From: Stanislaw Gruszka <sgruszka@redhat.com>
Date: Thu, 12 Mar 2009 13:09:58 +0100
Subject: [ide] increase timeouts in wait_drive_not_busy
Message-id: 20090312130958.0cdff6a2@dhcp-lab-109.englab.brq.redhat.com
O-Subject: [RHEL5.4 PATCH] BZ464039: Timeouts in wait_drive_not_busy with TEAC DV-W28ECW and similar
Bugzilla: 464039
RH-Acked-by: Prarit Bhargava <prarit@redhat.com>
RH-Acked-by: Peter Martuccelli <peterm@redhat.com>
RH-Acked-by: Michal Schmidt <mschmidt@redhat.com>
RH-Acked-by: Tomas Henzl <thenzl@redhat.com>

BZ#464039
=========
https://bugzilla.redhat.com/show_bug.cgi?id=464039

Description:
============
Some TEAC drives take a long time to return to non-Busy status
following an IDENTIFY command (>=6ms), causing following messages to be
logged:

08:20:36 hex kernel: hda: irq timeout: status=0xd0 { Busy }
08:20:36 hex kernel: hda: irq timeout: error=0x00
08:20:36 hex kernel: hda: ATAPI reset complete
08:20:36 hex kernel: VFS: busy inodes on changed media

Patch increase timeout to 10ms and change the logic a bit
to fix never called printk statement.

kABI Status:
============
No symbols were harmed.

Brew:
====
https://brewweb.devel.redhat.com/taskinfo?taskID=1722443

Upstream Status:
===============
This patch is a backport of changes from:

b42fa133110fa952299fa76cbe91226c14838261
f54feafa6d47d0aa1a96adefdc763b708b02f94f

Test Status:
============
That the patch fix bug was already tested by IT:
https://enterprise.redhat.com/issue-tracker/?module=issues&action=view&tid=197920

I tested it against other breakage, just reading
cat /proc/ide/driver/identify and doing other
operations on cd.

diff --git a/drivers/ide/ide-taskfile.c b/drivers/ide/ide-taskfile.c
index 97a9244..480bf23 100644
--- a/drivers/ide/ide-taskfile.c
+++ b/drivers/ide/ide-taskfile.c
@@ -238,18 +238,21 @@ EXPORT_SYMBOL(task_no_data_intr);
 static u8 wait_drive_not_busy(ide_drive_t *drive)
 {
 	ide_hwif_t *hwif = HWIF(drive);
-	int retries = 100;
+	int retries;
 	u8 stat;
 
 	/*
-	 * Last sector was transfered, wait until drive is ready.
-	 * This can take up to 10 usec, but we will wait max 1 ms
-	 * (drive_cmd_intr() waits that long).
+	 * Last sector was transfered, wait until device is ready.  This can
+	 * take up to 6 ms on some ATAPI devices, so we will wait max 10 ms.
 	 */
-	while (((stat = hwif->INB(IDE_STATUS_REG)) & BUSY_STAT) && retries--)
-		udelay(10);
+	for (retries = 0; retries < 1000; retries++) {
+		if ((stat = hwif->INB(IDE_STATUS_REG)) & BUSY_STAT)
+			udelay(10);
+		else
+			break;
+	}
 
-	if (!retries)
+	if (stat & BUSY_STAT)
 		printk(KERN_ERR "%s: drive still BUSY!\n", drive->name);
 
 	return stat;