2 .\" SPDX-License-Identifier: BSD-2-Clause
4 .\" Copyright (c) 2017 Kyle Kneitinger
5 .\" Copyright (c) 2018 Kyle Evans <kevans@FreeBSD.org>
7 .\" Redistribution and use in source and binary forms, with or without
8 .\" modification, are permitted provided that the following conditions
10 .\" 1. Redistributions of source code must retain the above copyright
11 .\" notice, this list of conditions and the following disclaimer.
12 .\" 2. Redistributions in binary form must reproduce the above copyright
13 .\" notice, this list of conditions and the following disclaimer in the
14 .\" documentation and/or other materials provided with the distribution.
16 .\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 .\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 .\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 .\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 .\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 .Nd library for creating, destroying and modifying ZFS boot environments
38 .Ft "libbe_handle_t *hdl" Ns
39 .Fn libbe_init "const char *be_root"
42 .Fn libbe_close "libbe_handle_t *hdl"
45 .Fn be_active_name "libbe_handle_t *hdl"
48 .Fn be_active_path "libbe_handle_t *hdl"
51 .Fn be_nextboot_name "libbe_handle_t *hdl"
54 .Fn be_nextboot_path "libbe_handle_t *hdl"
57 .Fn be_root_path "libbe_handle_t *hdl"
60 .Fn be_snapshot "libbe_handle_t *hdl" "const char *be_name" "const char *snap_name" "bool recursive" "char *result"
63 .Fn be_is_auto_snapshot_name "libbe_handle_t *hdl" "const char *snap"
66 .Fn be_create "libbe_handle_t *hdl" "const char *be_name"
69 .Fn be_create_depth "libbe_handle_t *hdl" "const char *be_name" "const char *snap" "int depth"
72 .Fn be_create_from_existing "libbe_handle_t *hdl" "const char *be_name" "const char *be_origin"
75 .Fn be_create_from_existing_snap "libbe_handle_t *hdl" "const char *be_name" "const char *snap"
78 .Fn be_rename "libbe_handle_t *hdl" "const char *be_old" "const char *be_new"
81 .Fn be_activate "libbe_handle_t *hdl" "const char *be_name" "bool temporary"
84 .Fn be_deactivate "libbe_handle_t *hdl" "const char *be_name" "bool temporary"
87 .Fn be_destroy "libbe_handle_t *hdl" "const char *be_name" "int options"
90 .Fn be_nicenum "uint64_t num" "char *buf" "size_t bufsz"
92 .\" TODO: Write up of mount options
94 .\" BE_MNT_FORCE = 1 << 0,
95 .\" BE_MNT_DEEP = 1 << 1,
98 .Fn be_mount "libbe_handle_t *hdl" "const char *be_name" "const char *mntpoint" "int flags" "char *result"
101 .Fn be_mounted_at "libbe_handle_t *hdl" "const char *path" "nvlist_t *details"
104 .Fn be_unmount "libbe_handle_t *hdl" "const char *be_name" "int flags"
107 .Fn libbe_errno "libbe_handle_t *hdl"
110 .Fn libbe_error_description "libbe_handle_t *hdl"
113 .Fn libbe_print_on_error "libbe_handle_t *hdl" "bool doprint"
116 .Fn be_root_concat "libbe_handle_t *hdl" "const char *be_name" "char *result"
119 .Fn be_validate_name "libbe_handle_t *hdl" "const char *be_name"
122 .Fn be_validate_snap "libbe_handle_t *hdl" "const char *snap"
125 .Fn be_exists "libbe_handle_t *hdl" "const char *be_name"
128 .Fn be_export "libbe_handle_t *hdl" "const char *be_name" "int fd"
131 .Fn be_import "libbe_handle_t *hdl" "const char *be_name" "int fd"
134 .Fn be_prop_list_alloc "nvlist_t **prop_list"
137 .Fn be_get_bootenv_props "libbe_handle_t *hdl" "nvlist_t *be_list"
140 .Fn be_get_dataset_props "libbe_handle_t *hdl" "const char *ds_name" "nvlist_t *props"
143 .Fn be_get_dataset_snapshots "libbe_handle_t *hdl" "const char *ds_name" "nvlist_t *snap_list"
146 .Fn be_prop_list_free "nvlist_t *prop_list"
149 interfaces with libzfs to provide a set of functions for various operations
150 regarding ZFS boot environments, including "deep" boot environments in which
151 a boot environment has child datasets.
153 A context structure is passed to each function, allowing for a small amount
154 of state to be retained, such as errors from previous operations.
156 may be configured to print the corresponding error message to
158 when an error is encountered with
159 .Fn libbe_print_on_error .
161 All functions returning an
163 return 0 on success, or a
165 errno otherwise as described in
170 function takes an optional BE root and initializes
173 .Vt "libbe_handle_t *"
177 If a BE root is supplied,
179 will only operate out of that pool and BE root.
180 An error may occur if:
186 are not on the same filesystem and device,
188 libzfs fails to initialize,
190 The system has not been properly booted with a ZFS boot
194 fails to open the zpool the active boot environment resides on, or
197 fails to locate the boot environment that is currently mounted.
202 function frees all resources previously acquired in
204 invalidating the handle in the process.
208 function returns the name of the currently booted boot environment.
209 This boot environment may not belong to the same BE root as the root libbe
214 function returns the full path of the currently booted boot environment.
215 This boot environment may not belong to the same BE root as the root libbe
220 function returns the name of the boot environment that will be active on reboot.
224 function returns the full path of the boot environment that will be
229 function returns the boot environment root path.
233 function creates a snapshot of
239 may be used, indicating that
241 should derive the snapshot name from the current date and time.
246 will recursively snapshot the dataset.
251 then it will be populated with the final
252 .Dq Fa be_name Ns @ Ns Fa snap_name .
255 .Fn be_is_auto_snapshot_name
256 function is used to determine if the given snapshot name matches the format that
259 function will use by default if it is not given a snapshot name to use.
262 if the name matches the format, and
268 function creates a boot environment with the given name.
269 The new boot environment will be created from a recursive snapshot of the
270 currently booted boot environment.
274 function creates a boot environment with the given name from an existing
276 The depth parameter specifies the depth of recursion that will be cloned from
277 the existing snapshot.
278 A depth of '0' is no recursion and '-1' is unlimited (i.e., a recursive boot
282 .Fn be_create_from_existing
283 function creates a boot environment with the given name from the name of an
284 existing boot environment.
285 A recursive snapshot will be made of the origin boot environment, and the new
286 boot environment will be created from that.
289 .Fn be_create_from_existing_snap
290 function creates a recursive boot environment with the given name from an
295 function renames a boot environment without unmounting it, as if renamed with
298 argument were passed to
304 function makes a boot environment active on the next boot.
307 flag is set, then it will be active for the next boot only, as done by
312 function deactivates a boot environment.
315 flag is set, then it will cause removal of boot once configuration, set by
323 function will set zfs
330 function will recursively destroy the given boot environment.
331 It will not destroy a mounted boot environment unless the
336 .Dv BE_DESTROY_ORIGIN
341 function will destroy the origin snapshot to this boot environment as well.
347 in a traditional ZFS humanized format, similar to
348 .Xr humanize_number 3 .
349 This function effectively proxies
355 function will mount the given boot environment.
360 a mount point will be generated in
368 it should be large enough to accommodate
370 including the null terminator.
371 the final mount point will be copied into it.
382 function will check if there is a boot environment mounted at the given
388 it will be populated with a list of the mounted dataset's properties.
389 This list of properties matches the properties collected by
390 .Fn be_get_bootenv_props .
394 function will unmount the given boot environment.
410 .Fn libbe_error_description
411 function returns a string description of the currently set
416 .Fn libbe_print_on_error
417 function will change whether or not
419 prints the description of any encountered error to
426 function will concatenate the boot environment root and the given boot
427 environment name into
432 function will validate the given boot environment name for both length
433 restrictions as well as valid character restrictions.
434 This function does not set the internal library error state.
438 function will validate the given snapshot name.
439 The snapshot must have a valid name, exist, and have a mountpoint of
441 This function does not set the internal library error state.
445 function will check whether the given boot environment exists and has a
448 This function does not set the internal library error state, but will return
449 the appropriate error.
453 function will export the given boot environment to the file specified by
455 A snapshot will be created of the boot environment prior to export.
459 function will import the boot environment in the file specified by
465 .Fn be_prop_list_alloc
466 function allocates a property list suitable for passing to
467 .Fn be_get_bootenv_props ,
468 .Fn be_get_dataset_props ,
470 .Fn be_get_dataset_snapshots .
471 It should be freed later by
472 .Fa be_prop_list_free .
475 .Fn be_get_bootenv_props
476 function will populate
480 of boot environment names paired with an
483 The following properties are currently collected as appropriate:
484 .Bl -column "Returned name"
485 .It Sy Returned name Ta Sy Description
487 .It name Ta Boot environment name
488 .It mounted Ta Current mount point
489 .It mountpoint Ta Do mountpoint Dc property
490 .It origin Ta Do origin Dc property
491 .It creation Ta Do creation Dc property
492 .It active Ta Currently booted environment
493 .It used Ta Literal Do used Dc property
494 .It usedds Ta Literal Do usedds Dc property
495 .It usedsnap Ta Literal Do usedrefreserv Dc property
496 .It referenced Ta Literal Do referenced Dc property
497 .It nextboot Ta Active on next boot
506 returned values will always be present.
507 All other properties may be omitted if not available.
510 .Fn be_get_dataset_props
511 function will get properties of the specified dataset.
513 is populated directly with a list of the properties as returned by
514 .Fn be_get_bootenv_props .
517 .Fn be_get_dataset_snapshots
518 function will retrieve all snapshots of the given dataset.
520 will be populated with a list of
522 exactly as specified by
523 .Fn be_get_bootenv_props .
526 .Fn be_prop_list_free
527 function will free the property list.
529 Upon error, one of the following values will be returned:
530 .Bl -bullet -offset indent -compact
581 .An Kyle Kneitinger (kneitinger) Aq Mt kyle@kneit.in
582 as a 2017 Google Summer of Code project, with
583 .An Allan Jude (allanjude) Aq Mt allanjude@freebsd.org
586 Kyle Kneitinger, mentored as above.
588 Post-GSoC changes were written by
589 .An Kyle Evans (kevans) Aq Mt kevans@freebsd.org .