doc: describe lvmlockd/lvmpolld features as available if LVM compiled with lockd/polld support

conf/example.conf.in

@@ -853,11 +853,14 @@ global {
 
 	# Configuration option global/use_lvmlockd.
 	# Use lvmlockd for locking among hosts using LVM on shared storage.
-	# See lvmlockd(8) for more information.
+	# Applicable only if LVM is compiled with lockd support in which
+	# case there is also lvmlockd(8) man page available for more
+	# information.
 	use_lvmlockd = 0
 
 	# Configuration option global/lvmlockd_lock_retries.
 	# Retry lvmlockd lock requests this many times.
+	# Applicable only if LVM is compiled with lockd support
 	# This configuration option has an automatic default value.
 	# lvmlockd_lock_retries = 3
 
@@ -867,7 +870,8 @@ global {
 	# LVs have been created, the internal LV needs to be extended. lvcreate
 	# will automatically extend the internal LV when needed by the amount
 	# specified here. Setting this to 0 disables the automatic extension
-	# and can cause lvcreate to fail.
+	# and can cause lvcreate to fail. Applicable only if LVM is compiled
+	# with lockd support
 	# This configuration option has an automatic default value.
 	# sanlock_lv_extend = 256
 
@@ -1014,6 +1018,7 @@ global {
 	# a native systemd service, which allows it to be started on demand,
 	# and to use its own control group. When this option is disabled, LVM
 	# commands will supervise long running operations by forking themselves.
+	# Applicable only if LVM is compiled with lvmpolld support.
 	use_lvmpolld = @DEFAULT_USE_LVMPOLLD@
 
 	# Configuration option global/notify_dbus.

conf/lvmlocal.conf.in

@@ -51,6 +51,7 @@ local {
 	# Configuration option local/host_id.
 	# The lvmlockd sanlock host_id.
 	# This must be unique among all hosts, and must be between 1 and 2000.
+	# Applicable only if LVM is compiled with lockd support
 	# This configuration option has an automatic default value.
 	# host_id = 0
 }

lib/config/config_settings.h

@@ -856,10 +856,13 @@ cfg(global_use_lvmetad_CFG, "use_lvmetad", global_CFG_SECTION, 0, CFG_TYPE_BOOL,
 
 cfg(global_use_lvmlockd_CFG, "use_lvmlockd", global_CFG_SECTION, 0, CFG_TYPE_BOOL, 0, vsn(2, 2, 124), NULL, 0, NULL,
 	"Use lvmlockd for locking among hosts using LVM on shared storage.\n"
-	"See lvmlockd(8) for more information.\n")
+	"Applicable only if LVM is compiled with lockd support in which\n"
+	"case there is also lvmlockd(8) man page available for more\n"
+	"information.\n")
 
 cfg(global_lvmlockd_lock_retries_CFG, "lvmlockd_lock_retries", global_CFG_SECTION, CFG_DEFAULT_COMMENTED, CFG_TYPE_INT, DEFAULT_LVMLOCKD_LOCK_RETRIES, vsn(2, 2, 125), NULL, 0, NULL,
-	"Retry lvmlockd lock requests this many times.\n")
+	"Retry lvmlockd lock requests this many times.\n"
+	"Applicable only if LVM is compiled with lockd support\n")
 
 cfg(global_sanlock_lv_extend_CFG, "sanlock_lv_extend", global_CFG_SECTION, CFG_DEFAULT_COMMENTED, CFG_TYPE_INT, DEFAULT_SANLOCK_LV_EXTEND_MB, vsn(2, 2, 124), NULL, 0, NULL,
 	"Size in MiB to extend the internal LV holding sanlock locks.\n"
@@ -867,7 +870,8 @@ cfg(global_sanlock_lv_extend_CFG, "sanlock_lv_extend", global_CFG_SECTION, CFG_D
 	"LVs have been created, the internal LV needs to be extended. lvcreate\n"
 	"will automatically extend the internal LV when needed by the amount\n"
 	"specified here. Setting this to 0 disables the automatic extension\n"
-	"and can cause lvcreate to fail.\n")
+	"and can cause lvcreate to fail. Applicable only if LVM is compiled\n"
+	"with lockd support\n")
 
 cfg(global_thin_check_executable_CFG, "thin_check_executable", global_CFG_SECTION, CFG_ALLOW_EMPTY | CFG_DEFAULT_COMMENTED, CFG_TYPE_STRING, THIN_CHECK_CMD, vsn(2, 2, 94), "@THIN_CHECK_CMD@", 0, NULL,
 	"The full path to the thin_check command.\n"
@@ -993,7 +997,8 @@ cfg(global_use_lvmpolld_CFG, "use_lvmpolld", global_CFG_SECTION, 0, CFG_TYPE_BOO
 	"manage the progress of ongoing operations. lvmpolld can be used as\n"
 	"a native systemd service, which allows it to be started on demand,\n"
 	"and to use its own control group. When this option is disabled, LVM\n"
-	"commands will supervise long running operations by forking themselves.\n")
+	"commands will supervise long running operations by forking themselves.\n"
+	"Applicable only if LVM is compiled with lvmpolld support.\n")
 
 cfg(global_notify_dbus_CFG, "notify_dbus", global_CFG_SECTION, 0, CFG_TYPE_BOOL, DEFAULT_NOTIFY_DBUS, vsn(2, 2, 145), NULL, 0, NULL,
 	"Enable D-Bus notification from LVM commands.\n"
@@ -1779,6 +1784,7 @@ cfg_array(local_extra_system_ids_CFG, "extra_system_ids", local_CFG_SECTION, CFG
 
 cfg(local_host_id_CFG, "host_id", local_CFG_SECTION, CFG_DEFAULT_COMMENTED, CFG_TYPE_INT, 0, vsn(2, 2, 124), NULL, 0, NULL,
 	"The lvmlockd sanlock host_id.\n"
-	"This must be unique among all hosts, and must be between 1 and 2000.\n")
+	"This must be unique among all hosts, and must be between 1 and 2000.\n"
+	"Applicable only if LVM is compiled with lockd support\n")
 
 cfg(CFG_COUNT, NULL, root_CFG_SECTION, 0, CFG_TYPE_INT, 0, vsn(0, 0, 0), NULL, 0, NULL, NULL)

man/lvm.8.in

@@ -373,7 +373,8 @@ is not used and metadata is read from disks.
 .br
 Cause the command to access shared VGs, that would otherwise be skipped
 when lvmlockd is not being used.  It can be used to report or display a
-lockd VG without locking.
+lockd VG without locking. Applicable only if LVM is compiled with lockd
+support.
 .
 .HP
 .BR \-\-addtag

man/lvmsystemid.7.in

@@ -111,7 +111,8 @@ owned.
 .B Shared:
 A shared or "lockd" VG has lock_type set and no system_id.
 A shared VG is meant to be used on shared storage from multiple hosts,
-and is only accessible to hosts using lvmlockd.
+and is only accessible to hosts using lvmlockd. Applicable only if LVM
+is compiled with lockd support.
 
 .B Clustered:
 A clustered or "clvm" VG has the clustered flag set and no system_id.
@@ -308,7 +309,8 @@ extra_system_ids list.
 
 A shared/lockd VG has no system_id set, allowing multiple hosts to
 use it via lvmlockd.  Changing a VG to a lockd type will clear the
-existing system_id.
+existing system_id. Applicable only if LVM is compiled with lockd
+support.
 
 .SS clustered VGs
 

man/vgchange.8.in

@@ -132,8 +132,8 @@ be used on one node at once.
 
 For local VGs, \-ay, \-aey, and \-asy are all equivalent.
 .IP
-In a shared VG, lvmlockd is used for locking, and the following options
+In a shared VG, lvmlockd is used for locking if LVM is compiled with lockd
-are possible:
+support, and the following options are possible:
 
 With \-aey, the command activates the LV in exclusive mode, allowing a
 single host to activate the LV (the host running the command).  Before

man/vgcreate.8.in

@@ -130,10 +130,10 @@ The 2.4 kernel has a limitation of 2TiB per block device.
 
 .TP
 .B \-\-shared
-Create a shared VG using lvmlockd.  lvmlockd will select lock type sanlock
+Create a shared VG using lvmlockd if LVM is copiled with lockd support.
-or dlm depending on which lock manager is running.  This allows multiple
+ lvmlockd will select lock type sanlock or dlm depending on which lock
-hosts to share a VG on shared devices.  lvmlockd and a lock manager must
+manager is running.  This allows multiple hosts to share a VG on shared
-be configured and running.  See
+devices.  lvmlockd and a lock manager must be configured and running.  See
 .BR lvmlockd (8).
 
 .TP