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 <[email protected]>
Closes zfsonlinux/zfs#1856

3 files changed, 132 insertions, 1 deletions

diff --git a/man/Makefile.am b/man/Makefile.am
index 7dc2a57d1..7791945cf 100644
--- a/man/Makefile.am
+++ b/man/Makefile.am
@@ -1 +1 @@
-SUBDIRS = man1
+SUBDIRS = man1 man5
diff --git a/man/man5/Makefile.am b/man/man5/Makefile.am
new file mode 100644
index 000000000..06a823325
--- /dev/null
+++ b/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"
diff --git a/man/man5/spl-module-parameters.5 b/man/man5/spl-module-parameters.5
new file mode 100644
index 000000000..3c134f775
--- /dev/null
+++ b/man/man5/spl-module-parameters.5
@@ -0,0 +1,126 @@
+'\" te
+.\"
+.\" Copyright 2013 Turbo Fredriksson <[email protected]>. 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.