Commit 44678553 authored by Sergey Samoylenko's avatar Sergey Samoylenko Committed by Martin K. Petersen
Browse files

scsi: target: Allows backend drivers to fail with specific sense codes 

Currently, backend drivers can fail I/O with SAM_STAT_CHECK_CONDITION which
gets us TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE.

Add a new helper that allows backend drivers to fail with specific sense
codes.

This is based on a patch from Mike Christie <michael.christie@oracle.com>.

Cc: Mike Christie <michael.christie@oracle.com>
Link: https://lore.kernel.org/r/20210803145410.80147-2-s.samoylenko@yadro.com


Reviewed-by: default avatarDavid Disseldorp <ddiss@suse.de>
Signed-off-by: default avatarSergey Samoylenko <s.samoylenko@yadro.com>
Signed-off-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
parent 5f492a7a

drivers/target/target_core_transport.c

+12 −3
Original line number Diff line number Diff line
@@ -736,8 +736,7 @@ static void target_complete_failure_work(struct work_struct *work) 
{

	struct se_cmd *cmd = container_of(work, struct se_cmd, work);



	transport_generic_request_failure(cmd,

			TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE);

	transport_generic_request_failure(cmd, cmd->sense_reason);

}



/*
@@ -855,7 +854,8 @@ static bool target_cmd_interrupted(struct se_cmd *cmd) 
}



/* May be called from interrupt context so must not sleep. */

void target_complete_cmd(struct se_cmd *cmd, u8 scsi_status)

void target_complete_cmd_with_sense(struct se_cmd *cmd, u8 scsi_status,

				    sense_reason_t sense_reason)

{

	struct se_wwn *wwn = cmd->se_sess->se_tpg->se_tpg_wwn;

	int success, cpu;
@@ -865,6 +865,7 @@ void target_complete_cmd(struct se_cmd *cmd, u8 scsi_status) 
		return;



	cmd->scsi_status = scsi_status;

	cmd->sense_reason = sense_reason;



	spin_lock_irqsave(&cmd->t_state_lock, flags);

	switch (cmd->scsi_status) {
@@ -893,6 +894,14 @@ void target_complete_cmd(struct se_cmd *cmd, u8 scsi_status) 


	queue_work_on(cpu, target_completion_wq, &cmd->work);

}

EXPORT_SYMBOL(target_complete_cmd_with_sense);



void target_complete_cmd(struct se_cmd *cmd, u8 scsi_status)

{

	target_complete_cmd_with_sense(cmd, scsi_status, scsi_status ?

			      TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE :

			      TCM_NO_SENSE);

}

EXPORT_SYMBOL(target_complete_cmd);



void target_set_cmd_data_length(struct se_cmd *cmd, int length)

include/target/target_core_backend.h

+1 −0
Original line number Diff line number Diff line
@@ -75,6 +75,7 @@ void target_backend_unregister(const struct target_backend_ops *); 


void	target_complete_cmd(struct se_cmd *, u8);

void	target_set_cmd_data_length(struct se_cmd *, int);

void	target_complete_cmd_with_sense(struct se_cmd *, u8, sense_reason_t);

void	target_complete_cmd_with_length(struct se_cmd *, u8, int);



void	transport_copy_sense_to_cmd(struct se_cmd *, unsigned char *);

include/target/target_core_base.h

+2 −0
Original line number Diff line number Diff line
@@ -457,6 +457,8 @@ enum target_core_dif_check { 
#define TCM_ACA_TAG	0x24



struct se_cmd {

	/* Used for fail with specific sense codes */

	sense_reason_t		sense_reason;

	/* SAM response code being sent to initiator */

	u8			scsi_status;

	u16			scsi_sense_length;