libata: implement ATA_DFLAG_DUBIOUS_XFER

ATA_DFLAG_DUBIOUS_XFER is set whenever data transfer speed or method
changes and gets cleared when data transfer command succeeds in the
newly configured transfer mode.

This will be used to improve speed down logic.

Signed-off-by: Tejun Heo <htejun@gmail.com<
Signed-off-by: Jeff Garzik <jeff@garzik.org>

1 files changed, 3 insertions, 0 deletions

diff --git a/include/linux/libata.h b/include/linux/libata.h
index 74f1255e2524..131fb6625e14 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -143,6 +143,7 @@ enum {
         ATA_DFLAG_NCQ_OFF       = (1 << 13), /* device limited to non-NCQ mode */
         ATA_DFLAG_SPUNDOWN      = (1 << 14), /* XXX: for spindown_compat */
         ATA_DFLAG_SLEEPING      = (1 << 15), /* device is sleeping */
+        ATA_DFLAG_DUBIOUS_XFER  = (1 << 16), /* data transfer not verified */
         ATA_DFLAG_INIT_MASK     = (1 << 24) - 1,
 
         ATA_DFLAG_DETACH        = (1 << 24),
@@ -560,6 +561,8 @@ struct ata_eh_context {
         int                     tries[ATA_MAX_DEVICES];
         unsigned int            classes[ATA_MAX_DEVICES];
         unsigned int            did_probe_mask;
+        unsigned int            saved_ncq_enabled;
+        u8                      saved_xfer_mode[ATA_MAX_DEVICES];
 };
 
 struct ata_acpi_drive