;
471
472 /*
473 * Save XIRR for later. Since we get control in reverse endian
474 * on LE systems, save it byte reversed and fetch it back in
475 * host endian. Note that xirr is the value read from the
476 * XIRR register, while h_xirr is the host endian version.
477 */
478 h_xirr = be32_to_cpu(xirr);
479 local_paca->kvm_hstate.saved_xirr = h_xirr;
480 xisr = h_xirr & 0xffffff;
481 /*
482 * Ensure that the store/load complete to guarantee all side
483 * effects of loading from XIRR has completed
484 */
485 smp_mb();
486
487 /* if nothing pending in the ICP */
488 if (!xisr)
489 return 0;
490
491 /* We found something in the ICP...
492 *
493 * If it is an IPI, clear the MFRR and EOI it.
494 */
495 if (xisr == XICS_IPI) {
496 rc = 0;
497 if (xics_phys) {
498 __raw_rm_writeb(0xff, xics_phys + XICS_MFRR);
499 __raw_rm_writel(xirr, xics_phys + XICS_XIRR);
500 } else {
501 opal_int_set_mfrr(hard_smp_processor_id(), 0xff);
502 rc = opal_int_eoi(h_xirr);
503 }
504 /* If rc > 0, there is another interrupt pending */
505 *again = rc > 0;
506
507 /*
508 * Need to ensure side effects of above stores
509 * complete before proceeding.
510 */
511 smp_mb();
512
513 /*
514 * We need to re-check host IPI now in case it got set in the
515 * meantime. If it's clear, we bounce the interrupt to the
516 * guest
517 */
518 host_ipi = local_paca->kvm_hstate.host_ipi;
519 if (unlikely(host_ipi != 0)) {
520 /* We raced with the host,
521 * we need to resend that IPI, bummer
522 */
523 if (xics_phys)
524 __raw_rm_writeb(IPI_PRIORITY,
525 xics_phys + XICS_MFRR);
526 else
527 opal_int_set_mfrr(hard_smp_processor_id(),
528 IPI_PRIORITY);
529 /* Let side effects complete */
530 smp_mb();
531 return 1;
532 }
533
534 /* OK, it's an IPI for us */
535 local_paca->kvm_hstate.saved_xirr = 0;
536 return -1;
537 }
538
539 return kvmppc_check_passthru(xisr, xirr, again);
540 }
541
542 #ifdef CONFIG_KVM_XICS
is_rm(void)543 static inline bool is_rm(void)
544 {
545 return !(mfmsr() & MSR_DR);
546 }
547
kvmppc_rm_h_xirr(struct kvm_vcpu * vcpu)548 unsigned long kvmppc_rm_h_xirr(struct kvm_vcpu *vcpu)
549 {
550 if (!kvmppc_xics_enabled(vcpu))
551 return H_TOO_HARD;
552 if (xive_enabled()) {
553 if (is_rm())
554 return xive_rm_h_xirr(vcpu);
555 if (unlikely(!__xive_vm_h_xirr))
556 return H_NOT_AVAILABLE;
557 return __xive_vm_h_xirr(vcpu);
558 } else
559 return xics_rm_h_xirr(vcpu);
560 }
561
kvmppc_rm_h_xirr_x(struct kvm_vcpu * vcpu)562 unsigned long kvmppc_rm_h_xirr_x(struct kvm_vcpu *vcpu)
563 {
564 if (!kvmppc_xics_enabled(vcpu))
565 return H_TOO_HARD;
566 vcpu->arch.regs.gpr[5] = get_tb();
567 if (xive_enabled()) {
568 if (is_rm())
569 return xive_rm_h_xirr(vcpu);
570 if (unlikely(!__xive_vm_h_xirr))
571 return H_NOT_AVAILABLE;
572 return __xive_vm_h_xirr(vcpu);
573 } else
574 return xics_rm_h_xirr(vcpu);
575 }
576
kvmppc_rm_h_ipoll(struct kvm_vcpu * vcpu,unsigned long server)577 unsigned long kvmppc_rm_h_ipoll(struct kvm_vcpu *vcpu, unsigned long server)
578 {
579 if (!kvmppc_xics_enabled(vcpu))
580 return H_TOO_HARD;
581 if (xive_enabled()) {
582 if (is_rm())
583 return xive_rm_h_ipoll(vcpu, server);
584 if (unlikely(!__xive_vm_h_ipoll))
585 return H_NOT_AVAILABLE;
586 return __xive_vm_h_ipoll(vcpu, server);
587 } else
588 return H_TOO_HARD;
589 }
590
kvmppc_rm_h_ipi(struct kvm_vcpu * vcpu,unsigned long server,unsigned long mfrr)591 int kvmppc_rm_h_ipi(struct kvm_vcpu *vcpu, unsigned long server,
592 unsigned long mfrr)
593 {
594 if (!kvmppc_xics_enabled(vcpu))
595 return H_TOO_HARD;
596 if (xive_enabled()) {
597 if (is_rm())
598 return xive_rm_h_ipi(vcpu, server, mfrr);
599 if (unlikely(!__xive_vm_h_ipi))
600 return H_NOT_AVAILABLE;
601 return __xive_vm_h_ipi(vcpu, server, mfrr);
602 } else
603 return xics_rm_h_ipi(vcpu, server, mfrr);
604 }
605
kvmppc_rm_h_cppr(struct kvm_vcpu * vcpu,unsigned long cppr)606 int kvmppc_rm_h_cppr(struct kvm_vcpu *vcpu, unsigned long cppr)
607 {
608 if (!kvmppc_xics_enabled(vcpu))
609 return H_TOO_HARD;
610 if (xive_enabled()) {
611 if (is_rm())
612 return xive_rm_h_cppr(vcpu, cppr);
613 if (unlikely(!__xive_vm_h_cppr))
614 return H_NOT_AVAILABLE;
615 return __xive_vm_h_cppr(vcpu, cppr);
616 } else
617 return xics_rm_h_cppr(vcpu, cppr);
618 }
619
kvmppc_rm_h_eoi(struct kvm_vcpu * vcpu,unsigned long xirr)620 int kvmppc_rm_h_eoi(struct kvm_vcpu *vcpu, unsigned long xirr)
621 {
622 if (!kvmppc_xics_enabled(vcpu))
623 return H_TOO_HARD;
624 if (xive_enabled()) {
625 if (is_rm())
626 return xive_rm_h_eoi(vcpu, xirr);
627 if (unlikely(!__xive_vm_h_eoi))
628 return H_NOT_AVAILABLE;
629 return __xive_vm_h_eoi(vcpu, xirr);
630 } else
631 return xics_rm_h_eoi(vcpu, xirr);
632 }
633 #endif /* CONFIG_KVM_XICS */
634
kvmppc_bad_interrupt(struct pt_regs * regs)635 void kvmppc_bad_interrupt(struct pt_regs *regs)
636 {
637 /*
638 * 100 could happen at any time, 200 can happen due to invalid real
639 * address access for example (or any time due to a hardware problem).
640 */
641 if (TRAP(regs) == 0x100) {
642 get_paca()->in_nmi++;
643 system_reset_exception(regs);
644 get_paca()->in_nmi--;
645 } else if (TRAP(regs) == 0x200) {
646 machine_check_exception(regs);
647 } else {
648 die("Bad interrupt in KVM entry/exit code", regs, SIGABRT);
649 }
650 panic("Bad KVM trap");
651 }
652
653 /*
654 * Functions used to switch LPCR HR and UPRT bits on all threads
655 * when entering and exiting HPT guests on a radix host.
656 */
657
658 #define PHASE_REALMODE 1 /* in real mode */
659 #define PHASE_SET_LPCR 2 /* have set LPCR */
660 #define PHASE_OUT_OF_GUEST 4 /* have finished executing in guest */
661 #define PHASE_RESET_LPCR 8 /* have reset LPCR to host value */
662
663 #define ALL(p) (((p) << 24) | ((p) << 16) | ((p) << 8) | (p))
664
wait_for_sync(struct kvm_split_mode * sip,int phase)665 static void wait_for_sync(struct kvm_split_mode *sip, int phase)
666 {
667 int thr = local_paca->kvm_hstate.tid;
668
669 sip->lpcr_sync.phase[thr] |= phase;
670 phase = ALL(phase);
671 while ((sip->lpcr_sync.allphases & phase) != phase) {
672 HMT_low();
673 barrier();
674 }
675 HMT_medium();
676 }
677
kvmhv_p9_set_lpcr(struct kvm_split_mode * sip)678 void kvmhv_p9_set_lpcr(struct kvm_split_mode *sip)
679 {
680 unsigned long rb, set;
681
682 /* wait for every other thread to get to real mode */
683 wait_for_sync(sip, PHASE_REALMODE);
684
685 /* Set LPCR and LPIDR */
686 mtspr(SPRN_LPCR, sip->lpcr_req);
687 mtspr(SPRN_LPID, sip->lpidr_req);
688 isync();
689
690 /* Invalidate the TLB on thread 0 */
691 if (local_paca->kvm_hstate.tid == 0) {
692 sip->do_set = 0;
693 asm volatile("ptesync" : : : "memory");
694 for (set = 0; set < POWER9_TLB_SETS_RADIX; ++set) {
695 rb = TLBIEL_INVAL_SET_LPID +
696 (set << TLBIEL_INVAL_SET_SHIFT);
697 asm volatile(PPC_TLBIEL(%0, %1, 0, 0, 0) : :
698 "r" (rb), "r" (0));
699 }
700 asm volatile("ptesync" : : : "memory");
701 }
702
703 /* indicate that we have done so and wait for others */
704 wait_for_sync(sip, PHASE_SET_LPCR);
705 /* order read of sip->lpcr_sync.allphases vs. sip->do_set */
706 smp_rmb();
707 }
708
709 /*
710 * Called when a thread that has been in the guest needs
711 * to reload the host LPCR value - but only on POWER9 when
712 * running a HPT guest on a radix host.
713 */
kvmhv_p9_restore_lpcr(struct kvm_split_mode * sip)714 void kvmhv_p9_restore_lpcr(struct kvm_split_mode *sip)
715 {
716 /* we're out of the guest... */
717 wait_for_sync(sip, PHASE_OUT_OF_GUEST);
718
719 mtspr(SPRN_LPID, 0);
720 mtspr(SPRN_LPCR, sip->host_lpcr);
721 isync();
722
723 if (local_paca->kvm_hstate.tid == 0) {
724 sip->do_restore = 0;
725 smp_wmb(); /* order store of do_restore vs. phase */
726 }
727
728 wait_for_sync(sip, PHASE_RESET_LPCR);
729 smp_mb();
730 local_paca->kvm_hstate.kvm_split_mode = NULL;
731 }
732