iscsi,iser-target: Expose supported protection ops according to t10_pi

iSER will report supported protection operations based on
the tpg attribute t10_pi settings and HCA PI offload capabilities.
If the HCA does not support PI offload or tpg attribute t10_pi is
not set, we fall to SW PI mode.

In order to do that, we move iscsit_get_sup_prot_ops after connection
tpg assignment.

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Cc: <stable@vger.kernel.org> # v3.14+
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

2 files changed, 12 insertions, 3 deletions

diff --git a/drivers/infiniband/ulp/isert/ib_isert.c b/drivers/infiniband/ulp/isert/ib_isert.c
index 618c81576b05..a6daabc70425 100644
--- a/drivers/infiniband/ulp/isert/ib_isert.c
+++ b/drivers/infiniband/ulp/isert/ib_isert.c
@@ -64,7 +64,7 @@ struct rdma_cm_id *isert_setup_id(struct isert_np *isert_np);
 static inline bool
 isert_prot_cmd(struct isert_conn *conn, struct se_cmd *cmd)
 {
-        return (conn->conn_device->pi_capable &&
+        return (conn->pi_support &&
                 cmd->prot_op != TARGET_PROT_NORMAL);
 }
 
@@ -2324,8 +2324,16 @@ isert_get_sup_prot_ops(struct iscsi_conn *conn)
         struct isert_conn *isert_conn = (struct isert_conn *)conn->context;
         struct isert_device *device = isert_conn->conn_device;
 
-        if (device->pi_capable)
-                return TARGET_PROT_ALL;
+        if (conn->tpg->tpg_attrib.t10_pi) {
+                if (device->pi_capable) {
+                        pr_info("conn %p PI offload enabled\n", isert_conn);
+                        isert_conn->pi_support = true;
+                        return TARGET_PROT_ALL;
+                }
+        }
+
+        pr_info("conn %p PI offload disabled\n", isert_conn);
+        isert_conn->pi_support = false;
 
         return TARGET_PROT_NORMAL;
 }
diff --git a/drivers/infiniband/ulp/isert/ib_isert.h b/drivers/infiniband/ulp/isert/ib_isert.h
index 2e7868c5ad14..141905f446dd 100644
--- a/drivers/infiniband/ulp/isert/ib_isert.h
+++ b/drivers/infiniband/ulp/isert/ib_isert.h
@@ -128,6 +128,7 @@ struct isert_conn {
         atomic_t                post_send_buf_count;
         u32                     responder_resources;
         u32                     initiator_depth;
+        bool                    pi_support;
         u32                     max_sge;
         char                    *login_buf;
         char                    *login_req_buf;