X-Git-Url: http://www.pilppa.org/gitweb/gitweb.cgi?a=blobdiff_plain;f=mm%2Fhugetlb.c;h=e6afe527bd09388872a2e07590b32105f050a579;hb=69d177c2fc702d402b17fdca2190d5a7e3ca55c5;hp=38633864a93e874009d9e6aa00619cf7471b0d9e;hpb=b73b636e8987f8728c6c700377615757691b9a55;p=linux-2.6-omap-h63xx.git

diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 38633864a93..e6afe527bd0 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -7,6 +7,7 @@
 #include <linux/init.h>
 #include <linux/module.h>
 #include <linux/mm.h>
+#include <linux/seq_file.h>
 #include <linux/sysctl.h>
 #include <linux/highmem.h>
 #include <linux/mmu_notifier.h>
@@ -262,7 +263,7 @@ 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 +275,7 @@ 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 +290,7 @@ 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)
@@ -353,11 +354,26 @@ static int vma_has_reserves(struct vm_area_struct *vma)
 	return 0;
 }
 
+static void clear_gigantic_page(struct page *page,
+			unsigned long addr, unsigned long sz)
+{
+	int i;
+	struct page *p = page;
+
+	might_sleep();
+	for (i = 0; i < sz/PAGE_SIZE; i++, p = mem_map_next(p, page, i)) {
+		cond_resched();
+		clear_user_highpage(p, addr + i * PAGE_SIZE);
+	}
+}
 static void clear_huge_page(struct page *page,
 			unsigned long addr, unsigned long sz)
 {
 	int i;
 
+	if (unlikely(sz > MAX_ORDER_NR_PAGES))
+		return clear_gigantic_page(page, addr, sz);
+
 	might_sleep();
 	for (i = 0; i < sz/PAGE_SIZE; i++) {
 		cond_resched();
@@ -365,12 +381,32 @@ static void clear_huge_page(struct page *page,
 	}
 }
 
+static void copy_gigantic_page(struct page *dst, struct page *src,
+			   unsigned long addr, struct vm_area_struct *vma)
+{
+	int i;
+	struct hstate *h = hstate_vma(vma);
+	struct page *dst_base = dst;
+	struct page *src_base = src;
+	might_sleep();
+	for (i = 0; i < pages_per_huge_page(h); ) {
+		cond_resched();
+		copy_user_highpage(dst, src, addr + i*PAGE_SIZE, vma);
+
+		i++;
+		dst = mem_map_next(dst, dst_base, i);
+		src = mem_map_next(src, src_base, i);
+	}
+}
 static void copy_huge_page(struct page *dst, struct page *src,
 			   unsigned long addr, struct vm_area_struct *vma)
 {
 	int i;
 	struct hstate *h = hstate_vma(vma);
 
+	if (unlikely(pages_per_huge_page(h) > MAX_ORDER_NR_PAGES))
+		return copy_gigantic_page(dst, src, addr, vma);
+
 	might_sleep();
 	for (i = 0; i < pages_per_huge_page(h); i++) {
 		cond_resched();
@@ -1455,15 +1491,15 @@ int hugetlb_overcommit_handler(struct ctl_table *table, int write,
 
 #endif /* CONFIG_SYSCTL */
 
-int hugetlb_report_meminfo(char *buf)
+void hugetlb_report_meminfo(struct seq_file *m)
 {
 	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",
+	seq_printf(m,
+			"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 +1783,8 @@ 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 +2107,14 @@ 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 +2124,8 @@ 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 +2138,11 @@ 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 +2162,11 @@ 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] = mem_map_offset(page, pfn_offset);
+			get_page(pages[i]);
 		}
 
 		if (vmas)