From: Jarod Wilson <jwilson@redhat.com>
Date: Tue, 7 Aug 2007 12:01:31 -0400
Subject: [ia64] ioremap: allow cacheable mmaps of legacy_mem
Message-id: 46B8975B.4070309@redhat.com
O-Subject: [RHEL5.1 PATCH 4/5] ia64: validate and remap mmap requests
Bugzilla: 240006

This is a multi-part message in MIME format.
Allow cacheable mmaps of legacy_mem.

[PATCH] ia64: allow WB /sys/.../legacy_mem mmaps

Allow cacheable mmaps of legacy_mem if WB access is supported for the
region. The "legacy_mem" file often contains a shadow option ROM, and
some versions of X depend on this.

Tim Yamin <plasm@roo.me.uk> reported that this change fixes X on a Dell
PowerEdge 3250.

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>

--
Jarod Wilson
jwilson@redhat.com

[PATCH] ia64: allow WB /sys/.../legacy_mem mmaps

Allow cacheable mmaps of legacy_mem if WB access is supported for the region.
The "legacy_mem" file often contains a shadow option ROM, and some versions of
X depend on this.

Tim Yamin <plasm@roo.me.uk> reported that this change fixes X on a Dell
PowerEdge 3250.

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>

Acked-by: Steven Rostedt <srostedt@redhat.com>

diff --git a/arch/ia64/pci/pci.c b/arch/ia64/pci/pci.c
index 0d38f22..bdb3bfa 100644
--- a/arch/ia64/pci/pci.c
+++ b/arch/ia64/pci/pci.c
@@ -665,8 +665,6 @@ pci_mmap_legacy_page_range(struct pci_bus *bus, struct vm_area_struct *vma)
 		return -EINVAL;
 	prot = phys_mem_access_prot(NULL, vma->vm_pgoff, size,
 				    vma->vm_page_prot);
-	if (pgprot_val(prot) != pgprot_val(pgprot_noncached(vma->vm_page_prot)))
-		return -EINVAL;
 
 	addr = pci_get_legacy_mem(bus);
 	if (IS_ERR(addr))