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-rw-r--r--mm/hugetlb.c67
1 files changed, 47 insertions, 20 deletions
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 67a71191136e..ce8cbb29860b 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;
@@ -2008,7 +2006,7 @@ int hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma,
entry = huge_ptep_get(ptep);
if (huge_pte_none(entry)) {
ret = hugetlb_no_page(mm, vma, address, ptep, write_access);
- goto out_unlock;
+ goto out_mutex;
}
ret = 0;
@@ -2024,7 +2022,7 @@ int hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma,
if (write_access && !pte_write(entry)) {
if (vma_needs_reservation(h, vma, address) < 0) {
ret = VM_FAULT_OOM;
- goto out_unlock;
+ goto out_mutex;
}
if (!(vma->vm_flags & VM_SHARED))
@@ -2034,10 +2032,23 @@ int hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma,
spin_lock(&mm->page_table_lock);
/* Check for a racing update before calling hugetlb_cow */
- if (likely(pte_same(entry, huge_ptep_get(ptep))))
- if (write_access && !pte_write(entry))
+ if (unlikely(!pte_same(entry, huge_ptep_get(ptep))))
+ goto out_page_table_lock;
+
+
+ if (write_access) {
+ if (!pte_write(entry)) {
ret = hugetlb_cow(mm, vma, address, ptep, entry,
pagecache_page);
+ goto out_page_table_lock;
+ }
+ entry = pte_mkdirty(entry);
+ }
+ entry = pte_mkyoung(entry);
+ if (huge_ptep_set_access_flags(vma, address, ptep, entry, write_access))
+ update_mmu_cache(vma, address, entry);
+
+out_page_table_lock:
spin_unlock(&mm->page_table_lock);
if (pagecache_page) {
@@ -2045,7 +2056,7 @@ int hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma,
put_page(pagecache_page);
}
-out_unlock:
+out_mutex:
mutex_unlock(&hugetlb_instantiation_mutex);
return ret;
@@ -2060,6 +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,
@@ -2069,6 +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) {
@@ -2081,8 +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;
@@ -2102,8 +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)
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