[SRU][Xenial][PATCH 2/4] ses: fix discovery of SATA devices in SAS enclosures

[Joseph Salisbury]

From: James Bottomley <James.Bottomley at HansenPartnership.com>

BugLink: http://bugs.launchpad.net/bugs/1693369

The current discovery routines use the VPD 0x83 inquiry page to find
the device SAS address and match it to the end point in the enclosure.
This doesn't work for SATA devices because expanders (or hosts) simply
make up an endpoint address for STP and thus the address returned by
the VPD page never matches.  Instead of doing this, for SAS attached
devices, match by the direct endpoint address instead.

Signed-off-by: James Bottomley <James.Bottomley at HansenPartnership.com>
(cherry picked from commit 3f8d6f2a0797e8c650a47e5c1b5c2601a46f4293)
Signed-off-by: Joseph Salisbury <joseph.salisbury at canonical.com>
---
 drivers/scsi/Kconfig |  1 +
 drivers/scsi/ses.c   | 22 ++++------------------
 2 files changed, 5 insertions(+), 18 deletions(-)

diff --git a/drivers/scsi/Kconfig b/drivers/scsi/Kconfig
index eec02a6..910809f 100644
--- a/drivers/scsi/Kconfig
+++ b/drivers/scsi/Kconfig
@@ -194,6 +194,7 @@ config CHR_DEV_SCH
 config SCSI_ENCLOSURE
 	tristate "SCSI Enclosure Support"
 	depends on SCSI && ENCLOSURE_SERVICES
+	depends on m || SCSI_SAS_ATTRS != m
 	help
 	  Enclosures are devices sitting on or in SCSI backplanes that
 	  manage devices.  If you have a disk cage, the chances are that
diff --git a/drivers/scsi/ses.c b/drivers/scsi/ses.c
index 01168ac..e10d87f 100644
--- a/drivers/scsi/ses.c
+++ b/drivers/scsi/ses.c
@@ -34,6 +34,8 @@
 #include <scsi/scsi_driver.h>
 #include <scsi/scsi_host.h>
 
+#include <scsi/scsi_transport_sas.h>
+
 struct ses_device {
 	unsigned char *page1;
 	unsigned char *page1_types;
@@ -578,31 +580,15 @@ static void ses_enclosure_data_process(struct enclosure_device *edev,
 static void ses_match_to_enclosure(struct enclosure_device *edev,
 				   struct scsi_device *sdev)
 {
-	unsigned char *desc;
 	struct efd efd = {
 		.addr = 0,
 	};
 
 	ses_enclosure_data_process(edev, to_scsi_device(edev->edev.parent), 0);
 
-	if (!sdev->vpd_pg83_len)
-		return;
-
-	desc = sdev->vpd_pg83 + 4;
-	while (desc < sdev->vpd_pg83 + sdev->vpd_pg83_len) {
-		enum scsi_protocol proto = desc[0] >> 4;
-		u8 code_set = desc[0] & 0x0f;
-		u8 piv = desc[1] & 0x80;
-		u8 assoc = (desc[1] & 0x30) >> 4;
-		u8 type = desc[1] & 0x0f;
-		u8 len = desc[3];
-
-		if (piv && code_set == 1 && assoc == 1
-		    && proto == SCSI_PROTOCOL_SAS && type == 3 && len == 8)
-			efd.addr = get_unaligned_be64(&desc[4]);
+	if (is_sas_attached(sdev))
+		efd.addr = sas_get_address(sdev);
 
-		desc += len + 4;
-	}
 	if (efd.addr) {
 		efd.dev = &sdev->sdev_gendev;
 
-- 
2.7.4