Merge git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending

Pull SCSI target fixes from Nicholas Bellinger:

 "There has been work in a number of different areas over the last
  weeks, including:

   - Fix target-core-user (TCMU) back-end bi-directional handling (Xiubo
     Li + Mike Christie + Ilias Tsitsimpis)

   - Fix iscsi-target TMR reference leak during session shutdown (Rob
     Millner + Chu Yuan Lin)

   - Fix target_core_fabric_configfs.c race between LUN shutdown +
     mapped LUN creation (James Shen)

   - Fix target-core unknown fabric callback queue-full errors (Potnuri
     Bharat Teja)

   - Fix iscsi-target + iser-target queue-full handling in order to
     support iw_cxgb4 RNICs. (Potnuri Bharat Teja + Sagi Grimberg)

   - Fix ALUA transition state race between multiple initiator (Mike
     Christie)

   - Drop work-around for legacy GlobalSAN initiator, to allow QLogic
     57840S + 579xx offload HBAs to work out-of-the-box in MSFT
     environments. (Martin Svec + Arun Easi)

  Note that a number are CC'ed for stable, and although the queue-full
  bug-fixes required for iser-target to work with iw_cxgb4 aren't CC'ed
  here, they'll be posted to Greg-KH separately"

* git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending:
  tcmu: Skip Data-Out blocks before gathering Data-In buffer for BIDI case
  iscsi-target: Drop work-around for legacy GlobalSAN initiator
  target: Fix ALUA transition state race between multiple initiators
  iser-target: avoid posting a recv buffer twice
  iser-target: Fix queue-full response handling
  iscsi-target: Propigate queue_data_in + queue_status errors
  target: Fix unknown fabric callback queue-full errors
  tcmu: Fix wrongly calculating of the base_command_size
  tcmu: Fix possible overwrite of t_data_sg's last iov[]
  target: Avoid mappedlun symlink creation during lun shutdown
  iscsi-target: Fix TMR reference leak during session shutdown
  usb: gadget: Correct usb EP argument for BOT status request
  tcmu: Allow cmd_time_out to be set to zero (disabled)

2 files changed, 49 insertions, 19 deletions

diff --git a/drivers/infiniband/ulp/isert/ib_isert.c b/drivers/infiniband/ulp/isert/ib_isert.c
index 91cbe86b25c8..fcbed35e95a8 100644
--- a/drivers/infiniband/ulp/isert/ib_isert.c
+++ b/drivers/infiniband/ulp/isert/ib_isert.c
@@ -817,6 +817,7 @@ isert_post_recvm(struct isert_conn *isert_conn, u32 count)
 		rx_wr->sg_list = &rx_desc->rx_sg;
 		rx_wr->num_sge = 1;
 		rx_wr->next = rx_wr + 1;
+		rx_desc->in_use = false;
 	}
 	rx_wr--;
 	rx_wr->next = NULL; /* mark end of work requests list */
@@ -835,6 +836,15 @@ isert_post_recv(struct isert_conn *isert_conn, struct iser_rx_desc *rx_desc)
 	struct ib_recv_wr *rx_wr_failed, rx_wr;
 	int ret;
 
+	if (!rx_desc->in_use) {
+		/*
+		 * if the descriptor is not in-use we already reposted it
+		 * for recv, so just silently return
+		 */
+		return 0;
+	}
+
+	rx_desc->in_use = false;
 	rx_wr.wr_cqe = &rx_desc->rx_cqe;
 	rx_wr.sg_list = &rx_desc->rx_sg;
 	rx_wr.num_sge = 1;
@@ -1397,6 +1407,8 @@ isert_recv_done(struct ib_cq *cq, struct ib_wc *wc)
 		return;
 	}
 
+	rx_desc->in_use = true;
+
 	ib_dma_sync_single_for_cpu(ib_dev, rx_desc->dma_addr,
 			ISER_RX_PAYLOAD_SIZE, DMA_FROM_DEVICE);
 
@@ -1659,10 +1671,23 @@ isert_rdma_write_done(struct ib_cq *cq, struct ib_wc *wc)
 	ret = isert_check_pi_status(cmd, isert_cmd->rw.sig->sig_mr);
 	isert_rdma_rw_ctx_destroy(isert_cmd, isert_conn);
 
-	if (ret)
-		transport_send_check_condition_and_sense(cmd, cmd->pi_err, 0);
-	else
-		isert_put_response(isert_conn->conn, isert_cmd->iscsi_cmd);
+	if (ret) {
+		/*
+		 * transport_generic_request_failure() expects to have
+		 * plus two references to handle queue-full, so re-add
+		 * one here as target-core will have already dropped
+		 * it after the first isert_put_datain() callback.
+		 */
+		kref_get(&cmd->cmd_kref);
+		transport_generic_request_failure(cmd, cmd->pi_err);
+	} else {
+		/*
+		 * XXX: isert_put_response() failure is not retried.
+		 */
+		ret = isert_put_response(isert_conn->conn, isert_cmd->iscsi_cmd);
+		if (ret)
+			pr_warn_ratelimited("isert_put_response() ret: %d\n", ret);
+	}
 }
 
 static void
@@ -1699,13 +1724,15 @@ isert_rdma_read_done(struct ib_cq *cq, struct ib_wc *wc)
 	cmd->i_state = ISTATE_RECEIVED_LAST_DATAOUT;
 	spin_unlock_bh(&cmd->istate_lock);
 
-	if (ret) {
-		target_put_sess_cmd(se_cmd);
-		transport_send_check_condition_and_sense(se_cmd,
-							 se_cmd->pi_err, 0);
-	} else {
+	/*
+	 * transport_generic_request_failure() will drop the extra
+	 * se_cmd->cmd_kref reference after T10-PI error, and handle
+	 * any non-zero ->queue_status() callback error retries.
+	 */
+	if (ret)
+		transport_generic_request_failure(se_cmd, se_cmd->pi_err);
+	else
 		target_execute_cmd(se_cmd);
-	}
 }
 
 static void
@@ -2171,26 +2198,28 @@ isert_put_datain(struct iscsi_conn *conn, struct iscsi_cmd *cmd)
 		chain_wr = &isert_cmd->tx_desc.send_wr;
 	}
 
-	isert_rdma_rw_ctx_post(isert_cmd, isert_conn, cqe, chain_wr);
-	isert_dbg("Cmd: %p posted RDMA_WRITE for iSER Data READ\n", isert_cmd);
-	return 1;
+	rc = isert_rdma_rw_ctx_post(isert_cmd, isert_conn, cqe, chain_wr);
+	isert_dbg("Cmd: %p posted RDMA_WRITE for iSER Data READ rc: %d\n",
+		  isert_cmd, rc);
+	return rc;
 }
 
 static int
 isert_get_dataout(struct iscsi_conn *conn, struct iscsi_cmd *cmd, bool recovery)
 {
 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
+	int ret;
 
 	isert_dbg("Cmd: %p RDMA_READ data_length: %u write_data_done: %u\n",
 		 isert_cmd, cmd->se_cmd.data_length, cmd->write_data_done);
 
 	isert_cmd->tx_desc.tx_cqe.done = isert_rdma_read_done;
-	isert_rdma_rw_ctx_post(isert_cmd, conn->context,
-			&isert_cmd->tx_desc.tx_cqe, NULL);
+	ret = isert_rdma_rw_ctx_post(isert_cmd, conn->context,
+				     &isert_cmd->tx_desc.tx_cqe, NULL);
 
-	isert_dbg("Cmd: %p posted RDMA_READ memory for ISER Data WRITE\n",
-		 isert_cmd);
-	return 0;
+	isert_dbg("Cmd: %p posted RDMA_READ memory for ISER Data WRITE rc: %d\n",
+		 isert_cmd, ret);
+	return ret;
 }
 
 static int
diff --git a/drivers/infiniband/ulp/isert/ib_isert.h b/drivers/infiniband/ulp/isert/ib_isert.h
index c02ada57d7f5..87d994de8c91 100644
--- a/drivers/infiniband/ulp/isert/ib_isert.h
+++ b/drivers/infiniband/ulp/isert/ib_isert.h
@@ -60,7 +60,7 @@
 
 #define ISER_RX_PAD_SIZE	(ISCSI_DEF_MAX_RECV_SEG_LEN + 4096 - \
 		(ISER_RX_PAYLOAD_SIZE + sizeof(u64) + sizeof(struct ib_sge) + \
-		 sizeof(struct ib_cqe)))
+		 sizeof(struct ib_cqe) + sizeof(bool)))
 
 #define ISCSI_ISER_SG_TABLESIZE		256
 
@@ -85,6 +85,7 @@ struct iser_rx_desc {
 	u64		dma_addr;
 	struct ib_sge	rx_sg;
 	struct ib_cqe	rx_cqe;
+	bool		in_use;
 	char		pad[ISER_RX_PAD_SIZE];
 } __packed;