From 7e443312403ad1ff40ef3177590e96d1fe747c79 Mon Sep 17 00:00:00 2001
From: Alan Stern <stern@rowland.harvard.edu>
Date: Tue, 7 Sep 2010 11:27:52 -0400
Subject: [PATCH] [SCSI] sd: fix medium-removal bug

Commit 409f3499a2cfcd1e9c2857c53af7fcce069f027f (scsi/sd: remove big
kernel lock) introduced a bug in the sd_release routine.  Medium
removal should be allowed when the number of open file references
drops to 0, not when it becomes non-zero.

This patch (as1414) adjusts the test to fix the bug.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
---
 drivers/scsi/sd.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index cd71f46a3d47..ffa0689ee840 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -870,7 +870,7 @@ static int sd_release(struct gendisk *disk, fmode_t mode)
 
 	SCSI_LOG_HLQUEUE(3, sd_printk(KERN_INFO, sdkp, "sd_release\n"));
 
-	if (atomic_dec_return(&sdkp->openers) && sdev->removable) {
+	if (atomic_dec_return(&sdkp->openers) == 0 && sdev->removable) {
 		if (scsi_block_when_processing_errors(sdev))
 			scsi_set_medium_removal(sdev, SCSI_REMOVAL_ALLOW);
 	}
-- 
2.20.1