From 806a6e7a9904d4a1dfd3fd79d373bf31d71d34cb Mon Sep 17 00:00:00 2001 From: Mark Lord Date: Tue, 21 Mar 2006 21:11:53 -0500 Subject: [libata] sata_mv: off-by-1 fix This patch addresses a number of weird behaviours observed for the sata_mv driver, by fixing an "off by one" bug in processing of the EDMA response queue. Basically, sata_mv was looking in the wrong place for command results, and this produced a lot of unpredictable behaviour. Signed-off-by: Mark Lord Signed-off-by: Jeff Garzik --- drivers/scsi/sata_mv.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) (limited to 'drivers/scsi') diff --git a/drivers/scsi/sata_mv.c b/drivers/scsi/sata_mv.c index e561281967d..eed67ae2dc0 100644 --- a/drivers/scsi/sata_mv.c +++ b/drivers/scsi/sata_mv.c @@ -1263,6 +1263,7 @@ static u8 mv_get_crpb_status(struct ata_port *ap) void __iomem *port_mmio = mv_ap_base(ap); struct mv_port_priv *pp = ap->private_data; u32 out_ptr; + u8 ata_status; out_ptr = readl(port_mmio + EDMA_RSP_Q_OUT_PTR_OFS); @@ -1270,6 +1271,8 @@ static u8 mv_get_crpb_status(struct ata_port *ap) WARN_ON(((out_ptr >> EDMA_RSP_Q_PTR_SHIFT) & MV_MAX_Q_DEPTH_MASK) != pp->rsp_consumer); + ata_status = pp->crpb[pp->rsp_consumer].flags >> CRPB_FLAG_STATUS_SHIFT; + /* increment our consumer index... */ pp->rsp_consumer = mv_inc_q_index(&pp->rsp_consumer); @@ -1284,7 +1287,7 @@ static u8 mv_get_crpb_status(struct ata_port *ap) writelfl(out_ptr, port_mmio + EDMA_RSP_Q_OUT_PTR_OFS); /* Return ATA status register for completed CRPB */ - return (pp->crpb[pp->rsp_consumer].flags >> CRPB_FLAG_STATUS_SHIFT); + return ata_status; } /** -- cgit v1.2.3