x86: PAT use reserve free memtype in mmap of /dev/mem
Use reserve_memtype and free_memtype wrappers for /dev/mem mmaps. The memtype
is slightly complicated here, given that we have to support existing X mappings.
We fallback on UC_MINUS for that.
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/drivers/char/mem.c b/drivers/char/mem.c
index 56b2fb4..e83623e 100644
--- a/drivers/char/mem.c
+++ b/drivers/char/mem.c
@@ -300,6 +300,35 @@
}
#endif
+void __attribute__((weak))
+map_devmem(unsigned long pfn, unsigned long len, pgprot_t prot)
+{
+ /* nothing. architectures can override. */
+}
+
+void __attribute__((weak))
+unmap_devmem(unsigned long pfn, unsigned long len, pgprot_t prot)
+{
+ /* nothing. architectures can override. */
+}
+
+static void mmap_mem_open(struct vm_area_struct *vma)
+{
+ map_devmem(vma->vm_pgoff, vma->vm_end - vma->vm_start,
+ vma->vm_page_prot);
+}
+
+static void mmap_mem_close(struct vm_area_struct *vma)
+{
+ unmap_devmem(vma->vm_pgoff, vma->vm_end - vma->vm_start,
+ vma->vm_page_prot);
+}
+
+static struct vm_operations_struct mmap_mem_ops = {
+ .open = mmap_mem_open,
+ .close = mmap_mem_close
+};
+
static int mmap_mem(struct file * file, struct vm_area_struct * vma)
{
size_t size = vma->vm_end - vma->vm_start;
@@ -321,13 +350,17 @@
size,
vma->vm_page_prot);
+ vma->vm_ops = &mmap_mem_ops;
+
/* Remap-pfn-range will mark the range VM_IO and VM_RESERVED */
if (remap_pfn_range(vma,
vma->vm_start,
vma->vm_pgoff,
size,
- vma->vm_page_prot))
+ vma->vm_page_prot)) {
+ unmap_devmem(vma->vm_pgoff, size, vma->vm_page_prot);
return -EAGAIN;
+ }
return 0;
}