Re: [PATCH 4.10 15/17] qla2xxx: Allow vref count to timeout on vport delete.

["Nicholas A. Bellinger" <nab@linux-iscsi.org>]

Hi Joe + Himanshu,

Thanks for backporting this patch to apply to v4.10.y.

I haven't seen it queued to v4.9.y yet though, would you be so kind to
send out a v4.9.y backport as well to Greg-KH + stable team so it can be
picked up for earlier stable versions too..?

Thank you,

On Thu, 2017-03-30 at 12:00 +0200, Greg Kroah-Hartman wrote:
> 4.10-stable review patch.  If anyone has any objections, please let me know.
> 
> ------------------
> 
> From: Joe Carnuccio <joe.carnuccio@cavium.com>
> 
> commit c4a9b538ab2a109c5f9798bea1f8f4bf93aadfb9 upstream.
> 
> Signed-off-by: Joe Carnuccio <joe.carnuccio@cavium.com>
> Signed-off-by: Himanshu Madhani <himanshu.madhani@cavium.com>
> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> 
> ---
>  drivers/scsi/qla2xxx/qla_attr.c |    4 +---
>  drivers/scsi/qla2xxx/qla_def.h  |    6 +++++-
>  drivers/scsi/qla2xxx/qla_init.c |    1 +
>  drivers/scsi/qla2xxx/qla_mid.c  |   14 ++++++++------
>  drivers/scsi/qla2xxx/qla_os.c   |    1 +
>  5 files changed, 16 insertions(+), 10 deletions(-)
> 
> --- a/drivers/scsi/qla2xxx/qla_attr.c
> +++ b/drivers/scsi/qla2xxx/qla_attr.c
> @@ -2154,8 +2154,6 @@ qla24xx_vport_delete(struct fc_vport *fc
>  		    "Timer for the VP[%d] has stopped\n", vha->vp_idx);
>  	}
>  
> -	BUG_ON(atomic_read(&vha->vref_count));
> -
>  	qla2x00_free_fcports(vha);
>  
>  	mutex_lock(&ha->vport_lock);
> @@ -2163,7 +2161,7 @@ qla24xx_vport_delete(struct fc_vport *fc
>  	clear_bit(vha->vp_idx, ha->vp_idx_map);
>  	mutex_unlock(&ha->vport_lock);
>  
> -	if (vha->qpair->vp_idx == vha->vp_idx) {
> +	if (vha->qpair && vha->qpair->vp_idx == vha->vp_idx) {
>  		if (qla2xxx_delete_qpair(vha, vha->qpair) != QLA_SUCCESS)
>  			ql_log(ql_log_warn, vha, 0x7087,
>  			    "Queue Pair delete failed.\n");
> --- a/drivers/scsi/qla2xxx/qla_def.h
> +++ b/drivers/scsi/qla2xxx/qla_def.h
> @@ -3788,6 +3788,7 @@ typedef struct scsi_qla_host {
>  	struct qla8044_reset_template reset_tmplt;
>  	struct qla_tgt_counters tgt_counters;
>  	uint16_t	bbcr;
> +	wait_queue_head_t vref_waitq;
>  } scsi_qla_host_t;
>  
>  struct qla27xx_image_status {
> @@ -3843,14 +3844,17 @@ struct qla2_sgx {
>  	mb();						\
>  	if (__vha->flags.delete_progress) {		\
>  		atomic_dec(&__vha->vref_count);		\
> +		wake_up(&__vha->vref_waitq);		\
>  		__bail = 1;				\
>  	} else {					\
>  		__bail = 0;				\
>  	}						\
>  } while (0)
>  
> -#define QLA_VHA_MARK_NOT_BUSY(__vha)			\
> +#define QLA_VHA_MARK_NOT_BUSY(__vha) do {		\
>  	atomic_dec(&__vha->vref_count);			\
> +	wake_up(&__vha->vref_waitq);			\
> +} while (0)						\
>  
>  #define QLA_QPAIR_MARK_BUSY(__qpair, __bail) do {	\
>  	atomic_inc(&__qpair->ref_count);		\
> --- a/drivers/scsi/qla2xxx/qla_init.c
> +++ b/drivers/scsi/qla2xxx/qla_init.c
> @@ -4352,6 +4352,7 @@ qla2x00_update_fcports(scsi_qla_host_t *
>  			}
>  		}
>  		atomic_dec(&vha->vref_count);
> +		wake_up(&vha->vref_waitq);
>  	}
>  	spin_unlock_irqrestore(&ha->vport_slock, flags);
>  }
> --- a/drivers/scsi/qla2xxx/qla_mid.c
> +++ b/drivers/scsi/qla2xxx/qla_mid.c
> @@ -74,13 +74,14 @@ qla24xx_deallocate_vp_id(scsi_qla_host_t
>  	 * ensures no active vp_list traversal while the vport is removed
>  	 * from the queue)
>  	 */
> -	spin_lock_irqsave(&ha->vport_slock, flags);
> -	while (atomic_read(&vha->vref_count)) {
> -		spin_unlock_irqrestore(&ha->vport_slock, flags);
> -
> -		msleep(500);
> +	wait_event_timeout(vha->vref_waitq, atomic_read(&vha->vref_count),
> +	    10*HZ);
>  
> -		spin_lock_irqsave(&ha->vport_slock, flags);
> +	spin_lock_irqsave(&ha->vport_slock, flags);
> +	if (atomic_read(&vha->vref_count)) {
> +		ql_dbg(ql_dbg_vport, vha, 0xfffa,
> +		    "vha->vref_count=%u timeout\n", vha->vref_count.counter);
> +		vha->vref_count = (atomic_t)ATOMIC_INIT(0);
>  	}
>  	list_del(&vha->list);
>  	qlt_update_vp_map(vha, RESET_VP_IDX);
> @@ -269,6 +270,7 @@ qla2x00_alert_all_vps(struct rsp_que *rs
>  
>  			spin_lock_irqsave(&ha->vport_slock, flags);
>  			atomic_dec(&vha->vref_count);
> +			wake_up(&vha->vref_waitq);
>  		}
>  		i++;
>  	}
> --- a/drivers/scsi/qla2xxx/qla_os.c
> +++ b/drivers/scsi/qla2xxx/qla_os.c
> @@ -4215,6 +4215,7 @@ struct scsi_qla_host *qla2x00_create_hos
>  
>  	spin_lock_init(&vha->work_lock);
>  	spin_lock_init(&vha->cmd_list_lock);
> +	init_waitqueue_head(&vha->vref_waitq);
>  
>  	sprintf(vha->host_str, "%s_%ld", QLA2XXX_DRIVER_NAME, vha->host_no);
>  	ql_dbg(ql_dbg_init, vha, 0x0041,
> 
>