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 2010 Nexenta Systems, Inc. All rights reserved.
25 * Copyright (c) 2011 by Delphix. All rights reserved.
26 */
27
28 #include <stdio.h>
29 #include <stdlib.h>
30 #include <strings.h>
31 #include <unistd.h>
32 #include <stddef.h>
33 #include <libintl.h>
34 #include <libzfs.h>
35
36 #include "libzfs_impl.h"
37
38 int
39 zfs_iter_clones(zfs_handle_t *zhp, zfs_iter_f func, void *data)
40 {
41 nvlist_t *nvl = zfs_get_clones_nvl(zhp);
42 nvpair_t *pair;
43
44 if (nvl == NULL)
45 return (0);
46
47 for (pair = nvlist_next_nvpair(nvl, NULL); pair != NULL;
48 pair = nvlist_next_nvpair(nvl, pair)) {
49 zfs_handle_t *clone = zfs_open(zhp->zfs_hdl, nvpair_name(pair),
50 ZFS_TYPE_FILESYSTEM | ZFS_TYPE_VOLUME);
51 if (clone != NULL) {
52 int err = func(clone, data);
53 if (err != 0)
54 return (err);
55 }
56 }
57 return (0);
58 }
59
60 static int
61 zfs_do_list_ioctl(zfs_handle_t *zhp, int arg, zfs_cmd_t *zc)
62 {
63 int rc;
64 uint64_t orig_cookie;
65
66 orig_cookie = zc->zc_cookie;
67 top:
68 (void) strlcpy(zc->zc_name, zhp->zfs_name, sizeof (zc->zc_name));
69 rc = ioctl(zhp->zfs_hdl->libzfs_fd, arg, zc);
70
71 if (rc == -1) {
72 switch (errno) {
73 case ENOMEM:
74 /* expand nvlist memory and try again */
75 if (zcmd_expand_dst_nvlist(zhp->zfs_hdl, zc) != 0) {
76 zcmd_free_nvlists(zc);
77 return (-1);
78 }
79 zc->zc_cookie = orig_cookie;
80 goto top;
81 /*
82 * An errno value of ESRCH indicates normal completion.
83 * If ENOENT is returned, then the underlying dataset
84 * has been removed since we obtained the handle.
85 */
86 case ESRCH:
87 case ENOENT:
88 rc = 1;
89 break;
90 default:
91 rc = zfs_standard_error(zhp->zfs_hdl, errno,
92 dgettext(TEXT_DOMAIN,
93 "cannot iterate filesystems"));
94 break;
95 }
96 }
97 return (rc);
98 }
99
100 /*
101 * Iterate over all child filesystems
102 */
103 int
104 zfs_iter_filesystems(zfs_handle_t *zhp, zfs_iter_f func, void *data)
105 {
106 zfs_cmd_t zc = { 0 };
107 zfs_handle_t *nzhp;
108 int ret;
109
110 if (zhp->zfs_type != ZFS_TYPE_FILESYSTEM)
111 return (0);
112
113 if (zcmd_alloc_dst_nvlist(zhp->zfs_hdl, &zc, 0) != 0)
114 return (-1);
115
116 while ((ret = zfs_do_list_ioctl(zhp, ZFS_IOC_DATASET_LIST_NEXT,
117 &zc)) == 0) {
118 /*
119 * Silently ignore errors, as the only plausible explanation is
120 * that the pool has since been removed.
121 */
122 if ((nzhp = make_dataset_handle_zc(zhp->zfs_hdl,
123 &zc)) == NULL) {
124 continue;
125 }
126
127 if ((ret = func(nzhp, data)) != 0) {
128 zcmd_free_nvlists(&zc);
129 return (ret);
130 }
131 }
132 zcmd_free_nvlists(&zc);
133 return ((ret < 0) ? ret : 0);
134 }
135
136 /*
137 * Iterate over all snapshots
138 */
139 int
140 zfs_iter_snapshots(zfs_handle_t *zhp, zfs_iter_f func, void *data)
141 {
142 zfs_cmd_t zc = { 0 };
143 zfs_handle_t *nzhp;
144 int ret;
145
146 if (zhp->zfs_type == ZFS_TYPE_SNAPSHOT)
147 return (0);
148
149 if (zcmd_alloc_dst_nvlist(zhp->zfs_hdl, &zc, 0) != 0)
150 return (-1);
151 while ((ret = zfs_do_list_ioctl(zhp, ZFS_IOC_SNAPSHOT_LIST_NEXT,
152 &zc)) == 0) {
153
154 if ((nzhp = make_dataset_handle_zc(zhp->zfs_hdl,
155 &zc)) == NULL) {
156 continue;
157 }
158
159 if ((ret = func(nzhp, data)) != 0) {
160 zcmd_free_nvlists(&zc);
161 return (ret);
162 }
163 }
164 zcmd_free_nvlists(&zc);
165 return ((ret < 0) ? ret : 0);
166 }
167
168 /*
169 * Routines for dealing with the sorted snapshot functionality
170 */
171 typedef struct zfs_node {
172 zfs_handle_t *zn_handle;
173 avl_node_t zn_avlnode;
174 } zfs_node_t;
175
176 static int
177 zfs_sort_snaps(zfs_handle_t *zhp, void *data)
178 {
179 avl_tree_t *avl = data;
180 zfs_node_t *node;
181 zfs_node_t search;
182
183 search.zn_handle = zhp;
184 node = avl_find(avl, &search, NULL);
185 if (node) {
186 /*
187 * If this snapshot was renamed while we were creating the
188 * AVL tree, it's possible that we already inserted it under
189 * its old name. Remove the old handle before adding the new
190 * one.
191 */
192 zfs_close(node->zn_handle);
193 avl_remove(avl, node);
194 free(node);
195 }
196
197 node = zfs_alloc(zhp->zfs_hdl, sizeof (zfs_node_t));
198 node->zn_handle = zhp;
199 avl_add(avl, node);
200
201 return (0);
202 }
203
204 static int
205 zfs_snapshot_compare(const void *larg, const void *rarg)
206 {
207 zfs_handle_t *l = ((zfs_node_t *)larg)->zn_handle;
208 zfs_handle_t *r = ((zfs_node_t *)rarg)->zn_handle;
209 uint64_t lcreate, rcreate;
210
211 /*
212 * Sort them according to creation time. We use the hidden
213 * CREATETXG property to get an absolute ordering of snapshots.
214 */
215 lcreate = zfs_prop_get_int(l, ZFS_PROP_CREATETXG);
216 rcreate = zfs_prop_get_int(r, ZFS_PROP_CREATETXG);
217
218 if (lcreate < rcreate)
219 return (-1);
220 else if (lcreate > rcreate)
221 return (+1);
222 else
223 return (0);
224 }
225
226 int
227 zfs_iter_snapshots_sorted(zfs_handle_t *zhp, zfs_iter_f callback, void *data)
228 {
229 int ret = 0;
230 zfs_node_t *node;
231 avl_tree_t avl;
232 void *cookie = NULL;
233
234 avl_create(&avl, zfs_snapshot_compare,
235 sizeof (zfs_node_t), offsetof(zfs_node_t, zn_avlnode));
236
237 ret = zfs_iter_snapshots(zhp, zfs_sort_snaps, &avl);
238
239 for (node = avl_first(&avl); node != NULL; node = AVL_NEXT(&avl, node))
240 ret |= callback(node->zn_handle, data);
241
242 while ((node = avl_destroy_nodes(&avl, &cookie)) != NULL)
243 free(node);
244
245 avl_destroy(&avl);
246
247 return (ret);
248 }
249
250 typedef struct {
251 char *ssa_first;
252 char *ssa_last;
253 boolean_t ssa_seenfirst;
254 boolean_t ssa_seenlast;
255 zfs_iter_f ssa_func;
256 void *ssa_arg;
257 } snapspec_arg_t;
258
259 static int
260 snapspec_cb(zfs_handle_t *zhp, void *arg) {
261 snapspec_arg_t *ssa = arg;
262 char *shortsnapname;
263 int err = 0;
264
265 if (ssa->ssa_seenlast)
266 return (0);
267 shortsnapname = zfs_strdup(zhp->zfs_hdl,
268 strchr(zfs_get_name(zhp), '@') + 1);
269
270 if (!ssa->ssa_seenfirst && strcmp(shortsnapname, ssa->ssa_first) == 0)
271 ssa->ssa_seenfirst = B_TRUE;
272
273 if (ssa->ssa_seenfirst) {
274 err = ssa->ssa_func(zhp, ssa->ssa_arg);
275 } else {
276 zfs_close(zhp);
277 }
278
279 if (strcmp(shortsnapname, ssa->ssa_last) == 0)
280 ssa->ssa_seenlast = B_TRUE;
281 free(shortsnapname);
282
283 return (err);
284 }
285
286 /*
287 * spec is a string like "A,B%C,D"
288 *
289 * <snaps>, where <snaps> can be:
290 * <snap> (single snapshot)
291 * <snap>%<snap> (range of snapshots, inclusive)
292 * %<snap> (range of snapshots, starting with earliest)
293 * <snap>% (range of snapshots, ending with last)
294 * % (all snapshots)
295 * <snaps>[,...] (comma separated list of the above)
296 *
297 * If a snapshot can not be opened, continue trying to open the others, but
298 * return ENOENT at the end.
299 */
300 int
301 zfs_iter_snapspec(zfs_handle_t *fs_zhp, const char *spec_orig,
302 zfs_iter_f func, void *arg)
303 {
304 char buf[ZFS_MAXNAMELEN];
305 char *comma_separated, *cp;
306 int err = 0;
307 int ret = 0;
308
309 (void) strlcpy(buf, spec_orig, sizeof (buf));
310 cp = buf;
311
312 while ((comma_separated = strsep(&cp, ",")) != NULL) {
313 char *pct = strchr(comma_separated, '%');
314 if (pct != NULL) {
315 snapspec_arg_t ssa = { 0 };
316 ssa.ssa_func = func;
317 ssa.ssa_arg = arg;
318
319 if (pct == comma_separated)
320 ssa.ssa_seenfirst = B_TRUE;
321 else
322 ssa.ssa_first = comma_separated;
323 *pct = '\0';
324 ssa.ssa_last = pct + 1;
325
326 /*
327 * If there is a lastname specified, make sure it
328 * exists.
329 */
330 if (ssa.ssa_last[0] != '\0') {
331 char snapname[ZFS_MAXNAMELEN];
332 (void) snprintf(snapname, sizeof (snapname),
333 "%s@%s", zfs_get_name(fs_zhp),
334 ssa.ssa_last);
335 if (!zfs_dataset_exists(fs_zhp->zfs_hdl,
336 snapname, ZFS_TYPE_SNAPSHOT)) {
337 ret = ENOENT;
338 continue;
339 }
340 }
341
342 err = zfs_iter_snapshots_sorted(fs_zhp,
343 snapspec_cb, &ssa);
344 if (ret == 0)
345 ret = err;
346 if (ret == 0 && (!ssa.ssa_seenfirst ||
347 (ssa.ssa_last[0] != '\0' && !ssa.ssa_seenlast))) {
348 ret = ENOENT;
349 }
350 } else {
351 char snapname[ZFS_MAXNAMELEN];
352 zfs_handle_t *snap_zhp;
353 (void) snprintf(snapname, sizeof (snapname), "%s@%s",
354 zfs_get_name(fs_zhp), comma_separated);
355 snap_zhp = make_dataset_handle(fs_zhp->zfs_hdl,
356 snapname);
357 if (snap_zhp == NULL) {
358 ret = ENOENT;
359 continue;
360 }
361 err = func(snap_zhp, arg);
362 if (ret == 0)
363 ret = err;
364 }
365 }
366
367 return (ret);
368 }
369
370 /*
371 * Iterate over all children, snapshots and filesystems
372 */
373 int
374 zfs_iter_children(zfs_handle_t *zhp, zfs_iter_f func, void *data)
375 {
376 int ret;
377
378 if ((ret = zfs_iter_filesystems(zhp, func, data)) != 0)
379 return (ret);
380
381 return (zfs_iter_snapshots(zhp, func, data));
382 }
383
384
385 typedef struct iter_stack_frame {
386 struct iter_stack_frame *next;
387 zfs_handle_t *zhp;
388 } iter_stack_frame_t;
389
390 typedef struct iter_dependents_arg {
391 boolean_t first;
392 boolean_t allowrecursion;
393 iter_stack_frame_t *stack;
394 zfs_iter_f func;
395 void *data;
396 } iter_dependents_arg_t;
397
398 static int
399 iter_dependents_cb(zfs_handle_t *zhp, void *arg)
400 {
401 iter_dependents_arg_t *ida = arg;
402 int err;
403 boolean_t first = ida->first;
404 ida->first = B_FALSE;
405
406 if (zhp->zfs_type == ZFS_TYPE_SNAPSHOT) {
407 err = zfs_iter_clones(zhp, iter_dependents_cb, ida);
408 } else {
409 iter_stack_frame_t isf;
410 iter_stack_frame_t *f;
411
412 /*
413 * check if there is a cycle by seeing if this fs is already
414 * on the stack.
415 */
416 for (f = ida->stack; f != NULL; f = f->next) {
417 if (f->zhp->zfs_dmustats.dds_guid ==
418 zhp->zfs_dmustats.dds_guid) {
419 if (ida->allowrecursion) {
420 zfs_close(zhp);
421 return (0);
422 } else {
423 zfs_error_aux(zhp->zfs_hdl,
424 dgettext(TEXT_DOMAIN,
425 "recursive dependency at '%s'"),
426 zfs_get_name(zhp));
427 err = zfs_error(zhp->zfs_hdl,
428 EZFS_RECURSIVE,
429 dgettext(TEXT_DOMAIN,
430 "cannot determine dependent "
431 "datasets"));
432 zfs_close(zhp);
433 return (err);
434 }
435 }
436 }
437
438 isf.zhp = zhp;
439 isf.next = ida->stack;
440 ida->stack = &isf;
441 err = zfs_iter_filesystems(zhp, iter_dependents_cb, ida);
442 if (err == 0)
443 err = zfs_iter_snapshots(zhp, iter_dependents_cb, ida);
444 ida->stack = isf.next;
445 }
446 if (!first && err == 0)
447 err = ida->func(zhp, ida->data);
448 return (err);
449 }
450
451 int
452 zfs_iter_dependents(zfs_handle_t *zhp, boolean_t allowrecursion,
453 zfs_iter_f func, void *data)
454 {
455 iter_dependents_arg_t ida;
456 ida.allowrecursion = allowrecursion;
457 ida.stack = NULL;
458 ida.func = func;
459 ida.data = data;
460 ida.first = B_TRUE;
461 return (iter_dependents_cb(zfs_handle_dup(zhp), &ida));
462 }