Patch "s390/dcssblk: fix device size calculation in dcssblk_direct_access()" has been added to the 4.4-stable tree

Patch "s390/dcssblk: fix device size calculation in dcssblk_direct_access()" has been added to the 4.4-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    s390/dcssblk: fix device size calculation in dcssblk_direct_access()

to the 4.4-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     s390-dcssblk-fix-device-size-calculation-in-dcssblk_direct_access.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From a63f53e34db8b49675448d03ae324f6c5bc04fe6 Mon Sep 17 00:00:00 2001
From: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Date: Mon, 30 Jan 2017 15:52:14 +0100
Subject: s390/dcssblk: fix device size calculation in dcssblk_direct_access()

From: Gerald Schaefer <gerald.schaefer@de.ibm.com>

commit a63f53e34db8b49675448d03ae324f6c5bc04fe6 upstream.

Since commit dd22f551 "block: Change direct_access calling convention",
the device size calculation in dcssblk_direct_access() is off-by-one.
This results in bdev_direct_access() always returning -ENXIO because the
returned value is not page aligned.

Fix this by adding 1 to the dev_sz calculation.

Fixes: dd22f551 ("block: Change direct_access calling convention")
Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/s390/block/dcssblk.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/s390/block/dcssblk.c
+++ b/drivers/s390/block/dcssblk.c
@@ -892,7 +892,7 @@ dcssblk_direct_access (struct block_devi
 	dev_info = bdev->bd_disk->private_data;
 	if (!dev_info)
 		return -ENODEV;
-	dev_sz = dev_info->end - dev_info->start;
+	dev_sz = dev_info->end - dev_info->start + 1;
 	offset = secnum * 512;
 	addr = (void *) (dev_info->start + offset);
 	*pfn = virt_to_phys(addr) >> PAGE_SHIFT;


Patches currently in stable-queue which might be from gerald.schaefer@de.ibm.com are

queue-4.4/s390-dcssblk-fix-device-size-calculation-in-dcssblk_direct_access.patch