diff mbox

[v2,11/36] target: Make it possible to specify I_T nexus for SCSI abort

Message ID 20170202005853.23456-12-bart.vanassche@sandisk.com (mailing list archive)
State Superseded
Headers show

Commit Message

Bart Van Assche Feb. 2, 2017, 12:58 a.m. UTC 
target_submit_tmr() only supports the I_T_L nexus for SCSI abort
and other task management functions. Make it possible for target
drivers to specify I_T nexus for SCSI abort by passing the
TARGET_SCF_IGNORE_TMR_LUN flag to target_submit_tmr().

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Himanshu Madhani <himanshu.madhani@cavium.com>
Cc: Giridhar Malavali <giridhar.malavali@cavium.com>
---
 drivers/target/target_core_tmr.c       | 16 +++++++++++++++-
 drivers/target/target_core_transport.c | 30 +++++++++++++++++++++++-------
 include/target/target_core_base.h      |  1 +
 3 files changed, 39 insertions(+), 8 deletions(-)

Comments

Christoph Hellwig Feb. 6, 2017, 9:09 a.m. UTC | #1 
Looks fine,

Reviewed-by: Christoph Hellwig <hch@lst.de>
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diff mbox

Patch

diff --git a/drivers/target/target_core_tmr.c b/drivers/target/target_core_tmr.c
index 311dc3c2f1dc..367799b4dde1 100644
--- a/drivers/target/target_core_tmr.c
+++ b/drivers/target/target_core_tmr.c
@@ -149,6 +149,13 @@  static bool __target_check_io_state(struct se_cmd *se_cmd,
 	return kref_get_unless_zero(&se_cmd->cmd_kref);
 }
 
+/**
+ * core_tmr_abort_task - abort a SCSI command
+ * @dev: LUN specified in task management function or NULL if no LUN has been
+ *	 specified.
+ * @tmr: Task management function.
+ * @se_sess: Session a.k.a. I_T nexus.
+ */
 void core_tmr_abort_task(
 	struct se_device *dev,
 	struct se_tmr_req *tmr,
@@ -161,7 +168,7 @@  void core_tmr_abort_task(
 	spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
 	list_for_each_entry(se_cmd, &se_sess->sess_cmd_list, se_cmd_list) {
 
-		if (dev != se_cmd->se_dev)
+		if (dev && dev != se_cmd->se_dev)
 			continue;
 
 		/* skip task management functions, including tmr->task_cmd */
@@ -178,6 +185,13 @@  void core_tmr_abort_task(
 		if (!__target_check_io_state(se_cmd, se_sess, 0))
 			continue;
 
+		if (!tmr->tmr_dev &&
+		    transport_lookup_tmr_lun(tmr->task_cmd,
+					     se_cmd->orig_fe_lun) < 0) {
+			target_put_sess_cmd(se_cmd);
+			continue;
+		}
+
 		list_del_init(&se_cmd->se_cmd_list);
 		spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
 
diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c
index 18a76ee641ea..3f54ec6d7f66 100644
--- a/drivers/target/target_core_transport.c
+++ b/drivers/target/target_core_transport.c
@@ -1598,18 +1598,18 @@  static void target_complete_tmr_failure(struct work_struct *work)
 }
 
 /**
- * target_submit_tmr - lookup unpacked lun and submit uninitialized se_cmd
- *                     for TMR CDBs
+ * target_submit_tmr - submit a SCSI task management function to the target core
  *
  * @se_cmd: command descriptor to submit
  * @se_sess: associated se_sess for endpoint
  * @sense: pointer to SCSI sense buffer
- * @unpacked_lun: unpacked LUN to reference for struct se_lun
+ * @unpacked_lun: LUN the TMR applies to. Ignored if TARGET_SCF_IGNORE_TMR_LUN
+ *	has been set in @flags.
  * @fabric_context: fabric context for TMR req
  * @tm_type: Type of TM request
  * @gfp: gfp type for caller
  * @tag: referenced task tag for TMR_ABORT_TASK
- * @flags: submit cmd flags
+ * @flags: submit cmd flags (TARGET_SCF_*).
  *
  * Callable from all contexts.
  **/
@@ -1645,7 +1645,14 @@  int target_submit_tmr(struct se_cmd *se_cmd, struct se_session *se_sess,
 		return ret;
 	}
 
-	ret = transport_lookup_tmr_lun(se_cmd, unpacked_lun);
+	if (flags & TARGET_SCF_IGNORE_TMR_LUN) {
+		WARN_ON_ONCE(tm_type != TMR_ABORT_TASK);
+		se_cmd->se_lun = NULL;
+		se_cmd->se_dev = NULL;
+		se_cmd->se_tmr_req->tmr_dev = NULL;
+	} else {
+		ret = transport_lookup_tmr_lun(se_cmd, unpacked_lun);
+	}
 	if (ret) {
 		/*
 		 * For callback during failure handling, push this work off
@@ -1655,6 +1662,7 @@  int target_submit_tmr(struct se_cmd *se_cmd, struct se_session *se_sess,
 		schedule_work(&se_cmd->work);
 		return 0;
 	}
+	WARN_ON_ONCE(tm_type != TMR_ABORT_TASK && !se_cmd->se_dev);
 	transport_generic_handle_tmr(se_cmd);
 	return 0;
 }
@@ -3133,8 +3141,16 @@  static void target_tmr_work(struct work_struct *work)
 	transport_cmd_check_stop_to_fabric(cmd);
 }
 
-int transport_generic_handle_tmr(
-	struct se_cmd *cmd)
+/**
+ * transport_generic_handle_tmr - queue a task management function
+ *
+ * Note: task management functions for which flag TARGET_SCF_IGNORE_TMR_LUN
+ * has been set are queued on a separate workqueue. This may cause out-of-order
+ * execution of task management functions. That is fine though since the
+ * SCSI Architecture Manual does not require that task management functions
+ * are executed in order.
+ */
+int transport_generic_handle_tmr(struct se_cmd *cmd)
 {
 	unsigned long flags;
 
diff --git a/include/target/target_core_base.h b/include/target/target_core_base.h
index 5cb7583ad701..fb87f0e5d0d6 100644
--- a/include/target/target_core_base.h
+++ b/include/target/target_core_base.h
@@ -186,6 +186,7 @@  enum target_sc_flags_table {
 	TARGET_SCF_ACK_KREF		= 0x02,
 	TARGET_SCF_UNKNOWN_SIZE		= 0x04,
 	TARGET_SCF_USE_CPUID	= 0x08,
+	TARGET_SCF_IGNORE_TMR_LUN	= 0x10,
 };
 
 /* fabric independent task management function values */