This patch closes up some potential race conditions observed in
the error handling paths in ipr while debugging an issue resulting
in a hang with SATA error handling. These patches ensure we are
holding the correct lock when adding and removing commands from
the free and pending queues in some error scenarios.
Signed-off-by: Brian King <brking@xxxxxxxxxxxxxxxxxx>
---
drivers/scsi/ipr.c | 106 ++++++++++++++++++++++++++++++++++++++++++++++-------
1 file changed, 93 insertions(+), 13 deletions(-)
diff -puN drivers/scsi/ipr.c~ipr_eh_locking_fixes drivers/scsi/ipr.c
--- linux-2.6.git/drivers/scsi/ipr.c~ipr_eh_locking_fixes 2017-03-13 14:56:49.994452448 -0500
+++ linux-2.6.git-bjking1/drivers/scsi/ipr.c 2017-03-13 14:56:50.000452424 -0500
@@ -820,7 +820,7 @@ static int ipr_set_pcix_cmd_reg(struct i
}
/**
- * ipr_sata_eh_done - done function for aborted SATA commands
+ * __ipr_sata_eh_done - done function for aborted SATA commands
* @ipr_cmd: ipr command struct
*
* This function is invoked for ops generated to SATA
@@ -829,7 +829,7 @@ static int ipr_set_pcix_cmd_reg(struct i
* Return value:
* none
**/
-static void ipr_sata_eh_done(struct ipr_cmnd *ipr_cmd)
+static void __ipr_sata_eh_done(struct ipr_cmnd *ipr_cmd)
{
struct ata_queued_cmd *qc = ipr_cmd->qc;
struct ipr_sata_port *sata_port = qc->ap->private_data;
@@ -843,7 +843,27 @@ static void ipr_sata_eh_done(struct ipr_
}
/**
- * ipr_scsi_eh_done - mid-layer done function for aborted ops
+ * ipr_sata_eh_done - done function for aborted SATA commands
+ * @ipr_cmd: ipr command struct
+ *
+ * This function is invoked for ops generated to SATA
+ * devices which are being aborted.
+ *
+ * Return value:
+ * none
+ **/
+static void ipr_sata_eh_done(struct ipr_cmnd *ipr_cmd)
+{
+ struct ipr_hrr_queue *hrrq = ipr_cmd->hrrq;
+ unsigned long hrrq_flags;
+
+ spin_lock_irqsave(&hrrq->_lock, hrrq_flags);
+ __ipr_sata_eh_done(ipr_cmd);
+ spin_unlock_irqrestore(&hrrq->_lock, hrrq_flags);
+}
+
+/**
+ * __ipr_scsi_eh_done - mid-layer done function for aborted ops
* @ipr_cmd: ipr command struct
*
* This function is invoked by the interrupt handler for
@@ -852,7 +872,7 @@ static void ipr_sata_eh_done(struct ipr_
* Return value:
* none
**/
-static void ipr_scsi_eh_done(struct ipr_cmnd *ipr_cmd)
+static void __ipr_scsi_eh_done(struct ipr_cmnd *ipr_cmd)
{
struct scsi_cmnd *scsi_cmd = ipr_cmd->scsi_cmd;
@@ -866,6 +886,26 @@ static void ipr_scsi_eh_done(struct ipr_
}
/**
+ * ipr_scsi_eh_done - mid-layer done function for aborted ops
+ * @ipr_cmd: ipr command struct
+ *
+ * This function is invoked by the interrupt handler for
+ * ops generated by the SCSI mid-layer which are being aborted.
+ *
+ * Return value:
+ * none
+ **/
+static void ipr_scsi_eh_done(struct ipr_cmnd *ipr_cmd)
+{
+ unsigned long hrrq_flags;
+ struct ipr_hrr_queue *hrrq = ipr_cmd->hrrq;
+
+ spin_lock_irqsave(&hrrq->_lock, hrrq_flags);
+ __ipr_scsi_eh_done(ipr_cmd);
+ spin_unlock_irqrestore(&hrrq->_lock, hrrq_flags);
+}
+
+/**
* ipr_fail_all_ops - Fails all outstanding ops.
* @ioa_cfg: ioa config struct
*
@@ -892,9 +932,9 @@ static void ipr_fail_all_ops(struct ipr_
cpu_to_be32(IPR_DRIVER_ILID);
if (ipr_cmd->scsi_cmd)
- ipr_cmd->done = ipr_scsi_eh_done;
+ ipr_cmd->done = __ipr_scsi_eh_done;
else if (ipr_cmd->qc)
- ipr_cmd->done = ipr_sata_eh_done;
+ ipr_cmd->done = __ipr_sata_eh_done;
ipr_trc_hook(ipr_cmd, IPR_TRACE_FINISH,
IPR_IOASC_IOA_WAS_RESET);
@@ -5948,7 +5988,7 @@ static int ipr_build_ioadl(struct ipr_io
}
/**
- * ipr_erp_done - Process completion of ERP for a device
+ * __ipr_erp_done - Process completion of ERP for a device
* @ipr_cmd: ipr command struct
*
* This function copies the sense buffer into the scsi_cmd
@@ -5957,7 +5997,7 @@ static int ipr_build_ioadl(struct ipr_io
* Return value:
* nothing
**/
-static void ipr_erp_done(struct ipr_cmnd *ipr_cmd)
+static void __ipr_erp_done(struct ipr_cmnd *ipr_cmd)
{
struct scsi_cmnd *scsi_cmd = ipr_cmd->scsi_cmd;
struct ipr_resource_entry *res = scsi_cmd->device->hostdata;
@@ -5985,6 +6025,26 @@ static void ipr_erp_done(struct ipr_cmnd
}
/**
+ * ipr_erp_done - Process completion of ERP for a device
+ * @ipr_cmd: ipr command struct
+ *
+ * This function copies the sense buffer into the scsi_cmd
+ * struct and pushes the scsi_done function.
+ *
+ * Return value:
+ * nothing
+ **/
+static void ipr_erp_done(struct ipr_cmnd *ipr_cmd)
+{
+ struct ipr_hrr_queue *hrrq = ipr_cmd->hrrq;
+ unsigned long hrrq_flags;
+
+ spin_lock_irqsave(&hrrq->_lock, hrrq_flags);
+ __ipr_erp_done(ipr_cmd);
+ spin_unlock_irqrestore(&hrrq->_lock, hrrq_flags);
+}
+
+/**
* ipr_reinit_ipr_cmnd_for_erp - Re-initialize a cmnd block to be used for ERP
* @ipr_cmd: ipr command struct
*
@@ -6016,7 +6076,7 @@ static void ipr_reinit_ipr_cmnd_for_erp(
}
/**
- * ipr_erp_request_sense - Send request sense to a device
+ * __ipr_erp_request_sense - Send request sense to a device
* @ipr_cmd: ipr command struct
*
* This function sends a request sense to a device as a result
@@ -6025,13 +6085,13 @@ static void ipr_reinit_ipr_cmnd_for_erp(
* Return value:
* nothing
**/
-static void ipr_erp_request_sense(struct ipr_cmnd *ipr_cmd)
+static void __ipr_erp_request_sense(struct ipr_cmnd *ipr_cmd)
{
struct ipr_cmd_pkt *cmd_pkt = &ipr_cmd->ioarcb.cmd_pkt;
u32 ioasc = be32_to_cpu(ipr_cmd->s.ioasa.hdr.ioasc);
if (IPR_IOASC_SENSE_KEY(ioasc) > 0) {
- ipr_erp_done(ipr_cmd);
+ __ipr_erp_done(ipr_cmd);
return;
}
@@ -6052,6 +6112,26 @@ static void ipr_erp_request_sense(struct
}
/**
+ * ipr_erp_request_sense - Send request sense to a device
+ * @ipr_cmd: ipr command struct
+ *
+ * This function sends a request sense to a device as a result
+ * of a check condition.
+ *
+ * Return value:
+ * nothing
+ **/
+static void ipr_erp_request_sense(struct ipr_cmnd *ipr_cmd)
+{
+ struct ipr_hrr_queue *hrrq = ipr_cmd->hrrq;
+ unsigned long hrrq_flags;
+
+ spin_lock_irqsave(&hrrq->_lock, hrrq_flags);
+ __ipr_erp_request_sense(ipr_cmd);
+ spin_unlock_irqrestore(&hrrq->_lock, hrrq_flags);
+}
+
+/**
* ipr_erp_cancel_all - Send cancel all to a device
* @ipr_cmd: ipr command struct
*
@@ -6074,7 +6154,7 @@ static void ipr_erp_cancel_all(struct ip
ipr_reinit_ipr_cmnd_for_erp(ipr_cmd);
if (!scsi_cmd->device->simple_tags) {
- ipr_erp_request_sense(ipr_cmd);
+ __ipr_erp_request_sense(ipr_cmd);
return;
}
@@ -6294,7 +6374,7 @@ static void ipr_erp_start(struct ipr_ioa
u32 masked_ioasc = ioasc & IPR_IOASC_IOASC_MASK;
if (!res) {
- ipr_scsi_eh_done(ipr_cmd);
+ __ipr_scsi_eh_done(ipr_cmd);
return;
}
_
