sata_nv: complain on spurious completion notifiers

Recently Tejun wrote a patch to ahci.c to make it raise a HSM violation
if the drive attempted to complete a tag that wasn't outstanding. We could
run into the same problem with sata_nv ADMA. This adds code to raise a HSM
violation error if the controller gives us a notifier tag that isn't
outstanding, since the drive may be issuing spurious completions.

Signed-off-by: Robert Hancock <hancockr@shaw.ca>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

diff --git a/drivers/ata/sata_nv.c b/drivers/ata/sata_nv.c
index 4d9357c..783281e 100644 (file)
--- a/drivers/ata/sata_nv.c
+++ b/drivers/ata/sata_nv.c
@@ -740,6 +740,17 @@ static int nv_adma_check_cpb(struct ata_port *ap, int cpb_num, int force_err)
                        DPRINTK("Completing qc from tag %d with err_mask %u\n",cpb_num,
                                qc->err_mask);
                        ata_qc_complete(qc);
+               } else {
+                       struct ata_eh_info *ehi = &ap->eh_info;
+                       /* Notifier bits set without a command may indicate the drive
+                          is misbehaving. Raise host state machine violation on this
+                          condition. */
+                       ata_port_printk(ap, KERN_ERR, "notifier for tag %d with no command?\n",
+                               cpb_num);
+                       ehi->err_mask |= AC_ERR_HSM;
+                       ehi->action |= ATA_EH_SOFTRESET;
+                       ata_port_freeze(ap);
+                       return 1;
                }
        }
        return 0;