module/zfs/zcp_synctask.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * This file and its contents are supplied under the terms of the
   5  * Common Development and Distribution License ("CDDL"), version 1.0.
   6  * You may only use this file in accordance with the terms of version
   7  * 1.0 of the CDDL.
   8  *
   9  * A full copy of the text of the CDDL should have accompanied this
  10  * source.  A copy of the CDDL is also available via the Internet at
  11  * http://www.illumos.org/license/CDDL.
  12  *
  13  * CDDL HEADER END
  14  */
  15
  16 /*
  17  * Copyright (c) 2016, 2017 by Delphix. All rights reserved.
  18  * Copyright (c) 2019, 2020 by Christian Schwarz. All rights reserved.
  19  * Copyright 2020 Joyent, Inc.
  20  */
  21
  22 #include <sys/lua/lua.h>
  23 #include <sys/lua/lauxlib.h>
  24
  25 #include <sys/zcp.h>
  26 #include <sys/zcp_set.h>
  27 #include <sys/dsl_dir.h>
  28 #include <sys/dsl_pool.h>
  29 #include <sys/dsl_prop.h>
  30 #include <sys/dsl_synctask.h>
  31 #include <sys/dsl_dataset.h>
  32 #include <sys/dsl_bookmark.h>
  33 #include <sys/dsl_destroy.h>
  34 #include <sys/dmu_objset.h>
  35 #include <sys/zfs_znode.h>
  36 #include <sys/zfeature.h>
  37 #include <sys/metaslab.h>
  38
  39 #define DST_AVG_BLKSHIFT 14
  40
  41 typedef struct zcp_inherit_prop_arg {
  42         lua_State               *zipa_state;
  43         const char              *zipa_prop;
  44         dsl_props_set_arg_t     zipa_dpsa;
  45 } zcp_inherit_prop_arg_t;
  46
  47 typedef int (zcp_synctask_func_t)(lua_State *, boolean_t, nvlist_t *);
  48 typedef struct zcp_synctask_info {
  49         const char *name;
  50         zcp_synctask_func_t *func;
  51         const zcp_arg_t pargs[4];
  52         const zcp_arg_t kwargs[2];
  53         zfs_space_check_t space_check;
  54         int blocks_modified;
  55 } zcp_synctask_info_t;
  56
  57 static void
  58 zcp_synctask_cleanup(void *arg)
  59 {
  60         fnvlist_free(arg);
  61 }
  62
  63 /*
  64  * Generic synctask interface for channel program syncfuncs.
  65  *
  66  * To perform some action in syncing context, we'd generally call
  67  * dsl_sync_task(), but since the Lua script is already running inside a
  68  * synctask we need to leave out some actions (such as acquiring the config
  69  * rwlock and performing space checks).
  70  *
  71  * If 'sync' is false, executes a dry run and returns the error code.
  72  *
  73  * If we are not running in syncing context and we are not doing a dry run
  74  * (meaning we are running a zfs.sync function in open-context) then we
  75  * return a Lua error.
  76  *
  77  * This function also handles common fatal error cases for channel program
  78  * library functions. If a fatal error occurs, err_dsname will be the dataset
  79  * name reported in error messages, if supplied.
  80  */
  81 static int
  82 zcp_sync_task(lua_State *state, dsl_checkfunc_t *checkfunc,
  83     dsl_syncfunc_t *syncfunc, void *arg, boolean_t sync, const char *err_dsname)
  84 {
  85         int err;
  86         zcp_run_info_t *ri = zcp_run_info(state);
  87
  88         err = checkfunc(arg, ri->zri_tx);
  89         if (!sync)
  90                 return (err);
  91
  92         if (!ri->zri_sync) {
  93                 return (luaL_error(state, "running functions from the zfs.sync "
  94                     "submodule requires passing sync=TRUE to "
  95                     "lzc_channel_program() (i.e. do not specify the \"-n\" "
  96                     "command line argument)"));
  97         }
  98
  99         if (err == 0) {
 100                 syncfunc(arg, ri->zri_tx);
 101         } else if (err == EIO) {
 102                 if (err_dsname != NULL) {
 103                         return (luaL_error(state,
 104                             "I/O error while accessing dataset '%s'",
 105                             err_dsname));
 106                 } else {
 107                         return (luaL_error(state,
 108                             "I/O error while accessing dataset."));
 109                 }
 110         }
 111
 112         return (err);
 113 }
 114
 115
 116 static int zcp_synctask_destroy(lua_State *, boolean_t, nvlist_t *);
 117 static const zcp_synctask_info_t zcp_synctask_destroy_info = {
 118         .name = "destroy",
 119         .func = zcp_synctask_destroy,
 120         .pargs = {
 121             {.za_name = "filesystem | snapshot", .za_lua_type = LUA_TSTRING },
 122             {NULL, 0}
 123         },
 124         .kwargs = {
 125             {.za_name = "defer", .za_lua_type = LUA_TBOOLEAN },
 126             {NULL, 0}
 127         },
 128         .space_check = ZFS_SPACE_CHECK_DESTROY,
 129         .blocks_modified = 0
 130 };
 131
 132 static int
 133 zcp_synctask_destroy(lua_State *state, boolean_t sync, nvlist_t *err_details)
 134 {
 135         (void) err_details;
 136         int err;
 137         const char *dsname = lua_tostring(state, 1);
 138
 139         boolean_t issnap = (strchr(dsname, '@') != NULL);
 140
 141         if (!issnap && !lua_isnil(state, 2)) {
 142                 return (luaL_error(state,
 143                     "'deferred' kwarg only supported for snapshots: %s",
 144                     dsname));
 145         }
 146
 147         if (issnap) {
 148                 dsl_destroy_snapshot_arg_t ddsa = { 0 };
 149                 ddsa.ddsa_name = dsname;
 150                 if (!lua_isnil(state, 2)) {
 151                         ddsa.ddsa_defer = lua_toboolean(state, 2);
 152                 } else {
 153                         ddsa.ddsa_defer = B_FALSE;
 154                 }
 155
 156                 err = zcp_sync_task(state, dsl_destroy_snapshot_check,
 157                     dsl_destroy_snapshot_sync, &ddsa, sync, dsname);
 158         } else {
 159                 dsl_destroy_head_arg_t ddha = { 0 };
 160                 ddha.ddha_name = dsname;
 161
 162                 err = zcp_sync_task(state, dsl_destroy_head_check,
 163                     dsl_destroy_head_sync, &ddha, sync, dsname);
 164         }
 165
 166         return (err);
 167 }
 168
 169 static int zcp_synctask_promote(lua_State *, boolean_t, nvlist_t *);
 170 static const zcp_synctask_info_t zcp_synctask_promote_info = {
 171         .name = "promote",
 172         .func = zcp_synctask_promote,
 173         .pargs = {
 174             {.za_name = "clone", .za_lua_type = LUA_TSTRING },
 175             {NULL, 0}
 176         },
 177         .kwargs = {
 178             {NULL, 0}
 179         },
 180         .space_check = ZFS_SPACE_CHECK_RESERVED,
 181         .blocks_modified = 3
 182 };
 183
 184 static int
 185 zcp_synctask_promote(lua_State *state, boolean_t sync, nvlist_t *err_details)
 186 {
 187         int err;
 188         dsl_dataset_promote_arg_t ddpa = { 0 };
 189         const char *dsname = lua_tostring(state, 1);
 190         zcp_run_info_t *ri = zcp_run_info(state);
 191
 192         ddpa.ddpa_clonename = dsname;
 193         ddpa.err_ds = err_details;
 194         ddpa.cr = ri->zri_cred;
 195         ddpa.proc = ri->zri_proc;
 196
 197         /*
 198          * If there was a snapshot name conflict, then err_ds will be filled
 199          * with a list of conflicting snapshot names.
 200          */
 201         err = zcp_sync_task(state, dsl_dataset_promote_check,
 202             dsl_dataset_promote_sync, &ddpa, sync, dsname);
 203
 204         return (err);
 205 }
 206
 207 static int zcp_synctask_rollback(lua_State *, boolean_t, nvlist_t *err_details);
 208 static const zcp_synctask_info_t zcp_synctask_rollback_info = {
 209         .name = "rollback",
 210         .func = zcp_synctask_rollback,
 211         .space_check = ZFS_SPACE_CHECK_RESERVED,
 212         .blocks_modified = 1,
 213         .pargs = {
 214             {.za_name = "filesystem", .za_lua_type = LUA_TSTRING },
 215             {0, 0}
 216         },
 217         .kwargs = {
 218             {0, 0}
 219         }
 220 };
 221
 222 static int
 223 zcp_synctask_rollback(lua_State *state, boolean_t sync, nvlist_t *err_details)
 224 {
 225         int err;
 226         const char *dsname = lua_tostring(state, 1);
 227         dsl_dataset_rollback_arg_t ddra = { 0 };
 228
 229         ddra.ddra_fsname = dsname;
 230         ddra.ddra_result = err_details;
 231
 232         err = zcp_sync_task(state, dsl_dataset_rollback_check,
 233             dsl_dataset_rollback_sync, &ddra, sync, dsname);
 234
 235         return (err);
 236 }
 237
 238 static int zcp_synctask_snapshot(lua_State *, boolean_t, nvlist_t *);
 239 static const zcp_synctask_info_t zcp_synctask_snapshot_info = {
 240         .name = "snapshot",
 241         .func = zcp_synctask_snapshot,
 242         .pargs = {
 243             {.za_name = "filesystem@snapname | volume@snapname",
 244             .za_lua_type = LUA_TSTRING },
 245             {NULL, 0}
 246         },
 247         .kwargs = {
 248             {NULL, 0}
 249         },
 250         .space_check = ZFS_SPACE_CHECK_NORMAL,
 251         .blocks_modified = 3
 252 };
 253
 254 static int
 255 zcp_synctask_snapshot(lua_State *state, boolean_t sync, nvlist_t *err_details)
 256 {
 257         (void) err_details;
 258         int err;
 259         dsl_dataset_snapshot_arg_t ddsa = { 0 };
 260         const char *dsname = lua_tostring(state, 1);
 261         zcp_run_info_t *ri = zcp_run_info(state);
 262
 263         /*
 264          * On old pools, the ZIL must not be active when a snapshot is created,
 265          * but we can't suspend the ZIL because we're already in syncing
 266          * context.
 267          */
 268         if (spa_version(ri->zri_pool->dp_spa) < SPA_VERSION_FAST_SNAP) {
 269                 return (SET_ERROR(ENOTSUP));
 270         }
 271
 272         /*
 273          * We only allow for a single snapshot rather than a list, so the
 274          * error list output is unnecessary.
 275          */
 276         ddsa.ddsa_errors = NULL;
 277         ddsa.ddsa_props = NULL;
 278         ddsa.ddsa_cr = ri->zri_cred;
 279         ddsa.ddsa_proc = ri->zri_proc;
 280         ddsa.ddsa_snaps = fnvlist_alloc();
 281         fnvlist_add_boolean(ddsa.ddsa_snaps, dsname);
 282
 283         zcp_cleanup_handler_t *zch = zcp_register_cleanup(state,
 284             zcp_synctask_cleanup, ddsa.ddsa_snaps);
 285
 286         err = zcp_sync_task(state, dsl_dataset_snapshot_check,
 287             dsl_dataset_snapshot_sync, &ddsa, sync, dsname);
 288
 289         if (err == 0) {
 290                 /*
 291                  * We may need to create a new device minor node for this
 292                  * dataset (if it is a zvol and the "snapdev" property is set).
 293                  * Save it in the nvlist so that it can be processed in open
 294                  * context.
 295                  */
 296                 fnvlist_add_boolean(ri->zri_new_zvols, dsname);
 297         }
 298
 299         zcp_deregister_cleanup(state, zch);
 300         fnvlist_free(ddsa.ddsa_snaps);
 301
 302         return (err);
 303 }
 304
 305 static int zcp_synctask_inherit_prop(lua_State *, boolean_t,
 306     nvlist_t *err_details);
 307 static const zcp_synctask_info_t zcp_synctask_inherit_prop_info = {
 308         .name = "inherit",
 309         .func = zcp_synctask_inherit_prop,
 310         .space_check = ZFS_SPACE_CHECK_RESERVED,
 311         .blocks_modified = 2, /* 2 * numprops */
 312         .pargs = {
 313                 { .za_name = "dataset", .za_lua_type = LUA_TSTRING },
 314                 { .za_name = "property", .za_lua_type = LUA_TSTRING },
 315                 { NULL, 0 }
 316         },
 317         .kwargs = {
 318                 { NULL, 0 }
 319         },
 320 };
 321
 322 static int
 323 zcp_synctask_inherit_prop_check(void *arg, dmu_tx_t *tx)
 324 {
 325         zcp_inherit_prop_arg_t *args = arg;
 326         zfs_prop_t prop = zfs_name_to_prop(args->zipa_prop);
 327
 328         if (prop == ZPROP_INVAL) {
 329                 if (zfs_prop_user(args->zipa_prop))
 330                         return (0);
 331
 332                 return (EINVAL);
 333         }
 334
 335         if (zfs_prop_readonly(prop))
 336                 return (EINVAL);
 337
 338         if (!zfs_prop_inheritable(prop))
 339                 return (EINVAL);
 340
 341         return (dsl_props_set_check(&args->zipa_dpsa, tx));
 342 }
 343
 344 static void
 345 zcp_synctask_inherit_prop_sync(void *arg, dmu_tx_t *tx)
 346 {
 347         zcp_inherit_prop_arg_t *args = arg;
 348         dsl_props_set_arg_t *dpsa = &args->zipa_dpsa;
 349
 350         dsl_props_set_sync(dpsa, tx);
 351 }
 352
 353 static int
 354 zcp_synctask_inherit_prop(lua_State *state, boolean_t sync,
 355     nvlist_t *err_details)
 356 {
 357         (void) err_details;
 358         int err;
 359         zcp_inherit_prop_arg_t zipa = { 0 };
 360         dsl_props_set_arg_t *dpsa = &zipa.zipa_dpsa;
 361
 362         const char *dsname = lua_tostring(state, 1);
 363         const char *prop = lua_tostring(state, 2);
 364
 365         zipa.zipa_state = state;
 366         zipa.zipa_prop = prop;
 367         dpsa->dpsa_dsname = dsname;
 368         dpsa->dpsa_source = ZPROP_SRC_INHERITED;
 369         dpsa->dpsa_props = fnvlist_alloc();
 370         fnvlist_add_boolean(dpsa->dpsa_props, prop);
 371
 372         zcp_cleanup_handler_t *zch = zcp_register_cleanup(state,
 373             zcp_synctask_cleanup, dpsa->dpsa_props);
 374
 375         err = zcp_sync_task(state, zcp_synctask_inherit_prop_check,
 376             zcp_synctask_inherit_prop_sync, &zipa, sync, dsname);
 377
 378         zcp_deregister_cleanup(state, zch);
 379         fnvlist_free(dpsa->dpsa_props);
 380
 381         return (err);
 382 }
 383
 384 static int zcp_synctask_bookmark(lua_State *, boolean_t, nvlist_t *);
 385 static const zcp_synctask_info_t zcp_synctask_bookmark_info = {
 386         .name = "bookmark",
 387         .func = zcp_synctask_bookmark,
 388         .pargs = {
 389             {.za_name = "snapshot | bookmark", .za_lua_type = LUA_TSTRING },
 390             {.za_name = "bookmark", .za_lua_type = LUA_TSTRING },
 391             {NULL, 0}
 392         },
 393         .kwargs = {
 394             {NULL, 0}
 395         },
 396         .space_check = ZFS_SPACE_CHECK_NORMAL,
 397         .blocks_modified = 1,
 398 };
 399
 400 static int
 401 zcp_synctask_bookmark(lua_State *state, boolean_t sync, nvlist_t *err_details)
 402 {
 403         (void) err_details;
 404         int err;
 405         const char *source = lua_tostring(state, 1);
 406         const char *new = lua_tostring(state, 2);
 407
 408         nvlist_t *bmarks = fnvlist_alloc();
 409         fnvlist_add_string(bmarks, new, source);
 410
 411         zcp_cleanup_handler_t *zch = zcp_register_cleanup(state,
 412             zcp_synctask_cleanup, bmarks);
 413
 414         dsl_bookmark_create_arg_t dbca = {
 415                 .dbca_bmarks = bmarks,
 416                 .dbca_errors = NULL,
 417         };
 418         err = zcp_sync_task(state, dsl_bookmark_create_check,
 419             dsl_bookmark_create_sync, &dbca, sync, source);
 420
 421         zcp_deregister_cleanup(state, zch);
 422         fnvlist_free(bmarks);
 423
 424         return (err);
 425 }
 426
 427 static int zcp_synctask_set_prop(lua_State *, boolean_t, nvlist_t *err_details);
 428 static const zcp_synctask_info_t zcp_synctask_set_prop_info = {
 429         .name = "set_prop",
 430         .func = zcp_synctask_set_prop,
 431         .space_check = ZFS_SPACE_CHECK_RESERVED,
 432         .blocks_modified = 2,
 433         .pargs = {
 434                 { .za_name = "dataset", .za_lua_type = LUA_TSTRING },
 435                 { .za_name = "property", .za_lua_type =  LUA_TSTRING },
 436                 { .za_name = "value", .za_lua_type =  LUA_TSTRING },
 437                 { NULL, 0 }
 438         },
 439         .kwargs = {
 440                 { NULL, 0 }
 441         }
 442 };
 443
 444 static int
 445 zcp_synctask_set_prop(lua_State *state, boolean_t sync, nvlist_t *err_details)
 446 {
 447         (void) err_details;
 448         int err;
 449         zcp_set_prop_arg_t args = { 0 };
 450
 451         const char *dsname = lua_tostring(state, 1);
 452         const char *prop = lua_tostring(state, 2);
 453         const char *val = lua_tostring(state, 3);
 454
 455         args.state = state;
 456         args.dsname = dsname;
 457         args.prop = prop;
 458         args.val = val;
 459
 460         err = zcp_sync_task(state, zcp_set_prop_check, zcp_set_prop_sync,
 461             &args, sync, dsname);
 462
 463         return (err);
 464 }
 465
 466 static int
 467 zcp_synctask_wrapper(lua_State *state)
 468 {
 469         int err;
 470         zcp_cleanup_handler_t *zch;
 471         int num_ret = 1;
 472         nvlist_t *err_details = fnvlist_alloc();
 473
 474         /*
 475          * Make sure err_details is properly freed, even if a fatal error is
 476          * thrown during the synctask.
 477          */
 478         zch = zcp_register_cleanup(state, zcp_synctask_cleanup, err_details);
 479
 480         zcp_synctask_info_t *info = lua_touserdata(state, lua_upvalueindex(1));
 481         boolean_t sync = lua_toboolean(state, lua_upvalueindex(2));
 482
 483         zcp_run_info_t *ri = zcp_run_info(state);
 484         dsl_pool_t *dp = ri->zri_pool;
 485
 486         /* MOS space is triple-dittoed, so we multiply by 3. */
 487         uint64_t funcspace =
 488             ((uint64_t)info->blocks_modified << DST_AVG_BLKSHIFT) * 3;
 489
 490         zcp_parse_args(state, info->name, info->pargs, info->kwargs);
 491
 492         err = 0;
 493         if (info->space_check != ZFS_SPACE_CHECK_NONE) {
 494                 uint64_t quota = dsl_pool_unreserved_space(dp,
 495                     info->space_check);
 496                 uint64_t used = dsl_dir_phys(dp->dp_root_dir)->dd_used_bytes +
 497                     ri->zri_space_used;
 498
 499                 if (used + funcspace > quota) {
 500                         err = SET_ERROR(ENOSPC);
 501                 }
 502         }
 503
 504         if (err == 0) {
 505                 err = info->func(state, sync, err_details);
 506         }
 507
 508         if (err == 0) {
 509                 ri->zri_space_used += funcspace;
 510         }
 511
 512         lua_pushnumber(state, (lua_Number)err);
 513         if (fnvlist_num_pairs(err_details) > 0) {
 514                 (void) zcp_nvlist_to_lua(state, err_details, NULL, 0);
 515                 num_ret++;
 516         }
 517
 518         zcp_deregister_cleanup(state, zch);
 519         fnvlist_free(err_details);
 520
 521         return (num_ret);
 522 }
 523
 524 int
 525 zcp_load_synctask_lib(lua_State *state, boolean_t sync)
 526 {
 527         const zcp_synctask_info_t *zcp_synctask_funcs[] = {
 528                 &zcp_synctask_destroy_info,
 529                 &zcp_synctask_promote_info,
 530                 &zcp_synctask_rollback_info,
 531                 &zcp_synctask_snapshot_info,
 532                 &zcp_synctask_inherit_prop_info,
 533                 &zcp_synctask_bookmark_info,
 534                 &zcp_synctask_set_prop_info,
 535                 NULL
 536         };
 537
 538         lua_newtable(state);
 539
 540         for (int i = 0; zcp_synctask_funcs[i] != NULL; i++) {
 541                 const zcp_synctask_info_t *info = zcp_synctask_funcs[i];
 542                 lua_pushlightuserdata(state, (void *)(uintptr_t)info);
 543                 lua_pushboolean(state, sync);
 544                 lua_pushcclosure(state, &zcp_synctask_wrapper, 2);
 545                 lua_setfield(state, -2, info->name);
 546         }
 547
 548         return (1);
 549 }