xref: /freebsd/sys/contrib/openzfs/udev/vdev_id (revision 924226fba12cc9a228c73b956e1b7fa24c60b055)
1#!/bin/sh
2#
3# vdev_id: udev helper to generate user-friendly names for JBOD disks
4#
5# This script parses the file /etc/zfs/vdev_id.conf to map a
6# physical path in a storage topology to a channel name.  The
7# channel name is combined with a disk enclosure slot number to
8# create an alias that reflects the physical location of the drive.
9# This is particularly helpful when it comes to tasks like replacing
10# failed drives.  Slot numbers may also be re-mapped in case the
11# default numbering is unsatisfactory.  The drive aliases will be
12# created as symbolic links in /dev/disk/by-vdev.
13#
14# The currently supported topologies are sas_direct and sas_switch.
15# A multipath mode is supported in which dm-mpath devices are
16# handled by examining the first-listed running component disk.  In
17# multipath mode the configuration file should contain a channel
18# definition with the same name for each path to a given enclosure.
19#
20# The alias keyword provides a simple way to map already-existing
21# device symlinks to more convenient names.  It is suitable for
22# small, static configurations or for sites that have some automated
23# way to generate the mapping file.
24#
25#
26# Some example configuration files are given below.
27
28# #
29# # Example vdev_id.conf - sas_direct.
30# #
31#
32# multipath     no
33# topology      sas_direct
34# phys_per_port 4
35# slot          bay
36#
37# #       PCI_ID  HBA PORT  CHANNEL NAME
38# channel 85:00.0 1         A
39# channel 85:00.0 0         B
40# channel 86:00.0 1         C
41# channel 86:00.0 0         D
42#
43# # Custom mapping for Channel A
44#
45# #    Linux      Mapped
46# #    Slot       Slot      Channel
47# slot 1          7         A
48# slot 2          10        A
49# slot 3          3         A
50# slot 4          6         A
51#
52# # Default mapping for B, C, and D
53# slot 1          4
54# slot 2          2
55# slot 3          1
56# slot 4          3
57
58# #
59# # Example vdev_id.conf - sas_switch
60# #
61#
62# topology      sas_switch
63#
64# #       SWITCH PORT  CHANNEL NAME
65# channel 1            A
66# channel 2            B
67# channel 3            C
68# channel 4            D
69
70# #
71# # Example vdev_id.conf - multipath
72# #
73#
74# multipath yes
75#
76# #       PCI_ID  HBA PORT  CHANNEL NAME
77# channel 85:00.0 1         A
78# channel 85:00.0 0         B
79# channel 86:00.0 1         A
80# channel 86:00.0 0         B
81
82# #
83# # Example vdev_id.conf - multipath / multijbod-daisychaining
84# #
85#
86# multipath yes
87# multijbod yes
88#
89# #       PCI_ID  HBA PORT  CHANNEL NAME
90# channel 85:00.0 1         A
91# channel 85:00.0 0         B
92# channel 86:00.0 1         A
93# channel 86:00.0 0         B
94
95# #
96# # Example vdev_id.conf - multipath / mixed
97# #
98#
99# multipath yes
100# slot mix
101#
102# #       PCI_ID  HBA PORT  CHANNEL NAME
103# channel 85:00.0 3         A
104# channel 85:00.0 2         B
105# channel 86:00.0 3         A
106# channel 86:00.0 2         B
107# channel af:00.0 0         C
108# channel af:00.0 1         C
109
110# #
111# # Example vdev_id.conf - alias
112# #
113#
114# #     by-vdev
115# #     name     fully qualified or base name of device link
116# alias d1       /dev/disk/by-id/wwn-0x5000c5002de3b9ca
117# alias d2       wwn-0x5000c5002def789e
118
119PATH=/bin:/sbin:/usr/bin:/usr/sbin
120CONFIG=/etc/zfs/vdev_id.conf
121PHYS_PER_PORT=
122DEV=
123TOPOLOGY=
124BAY=
125ENCL_ID=""
126UNIQ_ENCL_ID=""
127
128usage() {
129	cat << EOF
130Usage: vdev_id [-h]
131       vdev_id <-d device> [-c config_file] [-p phys_per_port]
132               [-g sas_direct|sas_switch|scsi] [-m]
133
134  -c    specify name of an alternative config file [default=$CONFIG]
135  -d    specify basename of device (i.e. sda)
136  -e    Create enclose device symlinks only (/dev/by-enclosure)
137  -g    Storage network topology [default="$TOPOLOGY"]
138  -m    Run in multipath mode
139  -j    Run in multijbod mode
140  -p    number of phy's per switch port [default=$PHYS_PER_PORT]
141  -h    show this summary
142EOF
143	exit 1
144	# exit with error to avoid processing usage message by a udev rule
145}
146
147map_slot() {
148	LINUX_SLOT=$1
149	CHANNEL=$2
150
151	MAPPED_SLOT=$(awk -v linux_slot="$LINUX_SLOT" -v channel="$CHANNEL" \
152			'$1 == "slot" && $2 == linux_slot && \
153			($4 ~ "^"channel"$" || $4 ~ /^$/) { print $3; exit}' $CONFIG)
154	if [ -z "$MAPPED_SLOT" ] ; then
155		MAPPED_SLOT=$LINUX_SLOT
156	fi
157	printf "%d" "${MAPPED_SLOT}"
158}
159
160map_channel() {
161	MAPPED_CHAN=
162	PCI_ID=$1
163	PORT=$2
164
165	case $TOPOLOGY in
166		"sas_switch")
167		MAPPED_CHAN=$(awk -v port="$PORT" \
168			'$1 == "channel" && $2 == port \
169			{ print $3; exit }' $CONFIG)
170		;;
171		"sas_direct"|"scsi")
172		MAPPED_CHAN=$(awk -v pciID="$PCI_ID" -v port="$PORT" \
173			'$1 == "channel" && $2 == pciID && $3 == port \
174			{print $4}' $CONFIG)
175		;;
176	esac
177	printf "%s" "${MAPPED_CHAN}"
178}
179
180get_encl_id() {
181	set -- $(echo $1)
182	count=$#
183
184	i=1
185	while [ $i -le $count ] ; do
186		d=$(eval echo '$'{$i})
187		id=$(cat "/sys/class/enclosure/${d}/id")
188		ENCL_ID="${ENCL_ID} $id"
189		i=$((i + 1))
190	done
191}
192
193get_uniq_encl_id() {
194	for uuid in ${ENCL_ID}; do
195		found=0
196
197		for count in ${UNIQ_ENCL_ID}; do
198			if [ $count = $uuid ]; then
199				found=1
200				break
201			fi
202		done
203
204		if [ $found -eq 0 ]; then
205			UNIQ_ENCL_ID="${UNIQ_ENCL_ID} $uuid"
206		fi
207	done
208}
209
210# map_jbod explainer: The bsg driver knows the difference between a SAS
211# expander and fanout expander. Use hostX instance along with top-level
212# (whole enclosure) expander instances in /sys/class/enclosure and
213# matching a field in an array of expanders, using the index of the
214# matched array field as the enclosure instance, thereby making jbod IDs
215# dynamic. Avoids reliance on high overhead userspace commands like
216# multipath and lsscsi and instead uses existing sysfs data.  $HOSTCHAN
217# variable derived from devpath gymnastics in sas_handler() function.
218map_jbod() {
219	DEVEXP=$(ls -l "/sys/block/$DEV/device/" | grep enclos | awk -F/ '{print $(NF-1) }')
220	DEV=$1
221
222	# Use "set --" to create index values (Arrays)
223	set -- $(ls -l /sys/class/enclosure | grep -v "^total" | awk '{print $9}')
224	# Get count of total elements
225	JBOD_COUNT=$#
226	JBOD_ITEM=$*
227
228	# Build JBODs (enclosure)  id from sys/class/enclosure/<dev>/id
229	get_encl_id "$JBOD_ITEM"
230	# Different expander instances for each paths.
231	# Filter out and keep only unique id.
232	get_uniq_encl_id
233
234	# Identify final 'mapped jbod'
235	j=0
236	for count in ${UNIQ_ENCL_ID}; do
237		i=1
238		j=$((j + 1))
239		while [ $i -le $JBOD_COUNT ] ; do
240			d=$(eval echo '$'{$i})
241			id=$(cat "/sys/class/enclosure/${d}/id")
242			if [ "$d" = "$DEVEXP" ] && [ $id = $count ] ; then
243				MAPPED_JBOD=$j
244				break
245			fi
246			i=$((i + 1))
247		done
248	done
249
250	printf "%d" "${MAPPED_JBOD}"
251}
252
253sas_handler() {
254	if [ -z "$PHYS_PER_PORT" ] ; then
255		PHYS_PER_PORT=$(awk '$1 == "phys_per_port" \
256			{print $2; exit}' $CONFIG)
257	fi
258	PHYS_PER_PORT=${PHYS_PER_PORT:-4}
259
260	if ! echo "$PHYS_PER_PORT" | grep -q -E '^[0-9]+$' ; then
261		echo "Error: phys_per_port value $PHYS_PER_PORT is non-numeric"
262		exit 1
263	fi
264
265	if [ -z "$MULTIPATH_MODE" ] ; then
266		MULTIPATH_MODE=$(awk '$1 == "multipath" \
267			{print $2; exit}' $CONFIG)
268	fi
269
270	if [ -z "$MULTIJBOD_MODE" ] ; then
271		MULTIJBOD_MODE=$(awk '$1 == "multijbod" \
272			{print $2; exit}' $CONFIG)
273	fi
274
275	# Use first running component device if we're handling a dm-mpath device
276	if [ "$MULTIPATH_MODE" = "yes" ] ; then
277		# If udev didn't tell us the UUID via DM_NAME, check /dev/mapper
278		if [ -z "$DM_NAME" ] ; then
279			DM_NAME=$(ls -l --full-time /dev/mapper |
280				grep "$DEV"$ | awk '{print $9}')
281		fi
282
283		# For raw disks udev exports DEVTYPE=partition when
284		# handling partitions, and the rules can be written to
285		# take advantage of this to append a -part suffix.  For
286		# dm devices we get DEVTYPE=disk even for partitions so
287		# we have to append the -part suffix directly in the
288		# helper.
289		if [ "$DEVTYPE" != "partition" ] ; then
290			# Match p[number], remove the 'p' and prepend "-part"
291			PART=$(echo "$DM_NAME" |
292				awk 'match($0,/p[0-9]+$/) {print "-part"substr($0,RSTART+1,RLENGTH-1)}')
293		fi
294
295		# Strip off partition information.
296		DM_NAME=$(echo "$DM_NAME" | sed 's/p[0-9][0-9]*$//')
297		if [ -z "$DM_NAME" ] ; then
298			return
299		fi
300
301		# Utilize DM device name to gather subordinate block devices
302		# using sysfs to avoid userspace utilities
303
304		# If our DEVNAME is something like /dev/dm-177, then we may be
305		# able to get our DMDEV from it.
306		DMDEV=$(echo $DEVNAME | sed 's;/dev/;;g')
307		if [ ! -e /sys/block/$DMDEV/slaves/* ] ; then
308			# It's not there, try looking in /dev/mapper
309			DMDEV=$(ls -l --full-time /dev/mapper | grep $DM_NAME |
310			awk '{gsub("../", " "); print $NF}')
311		fi
312
313		# Use sysfs pointers in /sys/block/dm-X/slaves because using
314		# userspace tools creates lots of overhead and should be avoided
315		# whenever possible. Use awk to isolate lowest instance of
316		# sd device member in dm device group regardless of string
317		# length.
318		DEV=$(ls "/sys/block/$DMDEV/slaves" | awk '
319			{ len=sprintf ("%20s",length($0)); gsub(/ /,0,str); a[NR]=len "_" $0; }
320			END {
321				asort(a)
322				print substr(a[1],22)
323			}')
324
325		if [ -z "$DEV" ] ; then
326			return
327		fi
328	fi
329
330	if echo "$DEV" | grep -q ^/devices/ ; then
331		sys_path=$DEV
332	else
333		sys_path=$(udevadm info -q path -p "/sys/block/$DEV" 2>/dev/null)
334	fi
335
336	# Use positional parameters as an ad-hoc array
337	set -- $(echo "$sys_path" | tr / ' ')
338	num_dirs=$#
339	scsi_host_dir="/sys"
340
341	# Get path up to /sys/.../hostX
342	i=1
343
344	while [ $i -le "$num_dirs" ] ; do
345		d=$(eval echo '$'{$i})
346		scsi_host_dir="$scsi_host_dir/$d"
347		echo "$d" | grep -q -E '^host[0-9]+$' && break
348		i=$((i + 1))
349	done
350
351	# Lets grab the SAS host channel number and save it for JBOD sorting later
352	HOSTCHAN=$(echo "$d" | awk -F/ '{ gsub("host","",$NF); print $NF}')
353
354	if [ $i = "$num_dirs" ] ; then
355		return
356	fi
357
358	PCI_ID=$(eval echo '$'{$((i -1))} | awk -F: '{print $2":"$3}')
359
360	# In sas_switch mode, the directory four levels beneath
361	# /sys/.../hostX contains symlinks to phy devices that reveal
362	# the switch port number.  In sas_direct mode, the phy links one
363	# directory down reveal the HBA port.
364	port_dir=$scsi_host_dir
365
366	case $TOPOLOGY in
367		"sas_switch") j=$((i + 4)) ;;
368		"sas_direct") j=$((i + 1)) ;;
369	esac
370
371	i=$((i + 1))
372
373	while [ $i -le $j ] ; do
374		port_dir="$port_dir/$(eval echo '$'{$i})"
375		i=$((i + 1))
376	done
377
378	PHY=$(ls -vd "$port_dir"/phy* 2>/dev/null | head -1 | awk -F: '{print $NF}')
379	if [ -z "$PHY" ] ; then
380		PHY=0
381	fi
382	PORT=$((PHY / PHYS_PER_PORT))
383
384	# Look in /sys/.../sas_device/end_device-X for the bay_identifier
385	# attribute.
386	end_device_dir=$port_dir
387
388	while [ $i -lt "$num_dirs" ] ; do
389		d=$(eval echo '$'{$i})
390		end_device_dir="$end_device_dir/$d"
391		if echo "$d" | grep -q '^end_device' ; then
392			end_device_dir="$end_device_dir/sas_device/$d"
393			break
394		fi
395		i=$((i + 1))
396	done
397
398	# Add 'mix' slot type for environments where dm-multipath devices
399	# include end-devices connected via SAS expanders or direct connection
400	# to SAS HBA. A mixed connectivity environment such as pool devices
401	# contained in a SAS JBOD and spare drives or log devices directly
402	# connected in a server backplane without expanders in the I/O path.
403	SLOT=
404
405	case $BAY in
406	"bay")
407		SLOT=$(cat "$end_device_dir/bay_identifier" 2>/dev/null)
408		;;
409	"mix")
410		if [ $(cat "$end_device_dir/bay_identifier" 2>/dev/null) ] ; then
411			SLOT=$(cat "$end_device_dir/bay_identifier" 2>/dev/null)
412		else
413			SLOT=$(cat "$end_device_dir/phy_identifier" 2>/dev/null)
414		fi
415		;;
416	"phy")
417		SLOT=$(cat "$end_device_dir/phy_identifier" 2>/dev/null)
418		;;
419	"port")
420		d=$(eval echo '$'{$i})
421		SLOT=$(echo "$d" | sed -e 's/^.*://')
422		;;
423	"id")
424		i=$((i + 1))
425		d=$(eval echo '$'{$i})
426		SLOT=$(echo "$d" | sed -e 's/^.*://')
427		;;
428	"lun")
429		i=$((i + 2))
430		d=$(eval echo '$'{$i})
431		SLOT=$(echo "$d" | sed -e 's/^.*://')
432		;;
433	"ses")
434		# look for this SAS path in all SCSI Enclosure Services
435		# (SES) enclosures
436		sas_address=$(cat "$end_device_dir/sas_address" 2>/dev/null)
437		enclosures=$(lsscsi -g | \
438			sed -n -e '/enclosu/s/^.* \([^ ][^ ]*\) *$/\1/p')
439		for enclosure in $enclosures; do
440			set -- $(sg_ses -p aes "$enclosure" | \
441				awk "/device slot number:/{slot=\$12} \
442					/SAS address: $sas_address/\
443					{print slot}")
444			SLOT=$1
445			if [ -n "$SLOT" ] ; then
446				break
447			fi
448		done
449		;;
450	esac
451	if [ -z "$SLOT" ] ; then
452		return
453	fi
454
455	if [ "$MULTIJBOD_MODE" = "yes" ] ; then
456		CHAN=$(map_channel "$PCI_ID" "$PORT")
457		SLOT=$(map_slot "$SLOT" "$CHAN")
458		JBOD=$(map_jbod "$DEV")
459
460		if [ -z "$CHAN" ] ; then
461			return
462		fi
463		echo "${CHAN}"-"${JBOD}"-"${SLOT}${PART}"
464	else
465		CHAN=$(map_channel "$PCI_ID" "$PORT")
466		SLOT=$(map_slot "$SLOT" "$CHAN")
467
468		if [ -z "$CHAN" ] ; then
469			return
470		fi
471		echo "${CHAN}${SLOT}${PART}"
472	fi
473}
474
475scsi_handler() {
476	if [ -z "$FIRST_BAY_NUMBER" ] ; then
477		FIRST_BAY_NUMBER=$(awk '$1 == "first_bay_number" \
478			{print $2; exit}' $CONFIG)
479	fi
480	FIRST_BAY_NUMBER=${FIRST_BAY_NUMBER:-0}
481
482	if [ -z "$PHYS_PER_PORT" ] ; then
483		PHYS_PER_PORT=$(awk '$1 == "phys_per_port" \
484			{print $2; exit}' $CONFIG)
485	fi
486	PHYS_PER_PORT=${PHYS_PER_PORT:-4}
487
488	if ! echo "$PHYS_PER_PORT" | grep -q -E '^[0-9]+$' ; then
489		echo "Error: phys_per_port value $PHYS_PER_PORT is non-numeric"
490		exit 1
491	fi
492
493	if [ -z "$MULTIPATH_MODE" ] ; then
494		MULTIPATH_MODE=$(awk '$1 == "multipath" \
495			{print $2; exit}' $CONFIG)
496	fi
497
498	# Use first running component device if we're handling a dm-mpath device
499	if [ "$MULTIPATH_MODE" = "yes" ] ; then
500		# If udev didn't tell us the UUID via DM_NAME, check /dev/mapper
501		if [ -z "$DM_NAME" ] ; then
502			DM_NAME=$(ls -l --full-time /dev/mapper |
503				grep "$DEV"$ | awk '{print $9}')
504		fi
505
506		# For raw disks udev exports DEVTYPE=partition when
507		# handling partitions, and the rules can be written to
508		# take advantage of this to append a -part suffix.  For
509		# dm devices we get DEVTYPE=disk even for partitions so
510		# we have to append the -part suffix directly in the
511		# helper.
512		if [ "$DEVTYPE" != "partition" ] ; then
513			# Match p[number], remove the 'p' and prepend "-part"
514			PART=$(echo "$DM_NAME" |
515			    awk 'match($0,/p[0-9]+$/) {print "-part"substr($0,RSTART+1,RLENGTH-1)}')
516		fi
517
518		# Strip off partition information.
519		DM_NAME=$(echo "$DM_NAME" | sed 's/p[0-9][0-9]*$//')
520		if [ -z "$DM_NAME" ] ; then
521			return
522		fi
523
524		# Get the raw scsi device name from multipath -ll. Strip off
525		# leading pipe symbols to make field numbering consistent.
526		DEV=$(multipath -ll "$DM_NAME" |
527			awk '/running/{gsub("^[|]"," "); print $3 ; exit}')
528		if [ -z "$DEV" ] ; then
529			return
530		fi
531	fi
532
533	if echo "$DEV" | grep -q ^/devices/ ; then
534		sys_path=$DEV
535	else
536		sys_path=$(udevadm info -q path -p "/sys/block/$DEV" 2>/dev/null)
537	fi
538
539	# expect sys_path like this, for example:
540	# /devices/pci0000:00/0000:00:0b.0/0000:09:00.0/0000:0a:05.0/0000:0c:00.0/host3/target3:1:0/3:1:0:21/block/sdv
541
542	# Use positional parameters as an ad-hoc array
543	set -- $(echo "$sys_path" | tr / ' ')
544	num_dirs=$#
545	scsi_host_dir="/sys"
546
547	# Get path up to /sys/.../hostX
548	i=1
549
550	while [ $i -le "$num_dirs" ] ; do
551		d=$(eval echo '$'{$i})
552		scsi_host_dir="$scsi_host_dir/$d"
553
554		echo "$d" | grep -q -E '^host[0-9]+$' && break
555		i=$((i + 1))
556	done
557
558	if [ $i = "$num_dirs" ] ; then
559		return
560	fi
561
562	PCI_ID=$(eval echo '$'{$((i -1))} | awk -F: '{print $2":"$3}')
563
564	# In scsi mode, the directory two levels beneath
565	# /sys/.../hostX reveals the port and slot.
566	port_dir=$scsi_host_dir
567	j=$((i + 2))
568
569	i=$((i + 1))
570	while [ $i -le $j ] ; do
571		port_dir="$port_dir/$(eval echo '$'{$i})"
572		i=$((i + 1))
573	done
574
575	set -- $(echo "$port_dir" | sed -e 's/^.*:\([^:]*\):\([^:]*\)$/\1 \2/')
576	PORT=$1
577	SLOT=$(($2 + FIRST_BAY_NUMBER))
578
579	if [ -z "$SLOT" ] ; then
580		return
581	fi
582
583	CHAN=$(map_channel "$PCI_ID" "$PORT")
584	SLOT=$(map_slot "$SLOT" "$CHAN")
585
586	if [ -z "$CHAN" ] ; then
587		return
588	fi
589	echo "${CHAN}${SLOT}${PART}"
590}
591
592# Figure out the name for the enclosure symlink
593enclosure_handler () {
594	# We get all the info we need from udev's DEVPATH variable:
595	#
596	# DEVPATH=/sys/devices/pci0000:00/0000:00:03.0/0000:05:00.0/host0/subsystem/devices/0:0:0:0/scsi_generic/sg0
597
598	# Get the enclosure ID ("0:0:0:0")
599	ENC="${DEVPATH%/*}"
600	ENC="${ENC%/*}"
601	ENC="${ENC##*/}"
602	if [ ! -d "/sys/class/enclosure/$ENC" ] ; then
603		# Not an enclosure, bail out
604		return
605	fi
606
607	# Get the long sysfs device path to our enclosure. Looks like:
608	# /devices/pci0000:00/0000:00:03.0/0000:05:00.0/host0/port-0:0/ ... /enclosure/0:0:0:0
609
610	ENC_DEVICE=$(readlink "/sys/class/enclosure/$ENC")
611
612	# Grab the full path to the hosts port dir:
613	# /devices/pci0000:00/0000:00:03.0/0000:05:00.0/host0/port-0:0
614	PORT_DIR=$(echo "$ENC_DEVICE" | grep -Eo '.+host[0-9]+/port-[0-9]+:[0-9]+')
615
616	# Get the port number
617	PORT_ID=$(echo "$PORT_DIR" | grep -Eo "[0-9]+$")
618
619	# The PCI directory is two directories up from the port directory
620	# /sys/devices/pci0000:00/0000:00:03.0/0000:05:00.0
621	PCI_ID_LONG="$(readlink -m "/sys/$PORT_DIR/../..")"
622	PCI_ID_LONG="${PCI_ID_LONG##*/}"
623
624	# Strip down the PCI address from 0000:05:00.0 to 05:00.0
625	PCI_ID="${PCI_ID_LONG#[0-9]*:}"
626
627	# Name our device according to vdev_id.conf (like "L0" or "U1").
628	NAME=$(awk "/channel/{if (\$1 == \"channel\" && \$2 == \"$PCI_ID\" && \
629		\$3 == \"$PORT_ID\") {print \$4\$3}}" $CONFIG)
630
631	echo "${NAME}"
632}
633
634alias_handler () {
635	# Special handling is needed to correctly append a -part suffix
636	# to partitions of device mapper devices.  The DEVTYPE attribute
637	# is normally set to "disk" instead of "partition" in this case,
638	# so the udev rules won't handle that for us as they do for
639	# "plain" block devices.
640	#
641	# For example, we may have the following links for a device and its
642	# partitions,
643	#
644	#  /dev/disk/by-id/dm-name-isw_dibgbfcije_ARRAY0   -> ../../dm-0
645	#  /dev/disk/by-id/dm-name-isw_dibgbfcije_ARRAY0p1 -> ../../dm-1
646	#  /dev/disk/by-id/dm-name-isw_dibgbfcije_ARRAY0p2 -> ../../dm-3
647	#
648	# and the following alias in vdev_id.conf.
649	#
650	#   alias A0 dm-name-isw_dibgbfcije_ARRAY0
651	#
652	# The desired outcome is for the following links to be created
653	# without having explicitly defined aliases for the partitions.
654	#
655	#  /dev/disk/by-vdev/A0       -> ../../dm-0
656	#  /dev/disk/by-vdev/A0-part1 -> ../../dm-1
657	#  /dev/disk/by-vdev/A0-part2 -> ../../dm-3
658	#
659	# Warning: The following grep pattern will misidentify whole-disk
660	#          devices whose names end with 'p' followed by a string of
661	#          digits as partitions, causing alias creation to fail. This
662	#          ambiguity seems unavoidable, so devices using this facility
663	#          must not use such names.
664	DM_PART=
665	if echo "$DM_NAME" | grep -q -E 'p[0-9][0-9]*$' ; then
666		if [ "$DEVTYPE" != "partition" ] ; then
667			# Match p[number], remove the 'p' and prepend "-part"
668			DM_PART=$(echo "$DM_NAME" |
669			    awk 'match($0,/p[0-9]+$/) {print "-part"substr($0,RSTART+1,RLENGTH-1)}')
670		fi
671	fi
672
673	# DEVLINKS attribute must have been populated by already-run udev rules.
674	for link in $DEVLINKS ; do
675		# Remove partition information to match key of top-level device.
676		if [ -n "$DM_PART" ] ; then
677			link=$(echo "$link" | sed 's/p[0-9][0-9]*$//')
678		fi
679		# Check both the fully qualified and the base name of link.
680		for l in $link ${link##*/} ; do
681			if [ ! -z "$l" ]; then
682				alias=$(awk -v var="$l" '($1 == "alias") && \
683					($3 == var) \
684					{ print $2; exit }' $CONFIG)
685				if [ -n "$alias" ] ; then
686					echo "${alias}${DM_PART}"
687					return
688				fi
689			fi
690		done
691	done
692}
693
694# main
695while getopts 'c:d:eg:jmp:h' OPTION; do
696	case ${OPTION} in
697	c)
698		CONFIG=${OPTARG}
699		;;
700	d)
701		DEV=${OPTARG}
702		;;
703	e)
704	# When udev sees a scsi_generic device, it calls this script with -e to
705	# create the enclosure device symlinks only.  We also need
706	# "enclosure_symlinks yes" set in vdev_id.config to actually create the
707	# symlink.
708	ENCLOSURE_MODE=$(awk '{if ($1 == "enclosure_symlinks") \
709		print $2}' "$CONFIG")
710
711	if [ "$ENCLOSURE_MODE" != "yes" ] ; then
712		exit 0
713	fi
714		;;
715	g)
716		TOPOLOGY=$OPTARG
717		;;
718	p)
719		PHYS_PER_PORT=${OPTARG}
720		;;
721	j)
722		MULTIJBOD_MODE=yes
723		;;
724	m)
725		MULTIPATH_MODE=yes
726		;;
727	h)
728		usage
729		;;
730	esac
731done
732
733if [ ! -r "$CONFIG" ] ; then
734	echo "Error: Config file \"$CONFIG\" not found"
735	exit 1
736fi
737
738if [ -z "$DEV" ] && [ -z "$ENCLOSURE_MODE" ] ; then
739	echo "Error: missing required option -d"
740	exit 1
741fi
742
743if [ -z "$TOPOLOGY" ] ; then
744	TOPOLOGY=$(awk '($1 == "topology") {print $2; exit}' "$CONFIG")
745fi
746
747if [ -z "$BAY" ] ; then
748	BAY=$(awk '($1 == "slot") {print $2; exit}' "$CONFIG")
749fi
750
751TOPOLOGY=${TOPOLOGY:-sas_direct}
752
753# Should we create /dev/by-enclosure symlinks?
754if [ "$ENCLOSURE_MODE" = "yes" ] && [ "$TOPOLOGY" = "sas_direct" ] ; then
755	ID_ENCLOSURE=$(enclosure_handler)
756	if [ -z "$ID_ENCLOSURE" ] ; then
757		exit 0
758	fi
759
760	# Just create the symlinks to the enclosure devices and then exit.
761	ENCLOSURE_PREFIX=$(awk '/enclosure_symlinks_prefix/{print $2}' "$CONFIG")
762	if [ -z "$ENCLOSURE_PREFIX" ] ; then
763		ENCLOSURE_PREFIX="enc"
764	fi
765	echo "ID_ENCLOSURE=$ID_ENCLOSURE"
766	echo "ID_ENCLOSURE_PATH=by-enclosure/$ENCLOSURE_PREFIX-$ID_ENCLOSURE"
767	exit 0
768fi
769
770# First check if an alias was defined for this device.
771ID_VDEV=$(alias_handler)
772
773if [ -z "$ID_VDEV" ] ; then
774	BAY=${BAY:-bay}
775	case $TOPOLOGY in
776		sas_direct|sas_switch)
777			ID_VDEV=$(sas_handler)
778			;;
779		scsi)
780			ID_VDEV=$(scsi_handler)
781			;;
782		*)
783			echo "Error: unknown topology $TOPOLOGY"
784			exit 1
785			;;
786	esac
787fi
788
789if [ -n "$ID_VDEV" ] ; then
790	echo "ID_VDEV=${ID_VDEV}"
791	echo "ID_VDEV_PATH=disk/by-vdev/${ID_VDEV}"
792fi
793