4.4-stable review patch. If anyone has any objections, please let me know.
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From: Himanshu Madhani himanshu.madhani@cavium.com
commit 413c2f33489b134e3cc65d9c3ff7861e8fdfe899 upstream.
This patch prevents driver from setting lower default speed of 1 GB/sec, if the switch does not support Get Port Speed Capabilities (GPSC) command. Setting this default speed results into much lower write performance for large sequential WRITE. This patch modifies driver to check for gpsc_supported flags and prevents driver from issuing MBC_SET_PORT_PARAM (001Ah) to set default speed of 1 GB/sec. If driver does not send this mailbox command, firmware assumes maximum supported link speed and will operate at the max speed.
Cc: stable@vger.kernel.org Signed-off-by: Himanshu Madhani himanshu.madhani@cavium.com Reported-by: Eda Zhou ezhou@redhat.com Reviewed-by: Ewan D. Milne emilne@redhat.com Tested-by: Ewan D. Milne emilne@redhat.com Signed-off-by: Martin K. Petersen martin.petersen@oracle.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/scsi/qla2xxx/qla_init.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
--- a/drivers/scsi/qla2xxx/qla_init.c +++ b/drivers/scsi/qla2xxx/qla_init.c @@ -3261,7 +3261,8 @@ qla2x00_iidma_fcport(scsi_qla_host_t *vh return;
if (fcport->fp_speed == PORT_SPEED_UNKNOWN || - fcport->fp_speed > ha->link_data_rate) + fcport->fp_speed > ha->link_data_rate || + !ha->flags.gpsc_supported) return;
rval = qla2x00_set_idma_speed(vha, fcport->loop_id, fcport->fp_speed,