[Buildroot] [PATCH 4/5] package/petitboot: enable discovery of software RAID devices

[Laurent Vivier]

Le 06/09/2023 à 21:46, Reza Arbab a écrit :
> Petitboot can support filesystems on software RAID arrays. If mdadm is
> selected, install the associated udev rules to assemble the device.
> 
> Signed-off-by: Reza Arbab <arbab at linux.ibm.com>
> ---
>   package/petitboot/63-md-raid-arrays.rules | 41 ++++++++++++++
>   package/petitboot/65-md-incremental.rules | 69 +++++++++++++++++++++++
>   package/petitboot/petitboot.mk            | 10 ++++
>   3 files changed, 120 insertions(+)
>   create mode 100644 package/petitboot/63-md-raid-arrays.rules
>   create mode 100644 package/petitboot/65-md-incremental.rules
> 
> diff --git a/package/petitboot/63-md-raid-arrays.rules b/package/petitboot/63-md-raid-arrays.rules
> new file mode 100644
> index 000000000000..92aec36e69d4
> --- /dev/null
> +++ b/package/petitboot/63-md-raid-arrays.rules
> @@ -0,0 +1,41 @@
> +# do not edit this file, it will be overwritten on update
> +
> +SUBSYSTEM!="block", GOTO="md_end"
> +
> +# handle md arrays
> +ACTION!="add|change", GOTO="md_end"
> +KERNEL!="md*", GOTO="md_end"
> +
> +# partitions have no md/{array_state,metadata_version}, but should not
> +# for that reason be ignored.
> +ENV{DEVTYPE}=="partition", GOTO="md_ignore_state"
> +
> +# container devices have a metadata version of e.g. 'external:ddf' and
> +# never leave state 'inactive'
> +ATTR{md/metadata_version}=="external:[A-Za-z]*", ATTR{md/array_state}=="inactive", GOTO="md_ignore_state"
> +TEST!="md/array_state", ENV{SYSTEMD_READY}="0", GOTO="md_end"
> +ATTR{md/array_state}=="|clear|inactive", ENV{SYSTEMD_READY}="0", GOTO="md_end"
> +LABEL="md_ignore_state"
> +
> +IMPORT{program}="/sbin/mdadm --detail --export $devnode"
> +ENV{DEVTYPE}=="disk", ENV{MD_NAME}=="?*", SYMLINK+="disk/by-id/md-name-$env{MD_NAME}", OPTIONS+="string_escape=replace"
> +ENV{DEVTYPE}=="disk", ENV{MD_UUID}=="?*", SYMLINK+="disk/by-id/md-uuid-$env{MD_UUID}"
> +ENV{DEVTYPE}=="disk", ENV{MD_DEVNAME}=="?*", SYMLINK+="md/$env{MD_DEVNAME}"
> +ENV{DEVTYPE}=="partition", ENV{MD_NAME}=="?*", SYMLINK+="disk/by-id/md-name-$env{MD_NAME}-part%n", OPTIONS+="string_escape=replace"
> +ENV{DEVTYPE}=="partition", ENV{MD_UUID}=="?*", SYMLINK+="disk/by-id/md-uuid-$env{MD_UUID}-part%n"
> +ENV{DEVTYPE}=="partition", ENV{MD_DEVNAME}=="*[^0-9]", SYMLINK+="md/$env{MD_DEVNAME}%n"
> +ENV{DEVTYPE}=="partition", ENV{MD_DEVNAME}=="*[0-9]", SYMLINK+="md/$env{MD_DEVNAME}p%n"
> +
> +IMPORT{builtin}="blkid"
> +OPTIONS+="link_priority=100"
> +OPTIONS+="watch"
> +ENV{ID_FS_USAGE}=="filesystem|other|crypto", ENV{ID_FS_UUID_ENC}=="?*", SYMLINK+="disk/by-uuid/$env{ID_FS_UUID_ENC}"
> +ENV{ID_FS_USAGE}=="filesystem|other", ENV{ID_FS_LABEL_ENC}=="?*", SYMLINK+="disk/by-label/$env{ID_FS_LABEL_ENC}"
> +
> +ENV{MD_LEVEL}=="raid[1-9]*", ENV{SYSTEMD_WANTS}+="mdmonitor.service"
> +
> +# Tell systemd to run mdmon for our container, if we need it.
> +ENV{MD_LEVEL}=="raid[1-9]*", ENV{MD_CONTAINER}=="?*", PROGRAM="/usr/bin/readlink $env{MD_CONTAINER}", ENV{MD_MON_THIS}="%c"
> +ENV{MD_MON_THIS}=="?*", PROGRAM="/usr/bin/basename $env{MD_MON_THIS}", ENV{SYSTEMD_WANTS}+="mdmon@%c.service"
> +
> +LABEL="md_end"
> diff --git a/package/petitboot/65-md-incremental.rules b/package/petitboot/65-md-incremental.rules
> new file mode 100644
> index 000000000000..153d12fe6f7e
> --- /dev/null
> +++ b/package/petitboot/65-md-incremental.rules
> @@ -0,0 +1,69 @@
> +# This file causes block devices with Linux RAID (mdadm) signatures to
> +# automatically cause mdadm to be run.
> +# See udev(8) for syntax
> +
> +# Don't process any events if anaconda is running as anaconda brings up
> +# raid devices manually
> +ENV{ANACONDA}=="?*", GOTO="md_end"
> +
> +# Also don't process disks that are slated to be a multipath device
> +ENV{DM_MULTIPATH_DEVICE_PATH}=="?*", GOTO="md_end"
> +
> +# We process add events on block devices (since they are ready as soon as
> +# they are added to the system), but we must process change events as well
> +# on any dm devices (like LUKS partitions or LVM logical volumes) and on
> +# md devices because both of these first get added, then get brought live
> +# and trigger a change event.  The reason we don't process change events
> +# on bare hard disks is because if you stop all arrays on a disk, then
> +# run fdisk on the disk to change the partitions, when fdisk exits it
> +# triggers a change event, and we want to wait until all the fdisks on
> +# all member disks are done before we do anything.  Unfortunately, we have
> +# no way of knowing that, so we just have to let those arrays be brought
> +# up manually after fdisk has been run on all of the disks.
> +
> +# First, process all add events (md and dm devices will not really do
> +# anything here, just regular disks, and this also won't get any imsm
> +# array members either)
> +SUBSYSTEM=="block", ACTION=="add|change", ENV{ID_FS_TYPE}=="linux_raid_member", \
> +	RUN+="/sbin/mdadm -I --export $env{DEVNAME}"
> +
> +# Next, check to make sure the BIOS raid stuff wasn't turned off via cmdline
> +IMPORT{cmdline}="noiswmd"
> +IMPORT{cmdline}="nodmraid"
> +ENV{noiswmd}=="?*", GOTO="md_imsm_inc_end"
> +ENV{nodmraid}=="?*", GOTO="md_imsm_inc_end"
> +SUBSYSTEM=="block", ACTION=="add", ENV{ID_FS_TYPE}=="isw_raid_member", \
> +	RUN+="/sbin/mdadm -I $env{DEVNAME}"
> +LABEL="md_imsm_inc_end"
> +
> +SUBSYSTEM=="block", ACTION=="remove", ENV{ID_PATH}=="?*", \
> +	RUN+="/sbin/mdadm -If $name --path $env{ID_PATH}"
> +SUBSYSTEM=="block", ACTION=="remove", ENV{ID_PATH}!="?*", \
> +	RUN+="/sbin/mdadm -If $name"
> +
> +# Next make sure that this isn't a dm device we should skip for some reason
> +ENV{DM_UDEV_RULES_VSN}!="?*", GOTO="dm_change_end"
> +ENV{DM_UDEV_DISABLE_OTHER_RULES_FLAG}=="1", GOTO="dm_change_end"
> +ENV{DM_SUSPENDED}=="1", GOTO="dm_change_end"
> +KERNEL=="dm-*", SUBSYSTEM=="block", ENV{ID_FS_TYPE}=="linux_raid_member", \
> +	ACTION=="change", RUN+="/sbin/mdadm -I $env{DEVNAME}"
> +LABEL="dm_change_end"
> +
> +# Finally catch any nested md raid arrays.  If we brought up an md raid
> +# array that's part of another md raid array, it won't be ready to be used
> +# until the change event that occurs when it becomes live
> +KERNEL=="md*", SUBSYSTEM=="block", ENV{ID_FS_TYPE}=="linux_raid_member", \
> +	ACTION=="change", RUN+="/sbin/mdadm -I $env{DEVNAME}"
> +
> +# In case the initramfs only started some of the arrays in our container,
> +# run incremental assembly on the container itself.  Note: we ran mdadm
> +# on the container in 64-md-raid.rules, and that's how the MD_LEVEL
> +# environment variable is already set.  If that disappears from the other
> +# file, we will need to add this line into the middle of the next rule:
> +#	IMPORT{program}="/sbin/mdadm -D --export $tempnode", \
> +
> +SUBSYSTEM=="block", ACTION=="add|change", KERNEL=="md*", \
> +	ENV{MD_LEVEL}=="container", RUN+="/sbin/mdadm -I $env{DEVNAME}"
> +
> +
> +LABEL="md_end"
> diff --git a/package/petitboot/petitboot.mk b/package/petitboot/petitboot.mk
> index 9326738aa038..596e801b781c 100644
> --- a/package/petitboot/petitboot.mk
> +++ b/package/petitboot/petitboot.mk
> @@ -46,6 +46,16 @@ else
>   PETITBOOT_CONF_OPTS += --without-fdt
>   endif
>   
> +ifeq ($(BR2_PACKAGE_MDADM),y)
> +define PETITBOOT_POST_INSTALL_MDADM
> +	$(INSTALL) -D -m 0755 $(PETITBOOT_PKGDIR)/63-md-raid-arrays.rules \
> +		$(TARGET_DIR)/etc/udev/rules.d/63-md-raid-arrays.rules
> +	$(INSTALL) -D -m 0755 $(PETITBOOT_PKGDIR)/65-md-incremental.rules \
> +		$(TARGET_DIR)/etc/udev/rules.d/65-md-incremental.rules
> +endef
> +PETITBOOT_POST_INSTALL_TARGET_HOOKS += PETITBOOT_POST_INSTALL_MDADM
> +endif
> +
>   define PETITBOOT_POST_INSTALL
>   	$(INSTALL) -D -m 0755 $(@D)/utils/bb-kexec-reboot \
>   		$(TARGET_DIR)/usr/libexec/petitboot/bb-kexec-reboot

Reviewed-by: Laurent Vivier <laurent at vivier.eu>