From e198076542a22ce7773184e3618440b29bf64d83 Mon Sep 17 00:00:00 2001
From: Albert Lee <albertcc@tw.ibm.com>
Date: Sat, 25 Mar 2006 18:11:12 +0800
Subject: [PATCH] --- yaml --- r: 29407 b: refs/heads/master c:
 71601958f73b952281f2b02e16d1f11c99ee0a8b h: refs/heads/master i:   29405:
 c7f30fd7b6267b1d8def8a6cb491775a29d5c5a0   29403:
 629503b02037ef3edc4ba92963c2817d951d91ef   29399:
 764b7fb09b5ec7ef5cd9e4a0e3bf120074b95577   29391:
 7499ce4dde889ee0fbc619d0673deab29e1ce6ba   29375:
 53a0d5885d46fde7511d5319eff94cc62cd633a7 v: v3

---
 [refs]                           |  2 +-
 trunk/drivers/scsi/libata-core.c | 44 +++++++++++++++++++++++++++-----
 2 files changed, 39 insertions(+), 7 deletions(-)

diff --git a/[refs] b/[refs]
index bf9cb1d4d81f..d245216394f4 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 999bb6f4260f9499fdeab3f8fdcd8b9013eca39e
+refs/heads/master: 71601958f73b952281f2b02e16d1f11c99ee0a8b
diff --git a/trunk/drivers/scsi/libata-core.c b/trunk/drivers/scsi/libata-core.c
index d68f5d5b423a..59cb12993f95 100644
--- a/trunk/drivers/scsi/libata-core.c
+++ b/trunk/drivers/scsi/libata-core.c
@@ -3587,12 +3587,6 @@ static int ata_hsm_move(struct ata_port *ap, struct ata_queued_cmd *qc,
 	 */
 	WARN_ON(in_wq != ata_hsm_ok_in_wq(ap, qc));
 
-	/* check error */
-	if (unlikely(status & (ATA_ERR | ATA_DF))) {
-		qc->err_mask |= AC_ERR_DEV;
-		ap->hsm_task_state = HSM_ST_ERR;
-	}
-
 fsm_start:
 	DPRINTK("ata%u: protocol %d task_state %d (dev_stat 0x%X)\n",
 		ap->id, qc->tf.protocol, ap->hsm_task_state, status);
@@ -3615,6 +3609,17 @@ static int ata_hsm_move(struct ata_port *ap, struct ata_queued_cmd *qc,
 			goto fsm_start;
 		}
 
+		/* Device should not ask for data transfer (DRQ=1)
+		 * when it finds something wrong.
+		 * Anyway, we respect DRQ here and let HSM go on
+		 * without changing hsm_task_state to HSM_ST_ERR.
+		 */
+		if (unlikely(status & (ATA_ERR | ATA_DF))) {
+			printk(KERN_WARNING "ata%d: DRQ=1 with device error, dev_stat 0x%X\n",
+			       ap->id, status);
+			qc->err_mask |= AC_ERR_DEV;
+		}
+
 		/* Send the CDB (atapi) or the first data block (ata pio out).
 		 * During the state transition, interrupt handler shouldn't
 		 * be invoked before the data transfer is complete and
@@ -3657,6 +3662,17 @@ static int ata_hsm_move(struct ata_port *ap, struct ata_queued_cmd *qc,
 				goto fsm_start;
 			}
 
+			/* Device should not ask for data transfer (DRQ=1)
+			 * when it finds something wrong.
+			 * Anyway, we respect DRQ here and let HSM go on
+			 * without changing hsm_task_state to HSM_ST_ERR.
+			 */
+			if (unlikely(status & (ATA_ERR | ATA_DF))) {
+				printk(KERN_WARNING "ata%d: DRQ=1 with device error, dev_stat 0x%X\n",
+				       ap->id, status);
+				qc->err_mask |= AC_ERR_DEV;
+			}
+
 			atapi_pio_bytes(qc);
 
 			if (unlikely(ap->hsm_task_state == HSM_ST_ERR))
@@ -3672,6 +3688,22 @@ static int ata_hsm_move(struct ata_port *ap, struct ata_queued_cmd *qc,
 				goto fsm_start;
 			}
 
+			/* Some devices may ask for data transfer (DRQ=1)
+			 * alone with ERR=1 for PIO reads.
+			 * We respect DRQ here and let HSM go on without
+			 * changing hsm_task_state to HSM_ST_ERR.
+			 */
+			if (unlikely(status & (ATA_ERR | ATA_DF))) {
+				/* For writes, ERR=1 DRQ=1 doesn't make
+				 * sense since the data block has been
+				 * transferred to the device.
+				 */
+				WARN_ON(qc->tf.flags & ATA_TFLAG_WRITE);
+
+				/* data might be corrputed */
+				qc->err_mask |= AC_ERR_DEV;
+			}
+
 			ata_pio_sectors(qc);
 
 			if (ap->hsm_task_state == HSM_ST_LAST &&