mspec: convert nopfn to fault
Nick Piggin [Thu, 24 Jul 2008 04:27:00 +0000 (21:27 -0700)]
[akpm@linux-foundation.org: remove unused variable]
Signed-off-by: Nick Piggin <npiggin@suse.de>
Acked-by: Jes Sorensen <jes@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/char/mspec.c

index fe2a95b..30f095a 100644 (file)
@@ -193,25 +193,23 @@ mspec_close(struct vm_area_struct *vma)
 }
 
 /*
- * mspec_nopfn
+ * mspec_fault
  *
  * Creates a mspec page and maps it to user space.
  */
-static unsigned long
-mspec_nopfn(struct vm_area_struct *vma, unsigned long address)
+static int
+mspec_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
 {
        unsigned long paddr, maddr;
        unsigned long pfn;
-       int index;
+       pgoff_t index = vmf->pgoff;
        struct vma_data *vdata = vma->vm_private_data;
 
-       BUG_ON(address < vdata->vm_start || address >= vdata->vm_end);
-       index = (address - vdata->vm_start) >> PAGE_SHIFT;
        maddr = (volatile unsigned long) vdata->maddr[index];
        if (maddr == 0) {
                maddr = uncached_alloc_page(numa_node_id(), 1);
                if (maddr == 0)
-                       return NOPFN_OOM;
+                       return VM_FAULT_OOM;
 
                spin_lock(&vdata->lock);
                if (vdata->maddr[index] == 0) {
@@ -231,13 +229,20 @@ mspec_nopfn(struct vm_area_struct *vma, unsigned long address)
 
        pfn = paddr >> PAGE_SHIFT;
 
-       return pfn;
+       /*
+        * vm_insert_pfn can fail with -EBUSY, but in that case it will
+        * be because another thread has installed the pte first, so it
+        * is no problem.
+        */
+       vm_insert_pfn(vma, (unsigned long)vmf->virtual_address, pfn);
+
+       return VM_FAULT_NOPAGE;
 }
 
 static struct vm_operations_struct mspec_vm_ops = {
        .open = mspec_open,
        .close = mspec_close,
-       .nopfn = mspec_nopfn
+       .fault = mspec_fault,
 };
 
 /*