arch/x86/kvm/svm/avic.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Kernel-based Virtual Machine driver for Linux
   4  *
   5  * AMD SVM support
   6  *
   7  * Copyright (C) 2006 Qumranet, Inc.
   8  * Copyright 2010 Red Hat, Inc. and/or its affiliates.
   9  *
  10  * Authors:
  11  *   Yaniv Kamay  <yaniv@qumranet.com>
  12  *   Avi Kivity   <avi@qumranet.com>
  13  */
  14
  15 #define pr_fmt(fmt) "SVM: " fmt
  16
  17 #include <linux/kvm_types.h>
  18 #include <linux/hashtable.h>
  19 #include <linux/amd-iommu.h>
  20 #include <linux/kvm_host.h>
  21
  22 #include <asm/irq_remapping.h>
  23
  24 #include "trace.h"
  25 #include "lapic.h"
  26 #include "x86.h"
  27 #include "irq.h"
  28 #include "svm.h"
  29
  30 #define SVM_AVIC_DOORBELL       0xc001011b
  31
  32 #define AVIC_HPA_MASK   ~((0xFFFULL << 52) | 0xFFF)
  33
  34 /*
  35  * 0xff is broadcast, so the max index allowed for physical APIC ID
  36  * table is 0xfe.  APIC IDs above 0xff are reserved.
  37  */
  38 #define AVIC_MAX_PHYSICAL_ID_COUNT      255
  39
  40 #define AVIC_UNACCEL_ACCESS_WRITE_MASK          1
  41 #define AVIC_UNACCEL_ACCESS_OFFSET_MASK         0xFF0
  42 #define AVIC_UNACCEL_ACCESS_VECTOR_MASK         0xFFFFFFFF
  43
  44 /* AVIC GATAG is encoded using VM and VCPU IDs */
  45 #define AVIC_VCPU_ID_BITS               8
  46 #define AVIC_VCPU_ID_MASK               ((1 << AVIC_VCPU_ID_BITS) - 1)
  47
  48 #define AVIC_VM_ID_BITS                 24
  49 #define AVIC_VM_ID_NR                   (1 << AVIC_VM_ID_BITS)
  50 #define AVIC_VM_ID_MASK                 ((1 << AVIC_VM_ID_BITS) - 1)
  51
  52 #define AVIC_GATAG(x, y)                (((x & AVIC_VM_ID_MASK) << AVIC_VCPU_ID_BITS) | \
  53                                                 (y & AVIC_VCPU_ID_MASK))
  54 #define AVIC_GATAG_TO_VMID(x)           ((x >> AVIC_VCPU_ID_BITS) & AVIC_VM_ID_MASK)
  55 #define AVIC_GATAG_TO_VCPUID(x)         (x & AVIC_VCPU_ID_MASK)
  56
  57 /* Note:
  58  * This hash table is used to map VM_ID to a struct kvm_svm,
  59  * when handling AMD IOMMU GALOG notification to schedule in
  60  * a particular vCPU.
  61  */
  62 #define SVM_VM_DATA_HASH_BITS   8
  63 static DEFINE_HASHTABLE(svm_vm_data_hash, SVM_VM_DATA_HASH_BITS);
  64 static u32 next_vm_id = 0;
  65 static bool next_vm_id_wrapped = 0;
  66 static DEFINE_SPINLOCK(svm_vm_data_hash_lock);
  67
  68 /*
  69  * This is a wrapper of struct amd_iommu_ir_data.
  70  */
  71 struct amd_svm_iommu_ir {
  72         struct list_head node;  /* Used by SVM for per-vcpu ir_list */
  73         void *data;             /* Storing pointer to struct amd_ir_data */
  74 };
  75
  76 enum avic_ipi_failure_cause {
  77         AVIC_IPI_FAILURE_INVALID_INT_TYPE,
  78         AVIC_IPI_FAILURE_TARGET_NOT_RUNNING,
  79         AVIC_IPI_FAILURE_INVALID_TARGET,
  80         AVIC_IPI_FAILURE_INVALID_BACKING_PAGE,
  81 };
  82
  83 /* Note:
  84  * This function is called from IOMMU driver to notify
  85  * SVM to schedule in a particular vCPU of a particular VM.
  86  */
  87 int avic_ga_log_notifier(u32 ga_tag)
  88 {
  89         unsigned long flags;
  90         struct kvm_svm *kvm_svm;
  91         struct kvm_vcpu *vcpu = NULL;
  92         u32 vm_id = AVIC_GATAG_TO_VMID(ga_tag);
  93         u32 vcpu_id = AVIC_GATAG_TO_VCPUID(ga_tag);
  94
  95         pr_debug("SVM: %s: vm_id=%#x, vcpu_id=%#x\n", __func__, vm_id, vcpu_id);
  96         trace_kvm_avic_ga_log(vm_id, vcpu_id);
  97
  98         spin_lock_irqsave(&svm_vm_data_hash_lock, flags);
  99         hash_for_each_possible(svm_vm_data_hash, kvm_svm, hnode, vm_id) {
 100                 if (kvm_svm->avic_vm_id != vm_id)
 101                         continue;
 102                 vcpu = kvm_get_vcpu_by_id(&kvm_svm->kvm, vcpu_id);
 103                 break;
 104         }
 105         spin_unlock_irqrestore(&svm_vm_data_hash_lock, flags);
 106
 107         /* Note:
 108          * At this point, the IOMMU should have already set the pending
 109          * bit in the vAPIC backing page. So, we just need to schedule
 110          * in the vcpu.
 111          */
 112         if (vcpu)
 113                 kvm_vcpu_wake_up(vcpu);
 114
 115         return 0;
 116 }
 117
 118 void avic_vm_destroy(struct kvm *kvm)
 119 {
 120         unsigned long flags;
 121         struct kvm_svm *kvm_svm = to_kvm_svm(kvm);
 122
 123         if (!enable_apicv)
 124                 return;
 125
 126         if (kvm_svm->avic_logical_id_table_page)
 127                 __free_page(kvm_svm->avic_logical_id_table_page);
 128         if (kvm_svm->avic_physical_id_table_page)
 129                 __free_page(kvm_svm->avic_physical_id_table_page);
 130
 131         spin_lock_irqsave(&svm_vm_data_hash_lock, flags);
 132         hash_del(&kvm_svm->hnode);
 133         spin_unlock_irqrestore(&svm_vm_data_hash_lock, flags);
 134 }
 135
 136 int avic_vm_init(struct kvm *kvm)
 137 {
 138         unsigned long flags;
 139         int err = -ENOMEM;
 140         struct kvm_svm *kvm_svm = to_kvm_svm(kvm);
 141         struct kvm_svm *k2;
 142         struct page *p_page;
 143         struct page *l_page;
 144         u32 vm_id;
 145
 146         if (!enable_apicv)
 147                 return 0;
 148
 149         /* Allocating physical APIC ID table (4KB) */
 150         p_page = alloc_page(GFP_KERNEL_ACCOUNT | __GFP_ZERO);
 151         if (!p_page)
 152                 goto free_avic;
 153
 154         kvm_svm->avic_physical_id_table_page = p_page;
 155
 156         /* Allocating logical APIC ID table (4KB) */
 157         l_page = alloc_page(GFP_KERNEL_ACCOUNT | __GFP_ZERO);
 158         if (!l_page)
 159                 goto free_avic;
 160
 161         kvm_svm->avic_logical_id_table_page = l_page;
 162
 163         spin_lock_irqsave(&svm_vm_data_hash_lock, flags);
 164  again:
 165         vm_id = next_vm_id = (next_vm_id + 1) & AVIC_VM_ID_MASK;
 166         if (vm_id == 0) { /* id is 1-based, zero is not okay */
 167                 next_vm_id_wrapped = 1;
 168                 goto again;
 169         }
 170         /* Is it still in use? Only possible if wrapped at least once */
 171         if (next_vm_id_wrapped) {
 172                 hash_for_each_possible(svm_vm_data_hash, k2, hnode, vm_id) {
 173                         if (k2->avic_vm_id == vm_id)
 174                                 goto again;
 175                 }
 176         }
 177         kvm_svm->avic_vm_id = vm_id;
 178         hash_add(svm_vm_data_hash, &kvm_svm->hnode, kvm_svm->avic_vm_id);
 179         spin_unlock_irqrestore(&svm_vm_data_hash_lock, flags);
 180
 181         return 0;
 182
 183 free_avic:
 184         avic_vm_destroy(kvm);
 185         return err;
 186 }
 187
 188 void avic_init_vmcb(struct vcpu_svm *svm)
 189 {
 190         struct vmcb *vmcb = svm->vmcb;
 191         struct kvm_svm *kvm_svm = to_kvm_svm(svm->vcpu.kvm);
 192         phys_addr_t bpa = __sme_set(page_to_phys(svm->avic_backing_page));
 193         phys_addr_t lpa = __sme_set(page_to_phys(kvm_svm->avic_logical_id_table_page));
 194         phys_addr_t ppa = __sme_set(page_to_phys(kvm_svm->avic_physical_id_table_page));
 195
 196         vmcb->control.avic_backing_page = bpa & AVIC_HPA_MASK;
 197         vmcb->control.avic_logical_id = lpa & AVIC_HPA_MASK;
 198         vmcb->control.avic_physical_id = ppa & AVIC_HPA_MASK;
 199         vmcb->control.avic_physical_id |= AVIC_MAX_PHYSICAL_ID_COUNT;
 200         vmcb->control.avic_vapic_bar = APIC_DEFAULT_PHYS_BASE & VMCB_AVIC_APIC_BAR_MASK;
 201
 202         if (kvm_apicv_activated(svm->vcpu.kvm))
 203                 vmcb->control.int_ctl |= AVIC_ENABLE_MASK;
 204         else
 205                 vmcb->control.int_ctl &= ~AVIC_ENABLE_MASK;
 206 }
 207
 208 static u64 *avic_get_physical_id_entry(struct kvm_vcpu *vcpu,
 209                                        unsigned int index)
 210 {
 211         u64 *avic_physical_id_table;
 212         struct kvm_svm *kvm_svm = to_kvm_svm(vcpu->kvm);
 213
 214         if (index >= AVIC_MAX_PHYSICAL_ID_COUNT)
 215                 return NULL;
 216
 217         avic_physical_id_table = page_address(kvm_svm->avic_physical_id_table_page);
 218
 219         return &avic_physical_id_table[index];
 220 }
 221
 222 /*
 223  * Note:
 224  * AVIC hardware walks the nested page table to check permissions,
 225  * but does not use the SPA address specified in the leaf page
 226  * table entry since it uses  address in the AVIC_BACKING_PAGE pointer
 227  * field of the VMCB. Therefore, we set up the
 228  * APIC_ACCESS_PAGE_PRIVATE_MEMSLOT (4KB) here.
 229  */
 230 static int avic_alloc_access_page(struct kvm *kvm)
 231 {
 232         void __user *ret;
 233         int r = 0;
 234
 235         mutex_lock(&kvm->slots_lock);
 236
 237         if (kvm->arch.apic_access_memslot_enabled)
 238                 goto out;
 239
 240         ret = __x86_set_memory_region(kvm,
 241                                       APIC_ACCESS_PAGE_PRIVATE_MEMSLOT,
 242                                       APIC_DEFAULT_PHYS_BASE,
 243                                       PAGE_SIZE);
 244         if (IS_ERR(ret)) {
 245                 r = PTR_ERR(ret);
 246                 goto out;
 247         }
 248
 249         kvm->arch.apic_access_memslot_enabled = true;
 250 out:
 251         mutex_unlock(&kvm->slots_lock);
 252         return r;
 253 }
 254
 255 static int avic_init_backing_page(struct kvm_vcpu *vcpu)
 256 {
 257         u64 *entry, new_entry;
 258         int id = vcpu->vcpu_id;
 259         struct vcpu_svm *svm = to_svm(vcpu);
 260
 261         if (id >= AVIC_MAX_PHYSICAL_ID_COUNT)
 262                 return -EINVAL;
 263
 264         if (!vcpu->arch.apic->regs)
 265                 return -EINVAL;
 266
 267         if (kvm_apicv_activated(vcpu->kvm)) {
 268                 int ret;
 269
 270                 ret = avic_alloc_access_page(vcpu->kvm);
 271                 if (ret)
 272                         return ret;
 273         }
 274
 275         svm->avic_backing_page = virt_to_page(vcpu->arch.apic->regs);
 276
 277         /* Setting AVIC backing page address in the phy APIC ID table */
 278         entry = avic_get_physical_id_entry(vcpu, id);
 279         if (!entry)
 280                 return -EINVAL;
 281
 282         new_entry = __sme_set((page_to_phys(svm->avic_backing_page) &
 283                               AVIC_PHYSICAL_ID_ENTRY_BACKING_PAGE_MASK) |
 284                               AVIC_PHYSICAL_ID_ENTRY_VALID_MASK);
 285         WRITE_ONCE(*entry, new_entry);
 286
 287         svm->avic_physical_id_cache = entry;
 288
 289         return 0;
 290 }
 291
 292 static void avic_kick_target_vcpus(struct kvm *kvm, struct kvm_lapic *source,
 293                                    u32 icrl, u32 icrh)
 294 {
 295         struct kvm_vcpu *vcpu;
 296         int i;
 297
 298         kvm_for_each_vcpu(i, vcpu, kvm) {
 299                 bool m = kvm_apic_match_dest(vcpu, source,
 300                                              icrl & APIC_SHORT_MASK,
 301                                              GET_APIC_DEST_FIELD(icrh),
 302                                              icrl & APIC_DEST_MASK);
 303
 304                 if (m && !avic_vcpu_is_running(vcpu))
 305                         kvm_vcpu_wake_up(vcpu);
 306         }
 307 }
 308
 309 int avic_incomplete_ipi_interception(struct kvm_vcpu *vcpu)
 310 {
 311         struct vcpu_svm *svm = to_svm(vcpu);
 312         u32 icrh = svm->vmcb->control.exit_info_1 >> 32;
 313         u32 icrl = svm->vmcb->control.exit_info_1;
 314         u32 id = svm->vmcb->control.exit_info_2 >> 32;
 315         u32 index = svm->vmcb->control.exit_info_2 & 0xFF;
 316         struct kvm_lapic *apic = vcpu->arch.apic;
 317
 318         trace_kvm_avic_incomplete_ipi(vcpu->vcpu_id, icrh, icrl, id, index);
 319
 320         switch (id) {
 321         case AVIC_IPI_FAILURE_INVALID_INT_TYPE:
 322                 /*
 323                  * AVIC hardware handles the generation of
 324                  * IPIs when the specified Message Type is Fixed
 325                  * (also known as fixed delivery mode) and
 326                  * the Trigger Mode is edge-triggered. The hardware
 327                  * also supports self and broadcast delivery modes
 328                  * specified via the Destination Shorthand(DSH)
 329                  * field of the ICRL. Logical and physical APIC ID
 330                  * formats are supported. All other IPI types cause
 331                  * a #VMEXIT, which needs to emulated.
 332                  */
 333                 kvm_lapic_reg_write(apic, APIC_ICR2, icrh);
 334                 kvm_lapic_reg_write(apic, APIC_ICR, icrl);
 335                 break;
 336         case AVIC_IPI_FAILURE_TARGET_NOT_RUNNING:
 337                 /*
 338                  * At this point, we expect that the AVIC HW has already
 339                  * set the appropriate IRR bits on the valid target
 340                  * vcpus. So, we just need to kick the appropriate vcpu.
 341                  */
 342                 avic_kick_target_vcpus(vcpu->kvm, apic, icrl, icrh);
 343                 break;
 344         case AVIC_IPI_FAILURE_INVALID_TARGET:
 345                 WARN_ONCE(1, "Invalid IPI target: index=%u, vcpu=%d, icr=%#0x:%#0x\n",
 346                           index, vcpu->vcpu_id, icrh, icrl);
 347                 break;
 348         case AVIC_IPI_FAILURE_INVALID_BACKING_PAGE:
 349                 WARN_ONCE(1, "Invalid backing page\n");
 350                 break;
 351         default:
 352                 pr_err("Unknown IPI interception\n");
 353         }
 354
 355         return 1;
 356 }
 357
 358 static u32 *avic_get_logical_id_entry(struct kvm_vcpu *vcpu, u32 ldr, bool flat)
 359 {
 360         struct kvm_svm *kvm_svm = to_kvm_svm(vcpu->kvm);
 361         int index;
 362         u32 *logical_apic_id_table;
 363         int dlid = GET_APIC_LOGICAL_ID(ldr);
 364
 365         if (!dlid)
 366                 return NULL;
 367
 368         if (flat) { /* flat */
 369                 index = ffs(dlid) - 1;
 370                 if (index > 7)
 371                         return NULL;
 372         } else { /* cluster */
 373                 int cluster = (dlid & 0xf0) >> 4;
 374                 int apic = ffs(dlid & 0x0f) - 1;
 375
 376                 if ((apic < 0) || (apic > 7) ||
 377                     (cluster >= 0xf))
 378                         return NULL;
 379                 index = (cluster << 2) + apic;
 380         }
 381
 382         logical_apic_id_table = (u32 *) page_address(kvm_svm->avic_logical_id_table_page);
 383
 384         return &logical_apic_id_table[index];
 385 }
 386
 387 static int avic_ldr_write(struct kvm_vcpu *vcpu, u8 g_physical_id, u32 ldr)
 388 {
 389         bool flat;
 390         u32 *entry, new_entry;
 391
 392         flat = kvm_lapic_get_reg(vcpu->arch.apic, APIC_DFR) == APIC_DFR_FLAT;
 393         entry = avic_get_logical_id_entry(vcpu, ldr, flat);
 394         if (!entry)
 395                 return -EINVAL;
 396
 397         new_entry = READ_ONCE(*entry);
 398         new_entry &= ~AVIC_LOGICAL_ID_ENTRY_GUEST_PHYSICAL_ID_MASK;
 399         new_entry |= (g_physical_id & AVIC_LOGICAL_ID_ENTRY_GUEST_PHYSICAL_ID_MASK);
 400         new_entry |= AVIC_LOGICAL_ID_ENTRY_VALID_MASK;
 401         WRITE_ONCE(*entry, new_entry);
 402
 403         return 0;
 404 }
 405
 406 static void avic_invalidate_logical_id_entry(struct kvm_vcpu *vcpu)
 407 {
 408         struct vcpu_svm *svm = to_svm(vcpu);
 409         bool flat = svm->dfr_reg == APIC_DFR_FLAT;
 410         u32 *entry = avic_get_logical_id_entry(vcpu, svm->ldr_reg, flat);
 411
 412         if (entry)
 413                 clear_bit(AVIC_LOGICAL_ID_ENTRY_VALID_BIT, (unsigned long *)entry);
 414 }
 415
 416 static int avic_handle_ldr_update(struct kvm_vcpu *vcpu)
 417 {
 418         int ret = 0;
 419         struct vcpu_svm *svm = to_svm(vcpu);
 420         u32 ldr = kvm_lapic_get_reg(vcpu->arch.apic, APIC_LDR);
 421         u32 id = kvm_xapic_id(vcpu->arch.apic);
 422
 423         if (ldr == svm->ldr_reg)
 424                 return 0;
 425
 426         avic_invalidate_logical_id_entry(vcpu);
 427
 428         if (ldr)
 429                 ret = avic_ldr_write(vcpu, id, ldr);
 430
 431         if (!ret)
 432                 svm->ldr_reg = ldr;
 433
 434         return ret;
 435 }
 436
 437 static int avic_handle_apic_id_update(struct kvm_vcpu *vcpu)
 438 {
 439         u64 *old, *new;
 440         struct vcpu_svm *svm = to_svm(vcpu);
 441         u32 id = kvm_xapic_id(vcpu->arch.apic);
 442
 443         if (vcpu->vcpu_id == id)
 444                 return 0;
 445
 446         old = avic_get_physical_id_entry(vcpu, vcpu->vcpu_id);
 447         new = avic_get_physical_id_entry(vcpu, id);
 448         if (!new || !old)
 449                 return 1;
 450
 451         /* We need to move physical_id_entry to new offset */
 452         *new = *old;
 453         *old = 0ULL;
 454         to_svm(vcpu)->avic_physical_id_cache = new;
 455
 456         /*
 457          * Also update the guest physical APIC ID in the logical
 458          * APIC ID table entry if already setup the LDR.
 459          */
 460         if (svm->ldr_reg)
 461                 avic_handle_ldr_update(vcpu);
 462
 463         return 0;
 464 }
 465
 466 static void avic_handle_dfr_update(struct kvm_vcpu *vcpu)
 467 {
 468         struct vcpu_svm *svm = to_svm(vcpu);
 469         u32 dfr = kvm_lapic_get_reg(vcpu->arch.apic, APIC_DFR);
 470
 471         if (svm->dfr_reg == dfr)
 472                 return;
 473
 474         avic_invalidate_logical_id_entry(vcpu);
 475         svm->dfr_reg = dfr;
 476 }
 477
 478 static int avic_unaccel_trap_write(struct vcpu_svm *svm)
 479 {
 480         struct kvm_lapic *apic = svm->vcpu.arch.apic;
 481         u32 offset = svm->vmcb->control.exit_info_1 &
 482                                 AVIC_UNACCEL_ACCESS_OFFSET_MASK;
 483
 484         switch (offset) {
 485         case APIC_ID:
 486                 if (avic_handle_apic_id_update(&svm->vcpu))
 487                         return 0;
 488                 break;
 489         case APIC_LDR:
 490                 if (avic_handle_ldr_update(&svm->vcpu))
 491                         return 0;
 492                 break;
 493         case APIC_DFR:
 494                 avic_handle_dfr_update(&svm->vcpu);
 495                 break;
 496         default:
 497                 break;
 498         }
 499
 500         kvm_lapic_reg_write(apic, offset, kvm_lapic_get_reg(apic, offset));
 501
 502         return 1;
 503 }
 504
 505 static bool is_avic_unaccelerated_access_trap(u32 offset)
 506 {
 507         bool ret = false;
 508
 509         switch (offset) {
 510         case APIC_ID:
 511         case APIC_EOI:
 512         case APIC_RRR:
 513         case APIC_LDR:
 514         case APIC_DFR:
 515         case APIC_SPIV:
 516         case APIC_ESR:
 517         case APIC_ICR:
 518         case APIC_LVTT:
 519         case APIC_LVTTHMR:
 520         case APIC_LVTPC:
 521         case APIC_LVT0:
 522         case APIC_LVT1:
 523         case APIC_LVTERR:
 524         case APIC_TMICT:
 525         case APIC_TDCR:
 526                 ret = true;
 527                 break;
 528         default:
 529                 break;
 530         }
 531         return ret;
 532 }
 533
 534 int avic_unaccelerated_access_interception(struct kvm_vcpu *vcpu)
 535 {
 536         struct vcpu_svm *svm = to_svm(vcpu);
 537         int ret = 0;
 538         u32 offset = svm->vmcb->control.exit_info_1 &
 539                      AVIC_UNACCEL_ACCESS_OFFSET_MASK;
 540         u32 vector = svm->vmcb->control.exit_info_2 &
 541                      AVIC_UNACCEL_ACCESS_VECTOR_MASK;
 542         bool write = (svm->vmcb->control.exit_info_1 >> 32) &
 543                      AVIC_UNACCEL_ACCESS_WRITE_MASK;
 544         bool trap = is_avic_unaccelerated_access_trap(offset);
 545
 546         trace_kvm_avic_unaccelerated_access(vcpu->vcpu_id, offset,
 547                                             trap, write, vector);
 548         if (trap) {
 549                 /* Handling Trap */
 550                 WARN_ONCE(!write, "svm: Handling trap read.\n");
 551                 ret = avic_unaccel_trap_write(svm);
 552         } else {
 553                 /* Handling Fault */
 554                 ret = kvm_emulate_instruction(vcpu, 0);
 555         }
 556
 557         return ret;
 558 }
 559
 560 int avic_init_vcpu(struct vcpu_svm *svm)
 561 {
 562         int ret;
 563         struct kvm_vcpu *vcpu = &svm->vcpu;
 564
 565         if (!enable_apicv || !irqchip_in_kernel(vcpu->kvm))
 566                 return 0;
 567
 568         ret = avic_init_backing_page(vcpu);
 569         if (ret)
 570                 return ret;
 571
 572         INIT_LIST_HEAD(&svm->ir_list);
 573         spin_lock_init(&svm->ir_list_lock);
 574         svm->dfr_reg = APIC_DFR_FLAT;
 575
 576         return ret;
 577 }
 578
 579 void avic_post_state_restore(struct kvm_vcpu *vcpu)
 580 {
 581         if (avic_handle_apic_id_update(vcpu) != 0)
 582                 return;
 583         avic_handle_dfr_update(vcpu);
 584         avic_handle_ldr_update(vcpu);
 585 }
 586
 587 void svm_set_virtual_apic_mode(struct kvm_vcpu *vcpu)
 588 {
 589         return;
 590 }
 591
 592 void svm_hwapic_irr_update(struct kvm_vcpu *vcpu, int max_irr)
 593 {
 594 }
 595
 596 void svm_hwapic_isr_update(struct kvm_vcpu *vcpu, int max_isr)
 597 {
 598 }
 599
 600 static int svm_set_pi_irte_mode(struct kvm_vcpu *vcpu, bool activate)
 601 {
 602         int ret = 0;
 603         unsigned long flags;
 604         struct amd_svm_iommu_ir *ir;
 605         struct vcpu_svm *svm = to_svm(vcpu);
 606
 607         if (!kvm_arch_has_assigned_device(vcpu->kvm))
 608                 return 0;
 609
 610         /*
 611          * Here, we go through the per-vcpu ir_list to update all existing
 612          * interrupt remapping table entry targeting this vcpu.
 613          */
 614         spin_lock_irqsave(&svm->ir_list_lock, flags);
 615
 616         if (list_empty(&svm->ir_list))
 617                 goto out;
 618
 619         list_for_each_entry(ir, &svm->ir_list, node) {
 620                 if (activate)
 621                         ret = amd_iommu_activate_guest_mode(ir->data);
 622                 else
 623                         ret = amd_iommu_deactivate_guest_mode(ir->data);
 624                 if (ret)
 625                         break;
 626         }
 627 out:
 628         spin_unlock_irqrestore(&svm->ir_list_lock, flags);
 629         return ret;
 630 }
 631
 632 void svm_refresh_apicv_exec_ctrl(struct kvm_vcpu *vcpu)
 633 {
 634         struct vcpu_svm *svm = to_svm(vcpu);
 635         struct vmcb *vmcb = svm->vmcb01.ptr;
 636         bool activated = kvm_vcpu_apicv_active(vcpu);
 637
 638         if (!enable_apicv)
 639                 return;
 640
 641         if (activated) {
 642                 /**
 643                  * During AVIC temporary deactivation, guest could update
 644                  * APIC ID, DFR and LDR registers, which would not be trapped
 645                  * by avic_unaccelerated_access_interception(). In this case,
 646                  * we need to check and update the AVIC logical APIC ID table
 647                  * accordingly before re-activating.
 648                  */
 649                 avic_post_state_restore(vcpu);
 650                 vmcb->control.int_ctl |= AVIC_ENABLE_MASK;
 651         } else {
 652                 vmcb->control.int_ctl &= ~AVIC_ENABLE_MASK;
 653         }
 654         vmcb_mark_dirty(vmcb, VMCB_AVIC);
 655
 656         if (activated)
 657                 avic_vcpu_load(vcpu, vcpu->cpu);
 658         else
 659                 avic_vcpu_put(vcpu);
 660
 661         svm_set_pi_irte_mode(vcpu, activated);
 662 }
 663
 664 void svm_load_eoi_exitmap(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap)
 665 {
 666         return;
 667 }
 668
 669 int svm_deliver_avic_intr(struct kvm_vcpu *vcpu, int vec)
 670 {
 671         if (!vcpu->arch.apicv_active)
 672                 return -1;
 673
 674         kvm_lapic_set_irr(vec, vcpu->arch.apic);
 675         smp_mb__after_atomic();
 676
 677         if (avic_vcpu_is_running(vcpu)) {
 678                 int cpuid = vcpu->cpu;
 679
 680                 if (cpuid != get_cpu())
 681                         wrmsrl(SVM_AVIC_DOORBELL, kvm_cpu_get_apicid(cpuid));
 682                 put_cpu();
 683         } else
 684                 kvm_vcpu_wake_up(vcpu);
 685
 686         return 0;
 687 }
 688
 689 bool svm_dy_apicv_has_pending_interrupt(struct kvm_vcpu *vcpu)
 690 {
 691         return false;
 692 }
 693
 694 static void svm_ir_list_del(struct vcpu_svm *svm, struct amd_iommu_pi_data *pi)
 695 {
 696         unsigned long flags;
 697         struct amd_svm_iommu_ir *cur;
 698
 699         spin_lock_irqsave(&svm->ir_list_lock, flags);
 700         list_for_each_entry(cur, &svm->ir_list, node) {
 701                 if (cur->data != pi->ir_data)
 702                         continue;
 703                 list_del(&cur->node);
 704                 kfree(cur);
 705                 break;
 706         }
 707         spin_unlock_irqrestore(&svm->ir_list_lock, flags);
 708 }
 709
 710 static int svm_ir_list_add(struct vcpu_svm *svm, struct amd_iommu_pi_data *pi)
 711 {
 712         int ret = 0;
 713         unsigned long flags;
 714         struct amd_svm_iommu_ir *ir;
 715
 716         /**
 717          * In some cases, the existing irte is updated and re-set,
 718          * so we need to check here if it's already been * added
 719          * to the ir_list.
 720          */
 721         if (pi->ir_data && (pi->prev_ga_tag != 0)) {
 722                 struct kvm *kvm = svm->vcpu.kvm;
 723                 u32 vcpu_id = AVIC_GATAG_TO_VCPUID(pi->prev_ga_tag);
 724                 struct kvm_vcpu *prev_vcpu = kvm_get_vcpu_by_id(kvm, vcpu_id);
 725                 struct vcpu_svm *prev_svm;
 726
 727                 if (!prev_vcpu) {
 728                         ret = -EINVAL;
 729                         goto out;
 730                 }
 731
 732                 prev_svm = to_svm(prev_vcpu);
 733                 svm_ir_list_del(prev_svm, pi);
 734         }
 735
 736         /**
 737          * Allocating new amd_iommu_pi_data, which will get
 738          * add to the per-vcpu ir_list.
 739          */
 740         ir = kzalloc(sizeof(struct amd_svm_iommu_ir), GFP_KERNEL_ACCOUNT);
 741         if (!ir) {
 742                 ret = -ENOMEM;
 743                 goto out;
 744         }
 745         ir->data = pi->ir_data;
 746
 747         spin_lock_irqsave(&svm->ir_list_lock, flags);
 748         list_add(&ir->node, &svm->ir_list);
 749         spin_unlock_irqrestore(&svm->ir_list_lock, flags);
 750 out:
 751         return ret;
 752 }
 753
 754 /*
 755  * Note:
 756  * The HW cannot support posting multicast/broadcast
 757  * interrupts to a vCPU. So, we still use legacy interrupt
 758  * remapping for these kind of interrupts.
 759  *
 760  * For lowest-priority interrupts, we only support
 761  * those with single CPU as the destination, e.g. user
 762  * configures the interrupts via /proc/irq or uses
 763  * irqbalance to make the interrupts single-CPU.
 764  */
 765 static int
 766 get_pi_vcpu_info(struct kvm *kvm, struct kvm_kernel_irq_routing_entry *e,
 767                  struct vcpu_data *vcpu_info, struct vcpu_svm **svm)
 768 {
 769         struct kvm_lapic_irq irq;
 770         struct kvm_vcpu *vcpu = NULL;
 771
 772         kvm_set_msi_irq(kvm, e, &irq);
 773
 774         if (!kvm_intr_is_single_vcpu(kvm, &irq, &vcpu) ||
 775             !kvm_irq_is_postable(&irq)) {
 776                 pr_debug("SVM: %s: use legacy intr remap mode for irq %u\n",
 777                          __func__, irq.vector);
 778                 return -1;
 779         }
 780
 781         pr_debug("SVM: %s: use GA mode for irq %u\n", __func__,
 782                  irq.vector);
 783         *svm = to_svm(vcpu);
 784         vcpu_info->pi_desc_addr = __sme_set(page_to_phys((*svm)->avic_backing_page));
 785         vcpu_info->vector = irq.vector;
 786
 787         return 0;
 788 }
 789
 790 /*
 791  * svm_update_pi_irte - set IRTE for Posted-Interrupts
 792  *
 793  * @kvm: kvm
 794  * @host_irq: host irq of the interrupt
 795  * @guest_irq: gsi of the interrupt
 796  * @set: set or unset PI
 797  * returns 0 on success, < 0 on failure
 798  */
 799 int svm_update_pi_irte(struct kvm *kvm, unsigned int host_irq,
 800                        uint32_t guest_irq, bool set)
 801 {
 802         struct kvm_kernel_irq_routing_entry *e;
 803         struct kvm_irq_routing_table *irq_rt;
 804         int idx, ret = -EINVAL;
 805
 806         if (!kvm_arch_has_assigned_device(kvm) ||
 807             !irq_remapping_cap(IRQ_POSTING_CAP))
 808                 return 0;
 809
 810         pr_debug("SVM: %s: host_irq=%#x, guest_irq=%#x, set=%#x\n",
 811                  __func__, host_irq, guest_irq, set);
 812
 813         idx = srcu_read_lock(&kvm->irq_srcu);
 814         irq_rt = srcu_dereference(kvm->irq_routing, &kvm->irq_srcu);
 815         WARN_ON(guest_irq >= irq_rt->nr_rt_entries);
 816
 817         hlist_for_each_entry(e, &irq_rt->map[guest_irq], link) {
 818                 struct vcpu_data vcpu_info;
 819                 struct vcpu_svm *svm = NULL;
 820
 821                 if (e->type != KVM_IRQ_ROUTING_MSI)
 822                         continue;
 823
 824                 /**
 825                  * Here, we setup with legacy mode in the following cases:
 826                  * 1. When cannot target interrupt to a specific vcpu.
 827                  * 2. Unsetting posted interrupt.
 828                  * 3. APIC virtualization is disabled for the vcpu.
 829                  * 4. IRQ has incompatible delivery mode (SMI, INIT, etc)
 830                  */
 831                 if (!get_pi_vcpu_info(kvm, e, &vcpu_info, &svm) && set &&
 832                     kvm_vcpu_apicv_active(&svm->vcpu)) {
 833                         struct amd_iommu_pi_data pi;
 834
 835                         /* Try to enable guest_mode in IRTE */
 836                         pi.base = __sme_set(page_to_phys(svm->avic_backing_page) &
 837                                             AVIC_HPA_MASK);
 838                         pi.ga_tag = AVIC_GATAG(to_kvm_svm(kvm)->avic_vm_id,
 839                                                      svm->vcpu.vcpu_id);
 840                         pi.is_guest_mode = true;
 841                         pi.vcpu_data = &vcpu_info;
 842                         ret = irq_set_vcpu_affinity(host_irq, &pi);
 843
 844                         /**
 845                          * Here, we successfully setting up vcpu affinity in
 846                          * IOMMU guest mode. Now, we need to store the posted
 847                          * interrupt information in a per-vcpu ir_list so that
 848                          * we can reference to them directly when we update vcpu
 849                          * scheduling information in IOMMU irte.
 850                          */
 851                         if (!ret && pi.is_guest_mode)
 852                                 svm_ir_list_add(svm, &pi);
 853                 } else {
 854                         /* Use legacy mode in IRTE */
 855                         struct amd_iommu_pi_data pi;
 856
 857                         /**
 858                          * Here, pi is used to:
 859                          * - Tell IOMMU to use legacy mode for this interrupt.
 860                          * - Retrieve ga_tag of prior interrupt remapping data.
 861                          */
 862                         pi.prev_ga_tag = 0;
 863                         pi.is_guest_mode = false;
 864                         ret = irq_set_vcpu_affinity(host_irq, &pi);
 865
 866                         /**
 867                          * Check if the posted interrupt was previously
 868                          * setup with the guest_mode by checking if the ga_tag
 869                          * was cached. If so, we need to clean up the per-vcpu
 870                          * ir_list.
 871                          */
 872                         if (!ret && pi.prev_ga_tag) {
 873                                 int id = AVIC_GATAG_TO_VCPUID(pi.prev_ga_tag);
 874                                 struct kvm_vcpu *vcpu;
 875
 876                                 vcpu = kvm_get_vcpu_by_id(kvm, id);
 877                                 if (vcpu)
 878                                         svm_ir_list_del(to_svm(vcpu), &pi);
 879                         }
 880                 }
 881
 882                 if (!ret && svm) {
 883                         trace_kvm_pi_irte_update(host_irq, svm->vcpu.vcpu_id,
 884                                                  e->gsi, vcpu_info.vector,
 885                                                  vcpu_info.pi_desc_addr, set);
 886                 }
 887
 888                 if (ret < 0) {
 889                         pr_err("%s: failed to update PI IRTE\n", __func__);
 890                         goto out;
 891                 }
 892         }
 893
 894         ret = 0;
 895 out:
 896         srcu_read_unlock(&kvm->irq_srcu, idx);
 897         return ret;
 898 }
 899
 900 bool svm_check_apicv_inhibit_reasons(ulong bit)
 901 {
 902         ulong supported = BIT(APICV_INHIBIT_REASON_DISABLE) |
 903                           BIT(APICV_INHIBIT_REASON_HYPERV) |
 904                           BIT(APICV_INHIBIT_REASON_NESTED) |
 905                           BIT(APICV_INHIBIT_REASON_IRQWIN) |
 906                           BIT(APICV_INHIBIT_REASON_PIT_REINJ) |
 907                           BIT(APICV_INHIBIT_REASON_X2APIC);
 908
 909         return supported & BIT(bit);
 910 }
 911
 912
 913 static inline int
 914 avic_update_iommu_vcpu_affinity(struct kvm_vcpu *vcpu, int cpu, bool r)
 915 {
 916         int ret = 0;
 917         unsigned long flags;
 918         struct amd_svm_iommu_ir *ir;
 919         struct vcpu_svm *svm = to_svm(vcpu);
 920
 921         if (!kvm_arch_has_assigned_device(vcpu->kvm))
 922                 return 0;
 923
 924         /*
 925          * Here, we go through the per-vcpu ir_list to update all existing
 926          * interrupt remapping table entry targeting this vcpu.
 927          */
 928         spin_lock_irqsave(&svm->ir_list_lock, flags);
 929
 930         if (list_empty(&svm->ir_list))
 931                 goto out;
 932
 933         list_for_each_entry(ir, &svm->ir_list, node) {
 934                 ret = amd_iommu_update_ga(cpu, r, ir->data);
 935                 if (ret)
 936                         break;
 937         }
 938 out:
 939         spin_unlock_irqrestore(&svm->ir_list_lock, flags);
 940         return ret;
 941 }
 942
 943 void avic_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
 944 {
 945         u64 entry;
 946         /* ID = 0xff (broadcast), ID > 0xff (reserved) */
 947         int h_physical_id = kvm_cpu_get_apicid(cpu);
 948         struct vcpu_svm *svm = to_svm(vcpu);
 949
 950         /*
 951          * Since the host physical APIC id is 8 bits,
 952          * we can support host APIC ID upto 255.
 953          */
 954         if (WARN_ON(h_physical_id > AVIC_PHYSICAL_ID_ENTRY_HOST_PHYSICAL_ID_MASK))
 955                 return;
 956
 957         entry = READ_ONCE(*(svm->avic_physical_id_cache));
 958         WARN_ON(entry & AVIC_PHYSICAL_ID_ENTRY_IS_RUNNING_MASK);
 959
 960         entry &= ~AVIC_PHYSICAL_ID_ENTRY_HOST_PHYSICAL_ID_MASK;
 961         entry |= (h_physical_id & AVIC_PHYSICAL_ID_ENTRY_HOST_PHYSICAL_ID_MASK);
 962
 963         entry &= ~AVIC_PHYSICAL_ID_ENTRY_IS_RUNNING_MASK;
 964         if (svm->avic_is_running)
 965                 entry |= AVIC_PHYSICAL_ID_ENTRY_IS_RUNNING_MASK;
 966
 967         WRITE_ONCE(*(svm->avic_physical_id_cache), entry);
 968         avic_update_iommu_vcpu_affinity(vcpu, h_physical_id,
 969                                         svm->avic_is_running);
 970 }
 971
 972 void avic_vcpu_put(struct kvm_vcpu *vcpu)
 973 {
 974         u64 entry;
 975         struct vcpu_svm *svm = to_svm(vcpu);
 976
 977         entry = READ_ONCE(*(svm->avic_physical_id_cache));
 978         if (entry & AVIC_PHYSICAL_ID_ENTRY_IS_RUNNING_MASK)
 979                 avic_update_iommu_vcpu_affinity(vcpu, -1, 0);
 980
 981         entry &= ~AVIC_PHYSICAL_ID_ENTRY_IS_RUNNING_MASK;
 982         WRITE_ONCE(*(svm->avic_physical_id_cache), entry);
 983 }
 984
 985 /*
 986  * This function is called during VCPU halt/unhalt.
 987  */
 988 static void avic_set_running(struct kvm_vcpu *vcpu, bool is_run)
 989 {
 990         struct vcpu_svm *svm = to_svm(vcpu);
 991
 992         svm->avic_is_running = is_run;
 993
 994         if (!kvm_vcpu_apicv_active(vcpu))
 995                 return;
 996
 997         if (is_run)
 998                 avic_vcpu_load(vcpu, vcpu->cpu);
 999         else
1000                 avic_vcpu_put(vcpu);
1001 }
1002
1003 void svm_vcpu_blocking(struct kvm_vcpu *vcpu)
1004 {
1005         avic_set_running(vcpu, false);
1006 }
1007
1008 void svm_vcpu_unblocking(struct kvm_vcpu *vcpu)
1009 {
1010         if (kvm_check_request(KVM_REQ_APICV_UPDATE, vcpu))
1011                 kvm_vcpu_update_apicv(vcpu);
1012         avic_set_running(vcpu, true);
1013 }