Create some new accessors for vma private data to cut down on and contain
the casts. Encapsulates the huge and small page offset calculations. Also
adds a couple of VM_BUG_ONs for consistency.
Signed-off-by: Andy Whitcroft <apw@shadowen.org>
---
mm/hugetlb.c | 56 +++++++++++++++++++++++++++++++++++++++++++-------------
1 files changed, 43 insertions(+), 13 deletions(-)
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 729a830..7a5ac81 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -40,6 +40,26 @@ static int hugetlb_next_nid;
*/
static DEFINE_SPINLOCK(hugetlb_lock);
+/*
+ * Convert the address within this vma to the page offset within
+ * the mapping, in base page units.
+ */
+pgoff_t vma_page_offset(struct vm_area_struct *vma, unsigned long address)
+{
+ return ((address - vma->vm_start) >> PAGE_SHIFT) +
+ (vma->vm_pgoff >> PAGE_SHIFT);
+}
+
+/*
+ * Convert the address within this vma to the page offset within
+ * the mapping, in pagecache page units; huge pages here.
+ */
+pgoff_t vma_pagecache_offset(struct vm_area_struct *vma, unsigned long address)
+{
+ return ((address - vma->vm_start) >> HPAGE_SHIFT) +
+ (vma->vm_pgoff >> (HPAGE_SHIFT - PAGE_SHIFT));
+}
+
#define HPAGE_RESV_OWNER (1UL << (BITS_PER_LONG - 1))
#define HPAGE_RESV_UNMAPPED (1UL << (BITS_PER_LONG - 2))
#define HPAGE_RESV_MASK (HPAGE_RESV_OWNER | HPAGE_RESV_UNMAPPED)
@@ -53,36 +73,48 @@ static DEFINE_SPINLOCK(hugetlb_lock);
* to reset the VMA at fork() time as it is not in use yet and there is no
* chance of the global counters getting corrupted as a result of the values.
*/
+static unsigned long get_vma_private_data(struct vm_area_struct *vma)
+{
+ return (unsigned long)vma->vm_private_data;
+}
+
+static void set_vma_private_data(struct vm_area_struct *vma,
+ unsigned long value)
+{
+ vma->vm_private_data = (void *)value;
+}
+
static unsigned long vma_resv_huge_pages(struct vm_area_struct *vma)
...
