lkml.org 
[lkml]   [2017]   [Apr]   [12]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH v2 04/27] xtensa: Do not mmap PCI BARs to userspace as write-through
Date
From: David Woodhouse <dwmw@amazon.co.uk>

These should be uncached, not write-through.

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
---
arch/xtensa/kernel/pci.c | 21 +--------------------
1 file changed, 1 insertion(+), 20 deletions(-)

diff --git a/arch/xtensa/kernel/pci.c b/arch/xtensa/kernel/pci.c
index b848cc3..5b73fc2 100644
--- a/arch/xtensa/kernel/pci.c
+++ b/arch/xtensa/kernel/pci.c
@@ -334,25 +334,6 @@ __pci_mmap_make_offset(struct pci_dev *dev, struct vm_area_struct *vma,
}

/*
- * 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
* is described by vm_start and vm_end members of VMA, the base physical
@@ -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);
--
2.9.3
\
 
 \ /
  Last update: 2017-04-12 14:27    [W:0.113 / U:16.584 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site