X-Git-Url: http://pilppa.org/gitweb/gitweb.cgi?a=blobdiff_plain;f=mm%2Fhugetlb.c;h=ce8cbb29860bd1b867454014195fe497332e2f61;hb=296e1ce0dc36bb106c139e25482d02da43c70e71;hp=38633864a93e874009d9e6aa00619cf7471b0d9e;hpb=52f4f324c727e77507ae0490b08fc92e140ba57d;p=linux-2.6-omap-h63xx.git

diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 38633864a93..ce8cbb29860 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -262,7 +262,7 @@ struct resv_map {
 	struct list_head regions;
 };
 
-struct resv_map *resv_map_alloc(void)
+static struct resv_map *resv_map_alloc(void)
 {
 	struct resv_map *resv_map = kmalloc(sizeof(*resv_map), GFP_KERNEL);
 	if (!resv_map)
@@ -274,7 +274,7 @@ struct resv_map *resv_map_alloc(void)
 	return resv_map;
 }
 
-void resv_map_release(struct kref *ref)
+static void resv_map_release(struct kref *ref)
 {
 	struct resv_map *resv_map = container_of(ref, struct resv_map, refs);
 
@@ -289,7 +289,7 @@ static struct resv_map *vma_resv_map(struct vm_area_struct *vma)
 	if (!(vma->vm_flags & VM_SHARED))
 		return (struct resv_map *)(get_vma_private_data(vma) &
 							~HPAGE_RESV_MASK);
-	return 0;
+	return NULL;
 }
 
 static void set_vma_resv_map(struct vm_area_struct *vma, struct resv_map *map)
@@ -1459,11 +1459,11 @@ int hugetlb_report_meminfo(char *buf)
 {
 	struct hstate *h = &default_hstate;
 	return sprintf(buf,
-			"HugePages_Total: %5lu\n"
-			"HugePages_Free:  %5lu\n"
-			"HugePages_Rsvd:  %5lu\n"
-			"HugePages_Surp:  %5lu\n"
-			"Hugepagesize:    %5lu kB\n",
+			"HugePages_Total:   %5lu\n"
+			"HugePages_Free:    %5lu\n"
+			"HugePages_Rsvd:    %5lu\n"
+			"HugePages_Surp:    %5lu\n"
+			"Hugepagesize:   %8lu kB\n",
 			h->nr_huge_pages,
 			h->free_huge_pages,
 			h->resv_huge_pages,
@@ -1747,10 +1747,8 @@ void unmap_hugepage_range(struct vm_area_struct *vma, unsigned long start,
  * from other VMAs and let the children be SIGKILLed if they are faulting the
  * same region.
  */
-int unmap_ref_private(struct mm_struct *mm,
-					struct vm_area_struct *vma,
-					struct page *page,
-					unsigned long address)
+static int unmap_ref_private(struct mm_struct *mm, struct vm_area_struct *vma,
+				struct page *page, unsigned long address)
 {
 	struct vm_area_struct *iter_vma;
 	struct address_space *mapping;
@@ -2073,6 +2071,14 @@ follow_huge_pud(struct mm_struct *mm, unsigned long address,
 	return NULL;
 }
 
+static int huge_zeropage_ok(pte_t *ptep, int write, int shared)
+{
+	if (!ptep || write || shared)
+		return 0;
+	else
+		return huge_pte_none(huge_ptep_get(ptep));
+}
+
 int follow_hugetlb_page(struct mm_struct *mm, struct vm_area_struct *vma,
 			struct page **pages, struct vm_area_struct **vmas,
 			unsigned long *position, int *length, int i,
@@ -2082,6 +2088,8 @@ int follow_hugetlb_page(struct mm_struct *mm, struct vm_area_struct *vma,
 	unsigned long vaddr = *position;
 	int remainder = *length;
 	struct hstate *h = hstate_vma(vma);
+	int zeropage_ok = 0;
+	int shared = vma->vm_flags & VM_SHARED;
 
 	spin_lock(&mm->page_table_lock);
 	while (vaddr < vma->vm_end && remainder) {
@@ -2094,8 +2102,11 @@ int follow_hugetlb_page(struct mm_struct *mm, struct vm_area_struct *vma,
 		 * first, for the page indexing below to work.
 		 */
 		pte = huge_pte_offset(mm, vaddr & huge_page_mask(h));
+		if (huge_zeropage_ok(pte, write, shared))
+			zeropage_ok = 1;
 
-		if (!pte || huge_pte_none(huge_ptep_get(pte)) ||
+		if (!pte ||
+		    (huge_pte_none(huge_ptep_get(pte)) && !zeropage_ok) ||
 		    (write && !pte_write(huge_ptep_get(pte)))) {
 			int ret;
 
@@ -2115,8 +2126,11 @@ int follow_hugetlb_page(struct mm_struct *mm, struct vm_area_struct *vma,
 		page = pte_page(huge_ptep_get(pte));
 same_page:
 		if (pages) {
-			get_page(page);
-			pages[i] = page + pfn_offset;
+			if (zeropage_ok)
+				pages[i] = ZERO_PAGE(0);
+			else
+				pages[i] = page + pfn_offset;
+			get_page(pages[i]);
 		}
 
 		if (vmas)