From 03a064b431eb5cb0a91012699ac1e4d6302b327d Mon Sep 17 00:00:00 2001
From: David Woodhouse <dwmw@amazon.co.uk>
Date: Wed, 12 Apr 2017 13:25:53 +0100
Subject: xtensa/PCI: Do not mmap PCI BARs to userspace as write-through
These should be uncached, not write-through.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
---
arch/xtensa/kernel/pci.c | 21 +--------------------
1 file changed, 1 insertion(+), 20 deletions(-)
(limited to 'arch/xtensa')
diff --git a/arch/xtensa/kernel/pci.c b/arch/xtensa/kernel/pci.c
index b848cc3dc913..5b73fc2f076c 100644
--- a/arch/xtensa/kernel/pci.c
+++ b/arch/xtensa/kernel/pci.c
@@ -333,25 +333,6 @@ __pci_mmap_make_offset(struct pci_dev *dev, struct vm_area_struct *vma,
return -EINVAL;
}
-/*
- * Set vm_page_prot of VMA, as appropriate for this architecture, for a pci
- * device mapping.
- */
-static __inline__ void
-__pci_mmap_set_pgprot(struct pci_dev *dev, struct vm_area_struct *vma,
- enum pci_mmap_state mmap_state, int write_combine)
-{
- int prot = pgprot_val(vma->vm_page_prot);
-
- /* Set to write-through */
- prot = (prot & _PAGE_CA_MASK) | _PAGE_CA_WT;
-#if 0
- if (!write_combine)
- prot |= _PAGE_WRITETHRU;
-#endif
- vma->vm_page_prot = __pgprot(prot);
-}
-
/*
* Perform the actual remap of the pages for a PCI device mapping, as
* appropriate for this architecture. The region in the process to map
@@ -372,7 +353,7 @@ int pci_mmap_page_range(struct pci_dev *dev, struct vm_area_struct *vma,
if (ret < 0)
return ret;
- __pci_mmap_set_pgprot(dev, vma, mmap_state, write_combine);
+ vma->vm_page_prot = pgprot_device(vma->vm_page_prot);
ret = io_remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
vma->vm_end - vma->vm_start,vma->vm_page_prot);
--
cgit