libzfs_iter.c revision 277587
1/* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 22/* 23 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved. 24 * Copyright (c) 2013 by Delphix. All rights reserved. 25 * Copyright (c) 2012 Pawel Jakub Dawidek <pawel@dawidek.net>. 26 * All rights reserved. 27 * Copyright 2014 Nexenta Systems, Inc. All rights reserved. 28 */ 29 30#include <stdio.h> 31#include <stdlib.h> 32#include <strings.h> 33#include <unistd.h> 34#include <stddef.h> 35#include <libintl.h> 36#include <libzfs.h> 37 38#include "libzfs_impl.h" 39 40int 41zfs_iter_clones(zfs_handle_t *zhp, zfs_iter_f func, void *data) 42{ 43 nvlist_t *nvl = zfs_get_clones_nvl(zhp); 44 nvpair_t *pair; 45 46 if (nvl == NULL) 47 return (0); 48 49 for (pair = nvlist_next_nvpair(nvl, NULL); pair != NULL; 50 pair = nvlist_next_nvpair(nvl, pair)) { 51 zfs_handle_t *clone = zfs_open(zhp->zfs_hdl, nvpair_name(pair), 52 ZFS_TYPE_FILESYSTEM | ZFS_TYPE_VOLUME); 53 if (clone != NULL) { 54 int err = func(clone, data); 55 if (err != 0) 56 return (err); 57 } 58 } 59 return (0); 60} 61 62static int 63zfs_do_list_ioctl(zfs_handle_t *zhp, unsigned long arg, zfs_cmd_t *zc) 64{ 65 int rc; 66 uint64_t orig_cookie; 67 68 orig_cookie = zc->zc_cookie; 69top: 70 (void) strlcpy(zc->zc_name, zhp->zfs_name, sizeof (zc->zc_name)); 71 rc = ioctl(zhp->zfs_hdl->libzfs_fd, arg, zc); 72 73 if (rc == -1) { 74 switch (errno) { 75 case ENOMEM: 76 /* expand nvlist memory and try again */ 77 if (zcmd_expand_dst_nvlist(zhp->zfs_hdl, zc) != 0) { 78 zcmd_free_nvlists(zc); 79 return (-1); 80 } 81 zc->zc_cookie = orig_cookie; 82 goto top; 83 /* 84 * An errno value of ESRCH indicates normal completion. 85 * If ENOENT is returned, then the underlying dataset 86 * has been removed since we obtained the handle. 87 */ 88 case ESRCH: 89 case ENOENT: 90 rc = 1; 91 break; 92 default: 93 rc = zfs_standard_error(zhp->zfs_hdl, errno, 94 dgettext(TEXT_DOMAIN, 95 "cannot iterate filesystems")); 96 break; 97 } 98 } 99 return (rc); 100} 101 102/* 103 * Iterate over all child filesystems 104 */ 105int 106zfs_iter_filesystems(zfs_handle_t *zhp, zfs_iter_f func, void *data) 107{ 108 zfs_cmd_t zc = { 0 }; 109 zfs_handle_t *nzhp; 110 int ret; 111 112 if (zhp->zfs_type != ZFS_TYPE_FILESYSTEM) 113 return (0); 114 115 if (zcmd_alloc_dst_nvlist(zhp->zfs_hdl, &zc, 0) != 0) 116 return (-1); 117 118 while ((ret = zfs_do_list_ioctl(zhp, ZFS_IOC_DATASET_LIST_NEXT, 119 &zc)) == 0) { 120 /* 121 * Silently ignore errors, as the only plausible explanation is 122 * that the pool has since been removed. 123 */ 124 if ((nzhp = make_dataset_handle_zc(zhp->zfs_hdl, 125 &zc)) == NULL) { 126 continue; 127 } 128 129 if ((ret = func(nzhp, data)) != 0) { 130 zcmd_free_nvlists(&zc); 131 return (ret); 132 } 133 } 134 zcmd_free_nvlists(&zc); 135 return ((ret < 0) ? ret : 0); 136} 137 138/* 139 * Iterate over all snapshots 140 */ 141int 142zfs_iter_snapshots(zfs_handle_t *zhp, boolean_t simple, zfs_iter_f func, 143 void *data) 144{ 145 zfs_cmd_t zc = { 0 }; 146 zfs_handle_t *nzhp; 147 int ret; 148 149 if (zhp->zfs_type == ZFS_TYPE_SNAPSHOT || 150 zhp->zfs_type == ZFS_TYPE_BOOKMARK) 151 return (0); 152 153 zc.zc_simple = simple; 154 155 if (zcmd_alloc_dst_nvlist(zhp->zfs_hdl, &zc, 0) != 0) 156 return (-1); 157 while ((ret = zfs_do_list_ioctl(zhp, ZFS_IOC_SNAPSHOT_LIST_NEXT, 158 &zc)) == 0) { 159 160 if (simple) 161 nzhp = make_dataset_simple_handle_zc(zhp, &zc); 162 else 163 nzhp = make_dataset_handle_zc(zhp->zfs_hdl, &zc); 164 if (nzhp == NULL) 165 continue; 166 167 if ((ret = func(nzhp, data)) != 0) { 168 zcmd_free_nvlists(&zc); 169 return (ret); 170 } 171 } 172 zcmd_free_nvlists(&zc); 173 return ((ret < 0) ? ret : 0); 174} 175 176/* 177 * Iterate over all bookmarks 178 */ 179int 180zfs_iter_bookmarks(zfs_handle_t *zhp, zfs_iter_f func, void *data) 181{ 182 zfs_handle_t *nzhp; 183 nvlist_t *props = NULL; 184 nvlist_t *bmarks = NULL; 185 int err; 186 187 if ((zfs_get_type(zhp) & (ZFS_TYPE_SNAPSHOT | ZFS_TYPE_BOOKMARK)) != 0) 188 return (0); 189 190 /* Setup the requested properties nvlist. */ 191 props = fnvlist_alloc(); 192 fnvlist_add_boolean(props, zfs_prop_to_name(ZFS_PROP_GUID)); 193 fnvlist_add_boolean(props, zfs_prop_to_name(ZFS_PROP_CREATETXG)); 194 fnvlist_add_boolean(props, zfs_prop_to_name(ZFS_PROP_CREATION)); 195 196 if ((err = lzc_get_bookmarks(zhp->zfs_name, props, &bmarks)) != 0) 197 goto out; 198 199 for (nvpair_t *pair = nvlist_next_nvpair(bmarks, NULL); 200 pair != NULL; pair = nvlist_next_nvpair(bmarks, pair)) { 201 char name[ZFS_MAXNAMELEN]; 202 char *bmark_name; 203 nvlist_t *bmark_props; 204 205 bmark_name = nvpair_name(pair); 206 bmark_props = fnvpair_value_nvlist(pair); 207 208 (void) snprintf(name, sizeof (name), "%s#%s", zhp->zfs_name, 209 bmark_name); 210 211 nzhp = make_bookmark_handle(zhp, name, bmark_props); 212 if (nzhp == NULL) 213 continue; 214 215 if ((err = func(nzhp, data)) != 0) 216 goto out; 217 } 218 219out: 220 fnvlist_free(props); 221 fnvlist_free(bmarks); 222 223 return (err); 224} 225 226/* 227 * Routines for dealing with the sorted snapshot functionality 228 */ 229typedef struct zfs_node { 230 zfs_handle_t *zn_handle; 231 avl_node_t zn_avlnode; 232} zfs_node_t; 233 234static int 235zfs_sort_snaps(zfs_handle_t *zhp, void *data) 236{ 237 avl_tree_t *avl = data; 238 zfs_node_t *node; 239 zfs_node_t search; 240 241 search.zn_handle = zhp; 242 node = avl_find(avl, &search, NULL); 243 if (node) { 244 /* 245 * If this snapshot was renamed while we were creating the 246 * AVL tree, it's possible that we already inserted it under 247 * its old name. Remove the old handle before adding the new 248 * one. 249 */ 250 zfs_close(node->zn_handle); 251 avl_remove(avl, node); 252 free(node); 253 } 254 255 node = zfs_alloc(zhp->zfs_hdl, sizeof (zfs_node_t)); 256 node->zn_handle = zhp; 257 avl_add(avl, node); 258 259 return (0); 260} 261 262static int 263zfs_snapshot_compare(const void *larg, const void *rarg) 264{ 265 zfs_handle_t *l = ((zfs_node_t *)larg)->zn_handle; 266 zfs_handle_t *r = ((zfs_node_t *)rarg)->zn_handle; 267 uint64_t lcreate, rcreate; 268 269 /* 270 * Sort them according to creation time. We use the hidden 271 * CREATETXG property to get an absolute ordering of snapshots. 272 */ 273 lcreate = zfs_prop_get_int(l, ZFS_PROP_CREATETXG); 274 rcreate = zfs_prop_get_int(r, ZFS_PROP_CREATETXG); 275 276 if (lcreate < rcreate) 277 return (-1); 278 else if (lcreate > rcreate) 279 return (+1); 280 else 281 return (0); 282} 283 284int 285zfs_iter_snapshots_sorted(zfs_handle_t *zhp, zfs_iter_f callback, void *data) 286{ 287 int ret = 0; 288 zfs_node_t *node; 289 avl_tree_t avl; 290 void *cookie = NULL; 291 292 avl_create(&avl, zfs_snapshot_compare, 293 sizeof (zfs_node_t), offsetof(zfs_node_t, zn_avlnode)); 294 295 ret = zfs_iter_snapshots(zhp, B_FALSE, zfs_sort_snaps, &avl); 296 297 for (node = avl_first(&avl); node != NULL; node = AVL_NEXT(&avl, node)) 298 ret |= callback(node->zn_handle, data); 299 300 while ((node = avl_destroy_nodes(&avl, &cookie)) != NULL) 301 free(node); 302 303 avl_destroy(&avl); 304 305 return (ret); 306} 307 308typedef struct { 309 char *ssa_first; 310 char *ssa_last; 311 boolean_t ssa_seenfirst; 312 boolean_t ssa_seenlast; 313 zfs_iter_f ssa_func; 314 void *ssa_arg; 315} snapspec_arg_t; 316 317static int 318snapspec_cb(zfs_handle_t *zhp, void *arg) { 319 snapspec_arg_t *ssa = arg; 320 char *shortsnapname; 321 int err = 0; 322 323 if (ssa->ssa_seenlast) 324 return (0); 325 shortsnapname = zfs_strdup(zhp->zfs_hdl, 326 strchr(zfs_get_name(zhp), '@') + 1); 327 328 if (!ssa->ssa_seenfirst && strcmp(shortsnapname, ssa->ssa_first) == 0) 329 ssa->ssa_seenfirst = B_TRUE; 330 331 if (ssa->ssa_seenfirst) { 332 err = ssa->ssa_func(zhp, ssa->ssa_arg); 333 } else { 334 zfs_close(zhp); 335 } 336 337 if (strcmp(shortsnapname, ssa->ssa_last) == 0) 338 ssa->ssa_seenlast = B_TRUE; 339 free(shortsnapname); 340 341 return (err); 342} 343 344/* 345 * spec is a string like "A,B%C,D" 346 * 347 * <snaps>, where <snaps> can be: 348 * <snap> (single snapshot) 349 * <snap>%<snap> (range of snapshots, inclusive) 350 * %<snap> (range of snapshots, starting with earliest) 351 * <snap>% (range of snapshots, ending with last) 352 * % (all snapshots) 353 * <snaps>[,...] (comma separated list of the above) 354 * 355 * If a snapshot can not be opened, continue trying to open the others, but 356 * return ENOENT at the end. 357 */ 358int 359zfs_iter_snapspec(zfs_handle_t *fs_zhp, const char *spec_orig, 360 zfs_iter_f func, void *arg) 361{ 362 char *buf, *comma_separated, *cp; 363 int err = 0; 364 int ret = 0; 365 366 buf = zfs_strdup(fs_zhp->zfs_hdl, spec_orig); 367 cp = buf; 368 369 while ((comma_separated = strsep(&cp, ",")) != NULL) { 370 char *pct = strchr(comma_separated, '%'); 371 if (pct != NULL) { 372 snapspec_arg_t ssa = { 0 }; 373 ssa.ssa_func = func; 374 ssa.ssa_arg = arg; 375 376 if (pct == comma_separated) 377 ssa.ssa_seenfirst = B_TRUE; 378 else 379 ssa.ssa_first = comma_separated; 380 *pct = '\0'; 381 ssa.ssa_last = pct + 1; 382 383 /* 384 * If there is a lastname specified, make sure it 385 * exists. 386 */ 387 if (ssa.ssa_last[0] != '\0') { 388 char snapname[ZFS_MAXNAMELEN]; 389 (void) snprintf(snapname, sizeof (snapname), 390 "%s@%s", zfs_get_name(fs_zhp), 391 ssa.ssa_last); 392 if (!zfs_dataset_exists(fs_zhp->zfs_hdl, 393 snapname, ZFS_TYPE_SNAPSHOT)) { 394 ret = ENOENT; 395 continue; 396 } 397 } 398 399 err = zfs_iter_snapshots_sorted(fs_zhp, 400 snapspec_cb, &ssa); 401 if (ret == 0) 402 ret = err; 403 if (ret == 0 && (!ssa.ssa_seenfirst || 404 (ssa.ssa_last[0] != '\0' && !ssa.ssa_seenlast))) { 405 ret = ENOENT; 406 } 407 } else { 408 char snapname[ZFS_MAXNAMELEN]; 409 zfs_handle_t *snap_zhp; 410 (void) snprintf(snapname, sizeof (snapname), "%s@%s", 411 zfs_get_name(fs_zhp), comma_separated); 412 snap_zhp = make_dataset_handle(fs_zhp->zfs_hdl, 413 snapname); 414 if (snap_zhp == NULL) { 415 ret = ENOENT; 416 continue; 417 } 418 err = func(snap_zhp, arg); 419 if (ret == 0) 420 ret = err; 421 } 422 } 423 424 free(buf); 425 return (ret); 426} 427 428/* 429 * Iterate over all children, snapshots and filesystems 430 */ 431int 432zfs_iter_children(zfs_handle_t *zhp, zfs_iter_f func, void *data) 433{ 434 int ret; 435 436 if ((ret = zfs_iter_filesystems(zhp, func, data)) != 0) 437 return (ret); 438 439 return (zfs_iter_snapshots(zhp, B_FALSE, func, data)); 440} 441 442 443typedef struct iter_stack_frame { 444 struct iter_stack_frame *next; 445 zfs_handle_t *zhp; 446} iter_stack_frame_t; 447 448typedef struct iter_dependents_arg { 449 boolean_t first; 450 boolean_t allowrecursion; 451 iter_stack_frame_t *stack; 452 zfs_iter_f func; 453 void *data; 454} iter_dependents_arg_t; 455 456static int 457iter_dependents_cb(zfs_handle_t *zhp, void *arg) 458{ 459 iter_dependents_arg_t *ida = arg; 460 int err = 0; 461 boolean_t first = ida->first; 462 ida->first = B_FALSE; 463 464 if (zhp->zfs_type == ZFS_TYPE_SNAPSHOT) { 465 err = zfs_iter_clones(zhp, iter_dependents_cb, ida); 466 } else if (zhp->zfs_type != ZFS_TYPE_BOOKMARK) { 467 iter_stack_frame_t isf; 468 iter_stack_frame_t *f; 469 470 /* 471 * check if there is a cycle by seeing if this fs is already 472 * on the stack. 473 */ 474 for (f = ida->stack; f != NULL; f = f->next) { 475 if (f->zhp->zfs_dmustats.dds_guid == 476 zhp->zfs_dmustats.dds_guid) { 477 if (ida->allowrecursion) { 478 zfs_close(zhp); 479 return (0); 480 } else { 481 zfs_error_aux(zhp->zfs_hdl, 482 dgettext(TEXT_DOMAIN, 483 "recursive dependency at '%s'"), 484 zfs_get_name(zhp)); 485 err = zfs_error(zhp->zfs_hdl, 486 EZFS_RECURSIVE, 487 dgettext(TEXT_DOMAIN, 488 "cannot determine dependent " 489 "datasets")); 490 zfs_close(zhp); 491 return (err); 492 } 493 } 494 } 495 496 isf.zhp = zhp; 497 isf.next = ida->stack; 498 ida->stack = &isf; 499 err = zfs_iter_filesystems(zhp, iter_dependents_cb, ida); 500 if (err == 0) { 501 err = zfs_iter_snapshots(zhp, B_FALSE, 502 iter_dependents_cb, ida); 503 } 504 ida->stack = isf.next; 505 } 506 507 if (!first && err == 0) 508 err = ida->func(zhp, ida->data); 509 else 510 zfs_close(zhp); 511 512 return (err); 513} 514 515int 516zfs_iter_dependents(zfs_handle_t *zhp, boolean_t allowrecursion, 517 zfs_iter_f func, void *data) 518{ 519 iter_dependents_arg_t ida; 520 ida.allowrecursion = allowrecursion; 521 ida.stack = NULL; 522 ida.func = func; 523 ida.data = data; 524 ida.first = B_TRUE; 525 return (iter_dependents_cb(zfs_handle_dup(zhp), &ida)); 526} 527