1 /* 2 * QEMU S390x KVM floating interrupt controller (flic) 3 * 4 * Copyright 2014 IBM Corp. 5 * Author(s): Jens Freimann <jfrei@linux.vnet.ibm.com> 6 * Cornelia Huck <cornelia.huck@de.ibm.com> 7 * 8 * This work is licensed under the terms of the GNU GPL, version 2 or (at 9 * your option) any later version. See the COPYING file in the top-level 10 * directory. 11 */ 12 13 #include "qemu/osdep.h" 14 #include "qemu-common.h" 15 #include "cpu.h" 16 #include <sys/ioctl.h> 17 #include "qemu/error-report.h" 18 #include "hw/sysbus.h" 19 #include "sysemu/kvm.h" 20 #include "migration/qemu-file.h" 21 #include "hw/s390x/s390_flic.h" 22 #include "hw/s390x/adapter.h" 23 #include "trace.h" 24 25 #define FLIC_SAVE_INITIAL_SIZE getpagesize() 26 #define FLIC_FAILED (-1UL) 27 #define FLIC_SAVEVM_VERSION 1 28 29 typedef struct KVMS390FLICState { 30 S390FLICState parent_obj; 31 32 uint32_t fd; 33 bool clear_io_supported; 34 } KVMS390FLICState; 35 36 DeviceState *s390_flic_kvm_create(void) 37 { 38 DeviceState *dev = NULL; 39 40 if (kvm_enabled()) { 41 dev = qdev_create(NULL, TYPE_KVM_S390_FLIC); 42 object_property_add_child(qdev_get_machine(), TYPE_KVM_S390_FLIC, 43 OBJECT(dev), NULL); 44 } 45 return dev; 46 } 47 48 /** 49 * flic_get_all_irqs - store all pending irqs in buffer 50 * @buf: pointer to buffer which is passed to kernel 51 * @len: length of buffer 52 * @flic: pointer to flic device state 53 * 54 * Returns: -ENOMEM if buffer is too small, 55 * -EINVAL if attr.group is invalid, 56 * -EFAULT if copying to userspace failed, 57 * on success return number of stored interrupts 58 */ 59 static int flic_get_all_irqs(KVMS390FLICState *flic, 60 void *buf, int len) 61 { 62 struct kvm_device_attr attr = { 63 .group = KVM_DEV_FLIC_GET_ALL_IRQS, 64 .addr = (uint64_t) buf, 65 .attr = len, 66 }; 67 int rc; 68 69 rc = ioctl(flic->fd, KVM_GET_DEVICE_ATTR, &attr); 70 71 return rc == -1 ? -errno : rc; 72 } 73 74 static void flic_enable_pfault(KVMS390FLICState *flic) 75 { 76 struct kvm_device_attr attr = { 77 .group = KVM_DEV_FLIC_APF_ENABLE, 78 }; 79 int rc; 80 81 rc = ioctl(flic->fd, KVM_SET_DEVICE_ATTR, &attr); 82 83 if (rc) { 84 fprintf(stderr, "flic: couldn't enable pfault\n"); 85 } 86 } 87 88 static void flic_disable_wait_pfault(KVMS390FLICState *flic) 89 { 90 struct kvm_device_attr attr = { 91 .group = KVM_DEV_FLIC_APF_DISABLE_WAIT, 92 }; 93 int rc; 94 95 rc = ioctl(flic->fd, KVM_SET_DEVICE_ATTR, &attr); 96 97 if (rc) { 98 fprintf(stderr, "flic: couldn't disable pfault\n"); 99 } 100 } 101 102 /** flic_enqueue_irqs - returns 0 on success 103 * @buf: pointer to buffer which is passed to kernel 104 * @len: length of buffer 105 * @flic: pointer to flic device state 106 * 107 * Returns: -EINVAL if attr.group is unknown 108 */ 109 static int flic_enqueue_irqs(void *buf, uint64_t len, 110 KVMS390FLICState *flic) 111 { 112 int rc; 113 struct kvm_device_attr attr = { 114 .group = KVM_DEV_FLIC_ENQUEUE, 115 .addr = (uint64_t) buf, 116 .attr = len, 117 }; 118 119 rc = ioctl(flic->fd, KVM_SET_DEVICE_ATTR, &attr); 120 121 return rc ? -errno : 0; 122 } 123 124 int kvm_s390_inject_flic(struct kvm_s390_irq *irq) 125 { 126 static KVMS390FLICState *flic; 127 128 if (unlikely(!flic)) { 129 flic = KVM_S390_FLIC(s390_get_flic()); 130 } 131 return flic_enqueue_irqs(irq, sizeof(*irq), flic); 132 } 133 134 static int kvm_s390_clear_io_flic(S390FLICState *fs, uint16_t subchannel_id, 135 uint16_t subchannel_nr) 136 { 137 KVMS390FLICState *flic = KVM_S390_FLIC(fs); 138 int rc; 139 uint32_t sid = subchannel_id << 16 | subchannel_nr; 140 struct kvm_device_attr attr = { 141 .group = KVM_DEV_FLIC_CLEAR_IO_IRQ, 142 .addr = (uint64_t) &sid, 143 .attr = sizeof(sid), 144 }; 145 if (unlikely(!flic->clear_io_supported)) { 146 return -ENOSYS; 147 } 148 rc = ioctl(flic->fd, KVM_SET_DEVICE_ATTR, &attr); 149 return rc ? -errno : 0; 150 } 151 152 /** 153 * __get_all_irqs - store all pending irqs in buffer 154 * @flic: pointer to flic device state 155 * @buf: pointer to pointer to a buffer 156 * @len: length of buffer 157 * 158 * Returns: return value of flic_get_all_irqs 159 * Note: Retry and increase buffer size until flic_get_all_irqs 160 * either returns a value >= 0 or a negative error code. 161 * -ENOMEM is an exception, which means the buffer is too small 162 * and we should try again. Other negative error codes can be 163 * -EFAULT and -EINVAL which we ignore at this point 164 */ 165 static int __get_all_irqs(KVMS390FLICState *flic, 166 void **buf, int len) 167 { 168 int r; 169 170 do { 171 /* returns -ENOMEM if buffer is too small and number 172 * of queued interrupts on success */ 173 r = flic_get_all_irqs(flic, *buf, len); 174 if (r >= 0) { 175 break; 176 } 177 len *= 2; 178 *buf = g_try_realloc(*buf, len); 179 if (!buf) { 180 return -ENOMEM; 181 } 182 } while (r == -ENOMEM && len <= KVM_S390_FLIC_MAX_BUFFER); 183 184 return r; 185 } 186 187 static int kvm_s390_register_io_adapter(S390FLICState *fs, uint32_t id, 188 uint8_t isc, bool swap, 189 bool is_maskable) 190 { 191 struct kvm_s390_io_adapter adapter = { 192 .id = id, 193 .isc = isc, 194 .maskable = is_maskable, 195 .swap = swap, 196 }; 197 KVMS390FLICState *flic = KVM_S390_FLIC(fs); 198 int r; 199 struct kvm_device_attr attr = { 200 .group = KVM_DEV_FLIC_ADAPTER_REGISTER, 201 .addr = (uint64_t)&adapter, 202 }; 203 204 if (!kvm_check_extension(kvm_state, KVM_CAP_IRQ_ROUTING)) { 205 /* nothing to do */ 206 return 0; 207 } 208 209 r = ioctl(flic->fd, KVM_SET_DEVICE_ATTR, &attr); 210 211 return r ? -errno : 0; 212 } 213 214 static int kvm_s390_io_adapter_map(S390FLICState *fs, uint32_t id, 215 uint64_t map_addr, bool do_map) 216 { 217 struct kvm_s390_io_adapter_req req = { 218 .id = id, 219 .type = do_map ? KVM_S390_IO_ADAPTER_MAP : KVM_S390_IO_ADAPTER_UNMAP, 220 .addr = map_addr, 221 }; 222 struct kvm_device_attr attr = { 223 .group = KVM_DEV_FLIC_ADAPTER_MODIFY, 224 .addr = (uint64_t)&req, 225 }; 226 KVMS390FLICState *flic = KVM_S390_FLIC(fs); 227 int r; 228 229 if (!kvm_check_extension(kvm_state, KVM_CAP_IRQ_ROUTING)) { 230 /* nothing to do */ 231 return 0; 232 } 233 234 r = ioctl(flic->fd, KVM_SET_DEVICE_ATTR, &attr); 235 return r ? -errno : 0; 236 } 237 238 static int kvm_s390_add_adapter_routes(S390FLICState *fs, 239 AdapterRoutes *routes) 240 { 241 int ret, i; 242 uint64_t ind_offset = routes->adapter.ind_offset; 243 244 for (i = 0; i < routes->num_routes; i++) { 245 ret = kvm_irqchip_add_adapter_route(kvm_state, &routes->adapter); 246 if (ret < 0) { 247 goto out_undo; 248 } 249 routes->gsi[i] = ret; 250 routes->adapter.ind_offset++; 251 } 252 kvm_irqchip_commit_routes(kvm_state); 253 254 /* Restore passed-in structure to original state. */ 255 routes->adapter.ind_offset = ind_offset; 256 return 0; 257 out_undo: 258 while (--i >= 0) { 259 kvm_irqchip_release_virq(kvm_state, routes->gsi[i]); 260 routes->gsi[i] = -1; 261 } 262 routes->adapter.ind_offset = ind_offset; 263 return ret; 264 } 265 266 static void kvm_s390_release_adapter_routes(S390FLICState *fs, 267 AdapterRoutes *routes) 268 { 269 int i; 270 271 for (i = 0; i < routes->num_routes; i++) { 272 if (routes->gsi[i] >= 0) { 273 kvm_irqchip_release_virq(kvm_state, routes->gsi[i]); 274 routes->gsi[i] = -1; 275 } 276 } 277 } 278 279 /** 280 * kvm_flic_save - Save pending floating interrupts 281 * @f: QEMUFile containing migration state 282 * @opaque: pointer to flic device state 283 * 284 * Note: Pass buf and len to kernel. Start with one page and 285 * increase until buffer is sufficient or maxium size is 286 * reached 287 */ 288 static void kvm_flic_save(QEMUFile *f, void *opaque) 289 { 290 KVMS390FLICState *flic = opaque; 291 int len = FLIC_SAVE_INITIAL_SIZE; 292 void *buf; 293 int count; 294 295 flic_disable_wait_pfault((struct KVMS390FLICState *) opaque); 296 297 buf = g_try_malloc0(len); 298 if (!buf) { 299 /* Storing FLIC_FAILED into the count field here will cause the 300 * target system to fail when attempting to load irqs from the 301 * migration state */ 302 error_report("flic: couldn't allocate memory"); 303 qemu_put_be64(f, FLIC_FAILED); 304 return; 305 } 306 307 count = __get_all_irqs(flic, &buf, len); 308 if (count < 0) { 309 error_report("flic: couldn't retrieve irqs from kernel, rc %d", 310 count); 311 /* Storing FLIC_FAILED into the count field here will cause the 312 * target system to fail when attempting to load irqs from the 313 * migration state */ 314 qemu_put_be64(f, FLIC_FAILED); 315 } else { 316 qemu_put_be64(f, count); 317 qemu_put_buffer(f, (uint8_t *) buf, 318 count * sizeof(struct kvm_s390_irq)); 319 } 320 g_free(buf); 321 } 322 323 /** 324 * kvm_flic_load - Load pending floating interrupts 325 * @f: QEMUFile containing migration state 326 * @opaque: pointer to flic device state 327 * @version_id: version id for migration 328 * 329 * Returns: value of flic_enqueue_irqs, -EINVAL on error 330 * Note: Do nothing when no interrupts where stored 331 * in QEMUFile 332 */ 333 static int kvm_flic_load(QEMUFile *f, void *opaque, int version_id) 334 { 335 uint64_t len = 0; 336 uint64_t count = 0; 337 void *buf = NULL; 338 int r = 0; 339 340 if (version_id != FLIC_SAVEVM_VERSION) { 341 r = -EINVAL; 342 goto out; 343 } 344 345 flic_enable_pfault((struct KVMS390FLICState *) opaque); 346 347 count = qemu_get_be64(f); 348 len = count * sizeof(struct kvm_s390_irq); 349 if (count == FLIC_FAILED) { 350 r = -EINVAL; 351 goto out; 352 } 353 if (count == 0) { 354 r = 0; 355 goto out; 356 } 357 buf = g_try_malloc0(len); 358 if (!buf) { 359 r = -ENOMEM; 360 goto out; 361 } 362 363 if (qemu_get_buffer(f, (uint8_t *) buf, len) != len) { 364 r = -EINVAL; 365 goto out_free; 366 } 367 r = flic_enqueue_irqs(buf, len, (struct KVMS390FLICState *) opaque); 368 369 out_free: 370 g_free(buf); 371 out: 372 return r; 373 } 374 375 static void kvm_s390_flic_realize(DeviceState *dev, Error **errp) 376 { 377 KVMS390FLICState *flic_state = KVM_S390_FLIC(dev); 378 struct kvm_create_device cd = {0}; 379 struct kvm_device_attr test_attr = {0}; 380 int ret; 381 382 flic_state->fd = -1; 383 if (!kvm_check_extension(kvm_state, KVM_CAP_DEVICE_CTRL)) { 384 trace_flic_no_device_api(errno); 385 return; 386 } 387 388 cd.type = KVM_DEV_TYPE_FLIC; 389 ret = kvm_vm_ioctl(kvm_state, KVM_CREATE_DEVICE, &cd); 390 if (ret < 0) { 391 trace_flic_create_device(errno); 392 return; 393 } 394 flic_state->fd = cd.fd; 395 396 /* Check clear_io_irq support */ 397 test_attr.group = KVM_DEV_FLIC_CLEAR_IO_IRQ; 398 flic_state->clear_io_supported = !ioctl(flic_state->fd, 399 KVM_HAS_DEVICE_ATTR, test_attr); 400 401 /* Register savevm handler for floating interrupts */ 402 register_savevm(NULL, "s390-flic", 0, 1, kvm_flic_save, 403 kvm_flic_load, (void *) flic_state); 404 } 405 406 static void kvm_s390_flic_unrealize(DeviceState *dev, Error **errp) 407 { 408 KVMS390FLICState *flic_state = KVM_S390_FLIC(dev); 409 410 unregister_savevm(DEVICE(flic_state), "s390-flic", flic_state); 411 } 412 413 static void kvm_s390_flic_reset(DeviceState *dev) 414 { 415 KVMS390FLICState *flic = KVM_S390_FLIC(dev); 416 struct kvm_device_attr attr = { 417 .group = KVM_DEV_FLIC_CLEAR_IRQS, 418 }; 419 int rc = 0; 420 421 if (flic->fd == -1) { 422 return; 423 } 424 425 flic_disable_wait_pfault(flic); 426 427 rc = ioctl(flic->fd, KVM_SET_DEVICE_ATTR, &attr); 428 if (rc) { 429 trace_flic_reset_failed(errno); 430 } 431 432 flic_enable_pfault(flic); 433 } 434 435 static void kvm_s390_flic_class_init(ObjectClass *oc, void *data) 436 { 437 DeviceClass *dc = DEVICE_CLASS(oc); 438 S390FLICStateClass *fsc = S390_FLIC_COMMON_CLASS(oc); 439 440 dc->realize = kvm_s390_flic_realize; 441 dc->unrealize = kvm_s390_flic_unrealize; 442 dc->reset = kvm_s390_flic_reset; 443 fsc->register_io_adapter = kvm_s390_register_io_adapter; 444 fsc->io_adapter_map = kvm_s390_io_adapter_map; 445 fsc->add_adapter_routes = kvm_s390_add_adapter_routes; 446 fsc->release_adapter_routes = kvm_s390_release_adapter_routes; 447 fsc->clear_io_irq = kvm_s390_clear_io_flic; 448 } 449 450 static const TypeInfo kvm_s390_flic_info = { 451 .name = TYPE_KVM_S390_FLIC, 452 .parent = TYPE_S390_FLIC_COMMON, 453 .instance_size = sizeof(KVMS390FLICState), 454 .class_init = kvm_s390_flic_class_init, 455 }; 456 457 static void kvm_s390_flic_register_types(void) 458 { 459 type_register_static(&kvm_s390_flic_info); 460 } 461 462 type_init(kvm_s390_flic_register_types) 463