2 .\" SPDX-License-Identifier: BSD-2-Clause-FreeBSD
4 .\" Copyright (c) 2017 Kyle Kneitinger
5 .\" All rights reserved.
6 .\" Copyright (c) 2018 Kyle Evans <kevans@FreeBSD.org>
8 .\" Redistribution and use in source and binary forms, with or without
9 .\" modification, are permitted provided that the following conditions
11 .\" 1. Redistributions of source code must retain the above copyright
12 .\" notice, this list of conditions and the following disclaimer.
13 .\" 2. Redistributions in binary form must reproduce the above copyright
14 .\" notice, this list of conditions and the following disclaimer in the
15 .\" documentation and/or other materials provided with the distribution.
17 .\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18 .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 .\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21 .\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 .\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 .\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36 .Nd library for creating, destroying and modifying ZFS boot environments
41 .Ft "libbe_handle_t *hdl" Ns
42 .Fn libbe_init "const char *be_root"
45 .Fn libbe_close "libbe_handle_t *hdl"
48 .Fn be_active_name "libbe_handle_t *hdl"
51 .Fn be_active_path "libbe_handle_t *hdl"
54 .Fn be_nextboot_name "libbe_handle_t *hdl"
57 .Fn be_nextboot_path "libbe_handle_t *hdl"
60 .Fn be_root_path "libbe_handle_t *hdl"
63 .Fn be_create "libbe_handle_t *hdl" "const char *be_name"
66 .Fn be_create_depth "libbe_handle_t *hdl" "const char *be_name" "const char *snap" "int depth"
69 .Fn be_create_from_existing "libbe_handle_t *hdl" "const char *be_name" "const char *be_origin"
72 .Fn be_create_from_existing_snap "libbe_handle_t *hdl" "const char *be_name" "const char *snap"
75 .Fn be_rename "libbe_handle_t *hdl" "const char *be_old" "const char *be_new"
78 .Fn be_activate "libbe_handle_t *hdl" "const char *be_name" "bool temporary"
80 .Fn be_destroy "libbe_handle_t *hdl" "const char *be_name" "int options"
83 .Fn be_nicenum "uint64_t num" "char *buf" "size_t bufsz"
85 .\" TODO: Write up of mount options
87 .\" BE_MNT_FORCE = 1 << 0,
88 .\" BE_MNT_DEEP = 1 << 1,
91 .Fn be_mount "libbe_handle_t *hdl" "char *be_name" "char *mntpoint" "int flags" "char *result"
94 .Fn be_mounted_at "libbe_handle_t *hdl" "const char *path" "nvlist_t *details"
97 .Fn be_unmount "libbe_handle_t *hdl" "char *be_name" "int flags"
100 .Fn libbe_errno "libbe_handle_t *hdl"
103 .Fn libbe_error_description "libbe_handle_t *hdl"
106 .Fn libbe_print_on_error "libbe_handle_t *hdl" "bool doprint"
109 .Fn be_root_concat "libbe_handle_t *hdl" "const char *be_name" "char *result"
112 .Fn be_validate_name "libbe_handle_t *hdl" "const char *be_name"
115 .Fn be_validate_snap "libbe_handle_t *hdl" "const char *snap"
118 .Fn be_exists "libbe_handle_t *hdl" "char *be_name"
121 .Fn be_export "libbe_handle_t *hdl" "const char *be_name" "int fd"
124 .Fn be_import "libbe_handle_t *hdl" "const char *be_name" "int fd"
127 .Fn be_prop_list_alloc "nvlist_t **prop_list"
130 .Fn be_get_bootenv_props "libbe_handle_t *hdl" "nvlist_t *be_list"
133 .Fn be_get_dataset_props "libbe_handle_t *hdl" "const char *ds_name" "nvlist_t *props"
136 .Fn be_get_dataset_snapshots "libbe_handle_t *hdl" "const char *ds_name" "nvlist_t *snap_list"
139 .Fn be_prop_list_free "nvlist_t *prop_list"
142 interfaces with libzfs to provide a set of functions for various operations
143 regarding ZFS boot environments including "deep" boot environments in which
144 a boot environments has child datasets.
146 A context structure is passed to each function, allowing for a small amount
147 of state to be retained, such as errors from previous operations.
149 may be configured to print the corresponding error message to
151 when an error is encountered with
152 .Fn libbe_print_on_error .
154 All functions returning an
156 return 0 on success, or a
158 errno otherwise as described in
163 function takes an optional BE root and initializes
166 .Vt "libbe_handle_t *"
170 If a BE root is supplied,
172 will only operate out of that pool and BE root.
173 An error may occur if:
175 .It /boot and / are not on the same filesystem and device,
176 .It libzfs fails to initialize,
177 .It The system has not been properly booted with a ZFS boot
180 fails to open the zpool the active boot environment resides on, or
182 fails to locate the boot environment that is currently mounted.
187 function frees all resources previously acquired in
189 invalidating the handle in the process.
193 function returns the name of the currently booted boot environment.
194 This boot environment may not belong to the same BE root as the root libbe
199 function returns the full path of the currently booted boot environment.
200 This boot environment may not belong to the same BE root as the root libbe
205 function returns the name of the boot environment that will be active on reboot.
209 function returns the full path of the boot environment that will be
214 function returns the boot environment root path.
218 function creates a boot environment with the given name.
219 The new boot environment will be created from a recursive snapshot of the
220 currently booted boot environment.
224 function creates a boot environment with the given name from an existing
226 The depth parameter specifies the depth of recursion that will be cloned from
227 the existing snapshot.
228 A depth of '0' is no recursion and '-1' is unlimited (i.e., a recursive boot
232 .Fn be_create_from_existing
233 function creates a boot environment with the given name from the name of an
234 existing boot environment.
235 A recursive snapshot will be made of the origin boot environment, and the new
236 boot environment will be created from that.
239 .Fn be_create_from_existing_snap
240 function creates a recursive boot environment with the given name from an
245 function renames a boot environment without unmounting it, as if renamed with
248 argument were passed to
254 function makes a boot environment active on the next boot.
257 flag is set, then it will be active for the next boot only, as done by
259 Next boot functionality is currently only available when booting in x86 BIOS
264 function will recursively destroy the given boot environment.
265 It will not destroy a mounted boot environment unless the
270 .Dv BE_DESTROY_ORIGIN
275 function will destroy the origin snapshot to this boot environment as well.
281 in a traditional ZFS humanized format, similar to
282 .Xr humanize_number 3 .
283 This function effectively proxies
289 function will mount the given boot environment.
294 a mount point will be generated in
302 it should be large enough to accommodate
304 including the null terminator.
305 the final mount point will be copied into it.
316 function will check if there is a boot environment mounted at the given
322 it will be populated with a list of the mounted dataset's properties.
323 This list of properties matches the properties collected by
324 .Fn be_get_bootenv_props .
328 function will unmount the given boot environment.
344 .Fn libbe_error_description
345 function returns a string description of the currently set
350 .Fn libbe_print_on_error
351 function will change whether or not
353 prints the description of any encountered error to
360 function will concatenate the boot environment root and the given boot
361 environment name into
366 function will validate the given boot environment name for both length
367 restrictions as well as valid character restrictions.
368 This function does not set the internal library error state.
372 function will validate the given snapshot name.
373 The snapshot must have a valid name, exist, and have a mountpoint of
375 This function does not set the internal library error state.
379 function will check whether the given boot environment exists and has a
382 This function does not set the internal library error state, but will return
383 the appropriate error.
387 function will export the given boot environment to the file specified by
389 A snapshot will be created of the boot environment prior to export.
393 function will import the boot environment in the file specified by
399 .Fn be_prop_list_alloc
400 function allocates a property list suitable for passing to
401 .Fn be_get_bootenv_props ,
402 .Fn be_get_dataset_props ,
404 .Fn be_get_dataset_snapshots .
405 It should be freed later by
406 .Fa be_prop_list_free .
409 .Fn be_get_bootenv_props
410 function will populate
414 of boot environment names paired with an
417 The following properties are currently collected as appropriate:
418 .Bl -column "Returned name"
419 .It Sy Returned name Ta Sy Description
421 .It name Ta Boot environment name
422 .It mounted Ta Current mount point
423 .It mountpoint Ta Do mountpoint Dc property
424 .It origin Ta Do origin Dc property
425 .It creation Ta Do creation Dc property
426 .It active Ta Currently booted environment
427 .It used Ta Literal Do used Dc property
428 .It usedds Ta Literal Do usedds Dc property
429 .It usedsnap Ta Literal Do usedrefreserv Dc property
430 .It referenced Ta Literal Do referenced Dc property
431 .It nextboot Ta Active on next boot
440 returned values will always be present.
441 All other properties may be omitted if not available.
444 .Fn be_get_dataset_props
445 function will get properties of the specified dataset.
447 is populated directly with a list of the properties as returned by
448 .Fn be_get_bootenv_props .
451 .Fn be_get_dataset_snapshots
452 function will retrieve all snapshots of the given dataset.
454 will be populated with a list of
456 exactly as specified by
457 .Fn be_get_bootenv_props .
460 .Fn be_prop_list_free
461 function will free the property list.
463 Upon error, one of the following values will be returned:
464 .Bl -dash -offset indent -compact
512 and its corresponding command,
514 were written as a 2017 Google Summer of Code project with Allan Jude serving
516 Later work was done by
517 .An Kyle Evans Aq Mt kevans@FreeBSD.org .