[PATCH AUTOSEL 4.9 11/91] IB/iser: bound protection_sg size by data_sg size

From: Sasha Levin
Date: Tue Dec 10 2019 - 17:30:55 EST


From: Max Gurtovoy <maxg@xxxxxxxxxxxx>

[ Upstream commit 7718cf03c3ce4b6ebd90107643ccd01c952a1fce ]

In case we don't set the sg_prot_tablesize, the scsi layer assign the
default size (65535 entries). We should limit this size since we should
take into consideration the underlaying device capability. This cap is
considered when calculating the sg_tablesize. Otherwise, for example,
we can get that /sys/block/sdb/queue/max_segments is 128 and
/sys/block/sdb/queue/max_integrity_segments is 65535.

Link: https://lore.kernel.org/r/1569359027-10987-1-git-send-email-maxg@xxxxxxxxxxxx
Signed-off-by: Max Gurtovoy <maxg@xxxxxxxxxxxx>
Reviewed-by: Sagi Grimberg <sagi@xxxxxxxxxxx>
Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/infiniband/ulp/iser/iscsi_iser.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/drivers/infiniband/ulp/iser/iscsi_iser.c b/drivers/infiniband/ulp/iser/iscsi_iser.c
index e46e2b095c184..fdf5179a81c10 100644
--- a/drivers/infiniband/ulp/iser/iscsi_iser.c
+++ b/drivers/infiniband/ulp/iser/iscsi_iser.c
@@ -649,6 +649,7 @@ iscsi_iser_session_create(struct iscsi_endpoint *ep,
if (ib_conn->pi_support) {
u32 sig_caps = ib_conn->device->ib_device->attrs.sig_prot_cap;

+ shost->sg_prot_tablesize = shost->sg_tablesize;
scsi_host_set_prot(shost, iser_dif_prot_caps(sig_caps));
scsi_host_set_guard(shost, SHOST_DIX_GUARD_IP |
SHOST_DIX_GUARD_CRC);
--
2.20.1