From 935dc8d7575e6c1292b057e39045a40f1fbe26e7 Mon Sep 17 00:00:00 2001
From: Mike Miller <mike.miller@hp.com>
Date: Mon, 4 Aug 2008 11:54:54 +0200
Subject: [PATCH] cciss: add support for multi lun tape devices
This patch adds support for multi-lun devices in a SAS environment. It's
required for the support of media changers.
Signed-off-by: Stephen M. Cameron <scameron@beardog.cca.cpqcorp.net>
Signed-off-by: Mike Miller <mike.miller@hp.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
---
drivers/block/cciss_scsi.c | 40 +++++++++++++++++++++++++++++++++++---
1 file changed, 37 insertions(+), 3 deletions(-)
diff --git a/drivers/block/cciss_scsi.c b/drivers/block/cciss_scsi.c
index c673ff14126a..e1233aabda77 100644
--- a/drivers/block/cciss_scsi.c
+++ b/drivers/block/cciss_scsi.c
@@ -371,16 +371,50 @@ cciss_scsi_add_entry(int ctlr, int hostno,
/* assumes hba[ctlr]->scsi_ctlr->lock is held */
int n = ccissscsi[ctlr].ndevices;
struct cciss_scsi_dev_t *sd;
+ int i, bus, target, lun;
+ unsigned char addr1[8], addr2[8];
if (n >= CCISS_MAX_SCSI_DEVS_PER_HBA) {
printk("cciss%d: Too many devices, "
"some will be inaccessible.\n", ctlr);
return -1;
}
- sd = &ccissscsi[ctlr].dev[n];
- if (find_bus_target_lun(ctlr, &sd->bus, &sd->target, &sd->lun) != 0)
- return -1;
+ bus = target = -1;
+ lun = 0;
+ /* Is this device a non-zero lun of a multi-lun device */
+ /* byte 4 of the 8-byte LUN addr will contain the logical unit no. */
+ if (scsi3addr[4] != 0) {
+ /* Search through our list and find the device which */
+ /* has the same 8 byte LUN address, excepting byte 4. */
+ /* Assign the same bus and target for this new LUN. */
+ /* Use the logical unit number from the firmware. */
+ memcpy(addr1, scsi3addr, 8);
+ addr1[4] = 0;
+ for (i = 0; i < n; i++) {
+ sd = &ccissscsi[ctlr].dev[i];
+ memcpy(addr2, sd->scsi3addr, 8);
+ addr2[4] = 0;
+ /* differ only in byte 4? */
+ if (memcmp(addr1, addr2, 8) == 0) {
+ bus = sd->bus;
+ target = sd->target;
+ lun = scsi3addr[4];
+ break;
+ }
+ }
+ }
+
+ sd = &ccissscsi[ctlr].dev[n];
+ if (lun == 0) {
+ if (find_bus_target_lun(ctlr,
+ &sd->bus, &sd->target, &sd->lun) != 0)
+ return -1;
+ } else {
+ sd->bus = bus;
+ sd->target = target;
+ sd->lun = lun;
+ }
added[*nadded].bus = sd->bus;
added[*nadded].target = sd->target;
added[*nadded].lun = sd->lun;
--
2.34.1