[PATCH] Add pgprot_noncached() to UIO mmap code

[Hans J. Koch]

From: Jean-Samuel Chenard <jsamch@xxxxxxxxx>
To: Greg KH <greg@xxxxxxxxx>
Cc: Hans J Koch <hjk@xxxxxxxxxxxxx>, linux-kernel@xxxxxxxxxxxxxxx,
 Juergen Beisert <juergen127@xxxxxxxxxxxxxx>
Date: Fri, 14 Mar 2008 11:19:49 +0100
Subject: Add pgprot_noncached() to UIO mmap code

Mapping of physical memory in UIO needs pgprot_noncached() to ensure
that IO memory is not cached. Without pgprot_noncached(), it (accidentally)
works on x86 and arm, but fails on PPC.

Signed-off-by: Jean-Samuel Chenard <jsamch@xxxxxxxxx>
Signed-off-by: Hans J Koch <hjk@xxxxxxxxxxxxx>

---
 drivers/uio/uio.c |    2 ++
 1 file changed, 2 insertions(+)

Index: linux-2.6.25-rc/drivers/uio/uio.c
===================================================================
--- linux-2.6.25-rc.orig/drivers/uio/uio.c	2008-03-14 11:00:59.000000000 +0100
+++ linux-2.6.25-rc/drivers/uio/uio.c	2008-03-14 11:03:13.000000000 +0100
@@ -470,6 +470,8 @@
 
 	vma->vm_flags |= VM_IO | VM_RESERVED;
 
+	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
+
 	return remap_pfn_range(vma,
 			       vma->vm_start,
 			       idev->info->mem[mi].addr >> PAGE_SHIFT,
--
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