udev/10-dm.rules.in - manifest_repos/lvm2 - Git at Google

 # Copyright (C) 2009 Red Hat, Inc. All rights reserved.
 #
 # This file is part of LVM2.

 # Udev rules for device-mapper devices.
 #
 # These rules create a DM control node in /dev/(DM_DIR) directory.
 # The rules also create nodes named dm-x (x is a number) in /dev
 # directory and symlinks to these nodes with names given by
 # the actual DM names. Some udev environment variables are set
 # for use in later rules:
 #   DM_NAME - actual DM device's name
 #   DM_UUID - UUID set for DM device (blank if not specified)
 #   DM_SUSPENDED - suspended state of DM device (0 or 1)
 #   DM_UDEV_RULES_VSN - DM udev rules version
 #
 # These rules cover only basic device-mapper functionality in udev.
 #
 # Various DM subsystems may contain further subsystem-specific rules
 # in 11-dm-<subsystem_name>.rules which should be installed together
 # with the DM subsystem and which extend these basic rules.
 # For example:
 #   11-dm-lvm.rules for LVM subsystem
 #   11-dm-mpath.rules for multipath subsystem (since version 0.6.0, recommended!)
 #
 # Even more specific rules may be required by subsystems so always
 # check subsystem's upstream repository for recent set of rules.
 # Also, keep in mind that recent rules may also require recent
 # subsystem-specific binaries.

 KERNEL=="device-mapper", NAME="(DM_DIR)/control"

 SUBSYSTEM!="block", GOTO="dm_end"
 KERNEL!="dm-[0-9]*", GOTO="dm_end"
 (DM_EXEC_RULE)

 # Device created, major and minor number assigned - "add" event generated.
 # Table loaded - no event generated.
 # Device resumed (or renamed) - "change" event generated.
 # Device removed - "remove" event generated.
 #
 # The dm-X nodes are always created, even on "add" event, we can't suppress
 # that (the node is created even earlier with devtmpfs). All the symlinks
 # (e.g. /dev/mapper) are created in right time after a device has its table
 # loaded and is properly resumed. For this reason, direct use of dm-X nodes
 # is not recommended.
 ACTION!="add|change", GOTO="dm_end"

 # Decode udev control flags and set environment variables appropriately.
 # These flags are encoded in DM_COOKIE variable that was introduced in
 # kernel version 2.6.31. Therefore, we can use this feature with
 # kernels >= 2.6.31 only. Cookie is not decoded for remove event.
 ENV{DM_COOKIE}=="?*", IMPORT{program}="(DM_EXEC)/dmsetup udevflags $env{DM_COOKIE}"

 # Rule out easy-to-detect inappropriate events first.
 ENV{DISK_RO}=="1", GOTO="dm_disable"

 # There is no cookie set nor any flags encoded in events not originating
 # in libdevmapper so we need to detect this and try to behave correctly.
 # For such spurious events, regenerate all flags from current udev database content
 # (this information would normally be inaccessible for spurious ADD and CHANGE events).
 ENV{DM_UDEV_PRIMARY_SOURCE_FLAG}=="1", ENV{DM_ACTIVATION}="1", GOTO="dm_flags_done"
 IMPORT{db}="DM_UDEV_DISABLE_DM_RULES_FLAG"
 IMPORT{db}="DM_UDEV_DISABLE_SUBSYSTEM_RULES_FLAG"
 IMPORT{db}="DM_UDEV_DISABLE_DISK_RULES_FLAG"
 IMPORT{db}="DM_UDEV_DISABLE_OTHER_RULES_FLAG"
 IMPORT{db}="DM_UDEV_LOW_PRIORITY_FLAG"
 IMPORT{db}="DM_UDEV_DISABLE_LIBRARY_FALLBACK_FLAG"
 IMPORT{db}="DM_UDEV_PRIMARY_SOURCE_FLAG"
 IMPORT{db}="DM_UDEV_FLAG7"
 IMPORT{db}="DM_UDEV_RULES_VSN"
 LABEL="dm_flags_done"

 # Normally, we operate on "change" events. But when coldplugging, there's an
 # "add" event present. We have to recognize this and do our actions in this
 # particular situation, too. Also, we don't want the nodes to be created
 # prematurely on "add" events while not coldplugging. We check
 # DM_UDEV_PRIMARY_SOURCE_FLAG to see if the device was activated correctly
 # before and if not, we ignore the "add" event totally. This way we can support
 # udev triggers generating "add" events (e.g. "udevadm trigger --action=add" or
 # "echo add > /sys/block/<dm_device>/uevent"). The trigger with "add" event is
 # also used at boot to reevaluate udev rules for all existing devices activated
 # before (e.g. in initrd). If udev is used in initrd, we require the udev init
 # script to not remove the existing udev database so we can reuse the information
 # stored at the time of device activation in the initrd.
 ACTION!="add", GOTO="dm_no_coldplug"
 ENV{DM_UDEV_RULES_VSN}!="1", ENV{DM_UDEV_PRIMARY_SOURCE_FLAG}!="1", GOTO="dm_disable"
 ENV{DM_ACTIVATION}="1"
 LABEL="dm_no_coldplug"

 # Putting it together, following table is used to recognize genuine and spurious events.
 # N.B. Spurious events are generated based on use of the WATCH udev
 # rule or by triggering an event manually by "udevadm trigger" call
 # or by "echo <event_name> > /sys/block/dm-X/uevent".
 #
 #        EVENT              DM_UDEV_PRIMARY_SOURCE_FLAG   DM_ACTIVATION
 # ======================================================================
 # add event (genuine)                  0                        0
 # change event (genuine)               1                        1
 # add event (spurious)
 #   |_ dev still not active            0                        0
 #   \_ dev already active              1                        1
 # change event (spurious)
 #   |_ dev still not active            0                        0
 #   \_ dev already active              1                        0

 # "dm" sysfs subdirectory is available in newer versions of DM
 # only (kernels >= 2.6.29). We have to check for its existence
 # and use dmsetup tool instead to get the DM name, uuid and
 # suspended state if the "dm" subdirectory is not present.
 # The "suspended" item was added even later (kernels >= 2.6.31),
 # so we also have to call dmsetup if the kernel version used
 # is in between these releases.
 TEST=="dm", ENV{DM_NAME}="$attr{dm/name}", ENV{DM_UUID}="$attr{dm/uuid}", ENV{DM_SUSPENDED}="$attr{dm/suspended}"
 TEST!="dm", IMPORT{program}="(DM_EXEC)/dmsetup info -j %M -m %m -c --nameprefixes --noheadings --rows -o name,uuid,suspended"
 ENV{DM_SUSPENDED}!="?*", IMPORT{program}="(DM_EXEC)/dmsetup info -j %M -m %m -c --nameprefixes --noheadings --rows -o suspended"

 # dmsetup tool provides suspended state information in textual
 # form with values "Suspended"/"Active". We translate it to
 # 0/1 respectively to be consistent with sysfs values.
 ENV{DM_SUSPENDED}=="Active", ENV{DM_SUSPENDED}="0"
 ENV{DM_SUSPENDED}=="Suspended", ENV{DM_SUSPENDED}="1"

 # This variable provides a reliable way to check that device-mapper
 # rules were installed. It means that all needed variables are set
 # by these rules directly so there's no need to acquire them again
 # later. Other rules can alternate the functionality based on this
 # fact (e.g. fallback to rules that behave correctly even without
 # these rules installed). It also provides versioning for any
 # possible future changes.
 # VSN 1 - original rules
 # VSN 2 - add support for synthesized events
 ENV{DM_UDEV_RULES_VSN}="2"

 ENV{DM_UDEV_DISABLE_DM_RULES_FLAG}!="1", ENV{DM_NAME}=="?*", SYMLINK+="(DM_DIR)/$env{DM_NAME}"

 # Avoid processing and scanning a DM device in the other (foreign)
 # rules if it is in suspended state. However, we still keep 'disk'
 # and 'DM subsystem' related rules enabled in this case.
 ENV{DM_SUSPENDED}=="1", ENV{DM_UDEV_DISABLE_OTHER_RULES_FLAG}="1"

 GOTO="dm_end"

 LABEL="dm_disable"
 ENV{DM_UDEV_DISABLE_SUBSYSTEM_RULES_FLAG}="1"
 ENV{DM_UDEV_DISABLE_DISK_RULES_FLAG}="1"
 ENV{DM_UDEV_DISABLE_OTHER_RULES_FLAG}="1"
 OPTIONS:="nowatch"

 LABEL="dm_end"
	# Copyright (C) 2009 Red Hat, Inc. All rights reserved.
	#
	# This file is part of LVM2.

	# Udev rules for device-mapper devices.
	#
	# These rules create a DM control node in /dev/(DM_DIR) directory.
	# The rules also create nodes named dm-x (x is a number) in /dev
	# directory and symlinks to these nodes with names given by
	# the actual DM names. Some udev environment variables are set
	# for use in later rules:
	# DM_NAME - actual DM device's name
	# DM_UUID - UUID set for DM device (blank if not specified)
	# DM_SUSPENDED - suspended state of DM device (0 or 1)
	# DM_UDEV_RULES_VSN - DM udev rules version
	#
	# These rules cover only basic device-mapper functionality in udev.
	#
	# Various DM subsystems may contain further subsystem-specific rules
	# in 11-dm-<subsystem_name>.rules which should be installed together
	# with the DM subsystem and which extend these basic rules.
	# For example:
	# 11-dm-lvm.rules for LVM subsystem
	# 11-dm-mpath.rules for multipath subsystem (since version 0.6.0, recommended!)
	#
	# Even more specific rules may be required by subsystems so always
	# check subsystem's upstream repository for recent set of rules.
	# Also, keep in mind that recent rules may also require recent
	# subsystem-specific binaries.

	KERNEL=="device-mapper", NAME="(DM_DIR)/control"

	SUBSYSTEM!="block", GOTO="dm_end"
	KERNEL!="dm-[0-9]*", GOTO="dm_end"
	(DM_EXEC_RULE)

	# Device created, major and minor number assigned - "add" event generated.
	# Table loaded - no event generated.
	# Device resumed (or renamed) - "change" event generated.
	# Device removed - "remove" event generated.
	#
	# The dm-X nodes are always created, even on "add" event, we can't suppress
	# that (the node is created even earlier with devtmpfs). All the symlinks
	# (e.g. /dev/mapper) are created in right time after a device has its table
	# loaded and is properly resumed. For this reason, direct use of dm-X nodes
	# is not recommended.
	ACTION!="add\|change", GOTO="dm_end"

	# Decode udev control flags and set environment variables appropriately.
	# These flags are encoded in DM_COOKIE variable that was introduced in
	# kernel version 2.6.31. Therefore, we can use this feature with
	# kernels >= 2.6.31 only. Cookie is not decoded for remove event.
	ENV{DM_COOKIE}=="?*", IMPORT{program}="(DM_EXEC)/dmsetup udevflags $env{DM_COOKIE}"

	# Rule out easy-to-detect inappropriate events first.
	ENV{DISK_RO}=="1", GOTO="dm_disable"

	# There is no cookie set nor any flags encoded in events not originating
	# in libdevmapper so we need to detect this and try to behave correctly.
	# For such spurious events, regenerate all flags from current udev database content
	# (this information would normally be inaccessible for spurious ADD and CHANGE events).
	ENV{DM_UDEV_PRIMARY_SOURCE_FLAG}=="1", ENV{DM_ACTIVATION}="1", GOTO="dm_flags_done"
	IMPORT{db}="DM_UDEV_DISABLE_DM_RULES_FLAG"
	IMPORT{db}="DM_UDEV_DISABLE_SUBSYSTEM_RULES_FLAG"
	IMPORT{db}="DM_UDEV_DISABLE_DISK_RULES_FLAG"
	IMPORT{db}="DM_UDEV_DISABLE_OTHER_RULES_FLAG"
	IMPORT{db}="DM_UDEV_LOW_PRIORITY_FLAG"
	IMPORT{db}="DM_UDEV_DISABLE_LIBRARY_FALLBACK_FLAG"
	IMPORT{db}="DM_UDEV_PRIMARY_SOURCE_FLAG"
	IMPORT{db}="DM_UDEV_FLAG7"
	IMPORT{db}="DM_UDEV_RULES_VSN"
	LABEL="dm_flags_done"

	# Normally, we operate on "change" events. But when coldplugging, there's an
	# "add" event present. We have to recognize this and do our actions in this
	# particular situation, too. Also, we don't want the nodes to be created
	# prematurely on "add" events while not coldplugging. We check
	# DM_UDEV_PRIMARY_SOURCE_FLAG to see if the device was activated correctly
	# before and if not, we ignore the "add" event totally. This way we can support
	# udev triggers generating "add" events (e.g. "udevadm trigger --action=add" or
	# "echo add > /sys/block/<dm_device>/uevent"). The trigger with "add" event is
	# also used at boot to reevaluate udev rules for all existing devices activated
	# before (e.g. in initrd). If udev is used in initrd, we require the udev init
	# script to not remove the existing udev database so we can reuse the information
	# stored at the time of device activation in the initrd.
	ACTION!="add", GOTO="dm_no_coldplug"
	ENV{DM_UDEV_RULES_VSN}!="1", ENV{DM_UDEV_PRIMARY_SOURCE_FLAG}!="1", GOTO="dm_disable"
	ENV{DM_ACTIVATION}="1"
	LABEL="dm_no_coldplug"

	# Putting it together, following table is used to recognize genuine and spurious events.
	# N.B. Spurious events are generated based on use of the WATCH udev
	# rule or by triggering an event manually by "udevadm trigger" call
	# or by "echo <event_name> > /sys/block/dm-X/uevent".
	#
	# EVENT DM_UDEV_PRIMARY_SOURCE_FLAG DM_ACTIVATION
	# ======================================================================
	# add event (genuine) 0 0
	# change event (genuine) 1 1
	# add event (spurious)
	# \|_ dev still not active 0 0
	# \_ dev already active 1 1
	# change event (spurious)
	# \|_ dev still not active 0 0
	# \_ dev already active 1 0

	# "dm" sysfs subdirectory is available in newer versions of DM
	# only (kernels >= 2.6.29). We have to check for its existence
	# and use dmsetup tool instead to get the DM name, uuid and
	# suspended state if the "dm" subdirectory is not present.
	# The "suspended" item was added even later (kernels >= 2.6.31),
	# so we also have to call dmsetup if the kernel version used
	# is in between these releases.
	TEST=="dm", ENV{DM_NAME}="$attr{dm/name}", ENV{DM_UUID}="$attr{dm/uuid}", ENV{DM_SUSPENDED}="$attr{dm/suspended}"
	TEST!="dm", IMPORT{program}="(DM_EXEC)/dmsetup info -j %M -m %m -c --nameprefixes --noheadings --rows -o name,uuid,suspended"
	ENV{DM_SUSPENDED}!="?*", IMPORT{program}="(DM_EXEC)/dmsetup info -j %M -m %m -c --nameprefixes --noheadings --rows -o suspended"

	# dmsetup tool provides suspended state information in textual
	# form with values "Suspended"/"Active". We translate it to
	# 0/1 respectively to be consistent with sysfs values.
	ENV{DM_SUSPENDED}=="Active", ENV{DM_SUSPENDED}="0"
	ENV{DM_SUSPENDED}=="Suspended", ENV{DM_SUSPENDED}="1"

	# This variable provides a reliable way to check that device-mapper
	# rules were installed. It means that all needed variables are set
	# by these rules directly so there's no need to acquire them again
	# later. Other rules can alternate the functionality based on this
	# fact (e.g. fallback to rules that behave correctly even without
	# these rules installed). It also provides versioning for any
	# possible future changes.
	# VSN 1 - original rules
	# VSN 2 - add support for synthesized events
	ENV{DM_UDEV_RULES_VSN}="2"

	ENV{DM_UDEV_DISABLE_DM_RULES_FLAG}!="1", ENV{DM_NAME}=="?*", SYMLINK+="(DM_DIR)/$env{DM_NAME}"

	# Avoid processing and scanning a DM device in the other (foreign)
	# rules if it is in suspended state. However, we still keep 'disk'
	# and 'DM subsystem' related rules enabled in this case.
	ENV{DM_SUSPENDED}=="1", ENV{DM_UDEV_DISABLE_OTHER_RULES_FLAG}="1"

	GOTO="dm_end"

	LABEL="dm_disable"
	ENV{DM_UDEV_DISABLE_SUBSYSTEM_RULES_FLAG}="1"
	ENV{DM_UDEV_DISABLE_DISK_RULES_FLAG}="1"
	ENV{DM_UDEV_DISABLE_OTHER_RULES_FLAG}="1"
	OPTIONS:="nowatch"

	LABEL="dm_end"