sanlvm: update

Signed-off-by: David Teigland <teigland@redhat.com>

1 files changed, 206 insertions, 65 deletions

diff --git a/lvm/sanlvm b/lvm/sanlvm
index 511fc57..4594db9 100755
--- a/lvm/sanlvm
+++ b/lvm/sanlvm
@@ -2,6 +2,7 @@
 
 host_id=0
 cmd=
+glpath=
 vgname=
 lvname=
 lock_mode=
@@ -9,38 +10,76 @@ active_mode=
 no_active=
 offset=
 
+# sanlvmd is only needed when sanlvm is used with lv
+# activation leases.  When sanlvm is only used to
+# serialize vg metadata changes, it's not needed.
+#
+# sanlvmd is a process that sanlock views as owning the lv
+# activation leases.  When a vg disappears/fails, sanlock
+# will notify the owner of the leases in that vg; in this
+# case, it sends SIGTERM to sanlvmd.  When sanlvmd gets
+# this SIGTERM, it knows that its leases will be disappearing
+# soon, and that another host would be able to acquire them.
+# So, it needs to force the local host to stop using the
+# lv's it has locked, since they won't be locked much longer.
+#
+# To do this, it could:
+# - forcibly deactivate the sanlvm lvs in the failed vgs
+# - suspend the lv's in the failed vgs
+# - or suspend lv's, replace with the error target and resume
+# and once done, it can release the leases on those lvs.
+#
+# (If the sanlock watchdog is enabled, it will fire to reset
+# the host if sanlvmd is not able to release the leases
+# before another host could acquire them.)
+#
+# If the lv's are suspended, sanlvmd could monitor and wait
+# for the vg to reappear.  When it does, it could reacquire
+# the leases for the suspended lv's and then resume the lv's.
+# (Unless the leases have been acquired by another host since
+# they were released, in which case they cannot be reacquired
+# by the oringal host, and the lv's will not be resumed.)
+
 help() {
 	vg="\$vg"
 	host_id="\$host_id"
 	echo ""
-	echo "1. /etc/sanlvm.conf"
+	echo "/etc/sanlvm.conf"
 	echo "   must contain unique host_id definition from 1 to 2000, e.g."
 	echo "   host_id 1"
 	echo ""
-	echo "2. sanlvm vgcreate [options] $vg <devs>"
+	echo "sanlvm vgcreate [options] $vg <devs>"
 	echo "   create vg, unprotected by sanlock,"
 	echo "   create and initialize storage in $vg for sanlock to use"
-	echo "   vgcreate [options] $vg <devs>"
-	echo "   lvcreate -n leases -L 1G $vg"
-	echo "   sanlock direct init -s $vg:0:/dev/$vg/leases:0"
-	echo "   sanlock direct init -r $vg:vglk:/dev/$vg/leases:1048576"
-	echo "   vgchange --addtag @sanlvm $vg"
+	echo "   . vgcreate [options] $vg <devs>"
+	echo "   . lvcreate -n leases -L 1G $vg"
+	echo "   . sanlock direct init -s $vg:0:/dev/$vg/leases:0"
+	echo "   . sanlock direct init -r $vg:vglk:/dev/$vg/leases:1048576"
+	echo "   . vgchange --addtag @sanlvm $vg"
 	echo ""
-	echo "3. sanlvm start"
+	echo "sanlvm start"
 	echo "   start lockspaces for vgs @sanlvm, created above"
-	echo "   sanlock add_lockspace -s $vg:$host_id:/dev/$vg/leases:0"
+	echo "   . sanlock add_lockspace -s $vg:$host_id:/dev/$vg/leases:0"
 	echo ""
-	echo "4. sanlvm <lvmcmd> ..."
+	echo "sanlvm <lvmcmd> ..."
 	echo "   lvm commands within $vg are serialized by sanlock"
-	echo "   sanlock command -r $vg:vglk:/dev/$vg/leases:1048576 -c /sbin/lvm <lvmcmd> ..."
+	echo "   . sanlock command -r $vg:vglk:/dev/$vg/leases:1048576 -c /sbin/lvm <lvmcmd> ..."
 	echo ""
-
-	echo "sanlvm vgcreate [options] $vg <devs>"
-	echo "sanlvm start"
 	echo "sanlvm [--na] lvcreate ..."
-	echo "sanlvm lvextend|lvreduce|lvremove ..."
+	echo "   create an lv with or without (--na) an associated lv"
+	echo "   activation lease.  without an activation lease, the"
+	echo "   the activation state among hosts is ignored."
+	echo ""
 	echo "sanlvm --sh|ex lvchange -ay ..."
+	echo "   acquire a shared or exclusive lease, then activate the lv."
+	echo "   an exclusive lease prevents more than one host from activating"
+	echo "   the lv at once, a shared lease allows multiple hosts to"
+	echo "   activate the lv at once, and prevents any from activating"
+	echo "   it exclusively."
+	echo ""
 	echo "sanlvm lvchange -an ..."
+	echo "   deactivate the lv, then release its lease"
+	echo ""
 	exit 0
 }
 
@@ -71,7 +110,7 @@ fi
 get_vg_name() {
 	prev=$2
 
-	for i in $args
+	for i in $get_args
 	do 
 		first=`expr substr $i 1 1`
 		if [[ "$first" == "/" ]]; then
@@ -82,7 +121,7 @@ get_vg_name() {
 		prev=$i
 	done
 
-	for i in $args
+	for i in $get_args
 	do 
 		vgname=$i
 	done
@@ -94,7 +133,7 @@ get_vg_name() {
 get_lv_name() {
 	save_next=0
 
-	for i in $args
+	for i in $get_args
 	do 
 		if [[ $save_next == 1 ]]; then
 			lvname=$i
@@ -112,7 +151,7 @@ get_lv_name() {
 # first arg containing '/'
 
 get_vg_lv_name() {
-	for i in $args
+	for i in $get_args
 	do 
 		ind=`expr index $i /`
 		if [ $ind -gt 0 ]; then
@@ -133,12 +172,20 @@ get_host_id() {
 	fi
 }
 
+get_global_lease() {
+	glpath=`awk '/^global_lease_path/ { print $2 }' < /etc/sanlvm.conf`
+
+	if [[ $? -ne 0 ]]; then
+		echo "no global_lease_path found in /etc/sanlvm.conf"
+	fi
+}
+
 # search lvchange args for -a, ---available
 # if there's a "y" anywhere after the option, then active_mode="y"
 # if there's a "n" anywhere after the option, then active_mode="n"
 
 get_active_mode() {
-	for i in $args
+	for i in $get_args
 	do 
 		if [[ "$i" == "-ay" ]] || [[ "$i" == "-aly" ]] || [[ "$i" == "-aey" ]]; then
 			active_mode="y"
@@ -181,21 +228,54 @@ get_lease_offset() {
 	offset=`echo $tags | cut --delimiter=_ --fields=3`
 }
 
-if [[ "$cmd" == "start" ]]; then
+if [[ "$cmd" == "global_init" ]]; then
+	get_global_lease
+
+	if [[ "$glpath" == "" ]]; then
+		exit 1
+	fi
+
+	sanlock direct init -s sanlvm_global:0:$glpath:0
+
+	if [[ $? -ne 0 ]]; then
+		exit 1
+	fi
+
+	sanlock direct init -r sanlvm_global:lease:$glpath:1048576
+
+	if [[ $? -ne 0 ]]; then
+		exit 1
+	fi
+
+	exit 0
+
+elif [[ "$cmd" == "start" ]]; then
+	get_global_lease
 	get_host_id
 
+	if [[ "$glpath" != "" ]]; then
+		lvm lvchange -a y $glpath
+		sanlock add_lockspace -s sanlvm_global:$host_id:$glpath:0
+	fi
+
 	for vgname in `vgs @sanlvm --noheadings -o vg_name`; do
+		# FIXME: do something to prevent sanlvm lv's from
+		# automatically being activated by the system at
+		# startup; then this vgchange -an is not needed.
+		vgchange -an $vgname
+
 		lvm lvchange -a y /dev/$vgname/leases
 		echo adding lockspace $vgname, this may take minutes...
 		sanlock add_lockspace -s $vgname:$host_id:/dev/$vgname/leases:0
 	done
 
 	exit 0
-fi
 
-if [[ "$cmd" == "vgcreate" ]]; then
-	args=$*
+elif [[ "$cmd" == "vgcreate" ]]; then
 
+	# FIXME: wrap this function in sanlvm_global:lease
+
+	get_args=$*
 	get_vg_name
 
 	lvm "$@"
@@ -230,20 +310,94 @@ if [[ "$cmd" == "vgcreate" ]]; then
 
 	exit 0
 
+elif [[ "$cmd" == "vgextend" ]]; then
+
+	get_args=$*
+	get_vg_name
+	get_glpath
+
+	# FIXME: take both global lease and vglk, e.g.
+	# sanlock command -r sanlvm_global:lease:$glpath:1048576 -r $vgname:vglk:/dev/$vgname/leases:1048576 -c /sbin/lvm "$@"
+
+	sanlock command -r $vgname:vglk:/dev/$vgname/leases:1048576 -c /sbin/lvm "$@"
+
+	if [[ $? -ne 0 ]]; then
+		exit 1
+	fi
+
+	exit 0
+
+elif [[ "$cmd" == "vgremove" ]]; then
+
+
+	get_args=$*
+	get_vg_name
+	get_glpath
+
+	# It doesn't work to hold the vglk around vgremove, because
+	# the vglk requires the leases lv to be open, which causes
+	# the vgremove to fail.  This is similar to the reason we can't
+	# hold the vglk around vgcreate: the leases area for vglk doesn't
+	# exist yet because it's inside the vg being created.
+
+	# FIXME: we could do the lvremoves automatically,
+	# but it looks messy
+
+	found=0
+
+	for lvname in `lvs $vgname --noheadings -o lv_name`; do
+		if [[ "$lvname" != "leases" ]]; then
+			echo "run sanlvm lvremove $vgname/$lvname before vgremove"
+			found=1
+		fi
+	done
+
+	if [[ $found -eq 1 ]]; then
+		exit 1
+	fi
+
+	# FIXME: wrap vgremove in sanlvm_global:lease
+
+	lvm "$@"
+
+	if [[ $? -ne 0 ]]; then
+		exit 1
+	fi
+	
+	exit 0
+
+elif [[ "$cmd" == "vgchange" ]]; then
+
+	# FIXME: catch variations of vgchange -ay / -an
+	# and either prohibit (require sanlvm lvchange), or
+	# translate into sanlvm lvchange here.
+
+	lvm "$@"
+
+	if [[ $? -ne 0 ]]; then
+		exit 1
+	fi
+	
+	exit 0
+
 elif [[ "$cmd" == "_lvcreate" ]]; then
 	# wrapped by vglk
-
 	shift
 
-	args=$*
-
+	get_args=$*
 	get_vg_name
 	get_lv_name
 
-	# FIXME: get offset by searching leases lv for unused lease area
-	offset=2097152
+	offset=`sanlock direct next_free /dev/$vgname/leases`
+
+	if [[ $? -ne 0 ]]; then
+		echo "no space for new lease on /dev/$vgname/leases"
+		exit 1
+	fi
+
+	# FIXME: if we use recent lvcreate arg to disable activation,
+	# on creation, then we can remove the lvchange -an that follows.
 
-	# FIXME: use recent lvcreate arg to disable activation
 	# lvcreate
 	lvm "$@"
 
@@ -251,7 +405,6 @@ elif [[ "$cmd" == "_lvcreate" ]]; then
 		exit 1
 	fi
 
-	# FIXME: can remove this once lvcreate doesn't activate
 	lvm lvchange -an $vgname/$lvname
 
 	if [[ $? -ne 0 ]]; then
@@ -275,8 +428,7 @@ elif [[ "$cmd" == "_lvcreate" ]]; then
 elif [[ "$cmd" == "lvcreate" ]]; then
 	# we need the multiple steps in _lvcreate to all be wrapped in vglk
 
-	args=$*
-
+	get_args=$*
 	get_vg_name
 
 	if [[ "$no_active" == "--na" ]]; then
@@ -295,17 +447,13 @@ elif [[ "$cmd" == "lvcreate" ]]; then
 
 elif [[ "$cmd" == "_lvremove" ]]; then
 	# wrapped by vglk
-
 	shift
 
-	args=$*
-
 	vgname=$SANLVM_VGNAME
 	lvname=$SANLVM_LVNAME
 	offset=$SANLVM_OFFSET
 
-	# refuse to remove the lv if the local
-	# host has the lv activated
+	# refuse to remove the lv if the local host has the lv activated
 
 	status=`sanlock client status | grep "r $vgname:$lvname"`
 
@@ -314,9 +462,8 @@ elif [[ "$cmd" == "_lvremove" ]]; then
 		exit 1
 	fi
 
-	# acquire ex activation lock on the lv so
-	# we know that no hosts have it active
-	# FIXME: I don't think sanlock client acquire success/fail exit codes are always correct
+	# acquire ex activation lock on the lv so we know that no hosts have it active
+	# FIXME: I don't think sanlock acquire success/fail exit codes are always correct
 
 	sanlock client acquire -r $vgname:$lvname:/dev/$vgname/leases:$offset -p `pidof sanlvmd`
 
@@ -336,8 +483,8 @@ elif [[ "$cmd" == "_lvremove" ]]; then
 	exit 0
 
 elif [[ "$cmd" == "lvremove" ]]; then
-	args=$*
 
+	get_args=$*
 	get_vg_lv_name
 	get_lease_offset
 
@@ -357,18 +504,15 @@ elif [[ "$cmd" == "lvremove" ]]; then
 
 	exit 0
 
-elif [[ "$cmd" == "_lvextend" ]] || [[ "$cmd" == "_lvreduce" ]]; then
+elif [[ "$cmd" == "_lvextend" ]] || [[ "$cmd" == "_lvreduce" ]] || [[ "$cmd" == "_lvconvert" ]] || [[ "$cmd" == "_lvresize" ]]; then
 	# wrapped by vglk
-
 	shift
 
-	args=$*
-
 	vgname=$SANLVM_VGNAME
 	lvname=$SANLVM_LVNAME
 	offset=$SANLVM_OFFSET
 
-	# refuse to extend/reduce the lv if the local
+	# refuse to extend/reduce/convert the lv if the local
 	# host has the lv activated
 	# FIXME: allow extend of active lv, not reduce
 
@@ -389,7 +533,7 @@ elif [[ "$cmd" == "_lvextend" ]] || [[ "$cmd" == "_lvreduce" ]]; then
 		exit 1
 	fi
 
-	# lvextend/lvreduce
+	# lvextend/lvreduce/lvconvert
 	lvm "$@"
 
 	sanlock client release -r $vgname:$lvname:/dev/$vgname/leases:$offset -p `pidof sanlvmd`
@@ -397,9 +541,9 @@ elif [[ "$cmd" == "_lvextend" ]] || [[ "$cmd" == "_lvreduce" ]]; then
 	exit 0;
 
 
-elif [[ "$cmd" == "lvextend" ]] || [[ "$cmd" == "lvreduce" ]]; then
-	args=$*
+elif [[ "$cmd" == "lvextend" ]] || [[ "$cmd" == "lvreduce" ]] || [[ "$cmd" == "lvconvert" ]] || [[ "$cmd" == "lvresize" ]]; then
 
+	get_args=$*
 	get_vg_lv_name
 	get_lease_offset
 
@@ -420,15 +564,8 @@ elif [[ "$cmd" == "lvextend" ]] || [[ "$cmd" == "lvreduce" ]]; then
 	exit 0
 
 elif [[ "$cmd" == "lvchange" ]]; then
-	# sanlvmd is a process that sanlock views as owning the lv
-	# activation leases.  sanlvmd should restrict sigkill, and
-	# on sigterm from sanlock, it should try to forcibly deactivate
-	# the sanlvm lvs, or suspend the lv's or suspend lv's, replace
-	# with the error target and resume.
-	# (what about handling different vg lockspaces separately?)
-
-	args=$*
 
+	get_args=$*
 	get_vg_lv_name
 	get_active_mode
 	get_lease_offset
@@ -439,7 +576,6 @@ elif [[ "$cmd" == "lvchange" ]]; then
 	fi
 
 	if [[ "$active_mode" == "y" ]]; then
-		# acquire lease, then activate
 
 		if [[ "$lock_mode" == "--sh" ]]; then
 			suffix=":SH"
@@ -457,10 +593,9 @@ elif [[ "$cmd" == "lvchange" ]]; then
 		lvm "$@"
 
 	elif [[ "$active_mode" == "n" ]]; then
-		# deactivate, then release lease
 
-		# lock mode is not used for lvchange -an, and shouldn't be
-		# provided, but ignore it if it is
+		# lock mode is not used for lvchange -an,
+		# ignore it if one was provided
 
 		if [[ "$lock_mode" != "" ]]; then
 			shift
@@ -474,7 +609,6 @@ elif [[ "$cmd" == "lvchange" ]]; then
 		# non-activation related change to lv
 		# I don't know of any lv changes that would require either
 		# vglk or the lv lock
-		# sanlock command -r $vgname:vglk:/dev/$vgname/leases:1048576 -c /sbin/lvm "$@
 
 		echo "no locks needed for this command"
 		lvm "$@"
@@ -482,14 +616,21 @@ elif [[ "$cmd" == "lvchange" ]]; then
 
 	exit 0
 
+elif [[ "$cmd" == "vgmerge" ]] || [[ "$cmd" == "vgsplit" ]] || [[ "$cmd" == "vgrename" ]] || [[ "$cmd" == "lvrename" ]]; then
+
+	# FIXME: the vg commands could be implemented by combining
+	# a global lease and vglk's
+
+	echo "command not supported with sanlvm"
+	exit 1
+
 else
 	if [[ $# -lt 2 ]]; then
 		echo vg name required
 		exit 1
 	fi
 
-	args=$*
-
+	get_args=$*
 	get_vg_name
 
 	sanlock command -r $vgname:vglk:/dev/$vgname/leases:1048576 -c /sbin/lvm "$@"