From 83e4d2e77251ae4876f89ff009a9c0fd8627cc42 Mon Sep 17 00:00:00 2001
From: Tejun Heo <tj@kernel.org>
Date: Thu, 29 Jan 2009 20:31:32 +0900
Subject: [PATCH] --- yaml --- r: 130813 b: refs/heads/master c:
 99cf610aa4840d822cdc67d194b23b55010ca9bd h: refs/heads/master i:   130811:
 f6cee8138986f164aaa0b7557cc7376362fb40d9 v: v3

---
 [refs]                          |  2 +-
 trunk/drivers/ata/libata-core.c |  4 ++--
 trunk/drivers/ata/libata-eh.c   |  7 +++++++
 trunk/include/linux/libata.h    | 18 ++++++++++--------
 4 files changed, 20 insertions(+), 11 deletions(-)

diff --git a/[refs] b/[refs]
index fa692dd31b5d..1dabdfcadaee 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 9913ff8abf1c70a8d52560dc931e1901d025ad27
+refs/heads/master: 99cf610aa4840d822cdc67d194b23b55010ca9bd
diff --git a/trunk/drivers/ata/libata-core.c b/trunk/drivers/ata/libata-core.c
index d006e5c4768c..564c03c4ebb3 100644
--- a/trunk/drivers/ata/libata-core.c
+++ b/trunk/drivers/ata/libata-core.c
@@ -5404,8 +5404,8 @@ void ata_dev_init(struct ata_device *dev)
 	dev->horkage = 0;
 	spin_unlock_irqrestore(ap->lock, flags);
 
-	memset((void *)dev + ATA_DEVICE_CLEAR_OFFSET, 0,
-	       sizeof(*dev) - ATA_DEVICE_CLEAR_OFFSET);
+	memset((void *)dev + ATA_DEVICE_CLEAR_BEGIN, 0,
+	       ATA_DEVICE_CLEAR_END - ATA_DEVICE_CLEAR_BEGIN);
 	dev->pio_mask = UINT_MAX;
 	dev->mwdma_mask = UINT_MAX;
 	dev->udma_mask = UINT_MAX;
diff --git a/trunk/drivers/ata/libata-eh.c b/trunk/drivers/ata/libata-eh.c
index aafe82bf5e2e..90092c1aae53 100644
--- a/trunk/drivers/ata/libata-eh.c
+++ b/trunk/drivers/ata/libata-eh.c
@@ -1194,6 +1194,11 @@ void ata_dev_disable(struct ata_device *dev)
 	ata_acpi_on_disable(dev);
 	ata_down_xfermask_limit(dev, ATA_DNXFER_FORCE_PIO0 | ATA_DNXFER_QUIET);
 	dev->class++;
+
+	/* From now till the next successful probe, ering is used to
+	 * track probe failures.  Clear accumulated device error info.
+	 */
+	ata_ering_clear(&dev->ering);
 }
 
 /**
@@ -2765,6 +2770,8 @@ static int ata_eh_revalidate_and_attach(struct ata_link *link,
 						     readid_flags, dev->id);
 			switch (rc) {
 			case 0:
+				/* clear error info accumulated during probe */
+				ata_ering_clear(&dev->ering);
 				new_mask |= 1 << dev->devno;
 				break;
 			case -ENOENT:
diff --git a/trunk/include/linux/libata.h b/trunk/include/linux/libata.h
index bca3ba25f52a..9dcefee5843c 100644
--- a/trunk/include/linux/libata.h
+++ b/trunk/include/linux/libata.h
@@ -580,7 +580,7 @@ struct ata_device {
 	acpi_handle		acpi_handle;
 	union acpi_object	*gtf_cache;
 #endif
-	/* n_sector is used as CLEAR_OFFSET, read comment above CLEAR_OFFSET */
+	/* n_sector is CLEAR_BEGIN, read comment above CLEAR_BEGIN */
 	u64			n_sectors;	/* size of device, if ATA */
 	unsigned int		class;		/* ATA_DEV_xxx */
 	unsigned long		unpark_deadline;
@@ -605,20 +605,22 @@ struct ata_device {
 	u16			heads;		/* Number of heads */
 	u16			sectors;	/* Number of sectors per track */
 
-	/* error history */
-	int			spdn_cnt;
-	struct ata_ering	ering;
-
 	union {
 		u16		id[ATA_ID_WORDS]; /* IDENTIFY xxx DEVICE data */
 		u32		gscr[SATA_PMP_GSCR_DWORDS]; /* PMP GSCR block */
 	};
+
+	/* error history */
+	int			spdn_cnt;
+	/* ering is CLEAR_END, read comment above CLEAR_END */
+	struct ata_ering	ering;
 };
 
-/* Offset into struct ata_device.  Fields above it are maintained
- * acress device init.  Fields below are zeroed.
+/* Fields between ATA_DEVICE_CLEAR_BEGIN and ATA_DEVICE_CLEAR_END are
+ * cleared to zero on ata_dev_init().
  */
-#define ATA_DEVICE_CLEAR_OFFSET		offsetof(struct ata_device, n_sectors)
+#define ATA_DEVICE_CLEAR_BEGIN		offsetof(struct ata_device, n_sectors)
+#define ATA_DEVICE_CLEAR_END		offsetof(struct ata_device, ering)
 
 struct ata_eh_info {
 	struct ata_device	*dev;		/* offending device */