Commit 8d24677e authored by Mike Christie's avatar Mike Christie Committed by Martin K. Petersen
Browse files

scsi: core: Have SCSI midlayer retry scsi_report_lun_scan() errors 



This has scsi_report_lun_scan() have the SCSI midlayer retry errors instead
of driving them itself.

There is one behavior change where we no longer retry when
scsi_execute_cmd() returns < 0, but we should be ok. We don't need to retry
for failures like the queue being removed, and for the case where there are
no tags/reqs the block layer waits/retries for us. For possible memory
allocation failures from blk_rq_map_kern() we use GFP_NOIO, so retrying
will probably not help.

Signed-off-by: default avatarMike Christie <michael.christie@oracle.com>
Link: https://lore.kernel.org/r/20240123002220.129141-14-michael.christie@oracle.com


Acked-by: default avatarChristoph Hellwig <hch@lst.de>
Signed-off-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
parent 21bdff48

drivers/scsi/scsi_scan.c

+33 −24
Original line number Diff line number Diff line
@@ -1416,14 +1416,34 @@ static int scsi_report_lun_scan(struct scsi_target *starget, blist_flags_t bflag 
	unsigned int length;

	u64 lun;

	unsigned int num_luns;

	unsigned int retries;

	int result;

	struct scsi_lun *lunp, *lun_data;

	struct scsi_sense_hdr sshdr;

	struct scsi_device *sdev;

	struct Scsi_Host *shost = dev_to_shost(&starget->dev);

	struct scsi_failure failure_defs[] = {

		{

			.sense = UNIT_ATTENTION,

			.asc = SCMD_FAILURE_ASC_ANY,

			.ascq = SCMD_FAILURE_ASCQ_ANY,

			.result = SAM_STAT_CHECK_CONDITION,

		},

		/* Fail all CCs except the UA above */

		{

			.sense = SCMD_FAILURE_SENSE_ANY,

			.result = SAM_STAT_CHECK_CONDITION,

		},

		/* Retry any other errors not listed above */

		{

			.result = SCMD_FAILURE_RESULT_ANY,

		},

		{}

	};

	struct scsi_failures failures = {

		.total_allowed = 3,

		.failure_definitions = failure_defs,

	};

	const struct scsi_exec_args exec_args = {

		.sshdr = &sshdr,

		.failures = &failures,

	};

	int ret = 0;
@@ -1494,29 +1514,18 @@ static int scsi_report_lun_scan(struct scsi_target *starget, blist_flags_t bflag 
	 * should come through as a check condition, and will not generate

	 * a retry.

	 */

	for (retries = 0; retries < 3; retries++) {

	scsi_failures_reset_retries(&failures);



	SCSI_LOG_SCAN_BUS(3, sdev_printk (KERN_INFO, sdev,

				"scsi scan: Sending REPORT LUNS to (try %d)\n",

				retries));

			  "scsi scan: Sending REPORT LUNS\n"));



		result = scsi_execute_cmd(sdev, scsi_cmd, REQ_OP_DRV_IN,

					  lun_data, length,

					  SCSI_REPORT_LUNS_TIMEOUT, 3,

	result = scsi_execute_cmd(sdev, scsi_cmd, REQ_OP_DRV_IN, lun_data,

				  length, SCSI_REPORT_LUNS_TIMEOUT, 3,

				  &exec_args);



	SCSI_LOG_SCAN_BUS(3, sdev_printk (KERN_INFO, sdev,

				"scsi scan: REPORT LUNS"

				" %s (try %d) result 0x%x\n",

				result ?  "failed" : "successful",

				retries, result));

		if (result == 0)

			break;

		else if (scsi_sense_valid(&sshdr)) {

			if (sshdr.sense_key != UNIT_ATTENTION)

				break;

		}

	}



			  "scsi scan: REPORT LUNS  %s result 0x%x\n",

			  result ?  "failed" : "successful", result));

	if (result) {

		/*

		 * The device probably does not support a REPORT LUN command