kvm-all.c

   1 /*
   2  * QEMU KVM support
   3  *
   4  * Copyright IBM, Corp. 2008
   5  *
   6  * Authors:
   7  *  Anthony Liguori   <aliguori@us.ibm.com>
   8  *
   9  * This work is licensed under the terms of the GNU GPL, version 2 or later.
  10  * See the COPYING file in the top-level directory.
  11  *
  12  */
  13
  14 #include <sys/types.h>
  15 #include <sys/ioctl.h>
  16 #include <sys/mman.h>
  17 #include <stdarg.h>
  18
  19 #include <linux/kvm.h>
  20
  21 #include "qemu-common.h"
  22 #include "sysemu.h"
  23 #include "kvm.h"
  24
  25 //#define DEBUG_KVM
  26
  27 #ifdef DEBUG_KVM
  28 #define dprintf(fmt, ...) \
  29     do { fprintf(stderr, fmt, ## __VA_ARGS__); } while (0)
  30 #else
  31 #define dprintf(fmt, ...) \
  32     do { } while (0)
  33 #endif
  34
  35 typedef struct kvm_userspace_memory_region KVMSlot;
  36
  37 int kvm_allowed = 0;
  38
  39 struct KVMState
  40 {
  41     KVMSlot slots[32];
  42     int fd;
  43     int vmfd;
  44 };
  45
  46 static KVMState *kvm_state;
  47
  48 static KVMSlot *kvm_alloc_slot(KVMState *s)
  49 {
  50     int i;
  51
  52     for (i = 0; i < ARRAY_SIZE(s->slots); i++) {
  53         if (s->slots[i].memory_size == 0)
  54             return &s->slots[i];
  55     }
  56
  57     return NULL;
  58 }
  59
  60 static KVMSlot *kvm_lookup_slot(KVMState *s, target_phys_addr_t start_addr)
  61 {
  62     int i;
  63
  64     for (i = 0; i < ARRAY_SIZE(s->slots); i++) {
  65         KVMSlot *mem = &s->slots[i];
  66
  67         if (start_addr >= mem->guest_phys_addr &&
  68             start_addr < (mem->guest_phys_addr + mem->memory_size))
  69             return mem;
  70     }
  71
  72     return NULL;
  73 }
  74
  75 int kvm_init_vcpu(CPUState *env)
  76 {
  77     KVMState *s = kvm_state;
  78     long mmap_size;
  79     int ret;
  80
  81     dprintf("kvm_init_vcpu\n");
  82
  83     ret = kvm_vm_ioctl(s, KVM_CREATE_VCPU, env->cpu_index);
  84     if (ret < 0) {
  85         dprintf("kvm_create_vcpu failed\n");
  86         goto err;
  87     }
  88
  89     env->kvm_fd = ret;
  90     env->kvm_state = s;
  91
  92     mmap_size = kvm_ioctl(s, KVM_GET_VCPU_MMAP_SIZE, 0);
  93     if (mmap_size < 0) {
  94         dprintf("KVM_GET_VCPU_MMAP_SIZE failed\n");
  95         goto err;
  96     }
  97
  98     env->kvm_run = mmap(NULL, mmap_size, PROT_READ | PROT_WRITE, MAP_SHARED,
  99                         env->kvm_fd, 0);
 100     if (env->kvm_run == MAP_FAILED) {
 101         ret = -errno;
 102         dprintf("mmap'ing vcpu state failed\n");
 103         goto err;
 104     }
 105
 106     ret = kvm_arch_init_vcpu(env);
 107
 108 err:
 109     return ret;
 110 }
 111
 112 int kvm_init(int smp_cpus)
 113 {
 114     KVMState *s;
 115     int ret;
 116     int i;
 117
 118     if (smp_cpus > 1)
 119         return -EINVAL;
 120
 121     s = qemu_mallocz(sizeof(KVMState));
 122     if (s == NULL)
 123         return -ENOMEM;
 124
 125     for (i = 0; i < ARRAY_SIZE(s->slots); i++)
 126         s->slots[i].slot = i;
 127
 128     s->vmfd = -1;
 129     s->fd = open("/dev/kvm", O_RDWR);
 130     if (s->fd == -1) {
 131         fprintf(stderr, "Could not access KVM kernel module: %m\n");
 132         ret = -errno;
 133         goto err;
 134     }
 135
 136     ret = kvm_ioctl(s, KVM_GET_API_VERSION, 0);
 137     if (ret < KVM_API_VERSION) {
 138         if (ret > 0)
 139             ret = -EINVAL;
 140         fprintf(stderr, "kvm version too old\n");
 141         goto err;
 142     }
 143
 144     if (ret > KVM_API_VERSION) {
 145         ret = -EINVAL;
 146         fprintf(stderr, "kvm version not supported\n");
 147         goto err;
 148     }
 149
 150     s->vmfd = kvm_ioctl(s, KVM_CREATE_VM, 0);
 151     if (s->vmfd < 0)
 152         goto err;
 153
 154     /* initially, KVM allocated its own memory and we had to jump through
 155      * hooks to make phys_ram_base point to this.  Modern versions of KVM
 156      * just use a user allocated buffer so we can use phys_ram_base
 157      * unmodified.  Make sure we have a sufficiently modern version of KVM.
 158      */
 159     ret = kvm_ioctl(s, KVM_CHECK_EXTENSION, KVM_CAP_USER_MEMORY);
 160     if (ret <= 0) {
 161         if (ret == 0)
 162             ret = -EINVAL;
 163         fprintf(stderr, "kvm does not support KVM_CAP_USER_MEMORY\n");
 164         goto err;
 165     }
 166
 167     ret = kvm_arch_init(s, smp_cpus);
 168     if (ret < 0)
 169         goto err;
 170
 171     kvm_state = s;
 172
 173     return 0;
 174
 175 err:
 176     if (s) {
 177         if (s->vmfd != -1)
 178             close(s->vmfd);
 179         if (s->fd != -1)
 180             close(s->fd);
 181     }
 182     qemu_free(s);
 183
 184     return ret;
 185 }
 186
 187 static int kvm_handle_io(CPUState *env, uint16_t port, void *data,
 188                          int direction, int size, uint32_t count)
 189 {
 190     int i;
 191     uint8_t *ptr = data;
 192
 193     for (i = 0; i < count; i++) {
 194         if (direction == KVM_EXIT_IO_IN) {
 195             switch (size) {
 196             case 1:
 197                 stb_p(ptr, cpu_inb(env, port));
 198                 break;
 199             case 2:
 200                 stw_p(ptr, cpu_inw(env, port));
 201                 break;
 202             case 4:
 203                 stl_p(ptr, cpu_inl(env, port));
 204                 break;
 205             }
 206         } else {
 207             switch (size) {
 208             case 1:
 209                 cpu_outb(env, port, ldub_p(ptr));
 210                 break;
 211             case 2:
 212                 cpu_outw(env, port, lduw_p(ptr));
 213                 break;
 214             case 4:
 215                 cpu_outl(env, port, ldl_p(ptr));
 216                 break;
 217             }
 218         }
 219
 220         ptr += size;
 221     }
 222
 223     return 1;
 224 }
 225
 226 int kvm_cpu_exec(CPUState *env)
 227 {
 228     struct kvm_run *run = env->kvm_run;
 229     int ret;
 230
 231     dprintf("kvm_cpu_exec()\n");
 232
 233     do {
 234         kvm_arch_pre_run(env, run);
 235
 236         if ((env->interrupt_request & CPU_INTERRUPT_EXIT)) {
 237             dprintf("interrupt exit requested\n");
 238             ret = 0;
 239             break;
 240         }
 241
 242         ret = kvm_vcpu_ioctl(env, KVM_RUN, 0);
 243         kvm_arch_post_run(env, run);
 244
 245         if (ret == -EINTR || ret == -EAGAIN) {
 246             dprintf("io window exit\n");
 247             ret = 0;
 248             break;
 249         }
 250
 251         if (ret < 0) {
 252             dprintf("kvm run failed %s\n", strerror(-ret));
 253             abort();
 254         }
 255
 256         ret = 0; /* exit loop */
 257         switch (run->exit_reason) {
 258         case KVM_EXIT_IO:
 259             dprintf("handle_io\n");
 260             ret = kvm_handle_io(env, run->io.port,
 261                                 (uint8_t *)run + run->io.data_offset,
 262                                 run->io.direction,
 263                                 run->io.size,
 264                                 run->io.count);
 265             break;
 266         case KVM_EXIT_MMIO:
 267             dprintf("handle_mmio\n");
 268             cpu_physical_memory_rw(run->mmio.phys_addr,
 269                                    run->mmio.data,
 270                                    run->mmio.len,
 271                                    run->mmio.is_write);
 272             ret = 1;
 273             break;
 274         case KVM_EXIT_IRQ_WINDOW_OPEN:
 275             dprintf("irq_window_open\n");
 276             break;
 277         case KVM_EXIT_SHUTDOWN:
 278             dprintf("shutdown\n");
 279             qemu_system_reset_request();
 280             ret = 1;
 281             break;
 282         case KVM_EXIT_UNKNOWN:
 283             dprintf("kvm_exit_unknown\n");
 284             break;
 285         case KVM_EXIT_FAIL_ENTRY:
 286             dprintf("kvm_exit_fail_entry\n");
 287             break;
 288         case KVM_EXIT_EXCEPTION:
 289             dprintf("kvm_exit_exception\n");
 290             break;
 291         case KVM_EXIT_DEBUG:
 292             dprintf("kvm_exit_debug\n");
 293             break;
 294         default:
 295             dprintf("kvm_arch_handle_exit\n");
 296             ret = kvm_arch_handle_exit(env, run);
 297             break;
 298         }
 299     } while (ret > 0);
 300
 301     if ((env->interrupt_request & CPU_INTERRUPT_EXIT)) {
 302         env->interrupt_request &= ~CPU_INTERRUPT_EXIT;
 303         env->exception_index = EXCP_INTERRUPT;
 304     }
 305
 306     return ret;
 307 }
 308
 309 void kvm_set_phys_mem(target_phys_addr_t start_addr,
 310                       ram_addr_t size,
 311                       ram_addr_t phys_offset)
 312 {
 313     KVMState *s = kvm_state;
 314     ram_addr_t flags = phys_offset & ~TARGET_PAGE_MASK;
 315     KVMSlot *mem;
 316
 317     /* KVM does not support read-only slots */
 318     phys_offset &= ~IO_MEM_ROM;
 319
 320     mem = kvm_lookup_slot(s, start_addr);
 321     if (mem) {
 322         if (flags == IO_MEM_UNASSIGNED) {
 323             mem->memory_size = 0;
 324             mem->guest_phys_addr = start_addr;
 325             mem->userspace_addr = 0;
 326             mem->flags = 0;
 327
 328             kvm_vm_ioctl(s, KVM_SET_USER_MEMORY_REGION, mem);
 329         } else if (start_addr >= mem->guest_phys_addr &&
 330                    (start_addr + size) <= (mem->guest_phys_addr + mem->memory_size))
 331             return;
 332     }
 333
 334     /* KVM does not need to know about this memory */
 335     if (flags >= IO_MEM_UNASSIGNED)
 336         return;
 337
 338     mem = kvm_alloc_slot(s);
 339     mem->memory_size = size;
 340     mem->guest_phys_addr = start_addr;
 341     mem->userspace_addr = (unsigned long)(phys_ram_base + phys_offset);
 342     mem->flags = 0;
 343
 344     kvm_vm_ioctl(s, KVM_SET_USER_MEMORY_REGION, mem);
 345     /* FIXME deal with errors */
 346 }
 347
 348 int kvm_ioctl(KVMState *s, int type, ...)
 349 {
 350     int ret;
 351     void *arg;
 352     va_list ap;
 353
 354     va_start(ap, type);
 355     arg = va_arg(ap, void *);
 356     va_end(ap);
 357
 358     ret = ioctl(s->fd, type, arg);
 359     if (ret == -1)
 360         ret = -errno;
 361
 362     return ret;
 363 }
 364
 365 int kvm_vm_ioctl(KVMState *s, int type, ...)
 366 {
 367     int ret;
 368     void *arg;
 369     va_list ap;
 370
 371     va_start(ap, type);
 372     arg = va_arg(ap, void *);
 373     va_end(ap);
 374
 375     ret = ioctl(s->vmfd, type, arg);
 376     if (ret == -1)
 377         ret = -errno;
 378
 379     return ret;
 380 }
 381
 382 int kvm_vcpu_ioctl(CPUState *env, int type, ...)
 383 {
 384     int ret;
 385     void *arg;
 386     va_list ap;
 387
 388     va_start(ap, type);
 389     arg = va_arg(ap, void *);
 390     va_end(ap);
 391
 392     ret = ioctl(env->kvm_fd, type, arg);
 393     if (ret == -1)
 394         ret = -errno;
 395
 396     return ret;
 397 }