| 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 "exec/target_page.h" |
| 15 | #include "hw/s390x/s390-virtio-ccw.h" |
| 16 | #include "hw/core/qdev-properties.h" |
| 17 | #include "hw/s390x/storage-keys.h" |
| 18 | #include "qapi/error.h" |
| 19 | #include "qapi/qapi-commands-machine.h" |
| 20 | #include "qobject/qdict.h" |
| 21 | #include "qemu/error-report.h" |
| 22 | #include "system/memory_mapping.h" |
| 23 | #include "system/address-spaces.h" |
| 24 | #include "system/kvm.h" |
| 25 | #include "migration/qemu-file-types.h" |
| 26 | #include "migration/register.h" |
| 27 | #include "monitor/hmp.h" |
| 28 | #include "monitor/monitor.h" |
| 29 | #include "trace.h" |
| 30 | |
| 31 | #define S390_SKEYS_BUFFER_SIZE (128 * KiB) /* Room for 128k storage keys */ |
| 32 | #define S390_SKEYS_SAVE_FLAG_EOS 0x01 |
| 33 | #define S390_SKEYS_SAVE_FLAG_SKEYS 0x02 |
| 34 | #define S390_SKEYS_SAVE_FLAG_ERROR 0x04 |
| 35 | |
| 36 | S390SKeysState *s390_get_skeys_device(void) |
| 37 | { |
| 38 | S390SKeysState *ss; |
| 39 | |
| 40 | ss = S390_SKEYS(object_resolve_path_type("", TYPE_S390_SKEYS, NULL)); |
| 41 | assert(ss); |
| 42 | return ss; |
| 43 | } |
| 44 | |
| 45 | void s390_skeys_init(void) |
| 46 | { |
| 47 | Object *obj; |
| 48 | |
| 49 | if (kvm_enabled()) { |
| 50 | obj = object_new(TYPE_KVM_S390_SKEYS); |
| 51 | } else { |
| 52 | obj = object_new(TYPE_QEMU_S390_SKEYS); |
| 53 | } |
| 54 | object_property_add_child(qdev_get_machine(), TYPE_S390_SKEYS, |
| 55 | obj); |
| 56 | object_unref(obj); |
| 57 | |
| 58 | qdev_realize(DEVICE(obj), NULL, &error_fatal); |
| 59 | } |
| 60 | |
| 61 | int s390_skeys_get(S390SKeysState *ks, uint64_t start_gfn, |
| 62 | uint64_t count, uint8_t *keys) |
| 63 | { |
| 64 | S390SKeysClass *kc = S390_SKEYS_GET_CLASS(ks); |
| 65 | int rc; |
| 66 | |
| 67 | rc = kc->get_skeys(ks, start_gfn, count, keys); |
| 68 | if (rc) { |
| 69 | trace_s390_skeys_get_nonzero(rc); |
| 70 | } |
| 71 | return rc; |
| 72 | } |
| 73 | |
| 74 | int s390_skeys_set(S390SKeysState *ks, uint64_t start_gfn, |
| 75 | uint64_t count, uint8_t *keys) |
| 76 | { |
| 77 | S390SKeysClass *kc = S390_SKEYS_GET_CLASS(ks); |
| 78 | int rc; |
| 79 | |
| 80 | rc = kc->set_skeys(ks, start_gfn, count, keys); |
| 81 | if (rc) { |
| 82 | trace_s390_skeys_set_nonzero(rc); |
| 83 | } |
| 84 | return rc; |
| 85 | } |
| 86 | |
| 87 | static void write_keys(FILE *f, uint8_t *keys, uint64_t startgfn, |
| 88 | uint64_t count, Error **errp) |
| 89 | { |
| 90 | uint64_t curpage = startgfn; |
| 91 | uint64_t maxpage = curpage + count - 1; |
| 92 | |
| 93 | for (; curpage <= maxpage; curpage++) { |
| 94 | uint8_t acc = (*keys & 0xF0) >> 4; |
| 95 | int fp = (*keys & 0x08); |
| 96 | int ref = (*keys & 0x04); |
| 97 | int ch = (*keys & 0x02); |
| 98 | int res = (*keys & 0x01); |
| 99 | |
| 100 | fprintf(f, "page=%03" PRIx64 ": key(%d) => ACC=%X, FP=%d, REF=%d," |
| 101 | " ch=%d, reserved=%d\n", |
| 102 | curpage, *keys, acc, fp, ref, ch, res); |
| 103 | keys++; |
| 104 | } |
| 105 | } |
| 106 | |
| 107 | #ifdef CONFIG_HMP |
| 108 | void hmp_info_skeys(MonitorHMP *hmp, const QDict *qdict) |
| 109 | { |
| 110 | S390SKeysState *ss = s390_get_skeys_device(); |
| 111 | S390SKeysClass *skeyclass = S390_SKEYS_GET_CLASS(ss); |
| 112 | uint64_t addr = qdict_get_int(qdict, "addr"); |
| 113 | uint8_t key; |
| 114 | int r; |
| 115 | |
| 116 | /* Quick check to see if guest is using storage keys*/ |
| 117 | if (!skeyclass->skeys_are_enabled(ss)) { |
| 118 | monitor_hmp_printf(hmp, "Error: This guest is not using storage keys\n"); |
| 119 | return; |
| 120 | } |
| 121 | |
| 122 | if (!address_space_access_valid(&address_space_memory, |
| 123 | addr & TARGET_PAGE_MASK, TARGET_PAGE_SIZE, |
| 124 | false, MEMTXATTRS_UNSPECIFIED)) { |
| 125 | monitor_hmp_printf(hmp, "Error: The given address is not valid\n"); |
| 126 | return; |
| 127 | } |
| 128 | |
| 129 | r = skeyclass->get_skeys(ss, addr / TARGET_PAGE_SIZE, 1, &key); |
| 130 | if (r < 0) { |
| 131 | monitor_hmp_printf(hmp, "Error: %s\n", strerror(-r)); |
| 132 | return; |
| 133 | } |
| 134 | |
| 135 | monitor_hmp_printf(hmp, " key: 0x%X\n", key); |
| 136 | } |
| 137 | |
| 138 | void hmp_dump_skeys(MonitorHMP *hmp, const QDict *qdict) |
| 139 | { |
| 140 | const char *filename = qdict_get_str(qdict, "filename"); |
| 141 | Error *err = NULL; |
| 142 | |
| 143 | qmp_dump_skeys(filename, &err); |
| 144 | if (err) { |
| 145 | error_report_err(err); |
| 146 | } |
| 147 | } |
| 148 | #endif |
| 149 | |
| 150 | void s390_qmp_dump_skeys(const char *filename, Error **errp) |
| 151 | { |
| 152 | S390SKeysState *ss = s390_get_skeys_device(); |
| 153 | S390SKeysClass *skeyclass = S390_SKEYS_GET_CLASS(ss); |
| 154 | GuestPhysBlockList guest_phys_blocks; |
| 155 | GuestPhysBlock *block; |
| 156 | uint64_t pages, gfn; |
| 157 | Error *lerr = NULL; |
| 158 | uint8_t *buf; |
| 159 | int ret; |
| 160 | int fd; |
| 161 | FILE *f; |
| 162 | |
| 163 | /* Quick check to see if guest is using storage keys*/ |
| 164 | if (!skeyclass->skeys_are_enabled(ss)) { |
| 165 | error_setg(errp, "This guest is not using storage keys - " |
| 166 | "nothing to dump"); |
| 167 | return; |
| 168 | } |
| 169 | |
| 170 | fd = qemu_open_old(filename, O_WRONLY | O_CREAT | O_TRUNC, 0600); |
| 171 | if (fd < 0) { |
| 172 | error_setg_file_open(errp, errno, filename); |
| 173 | return; |
| 174 | } |
| 175 | f = fdopen(fd, "wb"); |
| 176 | if (!f) { |
| 177 | close(fd); |
| 178 | error_setg_file_open(errp, errno, filename); |
| 179 | return; |
| 180 | } |
| 181 | |
| 182 | buf = g_try_malloc(S390_SKEYS_BUFFER_SIZE); |
| 183 | if (!buf) { |
| 184 | error_setg(errp, "Could not allocate memory"); |
| 185 | goto out; |
| 186 | } |
| 187 | |
| 188 | assert(bql_locked()); |
| 189 | guest_phys_blocks_init(&guest_phys_blocks); |
| 190 | guest_phys_blocks_append(&guest_phys_blocks); |
| 191 | |
| 192 | QTAILQ_FOREACH(block, &guest_phys_blocks.head, next) { |
| 193 | assert(QEMU_IS_ALIGNED(block->target_start, TARGET_PAGE_SIZE)); |
| 194 | assert(QEMU_IS_ALIGNED(block->target_end, TARGET_PAGE_SIZE)); |
| 195 | |
| 196 | gfn = block->target_start / TARGET_PAGE_SIZE; |
| 197 | pages = (block->target_end - block->target_start) / TARGET_PAGE_SIZE; |
| 198 | |
| 199 | while (pages) { |
| 200 | const uint64_t cur_pages = MIN(pages, S390_SKEYS_BUFFER_SIZE); |
| 201 | |
| 202 | ret = skeyclass->get_skeys(ss, gfn, cur_pages, buf); |
| 203 | if (ret < 0) { |
| 204 | error_setg_errno(errp, -ret, "get_keys error"); |
| 205 | goto out_free; |
| 206 | } |
| 207 | |
| 208 | /* write keys to stream */ |
| 209 | write_keys(f, buf, gfn, cur_pages, &lerr); |
| 210 | if (lerr) { |
| 211 | goto out_free; |
| 212 | } |
| 213 | |
| 214 | gfn += cur_pages; |
| 215 | pages -= cur_pages; |
| 216 | } |
| 217 | } |
| 218 | |
| 219 | out_free: |
| 220 | guest_phys_blocks_free(&guest_phys_blocks); |
| 221 | error_propagate(errp, lerr); |
| 222 | g_free(buf); |
| 223 | out: |
| 224 | fclose(f); |
| 225 | } |
| 226 | |
| 227 | static bool qemu_s390_skeys_are_enabled(S390SKeysState *ss) |
| 228 | { |
| 229 | QEMUS390SKeysState *skeys = QEMU_S390_SKEYS(ss); |
| 230 | |
| 231 | /* Lockless check is sufficient. */ |
| 232 | return !!skeys->keydata; |
| 233 | } |
| 234 | |
| 235 | static bool qemu_s390_enable_skeys(S390SKeysState *ss) |
| 236 | { |
| 237 | QEMUS390SKeysState *skeys = QEMU_S390_SKEYS(ss); |
| 238 | static gsize initialized; |
| 239 | |
| 240 | if (likely(skeys->keydata)) { |
| 241 | return true; |
| 242 | } |
| 243 | |
| 244 | /* |
| 245 | * TODO: Modern Linux doesn't use storage keys unless running KVM guests |
| 246 | * that use storage keys. Therefore, we keep it simple for now. |
| 247 | * |
| 248 | * 1) We should initialize to "referenced+changed" for an initial |
| 249 | * over-indication. Let's avoid touching megabytes of data for now and |
| 250 | * assume that any sane user will issue a storage key instruction before |
| 251 | * actually relying on this data. |
| 252 | * 2) Relying on ram_size and allocating a big array is ugly. We should |
| 253 | * allocate and manage storage key data per RAMBlock or optimally using |
| 254 | * some sparse data structure. |
| 255 | * 3) We only ever have a single S390SKeysState, so relying on |
| 256 | * g_once_init_enter() is good enough. |
| 257 | */ |
| 258 | if (g_once_init_enter(&initialized)) { |
| 259 | S390CcwMachineState *s390ms = S390_CCW_MACHINE(qdev_get_machine()); |
| 260 | |
| 261 | skeys->key_count = s390_get_memory_limit(s390ms) / TARGET_PAGE_SIZE; |
| 262 | skeys->keydata = g_malloc0(skeys->key_count); |
| 263 | g_once_init_leave(&initialized, 1); |
| 264 | } |
| 265 | return false; |
| 266 | } |
| 267 | |
| 268 | static int qemu_s390_skeys_set(S390SKeysState *ss, uint64_t start_gfn, |
| 269 | uint64_t count, uint8_t *keys) |
| 270 | { |
| 271 | QEMUS390SKeysState *skeydev = QEMU_S390_SKEYS(ss); |
| 272 | int i; |
| 273 | |
| 274 | /* Check for uint64 overflow and access beyond end of key data */ |
| 275 | if (unlikely(!skeydev->keydata || start_gfn + count > skeydev->key_count || |
| 276 | start_gfn + count < count)) { |
| 277 | error_report("Error: Setting storage keys for pages with unallocated " |
| 278 | "storage key memory: gfn=%" PRIx64 " count=%" PRId64, |
| 279 | start_gfn, count); |
| 280 | return -EINVAL; |
| 281 | } |
| 282 | |
| 283 | for (i = 0; i < count; i++) { |
| 284 | skeydev->keydata[start_gfn + i] = keys[i]; |
| 285 | } |
| 286 | return 0; |
| 287 | } |
| 288 | |
| 289 | static int qemu_s390_skeys_get(S390SKeysState *ss, uint64_t start_gfn, |
| 290 | uint64_t count, uint8_t *keys) |
| 291 | { |
| 292 | QEMUS390SKeysState *skeydev = QEMU_S390_SKEYS(ss); |
| 293 | int i; |
| 294 | |
| 295 | /* Check for uint64 overflow and access beyond end of key data */ |
| 296 | if (unlikely(!skeydev->keydata || start_gfn + count > skeydev->key_count || |
| 297 | start_gfn + count < count)) { |
| 298 | error_report("Error: Getting storage keys for pages with unallocated " |
| 299 | "storage key memory: gfn=%" PRIx64 " count=%" PRId64, |
| 300 | start_gfn, count); |
| 301 | return -EINVAL; |
| 302 | } |
| 303 | |
| 304 | for (i = 0; i < count; i++) { |
| 305 | keys[i] = skeydev->keydata[start_gfn + i]; |
| 306 | } |
| 307 | return 0; |
| 308 | } |
| 309 | |
| 310 | static void qemu_s390_skeys_class_init(ObjectClass *oc, const void *data) |
| 311 | { |
| 312 | S390SKeysClass *skeyclass = S390_SKEYS_CLASS(oc); |
| 313 | DeviceClass *dc = DEVICE_CLASS(oc); |
| 314 | |
| 315 | skeyclass->skeys_are_enabled = qemu_s390_skeys_are_enabled; |
| 316 | skeyclass->enable_skeys = qemu_s390_enable_skeys; |
| 317 | skeyclass->get_skeys = qemu_s390_skeys_get; |
| 318 | skeyclass->set_skeys = qemu_s390_skeys_set; |
| 319 | |
| 320 | /* Reason: Internal device (only one skeys device for the whole memory) */ |
| 321 | dc->user_creatable = false; |
| 322 | } |
| 323 | |
| 324 | static void s390_storage_keys_save(QEMUFile *f, void *opaque) |
| 325 | { |
| 326 | S390SKeysState *ss = S390_SKEYS(opaque); |
| 327 | S390SKeysClass *skeyclass = S390_SKEYS_GET_CLASS(ss); |
| 328 | GuestPhysBlockList guest_phys_blocks; |
| 329 | GuestPhysBlock *block; |
| 330 | uint64_t pages, gfn; |
| 331 | int error = 0; |
| 332 | uint8_t *buf; |
| 333 | |
| 334 | if (!skeyclass->skeys_are_enabled(ss)) { |
| 335 | goto end_stream; |
| 336 | } |
| 337 | |
| 338 | buf = g_try_malloc(S390_SKEYS_BUFFER_SIZE); |
| 339 | if (!buf) { |
| 340 | error_report("storage key save could not allocate memory"); |
| 341 | goto end_stream; |
| 342 | } |
| 343 | |
| 344 | guest_phys_blocks_init(&guest_phys_blocks); |
| 345 | guest_phys_blocks_append(&guest_phys_blocks); |
| 346 | |
| 347 | /* Send each contiguous physical memory range separately. */ |
| 348 | QTAILQ_FOREACH(block, &guest_phys_blocks.head, next) { |
| 349 | assert(QEMU_IS_ALIGNED(block->target_start, TARGET_PAGE_SIZE)); |
| 350 | assert(QEMU_IS_ALIGNED(block->target_end, TARGET_PAGE_SIZE)); |
| 351 | |
| 352 | gfn = block->target_start / TARGET_PAGE_SIZE; |
| 353 | pages = (block->target_end - block->target_start) / TARGET_PAGE_SIZE; |
| 354 | qemu_put_be64(f, block->target_start | S390_SKEYS_SAVE_FLAG_SKEYS); |
| 355 | qemu_put_be64(f, pages); |
| 356 | |
| 357 | while (pages) { |
| 358 | const uint64_t cur_pages = MIN(pages, S390_SKEYS_BUFFER_SIZE); |
| 359 | |
| 360 | if (!error) { |
| 361 | error = skeyclass->get_skeys(ss, gfn, cur_pages, buf); |
| 362 | if (error) { |
| 363 | /* |
| 364 | * Create a valid stream with all 0x00 and indicate |
| 365 | * S390_SKEYS_SAVE_FLAG_ERROR to the destination. |
| 366 | */ |
| 367 | error_report("S390_GET_KEYS error %d", error); |
| 368 | memset(buf, 0, S390_SKEYS_BUFFER_SIZE); |
| 369 | } |
| 370 | } |
| 371 | |
| 372 | qemu_put_buffer(f, buf, cur_pages); |
| 373 | gfn += cur_pages; |
| 374 | pages -= cur_pages; |
| 375 | } |
| 376 | |
| 377 | if (error) { |
| 378 | break; |
| 379 | } |
| 380 | } |
| 381 | |
| 382 | guest_phys_blocks_free(&guest_phys_blocks); |
| 383 | g_free(buf); |
| 384 | end_stream: |
| 385 | if (error) { |
| 386 | qemu_put_be64(f, S390_SKEYS_SAVE_FLAG_ERROR); |
| 387 | } else { |
| 388 | qemu_put_be64(f, S390_SKEYS_SAVE_FLAG_EOS); |
| 389 | } |
| 390 | } |
| 391 | |
| 392 | static int s390_storage_keys_load(QEMUFile *f, void *opaque, int version_id) |
| 393 | { |
| 394 | S390SKeysState *ss = S390_SKEYS(opaque); |
| 395 | S390SKeysClass *skeyclass = S390_SKEYS_GET_CLASS(ss); |
| 396 | int ret = 0; |
| 397 | |
| 398 | /* |
| 399 | * Make sure to lazy-enable if required to be done explicitly. No need to |
| 400 | * flush any TLB as the VM is not running yet. |
| 401 | */ |
| 402 | if (skeyclass->enable_skeys) { |
| 403 | skeyclass->enable_skeys(ss); |
| 404 | } |
| 405 | |
| 406 | while (!ret) { |
| 407 | ram_addr_t addr; |
| 408 | int flags; |
| 409 | |
| 410 | addr = qemu_get_be64(f); |
| 411 | flags = addr & ~TARGET_PAGE_MASK; |
| 412 | addr &= TARGET_PAGE_MASK; |
| 413 | |
| 414 | switch (flags) { |
| 415 | case S390_SKEYS_SAVE_FLAG_SKEYS: { |
| 416 | const uint64_t total_count = qemu_get_be64(f); |
| 417 | uint64_t handled_count = 0, cur_count; |
| 418 | uint64_t cur_gfn = addr / TARGET_PAGE_SIZE; |
| 419 | uint8_t *buf = g_try_malloc(S390_SKEYS_BUFFER_SIZE); |
| 420 | |
| 421 | if (!buf) { |
| 422 | error_report("storage key load could not allocate memory"); |
| 423 | ret = -ENOMEM; |
| 424 | break; |
| 425 | } |
| 426 | |
| 427 | while (handled_count < total_count) { |
| 428 | cur_count = MIN(total_count - handled_count, |
| 429 | S390_SKEYS_BUFFER_SIZE); |
| 430 | qemu_get_buffer(f, buf, cur_count); |
| 431 | |
| 432 | ret = skeyclass->set_skeys(ss, cur_gfn, cur_count, buf); |
| 433 | if (ret < 0) { |
| 434 | error_report("S390_SET_KEYS error %d", ret); |
| 435 | break; |
| 436 | } |
| 437 | handled_count += cur_count; |
| 438 | cur_gfn += cur_count; |
| 439 | } |
| 440 | g_free(buf); |
| 441 | break; |
| 442 | } |
| 443 | case S390_SKEYS_SAVE_FLAG_ERROR: { |
| 444 | error_report("Storage key data is incomplete"); |
| 445 | ret = -EINVAL; |
| 446 | break; |
| 447 | } |
| 448 | case S390_SKEYS_SAVE_FLAG_EOS: |
| 449 | /* normal exit */ |
| 450 | return 0; |
| 451 | default: |
| 452 | error_report("Unexpected storage key flag data: %#x", flags); |
| 453 | ret = -EINVAL; |
| 454 | } |
| 455 | } |
| 456 | |
| 457 | return ret; |
| 458 | } |
| 459 | |
| 460 | static SaveVMHandlers savevm_s390_storage_keys = { |
| 461 | .save_state = s390_storage_keys_save, |
| 462 | .load_state = s390_storage_keys_load, |
| 463 | }; |
| 464 | |
| 465 | static void s390_skeys_realize(DeviceState *dev, Error **errp) |
| 466 | { |
| 467 | S390SKeysState *ss = S390_SKEYS(dev); |
| 468 | |
| 469 | register_savevm_live(TYPE_S390_SKEYS, 0, 1, &savevm_s390_storage_keys, ss); |
| 470 | } |
| 471 | |
| 472 | static void s390_skeys_class_init(ObjectClass *oc, const void *data) |
| 473 | { |
| 474 | DeviceClass *dc = DEVICE_CLASS(oc); |
| 475 | |
| 476 | dc->hotpluggable = false; |
| 477 | dc->realize = s390_skeys_realize; |
| 478 | set_bit(DEVICE_CATEGORY_MISC, dc->categories); |
| 479 | } |
| 480 | |
| 481 | static const TypeInfo s390_skeys_types[] = { |
| 482 | { |
| 483 | .name = TYPE_DUMP_SKEYS_INTERFACE, |
| 484 | .parent = TYPE_INTERFACE, |
| 485 | .class_size = sizeof(DumpSKeysInterface), |
| 486 | }, |
| 487 | { |
| 488 | .name = TYPE_S390_SKEYS, |
| 489 | .parent = TYPE_DEVICE, |
| 490 | .instance_size = sizeof(S390SKeysState), |
| 491 | .class_init = s390_skeys_class_init, |
| 492 | .class_size = sizeof(S390SKeysClass), |
| 493 | .abstract = true, |
| 494 | }, |
| 495 | { |
| 496 | .name = TYPE_QEMU_S390_SKEYS, |
| 497 | .parent = TYPE_S390_SKEYS, |
| 498 | .instance_size = sizeof(QEMUS390SKeysState), |
| 499 | .class_init = qemu_s390_skeys_class_init, |
| 500 | .class_size = sizeof(S390SKeysClass), |
| 501 | }, |
| 502 | }; |
| 503 | |
| 504 | DEFINE_TYPES(s390_skeys_types) |