1 /* 2 * s390 storage key device 3 * 4 * Copyright 2015 IBM Corp. 5 * Author(s): Jason J. Herne <jjherne@linux.vnet.ibm.com> 6 * 7 * This work is licensed under the terms of the GNU GPL, version 2 or (at 8 * your option) any later version. See the COPYING file in the top-level 9 * directory. 10 */ 11 12 #include "qemu/osdep.h" 13 #include "qemu/units.h" 14 #include "hw/boards.h" 15 #include "hw/s390x/storage-keys.h" 16 #include "qapi/error.h" 17 #include "qapi/qapi-commands-misc-target.h" 18 #include "qapi/qmp/qdict.h" 19 #include "qemu/error-report.h" 20 #include "sysemu/kvm.h" 21 #include "migration/qemu-file-types.h" 22 #include "migration/register.h" 23 24 #define S390_SKEYS_BUFFER_SIZE (128 * KiB) /* Room for 128k storage keys */ 25 #define S390_SKEYS_SAVE_FLAG_EOS 0x01 26 #define S390_SKEYS_SAVE_FLAG_SKEYS 0x02 27 #define S390_SKEYS_SAVE_FLAG_ERROR 0x04 28 29 S390SKeysState *s390_get_skeys_device(void) 30 { 31 S390SKeysState *ss; 32 33 ss = S390_SKEYS(object_resolve_path_type("", TYPE_S390_SKEYS, NULL)); 34 assert(ss); 35 return ss; 36 } 37 38 void s390_skeys_init(void) 39 { 40 Object *obj; 41 42 if (kvm_enabled()) { 43 obj = object_new(TYPE_KVM_S390_SKEYS); 44 } else { 45 obj = object_new(TYPE_QEMU_S390_SKEYS); 46 } 47 object_property_add_child(qdev_get_machine(), TYPE_S390_SKEYS, 48 obj, NULL); 49 object_unref(obj); 50 51 qdev_init_nofail(DEVICE(obj)); 52 } 53 54 static void write_keys(FILE *f, uint8_t *keys, uint64_t startgfn, 55 uint64_t count, Error **errp) 56 { 57 uint64_t curpage = startgfn; 58 uint64_t maxpage = curpage + count - 1; 59 60 for (; curpage <= maxpage; curpage++) { 61 uint8_t acc = (*keys & 0xF0) >> 4; 62 int fp = (*keys & 0x08); 63 int ref = (*keys & 0x04); 64 int ch = (*keys & 0x02); 65 int res = (*keys & 0x01); 66 67 fprintf(f, "page=%03" PRIx64 ": key(%d) => ACC=%X, FP=%d, REF=%d," 68 " ch=%d, reserved=%d\n", 69 curpage, *keys, acc, fp, ref, ch, res); 70 keys++; 71 } 72 } 73 74 void hmp_info_skeys(Monitor *mon, const QDict *qdict) 75 { 76 S390SKeysState *ss = s390_get_skeys_device(); 77 S390SKeysClass *skeyclass = S390_SKEYS_GET_CLASS(ss); 78 uint64_t addr = qdict_get_int(qdict, "addr"); 79 uint8_t key; 80 int r; 81 82 /* Quick check to see if guest is using storage keys*/ 83 if (!skeyclass->skeys_enabled(ss)) { 84 monitor_printf(mon, "Error: This guest is not using storage keys\n"); 85 return; 86 } 87 88 r = skeyclass->get_skeys(ss, addr / TARGET_PAGE_SIZE, 1, &key); 89 if (r < 0) { 90 monitor_printf(mon, "Error: %s\n", strerror(-r)); 91 return; 92 } 93 94 monitor_printf(mon, " key: 0x%X\n", key); 95 } 96 97 void hmp_dump_skeys(Monitor *mon, const QDict *qdict) 98 { 99 const char *filename = qdict_get_str(qdict, "filename"); 100 Error *err = NULL; 101 102 qmp_dump_skeys(filename, &err); 103 if (err) { 104 error_report_err(err); 105 } 106 } 107 108 void qmp_dump_skeys(const char *filename, Error **errp) 109 { 110 S390SKeysState *ss = s390_get_skeys_device(); 111 S390SKeysClass *skeyclass = S390_SKEYS_GET_CLASS(ss); 112 const uint64_t total_count = ram_size / TARGET_PAGE_SIZE; 113 uint64_t handled_count = 0, cur_count; 114 Error *lerr = NULL; 115 vaddr cur_gfn = 0; 116 uint8_t *buf; 117 int ret; 118 int fd; 119 FILE *f; 120 121 /* Quick check to see if guest is using storage keys*/ 122 if (!skeyclass->skeys_enabled(ss)) { 123 error_setg(errp, "This guest is not using storage keys - " 124 "nothing to dump"); 125 return; 126 } 127 128 fd = qemu_open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0600); 129 if (fd < 0) { 130 error_setg_file_open(errp, errno, filename); 131 return; 132 } 133 f = fdopen(fd, "wb"); 134 if (!f) { 135 close(fd); 136 error_setg_file_open(errp, errno, filename); 137 return; 138 } 139 140 buf = g_try_malloc(S390_SKEYS_BUFFER_SIZE); 141 if (!buf) { 142 error_setg(errp, "Could not allocate memory"); 143 goto out; 144 } 145 146 /* we'll only dump initial memory for now */ 147 while (handled_count < total_count) { 148 /* Calculate how many keys to ask for & handle overflow case */ 149 cur_count = MIN(total_count - handled_count, S390_SKEYS_BUFFER_SIZE); 150 151 ret = skeyclass->get_skeys(ss, cur_gfn, cur_count, buf); 152 if (ret < 0) { 153 error_setg(errp, "get_keys error %d", ret); 154 goto out_free; 155 } 156 157 /* write keys to stream */ 158 write_keys(f, buf, cur_gfn, cur_count, &lerr); 159 if (lerr) { 160 goto out_free; 161 } 162 163 cur_gfn += cur_count; 164 handled_count += cur_count; 165 } 166 167 out_free: 168 error_propagate(errp, lerr); 169 g_free(buf); 170 out: 171 fclose(f); 172 } 173 174 static void qemu_s390_skeys_init(Object *obj) 175 { 176 QEMUS390SKeysState *skeys = QEMU_S390_SKEYS(obj); 177 MachineState *machine = MACHINE(qdev_get_machine()); 178 179 skeys->key_count = machine->ram_size / TARGET_PAGE_SIZE; 180 skeys->keydata = g_malloc0(skeys->key_count); 181 } 182 183 static int qemu_s390_skeys_enabled(S390SKeysState *ss) 184 { 185 return 1; 186 } 187 188 /* 189 * TODO: for memory hotplug support qemu_s390_skeys_set and qemu_s390_skeys_get 190 * will have to make sure that the given gfn belongs to a memory region and not 191 * a memory hole. 192 */ 193 static int qemu_s390_skeys_set(S390SKeysState *ss, uint64_t start_gfn, 194 uint64_t count, uint8_t *keys) 195 { 196 QEMUS390SKeysState *skeydev = QEMU_S390_SKEYS(ss); 197 int i; 198 199 /* Check for uint64 overflow and access beyond end of key data */ 200 if (start_gfn + count > skeydev->key_count || start_gfn + count < count) { 201 error_report("Error: Setting storage keys for page beyond the end " 202 "of memory: gfn=%" PRIx64 " count=%" PRId64, 203 start_gfn, count); 204 return -EINVAL; 205 } 206 207 for (i = 0; i < count; i++) { 208 skeydev->keydata[start_gfn + i] = keys[i]; 209 } 210 return 0; 211 } 212 213 static int qemu_s390_skeys_get(S390SKeysState *ss, uint64_t start_gfn, 214 uint64_t count, uint8_t *keys) 215 { 216 QEMUS390SKeysState *skeydev = QEMU_S390_SKEYS(ss); 217 int i; 218 219 /* Check for uint64 overflow and access beyond end of key data */ 220 if (start_gfn + count > skeydev->key_count || start_gfn + count < count) { 221 error_report("Error: Getting storage keys for page beyond the end " 222 "of memory: gfn=%" PRIx64 " count=%" PRId64, 223 start_gfn, count); 224 return -EINVAL; 225 } 226 227 for (i = 0; i < count; i++) { 228 keys[i] = skeydev->keydata[start_gfn + i]; 229 } 230 return 0; 231 } 232 233 static void qemu_s390_skeys_class_init(ObjectClass *oc, void *data) 234 { 235 S390SKeysClass *skeyclass = S390_SKEYS_CLASS(oc); 236 DeviceClass *dc = DEVICE_CLASS(oc); 237 238 skeyclass->skeys_enabled = qemu_s390_skeys_enabled; 239 skeyclass->get_skeys = qemu_s390_skeys_get; 240 skeyclass->set_skeys = qemu_s390_skeys_set; 241 242 /* Reason: Internal device (only one skeys device for the whole memory) */ 243 dc->user_creatable = false; 244 } 245 246 static const TypeInfo qemu_s390_skeys_info = { 247 .name = TYPE_QEMU_S390_SKEYS, 248 .parent = TYPE_S390_SKEYS, 249 .instance_init = qemu_s390_skeys_init, 250 .instance_size = sizeof(QEMUS390SKeysState), 251 .class_init = qemu_s390_skeys_class_init, 252 .class_size = sizeof(S390SKeysClass), 253 }; 254 255 static void s390_storage_keys_save(QEMUFile *f, void *opaque) 256 { 257 S390SKeysState *ss = S390_SKEYS(opaque); 258 S390SKeysClass *skeyclass = S390_SKEYS_GET_CLASS(ss); 259 uint64_t pages_left = ram_size / TARGET_PAGE_SIZE; 260 uint64_t read_count, eos = S390_SKEYS_SAVE_FLAG_EOS; 261 vaddr cur_gfn = 0; 262 int error = 0; 263 uint8_t *buf; 264 265 if (!skeyclass->skeys_enabled(ss)) { 266 goto end_stream; 267 } 268 269 buf = g_try_malloc(S390_SKEYS_BUFFER_SIZE); 270 if (!buf) { 271 error_report("storage key save could not allocate memory"); 272 goto end_stream; 273 } 274 275 /* We only support initial memory. Standby memory is not handled yet. */ 276 qemu_put_be64(f, (cur_gfn * TARGET_PAGE_SIZE) | S390_SKEYS_SAVE_FLAG_SKEYS); 277 qemu_put_be64(f, pages_left); 278 279 while (pages_left) { 280 read_count = MIN(pages_left, S390_SKEYS_BUFFER_SIZE); 281 282 if (!error) { 283 error = skeyclass->get_skeys(ss, cur_gfn, read_count, buf); 284 if (error) { 285 /* 286 * If error: we want to fill the stream with valid data instead 287 * of stopping early so we pad the stream with 0x00 values and 288 * use S390_SKEYS_SAVE_FLAG_ERROR to indicate failure to the 289 * reading side. 290 */ 291 error_report("S390_GET_KEYS error %d", error); 292 memset(buf, 0, S390_SKEYS_BUFFER_SIZE); 293 eos = S390_SKEYS_SAVE_FLAG_ERROR; 294 } 295 } 296 297 qemu_put_buffer(f, buf, read_count); 298 cur_gfn += read_count; 299 pages_left -= read_count; 300 } 301 302 g_free(buf); 303 end_stream: 304 qemu_put_be64(f, eos); 305 } 306 307 static int s390_storage_keys_load(QEMUFile *f, void *opaque, int version_id) 308 { 309 S390SKeysState *ss = S390_SKEYS(opaque); 310 S390SKeysClass *skeyclass = S390_SKEYS_GET_CLASS(ss); 311 int ret = 0; 312 313 while (!ret) { 314 ram_addr_t addr; 315 int flags; 316 317 addr = qemu_get_be64(f); 318 flags = addr & ~TARGET_PAGE_MASK; 319 addr &= TARGET_PAGE_MASK; 320 321 switch (flags) { 322 case S390_SKEYS_SAVE_FLAG_SKEYS: { 323 const uint64_t total_count = qemu_get_be64(f); 324 uint64_t handled_count = 0, cur_count; 325 uint64_t cur_gfn = addr / TARGET_PAGE_SIZE; 326 uint8_t *buf = g_try_malloc(S390_SKEYS_BUFFER_SIZE); 327 328 if (!buf) { 329 error_report("storage key load could not allocate memory"); 330 ret = -ENOMEM; 331 break; 332 } 333 334 while (handled_count < total_count) { 335 cur_count = MIN(total_count - handled_count, 336 S390_SKEYS_BUFFER_SIZE); 337 qemu_get_buffer(f, buf, cur_count); 338 339 ret = skeyclass->set_skeys(ss, cur_gfn, cur_count, buf); 340 if (ret < 0) { 341 error_report("S390_SET_KEYS error %d", ret); 342 break; 343 } 344 handled_count += cur_count; 345 cur_gfn += cur_count; 346 } 347 g_free(buf); 348 break; 349 } 350 case S390_SKEYS_SAVE_FLAG_ERROR: { 351 error_report("Storage key data is incomplete"); 352 ret = -EINVAL; 353 break; 354 } 355 case S390_SKEYS_SAVE_FLAG_EOS: 356 /* normal exit */ 357 return 0; 358 default: 359 error_report("Unexpected storage key flag data: %#x", flags); 360 ret = -EINVAL; 361 } 362 } 363 364 return ret; 365 } 366 367 static inline bool s390_skeys_get_migration_enabled(Object *obj, Error **errp) 368 { 369 S390SKeysState *ss = S390_SKEYS(obj); 370 371 return ss->migration_enabled; 372 } 373 374 static SaveVMHandlers savevm_s390_storage_keys = { 375 .save_state = s390_storage_keys_save, 376 .load_state = s390_storage_keys_load, 377 }; 378 379 static inline void s390_skeys_set_migration_enabled(Object *obj, bool value, 380 Error **errp) 381 { 382 S390SKeysState *ss = S390_SKEYS(obj); 383 384 /* Prevent double registration of savevm handler */ 385 if (ss->migration_enabled == value) { 386 return; 387 } 388 389 ss->migration_enabled = value; 390 391 if (ss->migration_enabled) { 392 register_savevm_live(TYPE_S390_SKEYS, 0, 1, 393 &savevm_s390_storage_keys, ss); 394 } else { 395 unregister_savevm(VMSTATE_IF(ss), TYPE_S390_SKEYS, ss); 396 } 397 } 398 399 static void s390_skeys_instance_init(Object *obj) 400 { 401 object_property_add_bool(obj, "migration-enabled", 402 s390_skeys_get_migration_enabled, 403 s390_skeys_set_migration_enabled, NULL); 404 object_property_set_bool(obj, true, "migration-enabled", NULL); 405 } 406 407 static void s390_skeys_class_init(ObjectClass *oc, void *data) 408 { 409 DeviceClass *dc = DEVICE_CLASS(oc); 410 411 dc->hotpluggable = false; 412 set_bit(DEVICE_CATEGORY_MISC, dc->categories); 413 } 414 415 static const TypeInfo s390_skeys_info = { 416 .name = TYPE_S390_SKEYS, 417 .parent = TYPE_DEVICE, 418 .instance_init = s390_skeys_instance_init, 419 .instance_size = sizeof(S390SKeysState), 420 .class_init = s390_skeys_class_init, 421 .class_size = sizeof(S390SKeysClass), 422 .abstract = true, 423 }; 424 425 static void qemu_s390_skeys_register_types(void) 426 { 427 type_register_static(&s390_skeys_info); 428 type_register_static(&qemu_s390_skeys_info); 429 } 430 431 type_init(qemu_s390_skeys_register_types) 432