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1
/*
2
 * TPR optimization for 32-bit Windows guests (XP and Server 2003)
3
 *
4
 * Copyright (C) 2007-2008 Qumranet Technologies
5
 * Copyright (C) 2012      Jan Kiszka, Siemens AG
6
 *
7
 * This work is licensed under the terms of the GNU GPL version 2, or
8
 * (at your option) any later version. See the COPYING file in the
9
 * top-level directory.
10
 */
11
#include "sysemu/sysemu.h"
12
#include "sysemu/cpus.h"
13
#include "sysemu/kvm.h"
14
#include "hw/i386/apic_internal.h"
15
#include "hw/sysbus.h"
16

    
17
#define VAPIC_IO_PORT           0x7e
18

    
19
#define VAPIC_CPU_SHIFT         7
20

    
21
#define ROM_BLOCK_SIZE          512
22
#define ROM_BLOCK_MASK          (~(ROM_BLOCK_SIZE - 1))
23

    
24
typedef enum VAPICMode {
25
    VAPIC_INACTIVE = 0,
26
    VAPIC_ACTIVE   = 1,
27
    VAPIC_STANDBY  = 2,
28
} VAPICMode;
29

    
30
typedef struct VAPICHandlers {
31
    uint32_t set_tpr;
32
    uint32_t set_tpr_eax;
33
    uint32_t get_tpr[8];
34
    uint32_t get_tpr_stack;
35
} QEMU_PACKED VAPICHandlers;
36

    
37
typedef struct GuestROMState {
38
    char signature[8];
39
    uint32_t vaddr;
40
    uint32_t fixup_start;
41
    uint32_t fixup_end;
42
    uint32_t vapic_vaddr;
43
    uint32_t vapic_size;
44
    uint32_t vcpu_shift;
45
    uint32_t real_tpr_addr;
46
    VAPICHandlers up;
47
    VAPICHandlers mp;
48
} QEMU_PACKED GuestROMState;
49

    
50
typedef struct VAPICROMState {
51
    SysBusDevice busdev;
52
    MemoryRegion io;
53
    MemoryRegion rom;
54
    uint32_t state;
55
    uint32_t rom_state_paddr;
56
    uint32_t rom_state_vaddr;
57
    uint32_t vapic_paddr;
58
    uint32_t real_tpr_addr;
59
    GuestROMState rom_state;
60
    size_t rom_size;
61
    bool rom_mapped_writable;
62
} VAPICROMState;
63

    
64
#define TYPE_VAPIC "kvmvapic"
65
#define VAPIC(obj) OBJECT_CHECK(VAPICROMState, (obj), TYPE_VAPIC)
66

    
67
#define TPR_INSTR_ABS_MODRM             0x1
68
#define TPR_INSTR_MATCH_MODRM_REG       0x2
69

    
70
typedef struct TPRInstruction {
71
    uint8_t opcode;
72
    uint8_t modrm_reg;
73
    unsigned int flags;
74
    TPRAccess access;
75
    size_t length;
76
    off_t addr_offset;
77
} TPRInstruction;
78

    
79
/* must be sorted by length, shortest first */
80
static const TPRInstruction tpr_instr[] = {
81
    { /* mov abs to eax */
82
        .opcode = 0xa1,
83
        .access = TPR_ACCESS_READ,
84
        .length = 5,
85
        .addr_offset = 1,
86
    },
87
    { /* mov eax to abs */
88
        .opcode = 0xa3,
89
        .access = TPR_ACCESS_WRITE,
90
        .length = 5,
91
        .addr_offset = 1,
92
    },
93
    { /* mov r32 to r/m32 */
94
        .opcode = 0x89,
95
        .flags = TPR_INSTR_ABS_MODRM,
96
        .access = TPR_ACCESS_WRITE,
97
        .length = 6,
98
        .addr_offset = 2,
99
    },
100
    { /* mov r/m32 to r32 */
101
        .opcode = 0x8b,
102
        .flags = TPR_INSTR_ABS_MODRM,
103
        .access = TPR_ACCESS_READ,
104
        .length = 6,
105
        .addr_offset = 2,
106
    },
107
    { /* push r/m32 */
108
        .opcode = 0xff,
109
        .modrm_reg = 6,
110
        .flags = TPR_INSTR_ABS_MODRM | TPR_INSTR_MATCH_MODRM_REG,
111
        .access = TPR_ACCESS_READ,
112
        .length = 6,
113
        .addr_offset = 2,
114
    },
115
    { /* mov imm32, r/m32 (c7/0) */
116
        .opcode = 0xc7,
117
        .modrm_reg = 0,
118
        .flags = TPR_INSTR_ABS_MODRM | TPR_INSTR_MATCH_MODRM_REG,
119
        .access = TPR_ACCESS_WRITE,
120
        .length = 10,
121
        .addr_offset = 2,
122
    },
123
};
124

    
125
static void read_guest_rom_state(VAPICROMState *s)
126
{
127
    cpu_physical_memory_rw(s->rom_state_paddr, (void *)&s->rom_state,
128
                           sizeof(GuestROMState), 0);
129
}
130

    
131
static void write_guest_rom_state(VAPICROMState *s)
132
{
133
    cpu_physical_memory_rw(s->rom_state_paddr, (void *)&s->rom_state,
134
                           sizeof(GuestROMState), 1);
135
}
136

    
137
static void update_guest_rom_state(VAPICROMState *s)
138
{
139
    read_guest_rom_state(s);
140

    
141
    s->rom_state.real_tpr_addr = cpu_to_le32(s->real_tpr_addr);
142
    s->rom_state.vcpu_shift = cpu_to_le32(VAPIC_CPU_SHIFT);
143

    
144
    write_guest_rom_state(s);
145
}
146

    
147
static int find_real_tpr_addr(VAPICROMState *s, CPUX86State *env)
148
{
149
    CPUState *cs = CPU(x86_env_get_cpu(env));
150
    hwaddr paddr;
151
    target_ulong addr;
152

    
153
    if (s->state == VAPIC_ACTIVE) {
154
        return 0;
155
    }
156
    /*
157
     * If there is no prior TPR access instruction we could analyze (which is
158
     * the case after resume from hibernation), we need to scan the possible
159
     * virtual address space for the APIC mapping.
160
     */
161
    for (addr = 0xfffff000; addr >= 0x80000000; addr -= TARGET_PAGE_SIZE) {
162
        paddr = cpu_get_phys_page_debug(cs, addr);
163
        if (paddr != APIC_DEFAULT_ADDRESS) {
164
            continue;
165
        }
166
        s->real_tpr_addr = addr + 0x80;
167
        update_guest_rom_state(s);
168
        return 0;
169
    }
170
    return -1;
171
}
172

    
173
static uint8_t modrm_reg(uint8_t modrm)
174
{
175
    return (modrm >> 3) & 7;
176
}
177

    
178
static bool is_abs_modrm(uint8_t modrm)
179
{
180
    return (modrm & 0xc7) == 0x05;
181
}
182

    
183
static bool opcode_matches(uint8_t *opcode, const TPRInstruction *instr)
184
{
185
    return opcode[0] == instr->opcode &&
186
        (!(instr->flags & TPR_INSTR_ABS_MODRM) || is_abs_modrm(opcode[1])) &&
187
        (!(instr->flags & TPR_INSTR_MATCH_MODRM_REG) ||
188
         modrm_reg(opcode[1]) == instr->modrm_reg);
189
}
190

    
191
static int evaluate_tpr_instruction(VAPICROMState *s, X86CPU *cpu,
192
                                    target_ulong *pip, TPRAccess access)
193
{
194
    CPUState *cs = CPU(cpu);
195
    const TPRInstruction *instr;
196
    target_ulong ip = *pip;
197
    uint8_t opcode[2];
198
    uint32_t real_tpr_addr;
199
    int i;
200

    
201
    if ((ip & 0xf0000000ULL) != 0x80000000ULL &&
202
        (ip & 0xf0000000ULL) != 0xe0000000ULL) {
203
        return -1;
204
    }
205

    
206
    /*
207
     * Early Windows 2003 SMP initialization contains a
208
     *
209
     *   mov imm32, r/m32
210
     *
211
     * instruction that is patched by TPR optimization. The problem is that
212
     * RSP, used by the patched instruction, is zero, so the guest gets a
213
     * double fault and dies.
214
     */
215
    if (cpu->env.regs[R_ESP] == 0) {
216
        return -1;
217
    }
218

    
219
    if (kvm_enabled() && !kvm_irqchip_in_kernel()) {
220
        /*
221
         * KVM without kernel-based TPR access reporting will pass an IP that
222
         * points after the accessing instruction. So we need to look backward
223
         * to find the reason.
224
         */
225
        for (i = 0; i < ARRAY_SIZE(tpr_instr); i++) {
226
            instr = &tpr_instr[i];
227
            if (instr->access != access) {
228
                continue;
229
            }
230
            if (cpu_memory_rw_debug(cs, ip - instr->length, opcode,
231
                                    sizeof(opcode), 0) < 0) {
232
                return -1;
233
            }
234
            if (opcode_matches(opcode, instr)) {
235
                ip -= instr->length;
236
                goto instruction_ok;
237
            }
238
        }
239
        return -1;
240
    } else {
241
        if (cpu_memory_rw_debug(cs, ip, opcode, sizeof(opcode), 0) < 0) {
242
            return -1;
243
        }
244
        for (i = 0; i < ARRAY_SIZE(tpr_instr); i++) {
245
            instr = &tpr_instr[i];
246
            if (opcode_matches(opcode, instr)) {
247
                goto instruction_ok;
248
            }
249
        }
250
        return -1;
251
    }
252

    
253
instruction_ok:
254
    /*
255
     * Grab the virtual TPR address from the instruction
256
     * and update the cached values.
257
     */
258
    if (cpu_memory_rw_debug(cs, ip + instr->addr_offset,
259
                            (void *)&real_tpr_addr,
260
                            sizeof(real_tpr_addr), 0) < 0) {
261
        return -1;
262
    }
263
    real_tpr_addr = le32_to_cpu(real_tpr_addr);
264
    if ((real_tpr_addr & 0xfff) != 0x80) {
265
        return -1;
266
    }
267
    s->real_tpr_addr = real_tpr_addr;
268
    update_guest_rom_state(s);
269

    
270
    *pip = ip;
271
    return 0;
272
}
273

    
274
static int update_rom_mapping(VAPICROMState *s, CPUX86State *env, target_ulong ip)
275
{
276
    CPUState *cs = CPU(x86_env_get_cpu(env));
277
    hwaddr paddr;
278
    uint32_t rom_state_vaddr;
279
    uint32_t pos, patch, offset;
280

    
281
    /* nothing to do if already activated */
282
    if (s->state == VAPIC_ACTIVE) {
283
        return 0;
284
    }
285

    
286
    /* bail out if ROM init code was not executed (missing ROM?) */
287
    if (s->state == VAPIC_INACTIVE) {
288
        return -1;
289
    }
290

    
291
    /* find out virtual address of the ROM */
292
    rom_state_vaddr = s->rom_state_paddr + (ip & 0xf0000000);
293
    paddr = cpu_get_phys_page_debug(cs, rom_state_vaddr);
294
    if (paddr == -1) {
295
        return -1;
296
    }
297
    paddr += rom_state_vaddr & ~TARGET_PAGE_MASK;
298
    if (paddr != s->rom_state_paddr) {
299
        return -1;
300
    }
301
    read_guest_rom_state(s);
302
    if (memcmp(s->rom_state.signature, "kvm aPiC", 8) != 0) {
303
        return -1;
304
    }
305
    s->rom_state_vaddr = rom_state_vaddr;
306

    
307
    /* fixup addresses in ROM if needed */
308
    if (rom_state_vaddr == le32_to_cpu(s->rom_state.vaddr)) {
309
        return 0;
310
    }
311
    for (pos = le32_to_cpu(s->rom_state.fixup_start);
312
         pos < le32_to_cpu(s->rom_state.fixup_end);
313
         pos += 4) {
314
        cpu_physical_memory_rw(paddr + pos - s->rom_state.vaddr,
315
                               (void *)&offset, sizeof(offset), 0);
316
        offset = le32_to_cpu(offset);
317
        cpu_physical_memory_rw(paddr + offset, (void *)&patch,
318
                               sizeof(patch), 0);
319
        patch = le32_to_cpu(patch);
320
        patch += rom_state_vaddr - le32_to_cpu(s->rom_state.vaddr);
321
        patch = cpu_to_le32(patch);
322
        cpu_physical_memory_rw(paddr + offset, (void *)&patch,
323
                               sizeof(patch), 1);
324
    }
325
    read_guest_rom_state(s);
326
    s->vapic_paddr = paddr + le32_to_cpu(s->rom_state.vapic_vaddr) -
327
        le32_to_cpu(s->rom_state.vaddr);
328

    
329
    return 0;
330
}
331

    
332
/*
333
 * Tries to read the unique processor number from the Kernel Processor Control
334
 * Region (KPCR) of 32-bit Windows XP and Server 2003. Returns -1 if the KPCR
335
 * cannot be accessed or is considered invalid. This also ensures that we are
336
 * not patching the wrong guest.
337
 */
338
static int get_kpcr_number(X86CPU *cpu)
339
{
340
    CPUX86State *env = &cpu->env;
341
    struct kpcr {
342
        uint8_t  fill1[0x1c];
343
        uint32_t self;
344
        uint8_t  fill2[0x31];
345
        uint8_t  number;
346
    } QEMU_PACKED kpcr;
347

    
348
    if (cpu_memory_rw_debug(CPU(cpu), env->segs[R_FS].base,
349
                            (void *)&kpcr, sizeof(kpcr), 0) < 0 ||
350
        kpcr.self != env->segs[R_FS].base) {
351
        return -1;
352
    }
353
    return kpcr.number;
354
}
355

    
356
static int vapic_enable(VAPICROMState *s, X86CPU *cpu)
357
{
358
    int cpu_number = get_kpcr_number(cpu);
359
    hwaddr vapic_paddr;
360
    static const uint8_t enabled = 1;
361

    
362
    if (cpu_number < 0) {
363
        return -1;
364
    }
365
    vapic_paddr = s->vapic_paddr +
366
        (((hwaddr)cpu_number) << VAPIC_CPU_SHIFT);
367
    cpu_physical_memory_rw(vapic_paddr + offsetof(VAPICState, enabled),
368
                           (void *)&enabled, sizeof(enabled), 1);
369
    apic_enable_vapic(cpu->env.apic_state, vapic_paddr);
370

    
371
    s->state = VAPIC_ACTIVE;
372

    
373
    return 0;
374
}
375

    
376
static void patch_byte(X86CPU *cpu, target_ulong addr, uint8_t byte)
377
{
378
    cpu_memory_rw_debug(CPU(cpu), addr, &byte, 1, 1);
379
}
380

    
381
static void patch_call(VAPICROMState *s, X86CPU *cpu, target_ulong ip,
382
                       uint32_t target)
383
{
384
    uint32_t offset;
385

    
386
    offset = cpu_to_le32(target - ip - 5);
387
    patch_byte(cpu, ip, 0xe8); /* call near */
388
    cpu_memory_rw_debug(CPU(cpu), ip + 1, (void *)&offset, sizeof(offset), 1);
389
}
390

    
391
static void patch_instruction(VAPICROMState *s, X86CPU *cpu, target_ulong ip)
392
{
393
    CPUState *cs = CPU(cpu);
394
    CPUX86State *env = &cpu->env;
395
    VAPICHandlers *handlers;
396
    uint8_t opcode[2];
397
    uint32_t imm32;
398
    target_ulong current_pc = 0;
399
    target_ulong current_cs_base = 0;
400
    int current_flags = 0;
401

    
402
    if (smp_cpus == 1) {
403
        handlers = &s->rom_state.up;
404
    } else {
405
        handlers = &s->rom_state.mp;
406
    }
407

    
408
    if (!kvm_enabled()) {
409
        cpu_restore_state(env, env->mem_io_pc);
410
        cpu_get_tb_cpu_state(env, &current_pc, &current_cs_base,
411
                             &current_flags);
412
    }
413

    
414
    pause_all_vcpus();
415

    
416
    cpu_memory_rw_debug(cs, ip, opcode, sizeof(opcode), 0);
417

    
418
    switch (opcode[0]) {
419
    case 0x89: /* mov r32 to r/m32 */
420
        patch_byte(cpu, ip, 0x50 + modrm_reg(opcode[1]));  /* push reg */
421
        patch_call(s, cpu, ip + 1, handlers->set_tpr);
422
        break;
423
    case 0x8b: /* mov r/m32 to r32 */
424
        patch_byte(cpu, ip, 0x90);
425
        patch_call(s, cpu, ip + 1, handlers->get_tpr[modrm_reg(opcode[1])]);
426
        break;
427
    case 0xa1: /* mov abs to eax */
428
        patch_call(s, cpu, ip, handlers->get_tpr[0]);
429
        break;
430
    case 0xa3: /* mov eax to abs */
431
        patch_call(s, cpu, ip, handlers->set_tpr_eax);
432
        break;
433
    case 0xc7: /* mov imm32, r/m32 (c7/0) */
434
        patch_byte(cpu, ip, 0x68);  /* push imm32 */
435
        cpu_memory_rw_debug(cs, ip + 6, (void *)&imm32, sizeof(imm32), 0);
436
        cpu_memory_rw_debug(cs, ip + 1, (void *)&imm32, sizeof(imm32), 1);
437
        patch_call(s, cpu, ip + 5, handlers->set_tpr);
438
        break;
439
    case 0xff: /* push r/m32 */
440
        patch_byte(cpu, ip, 0x50); /* push eax */
441
        patch_call(s, cpu, ip + 1, handlers->get_tpr_stack);
442
        break;
443
    default:
444
        abort();
445
    }
446

    
447
    resume_all_vcpus();
448

    
449
    if (!kvm_enabled()) {
450
        cs->current_tb = NULL;
451
        tb_gen_code(env, current_pc, current_cs_base, current_flags, 1);
452
        cpu_resume_from_signal(env, NULL);
453
    }
454
}
455

    
456
void vapic_report_tpr_access(DeviceState *dev, CPUState *cs, target_ulong ip,
457
                             TPRAccess access)
458
{
459
    VAPICROMState *s = VAPIC(dev);
460
    X86CPU *cpu = X86_CPU(cs);
461
    CPUX86State *env = &cpu->env;
462

    
463
    cpu_synchronize_state(cs);
464

    
465
    if (evaluate_tpr_instruction(s, cpu, &ip, access) < 0) {
466
        if (s->state == VAPIC_ACTIVE) {
467
            vapic_enable(s, cpu);
468
        }
469
        return;
470
    }
471
    if (update_rom_mapping(s, env, ip) < 0) {
472
        return;
473
    }
474
    if (vapic_enable(s, cpu) < 0) {
475
        return;
476
    }
477
    patch_instruction(s, cpu, ip);
478
}
479

    
480
typedef struct VAPICEnableTPRReporting {
481
    DeviceState *apic;
482
    bool enable;
483
} VAPICEnableTPRReporting;
484

    
485
static void vapic_do_enable_tpr_reporting(void *data)
486
{
487
    VAPICEnableTPRReporting *info = data;
488

    
489
    apic_enable_tpr_access_reporting(info->apic, info->enable);
490
}
491

    
492
static void vapic_enable_tpr_reporting(bool enable)
493
{
494
    VAPICEnableTPRReporting info = {
495
        .enable = enable,
496
    };
497
    CPUState *cs;
498
    X86CPU *cpu;
499
    CPUX86State *env;
500

    
501
    CPU_FOREACH(cs) {
502
        cpu = X86_CPU(cs);
503
        env = &cpu->env;
504
        info.apic = env->apic_state;
505
        run_on_cpu(cs, vapic_do_enable_tpr_reporting, &info);
506
    }
507
}
508

    
509
static void vapic_reset(DeviceState *dev)
510
{
511
    VAPICROMState *s = VAPIC(dev);
512

    
513
    if (s->state == VAPIC_ACTIVE) {
514
        s->state = VAPIC_STANDBY;
515
    }
516
    vapic_enable_tpr_reporting(false);
517
}
518

    
519
/*
520
 * Set the IRQ polling hypercalls to the supported variant:
521
 *  - vmcall if using KVM in-kernel irqchip
522
 *  - 32-bit VAPIC port write otherwise
523
 */
524
static int patch_hypercalls(VAPICROMState *s)
525
{
526
    hwaddr rom_paddr = s->rom_state_paddr & ROM_BLOCK_MASK;
527
    static const uint8_t vmcall_pattern[] = { /* vmcall */
528
        0xb8, 0x1, 0, 0, 0, 0xf, 0x1, 0xc1
529
    };
530
    static const uint8_t outl_pattern[] = { /* nop; outl %eax,0x7e */
531
        0xb8, 0x1, 0, 0, 0, 0x90, 0xe7, 0x7e
532
    };
533
    uint8_t alternates[2];
534
    const uint8_t *pattern;
535
    const uint8_t *patch;
536
    int patches = 0;
537
    off_t pos;
538
    uint8_t *rom;
539

    
540
    rom = g_malloc(s->rom_size);
541
    cpu_physical_memory_rw(rom_paddr, rom, s->rom_size, 0);
542

    
543
    for (pos = 0; pos < s->rom_size - sizeof(vmcall_pattern); pos++) {
544
        if (kvm_irqchip_in_kernel()) {
545
            pattern = outl_pattern;
546
            alternates[0] = outl_pattern[7];
547
            alternates[1] = outl_pattern[7];
548
            patch = &vmcall_pattern[5];
549
        } else {
550
            pattern = vmcall_pattern;
551
            alternates[0] = vmcall_pattern[7];
552
            alternates[1] = 0xd9; /* AMD's VMMCALL */
553
            patch = &outl_pattern[5];
554
        }
555
        if (memcmp(rom + pos, pattern, 7) == 0 &&
556
            (rom[pos + 7] == alternates[0] || rom[pos + 7] == alternates[1])) {
557
            cpu_physical_memory_rw(rom_paddr + pos + 5, (uint8_t *)patch,
558
                                   3, 1);
559
            /*
560
             * Don't flush the tb here. Under ordinary conditions, the patched
561
             * calls are miles away from the current IP. Under malicious
562
             * conditions, the guest could trick us to crash.
563
             */
564
        }
565
    }
566

    
567
    g_free(rom);
568

    
569
    if (patches != 0 && patches != 2) {
570
        return -1;
571
    }
572

    
573
    return 0;
574
}
575

    
576
/*
577
 * For TCG mode or the time KVM honors read-only memory regions, we need to
578
 * enable write access to the option ROM so that variables can be updated by
579
 * the guest.
580
 */
581
static int vapic_map_rom_writable(VAPICROMState *s)
582
{
583
    hwaddr rom_paddr = s->rom_state_paddr & ROM_BLOCK_MASK;
584
    MemoryRegionSection section;
585
    MemoryRegion *as;
586
    size_t rom_size;
587
    uint8_t *ram;
588

    
589
    as = sysbus_address_space(&s->busdev);
590

    
591
    if (s->rom_mapped_writable) {
592
        memory_region_del_subregion(as, &s->rom);
593
        memory_region_destroy(&s->rom);
594
    }
595

    
596
    /* grab RAM memory region (region @rom_paddr may still be pc.rom) */
597
    section = memory_region_find(as, 0, 1);
598

    
599
    /* read ROM size from RAM region */
600
    ram = memory_region_get_ram_ptr(section.mr);
601
    rom_size = ram[rom_paddr + 2] * ROM_BLOCK_SIZE;
602
    if (rom_size == 0) {
603
        return -1;
604
    }
605
    s->rom_size = rom_size;
606

    
607
    /* We need to round to avoid creating subpages
608
     * from which we cannot run code. */
609
    rom_size += rom_paddr & ~TARGET_PAGE_MASK;
610
    rom_paddr &= TARGET_PAGE_MASK;
611
    rom_size = TARGET_PAGE_ALIGN(rom_size);
612

    
613
    memory_region_init_alias(&s->rom, OBJECT(s), "kvmvapic-rom", section.mr,
614
                             rom_paddr, rom_size);
615
    memory_region_add_subregion_overlap(as, rom_paddr, &s->rom, 1000);
616
    s->rom_mapped_writable = true;
617
    memory_region_unref(section.mr);
618

    
619
    return 0;
620
}
621

    
622
static int vapic_prepare(VAPICROMState *s)
623
{
624
    if (vapic_map_rom_writable(s) < 0) {
625
        return -1;
626
    }
627

    
628
    if (patch_hypercalls(s) < 0) {
629
        return -1;
630
    }
631

    
632
    vapic_enable_tpr_reporting(true);
633

    
634
    return 0;
635
}
636

    
637
static void vapic_write(void *opaque, hwaddr addr, uint64_t data,
638
                        unsigned int size)
639
{
640
    CPUState *cs = current_cpu;
641
    X86CPU *cpu = X86_CPU(cs);
642
    CPUX86State *env = &cpu->env;
643
    hwaddr rom_paddr;
644
    VAPICROMState *s = opaque;
645

    
646
    cpu_synchronize_state(cs);
647

    
648
    /*
649
     * The VAPIC supports two PIO-based hypercalls, both via port 0x7E.
650
     *  o 16-bit write access:
651
     *    Reports the option ROM initialization to the hypervisor. Written
652
     *    value is the offset of the state structure in the ROM.
653
     *  o 8-bit write access:
654
     *    Reactivates the VAPIC after a guest hibernation, i.e. after the
655
     *    option ROM content has been re-initialized by a guest power cycle.
656
     *  o 32-bit write access:
657
     *    Poll for pending IRQs, considering the current VAPIC state.
658
     */
659
    switch (size) {
660
    case 2:
661
        if (s->state == VAPIC_INACTIVE) {
662
            rom_paddr = (env->segs[R_CS].base + env->eip) & ROM_BLOCK_MASK;
663
            s->rom_state_paddr = rom_paddr + data;
664

    
665
            s->state = VAPIC_STANDBY;
666
        }
667
        if (vapic_prepare(s) < 0) {
668
            s->state = VAPIC_INACTIVE;
669
            break;
670
        }
671
        break;
672
    case 1:
673
        if (kvm_enabled()) {
674
            /*
675
             * Disable triggering instruction in ROM by writing a NOP.
676
             *
677
             * We cannot do this in TCG mode as the reported IP is not
678
             * accurate.
679
             */
680
            pause_all_vcpus();
681
            patch_byte(cpu, env->eip - 2, 0x66);
682
            patch_byte(cpu, env->eip - 1, 0x90);
683
            resume_all_vcpus();
684
        }
685

    
686
        if (s->state == VAPIC_ACTIVE) {
687
            break;
688
        }
689
        if (update_rom_mapping(s, env, env->eip) < 0) {
690
            break;
691
        }
692
        if (find_real_tpr_addr(s, env) < 0) {
693
            break;
694
        }
695
        vapic_enable(s, cpu);
696
        break;
697
    default:
698
    case 4:
699
        if (!kvm_irqchip_in_kernel()) {
700
            apic_poll_irq(env->apic_state);
701
        }
702
        break;
703
    }
704
}
705

    
706
static uint64_t vapic_read(void *opaque, hwaddr addr, unsigned size)
707
{
708
    return 0xffffffff;
709
}
710

    
711
static const MemoryRegionOps vapic_ops = {
712
    .write = vapic_write,
713
    .read = vapic_read,
714
    .endianness = DEVICE_NATIVE_ENDIAN,
715
};
716

    
717
static void vapic_realize(DeviceState *dev, Error **errp)
718
{
719
    SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
720
    VAPICROMState *s = VAPIC(dev);
721

    
722
    memory_region_init_io(&s->io, OBJECT(s), &vapic_ops, s, "kvmvapic", 2);
723
    sysbus_add_io(sbd, VAPIC_IO_PORT, &s->io);
724
    sysbus_init_ioports(sbd, VAPIC_IO_PORT, 2);
725

    
726
    option_rom[nb_option_roms].name = "kvmvapic.bin";
727
    option_rom[nb_option_roms].bootindex = -1;
728
    nb_option_roms++;
729
}
730

    
731
static void do_vapic_enable(void *data)
732
{
733
    VAPICROMState *s = data;
734
    X86CPU *cpu = X86_CPU(first_cpu);
735

    
736
    vapic_enable(s, cpu);
737
}
738

    
739
static int vapic_post_load(void *opaque, int version_id)
740
{
741
    VAPICROMState *s = opaque;
742
    uint8_t *zero;
743

    
744
    /*
745
     * The old implementation of qemu-kvm did not provide the state
746
     * VAPIC_STANDBY. Reconstruct it.
747
     */
748
    if (s->state == VAPIC_INACTIVE && s->rom_state_paddr != 0) {
749
        s->state = VAPIC_STANDBY;
750
    }
751

    
752
    if (s->state != VAPIC_INACTIVE) {
753
        if (vapic_prepare(s) < 0) {
754
            return -1;
755
        }
756
    }
757
    if (s->state == VAPIC_ACTIVE) {
758
        if (smp_cpus == 1) {
759
            run_on_cpu(first_cpu, do_vapic_enable, s);
760
        } else {
761
            zero = g_malloc0(s->rom_state.vapic_size);
762
            cpu_physical_memory_rw(s->vapic_paddr, zero,
763
                                   s->rom_state.vapic_size, 1);
764
            g_free(zero);
765
        }
766
    }
767

    
768
    return 0;
769
}
770

    
771
static const VMStateDescription vmstate_handlers = {
772
    .name = "kvmvapic-handlers",
773
    .version_id = 1,
774
    .minimum_version_id = 1,
775
    .minimum_version_id_old = 1,
776
    .fields = (VMStateField[]) {
777
        VMSTATE_UINT32(set_tpr, VAPICHandlers),
778
        VMSTATE_UINT32(set_tpr_eax, VAPICHandlers),
779
        VMSTATE_UINT32_ARRAY(get_tpr, VAPICHandlers, 8),
780
        VMSTATE_UINT32(get_tpr_stack, VAPICHandlers),
781
        VMSTATE_END_OF_LIST()
782
    }
783
};
784

    
785
static const VMStateDescription vmstate_guest_rom = {
786
    .name = "kvmvapic-guest-rom",
787
    .version_id = 1,
788
    .minimum_version_id = 1,
789
    .minimum_version_id_old = 1,
790
    .fields = (VMStateField[]) {
791
        VMSTATE_UNUSED(8),     /* signature */
792
        VMSTATE_UINT32(vaddr, GuestROMState),
793
        VMSTATE_UINT32(fixup_start, GuestROMState),
794
        VMSTATE_UINT32(fixup_end, GuestROMState),
795
        VMSTATE_UINT32(vapic_vaddr, GuestROMState),
796
        VMSTATE_UINT32(vapic_size, GuestROMState),
797
        VMSTATE_UINT32(vcpu_shift, GuestROMState),
798
        VMSTATE_UINT32(real_tpr_addr, GuestROMState),
799
        VMSTATE_STRUCT(up, GuestROMState, 0, vmstate_handlers, VAPICHandlers),
800
        VMSTATE_STRUCT(mp, GuestROMState, 0, vmstate_handlers, VAPICHandlers),
801
        VMSTATE_END_OF_LIST()
802
    }
803
};
804

    
805
static const VMStateDescription vmstate_vapic = {
806
    .name = "kvm-tpr-opt",      /* compatible with qemu-kvm VAPIC */
807
    .version_id = 1,
808
    .minimum_version_id = 1,
809
    .minimum_version_id_old = 1,
810
    .post_load = vapic_post_load,
811
    .fields = (VMStateField[]) {
812
        VMSTATE_STRUCT(rom_state, VAPICROMState, 0, vmstate_guest_rom,
813
                       GuestROMState),
814
        VMSTATE_UINT32(state, VAPICROMState),
815
        VMSTATE_UINT32(real_tpr_addr, VAPICROMState),
816
        VMSTATE_UINT32(rom_state_vaddr, VAPICROMState),
817
        VMSTATE_UINT32(vapic_paddr, VAPICROMState),
818
        VMSTATE_UINT32(rom_state_paddr, VAPICROMState),
819
        VMSTATE_END_OF_LIST()
820
    }
821
};
822

    
823
static void vapic_class_init(ObjectClass *klass, void *data)
824
{
825
    DeviceClass *dc = DEVICE_CLASS(klass);
826

    
827
    dc->no_user = 1;
828
    dc->reset   = vapic_reset;
829
    dc->vmsd    = &vmstate_vapic;
830
    dc->realize = vapic_realize;
831
}
832

    
833
static const TypeInfo vapic_type = {
834
    .name          = TYPE_VAPIC,
835
    .parent        = TYPE_SYS_BUS_DEVICE,
836
    .instance_size = sizeof(VAPICROMState),
837
    .class_init    = vapic_class_init,
838
};
839

    
840
static void vapic_register(void)
841
{
842
    type_register_static(&vapic_type);
843
}
844

    
845
type_init(vapic_register);