diff mbox series

[V2,1/4] pm80xx: make mpi_build_cmd locking consistent

Message ID 20201030060913.14886-2-Viswas.G@microchip.com.com
State New
Headers show
Series [V2,1/4] pm80xx: make mpi_build_cmd locking consistent | expand

Commit Message

Viswas G Oct. 30, 2020, 6:09 a.m. UTC
From: peter chang <dpf@google.com>

Driver submit all internal requests (like abort_task, event
acknowledgment etc.) through inbound queue 0. While submitting those,
driver does not acquire any lock and it may lead to a race when there 
is an IO request coming in CPU0 and submitted through inbound queue 0. 
To avoid this, lock acquisition has been moved to pm8001_mpi_build_cmd().
All command submission will go through this path.

Signed-off-by: peter chang <dpf@google.com>
Signed-off-by: Viswas G <Viswas.G@microchip.com>
Signed-off-by: Ruksar Devadi <Ruksar.devadi@microchip.com>
Signed-off-by: Radha Ramachandran <radha@google.com>
---
 drivers/scsi/pm8001/pm8001_hwi.c | 21 +++++++++++++++------
 drivers/scsi/pm8001/pm80xx_hwi.c |  8 --------
 2 files changed, 15 insertions(+), 14 deletions(-)

Comments

Jinpu Wang Oct. 30, 2020, 6:51 a.m. UTC | #1
On Fri, Oct 30, 2020 at 6:59 AM Viswas G <Viswas.G@microchip.com.com> wrote:
>

> From: peter chang <dpf@google.com>

>

> Driver submit all internal requests (like abort_task, event

> acknowledgment etc.) through inbound queue 0. While submitting those,

> driver does not acquire any lock and it may lead to a race when there

> is an IO request coming in CPU0 and submitted through inbound queue 0.

> To avoid this, lock acquisition has been moved to pm8001_mpi_build_cmd().

> All command submission will go through this path.

>

> Signed-off-by: peter chang <dpf@google.com>

> Signed-off-by: Viswas G <Viswas.G@microchip.com>

> Signed-off-by: Ruksar Devadi <Ruksar.devadi@microchip.com>

> Signed-off-by: Radha Ramachandran <radha@google.com>

This commit message is easy to follow.
Thanks.
Acked-by: Jack Wang <jinpu.wang@cloud.ionos.com>

> ---

>  drivers/scsi/pm8001/pm8001_hwi.c | 21 +++++++++++++++------

>  drivers/scsi/pm8001/pm80xx_hwi.c |  8 --------

>  2 files changed, 15 insertions(+), 14 deletions(-)

>

> diff --git a/drivers/scsi/pm8001/pm8001_hwi.c b/drivers/scsi/pm8001/pm8001_hwi.c

> index 2b7b2954ec31..597d7a096a97 100644

> --- a/drivers/scsi/pm8001/pm8001_hwi.c

> +++ b/drivers/scsi/pm8001/pm8001_hwi.c

> @@ -1356,12 +1356,19 @@ int pm8001_mpi_build_cmd(struct pm8001_hba_info *pm8001_ha,

>  {

>         u32 Header = 0, hpriority = 0, bc = 1, category = 0x02;

>         void *pMessage;

> -

> -       if (pm8001_mpi_msg_free_get(circularQ, pm8001_ha->iomb_size,

> -               &pMessage) < 0) {

> +       unsigned long flags;

> +       int q_index = circularQ - pm8001_ha->inbnd_q_tbl;

> +       int rv = -1;

> +

> +       WARN_ON(q_index >= PM8001_MAX_INB_NUM);

> +       spin_lock_irqsave(&circularQ->iq_lock, flags);

> +       rv = pm8001_mpi_msg_free_get(circularQ, pm8001_ha->iomb_size,

> +                       &pMessage);

> +       if (rv < 0) {

>                 PM8001_IO_DBG(pm8001_ha,

> -                       pm8001_printk("No free mpi buffer\n"));

> -               return -ENOMEM;

> +                             pm8001_printk("No free mpi buffer\n"));

> +               rv = -ENOMEM;

> +               goto done;

>         }

>

>         if (nb > (pm8001_ha->iomb_size - sizeof(struct mpi_msg_hdr)))

> @@ -1384,7 +1391,9 @@ int pm8001_mpi_build_cmd(struct pm8001_hba_info *pm8001_ha,

>                 pm8001_printk("INB Q %x OPCODE:%x , UPDATED PI=%d CI=%d\n",

>                         responseQueue, opCode, circularQ->producer_idx,

>                         circularQ->consumer_index));

> -       return 0;

> +done:

> +       spin_unlock_irqrestore(&circularQ->iq_lock, flags);

> +       return rv;

>  }

>

>  u32 pm8001_mpi_msg_free_set(struct pm8001_hba_info *pm8001_ha, void *pMsg,

> diff --git a/drivers/scsi/pm8001/pm80xx_hwi.c b/drivers/scsi/pm8001/pm80xx_hwi.c

> index 7593f248afb2..5fe50e0effcd 100644

> --- a/drivers/scsi/pm8001/pm80xx_hwi.c

> +++ b/drivers/scsi/pm8001/pm80xx_hwi.c

> @@ -4281,7 +4281,6 @@ static int pm80xx_chip_smp_req(struct pm8001_hba_info *pm8001_ha,

>         char *preq_dma_addr = NULL;

>         __le64 tmp_addr;

>         u32 i, length;

> -       unsigned long flags;

>

>         memset(&smp_cmd, 0, sizeof(smp_cmd));

>         /*

> @@ -4377,10 +4376,8 @@ static int pm80xx_chip_smp_req(struct pm8001_hba_info *pm8001_ha,

>

>         build_smp_cmd(pm8001_dev->device_id, smp_cmd.tag,

>                                 &smp_cmd, pm8001_ha->smp_exp_mode, length);

> -       spin_lock_irqsave(&circularQ->iq_lock, flags);

>         rc = pm8001_mpi_build_cmd(pm8001_ha, circularQ, opc, &smp_cmd,

>                         sizeof(smp_cmd), 0);

> -       spin_unlock_irqrestore(&circularQ->iq_lock, flags);

>         if (rc)

>                 goto err_out_2;

>         return 0;

> @@ -4444,7 +4441,6 @@ static int pm80xx_chip_ssp_io_req(struct pm8001_hba_info *pm8001_ha,

>         u64 phys_addr, start_addr, end_addr;

>         u32 end_addr_high, end_addr_low;

>         struct inbound_queue_table *circularQ;

> -       unsigned long flags;

>         u32 q_index, cpu_id;

>         u32 opc = OPC_INB_SSPINIIOSTART;

>         memset(&ssp_cmd, 0, sizeof(ssp_cmd));

> @@ -4582,10 +4578,8 @@ static int pm80xx_chip_ssp_io_req(struct pm8001_hba_info *pm8001_ha,

>                         ssp_cmd.esgl = 0;

>                 }

>         }

> -       spin_lock_irqsave(&circularQ->iq_lock, flags);

>         ret = pm8001_mpi_build_cmd(pm8001_ha, circularQ, opc,

>                         &ssp_cmd, sizeof(ssp_cmd), q_index);

> -       spin_unlock_irqrestore(&circularQ->iq_lock, flags);

>         return ret;

>  }

>

> @@ -4819,10 +4813,8 @@ static int pm80xx_chip_sata_req(struct pm8001_hba_info *pm8001_ha,

>                         }

>                 }

>         }

> -       spin_lock_irqsave(&circularQ->iq_lock, flags);

>         ret = pm8001_mpi_build_cmd(pm8001_ha, circularQ, opc,

>                         &sata_cmd, sizeof(sata_cmd), q_index);

> -       spin_unlock_irqrestore(&circularQ->iq_lock, flags);

>         return ret;

>  }

>

> --

> 2.16.3

>
diff mbox series

Patch

diff --git a/drivers/scsi/pm8001/pm8001_hwi.c b/drivers/scsi/pm8001/pm8001_hwi.c
index 2b7b2954ec31..597d7a096a97 100644
--- a/drivers/scsi/pm8001/pm8001_hwi.c
+++ b/drivers/scsi/pm8001/pm8001_hwi.c
@@ -1356,12 +1356,19 @@  int pm8001_mpi_build_cmd(struct pm8001_hba_info *pm8001_ha,
 {
 	u32 Header = 0, hpriority = 0, bc = 1, category = 0x02;
 	void *pMessage;
-
-	if (pm8001_mpi_msg_free_get(circularQ, pm8001_ha->iomb_size,
-		&pMessage) < 0) {
+	unsigned long flags;
+	int q_index = circularQ - pm8001_ha->inbnd_q_tbl;
+	int rv = -1;
+
+	WARN_ON(q_index >= PM8001_MAX_INB_NUM);
+	spin_lock_irqsave(&circularQ->iq_lock, flags);
+	rv = pm8001_mpi_msg_free_get(circularQ, pm8001_ha->iomb_size,
+			&pMessage);
+	if (rv < 0) {
 		PM8001_IO_DBG(pm8001_ha,
-			pm8001_printk("No free mpi buffer\n"));
-		return -ENOMEM;
+			      pm8001_printk("No free mpi buffer\n"));
+		rv = -ENOMEM;
+		goto done;
 	}
 
 	if (nb > (pm8001_ha->iomb_size - sizeof(struct mpi_msg_hdr)))
@@ -1384,7 +1391,9 @@  int pm8001_mpi_build_cmd(struct pm8001_hba_info *pm8001_ha,
 		pm8001_printk("INB Q %x OPCODE:%x , UPDATED PI=%d CI=%d\n",
 			responseQueue, opCode, circularQ->producer_idx,
 			circularQ->consumer_index));
-	return 0;
+done:
+	spin_unlock_irqrestore(&circularQ->iq_lock, flags);
+	return rv;
 }
 
 u32 pm8001_mpi_msg_free_set(struct pm8001_hba_info *pm8001_ha, void *pMsg,
diff --git a/drivers/scsi/pm8001/pm80xx_hwi.c b/drivers/scsi/pm8001/pm80xx_hwi.c
index 7593f248afb2..5fe50e0effcd 100644
--- a/drivers/scsi/pm8001/pm80xx_hwi.c
+++ b/drivers/scsi/pm8001/pm80xx_hwi.c
@@ -4281,7 +4281,6 @@  static int pm80xx_chip_smp_req(struct pm8001_hba_info *pm8001_ha,
 	char *preq_dma_addr = NULL;
 	__le64 tmp_addr;
 	u32 i, length;
-	unsigned long flags;
 
 	memset(&smp_cmd, 0, sizeof(smp_cmd));
 	/*
@@ -4377,10 +4376,8 @@  static int pm80xx_chip_smp_req(struct pm8001_hba_info *pm8001_ha,
 
 	build_smp_cmd(pm8001_dev->device_id, smp_cmd.tag,
 				&smp_cmd, pm8001_ha->smp_exp_mode, length);
-	spin_lock_irqsave(&circularQ->iq_lock, flags);
 	rc = pm8001_mpi_build_cmd(pm8001_ha, circularQ, opc, &smp_cmd,
 			sizeof(smp_cmd), 0);
-	spin_unlock_irqrestore(&circularQ->iq_lock, flags);
 	if (rc)
 		goto err_out_2;
 	return 0;
@@ -4444,7 +4441,6 @@  static int pm80xx_chip_ssp_io_req(struct pm8001_hba_info *pm8001_ha,
 	u64 phys_addr, start_addr, end_addr;
 	u32 end_addr_high, end_addr_low;
 	struct inbound_queue_table *circularQ;
-	unsigned long flags;
 	u32 q_index, cpu_id;
 	u32 opc = OPC_INB_SSPINIIOSTART;
 	memset(&ssp_cmd, 0, sizeof(ssp_cmd));
@@ -4582,10 +4578,8 @@  static int pm80xx_chip_ssp_io_req(struct pm8001_hba_info *pm8001_ha,
 			ssp_cmd.esgl = 0;
 		}
 	}
-	spin_lock_irqsave(&circularQ->iq_lock, flags);
 	ret = pm8001_mpi_build_cmd(pm8001_ha, circularQ, opc,
 			&ssp_cmd, sizeof(ssp_cmd), q_index);
-	spin_unlock_irqrestore(&circularQ->iq_lock, flags);
 	return ret;
 }
 
@@ -4819,10 +4813,8 @@  static int pm80xx_chip_sata_req(struct pm8001_hba_info *pm8001_ha,
 			}
 		}
 	}
-	spin_lock_irqsave(&circularQ->iq_lock, flags);
 	ret = pm8001_mpi_build_cmd(pm8001_ha, circularQ, opc,
 			&sata_cmd, sizeof(sata_cmd), q_index);
-	spin_unlock_irqrestore(&circularQ->iq_lock, flags);
 	return ret;
 }