xref: /freebsd/sys/contrib/openzfs/contrib/initramfs/scripts/zfs (revision bdd1243df58e60e85101c09001d9812a789b6bc4)
1# ZFS boot stub for initramfs-tools.
2#
3# In the initramfs environment, the /init script sources this stub to
4# override the default functions in the /scripts/local script.
5#
6# Enable this by passing boot=zfs on the kernel command line.
7#
8# $quiet, $root, $rpool, $bootfs come from the cmdline:
9# shellcheck disable=SC2154
10
11# Source the common functions
12. /etc/zfs/zfs-functions
13
14# Start interactive shell.
15# Use debian's panic() if defined, because it allows to prevent shell access
16# by setting panic in cmdline (e.g. panic=0 or panic=15).
17# See "4.5 Disable root prompt on the initramfs" of Securing Debian Manual:
18# https://www.debian.org/doc/manuals/securing-debian-howto/ch4.en.html
19shell() {
20	if command -v panic > /dev/null 2>&1; then
21		panic
22	else
23		/bin/sh
24	fi
25}
26
27# This runs any scripts that should run before we start importing
28# pools and mounting any filesystems.
29pre_mountroot()
30{
31	if command -v run_scripts > /dev/null 2>&1
32	then
33		if [ -f "/scripts/local-top" ] || [ -d "/scripts/local-top" ]
34		then
35			[ "$quiet" != "y" ] && \
36			    zfs_log_begin_msg "Running /scripts/local-top"
37			run_scripts /scripts/local-top
38			[ "$quiet" != "y" ] && zfs_log_end_msg
39		fi
40
41	  if [ -f "/scripts/local-premount" ] || [ -d "/scripts/local-premount" ]
42	  then
43			[ "$quiet" != "y" ] && \
44			    zfs_log_begin_msg "Running /scripts/local-premount"
45			run_scripts /scripts/local-premount
46			[ "$quiet" != "y" ] && zfs_log_end_msg
47		fi
48	fi
49}
50
51# If plymouth is available, hide the splash image.
52disable_plymouth()
53{
54	if [ -x /bin/plymouth ] && /bin/plymouth --ping
55	then
56		/bin/plymouth hide-splash >/dev/null 2>&1
57	fi
58}
59
60# Get a ZFS filesystem property value.
61get_fs_value()
62{
63	fs="$1"
64	value=$2
65
66	"${ZFS}" get -H -ovalue "$value" "$fs" 2> /dev/null
67}
68
69# Find the 'bootfs' property on pool $1.
70# If the property does not contain '/', then ignore this
71# pool by exporting it again.
72find_rootfs()
73{
74	pool="$1"
75
76	# If 'POOL_IMPORTED' isn't set, no pool imported and therefore
77	# we won't be able to find a root fs.
78	[ -z "${POOL_IMPORTED}" ] && return 1
79
80	# If it's already specified, just keep it mounted and exit
81	# User (kernel command line) must be correct.
82	if [ -n "${ZFS_BOOTFS}" ] && [ "${ZFS_BOOTFS}" != "zfs:AUTO" ]; then
83		return 0
84	fi
85
86	# Not set, try to find it in the 'bootfs' property of the pool.
87	# NOTE: zpool does not support 'get -H -ovalue bootfs'...
88	ZFS_BOOTFS=$("${ZPOOL}" list -H -obootfs "$pool")
89
90	# Make sure it's not '-' and that it starts with /.
91	if [ "${ZFS_BOOTFS}" != "-" ] && \
92		get_fs_value "${ZFS_BOOTFS}" mountpoint | grep -q '^/$'
93	then
94		# Keep it mounted
95		POOL_IMPORTED=1
96		return 0
97	fi
98
99	# Not boot fs here, export it and later try again..
100	"${ZPOOL}" export "$pool"
101	POOL_IMPORTED=
102	ZFS_BOOTFS=
103	return 1
104}
105
106# Support function to get a list of all pools, separated with ';'
107find_pools()
108{
109	pools=$("$@" 2> /dev/null | \
110		sed -Ee '/pool:|^[a-zA-Z0-9]/!d' -e 's@.*: @@' | \
111		tr '\n' ';')
112
113	echo "${pools%%;}" # Return without the last ';'.
114}
115
116# Get a list of all available pools
117get_pools()
118{
119	if [ -n "${ZFS_POOL_IMPORT}" ]; then
120		echo "$ZFS_POOL_IMPORT"
121		return 0
122	fi
123
124	# Get the base list of available pools.
125	available_pools=$(find_pools "$ZPOOL" import)
126
127	# Just in case - seen it happen (that a pool isn't visible/found
128	# with a simple "zpool import" but only when using the "-d"
129	# option or setting ZPOOL_IMPORT_PATH).
130	if [ -d "/dev/disk/by-id" ]
131	then
132		npools=$(find_pools "$ZPOOL" import -d /dev/disk/by-id)
133		if [ -n "$npools" ]
134		then
135			# Because we have found extra pool(s) here, which wasn't
136			# found 'normally', we need to force USE_DISK_BY_ID to
137			# make sure we're able to actually import it/them later.
138			USE_DISK_BY_ID='yes'
139
140			if [ -n "$available_pools" ]
141			then
142				# Filter out duplicates (pools found with the simple
143				# "zpool import" but which is also found with the
144				# "zpool import -d ...").
145				npools=$(echo "$npools" | sed "s,$available_pools,,")
146
147				# Add the list to the existing list of
148				# available pools
149				available_pools="$available_pools;$npools"
150			else
151				available_pools="$npools"
152			fi
153		fi
154	fi
155
156	# Filter out any exceptions...
157	if [ -n "$ZFS_POOL_EXCEPTIONS" ]
158	then
159		found=""
160		apools=""
161		OLD_IFS="$IFS" ; IFS=";"
162
163		for pool in $available_pools
164		do
165			for exception in $ZFS_POOL_EXCEPTIONS
166			do
167				[ "$pool" = "$exception" ] && continue 2
168				found="$pool"
169			done
170
171			if [ -n "$found" ]
172			then
173				if [ -n "$apools" ]
174				then
175					apools="$apools;$pool"
176				else
177					apools="$pool"
178				fi
179			fi
180		done
181
182		IFS="$OLD_IFS"
183		available_pools="$apools"
184	fi
185
186	# Return list of available pools.
187	echo "$available_pools"
188}
189
190# Import given pool $1
191import_pool()
192{
193	pool="$1"
194
195	# Verify that the pool isn't already imported
196	# Make as sure as we can to not require '-f' to import.
197	"${ZPOOL}" get -H -o value name,guid 2>/dev/null | grep -Fxq "$pool" && return 0
198
199	# For backwards compatibility, make sure that ZPOOL_IMPORT_PATH is set
200	# to something we can use later with the real import(s). We want to
201	# make sure we find all by* dirs, BUT by-vdev should be first (if it
202	# exists).
203	if [ -n "$USE_DISK_BY_ID" ] && [ -z "$ZPOOL_IMPORT_PATH" ]
204	then
205		dirs="$(for dir in /dev/disk/by-*
206		do
207			# Ignore by-vdev here - we want it first!
208			echo "$dir" | grep -q /by-vdev && continue
209			[ ! -d "$dir" ] && continue
210
211			printf "%s" "$dir:"
212		done | sed 's,:$,,g')"
213
214		if [ -d "/dev/disk/by-vdev" ]
215		then
216			# Add by-vdev at the beginning.
217			ZPOOL_IMPORT_PATH="/dev/disk/by-vdev:"
218		fi
219
220		# ... and /dev at the very end, just for good measure.
221		ZPOOL_IMPORT_PATH="$ZPOOL_IMPORT_PATH$dirs:/dev"
222	fi
223
224	# Needs to be exported for "zpool" to catch it.
225	[ -n "$ZPOOL_IMPORT_PATH" ] && export ZPOOL_IMPORT_PATH
226
227
228	[ "$quiet" != "y" ] && zfs_log_begin_msg \
229		"Importing pool '${pool}' using defaults"
230
231	ZFS_CMD="${ZPOOL} import -N ${ZPOOL_FORCE} ${ZPOOL_IMPORT_OPTS}"
232	ZFS_STDERR="$($ZFS_CMD "$pool" 2>&1)"
233	ZFS_ERROR="$?"
234	if [ "${ZFS_ERROR}" != 0 ]
235	then
236		[ "$quiet" != "y" ] && zfs_log_failure_msg "${ZFS_ERROR}"
237
238		if [ -f "${ZPOOL_CACHE}" ]
239		then
240			[ "$quiet" != "y" ] && zfs_log_begin_msg \
241				"Importing pool '${pool}' using cachefile."
242
243			ZFS_CMD="${ZPOOL} import -c ${ZPOOL_CACHE} -N ${ZPOOL_FORCE} ${ZPOOL_IMPORT_OPTS}"
244			ZFS_STDERR="$($ZFS_CMD "$pool" 2>&1)"
245			ZFS_ERROR="$?"
246		fi
247
248		if [ "${ZFS_ERROR}" != 0 ]
249		then
250			[ "$quiet" != "y" ] && zfs_log_failure_msg "${ZFS_ERROR}"
251
252			disable_plymouth
253			echo ""
254			echo "Command: ${ZFS_CMD} '$pool'"
255			echo "Message: $ZFS_STDERR"
256			echo "Error: $ZFS_ERROR"
257			echo ""
258			echo "Failed to import pool '$pool'."
259			echo "Manually import the pool and exit."
260			shell
261		fi
262	fi
263
264	[ "$quiet" != "y" ] && zfs_log_end_msg
265
266	POOL_IMPORTED=1
267	return 0
268}
269
270# Load ZFS modules
271# Loading a module in a initrd require a slightly different approach,
272# with more logging etc.
273load_module_initrd()
274{
275	ZFS_INITRD_PRE_MOUNTROOT_SLEEP=${ROOTDELAY:-0}
276
277	if [ "$ZFS_INITRD_PRE_MOUNTROOT_SLEEP" -gt 0 ]; then
278		[ "$quiet" != "y" ] && zfs_log_begin_msg "Delaying for up to '${ZFS_INITRD_PRE_MOUNTROOT_SLEEP}' seconds."
279	fi
280
281	START=$(/bin/date -u +%s)
282	END=$((START+ZFS_INITRD_PRE_MOUNTROOT_SLEEP))
283	while true; do
284
285		# Wait for all of the /dev/{hd,sd}[a-z] device nodes to appear.
286		if command -v wait_for_udev > /dev/null 2>&1 ; then
287			wait_for_udev 10
288		elif command -v wait_for_dev > /dev/null 2>&1 ; then
289			wait_for_dev
290		fi
291
292		#
293		# zpool import refuse to import without a valid
294		# /proc/self/mounts
295		#
296		[ ! -f /proc/self/mounts ] && mount proc /proc
297
298		# Load the module
299		if load_module "zfs"; then
300			ret=0
301			break
302		else
303			ret=1
304		fi
305
306		[ "$(/bin/date -u +%s)" -gt "$END" ] && break
307		sleep 1
308
309	done
310	if [ "$ZFS_INITRD_PRE_MOUNTROOT_SLEEP" -gt 0 ]; then
311		[ "$quiet" != "y" ] && zfs_log_end_msg
312	fi
313
314	[ "$ret" -ne 0 ] && return 1
315
316	if [ "$ZFS_INITRD_POST_MODPROBE_SLEEP" -gt 0 ] 2>/dev/null
317	then
318		if [ "$quiet" != "y" ]; then
319			zfs_log_begin_msg "Sleeping for" \
320				"$ZFS_INITRD_POST_MODPROBE_SLEEP seconds..."
321		fi
322		sleep "$ZFS_INITRD_POST_MODPROBE_SLEEP"
323		[ "$quiet" != "y" ] && zfs_log_end_msg
324	fi
325
326	return 0
327}
328
329# Mount a given filesystem
330mount_fs()
331{
332	fs="$1"
333
334	# Check that the filesystem exists
335	"${ZFS}" list -oname -tfilesystem -H "${fs}" > /dev/null 2>&1 ||  return 1
336
337	# Skip filesystems with canmount=off.  The root fs should not have
338	# canmount=off, but ignore it for backwards compatibility just in case.
339	if [ "$fs" != "${ZFS_BOOTFS}" ]
340	then
341		canmount=$(get_fs_value "$fs" canmount)
342		[ "$canmount" = "off" ] && return 0
343	fi
344
345	# Need the _original_ datasets mountpoint!
346	mountpoint=$(get_fs_value "$fs" mountpoint)
347	ZFS_CMD="mount -o zfsutil -t zfs"
348	if [ "$mountpoint" = "legacy" ] || [ "$mountpoint" = "none" ]; then
349		# Can't use the mountpoint property. Might be one of our
350		# clones. Check the 'org.zol:mountpoint' property set in
351		# clone_snap() if that's usable.
352		mountpoint1=$(get_fs_value "$fs" org.zol:mountpoint)
353		if [ "$mountpoint1" = "legacy" ] ||
354		   [ "$mountpoint1" = "none" ] ||
355		   [ "$mountpoint1" = "-" ]
356		then
357			if [ "$fs" != "${ZFS_BOOTFS}" ]; then
358				# We don't have a proper mountpoint and this
359				# isn't the root fs.
360				return 0
361			fi
362			# Don't use mount.zfs -o zfsutils for legacy mountpoint
363			if [ "$mountpoint" = "legacy" ]; then
364				ZFS_CMD="mount -t zfs"
365			fi
366			# Last hail-mary: Hope 'rootmnt' is set!
367			mountpoint=""
368		else
369			mountpoint="$mountpoint1"
370		fi
371	fi
372
373	# Possibly decrypt a filesystem using native encryption.
374	decrypt_fs "$fs"
375
376	[ "$quiet" != "y" ] && \
377	    zfs_log_begin_msg "Mounting '${fs}' on '${rootmnt}/${mountpoint}'"
378	[ -n "${ZFS_DEBUG}" ] && \
379	    zfs_log_begin_msg "CMD: '$ZFS_CMD ${fs} ${rootmnt}/${mountpoint}'"
380
381	ZFS_STDERR=$(${ZFS_CMD} "${fs}" "${rootmnt}/${mountpoint}" 2>&1)
382	ZFS_ERROR=$?
383	if [ "${ZFS_ERROR}" != 0 ]
384	then
385		[ "$quiet" != "y" ] && zfs_log_failure_msg "${ZFS_ERROR}"
386
387		disable_plymouth
388		echo ""
389		echo "Command: ${ZFS_CMD} ${fs} ${rootmnt}/${mountpoint}"
390		echo "Message: $ZFS_STDERR"
391		echo "Error: $ZFS_ERROR"
392		echo ""
393		echo "Failed to mount ${fs} on ${rootmnt}/${mountpoint}."
394		echo "Manually mount the filesystem and exit."
395		shell
396	else
397		[ "$quiet" != "y" ] && zfs_log_end_msg
398	fi
399
400	return 0
401}
402
403# Unlock a ZFS native encrypted filesystem.
404decrypt_fs()
405{
406	fs="$1"
407
408	# If pool encryption is active and the zfs command understands '-o encryption'
409	if [ "$(zpool list -H -o feature@encryption "${fs%%/*}")" = 'active' ]; then
410
411		# Determine dataset that holds key for root dataset
412		ENCRYPTIONROOT="$(get_fs_value "${fs}" encryptionroot)"
413		KEYLOCATION="$(get_fs_value "${ENCRYPTIONROOT}" keylocation)"
414
415		echo "${ENCRYPTIONROOT}" > /run/zfs_fs_name
416
417		# If root dataset is encrypted...
418		if ! [ "${ENCRYPTIONROOT}" = "-" ]; then
419			KEYSTATUS="$(get_fs_value "${ENCRYPTIONROOT}" keystatus)"
420			# Continue only if the key needs to be loaded
421			[ "$KEYSTATUS" = "unavailable" ] || return 0
422
423			# Try extensions first
424			for f in "/etc/zfs/initramfs-tools-load-key" "/etc/zfs/initramfs-tools-load-key.d/"*; do
425				[ -r "$f" ] || continue
426				(. "$f") && {
427					# Successful return and actually-loaded key: we're done
428					KEYSTATUS="$(get_fs_value "${ENCRYPTIONROOT}" keystatus)"
429					[ "$KEYSTATUS" = "unavailable" ] || return 0
430				}
431			done
432
433			# Do not prompt if key is stored noninteractively,
434			if ! [ "${KEYLOCATION}" = "prompt" ]; then
435				$ZFS load-key "${ENCRYPTIONROOT}"
436
437			# Prompt with plymouth, if active
438			elif /bin/plymouth --ping 2>/dev/null; then
439				echo "plymouth" > /run/zfs_console_askpwd_cmd
440				for _ in 1 2 3; do
441					plymouth ask-for-password --prompt "Encrypted ZFS password for ${ENCRYPTIONROOT}" | \
442						$ZFS load-key "${ENCRYPTIONROOT}" && break
443				done
444
445			# Prompt with systemd, if active
446			elif [ -e /run/systemd/system ]; then
447				echo "systemd-ask-password" > /run/zfs_console_askpwd_cmd
448				for _ in 1 2 3; do
449					systemd-ask-password --no-tty "Encrypted ZFS password for ${ENCRYPTIONROOT}" | \
450						$ZFS load-key "${ENCRYPTIONROOT}" && break
451				done
452
453			# Prompt with ZFS tty, otherwise
454			else
455				# Temporarily setting "printk" to "7" allows the prompt to appear even when the "quiet" kernel option has been used
456				echo "load-key" > /run/zfs_console_askpwd_cmd
457				read -r storeprintk _ < /proc/sys/kernel/printk
458				echo 7 > /proc/sys/kernel/printk
459				$ZFS load-key "${ENCRYPTIONROOT}"
460				echo "$storeprintk" > /proc/sys/kernel/printk
461			fi
462		fi
463	fi
464
465	return 0
466}
467
468# Destroy a given filesystem.
469destroy_fs()
470{
471	fs="$1"
472
473	[ "$quiet" != "y" ] && \
474	    zfs_log_begin_msg "Destroying '$fs'"
475
476	ZFS_CMD="${ZFS} destroy $fs"
477	ZFS_STDERR="$(${ZFS_CMD} 2>&1)"
478	ZFS_ERROR="$?"
479	if [ "${ZFS_ERROR}" != 0 ]
480	then
481		[ "$quiet" != "y" ] && zfs_log_failure_msg "${ZFS_ERROR}"
482
483		disable_plymouth
484		echo ""
485		echo "Command: $ZFS_CMD"
486		echo "Message: $ZFS_STDERR"
487		echo "Error: $ZFS_ERROR"
488		echo ""
489		echo "Failed to destroy '$fs'. Please make sure that '$fs' is not available."
490		echo "Hint: Try:  zfs destroy -Rfn $fs"
491		echo "If this dryrun looks good, then remove the 'n' from '-Rfn' and try again."
492		shell
493	else
494		[ "$quiet" != "y" ] && zfs_log_end_msg
495	fi
496
497	return 0
498}
499
500# Clone snapshot $1 to destination filesystem $2
501# Set 'canmount=noauto' and 'mountpoint=none' so that we get to keep
502# manual control over it's mounting (i.e., make sure it's not automatically
503# mounted with a 'zfs mount -a' in the init/systemd scripts).
504clone_snap()
505{
506	snap="$1"
507	destfs="$2"
508	mountpoint="$3"
509
510	[ "$quiet" != "y" ] && zfs_log_begin_msg "Cloning '$snap' to '$destfs'"
511
512	# Clone the snapshot into a dataset we can boot from
513	# + We don't want this filesystem to be automatically mounted, we
514	#   want control over this here and nowhere else.
515	# + We don't need any mountpoint set for the same reason.
516	# We use the 'org.zol:mountpoint' property to remember the mountpoint.
517	ZFS_CMD="${ZFS} clone -o canmount=noauto -o mountpoint=none"
518	ZFS_CMD="${ZFS_CMD} -o org.zol:mountpoint=${mountpoint}"
519	ZFS_CMD="${ZFS_CMD} $snap $destfs"
520	ZFS_STDERR="$(${ZFS_CMD} 2>&1)"
521	ZFS_ERROR="$?"
522	if [ "${ZFS_ERROR}" != 0 ]
523	then
524		[ "$quiet" != "y" ] && zfs_log_failure_msg "${ZFS_ERROR}"
525
526		disable_plymouth
527		echo ""
528		echo "Command: $ZFS_CMD"
529		echo "Message: $ZFS_STDERR"
530		echo "Error: $ZFS_ERROR"
531		echo ""
532		echo "Failed to clone snapshot."
533		echo "Make sure that any problems are corrected and then make sure"
534		echo "that the dataset '$destfs' exists and is bootable."
535		shell
536	else
537		[ "$quiet" != "y" ] && zfs_log_end_msg
538	fi
539
540	return 0
541}
542
543# Rollback a given snapshot.
544rollback_snap()
545{
546	snap="$1"
547
548	[ "$quiet" != "y" ] && zfs_log_begin_msg "Rollback $snap"
549
550	ZFS_CMD="${ZFS} rollback -Rf $snap"
551	ZFS_STDERR="$(${ZFS_CMD} 2>&1)"
552	ZFS_ERROR="$?"
553	if [ "${ZFS_ERROR}" != 0 ]
554	then
555		[ "$quiet" != "y" ] && zfs_log_failure_msg "${ZFS_ERROR}"
556
557		disable_plymouth
558		echo ""
559		echo "Command: $ZFS_CMD"
560		echo "Message: $ZFS_STDERR"
561		echo "Error: $ZFS_ERROR"
562		echo ""
563		echo "Failed to rollback snapshot."
564		shell
565	else
566		[ "$quiet" != "y" ] && zfs_log_end_msg
567	fi
568
569	return 0
570}
571
572# Get a list of snapshots, give them as a numbered list
573# to the user to choose from.
574ask_user_snap()
575{
576	fs="$1"
577
578	# We need to temporarily disable debugging. Set 'debug' so we
579	# remember to enabled it again.
580	if [ -n "${ZFS_DEBUG}" ]; then
581		unset ZFS_DEBUG
582		set +x
583		debug=1
584	fi
585
586	# Because we need the resulting snapshot, which is sent on
587	# stdout to the caller, we use stderr for our questions.
588	echo "What snapshot do you want to boot from?" > /dev/stderr
589	# shellcheck disable=SC2046
590	IFS="
591" set -- $("${ZFS}" list -H -oname -tsnapshot -r "${fs}")
592
593	i=1
594	for snap in "$@"; do
595		echo "  $i: $snap"
596		i=$((i + 1))
597	done > /dev/stderr
598
599	# expr instead of test here because [ a -lt 0 ] errors out,
600	# but expr falls back to lexicographical, which works out right
601	snapnr=0
602	while expr "$snapnr" "<" 1 > /dev/null ||
603	    expr "$snapnr" ">" "$#" > /dev/null
604	do
605		printf "%s" "Snap nr [1-$#]? " > /dev/stderr
606		read -r snapnr
607	done
608
609	# Re-enable debugging.
610	if [ -n "${debug}" ]; then
611		ZFS_DEBUG=1
612		set -x
613	fi
614
615	eval echo '$'"$snapnr"
616}
617
618setup_snapshot_booting()
619{
620	snap="$1"
621	retval=0
622
623	# Make sure that the snapshot specified actually exists.
624	if [ -z "$(get_fs_value "${snap}" type)" ]
625	then
626		# Snapshot does not exist (...@<null> ?)
627		# ask the user for a snapshot to use.
628		snap="$(ask_user_snap "${snap%%@*}")"
629	fi
630
631	# Separate the full snapshot ('$snap') into it's filesystem and
632	# snapshot names. Would have been nice with a split() function..
633	rootfs="${snap%%@*}"
634	snapname="${snap##*@}"
635	ZFS_BOOTFS="${rootfs}_${snapname}"
636
637	if ! grep -qiE '(^|[^\\](\\\\)* )(rollback)=(on|yes|1)( |$)' /proc/cmdline
638	then
639		# If the destination dataset for the clone
640		# already exists, destroy it. Recursively
641		if [ -n "$(get_fs_value "${rootfs}_${snapname}" type)" ]
642		then
643			filesystems=$("${ZFS}" list -oname -tfilesystem -H \
644			    -r -Sname "${ZFS_BOOTFS}")
645			for fs in $filesystems; do
646				destroy_fs "${fs}"
647			done
648		fi
649	fi
650
651	# Get all snapshots, recursively (might need to clone /usr, /var etc
652	# as well).
653	for s in $("${ZFS}" list -H -oname -tsnapshot -r "${rootfs}" | \
654	    grep "${snapname}")
655	do
656		if grep -qiE '(^|[^\\](\\\\)* )(rollback)=(on|yes|1)( |$)' /proc/cmdline
657		then
658			# Rollback snapshot
659			rollback_snap "$s" || retval=$((retval + 1))
660			ZFS_BOOTFS="${rootfs}"
661		else
662			# Setup a destination filesystem name.
663			# Ex: Called with 'rpool/ROOT/debian@snap2'
664			#       rpool/ROOT/debian@snap2		=> rpool/ROOT/debian_snap2
665			#       rpool/ROOT/debian/boot@snap2	=> rpool/ROOT/debian_snap2/boot
666			#       rpool/ROOT/debian/usr@snap2	=> rpool/ROOT/debian_snap2/usr
667			#       rpool/ROOT/debian/var@snap2	=> rpool/ROOT/debian_snap2/var
668			subfs="${s##"$rootfs"}"
669			subfs="${subfs%%@"$snapname"}"
670
671			destfs="${rootfs}_${snapname}" # base fs.
672			[ -n "$subfs" ] && destfs="${destfs}$subfs" # + sub fs.
673
674			# Get the mountpoint of the filesystem, to be used
675			# with clone_snap(). If legacy or none, then use
676			# the sub fs value.
677			mountpoint=$(get_fs_value "${s%%@*}" mountpoint)
678			if [ "$mountpoint" = "legacy" ] || \
679			   [ "$mountpoint" = "none" ]
680			then
681				if [ -n "${subfs}" ]; then
682					mountpoint="${subfs}"
683				else
684					mountpoint="/"
685				fi
686			fi
687
688			# Clone the snapshot into its own
689			# filesystem
690			clone_snap "$s" "${destfs}" "${mountpoint}" || \
691			    retval=$((retval + 1))
692		fi
693	done
694
695	# If we haven't return yet, we have a problem...
696	return "${retval}"
697}
698
699# ================================================================
700
701# This is the main function.
702mountroot()
703{
704	# ----------------------------------------------------------------
705	# I N I T I A L   S E T U P
706
707	# ------------
708	# Run the pre-mount scripts from /scripts/local-top.
709	pre_mountroot
710
711	# ------------
712	# Source the default setup variables.
713	[ -r '/etc/default/zfs' ] && . /etc/default/zfs
714
715	# ------------
716	# Support debug option
717	if grep -qiE '(^|[^\\](\\\\)* )(zfs_debug|zfs\.debug|zfsdebug)=(on|yes|1)( |$)' /proc/cmdline
718	then
719		ZFS_DEBUG=1
720		mkdir /var/log
721		#exec 2> /var/log/boot.debug
722		set -x
723	fi
724
725	# ------------
726	# Load ZFS module etc.
727	if ! load_module_initrd; then
728		disable_plymouth
729		echo ""
730		echo "Failed to load ZFS modules."
731		echo "Manually load the modules and exit."
732		shell
733	fi
734
735	# ------------
736	# Look for the cache file (if any).
737	[ -f "${ZPOOL_CACHE}" ] || unset ZPOOL_CACHE
738	[ -s "${ZPOOL_CACHE}" ] || unset ZPOOL_CACHE
739
740	# ------------
741	# Compatibility: 'ROOT' is for Debian GNU/Linux (etc),
742	#		 'root' is for Redhat/Fedora (etc),
743	#		 'REAL_ROOT' is for Gentoo
744	if [ -z "$ROOT" ]
745	then
746		[ -n "$root" ] && ROOT=${root}
747
748		[ -n "$REAL_ROOT" ] && ROOT=${REAL_ROOT}
749	fi
750
751	# ------------
752	# Where to mount the root fs in the initrd - set outside this script
753	# Compatibility: 'rootmnt' is for Debian GNU/Linux (etc),
754	#		 'NEWROOT' is for RedHat/Fedora (etc),
755	#		 'NEW_ROOT' is for Gentoo
756	if [ -z "$rootmnt" ]
757	then
758		[ -n "$NEWROOT" ] && rootmnt=${NEWROOT}
759
760		[ -n "$NEW_ROOT" ] && rootmnt=${NEW_ROOT}
761	fi
762
763	# ------------
764	# No longer set in the defaults file, but it could have been set in
765	# get_pools() in some circumstances. If it's something, but not 'yes',
766	# it's no good to us.
767	[ -n "$USE_DISK_BY_ID" ] && [ "$USE_DISK_BY_ID" != 'yes' ] && \
768	    unset USE_DISK_BY_ID
769
770	# ----------------------------------------------------------------
771	# P A R S E   C O M M A N D   L I N E   O P T I O N S
772
773	# This part is the really ugly part - there's so many options and permutations
774	# 'out there', and if we should make this the 'primary' source for ZFS initrd
775	# scripting, we need/should support them all.
776	#
777	# Supports the following kernel command line argument combinations
778	# (in this order - first match win):
779	#
780	#	rpool=<pool>			(tries to finds bootfs automatically)
781	#	bootfs=<pool>/<dataset>		(uses this for rpool - first part)
782	#	rpool=<pool> bootfs=<pool>/<dataset>
783	#	-B zfs-bootfs=<pool>/<fs>	(uses this for rpool - first part)
784	#	rpool=rpool			(default if none of the above is used)
785	#	root=<pool>/<dataset>		(uses this for rpool - first part)
786	#	root=ZFS=<pool>/<dataset>	(uses this for rpool - first part, without 'ZFS=')
787	#	root=zfs:AUTO			(tries to detect both pool and rootfs)
788	#	root=zfs:<pool>/<dataset>	(uses this for rpool - first part, without 'zfs:')
789	#
790	# Option <dataset> could also be <snapshot>
791	# Option <pool> could also be <guid>
792
793	# ------------
794	# Support force option
795	# In addition, setting one of zfs_force, zfs.force or zfsforce to
796	# 'yes', 'on' or '1' will make sure we force import the pool.
797	# This should (almost) never be needed, but it's here for
798	# completeness.
799	ZPOOL_FORCE=""
800	if grep -qiE '(^|[^\\](\\\\)* )(zfs_force|zfs\.force|zfsforce)=(on|yes|1)( |$)' /proc/cmdline
801	then
802		ZPOOL_FORCE="-f"
803	fi
804
805	# ------------
806	# Look for 'rpool' and 'bootfs' parameter
807	[ -n "$rpool" ] && ZFS_RPOOL="${rpool#rpool=}"
808	[ -n "$bootfs" ] && ZFS_BOOTFS="${bootfs#bootfs=}"
809
810	# ------------
811	# If we have 'ROOT' (see above), but not 'ZFS_BOOTFS', then use
812	# 'ROOT'
813	[ -n "$ROOT" ] && [ -z "${ZFS_BOOTFS}" ] && ZFS_BOOTFS="$ROOT"
814
815	# ------------
816	# Check for the `-B zfs-bootfs=%s/%u,...` kind of parameter.
817	# NOTE: Only use the pool name and dataset. The rest is not
818	#       supported by OpenZFS (whatever it's for).
819	if [ -z "$ZFS_RPOOL" ]
820	then
821		# The ${zfs-bootfs} variable is set at the kernel command
822		# line, usually by GRUB, but it cannot be referenced here
823		# directly because bourne variable names cannot contain a
824		# hyphen.
825		#
826		# Reassign the variable by dumping the environment and
827		# stripping the zfs-bootfs= prefix.  Let the shell handle
828		# quoting through the eval command:
829		# shellcheck disable=SC2046
830		eval ZFS_RPOOL=$(set | sed -n -e 's,^zfs-bootfs=,,p')
831	fi
832
833	# ------------
834	# No root fs or pool specified - do auto detect.
835	if [ -z "$ZFS_RPOOL" ] && [ -z "${ZFS_BOOTFS}" ]
836	then
837		# Do auto detect. Do this by 'cheating' - set 'root=zfs:AUTO'
838		# which will be caught later
839		ROOT='zfs:AUTO'
840	fi
841
842	# ----------------------------------------------------------------
843	# F I N D   A N D   I M P O R T   C O R R E C T   P O O L
844
845	# ------------
846	if [ "$ROOT" = "zfs:AUTO" ]
847	then
848		# Try to detect both pool and root fs.
849
850		# If we got here, that means we don't have a hint so as to
851		# the root dataset, but with root=zfs:AUTO on cmdline,
852		# this says "zfs:AUTO" here and interferes with checks later
853		ZFS_BOOTFS=
854
855		[ "$quiet" != "y" ] && \
856		    zfs_log_begin_msg "Attempting to import additional pools."
857
858		# Get a list of pools available for import
859		if [ -n "$ZFS_RPOOL" ]
860		then
861			# We've specified a pool - check only that
862			POOLS=$ZFS_RPOOL
863		else
864			POOLS=$(get_pools)
865		fi
866
867		OLD_IFS="$IFS" ; IFS=";"
868		for pool in $POOLS
869		do
870			[ -z "$pool" ] && continue
871
872			IFS="$OLD_IFS" import_pool "$pool"
873			IFS="$OLD_IFS" find_rootfs "$pool" && break
874		done
875		IFS="$OLD_IFS"
876
877		[ "$quiet" != "y" ] && zfs_log_end_msg "$ZFS_ERROR"
878	else
879		# No auto - use value from the command line option.
880
881		# Strip 'zfs:' and 'ZFS='.
882		ZFS_BOOTFS="${ROOT#*[:=]}"
883
884		# Strip everything after the first slash.
885		ZFS_RPOOL="${ZFS_BOOTFS%%/*}"
886	fi
887
888	# Import the pool (if not already done so in the AUTO check above).
889	if [ -n "$ZFS_RPOOL" ] && [ -z "${POOL_IMPORTED}" ]
890	then
891		[ "$quiet" != "y" ] && \
892		    zfs_log_begin_msg "Importing ZFS root pool '$ZFS_RPOOL'"
893
894		import_pool "${ZFS_RPOOL}"
895		find_rootfs "${ZFS_RPOOL}"
896
897		[ "$quiet" != "y" ] && zfs_log_end_msg
898	fi
899
900	if [ -z "${POOL_IMPORTED}" ]
901	then
902		# No pool imported, this is serious!
903		disable_plymouth
904		echo ""
905		echo "Command: $ZFS_CMD"
906		echo "Message: $ZFS_STDERR"
907		echo "Error: $ZFS_ERROR"
908		echo ""
909		echo "No pool imported. Manually import the root pool"
910		echo "at the command prompt and then exit."
911		echo "Hint: Try:  zpool import -N ${ZFS_RPOOL}"
912		shell
913	fi
914
915	# In case the pool was specified as guid, resolve guid to name
916	pool="$("${ZPOOL}" get -H -o name,value name,guid | \
917	    awk -v pool="${ZFS_RPOOL}" '$2 == pool { print $1 }')"
918	if [ -n "$pool" ]; then
919		# If $ZFS_BOOTFS contains guid, replace the guid portion with $pool
920		ZFS_BOOTFS=$(echo "$ZFS_BOOTFS" | \
921			sed -e "s/$("${ZPOOL}" get -H -o value guid "$pool")/$pool/g")
922		ZFS_RPOOL="${pool}"
923	fi
924
925
926	# ----------------------------------------------------------------
927	# P R E P A R E   R O O T   F I L E S Y S T E M
928
929	if [ -n "${ZFS_BOOTFS}" ]
930	then
931		# Booting from a snapshot?
932		# Will overwrite the ZFS_BOOTFS variable like so:
933		#   rpool/ROOT/debian@snap2 => rpool/ROOT/debian_snap2
934		echo "${ZFS_BOOTFS}" | grep -q '@' && \
935		    setup_snapshot_booting "${ZFS_BOOTFS}"
936	fi
937
938	if [ -z "${ZFS_BOOTFS}" ]
939	then
940		# Still nothing! Let the user sort this out.
941		disable_plymouth
942		echo ""
943		echo "Error: Unknown root filesystem - no 'bootfs' pool property and"
944		echo "       not specified on the kernel command line."
945		echo ""
946		echo "Manually mount the root filesystem on $rootmnt and then exit."
947		echo "Hint: Try:  mount -o zfsutil -t zfs ${ZFS_RPOOL-rpool}/ROOT/system $rootmnt"
948		shell
949	fi
950
951	# ----------------------------------------------------------------
952	# M O U N T   F I L E S Y S T E M S
953
954	# * Ideally, the root filesystem would be mounted like this:
955	#
956	#     zpool import -R "$rootmnt" -N "$ZFS_RPOOL"
957	#     zfs mount -o mountpoint=/ "${ZFS_BOOTFS}"
958	#
959	#   but the MOUNTPOINT prefix is preserved on descendent filesystem
960	#   after the pivot into the regular root, which later breaks things
961	#   like `zfs mount -a` and the /proc/self/mounts refresh.
962	#
963	# * Mount additional filesystems required
964	#   Such as /usr, /var, /usr/local etc.
965	#   NOTE: Mounted in the order specified in the
966	#         ZFS_INITRD_ADDITIONAL_DATASETS variable so take care!
967
968	# Go through the complete list (recursively) of all filesystems below
969	# the real root dataset
970	filesystems="$("${ZFS}" list -oname -tfilesystem -H -r "${ZFS_BOOTFS}")"
971	OLD_IFS="$IFS" ; IFS="
972"
973	for fs in $filesystems; do
974		IFS="$OLD_IFS" mount_fs "$fs"
975	done
976	IFS="$OLD_IFS"
977	for fs in $ZFS_INITRD_ADDITIONAL_DATASETS; do
978		mount_fs "$fs"
979	done
980
981	touch /run/zfs_unlock_complete
982	if [ -e /run/zfs_unlock_complete_notify ]; then
983		read -r < /run/zfs_unlock_complete_notify
984	fi
985
986	# ------------
987	# Debugging information
988	if [ -n "${ZFS_DEBUG}" ]
989	then
990		#exec 2>&1-
991
992		echo "DEBUG: imported pools:"
993		"${ZPOOL}" list -H
994		echo
995
996		echo "DEBUG: mounted ZFS filesystems:"
997		mount | grep zfs
998		echo
999
1000		echo "=> waiting for ENTER before continuing because of 'zfsdebug=1'. "
1001		printf "%s" "   'c' for shell, 'r' for reboot, 'ENTER' to continue. "
1002		read -r b
1003
1004		[ "$b" = "c" ] && /bin/sh
1005		[ "$b" = "r" ] && reboot -f
1006
1007		set +x
1008	fi
1009
1010	# ------------
1011	# Run local bottom script
1012	if command -v run_scripts > /dev/null 2>&1
1013	then
1014		if [ -f "/scripts/local-bottom" ] || [ -d "/scripts/local-bottom" ]
1015		then
1016			[ "$quiet" != "y" ] && \
1017			    zfs_log_begin_msg "Running /scripts/local-bottom"
1018			run_scripts /scripts/local-bottom
1019			[ "$quiet" != "y" ] && zfs_log_end_msg
1020		fi
1021	fi
1022}
1023