scsi: Only add commands to the device command list if required by the LLD

Just like for the scsi-mq code path, in the single queue SCSI code path
only add commands to the per-device command list if required by the SCSI
LLD. This patch will make it easier to merge the single-queue and
multiqueue command initialization code.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Cc: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
This commit is contained in:
Bart Van Assche 2017-06-02 14:21:58 -07:00 committed by Martin K. Petersen
parent 255ee9320e
commit 2dd6fb5957
3 changed files with 35 additions and 28 deletions

View File

@ -108,14 +108,7 @@ EXPORT_SYMBOL(scsi_sd_pm_domain);
*/
void scsi_put_command(struct scsi_cmnd *cmd)
{
unsigned long flags;
/* serious error if the command hasn't come from a device list */
spin_lock_irqsave(&cmd->device->list_lock, flags);
BUG_ON(list_empty(&cmd->list));
list_del_init(&cmd->list);
spin_unlock_irqrestore(&cmd->device->list_lock, flags);
scsi_del_cmd_from_list(cmd);
BUG_ON(delayed_work_pending(&cmd->abort_work));
}

View File

@ -584,19 +584,9 @@ static void scsi_mq_free_sgtables(struct scsi_cmnd *cmd)
static void scsi_mq_uninit_cmd(struct scsi_cmnd *cmd)
{
struct scsi_device *sdev = cmd->device;
struct Scsi_Host *shost = sdev->host;
unsigned long flags;
scsi_mq_free_sgtables(cmd);
scsi_uninit_cmd(cmd);
if (shost->use_cmd_list) {
BUG_ON(list_empty(&cmd->list));
spin_lock_irqsave(&sdev->list_lock, flags);
list_del_init(&cmd->list);
spin_unlock_irqrestore(&sdev->list_lock, flags);
}
scsi_del_cmd_from_list(cmd);
}
/*
@ -1134,12 +1124,40 @@ int scsi_init_io(struct scsi_cmnd *cmd)
}
EXPORT_SYMBOL(scsi_init_io);
/* Add a command to the list used by the aacraid and dpt_i2o drivers */
void scsi_add_cmd_to_list(struct scsi_cmnd *cmd)
{
struct scsi_device *sdev = cmd->device;
struct Scsi_Host *shost = sdev->host;
unsigned long flags;
if (shost->use_cmd_list) {
spin_lock_irqsave(&sdev->list_lock, flags);
list_add_tail(&cmd->list, &sdev->cmd_list);
spin_unlock_irqrestore(&sdev->list_lock, flags);
}
}
/* Remove a command from the list used by the aacraid and dpt_i2o drivers */
void scsi_del_cmd_from_list(struct scsi_cmnd *cmd)
{
struct scsi_device *sdev = cmd->device;
struct Scsi_Host *shost = sdev->host;
unsigned long flags;
if (shost->use_cmd_list) {
spin_lock_irqsave(&sdev->list_lock, flags);
BUG_ON(list_empty(&cmd->list));
list_del_init(&cmd->list);
spin_unlock_irqrestore(&sdev->list_lock, flags);
}
}
void scsi_init_command(struct scsi_device *dev, struct scsi_cmnd *cmd)
{
void *buf = cmd->sense_buffer;
void *prot = cmd->prot_sdb;
unsigned int unchecked_isa_dma = cmd->flags & SCMD_UNCHECKED_ISA_DMA;
unsigned long flags;
/* zero out the cmd, except for the embedded scsi_request */
memset((char *)cmd + sizeof(cmd->req), 0,
@ -1152,9 +1170,7 @@ void scsi_init_command(struct scsi_device *dev, struct scsi_cmnd *cmd)
INIT_DELAYED_WORK(&cmd->abort_work, scmd_eh_abort_handler);
cmd->jiffies_at_alloc = jiffies;
spin_lock_irqsave(&dev->list_lock, flags);
list_add_tail(&cmd->list, &dev->cmd_list);
spin_unlock_irqrestore(&dev->list_lock, flags);
scsi_add_cmd_to_list(cmd);
}
static int scsi_setup_scsi_cmnd(struct scsi_device *sdev, struct request *req)
@ -1871,11 +1887,7 @@ static int scsi_mq_prep_fn(struct request *req)
INIT_DELAYED_WORK(&cmd->abort_work, scmd_eh_abort_handler);
cmd->jiffies_at_alloc = jiffies;
if (shost->use_cmd_list) {
spin_lock_irq(&sdev->list_lock);
list_add_tail(&cmd->list, &sdev->cmd_list);
spin_unlock_irq(&sdev->list_lock);
}
scsi_add_cmd_to_list(cmd);
sg = (void *)cmd + sizeof(struct scsi_cmnd) + shost->hostt->cmd_size;
cmd->sdb.table.sgl = sg;

View File

@ -80,6 +80,8 @@ int scsi_eh_get_sense(struct list_head *work_q,
int scsi_noretry_cmd(struct scsi_cmnd *scmd);
/* scsi_lib.c */
extern void scsi_add_cmd_to_list(struct scsi_cmnd *cmd);
extern void scsi_del_cmd_from_list(struct scsi_cmnd *cmd);
extern int scsi_maybe_unblock_host(struct scsi_device *sdev);
extern void scsi_device_unbusy(struct scsi_device *sdev);
extern void scsi_queue_insert(struct scsi_cmnd *cmd, int reason);