libata: fix ata_scmd_need_defer()

Fix ata_scmd_need_defer() such that... * whether NCQ is used or not is exactly determined using the same criteria as the issue path. * defer-check is performed in all cases. This fixes race condition where turning off NCQ on the fly causes non-NCQ commands sneak into NCQ phase. Signed-off-by: Tejun Heo <[email protected]> Signed-off-by: Jeff Garzik <[email protected]>
goeke · Feb 21, 2007 · fcf1bf1 · fcf1bf1
1 parent 6d1245b
commit fcf1bf1
Showing 1 changed file with 2 additions and 4 deletions.
diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c
@@ -1496,11 +1496,9 @@ static void ata_scsi_qc_complete(struct ata_queued_cmd *qc)
 static int ata_scmd_need_defer(struct ata_device *dev, int is_io)
 {
 	struct ata_port *ap = dev->ap;
+	int is_ncq = is_io && ata_ncq_enabled(dev);
 
-	if (!(dev->flags & ATA_DFLAG_NCQ))
-		return 0;
-
-	if (is_io) {
+	if (is_ncq) {
 		if (!ata_tag_valid(ap->active_tag))
 			return 0;
 	} else {