sata_mv delayed eh handling
Introduce a new "delayed error handling" mechanism in sata_mv,
to enable us to eventually deal with multiple simultaneous NCQ
failures on a single host link when a PM is present.
This involves a port flag (MV_PP_FLAG_DELAYED_EH) to prevent new
commands being queued, and a pmp bitmap to indicate which pmp links
had NCQ errors.
The new mv_pmp_error_handler() uses those values to invoke
ata_eh_analyze_ncq_error() on each failed link, prior to freezing
the port and passing control to sata_pmp_error_handler().
This is based upon a strategy suggested by Tejun.
For now, we just implement the delayed mechanism.
The next patch in this series will add the multiple-NCQ EH code
to take advantage of it.
Signed-off-by: Mark Lord <mlord@pobox.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
diff --git a/drivers/ata/sata_mv.c b/drivers/ata/sata_mv.c
index 803578e..1991eb2 100644
--- a/drivers/ata/sata_mv.c
+++ b/drivers/ata/sata_mv.c
@@ -367,6 +367,7 @@
MV_PP_FLAG_EDMA_EN = (1 << 0), /* is EDMA engine enabled? */
MV_PP_FLAG_NCQ_EN = (1 << 1), /* is EDMA set up for NCQ? */
MV_PP_FLAG_FBS_EN = (1 << 2), /* is EDMA set up for FBS? */
+ MV_PP_FLAG_DELAYED_EH = (1 << 3), /* delayed dev err handling */
};
#define IS_GEN_I(hpriv) ((hpriv)->hp_flags & MV_HP_GEN_I)
@@ -447,6 +448,7 @@
unsigned int resp_idx;
u32 pp_flags;
+ unsigned int delayed_eh_pmp_map;
};
struct mv_port_signal {
@@ -542,6 +544,7 @@
unsigned long deadline);
static int mv_softreset(struct ata_link *link, unsigned int *class,
unsigned long deadline);
+static void mv_pmp_error_handler(struct ata_port *ap);
/* .sg_tablesize is (MV_MAX_SG_CT / 2) in the structures below
* because we have to allow room for worst case splitting of
@@ -589,7 +592,7 @@
.pmp_hardreset = mv_pmp_hardreset,
.pmp_softreset = mv_softreset,
.softreset = mv_softreset,
- .error_handler = sata_pmp_error_handler,
+ .error_handler = mv_pmp_error_handler,
};
static struct ata_port_operations mv_iie_ops = {
@@ -1098,6 +1101,12 @@
struct mv_port_priv *pp = ap->private_data;
/*
+ * Don't allow new commands if we're in a delayed EH state
+ * for NCQ and/or FIS-based switching.
+ */
+ if (pp->pp_flags & MV_PP_FLAG_DELAYED_EH)
+ return ATA_DEFER_PORT;
+ /*
* If the port is completely idle, then allow the new qc.
*/
if (ap->nr_active_links == 0)
@@ -1591,6 +1600,33 @@
return qc;
}
+static void mv_pmp_error_handler(struct ata_port *ap)
+{
+ unsigned int pmp, pmp_map;
+ struct mv_port_priv *pp = ap->private_data;
+
+ if (pp->pp_flags & MV_PP_FLAG_DELAYED_EH) {
+ /*
+ * Perform NCQ error analysis on failed PMPs
+ * before we freeze the port entirely.
+ *
+ * The failed PMPs are marked earlier by mv_pmp_eh_prep().
+ */
+ pmp_map = pp->delayed_eh_pmp_map;
+ pp->pp_flags &= ~MV_PP_FLAG_DELAYED_EH;
+ for (pmp = 0; pmp_map != 0; pmp++) {
+ unsigned int this_pmp = (1 << pmp);
+ if (pmp_map & this_pmp) {
+ struct ata_link *link = &ap->pmp_link[pmp];
+ pmp_map &= ~this_pmp;
+ ata_eh_analyze_ncq_error(link);
+ }
+ }
+ ata_port_freeze(ap);
+ }
+ sata_pmp_error_handler(ap);
+}
+
static void mv_unexpected_intr(struct ata_port *ap, int edma_was_enabled)
{
struct ata_eh_info *ehi = &ap->link.eh_info;