man: Revise internal man page generation process.

For each section 8 man page, a .8_gen file is created from one of:
  .8_main            - Old-style man page - content used directly
  .8_des and .8_end  - Description and end section of a generated page
  .8_pregen	     - Pre-generated page used if the generator fails

Other man sections are not generated and use the suffix .5_main or .7_main.

Developers should use 'make generate' to regenerate the .8_pregen files.

1 files changed, 39 insertions, 0 deletions

diff --git a/man/lvcreate.8_des b/man/lvcreate.8_des
new file mode 100644
index 000000000..acc07b300
--- /dev/null
+++ b/man/lvcreate.8_des
@@ -0,0 +1,39 @@
+lvcreate creates a new LV in a VG. For standard LVs, this requires
+allocating logical extents from the VG's free physical extents. If there
+is not enough free space, then the VG can be extended (see
+\fBvgextend\fP(8)) with other PVs, or existing LVs can be reduced or
+removed (see \fBlvremove\fP, \fBlvreduce\fP.)
+
+To control which PVs a new LV will use, specify one or more PVs as
+position args at the end of the command line. lvcreate will allocate
+physical extents only from the specified PVs.
+
+lvcreate can also create snapshots of existing LVs, e.g. for backup
+purposes. The data in a new snapshot LV represents the content of the
+original LV from the time the snapshot was created.
+
+RAID LVs can be created by specifying an LV type when creating the LV (see
+\fBlvmraid\fP(7)). Different RAID levels require different numbers of
+unique PVs be available in the VG for allocation.
+
+Thin pools (for thin provisioning) and cache pools (for caching) are
+represented by special LVs with types thin-pool and cache-pool (see
+\fBlvmthin\fP(7) and \fBlvmcache\fP(7)). The pool LVs are not usable as
+standard block devices, but the LV names act references to the pools.
+
+Thin LVs are thinly provisioned from a thin pool, and are created with a
+virtual size rather than a physical size. A cache LV is the combination of
+a standard LV with a cache pool, used to cache active portions of the LV
+to improve performance.
+
+.SS Usage notes
+
+In the usage section below, \fB--size\fP \fISize\fP can be replaced
+with \fB--extents\fP \fINumber\fP.  See both descriptions
+the options section.
+
+In the usage section below, \fB--name\fP is omitted from the required
+options, even though it is typically used.  When the name is not
+specified, a new LV name is generated with the "lvol" prefix and a unique
+numeric suffix.  Also see the description in the options section.
+