1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright 2011 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com> 4 */ 5 6 #include <linux/cpu.h> 7 #include <linux/kvm_host.h> 8 #include <linux/preempt.h> 9 #include <linux/export.h> 10 #include <linux/sched.h> 11 #include <linux/spinlock.h> 12 #include <linux/init.h> 13 #include <linux/memblock.h> 14 #include <linux/sizes.h> 15 #include <linux/cma.h> 16 #include <linux/bitops.h> 17 18 #include <asm/asm-prototypes.h> 19 #include <asm/cputable.h> 20 #include <asm/kvm_ppc.h> 21 #include <asm/kvm_book3s.h> 22 #include <asm/archrandom.h> 23 #include <asm/xics.h> 24 #include <asm/xive.h> 25 #include <asm/dbell.h> 26 #include <asm/cputhreads.h> 27 #include <asm/io.h> 28 #include <asm/opal.h> 29 #include <asm/smp.h> 30 31 #define KVM_CMA_CHUNK_ORDER 18 32 33 #include "book3s_xics.h" 34 #include "book3s_xive.h" 35 36 /* 37 * The XIVE module will populate these when it loads 38 */ 39 unsigned long (*__xive_vm_h_xirr)(struct kvm_vcpu *vcpu); 40 unsigned long (*__xive_vm_h_ipoll)(struct kvm_vcpu *vcpu, unsigned long server); 41 int (*__xive_vm_h_ipi)(struct kvm_vcpu *vcpu, unsigned long server, 42 unsigned long mfrr); 43 int (*__xive_vm_h_cppr)(struct kvm_vcpu *vcpu, unsigned long cppr); 44 int (*__xive_vm_h_eoi)(struct kvm_vcpu *vcpu, unsigned long xirr); 45 EXPORT_SYMBOL_GPL(__xive_vm_h_xirr); 46 EXPORT_SYMBOL_GPL(__xive_vm_h_ipoll); 47 EXPORT_SYMBOL_GPL(__xive_vm_h_ipi); 48 EXPORT_SYMBOL_GPL(__xive_vm_h_cppr); 49 EXPORT_SYMBOL_GPL(__xive_vm_h_eoi); 50 51 /* 52 * Hash page table alignment on newer cpus(CPU_FTR_ARCH_206) 53 * should be power of 2. 54 */ 55 #define HPT_ALIGN_PAGES ((1 << 18) >> PAGE_SHIFT) /* 256k */ 56 /* 57 * By default we reserve 5% of memory for hash pagetable allocation. 58 */ 59 static unsigned long kvm_cma_resv_ratio = 5; 60 61 static struct cma *kvm_cma; 62 63 static int __init early_parse_kvm_cma_resv(char *p) 64 { 65 pr_debug("%s(%s)\n", __func__, p); 66 if (!p) 67 return -EINVAL; 68 return kstrtoul(p, 0, &kvm_cma_resv_ratio); 69 } 70 early_param("kvm_cma_resv_ratio", early_parse_kvm_cma_resv); 71 72 struct page *kvm_alloc_hpt_cma(unsigned long nr_pages) 73 { 74 VM_BUG_ON(order_base_2(nr_pages) < KVM_CMA_CHUNK_ORDER - PAGE_SHIFT); 75 76 return cma_alloc(kvm_cma, nr_pages, order_base_2(HPT_ALIGN_PAGES), 77 false); 78 } 79 EXPORT_SYMBOL_GPL(kvm_alloc_hpt_cma); 80 81 void kvm_free_hpt_cma(struct page *page, unsigned long nr_pages) 82 { 83 cma_release(kvm_cma, page, nr_pages); 84 } 85 EXPORT_SYMBOL_GPL(kvm_free_hpt_cma); 86 87 /** 88 * kvm_cma_reserve() - reserve area for kvm hash pagetable 89 * 90 * This function reserves memory from early allocator. It should be 91 * called by arch specific code once the memblock allocator 92 * has been activated and all other subsystems have already allocated/reserved 93 * memory. 94 */ 95 void __init kvm_cma_reserve(void) 96 { 97 unsigned long align_size; 98 struct memblock_region *reg; 99 phys_addr_t selected_size = 0; 100 101 /* 102 * We need CMA reservation only when we are in HV mode 103 */ 104 if (!cpu_has_feature(CPU_FTR_HVMODE)) 105 return; 106 /* 107 * We cannot use memblock_phys_mem_size() here, because 108 * memblock_analyze() has not been called yet. 109 */ 110 for_each_memblock(memory, reg) 111 selected_size += memblock_region_memory_end_pfn(reg) - 112 memblock_region_memory_base_pfn(reg); 113 114 selected_size = (selected_size * kvm_cma_resv_ratio / 100) << PAGE_SHIFT; 115 if (selected_size) { 116 pr_debug("%s: reserving %ld MiB for global area\n", __func__, 117 (unsigned long)selected_size / SZ_1M); 118 align_size = HPT_ALIGN_PAGES << PAGE_SHIFT; 119 cma_declare_contiguous(0, selected_size, 0, align_size, 120 KVM_CMA_CHUNK_ORDER - PAGE_SHIFT, false, "kvm_cma", 121 &kvm_cma); 122 } 123 } 124 125 /* 126 * Real-mode H_CONFER implementation. 127 * We check if we are the only vcpu out of this virtual core 128 * still running in the guest and not ceded. If so, we pop up 129 * to the virtual-mode implementation; if not, just return to 130 * the guest. 131 */ 132 long int kvmppc_rm_h_confer(struct kvm_vcpu *vcpu, int target, 133 unsigned int yield_count) 134 { 135 struct kvmppc_vcore *vc = local_paca->kvm_hstate.kvm_vcore; 136 int ptid = local_paca->kvm_hstate.ptid; 137 int threads_running; 138 int threads_ceded; 139 int threads_conferring; 140 u64 stop = get_tb() + 10 * tb_ticks_per_usec; 141 int rv = H_SUCCESS; /* => don't yield */ 142 143 set_bit(ptid, &vc->conferring_threads); 144 while ((get_tb() < stop) && !VCORE_IS_EXITING(vc)) { 145 threads_running = VCORE_ENTRY_MAP(vc); 146 threads_ceded = vc->napping_threads; 147 threads_conferring = vc->conferring_threads; 148 if ((threads_ceded | threads_conferring) == threads_running) { 149 rv = H_TOO_HARD; /* => do yield */ 150 break; 151 } 152 } 153 clear_bit(ptid, &vc->conferring_threads); 154 return rv; 155 } 156 157 /* 158 * When running HV mode KVM we need to block certain operations while KVM VMs 159 * exist in the system. We use a counter of VMs to track this. 160 * 161 * One of the operations we need to block is onlining of secondaries, so we 162 * protect hv_vm_count with get/put_online_cpus(). 163 */ 164 static atomic_t hv_vm_count; 165 166 void kvm_hv_vm_activated(void) 167 { 168 get_online_cpus(); 169 atomic_inc(&hv_vm_count); 170 put_online_cpus(); 171 } 172 EXPORT_SYMBOL_GPL(kvm_hv_vm_activated); 173 174 void kvm_hv_vm_deactivated(void) 175 { 176 get_online_cpus(); 177 atomic_dec(&hv_vm_count); 178 put_online_cpus(); 179 } 180 EXPORT_SYMBOL_GPL(kvm_hv_vm_deactivated); 181 182 bool kvm_hv_mode_active(void) 183 { 184 return atomic_read(&hv_vm_count) != 0; 185 } 186 187 extern int hcall_real_table[], hcall_real_table_end[]; 188 189 int kvmppc_hcall_impl_hv_realmode(unsigned long cmd) 190 { 191 cmd /= 4; 192 if (cmd < hcall_real_table_end - hcall_real_table && 193 hcall_real_table[cmd]) 194 return 1; 195 196 return 0; 197 } 198 EXPORT_SYMBOL_GPL(kvmppc_hcall_impl_hv_realmode); 199 200 int kvmppc_hwrng_present(void) 201 { 202 return powernv_hwrng_present(); 203 } 204 EXPORT_SYMBOL_GPL(kvmppc_hwrng_present); 205 206 long kvmppc_h_random(struct kvm_vcpu *vcpu) 207 { 208 int r; 209 210 /* Only need to do the expensive mfmsr() on radix */ 211 if (kvm_is_radix(vcpu->kvm) && (mfmsr() & MSR_IR)) 212 r = powernv_get_random_long(&vcpu->arch.regs.gpr[4]); 213 else 214 r = powernv_get_random_real_mode(&vcpu->arch.regs.gpr[4]); 215 if (r) 216 return H_SUCCESS; 217 218 return H_HARDWARE; 219 } 220 221 /* 222 * Send an interrupt or message to another CPU. 223 * The caller needs to include any barrier needed to order writes 224 * to memory vs. the IPI/message. 225 */ 226 void kvmhv_rm_send_ipi(int cpu) 227 { 228 void __iomem *xics_phys; 229 unsigned long msg = PPC_DBELL_TYPE(PPC_DBELL_SERVER); 230 231 /* For a nested hypervisor, use the XICS via hcall */ 232 if (kvmhv_on_pseries()) { 233 unsigned long retbuf[PLPAR_HCALL_BUFSIZE]; 234 235 plpar_hcall_raw(H_IPI, retbuf, get_hard_smp_processor_id(cpu), 236 IPI_PRIORITY); 237 return; 238 } 239 240 /* On POWER9 we can use msgsnd for any destination cpu. */ 241 if (cpu_has_feature(CPU_FTR_ARCH_300)) { 242 msg |= get_hard_smp_processor_id(cpu); 243 __asm__ __volatile__ (PPC_MSGSND(%0) : : "r" (msg)); 244 return; 245 } 246 247 /* On POWER8 for IPIs to threads in the same core, use msgsnd. */ 248 if (cpu_has_feature(CPU_FTR_ARCH_207S) && 249 cpu_first_thread_sibling(cpu) == 250 cpu_first_thread_sibling(raw_smp_processor_id())) { 251 msg |= cpu_thread_in_core(cpu); 252 __asm__ __volatile__ (PPC_MSGSND(%0) : : "r" (msg)); 253 return; 254 } 255 256 /* We should never reach this */ 257 if (WARN_ON_ONCE(xics_on_xive())) 258 return; 259 260 /* Else poke the target with an IPI */ 261 xics_phys = paca_ptrs[cpu]->kvm_hstate.xics_phys; 262 if (xics_phys) 263 __raw_rm_writeb(IPI_PRIORITY, xics_phys + XICS_MFRR); 264 else 265 opal_int_set_mfrr(get_hard_smp_processor_id(cpu), IPI_PRIORITY); 266 } 267 268 /* 269 * The following functions are called from the assembly code 270 * in book3s_hv_rmhandlers.S. 271 */ 272 static void kvmhv_interrupt_vcore(struct kvmppc_vcore *vc, int active) 273 { 274 int cpu = vc->pcpu; 275 276 /* Order setting of exit map vs. msgsnd/IPI */ 277 smp_mb(); 278 for (; active; active >>= 1, ++cpu) 279 if (active & 1) 280 kvmhv_rm_send_ipi(cpu); 281 } 282 283 void kvmhv_commence_exit(int trap) 284 { 285 struct kvmppc_vcore *vc = local_paca->kvm_hstate.kvm_vcore; 286 int ptid = local_paca->kvm_hstate.ptid; 287 struct kvm_split_mode *sip = local_paca->kvm_hstate.kvm_split_mode; 288 int me, ee, i, t; 289 int cpu0; 290 291 /* Set our bit in the threads-exiting-guest map in the 0xff00 292 bits of vcore->entry_exit_map */ 293 me = 0x100 << ptid; 294 do { 295 ee = vc->entry_exit_map; 296 } while (cmpxchg(&vc->entry_exit_map, ee, ee | me) != ee); 297 298 /* Are we the first here? */ 299 if ((ee >> 8) != 0) 300 return; 301 302 /* 303 * Trigger the other threads in this vcore to exit the guest. 304 * If this is a hypervisor decrementer interrupt then they 305 * will be already on their way out of the guest. 306 */ 307 if (trap != BOOK3S_INTERRUPT_HV_DECREMENTER) 308 kvmhv_interrupt_vcore(vc, ee & ~(1 << ptid)); 309 310 /* 311 * If we are doing dynamic micro-threading, interrupt the other 312 * subcores to pull them out of their guests too. 313 */ 314 if (!sip) 315 return; 316 317 for (i = 0; i < MAX_SUBCORES; ++i) { 318 vc = sip->vc[i]; 319 if (!vc) 320 break; 321 do { 322 ee = vc->entry_exit_map; 323 /* Already asked to exit? */ 324 if ((ee >> 8) != 0) 325 break; 326 } while (cmpxchg(&vc->entry_exit_map, ee, 327 ee | VCORE_EXIT_REQ) != ee); 328 if ((ee >> 8) == 0) 329 kvmhv_interrupt_vcore(vc, ee); 330 } 331 332 /* 333 * On POWER9 when running a HPT guest on a radix host (sip != NULL), 334 * we have to interrupt inactive CPU threads to get them to 335 * restore the host LPCR value. 336 */ 337 if (sip->lpcr_req) { 338 if (cmpxchg(&sip->do_restore, 0, 1) == 0) { 339 vc = local_paca->kvm_hstate.kvm_vcore; 340 cpu0 = vc->pcpu + ptid - local_paca->kvm_hstate.tid; 341 for (t = 1; t < threads_per_core; ++t) { 342 if (sip->napped[t]) 343 kvmhv_rm_send_ipi(cpu0 + t); 344 } 345 } 346 } 347 } 348 349 struct kvmppc_host_rm_ops *kvmppc_host_rm_ops_hv; 350 EXPORT_SYMBOL_GPL(kvmppc_host_rm_ops_hv); 351 352 #ifdef CONFIG_KVM_XICS 353 static struct kvmppc_irq_map *get_irqmap(struct kvmppc_passthru_irqmap *pimap, 354 u32 xisr) 355 { 356 int i; 357 358 /* 359 * We access the mapped array here without a lock. That 360 * is safe because we never reduce the number of entries 361 * in the array and we never change the v_hwirq field of 362 * an entry once it is set. 363 * 364 * We have also carefully ordered the stores in the writer 365 * and the loads here in the reader, so that if we find a matching 366 * hwirq here, the associated GSI and irq_desc fields are valid. 367 */ 368 for (i = 0; i < pimap->n_mapped; i++) { 369 if (xisr == pimap->mapped[i].r_hwirq) { 370 /* 371 * Order subsequent reads in the caller to serialize 372 * with the writer. 373 */ 374 smp_rmb(); 375 return &pimap->mapped[i]; 376 } 377 } 378 return NULL; 379 } 380 381 /* 382 * If we have an interrupt that's not an IPI, check if we have a 383 * passthrough adapter and if so, check if this external interrupt 384 * is for the adapter. 385 * We will attempt to deliver the IRQ directly to the target VCPU's 386 * ICP, the virtual ICP (based on affinity - the xive value in ICS). 387 * 388 * If the delivery fails or if this is not for a passthrough adapter, 389 * return to the host to handle this interrupt. We earlier 390 * saved a copy of the XIRR in the PACA, it will be picked up by 391 * the host ICP driver. 392 */ 393 static int kvmppc_check_passthru(u32 xisr, __be32 xirr, bool *again) 394 { 395 struct kvmppc_passthru_irqmap *pimap; 396 struct kvmppc_irq_map *irq_map; 397 struct kvm_vcpu *vcpu; 398 399 vcpu = local_paca->kvm_hstate.kvm_vcpu; 400 if (!vcpu) 401 return 1; 402 pimap = kvmppc_get_passthru_irqmap(vcpu->kvm); 403 if (!pimap) 404 return 1; 405 irq_map = get_irqmap(pimap, xisr); 406 if (!irq_map) 407 return 1; 408 409 /* We're handling this interrupt, generic code doesn't need to */ 410 local_paca->kvm_hstate.saved_xirr = 0; 411 412 return kvmppc_deliver_irq_passthru(vcpu, xirr, irq_map, pimap, again); 413 } 414 415 #else 416 static inline int kvmppc_check_passthru(u32 xisr, __be32 xirr, bool *again) 417 { 418 return 1; 419 } 420 #endif 421 422 /* 423 * Determine what sort of external interrupt is pending (if any). 424 * Returns: 425 * 0 if no interrupt is pending 426 * 1 if an interrupt is pending that needs to be handled by the host 427 * 2 Passthrough that needs completion in the host 428 * -1 if there was a guest wakeup IPI (which has now been cleared) 429 * -2 if there is PCI passthrough external interrupt that was handled 430 */ 431 static long kvmppc_read_one_intr(bool *again); 432 433 long kvmppc_read_intr(void) 434 { 435 long ret = 0; 436 long rc; 437 bool again; 438 439 if (xive_enabled()) 440 return 1; 441 442 do { 443 again = false; 444 rc = kvmppc_read_one_intr(&again); 445 if (rc && (ret == 0 || rc > ret)) 446 ret = rc; 447 } while (again); 448 return ret; 449 } 450 451 static long kvmppc_read_one_intr(bool *again) 452 { 453 void __iomem *xics_phys; 454 u32 h_xirr; 455 __be32 xirr; 456 u32 xisr; 457 u8 host_ipi; 458 int64_t rc; 459 460 if (xive_enabled()) 461 return 1; 462 463 /* see if a host IPI is pending */ 464 host_ipi = local_paca->kvm_hstate.host_ipi; 465 if (host_ipi) 466 return 1; 467 468 /* Now read the interrupt from the ICP */ 469 if (kvmhv_on_pseries()) { 470 unsigned long retbuf[PLPAR_HCALL_BUFSIZE]; 471 472 rc = plpar_hcall_raw(H_XIRR, retbuf, 0xFF); 473 xirr = cpu_to_be32(retbuf[0]); 474 } else { 475 xics_phys = local_paca->kvm_hstate.xics_phys; 476 rc = 0; 477 if (!xics_phys) 478 rc = opal_int_get_xirr(&xirr, false); 479 else 480 xirr = __raw_rm_readl(xics_phys + XICS_XIRR); 481 } 482 if (rc < 0) 483 return 1; 484 485 /* 486 * Save XIRR for later. Since we get control in reverse endian 487 * on LE systems, save it byte reversed and fetch it back in 488 * host endian. Note that xirr is the value read from the 489 * XIRR register, while h_xirr is the host endian version. 490 */ 491 h_xirr = be32_to_cpu(xirr); 492 local_paca->kvm_hstate.saved_xirr = h_xirr; 493 xisr = h_xirr & 0xffffff; 494 /* 495 * Ensure that the store/load complete to guarantee all side 496 * effects of loading from XIRR has completed 497 */ 498 smp_mb(); 499 500 /* if nothing pending in the ICP */ 501 if (!xisr) 502 return 0; 503 504 /* We found something in the ICP... 505 * 506 * If it is an IPI, clear the MFRR and EOI it. 507 */ 508 if (xisr == XICS_IPI) { 509 rc = 0; 510 if (kvmhv_on_pseries()) { 511 unsigned long retbuf[PLPAR_HCALL_BUFSIZE]; 512 513 plpar_hcall_raw(H_IPI, retbuf, 514 hard_smp_processor_id(), 0xff); 515 plpar_hcall_raw(H_EOI, retbuf, h_xirr); 516 } else if (xics_phys) { 517 __raw_rm_writeb(0xff, xics_phys + XICS_MFRR); 518 __raw_rm_writel(xirr, xics_phys + XICS_XIRR); 519 } else { 520 opal_int_set_mfrr(hard_smp_processor_id(), 0xff); 521 rc = opal_int_eoi(h_xirr); 522 } 523 /* If rc > 0, there is another interrupt pending */ 524 *again = rc > 0; 525 526 /* 527 * Need to ensure side effects of above stores 528 * complete before proceeding. 529 */ 530 smp_mb(); 531 532 /* 533 * We need to re-check host IPI now in case it got set in the 534 * meantime. If it's clear, we bounce the interrupt to the 535 * guest 536 */ 537 host_ipi = local_paca->kvm_hstate.host_ipi; 538 if (unlikely(host_ipi != 0)) { 539 /* We raced with the host, 540 * we need to resend that IPI, bummer 541 */ 542 if (kvmhv_on_pseries()) { 543 unsigned long retbuf[PLPAR_HCALL_BUFSIZE]; 544 545 plpar_hcall_raw(H_IPI, retbuf, 546 hard_smp_processor_id(), 547 IPI_PRIORITY); 548 } else if (xics_phys) 549 __raw_rm_writeb(IPI_PRIORITY, 550 xics_phys + XICS_MFRR); 551 else 552 opal_int_set_mfrr(hard_smp_processor_id(), 553 IPI_PRIORITY); 554 /* Let side effects complete */ 555 smp_mb(); 556 return 1; 557 } 558 559 /* OK, it's an IPI for us */ 560 local_paca->kvm_hstate.saved_xirr = 0; 561 return -1; 562 } 563 564 return kvmppc_check_passthru(xisr, xirr, again); 565 } 566 567 #ifdef CONFIG_KVM_XICS 568 static inline bool is_rm(void) 569 { 570 return !(mfmsr() & MSR_DR); 571 } 572 573 unsigned long kvmppc_rm_h_xirr(struct kvm_vcpu *vcpu) 574 { 575 if (!kvmppc_xics_enabled(vcpu)) 576 return H_TOO_HARD; 577 if (xics_on_xive()) { 578 if (is_rm()) 579 return xive_rm_h_xirr(vcpu); 580 if (unlikely(!__xive_vm_h_xirr)) 581 return H_NOT_AVAILABLE; 582 return __xive_vm_h_xirr(vcpu); 583 } else 584 return xics_rm_h_xirr(vcpu); 585 } 586 587 unsigned long kvmppc_rm_h_xirr_x(struct kvm_vcpu *vcpu) 588 { 589 if (!kvmppc_xics_enabled(vcpu)) 590 return H_TOO_HARD; 591 vcpu->arch.regs.gpr[5] = get_tb(); 592 if (xics_on_xive()) { 593 if (is_rm()) 594 return xive_rm_h_xirr(vcpu); 595 if (unlikely(!__xive_vm_h_xirr)) 596 return H_NOT_AVAILABLE; 597 return __xive_vm_h_xirr(vcpu); 598 } else 599 return xics_rm_h_xirr(vcpu); 600 } 601 602 unsigned long kvmppc_rm_h_ipoll(struct kvm_vcpu *vcpu, unsigned long server) 603 { 604 if (!kvmppc_xics_enabled(vcpu)) 605 return H_TOO_HARD; 606 if (xics_on_xive()) { 607 if (is_rm()) 608 return xive_rm_h_ipoll(vcpu, server); 609 if (unlikely(!__xive_vm_h_ipoll)) 610 return H_NOT_AVAILABLE; 611 return __xive_vm_h_ipoll(vcpu, server); 612 } else 613 return H_TOO_HARD; 614 } 615 616 int kvmppc_rm_h_ipi(struct kvm_vcpu *vcpu, unsigned long server, 617 unsigned long mfrr) 618 { 619 if (!kvmppc_xics_enabled(vcpu)) 620 return H_TOO_HARD; 621 if (xics_on_xive()) { 622 if (is_rm()) 623 return xive_rm_h_ipi(vcpu, server, mfrr); 624 if (unlikely(!__xive_vm_h_ipi)) 625 return H_NOT_AVAILABLE; 626 return __xive_vm_h_ipi(vcpu, server, mfrr); 627 } else 628 return xics_rm_h_ipi(vcpu, server, mfrr); 629 } 630 631 int kvmppc_rm_h_cppr(struct kvm_vcpu *vcpu, unsigned long cppr) 632 { 633 if (!kvmppc_xics_enabled(vcpu)) 634 return H_TOO_HARD; 635 if (xics_on_xive()) { 636 if (is_rm()) 637 return xive_rm_h_cppr(vcpu, cppr); 638 if (unlikely(!__xive_vm_h_cppr)) 639 return H_NOT_AVAILABLE; 640 return __xive_vm_h_cppr(vcpu, cppr); 641 } else 642 return xics_rm_h_cppr(vcpu, cppr); 643 } 644 645 int kvmppc_rm_h_eoi(struct kvm_vcpu *vcpu, unsigned long xirr) 646 { 647 if (!kvmppc_xics_enabled(vcpu)) 648 return H_TOO_HARD; 649 if (xics_on_xive()) { 650 if (is_rm()) 651 return xive_rm_h_eoi(vcpu, xirr); 652 if (unlikely(!__xive_vm_h_eoi)) 653 return H_NOT_AVAILABLE; 654 return __xive_vm_h_eoi(vcpu, xirr); 655 } else 656 return xics_rm_h_eoi(vcpu, xirr); 657 } 658 #endif /* CONFIG_KVM_XICS */ 659 660 void kvmppc_bad_interrupt(struct pt_regs *regs) 661 { 662 /* 663 * 100 could happen at any time, 200 can happen due to invalid real 664 * address access for example (or any time due to a hardware problem). 665 */ 666 if (TRAP(regs) == 0x100) { 667 get_paca()->in_nmi++; 668 system_reset_exception(regs); 669 get_paca()->in_nmi--; 670 } else if (TRAP(regs) == 0x200) { 671 machine_check_exception(regs); 672 } else { 673 die("Bad interrupt in KVM entry/exit code", regs, SIGABRT); 674 } 675 panic("Bad KVM trap"); 676 } 677 678 /* 679 * Functions used to switch LPCR HR and UPRT bits on all threads 680 * when entering and exiting HPT guests on a radix host. 681 */ 682 683 #define PHASE_REALMODE 1 /* in real mode */ 684 #define PHASE_SET_LPCR 2 /* have set LPCR */ 685 #define PHASE_OUT_OF_GUEST 4 /* have finished executing in guest */ 686 #define PHASE_RESET_LPCR 8 /* have reset LPCR to host value */ 687 688 #define ALL(p) (((p) << 24) | ((p) << 16) | ((p) << 8) | (p)) 689 690 static void wait_for_sync(struct kvm_split_mode *sip, int phase) 691 { 692 int thr = local_paca->kvm_hstate.tid; 693 694 sip->lpcr_sync.phase[thr] |= phase; 695 phase = ALL(phase); 696 while ((sip->lpcr_sync.allphases & phase) != phase) { 697 HMT_low(); 698 barrier(); 699 } 700 HMT_medium(); 701 } 702 703 void kvmhv_p9_set_lpcr(struct kvm_split_mode *sip) 704 { 705 unsigned long rb, set; 706 707 /* wait for every other thread to get to real mode */ 708 wait_for_sync(sip, PHASE_REALMODE); 709 710 /* Set LPCR and LPIDR */ 711 mtspr(SPRN_LPCR, sip->lpcr_req); 712 mtspr(SPRN_LPID, sip->lpidr_req); 713 isync(); 714 715 /* Invalidate the TLB on thread 0 */ 716 if (local_paca->kvm_hstate.tid == 0) { 717 sip->do_set = 0; 718 asm volatile("ptesync" : : : "memory"); 719 for (set = 0; set < POWER9_TLB_SETS_RADIX; ++set) { 720 rb = TLBIEL_INVAL_SET_LPID + 721 (set << TLBIEL_INVAL_SET_SHIFT); 722 asm volatile(PPC_TLBIEL(%0, %1, 0, 0, 0) : : 723 "r" (rb), "r" (0)); 724 } 725 asm volatile("ptesync" : : : "memory"); 726 } 727 728 /* indicate that we have done so and wait for others */ 729 wait_for_sync(sip, PHASE_SET_LPCR); 730 /* order read of sip->lpcr_sync.allphases vs. sip->do_set */ 731 smp_rmb(); 732 } 733 734 /* 735 * Called when a thread that has been in the guest needs 736 * to reload the host LPCR value - but only on POWER9 when 737 * running a HPT guest on a radix host. 738 */ 739 void kvmhv_p9_restore_lpcr(struct kvm_split_mode *sip) 740 { 741 /* we're out of the guest... */ 742 wait_for_sync(sip, PHASE_OUT_OF_GUEST); 743 744 mtspr(SPRN_LPID, 0); 745 mtspr(SPRN_LPCR, sip->host_lpcr); 746 isync(); 747 748 if (local_paca->kvm_hstate.tid == 0) { 749 sip->do_restore = 0; 750 smp_wmb(); /* order store of do_restore vs. phase */ 751 } 752 753 wait_for_sync(sip, PHASE_RESET_LPCR); 754 smp_mb(); 755 local_paca->kvm_hstate.kvm_split_mode = NULL; 756 } 757 758 /* 759 * Is there a PRIV_DOORBELL pending for the guest (on POWER9)? 760 * Can we inject a Decrementer or a External interrupt? 761 */ 762 void kvmppc_guest_entry_inject_int(struct kvm_vcpu *vcpu) 763 { 764 int ext; 765 unsigned long vec = 0; 766 unsigned long lpcr; 767 768 /* Insert EXTERNAL bit into LPCR at the MER bit position */ 769 ext = (vcpu->arch.pending_exceptions >> BOOK3S_IRQPRIO_EXTERNAL) & 1; 770 lpcr = mfspr(SPRN_LPCR); 771 lpcr |= ext << LPCR_MER_SH; 772 mtspr(SPRN_LPCR, lpcr); 773 isync(); 774 775 if (vcpu->arch.shregs.msr & MSR_EE) { 776 if (ext) { 777 vec = BOOK3S_INTERRUPT_EXTERNAL; 778 } else { 779 long int dec = mfspr(SPRN_DEC); 780 if (!(lpcr & LPCR_LD)) 781 dec = (int) dec; 782 if (dec < 0) 783 vec = BOOK3S_INTERRUPT_DECREMENTER; 784 } 785 } 786 if (vec) { 787 unsigned long msr, old_msr = vcpu->arch.shregs.msr; 788 789 kvmppc_set_srr0(vcpu, kvmppc_get_pc(vcpu)); 790 kvmppc_set_srr1(vcpu, old_msr); 791 kvmppc_set_pc(vcpu, vec); 792 msr = vcpu->arch.intr_msr; 793 if (MSR_TM_ACTIVE(old_msr)) 794 msr |= MSR_TS_S; 795 vcpu->arch.shregs.msr = msr; 796 } 797 798 if (vcpu->arch.doorbell_request) { 799 mtspr(SPRN_DPDES, 1); 800 vcpu->arch.vcore->dpdes = 1; 801 smp_wmb(); 802 vcpu->arch.doorbell_request = 0; 803 } 804 } 805 806 static void flush_guest_tlb(struct kvm *kvm) 807 { 808 unsigned long rb, set; 809 810 rb = PPC_BIT(52); /* IS = 2 */ 811 if (kvm_is_radix(kvm)) { 812 /* R=1 PRS=1 RIC=2 */ 813 asm volatile(PPC_TLBIEL(%0, %4, %3, %2, %1) 814 : : "r" (rb), "i" (1), "i" (1), "i" (2), 815 "r" (0) : "memory"); 816 for (set = 1; set < kvm->arch.tlb_sets; ++set) { 817 rb += PPC_BIT(51); /* increment set number */ 818 /* R=1 PRS=1 RIC=0 */ 819 asm volatile(PPC_TLBIEL(%0, %4, %3, %2, %1) 820 : : "r" (rb), "i" (1), "i" (1), "i" (0), 821 "r" (0) : "memory"); 822 } 823 } else { 824 for (set = 0; set < kvm->arch.tlb_sets; ++set) { 825 /* R=0 PRS=0 RIC=0 */ 826 asm volatile(PPC_TLBIEL(%0, %4, %3, %2, %1) 827 : : "r" (rb), "i" (0), "i" (0), "i" (0), 828 "r" (0) : "memory"); 829 rb += PPC_BIT(51); /* increment set number */ 830 } 831 } 832 asm volatile("ptesync": : :"memory"); 833 asm volatile(PPC_INVALIDATE_ERAT : : :"memory"); 834 } 835 836 void kvmppc_check_need_tlb_flush(struct kvm *kvm, int pcpu, 837 struct kvm_nested_guest *nested) 838 { 839 cpumask_t *need_tlb_flush; 840 841 /* 842 * On POWER9, individual threads can come in here, but the 843 * TLB is shared between the 4 threads in a core, hence 844 * invalidating on one thread invalidates for all. 845 * Thus we make all 4 threads use the same bit. 846 */ 847 if (cpu_has_feature(CPU_FTR_ARCH_300)) 848 pcpu = cpu_first_thread_sibling(pcpu); 849 850 if (nested) 851 need_tlb_flush = &nested->need_tlb_flush; 852 else 853 need_tlb_flush = &kvm->arch.need_tlb_flush; 854 855 if (cpumask_test_cpu(pcpu, need_tlb_flush)) { 856 flush_guest_tlb(kvm); 857 858 /* Clear the bit after the TLB flush */ 859 cpumask_clear_cpu(pcpu, need_tlb_flush); 860 } 861 } 862 EXPORT_SYMBOL_GPL(kvmppc_check_need_tlb_flush); 863