From 5090c893b72d26193d4d4c923efe3affafbb3f4b Mon Sep 17 00:00:00 2001
From: "Kenneth D. Merry" <ken@FreeBSD.org>
Date: Tue, 3 Mar 2015 22:49:07 +0000
Subject: [PATCH] Add density code for DAT-72, and notes on DAT-160.

As it turns out, the density code for DAT-160 (0x48) is the same
as for SDLT220.  Since the SDLT values are already in the table,
we will leave them in place.

Thanks to Harald Schmalzbauer for confirming the DAT-72 density code.

lib/libmt/mtlib.c:
	Add DAT-72 density code, and commented out DAT-160 density
	code.  Explain why DAT-160 is commented out.  Add notes
	explaining where the bpi values for these formats came from.

usr.bin/mt/mt.1:
	Add DAT-72 density code, and add a note explaining that
	the SDLTTapeI(110) density code (0x48) is the same as
	DAT-160.

Sponsored by:	Spectra Logic
MFC after:	3 weeks
---
 lib/libmt/mtlib.c | 17 +++++++++++++++++
 usr.bin/mt/mt.1   |  6 ++++--
 2 files changed, 21 insertions(+), 2 deletions(-)

diff --git a/lib/libmt/mtlib.c b/lib/libmt/mtlib.c
index ad73381c5822..f6acba21f4ef 100644
--- a/lib/libmt/mtlib.c
+++ b/lib/libmt/mtlib.c
@@ -568,6 +568,15 @@ static struct densities {
 	 *
 	 * IBM 3592 definitions obtained from second edition of the IBM
 	 * System Storage Tape Drive 3592 SCSI Reference (May 25, 2012).
+	 *
+	 * DAT-72 and DAT-160 bpi values taken from "HP StorageWorks DAT160
+	 * tape drive white paper", dated June 2007.
+	 *
+	 * DAT-160 / SDLT220 density code (0x48) conflict information
+	 * found here:
+	 *
+	 * http://h20564.www2.hp.com/hpsc/doc/public/display?docId=emr_na-c01065117&sp4ts.oid=429311
+ 	 * (Document ID c01065117)
 	 */
 	/*Num.  bpmm    bpi     Reference     */
 	{ 0x1,	32,	800,	"X3.22-1983" },
@@ -613,6 +622,14 @@ static struct densities {
 	{ 0x42, 7398,   187909, "LTO-2" },
 	{ 0x44, 9638,   244805, "LTO-3" }, 
 	{ 0x46, 12725,  323215, "LTO-4" }, 
+	{ 0x47, 6417,   163000, "DAT-72" },
+	/*
+	 * XXX KDM note that 0x48 is also the density code for DAT-160.
+	 * For some reason they used overlapping density codes.
+	 */
+#if 0
+	{ 0x48, 6870,   174500, "DAT-160" },
+#endif
 	{ 0x48, 5236,   133000, "SDLTapeI(110)" },
 	{ 0x49, 7598,   193000, "SDLTapeI(160)" },
 	{ 0x4a,     0,       0, "T10000A" },
diff --git a/usr.bin/mt/mt.1 b/usr.bin/mt/mt.1
index 849774c5d74f..33c1c1814725 100644
--- a/usr.bin/mt/mt.1
+++ b/usr.bin/mt/mt.1
@@ -29,7 +29,7 @@
 .\"	@(#)mt.1	8.1 (Berkeley) 6/6/93
 .\" $FreeBSD$
 .\"
-.Dd February 12, 2014
+.Dd March 3, 2014
 .Dt MT 1
 .Os
 .Sh NAME
@@ -503,7 +503,8 @@ Value  Width        Tracks    Density         Code Type Reference   Note
 0x42   12.7  (0.5)  512      7,398  (187,909)       C   LTO-2
 0x44   12.7  (0.5)  704      9,638  (244,805)       C   LTO-3
 0x46   12.7  (0.5)  896      12,725 (323,215)       C   LTO-4
-0x48   12.7  (0.5)  448      5,236  (133,000) PRML  C   SDLTapeI(110) 6,8
+0x47    3.81 (0.25)   ?      6,417  (163,000)       CS  DAT-72
+0x48   12.7  (0.5)  448      5,236  (133,000) PRML  C   SDLTapeI(110) 6,8,13
 0x49   12.7  (0.5)  448      7,598  (193,000) PRML  C   SDLTapeI(160) 6,8
 0x4A   12.7  (0.5)  768          ?                  C   T10000A      10
 0x4B   12.7  (0.5) 1152          ?                  C   T10000B      10
@@ -556,6 +557,7 @@ NOTES
     density code is 0x90.
 12. This is Exabyte 8500 uncompressed format.  The compressed format
     density code is 0x8c.
+13. This density code (0x48) was also used for DAT-160.
 .Ed
 .Sh ENVIRONMENT
 .Bl -tag -width ".Ev TAPE"