2 .\" SPDX-License-Identifier: BSD-2-Clause-FreeBSD
4 .\" Copyright (c) 2017 Kyle Kneitinger
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6 .\" Copyright (c) 2018 Kyle Evans <kevans@FreeBSD.org>
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36 .Nd library for creating, destroying and modifying ZFS boot environments
41 .Ft "libbe_handle_t *hdl" Ns
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_from_existing "libbe_handle_t *hdl" "const char *be_name" "const char *be_origin"
69 .Fn be_create_from_existing_snap "libbe_handle_t *hdl" "const char *be_name" "const char *snap"
72 .Fn be_rename "libbe_handle_t *hdl" "const char *be_old" "const char *be_new"
75 .Fn be_activate "libbe_handle_t *hdl" "const char *be_name" "bool temporary"
77 .Fn be_destroy "libbe_handle_t *hdl" "const char *be_name" "int options"
80 .Fn be_nicenum "uint64_t num" "char *buf" "size_t bufsz"
82 .\" TODO: Write up of mount options
84 .\" BE_MNT_FORCE = 1 << 0,
85 .\" BE_MNT_DEEP = 1 << 1,
88 .Fn be_mount "libbe_handle_t *hdl" "char *be_name" "char *mntpoint" "int flags" "char *result"
91 .Fn be_mounted_at "libbe_handle_t *hdl" "const char *path" "nvlist_t *details"
94 .Fn be_unmount "libbe_handle_t *hdl" "char *be_name" "int flags"
97 .Fn libbe_errno "libbe_handle_t *hdl"
100 .Fn libbe_error_description "libbe_handle_t *hdl"
103 .Fn libbe_print_on_error "libbe_handle_t *hdl" "bool doprint"
106 .Fn be_root_concat "libbe_handle_t *hdl" "const char *be_name" "char *result"
109 .Fn be_validate_name "libbe_handle_t *hdl" "const char *be_name"
112 .Fn be_validate_snap "libbe_handle_t *hdl" "const char *snap"
115 .Fn be_exists "libbe_handle_t *hdl" "char *be_name"
118 .Fn be_export "libbe_handle_t *hdl" "const char *be_name" "int fd"
121 .Fn be_import "libbe_handle_t *hdl" "const char *be_name" "int fd"
124 .Fn be_prop_list_alloc "nvlist_t **prop_list"
127 .Fn be_get_bootenv_props "libbe_handle_t *hdl" "nvlist_t *be_list"
130 .Fn be_get_dataset_props "libbe_handle_t *hdl" "const char *ds_name" "nvlist_t *props"
133 .Fn be_get_dataset_snapshots "libbe_handle_t *hdl" "const char *ds_name" "nvlist_t *snap_list"
136 .Fn be_prop_list_free "nvlist_t *prop_list"
139 interfaces with libzfs to provide a set of functions for various operations
140 regarding ZFS boot environments including "deep" boot environments in which
141 a boot environments has child datasets.
143 A context structure is passed to each function, allowing for a small amount
144 of state to be retained, such as errors from previous operations.
146 may be configured to print the corresponding error message to
148 when an error is encountered with
149 .Fn libbe_print_on_error .
151 All functions returning an
153 return 0 on success, or a
155 errno otherwise as described in
163 .Vt "libbe_handle_t *"
167 An error may occur if:
169 .It /boot and / are not on the same filesystem and device,
170 .It libzfs fails to initialize,
171 .It The system has not been properly booted with a ZFS boot
174 fails to open the zpool the active boot environment resides on, or
176 fails to locate the boot environment that is currently mounted.
181 function frees all resources previously acquired in
183 invalidating the handle in the process.
187 function returns the name of the currently booted boot environment,
191 function returns the full path of the currently booted boot environment.
195 function returns the name of the boot environment that will be active on reboot.
199 function returns the full path of the boot environment that will be
204 function returns the boot environment root path.
208 function creates a boot environment with the given name.
209 It will be created from a snapshot of the currently booted boot environment.
212 .Fn be_create_from_existing
213 function creates a boot environment with the given name from the name of an
214 existing boot environment.
215 A snapshot will be made of the base boot environment, and the new boot
216 environment will be created from that.
219 .Fn be_create_from_existing_snap
220 function creates a boot environment with the given name from an existing
225 function renames a boot environment.
229 function makes a boot environment active on the next boot.
232 flag is set, then it will be active for the next boot only, as done by
234 Next boot functionality is currently only available when booting in x86 BIOS
239 function will recursively destroy the given boot environment.
240 It will not destroy a mounted boot environment unless the
249 in a traditional ZFS humanized format, similar to
250 .Xr humanize_number 3 .
251 This function effectively proxies
257 function will mount the given boot environment.
262 a mount point will be generated in
270 it should be large enough to accommodate
272 including the null terminator.
273 the final mount point will be copied into it.
284 function will check if there is a boot environment mounted at the given
290 it will be populated with a list of the mounted dataset's properties.
291 This list of properties matches the properties collected by
292 .Fn be_get_bootenv_props .
296 function will unmount the given boot environment.
312 .Fn libbe_error_description
313 function returns a string description of the currently set
318 .Fn libbe_print_on_error
319 function will change whether or not
321 prints the description of any encountered error to
328 function will concatenate the boot environment root and the given boot
329 environment name into
334 function will validate the given boot environment name for both length
335 restrictions as well as valid character restrictions.
336 This function does not set the internal library error state.
340 function will validate the given snapshot name.
341 The snapshot must have a valid name, exist, and have a mountpoint of
343 This function does not set the internal library error state.
347 function will check whether the given boot environment exists and has a
353 function will export the given boot environment to the file specified by
355 A snapshot will be created of the boot environment prior to export.
359 function will import the boot environment in the file specified by
365 .Fn be_prop_list_alloc
366 function allocates a property list suitable for passing to
367 .Fn be_get_bootenv_props ,
368 .Fn be_get_dataset_props ,
370 .Fn be_get_dataset_snapshots .
371 It should be freed later by
372 .Fa be_prop_list_free .
375 .Fn be_get_bootenv_props
376 function will populate
380 of boot environment names paired with an
383 The following properties are currently collected as appropriate:
384 .Bl -column "Returned name"
385 .It Sy Returned name Ta Sy Description
387 .It name Ta Boot environment name
388 .It mounted Ta Current mount point
389 .It mountpoint Ta Do mountpoint Dc property
390 .It origin Ta Do origin Dc property
391 .It creation Ta Do creation Dc property
392 .It active Ta Currently booted environment
393 .It used Ta Literal Do used Dc property
394 .It usedds Ta Literal Do usedds Dc property
395 .It usedsnap Ta Literal Do usedrefreserv Dc property
396 .It referenced Ta Literal Do referenced Dc property
397 .It nextboot Ta Active on next boot
406 returned values will always be present.
407 All other properties may be omitted if not available.
410 .Fn be_get_dataset_props
411 function will get properties of the specified dataset.
413 is populated directly with a list of the properties as returned by
414 .Fn be_get_bootenv_props .
417 .Fn be_get_dataset_snapshots
418 function will retrieve all snapshots of the given dataset.
420 will be populated with a list of
422 exactly as specified by
423 .Fn be_get_bootenv_props .
426 .Fn be_prop_list_free
427 function will free the property list.
429 Upon error, one of the following values will be returned.
430 .\" TODO: make each entry on its own line.
431 .Bd -ragged -offset indent
457 and its corresponding command,
459 were written as a 2017 Google Summer of Code project with Allan Jude serving
461 Later work was done by
462 .An Kyle Evans Aq Mt kevans@FreeBSD.org .