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 */ 19 20 #include "lua.h" 21 #include "lauxlib.h" 22 23 #include <sys/zcp.h> 24 #include <sys/dsl_dir.h> 25 #include <sys/dsl_pool.h> 26 #include <sys/dsl_prop.h> 27 #include <sys/dsl_synctask.h> 28 #include <sys/dsl_dataset.h> 29 #include <sys/dsl_bookmark.h> 30 #include <sys/dsl_destroy.h> 31 #include <sys/dmu_objset.h> 32 #include <sys/zfs_znode.h> 33 #include <sys/zfeature.h> 34 #include <sys/metaslab.h> 35 36 #define DST_AVG_BLKSHIFT 14 37 38 typedef int (zcp_synctask_func_t)(lua_State *, boolean_t, nvlist_t *); 39 typedef struct zcp_synctask_info { 40 const char *name; 41 zcp_synctask_func_t *func; 42 const zcp_arg_t pargs[4]; 43 const zcp_arg_t kwargs[2]; 44 zfs_space_check_t space_check; 45 int blocks_modified; 46 } zcp_synctask_info_t; 47 48 /* 49 * Generic synctask interface for channel program syncfuncs. 50 * 51 * To perform some action in syncing context, we'd generally call 52 * dsl_sync_task(), but since the Lua script is already running inside a 53 * synctask we need to leave out some actions (such as acquiring the config 54 * rwlock and performing space checks). 55 * 56 * If 'sync' is false, executes a dry run and returns the error code. 57 * 58 * If we are not running in syncing context and we are not doing a dry run 59 * (meaning we are running a zfs.sync function in open-context) then we 60 * return a Lua error. 61 * 62 * This function also handles common fatal error cases for channel program 63 * library functions. If a fatal error occurs, err_dsname will be the dataset 64 * name reported in error messages, if supplied. 65 */ 66 static int 67 zcp_sync_task(lua_State *state, dsl_checkfunc_t *checkfunc, 68 dsl_syncfunc_t *syncfunc, void *arg, boolean_t sync, const char *err_dsname) 69 { 70 int err; 71 zcp_run_info_t *ri = zcp_run_info(state); 72 73 err = checkfunc(arg, ri->zri_tx); 74 if (!sync) 75 return (err); 76 77 if (!ri->zri_sync) { 78 return (luaL_error(state, "running functions from the zfs.sync " 79 "submodule requires passing sync=TRUE to " 80 "lzc_channel_program() (i.e. do not specify the \"-n\" " 81 "command line argument)")); 82 } 83 84 if (err == 0) { 85 syncfunc(arg, ri->zri_tx); 86 } else if (err == EIO) { 87 if (err_dsname != NULL) { 88 return (luaL_error(state, 89 "I/O error while accessing dataset '%s'", 90 err_dsname)); 91 } else { 92 return (luaL_error(state, 93 "I/O error while accessing dataset.")); 94 } 95 } 96 97 return (err); 98 } 99 100 101 static int zcp_synctask_destroy(lua_State *, boolean_t, nvlist_t *); 102 static zcp_synctask_info_t zcp_synctask_destroy_info = { 103 .name = "destroy", 104 .func = zcp_synctask_destroy, 105 .pargs = { 106 {.za_name = "filesystem | snapshot", .za_lua_type = LUA_TSTRING}, 107 {NULL, NULL} 108 }, 109 .kwargs = { 110 {.za_name = "defer", .za_lua_type = LUA_TBOOLEAN}, 111 {NULL, NULL} 112 }, 113 .space_check = ZFS_SPACE_CHECK_DESTROY, 114 .blocks_modified = 0 115 }; 116 117 /* ARGSUSED */ 118 static int 119 zcp_synctask_destroy(lua_State *state, boolean_t sync, nvlist_t *err_details) 120 { 121 int err; 122 const char *dsname = lua_tostring(state, 1); 123 124 boolean_t issnap = (strchr(dsname, '@') != NULL); 125 126 if (!issnap && !lua_isnil(state, 2)) { 127 return (luaL_error(state, 128 "'deferred' kwarg only supported for snapshots: %s", 129 dsname)); 130 } 131 132 if (issnap) { 133 dsl_destroy_snapshot_arg_t ddsa = { 0 }; 134 ddsa.ddsa_name = dsname; 135 if (!lua_isnil(state, 2)) { 136 ddsa.ddsa_defer = lua_toboolean(state, 2); 137 } else { 138 ddsa.ddsa_defer = B_FALSE; 139 } 140 141 err = zcp_sync_task(state, dsl_destroy_snapshot_check, 142 dsl_destroy_snapshot_sync, &ddsa, sync, dsname); 143 } else { 144 dsl_destroy_head_arg_t ddha = { 0 }; 145 ddha.ddha_name = dsname; 146 147 err = zcp_sync_task(state, dsl_destroy_head_check, 148 dsl_destroy_head_sync, &ddha, sync, dsname); 149 } 150 151 return (err); 152 } 153 154 static int zcp_synctask_promote(lua_State *, boolean_t, nvlist_t *); 155 static zcp_synctask_info_t zcp_synctask_promote_info = { 156 .name = "promote", 157 .func = zcp_synctask_promote, 158 .pargs = { 159 {.za_name = "clone", .za_lua_type = LUA_TSTRING}, 160 {NULL, NULL} 161 }, 162 .kwargs = { 163 {NULL, NULL} 164 }, 165 .space_check = ZFS_SPACE_CHECK_RESERVED, 166 .blocks_modified = 3 167 }; 168 169 static int 170 zcp_synctask_promote(lua_State *state, boolean_t sync, nvlist_t *err_details) 171 { 172 int err; 173 dsl_dataset_promote_arg_t ddpa = { 0 }; 174 const char *dsname = lua_tostring(state, 1); 175 zcp_run_info_t *ri = zcp_run_info(state); 176 177 ddpa.ddpa_clonename = dsname; 178 ddpa.err_ds = err_details; 179 ddpa.cr = ri->zri_cred; 180 181 /* 182 * If there was a snapshot name conflict, then err_ds will be filled 183 * with a list of conflicting snapshot names. 184 */ 185 err = zcp_sync_task(state, dsl_dataset_promote_check, 186 dsl_dataset_promote_sync, &ddpa, sync, dsname); 187 188 return (err); 189 } 190 191 static int zcp_synctask_rollback(lua_State *, boolean_t, nvlist_t *err_details); 192 static zcp_synctask_info_t zcp_synctask_rollback_info = { 193 .name = "rollback", 194 .func = zcp_synctask_rollback, 195 .space_check = ZFS_SPACE_CHECK_RESERVED, 196 .blocks_modified = 1, 197 .pargs = { 198 {.za_name = "filesystem", .za_lua_type = LUA_TSTRING}, 199 {NULL, NULL} 200 }, 201 .kwargs = { 202 {NULL, NULL} 203 } 204 }; 205 206 static int 207 zcp_synctask_rollback(lua_State *state, boolean_t sync, nvlist_t *err_details) 208 { 209 int err; 210 const char *dsname = lua_tostring(state, 1); 211 dsl_dataset_rollback_arg_t ddra = { 0 }; 212 213 ddra.ddra_fsname = dsname; 214 ddra.ddra_result = err_details; 215 216 err = zcp_sync_task(state, dsl_dataset_rollback_check, 217 dsl_dataset_rollback_sync, &ddra, sync, dsname); 218 219 return (err); 220 } 221 222 static int zcp_synctask_snapshot(lua_State *, boolean_t, nvlist_t *); 223 static zcp_synctask_info_t zcp_synctask_snapshot_info = { 224 .name = "snapshot", 225 .func = zcp_synctask_snapshot, 226 .pargs = { 227 {.za_name = "filesystem@snapname | volume@snapname", 228 .za_lua_type = LUA_TSTRING}, 229 {NULL, NULL} 230 }, 231 .kwargs = { 232 {NULL, NULL} 233 }, 234 .space_check = ZFS_SPACE_CHECK_NORMAL, 235 .blocks_modified = 3 236 }; 237 238 /* ARGSUSED */ 239 static int 240 zcp_synctask_snapshot(lua_State *state, boolean_t sync, nvlist_t *err_details) 241 { 242 int err; 243 dsl_dataset_snapshot_arg_t ddsa = { 0 }; 244 const char *dsname = lua_tostring(state, 1); 245 zcp_run_info_t *ri = zcp_run_info(state); 246 247 /* 248 * On old pools, the ZIL must not be active when a snapshot is created, 249 * but we can't suspend the ZIL because we're already in syncing 250 * context. 251 */ 252 if (spa_version(ri->zri_pool->dp_spa) < SPA_VERSION_FAST_SNAP) { 253 return (ENOTSUP); 254 } 255 256 /* 257 * We only allow for a single snapshot rather than a list, so the 258 * error list output is unnecessary. 259 */ 260 ddsa.ddsa_errors = NULL; 261 ddsa.ddsa_props = NULL; 262 ddsa.ddsa_cr = ri->zri_cred; 263 ddsa.ddsa_snaps = fnvlist_alloc(); 264 fnvlist_add_boolean(ddsa.ddsa_snaps, dsname); 265 266 zcp_cleanup_handler_t *zch = zcp_register_cleanup(state, 267 (zcp_cleanup_t *)&fnvlist_free, ddsa.ddsa_snaps); 268 269 err = zcp_sync_task(state, dsl_dataset_snapshot_check, 270 dsl_dataset_snapshot_sync, &ddsa, sync, dsname); 271 272 zcp_deregister_cleanup(state, zch); 273 fnvlist_free(ddsa.ddsa_snaps); 274 275 return (err); 276 } 277 278 static int 279 zcp_synctask_wrapper(lua_State *state) 280 { 281 int err; 282 zcp_cleanup_handler_t *zch; 283 int num_ret = 1; 284 nvlist_t *err_details = fnvlist_alloc(); 285 286 /* 287 * Make sure err_details is properly freed, even if a fatal error is 288 * thrown during the synctask. 289 */ 290 zch = zcp_register_cleanup(state, 291 (zcp_cleanup_t *)&fnvlist_free, err_details); 292 293 zcp_synctask_info_t *info = lua_touserdata(state, lua_upvalueindex(1)); 294 boolean_t sync = lua_toboolean(state, lua_upvalueindex(2)); 295 296 zcp_run_info_t *ri = zcp_run_info(state); 297 dsl_pool_t *dp = ri->zri_pool; 298 299 /* MOS space is triple-dittoed, so we multiply by 3. */ 300 uint64_t funcspace = (info->blocks_modified << DST_AVG_BLKSHIFT) * 3; 301 302 zcp_parse_args(state, info->name, info->pargs, info->kwargs); 303 304 err = 0; 305 if (info->space_check != ZFS_SPACE_CHECK_NONE) { 306 uint64_t quota = dsl_pool_unreserved_space(dp, 307 info->space_check); 308 uint64_t used = dsl_dir_phys(dp->dp_root_dir)->dd_used_bytes + 309 ri->zri_space_used; 310 311 if (used + funcspace > quota) { 312 err = SET_ERROR(ENOSPC); 313 } 314 } 315 316 if (err == 0) { 317 err = info->func(state, sync, err_details); 318 } 319 320 if (err == 0) { 321 ri->zri_space_used += funcspace; 322 } 323 324 lua_pushnumber(state, (lua_Number)err); 325 if (fnvlist_num_pairs(err_details) > 0) { 326 (void) zcp_nvlist_to_lua(state, err_details, NULL, 0); 327 num_ret++; 328 } 329 330 zcp_deregister_cleanup(state, zch); 331 fnvlist_free(err_details); 332 333 return (num_ret); 334 } 335 336 int 337 zcp_load_synctask_lib(lua_State *state, boolean_t sync) 338 { 339 int i; 340 zcp_synctask_info_t *zcp_synctask_funcs[] = { 341 &zcp_synctask_destroy_info, 342 &zcp_synctask_promote_info, 343 &zcp_synctask_rollback_info, 344 &zcp_synctask_snapshot_info, 345 NULL 346 }; 347 348 lua_newtable(state); 349 350 for (i = 0; zcp_synctask_funcs[i] != NULL; i++) { 351 zcp_synctask_info_t *info = zcp_synctask_funcs[i]; 352 lua_pushlightuserdata(state, info); 353 lua_pushboolean(state, sync); 354 lua_pushcclosure(state, &zcp_synctask_wrapper, 2); 355 lua_setfield(state, -2, info->name); 356 info++; 357 } 358 359 return (1); 360 } 361