kernel/fs/zfs/zcp_iter.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 by Delphix. All rights reserved.
  18  */
  19
  20 #include "lua.h"
  21 #include "lauxlib.h"
  22
  23 #include <sys/dmu.h>
  24 #include <sys/dsl_prop.h>
  25 #include <sys/dsl_synctask.h>
  26 #include <sys/dsl_dataset.h>
  27 #include <sys/dsl_pool.h>
  28 #include <sys/dmu_tx.h>
  29 #include <sys/dmu_objset.h>
  30 #include <sys/zap.h>
  31 #include <sys/dsl_dir.h>
  32 #include <sys/zcp_prop.h>
  33
  34 #include <sys/zcp.h>
  35
  36 typedef int (zcp_list_func_t)(lua_State *);
  37 typedef struct zcp_list_info {
  38         const char *name;
  39         zcp_list_func_t *func;
  40         zcp_list_func_t *gc;
  41         const zcp_arg_t pargs[4];
  42         const zcp_arg_t kwargs[2];
  43 } zcp_list_info_t;
  44
  45 static int
  46 zcp_clones_iter(lua_State *state)
  47 {
  48         int err;
  49         char clonename[ZFS_MAX_DATASET_NAME_LEN];
  50         uint64_t dsobj = lua_tonumber(state, lua_upvalueindex(1));
  51         uint64_t cursor = lua_tonumber(state, lua_upvalueindex(2));
  52         dsl_pool_t *dp = zcp_run_info(state)->zri_pool;
  53         dsl_dataset_t *ds, *clone;
  54         zap_attribute_t za;
  55         zap_cursor_t zc;
  56
  57         err = dsl_dataset_hold_obj(dp, dsobj, FTAG, &ds);
  58         if (err == ENOENT) {
  59                 return (0);
  60         } else if (err != 0) {
  61                 return (luaL_error(state,
  62                     "unexpected error %d from dsl_dataset_hold_obj(dsobj)",
  63                     err));
  64         }
  65
  66         if (dsl_dataset_phys(ds)->ds_next_clones_obj == 0) {
  67                 dsl_dataset_rele(ds, FTAG);
  68                 return (0);
  69         }
  70
  71         zap_cursor_init_serialized(&zc, dp->dp_meta_objset,
  72             dsl_dataset_phys(ds)->ds_next_clones_obj, cursor);
  73         dsl_dataset_rele(ds, FTAG);
  74
  75         err = zap_cursor_retrieve(&zc, &za);
  76         if (err != 0) {
  77                 zap_cursor_fini(&zc);
  78                 if (err != ENOENT) {
  79                         return (luaL_error(state,
  80                             "unexpected error %d from zap_cursor_retrieve()",
  81                             err));
  82                 }
  83                 return (0);
  84         }
  85         zap_cursor_advance(&zc);
  86         cursor = zap_cursor_serialize(&zc);
  87         zap_cursor_fini(&zc);
  88
  89         err = dsl_dataset_hold_obj(dp, za.za_first_integer, FTAG, &clone);
  90         if (err != 0) {
  91                 return (luaL_error(state,
  92                     "unexpected error %d from "
  93                     "dsl_dataset_hold_obj(za_first_integer)", err));
  94         }
  95
  96         dsl_dir_name(clone->ds_dir, clonename);
  97         dsl_dataset_rele(clone, FTAG);
  98
  99         lua_pushnumber(state, cursor);
 100         lua_replace(state, lua_upvalueindex(2));
 101
 102         (void) lua_pushstring(state, clonename);
 103         return (1);
 104 }
 105
 106 static int zcp_clones_list(lua_State *);
 107 static zcp_list_info_t zcp_clones_list_info = {
 108         .name = "clones",
 109         .func = zcp_clones_list,
 110         .gc = NULL,
 111         .pargs = {
 112             { .za_name = "snapshot", .za_lua_type = LUA_TSTRING},
 113             {NULL, 0}
 114         },
 115         .kwargs = {
 116             {NULL, 0}
 117         }
 118 };
 119
 120 static int
 121 zcp_clones_list(lua_State *state)
 122 {
 123         const char *snapname = lua_tostring(state, 1);
 124         dsl_pool_t *dp = zcp_run_info(state)->zri_pool;
 125         boolean_t issnap;
 126         uint64_t dsobj, cursor;
 127
 128         /*
 129          * zcp_dataset_hold will either successfully return the requested
 130          * dataset or throw a lua error and longjmp out of the zfs.list.clones
 131          * call without returning.
 132          */
 133         dsl_dataset_t *ds = zcp_dataset_hold(state, dp, snapname, FTAG);
 134         if (ds == NULL)
 135                 return (1); /* not reached; zcp_dataset_hold() longjmp'd */
 136         cursor = 0;
 137         issnap = ds->ds_is_snapshot;
 138         dsobj = ds->ds_object;
 139         dsl_dataset_rele(ds, FTAG);
 140
 141         if (!issnap) {
 142                 return (zcp_argerror(state, 1, "%s is not a snapshot",
 143                     snapname));
 144         }
 145
 146         lua_pushnumber(state, dsobj);
 147         lua_pushnumber(state, cursor);
 148         lua_pushcclosure(state, &zcp_clones_iter, 2);
 149         return (1);
 150 }
 151
 152 static int
 153 zcp_snapshots_iter(lua_State *state)
 154 {
 155         int err;
 156         char snapname[ZFS_MAX_DATASET_NAME_LEN];
 157         uint64_t dsobj = lua_tonumber(state, lua_upvalueindex(1));
 158         uint64_t cursor = lua_tonumber(state, lua_upvalueindex(2));
 159         dsl_pool_t *dp = zcp_run_info(state)->zri_pool;
 160         dsl_dataset_t *ds;
 161         objset_t *os;
 162         char *p;
 163
 164         err = dsl_dataset_hold_obj(dp, dsobj, FTAG, &ds);
 165         if (err != 0) {
 166                 return (luaL_error(state,
 167                     "unexpected error %d from dsl_dataset_hold_obj(dsobj)",
 168                     err));
 169         }
 170
 171         dsl_dataset_name(ds, snapname);
 172         VERIFY3U(sizeof (snapname), >,
 173             strlcat(snapname, "@", sizeof (snapname)));
 174
 175         p = strchr(snapname, '\0');
 176         VERIFY0(dmu_objset_from_ds(ds, &os));
 177         err = dmu_snapshot_list_next(os,
 178             sizeof (snapname) - (p - snapname), p, NULL, &cursor, NULL);
 179         dsl_dataset_rele(ds, FTAG);
 180
 181         if (err == ENOENT) {
 182                 return (0);
 183         } else if (err != 0) {
 184                 return (luaL_error(state,
 185                     "unexpected error %d from dmu_snapshot_list_next()", err));
 186         }
 187
 188         lua_pushnumber(state, cursor);
 189         lua_replace(state, lua_upvalueindex(2));
 190
 191         (void) lua_pushstring(state, snapname);
 192         return (1);
 193 }
 194
 195 static int zcp_snapshots_list(lua_State *);
 196 static zcp_list_info_t zcp_snapshots_list_info = {
 197         .name = "snapshots",
 198         .func = zcp_snapshots_list,
 199         .gc = NULL,
 200         .pargs = {
 201             { .za_name = "filesystem | volume", .za_lua_type = LUA_TSTRING},
 202             {NULL, 0}
 203         },
 204         .kwargs = {
 205             {NULL, 0}
 206         }
 207 };
 208
 209 static int
 210 zcp_snapshots_list(lua_State *state)
 211 {
 212         const char *fsname = lua_tostring(state, 1);
 213         dsl_pool_t *dp = zcp_run_info(state)->zri_pool;
 214         boolean_t issnap;
 215         uint64_t dsobj;
 216
 217         dsl_dataset_t *ds = zcp_dataset_hold(state, dp, fsname, FTAG);
 218         if (ds == NULL)
 219                 return (1); /* not reached; zcp_dataset_hold() longjmp'd */
 220         issnap = ds->ds_is_snapshot;
 221         dsobj = ds->ds_object;
 222         dsl_dataset_rele(ds, FTAG);
 223
 224         if (issnap) {
 225                 return (zcp_argerror(state, 1,
 226                     "argument %s cannot be a snapshot", fsname));
 227         }
 228
 229         lua_pushnumber(state, dsobj);
 230         lua_pushnumber(state, 0);
 231         lua_pushcclosure(state, &zcp_snapshots_iter, 2);
 232         return (1);
 233 }
 234
 235 /*
 236  * Note: channel programs only run in the global zone, so all datasets
 237  * are visible to this zone.
 238  */
 239 static boolean_t
 240 dataset_name_hidden(const char *name)
 241 {
 242         if (strchr(name, '$') != NULL)
 243                 return (B_TRUE);
 244         if (strchr(name, '%') != NULL)
 245                 return (B_TRUE);
 246         return (B_FALSE);
 247 }
 248
 249 static int
 250 zcp_children_iter(lua_State *state)
 251 {
 252         int err;
 253         char childname[ZFS_MAX_DATASET_NAME_LEN];
 254         uint64_t dsobj = lua_tonumber(state, lua_upvalueindex(1));
 255         uint64_t cursor = lua_tonumber(state, lua_upvalueindex(2));
 256         zcp_run_info_t *ri = zcp_run_info(state);
 257         dsl_pool_t *dp = ri->zri_pool;
 258         dsl_dataset_t *ds;
 259         objset_t *os;
 260         char *p;
 261
 262         err = dsl_dataset_hold_obj(dp, dsobj, FTAG, &ds);
 263         if (err != 0) {
 264                 return (luaL_error(state,
 265                     "unexpected error %d from dsl_dataset_hold_obj(dsobj)",
 266                     err));
 267         }
 268
 269         dsl_dataset_name(ds, childname);
 270         VERIFY3U(sizeof (childname), >,
 271             strlcat(childname, "/", sizeof (childname)));
 272         p = strchr(childname, '\0');
 273
 274         VERIFY0(dmu_objset_from_ds(ds, &os));
 275         do {
 276                 err = dmu_dir_list_next(os,
 277                     sizeof (childname) - (p - childname), p, NULL, &cursor);
 278         } while (err == 0 && dataset_name_hidden(childname));
 279         dsl_dataset_rele(ds, FTAG);
 280
 281         if (err == ENOENT) {
 282                 return (0);
 283         } else if (err != 0) {
 284                 return (luaL_error(state,
 285                     "unexpected error %d from dmu_dir_list_next()",
 286                     err));
 287         }
 288
 289         lua_pushnumber(state, cursor);
 290         lua_replace(state, lua_upvalueindex(2));
 291
 292         (void) lua_pushstring(state, childname);
 293         return (1);
 294 }
 295
 296 static int zcp_children_list(lua_State *);
 297 static zcp_list_info_t zcp_children_list_info = {
 298         .name = "children",
 299         .func = zcp_children_list,
 300         .gc = NULL,
 301         .pargs = {
 302             { .za_name = "filesystem | volume", .za_lua_type = LUA_TSTRING},
 303             {NULL, 0}
 304         },
 305         .kwargs = {
 306             {NULL, 0}
 307         }
 308 };
 309
 310 static int
 311 zcp_children_list(lua_State *state)
 312 {
 313         const char *fsname = lua_tostring(state, 1);
 314         dsl_pool_t *dp = zcp_run_info(state)->zri_pool;
 315         boolean_t issnap;
 316         uint64_t dsobj;
 317
 318         dsl_dataset_t *ds = zcp_dataset_hold(state, dp, fsname, FTAG);
 319         if (ds == NULL)
 320                 return (1); /* not reached; zcp_dataset_hold() longjmp'd */
 321
 322         issnap = ds->ds_is_snapshot;
 323         dsobj = ds->ds_object;
 324         dsl_dataset_rele(ds, FTAG);
 325
 326         if (issnap) {
 327                 return (zcp_argerror(state, 1,
 328                     "argument %s cannot be a snapshot", fsname));
 329         }
 330
 331         lua_pushnumber(state, dsobj);
 332         lua_pushnumber(state, 0);
 333         lua_pushcclosure(state, &zcp_children_iter, 2);
 334         return (1);
 335 }
 336
 337 static int
 338 zcp_props_list_gc(lua_State *state)
 339 {
 340         nvlist_t **props = lua_touserdata(state, 1);
 341         if (*props != NULL)
 342                 fnvlist_free(*props);
 343         return (0);
 344 }
 345
 346 static int
 347 zcp_props_iter(lua_State *state)
 348 {
 349         char *source, *val;
 350         nvlist_t *nvprop;
 351         nvlist_t **props = lua_touserdata(state, lua_upvalueindex(1));
 352         nvpair_t *pair = lua_touserdata(state, lua_upvalueindex(2));
 353
 354         do {
 355                 pair = nvlist_next_nvpair(*props, pair);
 356                 if (pair == NULL) {
 357                         fnvlist_free(*props);
 358                         *props = NULL;
 359                         return (0);
 360                 }
 361         } while (!zfs_prop_user(nvpair_name(pair)));
 362
 363         lua_pushlightuserdata(state, pair);
 364         lua_replace(state, lua_upvalueindex(2));
 365
 366         nvprop = fnvpair_value_nvlist(pair);
 367         val = fnvlist_lookup_string(nvprop, ZPROP_VALUE);
 368         source = fnvlist_lookup_string(nvprop, ZPROP_SOURCE);
 369
 370         (void) lua_pushstring(state, nvpair_name(pair));
 371         (void) lua_pushstring(state, val);
 372         (void) lua_pushstring(state, source);
 373         return (3);
 374 }
 375
 376 static int zcp_props_list(lua_State *);
 377 static zcp_list_info_t zcp_props_list_info = {
 378         .name = "properties",
 379         .func = zcp_props_list,
 380         .gc = zcp_props_list_gc,
 381         .pargs = {
 382             { .za_name = "filesystem | snapshot | volume",
 383             .za_lua_type = LUA_TSTRING},
 384             {NULL, 0}
 385         },
 386         .kwargs = {
 387             {NULL, 0}
 388         }
 389 };
 390
 391 static int
 392 zcp_props_list(lua_State *state)
 393 {
 394         const char *dsname = lua_tostring(state, 1);
 395         dsl_pool_t *dp = zcp_run_info(state)->zri_pool;
 396         objset_t *os;
 397         nvlist_t **props = lua_newuserdata(state, sizeof (nvlist_t *));
 398
 399         dsl_dataset_t *ds = zcp_dataset_hold(state, dp, dsname, FTAG);
 400         if (ds == NULL)
 401                 return (1); /* not reached; zcp_dataset_hold() longjmp'd */
 402         VERIFY0(dmu_objset_from_ds(ds, &os));
 403         VERIFY0(dsl_prop_get_all(os, props));
 404         dsl_dataset_rele(ds, FTAG);
 405
 406         /*
 407          * Set the metatable for the properties list to free it on completion.
 408          */
 409         luaL_getmetatable(state, zcp_props_list_info.name);
 410         (void) lua_setmetatable(state, -2);
 411
 412         lua_pushlightuserdata(state, NULL);
 413         lua_pushcclosure(state, &zcp_props_iter, 2);
 414         return (1);
 415 }
 416
 417
 418 /*
 419  * Populate nv with all valid properties and their values for the given
 420  * dataset.
 421  */
 422 static void
 423 zcp_dataset_props(dsl_dataset_t *ds, nvlist_t *nv)
 424 {
 425         for (int prop = ZFS_PROP_TYPE; prop < ZFS_NUM_PROPS; prop++) {
 426                 /* Do not display hidden props */
 427                 if (!zfs_prop_visible(prop))
 428                         continue;
 429                 /* Do not display props not valid for this dataset */
 430                 if (!prop_valid_for_ds(ds, prop))
 431                         continue;
 432                 fnvlist_add_boolean(nv, zfs_prop_to_name(prop));
 433         }
 434 }
 435
 436 static int zcp_system_props_list(lua_State *);
 437 static zcp_list_info_t zcp_system_props_list_info = {
 438         .name = "system_properties",
 439         .func = zcp_system_props_list,
 440         .pargs = {
 441             { .za_name = "dataset", .za_lua_type = LUA_TSTRING},
 442             {NULL, 0}
 443         },
 444         .kwargs = {
 445             {NULL, 0}
 446         }
 447 };
 448
 449 /*
 450  * Get a list of all visble properties and their values for a given dataset.
 451  * Returned on the stack as a Lua table.
 452  */
 453 static int
 454 zcp_system_props_list(lua_State *state)
 455 {
 456         int error;
 457         char errbuf[128];
 458         const char *dataset_name;
 459         dsl_pool_t *dp = zcp_run_info(state)->zri_pool;
 460         zcp_list_info_t *libinfo = &zcp_system_props_list_info;
 461         zcp_parse_args(state, libinfo->name, libinfo->pargs, libinfo->kwargs);
 462         dataset_name = lua_tostring(state, 1);
 463         nvlist_t *nv = fnvlist_alloc();
 464
 465         dsl_dataset_t *ds = zcp_dataset_hold(state, dp, dataset_name, FTAG);
 466         if (ds == NULL)
 467                 return (1); /* not reached; zcp_dataset_hold() longjmp'd */
 468
 469         /* Get the names of all valid properties for this dataset */
 470         zcp_dataset_props(ds, nv);
 471         dsl_dataset_rele(ds, FTAG);
 472
 473         /* push list as lua table */
 474         error = zcp_nvlist_to_lua(state, nv, errbuf, sizeof (errbuf));
 475         nvlist_free(nv);
 476         if (error != 0) {
 477                 return (luaL_error(state,
 478                     "Error returning nvlist: %s", errbuf));
 479         }
 480         return (1);
 481 }
 482
 483 static int
 484 zcp_list_func(lua_State *state)
 485 {
 486         zcp_list_info_t *info = lua_touserdata(state, lua_upvalueindex(1));
 487
 488         zcp_parse_args(state, info->name, info->pargs, info->kwargs);
 489
 490         return (info->func(state));
 491 }
 492
 493 int
 494 zcp_load_list_lib(lua_State *state)
 495 {
 496         int i;
 497         zcp_list_info_t *zcp_list_funcs[] = {
 498                 &zcp_children_list_info,
 499                 &zcp_snapshots_list_info,
 500                 &zcp_props_list_info,
 501                 &zcp_clones_list_info,
 502                 &zcp_system_props_list_info,
 503                 NULL
 504         };
 505
 506         lua_newtable(state);
 507
 508         for (i = 0; zcp_list_funcs[i] != NULL; i++) {
 509                 zcp_list_info_t *info = zcp_list_funcs[i];
 510
 511                 if (info->gc != NULL) {
 512                         /*
 513                          * If the function requires garbage collection, create
 514                          * a metatable with its name and register the __gc
 515                          * function.
 516                          */
 517                         (void) luaL_newmetatable(state, info->name);
 518                         (void) lua_pushstring(state, "__gc");
 519                         lua_pushcfunction(state, info->gc);
 520                         lua_settable(state, -3);
 521                         lua_pop(state, 1);
 522                 }
 523
 524                 lua_pushlightuserdata(state, info);
 525                 lua_pushcclosure(state, &zcp_list_func, 1);
 526                 lua_setfield(state, -2, info->name);
 527                 info++;
 528         }
 529
 530         return (1);
 531 }