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