1 files changed, 49 insertions, 15 deletions

diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c
index 4558f2e1fe1b..f0e8f0f4ccb4 100644
--- a/drivers/target/target_core_transport.c
+++ b/drivers/target/target_core_transport.c
@@ -779,7 +779,9 @@ EXPORT_SYMBOL(target_complete_cmd);
 
 void target_complete_cmd_with_length(struct se_cmd *cmd, u8 scsi_status, int length)
 {
-	if (scsi_status == SAM_STAT_GOOD && length < cmd->data_length) {
+	if ((scsi_status == SAM_STAT_GOOD ||
+	     cmd->se_cmd_flags & SCF_TREAT_READ_AS_NORMAL) &&
+	    length < cmd->data_length) {
 		if (cmd->se_cmd_flags & SCF_UNDERFLOW_BIT) {
 			cmd->residual_count += cmd->data_length - length;
 		} else {
@@ -1431,7 +1433,7 @@ transport_generic_map_mem_to_cmd(struct se_cmd *cmd, struct scatterlist *sgl,
 	return 0;
 }
 
-/*
+/**
  * target_submit_cmd_map_sgls - lookup unpacked lun and submit uninitialized
  * 			 se_cmd + use pre-allocated SGL memory.
  *
@@ -1441,7 +1443,7 @@ transport_generic_map_mem_to_cmd(struct se_cmd *cmd, struct scatterlist *sgl,
  * @sense: pointer to SCSI sense buffer
  * @unpacked_lun: unpacked LUN to reference for struct se_lun
  * @data_length: fabric expected data transfer length
- * @task_addr: SAM task attribute
+ * @task_attr: SAM task attribute
  * @data_dir: DMA data direction
  * @flags: flags for command submission from target_sc_flags_tables
  * @sgl: struct scatterlist memory for unidirectional mapping
@@ -1578,7 +1580,7 @@ int target_submit_cmd_map_sgls(struct se_cmd *se_cmd, struct se_session *se_sess
 }
 EXPORT_SYMBOL(target_submit_cmd_map_sgls);
 
-/*
+/**
  * target_submit_cmd - lookup unpacked lun and submit uninitialized se_cmd
  *
  * @se_cmd: command descriptor to submit
@@ -1587,7 +1589,7 @@ EXPORT_SYMBOL(target_submit_cmd_map_sgls);
  * @sense: pointer to SCSI sense buffer
  * @unpacked_lun: unpacked LUN to reference for struct se_lun
  * @data_length: fabric expected data transfer length
- * @task_addr: SAM task attribute
+ * @task_attr: SAM task attribute
  * @data_dir: DMA data direction
  * @flags: flags for command submission from target_sc_flags_tables
  *
@@ -1654,7 +1656,7 @@ static bool target_lookup_lun_from_tag(struct se_session *se_sess, u64 tag,
  * @se_sess: associated se_sess for endpoint
  * @sense: pointer to SCSI sense buffer
  * @unpacked_lun: unpacked LUN to reference for struct se_lun
- * @fabric_context: fabric context for TMR req
+ * @fabric_tmr_ptr: fabric context for TMR req
  * @tm_type: Type of TM request
  * @gfp: gfp type for caller
  * @tag: referenced task tag for TMR_ABORT_TASK
@@ -2084,12 +2086,24 @@ static void transport_complete_qf(struct se_cmd *cmd)
 		goto queue_status;
 	}
 
-	if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE)
+	/*
+	 * Check if we need to send a sense buffer from
+	 * the struct se_cmd in question. We do NOT want
+	 * to take this path of the IO has been marked as
+	 * needing to be treated like a "normal read". This
+	 * is the case if it's a tape read, and either the
+	 * FM, EOM, or ILI bits are set, but there is no
+	 * sense data.
+	 */
+	if (!(cmd->se_cmd_flags & SCF_TREAT_READ_AS_NORMAL) &&
+	    cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE)
 		goto queue_status;
 
 	switch (cmd->data_direction) {
 	case DMA_FROM_DEVICE:
-		if (cmd->scsi_status)
+		/* queue status if not treating this as a normal read */
+		if (cmd->scsi_status &&
+		    !(cmd->se_cmd_flags & SCF_TREAT_READ_AS_NORMAL))
 			goto queue_status;
 
 		trace_target_cmd_complete(cmd);
@@ -2194,9 +2208,15 @@ static void target_complete_ok_work(struct work_struct *work)
 
 	/*
 	 * Check if we need to send a sense buffer from
-	 * the struct se_cmd in question.
+	 * the struct se_cmd in question. We do NOT want
+	 * to take this path of the IO has been marked as
+	 * needing to be treated like a "normal read". This
+	 * is the case if it's a tape read, and either the
+	 * FM, EOM, or ILI bits are set, but there is no
+	 * sense data.
 	 */
-	if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
+	if (!(cmd->se_cmd_flags & SCF_TREAT_READ_AS_NORMAL) &&
+	    cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
 		WARN_ON(!cmd->scsi_status);
 		ret = transport_send_check_condition_and_sense(
 					cmd, 0, 1);
@@ -2238,7 +2258,18 @@ static void target_complete_ok_work(struct work_struct *work)
 queue_rsp:
 	switch (cmd->data_direction) {
 	case DMA_FROM_DEVICE:
-		if (cmd->scsi_status)
+		/*
+		 * if this is a READ-type IO, but SCSI status
+		 * is set, then skip returning data and just
+		 * return the status -- unless this IO is marked
+		 * as needing to be treated as a normal read,
+		 * in which case we want to go ahead and return
+		 * the data. This happens, for example, for tape
+		 * reads with the FM, EOM, or ILI bits set, with
+		 * no sense data.
+		 */
+		if (cmd->scsi_status &&
+		    !(cmd->se_cmd_flags & SCF_TREAT_READ_AS_NORMAL))
 			goto queue_status;
 
 		atomic_long_add(cmd->data_length,
@@ -2606,7 +2637,8 @@ int transport_generic_free_cmd(struct se_cmd *cmd, int wait_for_tasks)
 }
 EXPORT_SYMBOL(transport_generic_free_cmd);
 
-/* target_get_sess_cmd - Add command to active ->sess_cmd_list
+/**
+ * target_get_sess_cmd - Add command to active ->sess_cmd_list
  * @se_cmd:	command descriptor to add
  * @ack_kref:	Signal that fabric will perform an ack target_put_sess_cmd()
  */
@@ -2800,7 +2832,8 @@ void target_show_cmd(const char *pfx, struct se_cmd *cmd)
 }
 EXPORT_SYMBOL(target_show_cmd);
 
-/* target_sess_cmd_list_set_waiting - Flag all commands in
+/**
+ * target_sess_cmd_list_set_waiting - Flag all commands in
  *         sess_cmd_list to complete cmd_wait_comp.  Set
  *         sess_tearing_down so no more commands are queued.
  * @se_sess:	session to flag
@@ -2835,7 +2868,8 @@ void target_sess_cmd_list_set_waiting(struct se_session *se_sess)
 }
 EXPORT_SYMBOL(target_sess_cmd_list_set_waiting);
 
-/* target_wait_for_sess_cmds - Wait for outstanding descriptors
+/**
+ * target_wait_for_sess_cmds - Wait for outstanding descriptors
  * @se_sess:    session to wait for active I/O
  */
 void target_wait_for_sess_cmds(struct se_session *se_sess)
@@ -3332,7 +3366,7 @@ static void target_tmr_work(struct work_struct *work)
 		tmr->response = TMR_FUNCTION_REJECTED;
 		break;
 	default:
-		pr_err("Uknown TMR function: 0x%02x.\n",
+		pr_err("Unknown TMR function: 0x%02x.\n",
 				tmr->function);
 		tmr->response = TMR_FUNCTION_REJECTED;
 		break;