Training courses

Kernel and Embedded Linux

Bootlin training courses

Embedded Linux, kernel,
Yocto Project, Buildroot, real-time,
graphics, boot time, debugging...

Bootlin logo

Elixir Cross Referencer

  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */

/*
 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
 * Copyright (c) 2013, 2015 by Delphix. All rights reserved.
 * Copyright (c) 2012 Pawel Jakub Dawidek. All rights reserved.
 * Copyright 2014 Nexenta Systems, Inc.  All rights reserved.
 */

#include <stdio.h>
#include <stdlib.h>
#include <strings.h>
#include <unistd.h>
#include <stddef.h>
#include <libintl.h>
#include <libzfs.h>

#include "libzfs_impl.h"

int
zfs_iter_clones(zfs_handle_t *zhp, zfs_iter_f func, void *data)
{
	nvlist_t *nvl = zfs_get_clones_nvl(zhp);
	nvpair_t *pair;

	if (nvl == NULL)
		return (0);

	for (pair = nvlist_next_nvpair(nvl, NULL); pair != NULL;
	    pair = nvlist_next_nvpair(nvl, pair)) {
		zfs_handle_t *clone = zfs_open(zhp->zfs_hdl, nvpair_name(pair),
		    ZFS_TYPE_FILESYSTEM | ZFS_TYPE_VOLUME);
		if (clone != NULL) {
			int err = func(clone, data);
			if (err != 0)
				return (err);
		}
	}
	return (0);
}

static int
zfs_do_list_ioctl(zfs_handle_t *zhp, unsigned long arg, zfs_cmd_t *zc)
{
	int rc;
	uint64_t	orig_cookie;

	orig_cookie = zc->zc_cookie;
top:
	(void) strlcpy(zc->zc_name, zhp->zfs_name, sizeof (zc->zc_name));
	rc = ioctl(zhp->zfs_hdl->libzfs_fd, arg, zc);

	if (rc == -1) {
		switch (errno) {
		case ENOMEM:
			/* expand nvlist memory and try again */
			if (zcmd_expand_dst_nvlist(zhp->zfs_hdl, zc) != 0) {
				zcmd_free_nvlists(zc);
				return (-1);
			}
			zc->zc_cookie = orig_cookie;
			goto top;
		/*
		 * An errno value of ESRCH indicates normal completion.
		 * If ENOENT is returned, then the underlying dataset
		 * has been removed since we obtained the handle.
		 */
		case ESRCH:
		case ENOENT:
			rc = 1;
			break;
		default:
			rc = zfs_standard_error(zhp->zfs_hdl, errno,
			    dgettext(TEXT_DOMAIN,
			    "cannot iterate filesystems"));
			break;
		}
	}
	return (rc);
}

/*
 * Iterate over all child filesystems
 */
int
zfs_iter_filesystems(zfs_handle_t *zhp, zfs_iter_f func, void *data)
{
	zfs_cmd_t zc = { 0 };
	zfs_handle_t *nzhp;
	int ret;

	if (zhp->zfs_type != ZFS_TYPE_FILESYSTEM)
		return (0);

	if (zcmd_alloc_dst_nvlist(zhp->zfs_hdl, &zc, 0) != 0)
		return (-1);

	while ((ret = zfs_do_list_ioctl(zhp, ZFS_IOC_DATASET_LIST_NEXT,
	    &zc)) == 0) {
		/*
		 * Silently ignore errors, as the only plausible explanation is
		 * that the pool has since been removed.
		 */
		if ((nzhp = make_dataset_handle_zc(zhp->zfs_hdl,
		    &zc)) == NULL) {
			continue;
		}

		if ((ret = func(nzhp, data)) != 0) {
			zcmd_free_nvlists(&zc);
			return (ret);
		}
	}
	zcmd_free_nvlists(&zc);
	return ((ret < 0) ? ret : 0);
}

/*
 * Iterate over all snapshots
 */
int
zfs_iter_snapshots(zfs_handle_t *zhp, boolean_t simple, zfs_iter_f func,
    void *data)
{
	zfs_cmd_t zc = { 0 };
	zfs_handle_t *nzhp;
	int ret;

	if (zhp->zfs_type == ZFS_TYPE_SNAPSHOT ||
	    zhp->zfs_type == ZFS_TYPE_BOOKMARK)
		return (0);

	zc.zc_simple = simple;

	if (zcmd_alloc_dst_nvlist(zhp->zfs_hdl, &zc, 0) != 0)
		return (-1);
	while ((ret = zfs_do_list_ioctl(zhp, ZFS_IOC_SNAPSHOT_LIST_NEXT,
	    &zc)) == 0) {

		if (simple)
			nzhp = make_dataset_simple_handle_zc(zhp, &zc);
		else
			nzhp = make_dataset_handle_zc(zhp->zfs_hdl, &zc);
		if (nzhp == NULL)
			continue;

		if ((ret = func(nzhp, data)) != 0) {
			zcmd_free_nvlists(&zc);
			return (ret);
		}
	}
	zcmd_free_nvlists(&zc);
	return ((ret < 0) ? ret : 0);
}

/*
 * Iterate over all bookmarks
 */
int
zfs_iter_bookmarks(zfs_handle_t *zhp, zfs_iter_f func, void *data)
{
	zfs_handle_t *nzhp;
	nvlist_t *props = NULL;
	nvlist_t *bmarks = NULL;
	int err;

	if ((zfs_get_type(zhp) & (ZFS_TYPE_SNAPSHOT | ZFS_TYPE_BOOKMARK)) != 0)
		return (0);

	/* Setup the requested properties nvlist. */
	props = fnvlist_alloc();
	fnvlist_add_boolean(props, zfs_prop_to_name(ZFS_PROP_GUID));
	fnvlist_add_boolean(props, zfs_prop_to_name(ZFS_PROP_CREATETXG));
	fnvlist_add_boolean(props, zfs_prop_to_name(ZFS_PROP_CREATION));

	if ((err = lzc_get_bookmarks(zhp->zfs_name, props, &bmarks)) != 0)
		goto out;

	for (nvpair_t *pair = nvlist_next_nvpair(bmarks, NULL);
	    pair != NULL; pair = nvlist_next_nvpair(bmarks, pair)) {
		char name[ZFS_MAX_DATASET_NAME_LEN];
		char *bmark_name;
		nvlist_t *bmark_props;

		bmark_name = nvpair_name(pair);
		bmark_props = fnvpair_value_nvlist(pair);

		(void) snprintf(name, sizeof (name), "%s#%s", zhp->zfs_name,
		    bmark_name);

		nzhp = make_bookmark_handle(zhp, name, bmark_props);
		if (nzhp == NULL)
			continue;

		if ((err = func(nzhp, data)) != 0)
			goto out;
	}

out:
	fnvlist_free(props);
	fnvlist_free(bmarks);

	return (err);
}

/*
 * Routines for dealing with the sorted snapshot functionality
 */
typedef struct zfs_node {
	zfs_handle_t	*zn_handle;
	avl_node_t	zn_avlnode;
} zfs_node_t;

static int
zfs_sort_snaps(zfs_handle_t *zhp, void *data)
{
	avl_tree_t *avl = data;
	zfs_node_t *node;
	zfs_node_t search;

	search.zn_handle = zhp;
	node = avl_find(avl, &search, NULL);
	if (node) {
		/*
		 * If this snapshot was renamed while we were creating the
		 * AVL tree, it's possible that we already inserted it under
		 * its old name. Remove the old handle before adding the new
		 * one.
		 */
		zfs_close(node->zn_handle);
		avl_remove(avl, node);
		free(node);
	}

	node = zfs_alloc(zhp->zfs_hdl, sizeof (zfs_node_t));
	node->zn_handle = zhp;
	avl_add(avl, node);

	return (0);
}

static int
zfs_snapshot_compare(const void *larg, const void *rarg)
{
	zfs_handle_t *l = ((zfs_node_t *)larg)->zn_handle;
	zfs_handle_t *r = ((zfs_node_t *)rarg)->zn_handle;
	uint64_t lcreate, rcreate;

	/*
	 * Sort them according to creation time.  We use the hidden
	 * CREATETXG property to get an absolute ordering of snapshots.
	 */
	lcreate = zfs_prop_get_int(l, ZFS_PROP_CREATETXG);
	rcreate = zfs_prop_get_int(r, ZFS_PROP_CREATETXG);

	if (lcreate < rcreate)
		return (-1);
	else if (lcreate > rcreate)
		return (+1);
	else
		return (0);
}

int
zfs_iter_snapshots_sorted(zfs_handle_t *zhp, zfs_iter_f callback, void *data)
{
	int ret = 0;
	zfs_node_t *node;
	avl_tree_t avl;
	void *cookie = NULL;

	avl_create(&avl, zfs_snapshot_compare,
	    sizeof (zfs_node_t), offsetof(zfs_node_t, zn_avlnode));

	ret = zfs_iter_snapshots(zhp, B_FALSE, zfs_sort_snaps, &avl);

	for (node = avl_first(&avl); node != NULL; node = AVL_NEXT(&avl, node))
		ret |= callback(node->zn_handle, data);

	while ((node = avl_destroy_nodes(&avl, &cookie)) != NULL)
		free(node);

	avl_destroy(&avl);

	return (ret);
}

typedef struct {
	char *ssa_first;
	char *ssa_last;
	boolean_t ssa_seenfirst;
	boolean_t ssa_seenlast;
	zfs_iter_f ssa_func;
	void *ssa_arg;
} snapspec_arg_t;

static int
snapspec_cb(zfs_handle_t *zhp, void *arg)
{
	snapspec_arg_t *ssa = arg;
	char *shortsnapname;
	int err = 0;

	if (ssa->ssa_seenlast)
		return (0);
	shortsnapname = zfs_strdup(zhp->zfs_hdl,
	    strchr(zfs_get_name(zhp), '@') + 1);

	if (!ssa->ssa_seenfirst && strcmp(shortsnapname, ssa->ssa_first) == 0)
		ssa->ssa_seenfirst = B_TRUE;

	if (ssa->ssa_seenfirst) {
		err = ssa->ssa_func(zhp, ssa->ssa_arg);
	} else {
		zfs_close(zhp);
	}

	if (strcmp(shortsnapname, ssa->ssa_last) == 0)
		ssa->ssa_seenlast = B_TRUE;
	free(shortsnapname);

	return (err);
}

/*
 * spec is a string like "A,B%C,D"
 *
 * <snaps>, where <snaps> can be:
 *      <snap>          (single snapshot)
 *      <snap>%<snap>   (range of snapshots, inclusive)
 *      %<snap>         (range of snapshots, starting with earliest)
 *      <snap>%         (range of snapshots, ending with last)
 *      %               (all snapshots)
 *      <snaps>[,...]   (comma separated list of the above)
 *
 * If a snapshot can not be opened, continue trying to open the others, but
 * return ENOENT at the end.
 */
int
zfs_iter_snapspec(zfs_handle_t *fs_zhp, const char *spec_orig,
    zfs_iter_f func, void *arg)
{
	char *buf, *comma_separated, *cp;
	int err = 0;
	int ret = 0;

	buf = zfs_strdup(fs_zhp->zfs_hdl, spec_orig);
	cp = buf;

	while ((comma_separated = strsep(&cp, ",")) != NULL) {
		char *pct = strchr(comma_separated, '%');
		if (pct != NULL) {
			snapspec_arg_t ssa = { 0 };
			ssa.ssa_func = func;
			ssa.ssa_arg = arg;

			if (pct == comma_separated)
				ssa.ssa_seenfirst = B_TRUE;
			else
				ssa.ssa_first = comma_separated;
			*pct = '\0';
			ssa.ssa_last = pct + 1;

			/*
			 * If there is a lastname specified, make sure it
			 * exists.
			 */
			if (ssa.ssa_last[0] != '\0') {
				char snapname[ZFS_MAX_DATASET_NAME_LEN];
				(void) snprintf(snapname, sizeof (snapname),
				    "%s@%s", zfs_get_name(fs_zhp),
				    ssa.ssa_last);
				if (!zfs_dataset_exists(fs_zhp->zfs_hdl,
				    snapname, ZFS_TYPE_SNAPSHOT)) {
					ret = ENOENT;
					continue;
				}
			}

			err = zfs_iter_snapshots_sorted(fs_zhp,
			    snapspec_cb, &ssa);
			if (ret == 0)
				ret = err;
			if (ret == 0 && (!ssa.ssa_seenfirst ||
			    (ssa.ssa_last[0] != '\0' && !ssa.ssa_seenlast))) {
				ret = ENOENT;
			}
		} else {
			char snapname[ZFS_MAX_DATASET_NAME_LEN];
			zfs_handle_t *snap_zhp;
			(void) snprintf(snapname, sizeof (snapname), "%s@%s",
			    zfs_get_name(fs_zhp), comma_separated);
			snap_zhp = make_dataset_handle(fs_zhp->zfs_hdl,
			    snapname);
			if (snap_zhp == NULL) {
				ret = ENOENT;
				continue;
			}
			err = func(snap_zhp, arg);
			if (ret == 0)
				ret = err;
		}
	}

	free(buf);
	return (ret);
}

/*
 * Iterate over all children, snapshots and filesystems
 */
int
zfs_iter_children(zfs_handle_t *zhp, zfs_iter_f func, void *data)
{
	int ret;

	if ((ret = zfs_iter_filesystems(zhp, func, data)) != 0)
		return (ret);

	return (zfs_iter_snapshots(zhp, B_FALSE, func, data));
}


typedef struct iter_stack_frame {
	struct iter_stack_frame *next;
	zfs_handle_t *zhp;
} iter_stack_frame_t;

typedef struct iter_dependents_arg {
	boolean_t first;
	boolean_t allowrecursion;
	iter_stack_frame_t *stack;
	zfs_iter_f func;
	void *data;
} iter_dependents_arg_t;

static int
iter_dependents_cb(zfs_handle_t *zhp, void *arg)
{
	iter_dependents_arg_t *ida = arg;
	int err = 0;
	boolean_t first = ida->first;
	ida->first = B_FALSE;

	if (zhp->zfs_type == ZFS_TYPE_SNAPSHOT) {
		err = zfs_iter_clones(zhp, iter_dependents_cb, ida);
	} else if (zhp->zfs_type != ZFS_TYPE_BOOKMARK) {
		iter_stack_frame_t isf;
		iter_stack_frame_t *f;

		/*
		 * check if there is a cycle by seeing if this fs is already
		 * on the stack.
		 */
		for (f = ida->stack; f != NULL; f = f->next) {
			if (f->zhp->zfs_dmustats.dds_guid ==
			    zhp->zfs_dmustats.dds_guid) {
				if (ida->allowrecursion) {
					zfs_close(zhp);
					return (0);
				} else {
					zfs_error_aux(zhp->zfs_hdl,
					    dgettext(TEXT_DOMAIN,
					    "recursive dependency at '%s'"),
					    zfs_get_name(zhp));
					err = zfs_error(zhp->zfs_hdl,
					    EZFS_RECURSIVE,
					    dgettext(TEXT_DOMAIN,
					    "cannot determine dependent "
					    "datasets"));
					zfs_close(zhp);
					return (err);
				}
			}
		}

		isf.zhp = zhp;
		isf.next = ida->stack;
		ida->stack = &isf;
		err = zfs_iter_filesystems(zhp, iter_dependents_cb, ida);
		if (err == 0) {
			err = zfs_iter_snapshots(zhp, B_FALSE,
			    iter_dependents_cb, ida);
		}
		ida->stack = isf.next;
	}

	if (!first && err == 0)
		err = ida->func(zhp, ida->data);
	else
		zfs_close(zhp);

	return (err);
}

int
zfs_iter_dependents(zfs_handle_t *zhp, boolean_t allowrecursion,
    zfs_iter_f func, void *data)
{
	iter_dependents_arg_t ida;
	ida.allowrecursion = allowrecursion;
	ida.stack = NULL;
	ida.func = func;
	ida.data = data;
	ida.first = B_TRUE;
	return (iter_dependents_cb(zfs_handle_dup(zhp), &ida));
}