linux/arch/x86/kvm/lapic.c
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   1
   2/*
   3 * Local APIC virtualization
   4 *
   5 * Copyright (C) 2006 Qumranet, Inc.
   6 * Copyright (C) 2007 Novell
   7 * Copyright (C) 2007 Intel
   8 *
   9 * Authors:
  10 *   Dor Laor <dor.laor@qumranet.com>
  11 *   Gregory Haskins <ghaskins@novell.com>
  12 *   Yaozu (Eddie) Dong <eddie.dong@intel.com>
  13 *
  14 * Based on Xen 3.1 code, Copyright (c) 2004, Intel Corporation.
  15 *
  16 * This work is licensed under the terms of the GNU GPL, version 2.  See
  17 * the COPYING file in the top-level directory.
  18 */
  19
  20#include <linux/kvm_host.h>
  21#include <linux/kvm.h>
  22#include <linux/mm.h>
  23#include <linux/highmem.h>
  24#include <linux/smp.h>
  25#include <linux/hrtimer.h>
  26#include <linux/io.h>
  27#include <linux/module.h>
  28#include <asm/processor.h>
  29#include <asm/msr.h>
  30#include <asm/page.h>
  31#include <asm/current.h>
  32#include <asm/apicdef.h>
  33#include <asm/atomic.h>
  34#include <asm/div64.h>
  35#include "irq.h"
  36
  37#define PRId64 "d"
  38#define PRIx64 "llx"
  39#define PRIu64 "u"
  40#define PRIo64 "o"
  41
  42#define APIC_BUS_CYCLE_NS 1
  43
  44/* #define apic_debug(fmt,arg...) printk(KERN_WARNING fmt,##arg) */
  45#define apic_debug(fmt, arg...)
  46
  47#define APIC_LVT_NUM                    6
  48/* 14 is the version for Xeon and Pentium 8.4.8*/
  49#define APIC_VERSION                    (0x14UL | ((APIC_LVT_NUM - 1) << 16))
  50#define LAPIC_MMIO_LENGTH               (1 << 12)
  51/* followed define is not in apicdef.h */
  52#define APIC_SHORT_MASK                 0xc0000
  53#define APIC_DEST_NOSHORT               0x0
  54#define APIC_DEST_MASK                  0x800
  55#define MAX_APIC_VECTOR                 256
  56
  57#define VEC_POS(v) ((v) & (32 - 1))
  58#define REG_POS(v) (((v) >> 5) << 4)
  59
  60static inline u32 apic_get_reg(struct kvm_lapic *apic, int reg_off)
  61{
  62        return *((u32 *) (apic->regs + reg_off));
  63}
  64
  65static inline void apic_set_reg(struct kvm_lapic *apic, int reg_off, u32 val)
  66{
  67        *((u32 *) (apic->regs + reg_off)) = val;
  68}
  69
  70static inline int apic_test_and_set_vector(int vec, void *bitmap)
  71{
  72        return test_and_set_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
  73}
  74
  75static inline int apic_test_and_clear_vector(int vec, void *bitmap)
  76{
  77        return test_and_clear_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
  78}
  79
  80static inline void apic_set_vector(int vec, void *bitmap)
  81{
  82        set_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
  83}
  84
  85static inline void apic_clear_vector(int vec, void *bitmap)
  86{
  87        clear_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
  88}
  89
  90static inline int apic_hw_enabled(struct kvm_lapic *apic)
  91{
  92        return (apic)->vcpu->arch.apic_base & MSR_IA32_APICBASE_ENABLE;
  93}
  94
  95static inline int  apic_sw_enabled(struct kvm_lapic *apic)
  96{
  97        return apic_get_reg(apic, APIC_SPIV) & APIC_SPIV_APIC_ENABLED;
  98}
  99
 100static inline int apic_enabled(struct kvm_lapic *apic)
 101{
 102        return apic_sw_enabled(apic) && apic_hw_enabled(apic);
 103}
 104
 105#define LVT_MASK        \
 106        (APIC_LVT_MASKED | APIC_SEND_PENDING | APIC_VECTOR_MASK)
 107
 108#define LINT_MASK       \
 109        (LVT_MASK | APIC_MODE_MASK | APIC_INPUT_POLARITY | \
 110         APIC_LVT_REMOTE_IRR | APIC_LVT_LEVEL_TRIGGER)
 111
 112static inline int kvm_apic_id(struct kvm_lapic *apic)
 113{
 114        return (apic_get_reg(apic, APIC_ID) >> 24) & 0xff;
 115}
 116
 117static inline int apic_lvt_enabled(struct kvm_lapic *apic, int lvt_type)
 118{
 119        return !(apic_get_reg(apic, lvt_type) & APIC_LVT_MASKED);
 120}
 121
 122static inline int apic_lvt_vector(struct kvm_lapic *apic, int lvt_type)
 123{
 124        return apic_get_reg(apic, lvt_type) & APIC_VECTOR_MASK;
 125}
 126
 127static inline int apic_lvtt_period(struct kvm_lapic *apic)
 128{
 129        return apic_get_reg(apic, APIC_LVTT) & APIC_LVT_TIMER_PERIODIC;
 130}
 131
 132static unsigned int apic_lvt_mask[APIC_LVT_NUM] = {
 133        LVT_MASK | APIC_LVT_TIMER_PERIODIC,     /* LVTT */
 134        LVT_MASK | APIC_MODE_MASK,      /* LVTTHMR */
 135        LVT_MASK | APIC_MODE_MASK,      /* LVTPC */
 136        LINT_MASK, LINT_MASK,   /* LVT0-1 */
 137        LVT_MASK                /* LVTERR */
 138};
 139
 140static int find_highest_vector(void *bitmap)
 141{
 142        u32 *word = bitmap;
 143        int word_offset = MAX_APIC_VECTOR >> 5;
 144
 145        while ((word_offset != 0) && (word[(--word_offset) << 2] == 0))
 146                continue;
 147
 148        if (likely(!word_offset && !word[0]))
 149                return -1;
 150        else
 151                return fls(word[word_offset << 2]) - 1 + (word_offset << 5);
 152}
 153
 154static inline int apic_test_and_set_irr(int vec, struct kvm_lapic *apic)
 155{
 156        return apic_test_and_set_vector(vec, apic->regs + APIC_IRR);
 157}
 158
 159static inline void apic_clear_irr(int vec, struct kvm_lapic *apic)
 160{
 161        apic_clear_vector(vec, apic->regs + APIC_IRR);
 162}
 163
 164static inline int apic_find_highest_irr(struct kvm_lapic *apic)
 165{
 166        int result;
 167
 168        result = find_highest_vector(apic->regs + APIC_IRR);
 169        ASSERT(result == -1 || result >= 16);
 170
 171        return result;
 172}
 173
 174int kvm_lapic_find_highest_irr(struct kvm_vcpu *vcpu)
 175{
 176        struct kvm_lapic *apic = vcpu->arch.apic;
 177        int highest_irr;
 178
 179        if (!apic)
 180                return 0;
 181        highest_irr = apic_find_highest_irr(apic);
 182
 183        return highest_irr;
 184}
 185EXPORT_SYMBOL_GPL(kvm_lapic_find_highest_irr);
 186
 187int kvm_apic_set_irq(struct kvm_vcpu *vcpu, u8 vec, u8 trig)
 188{
 189        struct kvm_lapic *apic = vcpu->arch.apic;
 190
 191        if (!apic_test_and_set_irr(vec, apic)) {
 192                /* a new pending irq is set in IRR */
 193                if (trig)
 194                        apic_set_vector(vec, apic->regs + APIC_TMR);
 195                else
 196                        apic_clear_vector(vec, apic->regs + APIC_TMR);
 197                kvm_vcpu_kick(apic->vcpu);
 198                return 1;
 199        }
 200        return 0;
 201}
 202
 203static inline int apic_find_highest_isr(struct kvm_lapic *apic)
 204{
 205        int result;
 206
 207        result = find_highest_vector(apic->regs + APIC_ISR);
 208        ASSERT(result == -1 || result >= 16);
 209
 210        return result;
 211}
 212
 213static void apic_update_ppr(struct kvm_lapic *apic)
 214{
 215        u32 tpr, isrv, ppr;
 216        int isr;
 217
 218        tpr = apic_get_reg(apic, APIC_TASKPRI);
 219        isr = apic_find_highest_isr(apic);
 220        isrv = (isr != -1) ? isr : 0;
 221
 222        if ((tpr & 0xf0) >= (isrv & 0xf0))
 223                ppr = tpr & 0xff;
 224        else
 225                ppr = isrv & 0xf0;
 226
 227        apic_debug("vlapic %p, ppr 0x%x, isr 0x%x, isrv 0x%x",
 228                   apic, ppr, isr, isrv);
 229
 230        apic_set_reg(apic, APIC_PROCPRI, ppr);
 231}
 232
 233static void apic_set_tpr(struct kvm_lapic *apic, u32 tpr)
 234{
 235        apic_set_reg(apic, APIC_TASKPRI, tpr);
 236        apic_update_ppr(apic);
 237}
 238
 239int kvm_apic_match_physical_addr(struct kvm_lapic *apic, u16 dest)
 240{
 241        return kvm_apic_id(apic) == dest;
 242}
 243
 244int kvm_apic_match_logical_addr(struct kvm_lapic *apic, u8 mda)
 245{
 246        int result = 0;
 247        u8 logical_id;
 248
 249        logical_id = GET_APIC_LOGICAL_ID(apic_get_reg(apic, APIC_LDR));
 250
 251        switch (apic_get_reg(apic, APIC_DFR)) {
 252        case APIC_DFR_FLAT:
 253                if (logical_id & mda)
 254                        result = 1;
 255                break;
 256        case APIC_DFR_CLUSTER:
 257                if (((logical_id >> 4) == (mda >> 0x4))
 258                    && (logical_id & mda & 0xf))
 259                        result = 1;
 260                break;
 261        default:
 262                printk(KERN_WARNING "Bad DFR vcpu %d: %08x\n",
 263                       apic->vcpu->vcpu_id, apic_get_reg(apic, APIC_DFR));
 264                break;
 265        }
 266
 267        return result;
 268}
 269
 270static int apic_match_dest(struct kvm_vcpu *vcpu, struct kvm_lapic *source,
 271                           int short_hand, int dest, int dest_mode)
 272{
 273        int result = 0;
 274        struct kvm_lapic *target = vcpu->arch.apic;
 275
 276        apic_debug("target %p, source %p, dest 0x%x, "
 277                   "dest_mode 0x%x, short_hand 0x%x",
 278                   target, source, dest, dest_mode, short_hand);
 279
 280        ASSERT(!target);
 281        switch (short_hand) {
 282        case APIC_DEST_NOSHORT:
 283                if (dest_mode == 0) {
 284                        /* Physical mode. */
 285                        if ((dest == 0xFF) || (dest == kvm_apic_id(target)))
 286                                result = 1;
 287                } else
 288                        /* Logical mode. */
 289                        result = kvm_apic_match_logical_addr(target, dest);
 290                break;
 291        case APIC_DEST_SELF:
 292                if (target == source)
 293                        result = 1;
 294                break;
 295        case APIC_DEST_ALLINC:
 296                result = 1;
 297                break;
 298        case APIC_DEST_ALLBUT:
 299                if (target != source)
 300                        result = 1;
 301                break;
 302        default:
 303                printk(KERN_WARNING "Bad dest shorthand value %x\n",
 304                       short_hand);
 305                break;
 306        }
 307
 308        return result;
 309}
 310
 311/*
 312 * Add a pending IRQ into lapic.
 313 * Return 1 if successfully added and 0 if discarded.
 314 */
 315static int __apic_accept_irq(struct kvm_lapic *apic, int delivery_mode,
 316                             int vector, int level, int trig_mode)
 317{
 318        int orig_irr, result = 0;
 319        struct kvm_vcpu *vcpu = apic->vcpu;
 320
 321        switch (delivery_mode) {
 322        case APIC_DM_FIXED:
 323        case APIC_DM_LOWEST:
 324                /* FIXME add logic for vcpu on reset */
 325                if (unlikely(!apic_enabled(apic)))
 326                        break;
 327
 328                orig_irr = apic_test_and_set_irr(vector, apic);
 329                if (orig_irr && trig_mode) {
 330                        apic_debug("level trig mode repeatedly for vector %d",
 331                                   vector);
 332                        break;
 333                }
 334
 335                if (trig_mode) {
 336                        apic_debug("level trig mode for vector %d", vector);
 337                        apic_set_vector(vector, apic->regs + APIC_TMR);
 338                } else
 339                        apic_clear_vector(vector, apic->regs + APIC_TMR);
 340
 341                if (vcpu->arch.mp_state == VCPU_MP_STATE_RUNNABLE)
 342                        kvm_vcpu_kick(vcpu);
 343                else if (vcpu->arch.mp_state == VCPU_MP_STATE_HALTED) {
 344                        vcpu->arch.mp_state = VCPU_MP_STATE_RUNNABLE;
 345                        if (waitqueue_active(&vcpu->wq))
 346                                wake_up_interruptible(&vcpu->wq);
 347                }
 348
 349                result = (orig_irr == 0);
 350                break;
 351
 352        case APIC_DM_REMRD:
 353                printk(KERN_DEBUG "Ignoring delivery mode 3\n");
 354                break;
 355
 356        case APIC_DM_SMI:
 357                printk(KERN_DEBUG "Ignoring guest SMI\n");
 358                break;
 359        case APIC_DM_NMI:
 360                printk(KERN_DEBUG "Ignoring guest NMI\n");
 361                break;
 362
 363        case APIC_DM_INIT:
 364                if (level) {
 365                        if (vcpu->arch.mp_state == VCPU_MP_STATE_RUNNABLE)
 366                                printk(KERN_DEBUG
 367                                       "INIT on a runnable vcpu %d\n",
 368                                       vcpu->vcpu_id);
 369                        vcpu->arch.mp_state = VCPU_MP_STATE_INIT_RECEIVED;
 370                        kvm_vcpu_kick(vcpu);
 371                } else {
 372                        printk(KERN_DEBUG
 373                               "Ignoring de-assert INIT to vcpu %d\n",
 374                               vcpu->vcpu_id);
 375                }
 376
 377                break;
 378
 379        case APIC_DM_STARTUP:
 380                printk(KERN_DEBUG "SIPI to vcpu %d vector 0x%02x\n",
 381                       vcpu->vcpu_id, vector);
 382                if (vcpu->arch.mp_state == VCPU_MP_STATE_INIT_RECEIVED) {
 383                        vcpu->arch.sipi_vector = vector;
 384                        vcpu->arch.mp_state = VCPU_MP_STATE_SIPI_RECEIVED;
 385                        if (waitqueue_active(&vcpu->wq))
 386                                wake_up_interruptible(&vcpu->wq);
 387                }
 388                break;
 389
 390        default:
 391                printk(KERN_ERR "TODO: unsupported delivery mode %x\n",
 392                       delivery_mode);
 393                break;
 394        }
 395        return result;
 396}
 397
 398static struct kvm_lapic *kvm_apic_round_robin(struct kvm *kvm, u8 vector,
 399                                       unsigned long bitmap)
 400{
 401        int last;
 402        int next;
 403        struct kvm_lapic *apic = NULL;
 404
 405        last = kvm->arch.round_robin_prev_vcpu;
 406        next = last;
 407
 408        do {
 409                if (++next == KVM_MAX_VCPUS)
 410                        next = 0;
 411                if (kvm->vcpus[next] == NULL || !test_bit(next, &bitmap))
 412                        continue;
 413                apic = kvm->vcpus[next]->arch.apic;
 414                if (apic && apic_enabled(apic))
 415                        break;
 416                apic = NULL;
 417        } while (next != last);
 418        kvm->arch.round_robin_prev_vcpu = next;
 419
 420        if (!apic)
 421                printk(KERN_DEBUG "vcpu not ready for apic_round_robin\n");
 422
 423        return apic;
 424}
 425
 426struct kvm_vcpu *kvm_get_lowest_prio_vcpu(struct kvm *kvm, u8 vector,
 427                unsigned long bitmap)
 428{
 429        struct kvm_lapic *apic;
 430
 431        apic = kvm_apic_round_robin(kvm, vector, bitmap);
 432        if (apic)
 433                return apic->vcpu;
 434        return NULL;
 435}
 436
 437static void apic_set_eoi(struct kvm_lapic *apic)
 438{
 439        int vector = apic_find_highest_isr(apic);
 440
 441        /*
 442         * Not every write EOI will has corresponding ISR,
 443         * one example is when Kernel check timer on setup_IO_APIC
 444         */
 445        if (vector == -1)
 446                return;
 447
 448        apic_clear_vector(vector, apic->regs + APIC_ISR);
 449        apic_update_ppr(apic);
 450
 451        if (apic_test_and_clear_vector(vector, apic->regs + APIC_TMR))
 452                kvm_ioapic_update_eoi(apic->vcpu->kvm, vector);
 453}
 454
 455static void apic_send_ipi(struct kvm_lapic *apic)
 456{
 457        u32 icr_low = apic_get_reg(apic, APIC_ICR);
 458        u32 icr_high = apic_get_reg(apic, APIC_ICR2);
 459
 460        unsigned int dest = GET_APIC_DEST_FIELD(icr_high);
 461        unsigned int short_hand = icr_low & APIC_SHORT_MASK;
 462        unsigned int trig_mode = icr_low & APIC_INT_LEVELTRIG;
 463        unsigned int level = icr_low & APIC_INT_ASSERT;
 464        unsigned int dest_mode = icr_low & APIC_DEST_MASK;
 465        unsigned int delivery_mode = icr_low & APIC_MODE_MASK;
 466        unsigned int vector = icr_low & APIC_VECTOR_MASK;
 467
 468        struct kvm_vcpu *target;
 469        struct kvm_vcpu *vcpu;
 470        unsigned long lpr_map = 0;
 471        int i;
 472
 473        apic_debug("icr_high 0x%x, icr_low 0x%x, "
 474                   "short_hand 0x%x, dest 0x%x, trig_mode 0x%x, level 0x%x, "
 475                   "dest_mode 0x%x, delivery_mode 0x%x, vector 0x%x\n",
 476                   icr_high, icr_low, short_hand, dest,
 477                   trig_mode, level, dest_mode, delivery_mode, vector);
 478
 479        for (i = 0; i < KVM_MAX_VCPUS; i++) {
 480                vcpu = apic->vcpu->kvm->vcpus[i];
 481                if (!vcpu)
 482                        continue;
 483
 484                if (vcpu->arch.apic &&
 485                    apic_match_dest(vcpu, apic, short_hand, dest, dest_mode)) {
 486                        if (delivery_mode == APIC_DM_LOWEST)
 487                                set_bit(vcpu->vcpu_id, &lpr_map);
 488                        else
 489                                __apic_accept_irq(vcpu->arch.apic, delivery_mode,
 490                                                  vector, level, trig_mode);
 491                }
 492        }
 493
 494        if (delivery_mode == APIC_DM_LOWEST) {
 495                target = kvm_get_lowest_prio_vcpu(vcpu->kvm, vector, lpr_map);
 496                if (target != NULL)
 497                        __apic_accept_irq(target->arch.apic, delivery_mode,
 498                                          vector, level, trig_mode);
 499        }
 500}
 501
 502static u32 apic_get_tmcct(struct kvm_lapic *apic)
 503{
 504        u64 counter_passed;
 505        ktime_t passed, now;
 506        u32 tmcct;
 507
 508        ASSERT(apic != NULL);
 509
 510        now = apic->timer.dev.base->get_time();
 511        tmcct = apic_get_reg(apic, APIC_TMICT);
 512
 513        /* if initial count is 0, current count should also be 0 */
 514        if (tmcct == 0)
 515                return 0;
 516
 517        if (unlikely(ktime_to_ns(now) <=
 518                ktime_to_ns(apic->timer.last_update))) {
 519                /* Wrap around */
 520                passed = ktime_add(( {
 521                                    (ktime_t) {
 522                                    .tv64 = KTIME_MAX -
 523                                    (apic->timer.last_update).tv64}; }
 524                                   ), now);
 525                apic_debug("time elapsed\n");
 526        } else
 527                passed = ktime_sub(now, apic->timer.last_update);
 528
 529        counter_passed = div64_64(ktime_to_ns(passed),
 530                                  (APIC_BUS_CYCLE_NS * apic->timer.divide_count));
 531
 532        if (counter_passed > tmcct) {
 533                if (unlikely(!apic_lvtt_period(apic))) {
 534                        /* one-shot timers stick at 0 until reset */
 535                        tmcct = 0;
 536                } else {
 537                        /*
 538                         * periodic timers reset to APIC_TMICT when they
 539                         * hit 0. The while loop simulates this happening N
 540                         * times. (counter_passed %= tmcct) would also work,
 541                         * but might be slower or not work on 32-bit??
 542                         */
 543                        while (counter_passed > tmcct)
 544                                counter_passed -= tmcct;
 545                        tmcct -= counter_passed;
 546                }
 547        } else {
 548                tmcct -= counter_passed;
 549        }
 550
 551        return tmcct;
 552}
 553
 554static void __report_tpr_access(struct kvm_lapic *apic, bool write)
 555{
 556        struct kvm_vcpu *vcpu = apic->vcpu;
 557        struct kvm_run *run = vcpu->run;
 558
 559        set_bit(KVM_REQ_REPORT_TPR_ACCESS, &vcpu->requests);
 560        kvm_x86_ops->cache_regs(vcpu);
 561        run->tpr_access.rip = vcpu->arch.rip;
 562        run->tpr_access.is_write = write;
 563}
 564
 565static inline void report_tpr_access(struct kvm_lapic *apic, bool write)
 566{
 567        if (apic->vcpu->arch.tpr_access_reporting)
 568                __report_tpr_access(apic, write);
 569}
 570
 571static u32 __apic_read(struct kvm_lapic *apic, unsigned int offset)
 572{
 573        u32 val = 0;
 574
 575        if (offset >= LAPIC_MMIO_LENGTH)
 576                return 0;
 577
 578        switch (offset) {
 579        case APIC_ARBPRI:
 580                printk(KERN_WARNING "Access APIC ARBPRI register "
 581                       "which is for P6\n");
 582                break;
 583
 584        case APIC_TMCCT:        /* Timer CCR */
 585                val = apic_get_tmcct(apic);
 586                break;
 587
 588        case APIC_TASKPRI:
 589                report_tpr_access(apic, false);
 590                /* fall thru */
 591        default:
 592                apic_update_ppr(apic);
 593                val = apic_get_reg(apic, offset);
 594                break;
 595        }
 596
 597        return val;
 598}
 599
 600static void apic_mmio_read(struct kvm_io_device *this,
 601                           gpa_t address, int len, void *data)
 602{
 603        struct kvm_lapic *apic = (struct kvm_lapic *)this->private;
 604        unsigned int offset = address - apic->base_address;
 605        unsigned char alignment = offset & 0xf;
 606        u32 result;
 607
 608        if ((alignment + len) > 4) {
 609                printk(KERN_ERR "KVM_APIC_READ: alignment error %lx %d",
 610                       (unsigned long)address, len);
 611                return;
 612        }
 613        result = __apic_read(apic, offset & ~0xf);
 614
 615        switch (len) {
 616        case 1:
 617        case 2:
 618        case 4:
 619                memcpy(data, (char *)&result + alignment, len);
 620                break;
 621        default:
 622                printk(KERN_ERR "Local APIC read with len = %x, "
 623                       "should be 1,2, or 4 instead\n", len);
 624                break;
 625        }
 626}
 627
 628static void update_divide_count(struct kvm_lapic *apic)
 629{
 630        u32 tmp1, tmp2, tdcr;
 631
 632        tdcr = apic_get_reg(apic, APIC_TDCR);
 633        tmp1 = tdcr & 0xf;
 634        tmp2 = ((tmp1 & 0x3) | ((tmp1 & 0x8) >> 1)) + 1;
 635        apic->timer.divide_count = 0x1 << (tmp2 & 0x7);
 636
 637        apic_debug("timer divide count is 0x%x\n",
 638                                   apic->timer.divide_count);
 639}
 640
 641static void start_apic_timer(struct kvm_lapic *apic)
 642{
 643        ktime_t now = apic->timer.dev.base->get_time();
 644
 645        apic->timer.last_update = now;
 646
 647        apic->timer.period = apic_get_reg(apic, APIC_TMICT) *
 648                    APIC_BUS_CYCLE_NS * apic->timer.divide_count;
 649        atomic_set(&apic->timer.pending, 0);
 650
 651        if (!apic->timer.period)
 652                return;
 653
 654        hrtimer_start(&apic->timer.dev,
 655                      ktime_add_ns(now, apic->timer.period),
 656                      HRTIMER_MODE_ABS);
 657
 658        apic_debug("%s: bus cycle is %" PRId64 "ns, now 0x%016"
 659                           PRIx64 ", "
 660                           "timer initial count 0x%x, period %lldns, "
 661                           "expire @ 0x%016" PRIx64 ".\n", __FUNCTION__,
 662                           APIC_BUS_CYCLE_NS, ktime_to_ns(now),
 663                           apic_get_reg(apic, APIC_TMICT),
 664                           apic->timer.period,
 665                           ktime_to_ns(ktime_add_ns(now,
 666                                        apic->timer.period)));
 667}
 668
 669static void apic_mmio_write(struct kvm_io_device *this,
 670                            gpa_t address, int len, const void *data)
 671{
 672        struct kvm_lapic *apic = (struct kvm_lapic *)this->private;
 673        unsigned int offset = address - apic->base_address;
 674        unsigned char alignment = offset & 0xf;
 675        u32 val;
 676
 677        /*
 678         * APIC register must be aligned on 128-bits boundary.
 679         * 32/64/128 bits registers must be accessed thru 32 bits.
 680         * Refer SDM 8.4.1
 681         */
 682        if (len != 4 || alignment) {
 683                if (printk_ratelimit())
 684                        printk(KERN_ERR "apic write: bad size=%d %lx\n",
 685                               len, (long)address);
 686                return;
 687        }
 688
 689        val = *(u32 *) data;
 690
 691        /* too common printing */
 692        if (offset != APIC_EOI)
 693                apic_debug("%s: offset 0x%x with length 0x%x, and value is "
 694                           "0x%x\n", __FUNCTION__, offset, len, val);
 695
 696        offset &= 0xff0;
 697
 698        switch (offset) {
 699        case APIC_ID:           /* Local APIC ID */
 700                apic_set_reg(apic, APIC_ID, val);
 701                break;
 702
 703        case APIC_TASKPRI:
 704                report_tpr_access(apic, true);
 705                apic_set_tpr(apic, val & 0xff);
 706                break;
 707
 708        case APIC_EOI:
 709                apic_set_eoi(apic);
 710                break;
 711
 712        case APIC_LDR:
 713                apic_set_reg(apic, APIC_LDR, val & APIC_LDR_MASK);
 714                break;
 715
 716        case APIC_DFR:
 717                apic_set_reg(apic, APIC_DFR, val | 0x0FFFFFFF);
 718                break;
 719
 720        case APIC_SPIV:
 721                apic_set_reg(apic, APIC_SPIV, val & 0x3ff);
 722                if (!(val & APIC_SPIV_APIC_ENABLED)) {
 723                        int i;
 724                        u32 lvt_val;
 725
 726                        for (i = 0; i < APIC_LVT_NUM; i++) {
 727                                lvt_val = apic_get_reg(apic,
 728                                                       APIC_LVTT + 0x10 * i);
 729                                apic_set_reg(apic, APIC_LVTT + 0x10 * i,
 730                                             lvt_val | APIC_LVT_MASKED);
 731                        }
 732                        atomic_set(&apic->timer.pending, 0);
 733
 734                }
 735                break;
 736
 737        case APIC_ICR:
 738                /* No delay here, so we always clear the pending bit */
 739                apic_set_reg(apic, APIC_ICR, val & ~(1 << 12));
 740                apic_send_ipi(apic);
 741                break;
 742
 743        case APIC_ICR2:
 744                apic_set_reg(apic, APIC_ICR2, val & 0xff000000);
 745                break;
 746
 747        case APIC_LVTT:
 748        case APIC_LVTTHMR:
 749        case APIC_LVTPC:
 750        case APIC_LVT0:
 751        case APIC_LVT1:
 752        case APIC_LVTERR:
 753                /* TODO: Check vector */
 754                if (!apic_sw_enabled(apic))
 755                        val |= APIC_LVT_MASKED;
 756
 757                val &= apic_lvt_mask[(offset - APIC_LVTT) >> 4];
 758                apic_set_reg(apic, offset, val);
 759
 760                break;
 761
 762        case APIC_TMICT:
 763                hrtimer_cancel(&apic->timer.dev);
 764                apic_set_reg(apic, APIC_TMICT, val);
 765                start_apic_timer(apic);
 766                return;
 767
 768        case APIC_TDCR:
 769                if (val & 4)
 770                        printk(KERN_ERR "KVM_WRITE:TDCR %x\n", val);
 771                apic_set_reg(apic, APIC_TDCR, val);
 772                update_divide_count(apic);
 773                break;
 774
 775        default:
 776                apic_debug("Local APIC Write to read-only register %x\n",
 777                           offset);
 778                break;
 779        }
 780
 781}
 782
 783static int apic_mmio_range(struct kvm_io_device *this, gpa_t addr)
 784{
 785        struct kvm_lapic *apic = (struct kvm_lapic *)this->private;
 786        int ret = 0;
 787
 788
 789        if (apic_hw_enabled(apic) &&
 790            (addr >= apic->base_address) &&
 791            (addr < (apic->base_address + LAPIC_MMIO_LENGTH)))
 792                ret = 1;
 793
 794        return ret;
 795}
 796
 797void kvm_free_lapic(struct kvm_vcpu *vcpu)
 798{
 799        if (!vcpu->arch.apic)
 800                return;
 801
 802        hrtimer_cancel(&vcpu->arch.apic->timer.dev);
 803
 804        if (vcpu->arch.apic->regs_page)
 805                __free_page(vcpu->arch.apic->regs_page);
 806
 807        kfree(vcpu->arch.apic);
 808}
 809
 810/*
 811 *----------------------------------------------------------------------
 812 * LAPIC interface
 813 *----------------------------------------------------------------------
 814 */
 815
 816void kvm_lapic_set_tpr(struct kvm_vcpu *vcpu, unsigned long cr8)
 817{
 818        struct kvm_lapic *apic = vcpu->arch.apic;
 819
 820        if (!apic)
 821                return;
 822        apic_set_tpr(apic, ((cr8 & 0x0f) << 4)
 823                     | (apic_get_reg(apic, APIC_TASKPRI) & 4));
 824}
 825
 826u64 kvm_lapic_get_cr8(struct kvm_vcpu *vcpu)
 827{
 828        struct kvm_lapic *apic = vcpu->arch.apic;
 829        u64 tpr;
 830
 831        if (!apic)
 832                return 0;
 833        tpr = (u64) apic_get_reg(apic, APIC_TASKPRI);
 834
 835        return (tpr & 0xf0) >> 4;
 836}
 837EXPORT_SYMBOL_GPL(kvm_lapic_get_cr8);
 838
 839void kvm_lapic_set_base(struct kvm_vcpu *vcpu, u64 value)
 840{
 841        struct kvm_lapic *apic = vcpu->arch.apic;
 842
 843        if (!apic) {
 844                value |= MSR_IA32_APICBASE_BSP;
 845                vcpu->arch.apic_base = value;
 846                return;
 847        }
 848        if (apic->vcpu->vcpu_id)
 849                value &= ~MSR_IA32_APICBASE_BSP;
 850
 851        vcpu->arch.apic_base = value;
 852        apic->base_address = apic->vcpu->arch.apic_base &
 853                             MSR_IA32_APICBASE_BASE;
 854
 855        /* with FSB delivery interrupt, we can restart APIC functionality */
 856        apic_debug("apic base msr is 0x%016" PRIx64 ", and base address is "
 857                   "0x%lx.\n", apic->vcpu->arch.apic_base, apic->base_address);
 858
 859}
 860
 861u64 kvm_lapic_get_base(struct kvm_vcpu *vcpu)
 862{
 863        return vcpu->arch.apic_base;
 864}
 865EXPORT_SYMBOL_GPL(kvm_lapic_get_base);
 866
 867void kvm_lapic_reset(struct kvm_vcpu *vcpu)
 868{
 869        struct kvm_lapic *apic;
 870        int i;
 871
 872        apic_debug("%s\n", __FUNCTION__);
 873
 874        ASSERT(vcpu);
 875        apic = vcpu->arch.apic;
 876        ASSERT(apic != NULL);
 877
 878        /* Stop the timer in case it's a reset to an active apic */
 879        hrtimer_cancel(&apic->timer.dev);
 880
 881        apic_set_reg(apic, APIC_ID, vcpu->vcpu_id << 24);
 882        apic_set_reg(apic, APIC_LVR, APIC_VERSION);
 883
 884        for (i = 0; i < APIC_LVT_NUM; i++)
 885                apic_set_reg(apic, APIC_LVTT + 0x10 * i, APIC_LVT_MASKED);
 886        apic_set_reg(apic, APIC_LVT0,
 887                     SET_APIC_DELIVERY_MODE(0, APIC_MODE_EXTINT));
 888
 889        apic_set_reg(apic, APIC_DFR, 0xffffffffU);
 890        apic_set_reg(apic, APIC_SPIV, 0xff);
 891        apic_set_reg(apic, APIC_TASKPRI, 0);
 892        apic_set_reg(apic, APIC_LDR, 0);
 893        apic_set_reg(apic, APIC_ESR, 0);
 894        apic_set_reg(apic, APIC_ICR, 0);
 895        apic_set_reg(apic, APIC_ICR2, 0);
 896        apic_set_reg(apic, APIC_TDCR, 0);
 897        apic_set_reg(apic, APIC_TMICT, 0);
 898        for (i = 0; i < 8; i++) {
 899                apic_set_reg(apic, APIC_IRR + 0x10 * i, 0);
 900                apic_set_reg(apic, APIC_ISR + 0x10 * i, 0);
 901                apic_set_reg(apic, APIC_TMR + 0x10 * i, 0);
 902        }
 903        update_divide_count(apic);
 904        atomic_set(&apic->timer.pending, 0);
 905        if (vcpu->vcpu_id == 0)
 906                vcpu->arch.apic_base |= MSR_IA32_APICBASE_BSP;
 907        apic_update_ppr(apic);
 908
 909        apic_debug(KERN_INFO "%s: vcpu=%p, id=%d, base_msr="
 910                   "0x%016" PRIx64 ", base_address=0x%0lx.\n", __FUNCTION__,
 911                   vcpu, kvm_apic_id(apic),
 912                   vcpu->arch.apic_base, apic->base_address);
 913}
 914EXPORT_SYMBOL_GPL(kvm_lapic_reset);
 915
 916int kvm_lapic_enabled(struct kvm_vcpu *vcpu)
 917{
 918        struct kvm_lapic *apic = vcpu->arch.apic;
 919        int ret = 0;
 920
 921        if (!apic)
 922                return 0;
 923        ret = apic_enabled(apic);
 924
 925        return ret;
 926}
 927EXPORT_SYMBOL_GPL(kvm_lapic_enabled);
 928
 929/*
 930 *----------------------------------------------------------------------
 931 * timer interface
 932 *----------------------------------------------------------------------
 933 */
 934
 935/* TODO: make sure __apic_timer_fn runs in current pCPU */
 936static int __apic_timer_fn(struct kvm_lapic *apic)
 937{
 938        int result = 0;
 939        wait_queue_head_t *q = &apic->vcpu->wq;
 940
 941        atomic_inc(&apic->timer.pending);
 942        if (waitqueue_active(q)) {
 943                apic->vcpu->arch.mp_state = VCPU_MP_STATE_RUNNABLE;
 944                wake_up_interruptible(q);
 945        }
 946        if (apic_lvtt_period(apic)) {
 947                result = 1;
 948                apic->timer.dev.expires = ktime_add_ns(
 949                                        apic->timer.dev.expires,
 950                                        apic->timer.period);
 951        }
 952        return result;
 953}
 954
 955static int __inject_apic_timer_irq(struct kvm_lapic *apic)
 956{
 957        int vector;
 958
 959        vector = apic_lvt_vector(apic, APIC_LVTT);
 960        return __apic_accept_irq(apic, APIC_DM_FIXED, vector, 1, 0);
 961}
 962
 963static enum hrtimer_restart apic_timer_fn(struct hrtimer *data)
 964{
 965        struct kvm_lapic *apic;
 966        int restart_timer = 0;
 967
 968        apic = container_of(data, struct kvm_lapic, timer.dev);
 969
 970        restart_timer = __apic_timer_fn(apic);
 971
 972        if (restart_timer)
 973                return HRTIMER_RESTART;
 974        else
 975                return HRTIMER_NORESTART;
 976}
 977
 978int kvm_create_lapic(struct kvm_vcpu *vcpu)
 979{
 980        struct kvm_lapic *apic;
 981
 982        ASSERT(vcpu != NULL);
 983        apic_debug("apic_init %d\n", vcpu->vcpu_id);
 984
 985        apic = kzalloc(sizeof(*apic), GFP_KERNEL);
 986        if (!apic)
 987                goto nomem;
 988
 989        vcpu->arch.apic = apic;
 990
 991        apic->regs_page = alloc_page(GFP_KERNEL);
 992        if (apic->regs_page == NULL) {
 993                printk(KERN_ERR "malloc apic regs error for vcpu %x\n",
 994                       vcpu->vcpu_id);
 995                goto nomem_free_apic;
 996        }
 997        apic->regs = page_address(apic->regs_page);
 998        memset(apic->regs, 0, PAGE_SIZE);
 999        apic->vcpu = vcpu;
1000
1001        hrtimer_init(&apic->timer.dev, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
1002        apic->timer.dev.function = apic_timer_fn;
1003        apic->base_address = APIC_DEFAULT_PHYS_BASE;
1004        vcpu->arch.apic_base = APIC_DEFAULT_PHYS_BASE;
1005
1006        kvm_lapic_reset(vcpu);
1007        apic->dev.read = apic_mmio_read;
1008        apic->dev.write = apic_mmio_write;
1009        apic->dev.in_range = apic_mmio_range;
1010        apic->dev.private = apic;
1011
1012        return 0;
1013nomem_free_apic:
1014        kfree(apic);
1015nomem:
1016        return -ENOMEM;
1017}
1018EXPORT_SYMBOL_GPL(kvm_create_lapic);
1019
1020int kvm_apic_has_interrupt(struct kvm_vcpu *vcpu)
1021{
1022        struct kvm_lapic *apic = vcpu->arch.apic;
1023        int highest_irr;
1024
1025        if (!apic || !apic_enabled(apic))
1026                return -1;
1027
1028        apic_update_ppr(apic);
1029        highest_irr = apic_find_highest_irr(apic);
1030        if ((highest_irr == -1) ||
1031            ((highest_irr & 0xF0) <= apic_get_reg(apic, APIC_PROCPRI)))
1032                return -1;
1033        return highest_irr;
1034}
1035
1036int kvm_apic_accept_pic_intr(struct kvm_vcpu *vcpu)
1037{
1038        u32 lvt0 = apic_get_reg(vcpu->arch.apic, APIC_LVT0);
1039        int r = 0;
1040
1041        if (vcpu->vcpu_id == 0) {
1042                if (!apic_hw_enabled(vcpu->arch.apic))
1043                        r = 1;
1044                if ((lvt0 & APIC_LVT_MASKED) == 0 &&
1045                    GET_APIC_DELIVERY_MODE(lvt0) == APIC_MODE_EXTINT)
1046                        r = 1;
1047        }
1048        return r;
1049}
1050
1051void kvm_inject_apic_timer_irqs(struct kvm_vcpu *vcpu)
1052{
1053        struct kvm_lapic *apic = vcpu->arch.apic;
1054
1055        if (apic && apic_lvt_enabled(apic, APIC_LVTT) &&
1056                atomic_read(&apic->timer.pending) > 0) {
1057                if (__inject_apic_timer_irq(apic))
1058                        atomic_dec(&apic->timer.pending);
1059        }
1060}
1061
1062void kvm_apic_timer_intr_post(struct kvm_vcpu *vcpu, int vec)
1063{
1064        struct kvm_lapic *apic = vcpu->arch.apic;
1065
1066        if (apic && apic_lvt_vector(apic, APIC_LVTT) == vec)
1067                apic->timer.last_update = ktime_add_ns(
1068                                apic->timer.last_update,
1069                                apic->timer.period);
1070}
1071
1072int kvm_get_apic_interrupt(struct kvm_vcpu *vcpu)
1073{
1074        int vector = kvm_apic_has_interrupt(vcpu);
1075        struct kvm_lapic *apic = vcpu->arch.apic;
1076
1077        if (vector == -1)
1078                return -1;
1079
1080        apic_set_vector(vector, apic->regs + APIC_ISR);
1081        apic_update_ppr(apic);
1082        apic_clear_irr(vector, apic);
1083        return vector;
1084}
1085
1086void kvm_apic_post_state_restore(struct kvm_vcpu *vcpu)
1087{
1088        struct kvm_lapic *apic = vcpu->arch.apic;
1089
1090        apic->base_address = vcpu->arch.apic_base &
1091                             MSR_IA32_APICBASE_BASE;
1092        apic_set_reg(apic, APIC_LVR, APIC_VERSION);
1093        apic_update_ppr(apic);
1094        hrtimer_cancel(&apic->timer.dev);
1095        update_divide_count(apic);
1096        start_apic_timer(apic);
1097}
1098
1099void __kvm_migrate_apic_timer(struct kvm_vcpu *vcpu)
1100{
1101        struct kvm_lapic *apic = vcpu->arch.apic;
1102        struct hrtimer *timer;
1103
1104        if (!apic)
1105                return;
1106
1107        timer = &apic->timer.dev;
1108        if (hrtimer_cancel(timer))
1109                hrtimer_start(timer, timer->expires, HRTIMER_MODE_ABS);
1110}
1111
1112void kvm_lapic_sync_from_vapic(struct kvm_vcpu *vcpu)
1113{
1114        u32 data;
1115        void *vapic;
1116
1117        if (!irqchip_in_kernel(vcpu->kvm) || !vcpu->arch.apic->vapic_addr)
1118                return;
1119
1120        vapic = kmap_atomic(vcpu->arch.apic->vapic_page, KM_USER0);
1121        data = *(u32 *)(vapic + offset_in_page(vcpu->arch.apic->vapic_addr));
1122        kunmap_atomic(vapic, KM_USER0);
1123
1124        apic_set_tpr(vcpu->arch.apic, data & 0xff);
1125}
1126
1127void kvm_lapic_sync_to_vapic(struct kvm_vcpu *vcpu)
1128{
1129        u32 data, tpr;
1130        int max_irr, max_isr;
1131        struct kvm_lapic *apic;
1132        void *vapic;
1133
1134        if (!irqchip_in_kernel(vcpu->kvm) || !vcpu->arch.apic->vapic_addr)
1135                return;
1136
1137        apic = vcpu->arch.apic;
1138        tpr = apic_get_reg(apic, APIC_TASKPRI) & 0xff;
1139        max_irr = apic_find_highest_irr(apic);
1140        if (max_irr < 0)
1141                max_irr = 0;
1142        max_isr = apic_find_highest_isr(apic);
1143        if (max_isr < 0)
1144                max_isr = 0;
1145        data = (tpr & 0xff) | ((max_isr & 0xf0) << 8) | (max_irr << 24);
1146
1147        vapic = kmap_atomic(vcpu->arch.apic->vapic_page, KM_USER0);
1148        *(u32 *)(vapic + offset_in_page(vcpu->arch.apic->vapic_addr)) = data;
1149        kunmap_atomic(vapic, KM_USER0);
1150}
1151
1152void kvm_lapic_set_vapic_addr(struct kvm_vcpu *vcpu, gpa_t vapic_addr)
1153{
1154        if (!irqchip_in_kernel(vcpu->kvm))
1155                return;
1156
1157        vcpu->arch.apic->vapic_addr = vapic_addr;
1158}
1159
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