megaraid_sas: Add an i/o barrier

[ Upstream commit b99dbe56d511eb07de33bfa1b99ac5a6ff76ae08 ]

A barrier should be added to ensure proper ordering of memory mapped
writes.

Signed-off-by: Tomas Henzl <thenzl@redhat.com>
Reviewed-by: Kashyap Desai <kashyap.desai@broadcom.com>
Acked-by: Kashyap Desai <kashyap.desai@broadcom.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/scsi/megaraid/megaraid_sas_base.c b/drivers/scsi/megaraid/megaraid_sas_base.c
index 6dbaa3c38d1efd411a097f315ecf93fab9ed9eb1..3f8d357b1bac9f93c2128254b11a677638c105e9 100644 (file)
--- a/drivers/scsi/megaraid/megaraid_sas_base.c
+++ b/drivers/scsi/megaraid/megaraid_sas_base.c
@@ -735,6 +735,7 @@ megasas_fire_cmd_skinny(struct megasas_instance *instance,
               &(regs)->inbound_high_queue_port);
        writel((lower_32_bits(frame_phys_addr) | (frame_count<<1))|1,
               &(regs)->inbound_low_queue_port);
+       mmiowb();
        spin_unlock_irqrestore(&instance->hba_lock, flags);
 }
 

diff --git a/drivers/scsi/megaraid/megaraid_sas_fusion.c b/drivers/scsi/megaraid/megaraid_sas_fusion.c
index 4f391e747be2bc632e11d85f39aed74605a1f709..021b994fdae8d08e95df2dac143125131aca32ff 100644 (file)
--- a/drivers/scsi/megaraid/megaraid_sas_fusion.c
+++ b/drivers/scsi/megaraid/megaraid_sas_fusion.c
@@ -201,6 +201,7 @@ megasas_fire_cmd_fusion(struct megasas_instance *instance,
                &instance->reg_set->inbound_low_queue_port);
        writel(le32_to_cpu(req_desc->u.high),
                &instance->reg_set->inbound_high_queue_port);
+       mmiowb();
        spin_unlock_irqrestore(&instance->hba_lock, flags);
 #endif
 }