1 #include "kvm/kvm-cpu.h" 2 3 #include "kvm/symbol.h" 4 #include "kvm/util.h" 5 #include "kvm/kvm.h" 6 7 #include <sys/ioctl.h> 8 #include <sys/mman.h> 9 #include <signal.h> 10 #include <stdlib.h> 11 #include <string.h> 12 #include <errno.h> 13 #include <stdio.h> 14 15 extern __thread struct kvm_cpu *current_kvm_cpu; 16 17 void kvm_cpu__enable_singlestep(struct kvm_cpu *vcpu) 18 { 19 struct kvm_guest_debug debug = { 20 .control = KVM_GUESTDBG_ENABLE | KVM_GUESTDBG_SINGLESTEP, 21 }; 22 23 if (ioctl(vcpu->vcpu_fd, KVM_SET_GUEST_DEBUG, &debug) < 0) 24 pr_warning("KVM_SET_GUEST_DEBUG failed"); 25 } 26 27 void kvm_cpu__run(struct kvm_cpu *vcpu) 28 { 29 int err; 30 31 if (!vcpu->is_running) 32 return; 33 34 err = ioctl(vcpu->vcpu_fd, KVM_RUN, 0); 35 if (err < 0 && (errno != EINTR && errno != EAGAIN)) 36 die_perror("KVM_RUN failed"); 37 } 38 39 static void kvm_cpu_signal_handler(int signum) 40 { 41 if (signum == SIGKVMEXIT) { 42 if (current_kvm_cpu && current_kvm_cpu->is_running) { 43 current_kvm_cpu->is_running = false; 44 kvm__continue(current_kvm_cpu->kvm); 45 } 46 } else if (signum == SIGKVMPAUSE) { 47 current_kvm_cpu->paused = 1; 48 } 49 } 50 51 static void kvm_cpu__handle_coalesced_mmio(struct kvm_cpu *cpu) 52 { 53 if (cpu->ring) { 54 while (cpu->ring->first != cpu->ring->last) { 55 struct kvm_coalesced_mmio *m; 56 m = &cpu->ring->coalesced_mmio[cpu->ring->first]; 57 kvm_cpu__emulate_mmio(cpu->kvm, 58 m->phys_addr, 59 m->data, 60 m->len, 61 1); 62 cpu->ring->first = (cpu->ring->first + 1) % KVM_COALESCED_MMIO_MAX; 63 } 64 } 65 } 66 67 void kvm_cpu__reboot(struct kvm *kvm) 68 { 69 int i; 70 71 /* The kvm->cpus array contains a null pointer in the last location */ 72 for (i = 0; ; i++) { 73 if (kvm->cpus[i]) 74 pthread_kill(kvm->cpus[i]->thread, SIGKVMEXIT); 75 else 76 break; 77 } 78 } 79 80 int kvm_cpu__start(struct kvm_cpu *cpu) 81 { 82 sigset_t sigset; 83 84 sigemptyset(&sigset); 85 sigaddset(&sigset, SIGALRM); 86 87 pthread_sigmask(SIG_BLOCK, &sigset, NULL); 88 89 signal(SIGKVMEXIT, kvm_cpu_signal_handler); 90 signal(SIGKVMPAUSE, kvm_cpu_signal_handler); 91 92 kvm_cpu__reset_vcpu(cpu); 93 94 if (cpu->kvm->cfg.single_step) 95 kvm_cpu__enable_singlestep(cpu); 96 97 while (cpu->is_running) { 98 if (cpu->paused) { 99 kvm__notify_paused(); 100 cpu->paused = 0; 101 } 102 103 if (cpu->needs_nmi) { 104 kvm_cpu__arch_nmi(cpu); 105 cpu->needs_nmi = 0; 106 } 107 108 kvm_cpu__run(cpu); 109 110 switch (cpu->kvm_run->exit_reason) { 111 case KVM_EXIT_UNKNOWN: 112 break; 113 case KVM_EXIT_DEBUG: 114 kvm_cpu__show_registers(cpu); 115 kvm_cpu__show_code(cpu); 116 break; 117 case KVM_EXIT_IO: { 118 bool ret; 119 120 ret = kvm_cpu__emulate_io(cpu->kvm, 121 cpu->kvm_run->io.port, 122 (u8 *)cpu->kvm_run + 123 cpu->kvm_run->io.data_offset, 124 cpu->kvm_run->io.direction, 125 cpu->kvm_run->io.size, 126 cpu->kvm_run->io.count); 127 128 if (!ret) 129 goto panic_kvm; 130 break; 131 } 132 case KVM_EXIT_MMIO: { 133 bool ret; 134 135 /* 136 * If we had MMIO exit, coalesced ring should be processed 137 * *before* processing the exit itself 138 */ 139 kvm_cpu__handle_coalesced_mmio(cpu); 140 141 ret = kvm_cpu__emulate_mmio(cpu->kvm, 142 cpu->kvm_run->mmio.phys_addr, 143 cpu->kvm_run->mmio.data, 144 cpu->kvm_run->mmio.len, 145 cpu->kvm_run->mmio.is_write); 146 147 if (!ret) 148 goto panic_kvm; 149 break; 150 } 151 case KVM_EXIT_INTR: 152 if (cpu->is_running) 153 break; 154 goto exit_kvm; 155 case KVM_EXIT_SHUTDOWN: 156 goto exit_kvm; 157 default: { 158 bool ret; 159 160 ret = kvm_cpu__handle_exit(cpu); 161 if (!ret) 162 goto panic_kvm; 163 break; 164 } 165 } 166 kvm_cpu__handle_coalesced_mmio(cpu); 167 } 168 169 exit_kvm: 170 return 0; 171 172 panic_kvm: 173 return 1; 174 } 175 176 int kvm_cpu__init(struct kvm *kvm) 177 { 178 int max_cpus, recommended_cpus, i; 179 180 max_cpus = kvm__max_cpus(kvm); 181 recommended_cpus = kvm__recommended_cpus(kvm); 182 183 if (kvm->cfg.nrcpus > max_cpus) { 184 printf(" # Limit the number of CPUs to %d\n", max_cpus); 185 kvm->cfg.nrcpus = max_cpus; 186 } else if (kvm->cfg.nrcpus > recommended_cpus) { 187 printf(" # Warning: The maximum recommended amount of VCPUs" 188 " is %d\n", recommended_cpus); 189 } 190 191 kvm->nrcpus = kvm->cfg.nrcpus; 192 193 /* Alloc one pointer too many, so array ends up 0-terminated */ 194 kvm->cpus = calloc(kvm->nrcpus + 1, sizeof(void *)); 195 if (!kvm->cpus) { 196 pr_warning("Couldn't allocate array for %d CPUs", kvm->nrcpus); 197 return -ENOMEM; 198 } 199 200 for (i = 0; i < kvm->nrcpus; i++) { 201 kvm->cpus[i] = kvm_cpu__arch_init(kvm, i); 202 if (!kvm->cpus[i]) { 203 pr_warning("unable to initialize KVM VCPU"); 204 goto fail_alloc; 205 } 206 } 207 208 return 0; 209 210 fail_alloc: 211 for (i = 0; i < kvm->nrcpus; i++) 212 free(kvm->cpus[i]); 213 return -ENOMEM; 214 } 215 base_init(kvm_cpu__init); 216 217 int kvm_cpu__exit(struct kvm *kvm) 218 { 219 int i, r; 220 void *ret = NULL; 221 222 kvm_cpu__delete(kvm->cpus[0]); 223 kvm->cpus[0] = NULL; 224 225 for (i = 1; i < kvm->nrcpus; i++) { 226 if (kvm->cpus[i]->is_running) { 227 pthread_kill(kvm->cpus[i]->thread, SIGKVMEXIT); 228 if (pthread_join(kvm->cpus[i]->thread, &ret) != 0) 229 die("pthread_join"); 230 kvm_cpu__delete(kvm->cpus[i]); 231 } 232 if (ret == NULL) 233 r = 0; 234 } 235 236 free(kvm->cpus); 237 238 kvm->nrcpus = 0; 239 240 return r; 241 } 242 late_exit(kvm_cpu__exit); 243