Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit fc73648a authored by Hannes Reinecke's avatar Hannes Reinecke Committed by James Bottomley
Browse files

[SCSI] Handle MLQUEUE busy response in scsi_send_eh_cmnd 



scsi_send_eh_cmnd() is calling queuecommand() directly, so
it needs to check the return value here.
The only valid return codes for queuecommand() are 'busy'
states, so we need to wait for a bit to allow the LLDD
to recover.

Based on an earlier patch from Wen Xiong.

[jejb: fix confusion between msec and jiffies values and other issues]
[bvanassche: correct stall_for interval]
Cc: Wen Xiong <wenxiong@linux.vnet.ibm.com>
Cc: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: default avatarHannes Reinecke <hare@suse.de>
Signed-off-by: default avatarJames Bottomley <JBottomley@Parallels.com>
parent d522844a

drivers/scsi/scsi_error.c

+27 −10
Original line number Original line Diff line number Diff line
@@ -25,6 +25,7 @@ 
#include <linux/interrupt.h>

#include <linux/interrupt.h>

#include <linux/blkdev.h>

#include <linux/blkdev.h>

#include <linux/delay.h>

#include <linux/delay.h>

#include <linux/jiffies.h>





#include <scsi/scsi.h>

#include <scsi/scsi.h>

#include <scsi/scsi_cmnd.h>

#include <scsi/scsi_cmnd.h>
@@ -791,32 +792,48 @@ static int scsi_send_eh_cmnd(struct scsi_cmnd *scmd, unsigned char *cmnd, 
	struct scsi_device *sdev = scmd->device;

	struct scsi_device *sdev = scmd->device;

	struct Scsi_Host *shost = sdev->host;

	struct Scsi_Host *shost = sdev->host;

	DECLARE_COMPLETION_ONSTACK(done);

	DECLARE_COMPLETION_ONSTACK(done);

	unsigned long timeleft;

	unsigned long timeleft = timeout;

	struct scsi_eh_save ses;

	struct scsi_eh_save ses;

	const unsigned long stall_for = msecs_to_jiffies(100);

	int rtn;

	int rtn;





retry:

	scsi_eh_prep_cmnd(scmd, &ses, cmnd, cmnd_size, sense_bytes);

	scsi_eh_prep_cmnd(scmd, &ses, cmnd, cmnd_size, sense_bytes);

	shost->eh_action = &done;

	shost->eh_action = &done;





	scsi_log_send(scmd);

	scsi_log_send(scmd);

	scmd->scsi_done = scsi_eh_done;

	scmd->scsi_done = scsi_eh_done;

	shost->hostt->queuecommand(shost, scmd);

	rtn = shost->hostt->queuecommand(shost, scmd);



	if (rtn) {

		if (timeleft > stall_for) {

			scsi_eh_restore_cmnd(scmd, &ses);

			timeleft -= stall_for;

			msleep(jiffies_to_msecs(stall_for));

			goto retry;

		}

		/* signal not to enter either branch of the if () below */

		timeleft = 0;

		rtn = NEEDS_RETRY;

	} else {

		timeleft = wait_for_completion_timeout(&done, timeout);

		timeleft = wait_for_completion_timeout(&done, timeout);

	}





	shost->eh_action = NULL;

	shost->eh_action = NULL;





	scsi_log_completion(scmd, SUCCESS);

	scsi_log_completion(scmd, rtn);





	SCSI_LOG_ERROR_RECOVERY(3,

	SCSI_LOG_ERROR_RECOVERY(3,

		printk("%s: scmd: %p, timeleft: %ld\n",

		printk("%s: scmd: %p, timeleft: %ld\n",

			__func__, scmd, timeleft));

			__func__, scmd, timeleft));





	/*

	/*

	 * If there is time left scsi_eh_done got called, and we will

	 * If there is time left scsi_eh_done got called, and we will examine

	 * examine the actual status codes to see whether the command

	 * the actual status codes to see whether the command actually did

	 * actually did complete normally, else tell the host to forget

	 * complete normally, else if we have a zero return and no time left,

	 * about this command.

	 * the command must still be pending, so abort it and return FAILED.

	 * If we never actually managed to issue the command, because

	 * ->queuecommand() kept returning non zero, use the rtn = FAILED

	 * value above (so don't execute either branch of the if)

	 */

	 */

	if (timeleft) {

	if (timeleft) {

		rtn = scsi_eh_completed_normally(scmd);

		rtn = scsi_eh_completed_normally(scmd);
@@ -837,7 +854,7 @@ static int scsi_send_eh_cmnd(struct scsi_cmnd *scmd, unsigned char *cmnd, 
			rtn = FAILED;

			rtn = FAILED;

			break;

			break;

		}

		}

	} else {

	} else if (!rtn) {

		scsi_abort_eh_cmnd(scmd);

		scsi_abort_eh_cmnd(scmd);

		rtn = FAILED;

		rtn = FAILED;

	}

	}