From cd7e93afb0edd654fe220261ce9a1597999e3ffb Mon Sep 17 00:00:00 2001
From: Tejun Heo <htejun@gmail.com>
Date: Mon, 15 May 2006 20:58:19 +0900
Subject: [PATCH] --- yaml --- r: 29311 b: refs/heads/master c:
 0c247c559cd70f85ba9f0764ce13ae00e20fcad8 h: refs/heads/master i:   29309:
 64adc489d466daf83baed5e753cc84bc7e637af1   29307:
 f0153d56682e129fec7c625c255ac76683978b5f   29303:
 5467ae4cf77abc8b01e9ca0f419865e06d0777f4   29295:
 6c06e0fbf0f21c97defb9e3c4b1d5714744130c2   29279:
 b8b5e900d86281030d4c58026309693ffe9da65f   29247:
 cbd4c3d71a2c9fda46b91d7ac71a7173282dbc7d   29183:
 abd228295c198bf53d6215ade6d8ea92636507c5 v: v3

---
 [refs]                         |  2 +-
 trunk/drivers/scsi/libata-eh.c | 45 ++++++++++++++++++++++++++++++++++
 trunk/include/linux/libata.h   | 17 +++++++++++++
 3 files changed, 63 insertions(+), 1 deletion(-)

diff --git a/[refs] b/[refs]
index 10e8a36de9ce..824089490d53 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 9be1e979f2e1e57a091a658fa88dac266f9fd6fe
+refs/heads/master: 0c247c559cd70f85ba9f0764ce13ae00e20fcad8
diff --git a/trunk/drivers/scsi/libata-eh.c b/trunk/drivers/scsi/libata-eh.c
index 0803231f6577..71ad18b7cff6 100644
--- a/trunk/drivers/scsi/libata-eh.c
+++ b/trunk/drivers/scsi/libata-eh.c
@@ -46,6 +46,51 @@
 
 static void __ata_port_freeze(struct ata_port *ap);
 
+static void ata_ering_record(struct ata_ering *ering, int is_io,
+			     unsigned int err_mask)
+{
+	struct ata_ering_entry *ent;
+
+	WARN_ON(!err_mask);
+
+	ering->cursor++;
+	ering->cursor %= ATA_ERING_SIZE;
+
+	ent = &ering->ring[ering->cursor];
+	ent->is_io = is_io;
+	ent->err_mask = err_mask;
+	ent->timestamp = get_jiffies_64();
+}
+
+static struct ata_ering_entry * ata_ering_top(struct ata_ering *ering)
+{
+	struct ata_ering_entry *ent = &ering->ring[ering->cursor];
+	if (!ent->err_mask)
+		return NULL;
+	return ent;
+}
+
+static int ata_ering_map(struct ata_ering *ering,
+			 int (*map_fn)(struct ata_ering_entry *, void *),
+			 void *arg)
+{
+	int idx, rc = 0;
+	struct ata_ering_entry *ent;
+
+	idx = ering->cursor;
+	do {
+		ent = &ering->ring[idx];
+		if (!ent->err_mask)
+			break;
+		rc = map_fn(ent, arg);
+		if (rc)
+			break;
+		idx = (idx - 1 + ATA_ERING_SIZE) % ATA_ERING_SIZE;
+	} while (idx != ering->cursor);
+
+	return rc;
+}
+
 /**
  *	ata_scsi_timed_out - SCSI layer time out callback
  *	@cmd: timed out SCSI command
diff --git a/trunk/include/linux/libata.h b/trunk/include/linux/libata.h
index 6fe5ed8eabf5..f5cea13599c3 100644
--- a/trunk/include/linux/libata.h
+++ b/trunk/include/linux/libata.h
@@ -226,6 +226,9 @@ enum {
 	ATA_PORT_PRIMARY	= (1 << 0),
 	ATA_PORT_SECONDARY	= (1 << 1),
 
+	/* ering size */
+	ATA_ERING_SIZE		= 32,
+
 	/* reset / recovery action types */
 	ATA_EH_REVALIDATE	= (1 << 0),
 	ATA_EH_SOFTRESET	= (1 << 1),
@@ -375,6 +378,17 @@ struct ata_host_stats {
 	unsigned long		rw_reqbuf;
 };
 
+struct ata_ering_entry {
+	int			is_io;
+	unsigned int		err_mask;
+	u64			timestamp;
+};
+
+struct ata_ering {
+	int			cursor;
+	struct ata_ering_entry	ring[ATA_ERING_SIZE];
+};
+
 struct ata_device {
 	struct ata_port		*ap;
 	u64			n_sectors;	/* size of device, if ATA */
@@ -401,6 +415,9 @@ struct ata_device {
 	u16			cylinders;	/* Number of cylinders */
 	u16			heads;		/* Number of heads */
 	u16			sectors;	/* Number of sectors per track */
+
+	/* error history */
+	struct ata_ering	ering;
 };
 
 struct ata_port {