3 files changed, 78 insertions, 49 deletions

diff --git a/drivers/target/tcm_fc/tcm_fc.h b/drivers/target/tcm_fc/tcm_fc.h
index f7fff7ed63c3..bd4fe21a23b8 100644
--- a/drivers/target/tcm_fc/tcm_fc.h
+++ b/drivers/target/tcm_fc/tcm_fc.h
@@ -187,4 +187,9 @@ void ft_dump_cmd(struct ft_cmd *, const char *caller);
 
 ssize_t ft_format_wwn(char *, size_t, u64);
 
+/*
+ * Underlying HW specific helper function
+ */
+void ft_invl_hw_context(struct ft_cmd *);
+
 #endif /* __TCM_FC_H__ */
diff --git a/drivers/target/tcm_fc/tfc_cmd.c b/drivers/target/tcm_fc/tfc_cmd.c
index a9e9a31da11d..03977e8996d8 100644
--- a/drivers/target/tcm_fc/tfc_cmd.c
+++ b/drivers/target/tcm_fc/tfc_cmd.c
@@ -320,6 +320,7 @@ static void ft_recv_seq(struct fc_seq *sp, struct fc_frame *fp, void *arg)
         default:
                 pr_debug("%s: unhandled frame r_ctl %x\n",
                        __func__, fh->fh_r_ctl);
+                ft_invl_hw_context(cmd);
                 fc_frame_free(fp);
                 transport_generic_free_cmd(&cmd->se_cmd, 0, 0);
                 break;
diff --git a/drivers/target/tcm_fc/tfc_io.c b/drivers/target/tcm_fc/tfc_io.c
index 11e6483fc127..06943eeb3c84 100644
--- a/drivers/target/tcm_fc/tfc_io.c
+++ b/drivers/target/tcm_fc/tfc_io.c
@@ -214,62 +214,49 @@ void ft_recv_write_data(struct ft_cmd *cmd, struct fc_frame *fp)
         if (!(ntoh24(fh->fh_f_ctl) & FC_FC_REL_OFF))
                 goto drop;
 
+        f_ctl = ntoh24(fh->fh_f_ctl);
+        ep = fc_seq_exch(seq);
+        lport = ep->lp;
+        if (cmd->was_ddp_setup) {
+                BUG_ON(!ep);
+                BUG_ON(!lport);
+        }
+
         /*
-         * Doesn't expect even single byte of payload. Payload
+         * Doesn't expect payload if DDP is setup. Payload
          * is expected to be copied directly to user buffers
-         * due to DDP (Large Rx offload) feature, hence
-         * BUG_ON if BUF is non-NULL
+         * due to DDP (Large Rx offload),
          */
         buf = fc_frame_payload_get(fp, 1);
-        if (cmd->was_ddp_setup && buf) {
-                pr_debug("%s: When DDP was setup, not expected to"
-                                 "receive frame with payload, Payload shall be"
-                                 "copied directly to buffer instead of coming "
-                                 "via. legacy receive queues\n", __func__);
-                BUG_ON(buf);
-        }
+        if (buf)
+                pr_err("%s: xid 0x%x, f_ctl 0x%x, cmd->sg %p, "
+                                "cmd->sg_cnt 0x%x. DDP was setup"
+                                " hence not expected to receive frame with "
+                                "payload, Frame will be dropped if "
+                                "'Sequence Initiative' bit in f_ctl is "
+                                "not set\n", __func__, ep->xid, f_ctl,
+                                cmd->sg, cmd->sg_cnt);
+        /*
+         * Invalidate HW DDP context if it was setup for respective
+         * command. Invalidation of HW DDP context is requited in both
+         * situation (success and error). 
+         */
+        ft_invl_hw_context(cmd);
 
         /*
-         * If ft_cmd indicated 'ddp_setup', in that case only the last frame
-         * should come with 'TSI bit being set'. If 'TSI bit is not set and if
-         * data frame appears here, means error condition. In both the cases
-         * release the DDP context (ddp_put) and in error case, as well
-         * initiate error recovery mechanism.
+         * If "Sequence Initiative (TSI)" bit set in f_ctl, means last
+         * write data frame is received successfully where payload is
+         * posted directly to user buffer and only the last frame's
+         * header is posted in receive queue.
+         *
+         * If "Sequence Initiative (TSI)" bit is not set, means error
+         * condition w.r.t. DDP, hence drop the packet and let explict
+         * ABORTS from other end of exchange timer trigger the recovery.
          */
-        ep = fc_seq_exch(seq);
-        if (cmd->was_ddp_setup) {
-                BUG_ON(!ep);
-                lport = ep->lp;
-                BUG_ON(!lport);
-        }
-        if (cmd->was_ddp_setup && ep->xid != FC_XID_UNKNOWN) {
-                f_ctl = ntoh24(fh->fh_f_ctl);
-                /*
-                 * If TSI bit set in f_ctl, means last write data frame is
-                 * received successfully where payload is posted directly
-                 * to user buffer and only the last frame's header is posted
-                 * in legacy receive queue
-                 */
-                if (f_ctl & FC_FC_SEQ_INIT) { /* TSI bit set in FC frame */
-                        cmd->write_data_len = lport->tt.ddp_done(lport,
-                                                                ep->xid);
-                        goto last_frame;
-                } else {
-                        /*
-                         * Updating the write_data_len may be meaningless at
-                         * this point, but just in case if required in future
-                         * for debugging or any other purpose
-                         */
-                        pr_err("%s: Received frame with TSI bit not"
-                                        " being SET, dropping the frame, "
-                                        "cmd->sg <%p>, cmd->sg_cnt <0x%x>\n",
-                                        __func__, cmd->sg, cmd->sg_cnt);
-                        cmd->write_data_len = lport->tt.ddp_done(lport,
-                                                              ep->xid);
-                        lport->tt.seq_exch_abort(cmd->seq, 0);
-                        goto drop;
-                }
-        }
+        if (f_ctl & FC_FC_SEQ_INIT)
+                goto last_frame;
+        else
+                goto drop;
 
         rel_off = ntohl(fh->fh_parm_offset);
         frame_len = fr_len(fp);
@@ -332,3 +319,39 @@ last_frame:
 drop:
         fc_frame_free(fp);
 }
+
+/*
+ * Handle and cleanup any HW specific resources if
+ * received ABORTS, errors, timeouts.
+ */
+void ft_invl_hw_context(struct ft_cmd *cmd)
+{
+        struct fc_seq *seq = cmd->seq;
+        struct fc_exch *ep = NULL;
+        struct fc_lport *lport = NULL;
+
+        BUG_ON(!cmd);
+
+        /* Cleanup the DDP context in HW if DDP was setup */
+        if (cmd->was_ddp_setup && seq) {
+                ep = fc_seq_exch(seq);
+                if (ep) {
+                        lport = ep->lp;
+                        if (lport && (ep->xid <= lport->lro_xid))
+                                /*
+                                 * "ddp_done" trigger invalidation of HW
+                                 * specific DDP context
+                                 */
+                                cmd->write_data_len = lport->tt.ddp_done(lport,
+                                                                      ep->xid);
+
+                                /*
+                                 * Resetting same variable to indicate HW's
+                                 * DDP context has been invalidated to avoid
+                                 * re_invalidation of same context (context is
+                                 * identified using ep->xid)
+                                 */
+                                cmd->was_ddp_setup = 0;
+                }
+        }
+}