hw/s390x/s390-skeys.c

   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/memory_mapping.h"
  21 #include "sysemu/kvm.h"
  22 #include "migration/qemu-file-types.h"
  23 #include "migration/register.h"
  24
  25 #define S390_SKEYS_BUFFER_SIZE (128 * KiB)  /* Room for 128k storage keys */
  26 #define S390_SKEYS_SAVE_FLAG_EOS 0x01
  27 #define S390_SKEYS_SAVE_FLAG_SKEYS 0x02
  28 #define S390_SKEYS_SAVE_FLAG_ERROR 0x04
  29
  30 S390SKeysState *s390_get_skeys_device(void)
  31 {
  32     S390SKeysState *ss;
  33
  34     ss = S390_SKEYS(object_resolve_path_type("", TYPE_S390_SKEYS, NULL));
  35     assert(ss);
  36     return ss;
  37 }
  38
  39 void s390_skeys_init(void)
  40 {
  41     Object *obj;
  42
  43     if (kvm_enabled()) {
  44         obj = object_new(TYPE_KVM_S390_SKEYS);
  45     } else {
  46         obj = object_new(TYPE_QEMU_S390_SKEYS);
  47     }
  48     object_property_add_child(qdev_get_machine(), TYPE_S390_SKEYS,
  49                               obj);
  50     object_unref(obj);
  51
  52     qdev_realize(DEVICE(obj), NULL, &error_fatal);
  53 }
  54
  55 static void write_keys(FILE *f, uint8_t *keys, uint64_t startgfn,
  56                        uint64_t count, Error **errp)
  57 {
  58     uint64_t curpage = startgfn;
  59     uint64_t maxpage = curpage + count - 1;
  60
  61     for (; curpage <= maxpage; curpage++) {
  62         uint8_t acc = (*keys & 0xF0) >> 4;
  63         int fp =  (*keys & 0x08);
  64         int ref = (*keys & 0x04);
  65         int ch = (*keys & 0x02);
  66         int res = (*keys & 0x01);
  67
  68         fprintf(f, "page=%03" PRIx64 ": key(%d) => ACC=%X, FP=%d, REF=%d,"
  69                 " ch=%d, reserved=%d\n",
  70                 curpage, *keys, acc, fp, ref, ch, res);
  71         keys++;
  72     }
  73 }
  74
  75 void hmp_info_skeys(Monitor *mon, const QDict *qdict)
  76 {
  77     S390SKeysState *ss = s390_get_skeys_device();
  78     S390SKeysClass *skeyclass = S390_SKEYS_GET_CLASS(ss);
  79     uint64_t addr = qdict_get_int(qdict, "addr");
  80     uint8_t key;
  81     int r;
  82
  83     /* Quick check to see if guest is using storage keys*/
  84     if (!skeyclass->skeys_enabled(ss)) {
  85         monitor_printf(mon, "Error: This guest is not using storage keys\n");
  86         return;
  87     }
  88
  89     r = skeyclass->get_skeys(ss, addr / TARGET_PAGE_SIZE, 1, &key);
  90     if (r < 0) {
  91         monitor_printf(mon, "Error: %s\n", strerror(-r));
  92         return;
  93     }
  94
  95     monitor_printf(mon, "  key: 0x%X\n", key);
  96 }
  97
  98 void hmp_dump_skeys(Monitor *mon, const QDict *qdict)
  99 {
 100     const char *filename = qdict_get_str(qdict, "filename");
 101     Error *err = NULL;
 102
 103     qmp_dump_skeys(filename, &err);
 104     if (err) {
 105         error_report_err(err);
 106     }
 107 }
 108
 109 void qmp_dump_skeys(const char *filename, Error **errp)
 110 {
 111     S390SKeysState *ss = s390_get_skeys_device();
 112     S390SKeysClass *skeyclass = S390_SKEYS_GET_CLASS(ss);
 113     MachineState *ms = MACHINE(qdev_get_machine());
 114     const uint64_t total_count = ms->ram_size / TARGET_PAGE_SIZE;
 115     uint64_t handled_count = 0, cur_count;
 116     Error *lerr = NULL;
 117     vaddr cur_gfn = 0;
 118     uint8_t *buf;
 119     int ret;
 120     int fd;
 121     FILE *f;
 122
 123     /* Quick check to see if guest is using storage keys*/
 124     if (!skeyclass->skeys_enabled(ss)) {
 125         error_setg(errp, "This guest is not using storage keys - "
 126                          "nothing to dump");
 127         return;
 128     }
 129
 130     fd = qemu_open_old(filename, O_WRONLY | O_CREAT | O_TRUNC, 0600);
 131     if (fd < 0) {
 132         error_setg_file_open(errp, errno, filename);
 133         return;
 134     }
 135     f = fdopen(fd, "wb");
 136     if (!f) {
 137         close(fd);
 138         error_setg_file_open(errp, errno, filename);
 139         return;
 140     }
 141
 142     buf = g_try_malloc(S390_SKEYS_BUFFER_SIZE);
 143     if (!buf) {
 144         error_setg(errp, "Could not allocate memory");
 145         goto out;
 146     }
 147
 148     /* we'll only dump initial memory for now */
 149     while (handled_count < total_count) {
 150         /* Calculate how many keys to ask for & handle overflow case */
 151         cur_count = MIN(total_count - handled_count, S390_SKEYS_BUFFER_SIZE);
 152
 153         ret = skeyclass->get_skeys(ss, cur_gfn, cur_count, buf);
 154         if (ret < 0) {
 155             error_setg(errp, "get_keys error %d", ret);
 156             goto out_free;
 157         }
 158
 159         /* write keys to stream */
 160         write_keys(f, buf, cur_gfn, cur_count, &lerr);
 161         if (lerr) {
 162             goto out_free;
 163         }
 164
 165         cur_gfn += cur_count;
 166         handled_count += cur_count;
 167     }
 168
 169 out_free:
 170     error_propagate(errp, lerr);
 171     g_free(buf);
 172 out:
 173     fclose(f);
 174 }
 175
 176 static void qemu_s390_skeys_init(Object *obj)
 177 {
 178     QEMUS390SKeysState *skeys = QEMU_S390_SKEYS(obj);
 179     MachineState *machine = MACHINE(qdev_get_machine());
 180
 181     skeys->key_count = machine->ram_size / TARGET_PAGE_SIZE;
 182     skeys->keydata = g_malloc0(skeys->key_count);
 183 }
 184
 185 static int qemu_s390_skeys_enabled(S390SKeysState *ss)
 186 {
 187     return 1;
 188 }
 189
 190 /*
 191  * TODO: for memory hotplug support qemu_s390_skeys_set and qemu_s390_skeys_get
 192  * will have to make sure that the given gfn belongs to a memory region and not
 193  * a memory hole.
 194  */
 195 static int qemu_s390_skeys_set(S390SKeysState *ss, uint64_t start_gfn,
 196                               uint64_t count, uint8_t *keys)
 197 {
 198     QEMUS390SKeysState *skeydev = QEMU_S390_SKEYS(ss);
 199     int i;
 200
 201     /* Check for uint64 overflow and access beyond end of key data */
 202     if (start_gfn + count > skeydev->key_count || start_gfn + count < count) {
 203         error_report("Error: Setting storage keys for page beyond the end "
 204                      "of memory: gfn=%" PRIx64 " count=%" PRId64,
 205                      start_gfn, count);
 206         return -EINVAL;
 207     }
 208
 209     for (i = 0; i < count; i++) {
 210         skeydev->keydata[start_gfn + i] = keys[i];
 211     }
 212     return 0;
 213 }
 214
 215 static int qemu_s390_skeys_get(S390SKeysState *ss, uint64_t start_gfn,
 216                                uint64_t count, uint8_t *keys)
 217 {
 218     QEMUS390SKeysState *skeydev = QEMU_S390_SKEYS(ss);
 219     int i;
 220
 221     /* Check for uint64 overflow and access beyond end of key data */
 222     if (start_gfn + count > skeydev->key_count || start_gfn + count < count) {
 223         error_report("Error: Getting storage keys for page beyond the end "
 224                      "of memory: gfn=%" PRIx64 " count=%" PRId64,
 225                      start_gfn, count);
 226         return -EINVAL;
 227     }
 228
 229     for (i = 0; i < count; i++) {
 230         keys[i] = skeydev->keydata[start_gfn + i];
 231     }
 232     return 0;
 233 }
 234
 235 static void qemu_s390_skeys_class_init(ObjectClass *oc, void *data)
 236 {
 237     S390SKeysClass *skeyclass = S390_SKEYS_CLASS(oc);
 238     DeviceClass *dc = DEVICE_CLASS(oc);
 239
 240     skeyclass->skeys_enabled = qemu_s390_skeys_enabled;
 241     skeyclass->get_skeys = qemu_s390_skeys_get;
 242     skeyclass->set_skeys = qemu_s390_skeys_set;
 243
 244     /* Reason: Internal device (only one skeys device for the whole memory) */
 245     dc->user_creatable = false;
 246 }
 247
 248 static const TypeInfo qemu_s390_skeys_info = {
 249     .name          = TYPE_QEMU_S390_SKEYS,
 250     .parent        = TYPE_S390_SKEYS,
 251     .instance_init = qemu_s390_skeys_init,
 252     .instance_size = sizeof(QEMUS390SKeysState),
 253     .class_init    = qemu_s390_skeys_class_init,
 254     .class_size    = sizeof(S390SKeysClass),
 255 };
 256
 257 static void s390_storage_keys_save(QEMUFile *f, void *opaque)
 258 {
 259     S390SKeysState *ss = S390_SKEYS(opaque);
 260     S390SKeysClass *skeyclass = S390_SKEYS_GET_CLASS(ss);
 261     GuestPhysBlockList guest_phys_blocks;
 262     GuestPhysBlock *block;
 263     uint64_t pages, gfn;
 264     int error = 0;
 265     uint8_t *buf;
 266
 267     if (!skeyclass->skeys_enabled(ss)) {
 268         goto end_stream;
 269     }
 270
 271     buf = g_try_malloc(S390_SKEYS_BUFFER_SIZE);
 272     if (!buf) {
 273         error_report("storage key save could not allocate memory");
 274         goto end_stream;
 275     }
 276
 277     guest_phys_blocks_init(&guest_phys_blocks);
 278     guest_phys_blocks_append(&guest_phys_blocks);
 279
 280     /* Send each contiguous physical memory range separately. */
 281     QTAILQ_FOREACH(block, &guest_phys_blocks.head, next) {
 282         assert(QEMU_IS_ALIGNED(block->target_start, TARGET_PAGE_SIZE));
 283         assert(QEMU_IS_ALIGNED(block->target_end, TARGET_PAGE_SIZE));
 284
 285         gfn = block->target_start / TARGET_PAGE_SIZE;
 286         pages = (block->target_end - block->target_start) / TARGET_PAGE_SIZE;
 287         qemu_put_be64(f, block->target_start | S390_SKEYS_SAVE_FLAG_SKEYS);
 288         qemu_put_be64(f, pages);
 289
 290         while (pages) {
 291             const uint64_t cur_pages = MIN(pages, S390_SKEYS_BUFFER_SIZE);
 292
 293             if (!error) {
 294                 error = skeyclass->get_skeys(ss, gfn, cur_pages, buf);
 295                 if (error) {
 296                     /*
 297                      * Create a valid stream with all 0x00 and indicate
 298                      * S390_SKEYS_SAVE_FLAG_ERROR to the destination.
 299                      */
 300                     error_report("S390_GET_KEYS error %d", error);
 301                     memset(buf, 0, S390_SKEYS_BUFFER_SIZE);
 302                 }
 303             }
 304
 305             qemu_put_buffer(f, buf, cur_pages);
 306             gfn += cur_pages;
 307             pages -= cur_pages;
 308         }
 309
 310         if (error) {
 311             break;
 312         }
 313     }
 314
 315     guest_phys_blocks_free(&guest_phys_blocks);
 316     g_free(buf);
 317 end_stream:
 318     if (error) {
 319         qemu_put_be64(f, S390_SKEYS_SAVE_FLAG_ERROR);
 320     } else {
 321         qemu_put_be64(f, S390_SKEYS_SAVE_FLAG_EOS);
 322     }
 323 }
 324
 325 static int s390_storage_keys_load(QEMUFile *f, void *opaque, int version_id)
 326 {
 327     S390SKeysState *ss = S390_SKEYS(opaque);
 328     S390SKeysClass *skeyclass = S390_SKEYS_GET_CLASS(ss);
 329     int ret = 0;
 330
 331     while (!ret) {
 332         ram_addr_t addr;
 333         int flags;
 334
 335         addr = qemu_get_be64(f);
 336         flags = addr & ~TARGET_PAGE_MASK;
 337         addr &= TARGET_PAGE_MASK;
 338
 339         switch (flags) {
 340         case S390_SKEYS_SAVE_FLAG_SKEYS: {
 341             const uint64_t total_count = qemu_get_be64(f);
 342             uint64_t handled_count = 0, cur_count;
 343             uint64_t cur_gfn = addr / TARGET_PAGE_SIZE;
 344             uint8_t *buf = g_try_malloc(S390_SKEYS_BUFFER_SIZE);
 345
 346             if (!buf) {
 347                 error_report("storage key load could not allocate memory");
 348                 ret = -ENOMEM;
 349                 break;
 350             }
 351
 352             while (handled_count < total_count) {
 353                 cur_count = MIN(total_count - handled_count,
 354                                 S390_SKEYS_BUFFER_SIZE);
 355                 qemu_get_buffer(f, buf, cur_count);
 356
 357                 ret = skeyclass->set_skeys(ss, cur_gfn, cur_count, buf);
 358                 if (ret < 0) {
 359                     error_report("S390_SET_KEYS error %d", ret);
 360                     break;
 361                 }
 362                 handled_count += cur_count;
 363                 cur_gfn += cur_count;
 364             }
 365             g_free(buf);
 366             break;
 367         }
 368         case S390_SKEYS_SAVE_FLAG_ERROR: {
 369             error_report("Storage key data is incomplete");
 370             ret = -EINVAL;
 371             break;
 372         }
 373         case S390_SKEYS_SAVE_FLAG_EOS:
 374             /* normal exit */
 375             return 0;
 376         default:
 377             error_report("Unexpected storage key flag data: %#x", flags);
 378             ret = -EINVAL;
 379         }
 380     }
 381
 382     return ret;
 383 }
 384
 385 static inline bool s390_skeys_get_migration_enabled(Object *obj, Error **errp)
 386 {
 387     S390SKeysState *ss = S390_SKEYS(obj);
 388
 389     return ss->migration_enabled;
 390 }
 391
 392 static SaveVMHandlers savevm_s390_storage_keys = {
 393     .save_state = s390_storage_keys_save,
 394     .load_state = s390_storage_keys_load,
 395 };
 396
 397 static inline void s390_skeys_set_migration_enabled(Object *obj, bool value,
 398                                             Error **errp)
 399 {
 400     S390SKeysState *ss = S390_SKEYS(obj);
 401
 402     /* Prevent double registration of savevm handler */
 403     if (ss->migration_enabled == value) {
 404         return;
 405     }
 406
 407     ss->migration_enabled = value;
 408
 409     if (ss->migration_enabled) {
 410         register_savevm_live(TYPE_S390_SKEYS, 0, 1,
 411                              &savevm_s390_storage_keys, ss);
 412     } else {
 413         unregister_savevm(VMSTATE_IF(ss), TYPE_S390_SKEYS, ss);
 414     }
 415 }
 416
 417 static void s390_skeys_instance_init(Object *obj)
 418 {
 419     object_property_add_bool(obj, "migration-enabled",
 420                              s390_skeys_get_migration_enabled,
 421                              s390_skeys_set_migration_enabled);
 422     object_property_set_bool(obj, "migration-enabled", true, NULL);
 423 }
 424
 425 static void s390_skeys_class_init(ObjectClass *oc, void *data)
 426 {
 427     DeviceClass *dc = DEVICE_CLASS(oc);
 428
 429     dc->hotpluggable = false;
 430     set_bit(DEVICE_CATEGORY_MISC, dc->categories);
 431 }
 432
 433 static const TypeInfo s390_skeys_info = {
 434     .name          = TYPE_S390_SKEYS,
 435     .parent        = TYPE_DEVICE,
 436     .instance_init = s390_skeys_instance_init,
 437     .instance_size = sizeof(S390SKeysState),
 438     .class_init    = s390_skeys_class_init,
 439     .class_size    = sizeof(S390SKeysClass),
 440     .abstract = true,
 441 };
 442
 443 static void qemu_s390_skeys_register_types(void)
 444 {
 445     type_register_static(&s390_skeys_info);
 446     type_register_static(&qemu_s390_skeys_info);
 447 }
 448
 449 type_init(qemu_s390_skeys_register_types)