diff mbox series

[01/11] pmcraid: Select device in pmcraid_eh_bus_reset_handler()

Message ID 20220502215416.5351-2-hare@suse.de (mailing list archive)
State Deferred
Headers show
Series scsi: EH rework prep patches, part 2 | expand

Commit Message

Hannes Reinecke May 2, 2022, 9:54 p.m. UTC 
The reset code requires a device to be selected, but we shouldn't
rely on the command to provide a device for us. So select the first
device on the bus when sending down a bus reset.

Signed-off-by: Hannes Reinecke <hare@suse.com>
---
 drivers/scsi/pmcraid.c | 46 ++++++++++++++++++++++++++++++++++--------
 1 file changed, 38 insertions(+), 8 deletions(-)

Comments

Christoph Hellwig May 3, 2022, 2:25 p.m. UTC | #1 
Looks good:

Reviewed-by: Christoph Hellwig <hch@lst.de>
Bart Van Assche May 3, 2022, 4:23 p.m. UTC | #2 
On 5/2/22 14:54, Hannes Reinecke wrote:
> The reset code requires a device to be selected, but we shouldn't
                                                        ^^^^^^^^^^^^
> rely on the command to provide a device for us. So select the first
> device on the bus when sending down a bus reset.
Why is it that we shouldn't rely on the SCSI EH to provide a device? I 
think this should be explained in the commit message.

Thanks,

Bart.
Hannes Reinecke May 3, 2022, 6:33 p.m. UTC | #3 
On 5/3/22 09:23, Bart Van Assche wrote:
> On 5/2/22 14:54, Hannes Reinecke wrote:
>> The reset code requires a device to be selected, but we shouldn't
>                                                         ^^^^^^^^^^^^
>> rely on the command to provide a device for us. So select the first
>> device on the bus when sending down a bus reset.
> Why is it that we shouldn't rely on the SCSI EH to provide a device? I 
> think this should be explained in the commit message.
> 
Scope.

We should rely on the _device_, we should rely on the _bus_.

Cheers,

Hannes
diff mbox series

Patch

diff --git a/drivers/scsi/pmcraid.c b/drivers/scsi/pmcraid.c
index 3d5cd337a2a6..d508e81a03db 100644
--- a/drivers/scsi/pmcraid.c
+++ b/drivers/scsi/pmcraid.c
@@ -2691,7 +2691,7 @@  static int pmcraid_error_handler(struct pmcraid_cmd *cmd)
  *	SUCCESS / FAILED
  */
 static int pmcraid_reset_device(
-	struct scsi_cmnd *scsi_cmd,
+	struct scsi_device *scsi_dev,
 	unsigned long timeout,
 	u8 modifier)
 {
@@ -2703,11 +2703,11 @@  static int pmcraid_reset_device(
 	u32 ioasc;
 
 	pinstance =
-		(struct pmcraid_instance *)scsi_cmd->device->host->hostdata;
-	res = scsi_cmd->device->hostdata;
+		(struct pmcraid_instance *)scsi_dev->host->hostdata;
+	res = scsi_dev->hostdata;
 
 	if (!res) {
-		sdev_printk(KERN_ERR, scsi_cmd->device,
+		sdev_printk(KERN_ERR, scsi_dev,
 			    "reset_device: NULL resource pointer\n");
 		return FAILED;
 	}
@@ -3018,16 +3018,46 @@  static int pmcraid_eh_device_reset_handler(struct scsi_cmnd *scmd)
 {
 	scmd_printk(KERN_INFO, scmd,
 		    "resetting device due to an I/O command timeout.\n");
-	return pmcraid_reset_device(scmd,
+	return pmcraid_reset_device(scmd->device,
 				    PMCRAID_INTERNAL_TIMEOUT,
 				    RESET_DEVICE_LUN);
 }
 
 static int pmcraid_eh_bus_reset_handler(struct scsi_cmnd *scmd)
 {
-	scmd_printk(KERN_INFO, scmd,
+	struct Scsi_Host *host = scmd->device->host;
+	struct pmcraid_instance *pinstance =
+		(struct pmcraid_instance *)host->hostdata;
+	struct pmcraid_resource_entry *res = NULL;
+	struct pmcraid_resource_entry *temp;
+	struct scsi_device *sdev = NULL;
+	unsigned long lock_flags;
+
+	/*
+	 * The reset device code insists on us passing down
+	 * a device, so grab the first device on the bus.
+	 */
+	spin_lock_irqsave(&pinstance->resource_lock, lock_flags);
+	list_for_each_entry(temp, &pinstance->used_res_q, queue) {
+		if (scmd->device->channel == PMCRAID_VSET_BUS_ID &&
+		    RES_IS_VSET(temp->cfg_entry)) {
+			res = temp;
+			break;
+		} else if (scmd->device->channel == PMCRAID_PHYS_BUS_ID &&
+			   RES_IS_GSCSI(temp->cfg_entry)) {
+			res = temp;
+			break;
+		}
+	}
+	if (res)
+		sdev = res->scsi_dev;
+	spin_unlock_irqrestore(&pinstance->resource_lock, lock_flags);
+	if (!sdev)
+		return FAILED;
+
+	sdev_printk(KERN_INFO, sdev,
 		    "Doing bus reset due to an I/O command timeout.\n");
-	return pmcraid_reset_device(scmd,
+	return pmcraid_reset_device(sdev,
 				    PMCRAID_RESET_BUS_TIMEOUT,
 				    RESET_DEVICE_BUS);
 }
@@ -3036,7 +3066,7 @@  static int pmcraid_eh_target_reset_handler(struct scsi_cmnd *scmd)
 {
 	scmd_printk(KERN_INFO, scmd,
 		    "Doing target reset due to an I/O command timeout.\n");
-	return pmcraid_reset_device(scmd,
+	return pmcraid_reset_device(scmd->device,
 				    PMCRAID_INTERNAL_TIMEOUT,
 				    RESET_DEVICE_TARGET);
 }