[SCSI] libsas, aic94xx: fix dma mapping cockups with ATA

This one was noticed by Gilbert Wu of Adaptec:

The libata core actually does the DMA mapping for you, so there has to
be an exception in the device drivers that *don't* do dma mapping for
ATA commands.  However, since we've already done this, libsas must now
dma map any ATA commands that it wishes to issue ... and yes, this is a
horrible mess.

Additionally, the test in aic94xx for ATA protocols isn't quite right.

Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

1 files changed, 6 insertions, 0 deletions

diff --git a/include/scsi/scsi_transport_sas.h b/include/scsi/scsi_transport_sas.h
index 9aedc19820b0..97eeb5b59ea5 100644
--- a/include/scsi/scsi_transport_sas.h
+++ b/include/scsi/scsi_transport_sas.h
@@ -23,6 +23,12 @@ enum sas_protocol {
         SAS_PROTOCOL_SSP                = 0x08,
 };
 
+static inline int sas_protocol_ata(enum sas_protocol proto)
+{
+        return ((proto & SAS_PROTOCOL_SATA) ||
+                (proto & SAS_PROTOCOL_STP))? 1 : 0;
+}
+
 enum sas_linkrate {
         /* These Values are defined in the SAS standard */
         SAS_LINK_RATE_UNKNOWN = 0,