[PATCH 4.2.y-ckt 093/268] scsi: add Synology to 1024 sector blacklist

From: Kamal Mostafa
Date: Wed Jan 27 2016 - 16:40:45 EST

4.2.8-ckt3 -stable review patch. If anyone has any objections, please let me know.


From: Mike Christie <mchristi@xxxxxxxxxx>

commit 9055082fb100cc66e20c048251d05159f5f2cfba upstream.

Another iscsi target that cannot handle large IOs, but does not tell us
a limit.

The Synology iSCSI targets report:

Block limits VPD page (SBC):
Write same no zero (WSNZ): 0
Maximum compare and write length: 0 blocks
Optimal transfer length granularity: 0 blocks
Maximum transfer length: 0 blocks
Optimal transfer length: 0 blocks
Maximum prefetch length: 0 blocks
Maximum unmap LBA count: 0
Maximum unmap block descriptor count: 0
Optimal unmap granularity: 0
Unmap granularity alignment valid: 0
Unmap granularity alignment: 0
Maximum write same length: 0x0 blocks

and the size of the command it can handle seems to depend on how much
memory it can allocate at the time. This results in IO errors when
handling large IOs. This patch just has us use the old 1024 default
sectors for this target by adding it to the scsi blacklist. We do not
have good contacs with this vendors, so I have not been able to try and
fix on their side.

I have posted this a long while back, but it was not merged. This
version just fixes it up for merge/patch failures in the original

Reported-by: Ancoron Luciferis <ancoron.luciferis@xxxxxxxxxxxxxx>
Reported-by: Michael Meyers <steltek@xxxxxxxxxx>
Signed-off-by: Mike Christie <mchristi@xxxxxxxxxx>
Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx>
Signed-off-by: Kamal Mostafa <kamal@xxxxxxxxxxxxx>
drivers/scsi/scsi_devinfo.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/drivers/scsi/scsi_devinfo.c b/drivers/scsi/scsi_devinfo.c
index 9f77d23..64ed88a 100644
--- a/drivers/scsi/scsi_devinfo.c
+++ b/drivers/scsi/scsi_devinfo.c
@@ -227,6 +227,7 @@ static struct {
{"Promise", "VTrak E610f", NULL, BLIST_SPARSELUN | BLIST_NO_RSOC},
{"Promise", "", NULL, BLIST_SPARSELUN},
{"QNAP", "iSCSI Storage", NULL, BLIST_MAX_1024},
+ {"SYNOLOGY", "iSCSI Storage", NULL, BLIST_MAX_1024},
{"QUANTUM", "XP34301", "1071", BLIST_NOTQ},
{"SanDisk", "ImageMate CF-SD1", NULL, BLIST_FORCELUN},