Document SPL module parameters.

This is a first draft of a spl-module-parameters(5) man page. I have
just extracted the parameter name and its description with modinfo,
then checked the source what type it is and its default value.

This will need more work, preferably someone that actually know these
values and what to use them for.  Similar to zfsonlinux/zfs#1856, but
for the spl.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes zfsonlinux/zfs#1856

configure.ac

@@ -50,6 +50,7 @@ AC_CONFIG_FILES([
 	Makefile
 	man/Makefile
 	man/man1/Makefile
+	man/man5/Makefile
 	lib/Makefile
 	cmd/Makefile
 	module/Makefile

man/Makefile.am

@@ -1 +1 @@
-SUBDIRS = man1
+SUBDIRS = man1 man5

man/man5/Makefile.am

@@ -0,0 +1,5 @@
+man_MANS = spl-module-parameters.5
+EXTRA_DIST = $(man_MANS)
+
+install-data-local:
+	$(INSTALL) -d -m 0755 "$(DESTDIR)$(mandir)/man5"

man/man5/spl-module-parameters.5

@@ -0,0 +1,126 @@
+'\" te
+.\"
+.\" Copyright 2013 Turbo Fredriksson <turbo@bayour.com>. All rights reserved.
+.\"
+.TH SPL-MODULE-PARAMETERS 5 "Nov 18, 2013"
+.SH NAME
+spl\-module\-parameters \- SPL module parameters
+.SH DESCRIPTION
+.sp
+.LP
+Description of the different parameters to the SPL module.
+
+.SS "Module parameters"
+.sp
+.LP
+
+.sp
+.ne 2
+.na
+\fBspl_debug_subsys\fR (ulong)
+.ad
+.RS 12n
+Subsystem debugging level mask.
+.sp
+Default value: \fB~0\fR.
+.RE
+
+.sp
+.ne 2
+.na
+\fBspl_debug_mask\fR (ulong)
+.ad
+.RS 12n
+Debugging level mask.
+.sp
+Default value: \fB8 | 10 | 4 | 20\fR (SD_ERROR | SD_EMERG | SD_WARNING | SD_CONSOLE).
+.RE
+
+.sp
+.ne 2
+.na
+\fBspl_debug_printk\fR (ulong)
+.ad
+.RS 12n
+Console printk level mask.
+.sp
+Default value: \fB8 | 10 | 4 | 20\fR (SD_ERROR | SD_EMERG | SD_WARNING | SD_CONSOLE).
+.RE
+
+.sp
+.ne 2
+.na
+\fBspl_debug_mb\fR (int)
+.ad
+.RS 12n
+Total debug buffer size.
+.sp
+Default value: \fB-1\fR.
+.RE
+
+.sp
+.ne 2
+.na
+\fBspl_debug_panic_on_bug\fR (int)
+.ad
+.RS 12n
+Panic on BUG
+.sp
+Use \fB1\fR for yes and \fB0\fR for no (default).
+.RE
+
+.sp
+.ne 2
+.na
+\fBspl_kmem_cache_expire\fR (uint)
+.ad
+.RS 12n
+By age (0x1) or low memory (0x2)
+.sp
+Default value: \fB0\fR.
+.RE
+
+.sp
+.ne 2
+.na
+\fBspl_hostid\fR (ulong)
+.ad
+.RS 12n
+The system hostid.
+.sp
+Default value: \fB0xFFFFFFFF\fR (an invalid hostid!)
+.RE
+
+.sp
+.ne 2
+.na
+\fBspl_hostid_path\fR (charp)
+.ad
+.RS 12n
+The system hostid file
+.sp
+Default value: \fB/etc/hostid\fR.
+.RE
+
+.sp
+.ne 2
+.na
+\fBmutex_spin_max\fR (int)
+.ad
+.RS 12n
+Spin a maximum of N times to acquire lock
+.sp
+.ne 2
+.na
+\fBPossible values:\fR
+.sp
+.RS 12n
+ \fB0\fR		Never spin when trying to acquire lock
+.sp
+\fB-1\fR		Spin until acquired or holder yields without dropping lock
+.sp
+\fB1-MAX_INT\fR	Spin for N attempts before sleeping for lock
+.RE
+.sp
+.ne -4
+Default value: \fB0\fR.

rpm/generic/spl.spec.in

@@ -35,6 +35,7 @@ make install DESTDIR=%{?buildroot}
 %doc AUTHORS COPYING DISCLAIMER
 %{_sbindir}/*
 %{_mandir}/man1/*
+%{_mandir}/man5/*
 
 %changelog
 * Wed Aug 21 2013 Brian Behlendorf <behlendorf1@llnl.gov> - 0.6.2-1