libata: add whitelist for devices with known good pata-sata bridges

libata currently imposes a UDMA5 max transfer rate and 200 sector max
transfer size for SATA devices that sit behind a pata-sata bridge. Lots
of devices have known good bridges that don't need this limit applied.
The MTRON SSD disks are such devices. Transfer rates are increased by
20-30% with the restriction removed.

So add a "blacklist" entry for the MTRON devices, with a flag indicating
that the bridge is known good.

Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/include/linux/libata.h b/include/linux/libata.h
index 507f53ef8038..f5441edee55f 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -372,6 +372,7 @@ enum {
         ATA_HORKAGE_IPM         = (1 << 7),     /* Link PM problems */
         ATA_HORKAGE_IVB         = (1 << 8),     /* cbl det validity bit bugs */
         ATA_HORKAGE_STUCK_ERR   = (1 << 9),     /* stuck ERR on next PACKET */
+        ATA_HORKAGE_BRIDGE_OK   = (1 << 10),    /* no bridge limits */
 
          /* DMA mask for user DMA control: User visible values; DO NOT
             renumber */