diff mbox series

[12/16] qla2xxx: Fix premature command free

Message ID 20180911171827.29016-13-himanshu.madhani@cavium.com (mailing list archive)
State Accepted
Headers show
Series qla2xxx: Driver updates for scsi-misc | expand

Commit Message

Madhani, Himanshu Sept. 11, 2018, 5:18 p.m. UTC 
From: Quinn Tran <quinn.tran@cavium.com>

When qla2xxx and Target Core gets out of sync, during
command cleanup, qla2xxx will not free command until
it is out of firmware's hand and Target Core has called
the release on the command.

This patch adds synchronization using cmd_lock and release flag.
if the release flag is set then qla2xxx will free up the command
using qlt_free_cmd() otherwise transport_generic_free_cmd() will
be responsible for relase of the command.

Signed-off-by: Quinn Tran <quinn.tran@cavium.com>
Signed-off-by: Himanshu Madhani <himanshu.madhani@cavium.com>
---
 drivers/scsi/qla2xxx/qla_target.c  |  4 ++++
 drivers/scsi/qla2xxx/qla_target.h  |  1 +
 drivers/scsi/qla2xxx/tcm_qla2xxx.c | 45 +++++++++++++++++++++++++++++++++++---
 3 files changed, 47 insertions(+), 3 deletions(-)
diff mbox series

Patch

diff --git a/drivers/scsi/qla2xxx/qla_target.c b/drivers/scsi/qla2xxx/qla_target.c
index 666146a86d10..a69ec4519d81 100644
--- a/drivers/scsi/qla2xxx/qla_target.c
+++ b/drivers/scsi/qla2xxx/qla_target.c
@@ -3383,7 +3383,9 @@  int qlt_xmit_response(struct qla_tgt_cmd *cmd, int xmit_type,
 
 
 	cmd->state = QLA_TGT_STATE_PROCESSED; /* Mid-level is done processing */
+	spin_lock(&cmd->cmd_lock);
 	cmd->cmd_sent_to_fw = 1;
+	spin_unlock(&cmd->cmd_lock);
 	cmd->ctio_flags = le16_to_cpu(pkt->u.status0.flags);
 
 	/* Memory Barrier */
@@ -3462,7 +3464,9 @@  int qlt_rdy_to_xfer(struct qla_tgt_cmd *cmd)
 		qlt_load_data_segments(&prm);
 
 	cmd->state = QLA_TGT_STATE_NEED_DATA;
+	spin_lock(&cmd->cmd_lock);
 	cmd->cmd_sent_to_fw = 1;
+	spin_unlock(&cmd->cmd_lock);
 	cmd->ctio_flags = le16_to_cpu(pkt->u.status0.flags);
 
 	/* Memory Barrier */
diff --git a/drivers/scsi/qla2xxx/qla_target.h b/drivers/scsi/qla2xxx/qla_target.h
index 6a59c99a63da..91403269b204 100644
--- a/drivers/scsi/qla2xxx/qla_target.h
+++ b/drivers/scsi/qla2xxx/qla_target.h
@@ -900,6 +900,7 @@  struct qla_tgt_cmd {
 	unsigned int aborted:1;
 	unsigned int data_work:1;
 	unsigned int data_work_free:1;
+	unsigned int released:1;
 
 	struct scatterlist *sg;	/* cmd data buffer SG vector */
 	int sg_cnt;		/* SG segments count */
diff --git a/drivers/scsi/qla2xxx/tcm_qla2xxx.c b/drivers/scsi/qla2xxx/tcm_qla2xxx.c
index e03d12a5f986..7d3d4a82fe96 100644
--- a/drivers/scsi/qla2xxx/tcm_qla2xxx.c
+++ b/drivers/scsi/qla2xxx/tcm_qla2xxx.c
@@ -277,14 +277,25 @@  static void tcm_qla2xxx_free_mcmd(struct qla_tgt_mgmt_cmd *mcmd)
 static void tcm_qla2xxx_complete_free(struct work_struct *work)
 {
 	struct qla_tgt_cmd *cmd = container_of(work, struct qla_tgt_cmd, work);
+	bool released = false;
+	unsigned long flags;
 
 	cmd->cmd_in_wq = 0;
 
 	WARN_ON(cmd->trc_flags & TRC_CMD_FREE);
 
+	spin_lock_irqsave(&cmd->cmd_lock, flags);
 	cmd->qpair->tgt_counters.qla_core_ret_sta_ctio++;
 	cmd->trc_flags |= TRC_CMD_FREE;
-	transport_generic_free_cmd(&cmd->se_cmd, 0);
+	cmd->cmd_sent_to_fw = 0;
+	if (cmd->released)
+		released = true;
+	spin_unlock_irqrestore(&cmd->cmd_lock, flags);
+
+	if (released)
+		qlt_free_cmd(cmd);
+	else
+		transport_generic_free_cmd(&cmd->se_cmd, 0);
 }
 
 /*
@@ -325,6 +336,7 @@  static int tcm_qla2xxx_check_stop_free(struct se_cmd *se_cmd)
 static void tcm_qla2xxx_release_cmd(struct se_cmd *se_cmd)
 {
 	struct qla_tgt_cmd *cmd;
+	unsigned long flags;
 
 	if (se_cmd->se_cmd_flags & SCF_SCSI_TMR_CDB) {
 		struct qla_tgt_mgmt_cmd *mcmd = container_of(se_cmd,
@@ -332,9 +344,16 @@  static void tcm_qla2xxx_release_cmd(struct se_cmd *se_cmd)
 		qlt_free_mcmd(mcmd);
 		return;
 	}
-
 	cmd = container_of(se_cmd, struct qla_tgt_cmd, se_cmd);
-	qlt_free_cmd(cmd);
+
+	spin_lock_irqsave(&cmd->cmd_lock, flags);
+	if (cmd->cmd_sent_to_fw) {
+		cmd->released = 1;
+		spin_unlock_irqrestore(&cmd->cmd_lock, flags);
+	} else {
+		spin_unlock_irqrestore(&cmd->cmd_lock, flags);
+		qlt_free_cmd(cmd);
+	}
 }
 
 static void tcm_qla2xxx_release_session(struct kref *kref)
@@ -499,6 +518,7 @@  static int tcm_qla2xxx_handle_cmd(scsi_qla_host_t *vha, struct qla_tgt_cmd *cmd,
 static void tcm_qla2xxx_handle_data_work(struct work_struct *work)
 {
 	struct qla_tgt_cmd *cmd = container_of(work, struct qla_tgt_cmd, work);
+	unsigned long flags;
 
 	/*
 	 * Ensure that the complete FCP WRITE payload has been received.
@@ -506,6 +526,25 @@  static void tcm_qla2xxx_handle_data_work(struct work_struct *work)
 	 */
 	cmd->cmd_in_wq = 0;
 
+	spin_lock_irqsave(&cmd->cmd_lock, flags);
+	cmd->cmd_sent_to_fw = 0;
+
+	if (cmd->released) {
+		spin_unlock_irqrestore(&cmd->cmd_lock, flags);
+		qlt_free_cmd(cmd);
+		return;
+	}
+
+	cmd->data_work = 1;
+	if (cmd->aborted) {
+		cmd->data_work_free = 1;
+		spin_unlock_irqrestore(&cmd->cmd_lock, flags);
+
+		tcm_qla2xxx_free_cmd(cmd);
+		return;
+	}
+	spin_unlock_irqrestore(&cmd->cmd_lock, flags);
+
 	cmd->qpair->tgt_counters.qla_core_ret_ctio++;
 	if (!cmd->write_data_transferred) {
 		/*