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Diffstat (limited to 'mm/hugetlb.c')
-rw-r--r--mm/hugetlb.c44
1 files changed, 42 insertions, 2 deletions
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 54d42b009dbe..aa3c51739378 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -18,6 +18,7 @@
#include <linux/bootmem.h>
#include <linux/sysfs.h>
#include <linux/slab.h>
+#include <linux/rmap.h>
#include <asm/page.h>
#include <asm/pgtable.h>
@@ -220,6 +221,12 @@ static pgoff_t vma_hugecache_offset(struct hstate *h,
(vma->vm_pgoff >> huge_page_order(h));
}
+pgoff_t linear_hugepage_index(struct vm_area_struct *vma,
+ unsigned long address)
+{
+ return vma_hugecache_offset(hstate_vma(vma), vma, address);
+}
+
/*
* Return the size of the pages allocated when backing a VMA. In the majority
* cases this will be same size as used by the page table entries.
@@ -552,6 +559,7 @@ static void free_huge_page(struct page *page)
set_page_private(page, 0);
page->mapping = NULL;
BUG_ON(page_count(page));
+ BUG_ON(page_mapcount(page));
INIT_LIST_HEAD(&page->lru);
spin_lock(&hugetlb_lock);
@@ -2129,6 +2137,7 @@ int copy_hugetlb_page_range(struct mm_struct *dst, struct mm_struct *src,
entry = huge_ptep_get(src_pte);
ptepage = pte_page(entry);
get_page(ptepage);
+ page_dup_rmap(ptepage);
set_huge_pte_at(dst, addr, dst_pte, entry);
}
spin_unlock(&src->page_table_lock);
@@ -2207,6 +2216,7 @@ void __unmap_hugepage_range(struct vm_area_struct *vma, unsigned long start,
flush_tlb_range(vma, start, end);
mmu_notifier_invalidate_range_end(mm, start, end);
list_for_each_entry_safe(page, tmp, &page_list, lru) {
+ page_remove_rmap(page);
list_del(&page->lru);
put_page(page);
}
@@ -2272,6 +2282,9 @@ static int unmap_ref_private(struct mm_struct *mm, struct vm_area_struct *vma,
return 1;
}
+/*
+ * Hugetlb_cow() should be called with page lock of the original hugepage held.
+ */
static int hugetlb_cow(struct mm_struct *mm, struct vm_area_struct *vma,
unsigned long address, pte_t *ptep, pte_t pte,
struct page *pagecache_page)
@@ -2286,8 +2299,11 @@ static int hugetlb_cow(struct mm_struct *mm, struct vm_area_struct *vma,
retry_avoidcopy:
/* If no-one else is actually using this page, avoid the copy
* and just make the page writable */
- avoidcopy = (page_count(old_page) == 1);
+ avoidcopy = (page_mapcount(old_page) == 1);
if (avoidcopy) {
+ if (!trylock_page(old_page))
+ if (PageAnon(old_page))
+ page_move_anon_rmap(old_page, vma, address);
set_huge_ptep_writable(vma, address, ptep);
return 0;
}
@@ -2338,6 +2354,13 @@ retry_avoidcopy:
return -PTR_ERR(new_page);
}
+ /*
+ * When the original hugepage is shared one, it does not have
+ * anon_vma prepared.
+ */
+ if (unlikely(anon_vma_prepare(vma)))
+ return VM_FAULT_OOM;
+
copy_huge_page(new_page, old_page, address, vma);
__SetPageUptodate(new_page);
@@ -2352,6 +2375,8 @@ retry_avoidcopy:
huge_ptep_clear_flush(vma, address, ptep);
set_huge_pte_at(mm, address, ptep,
make_huge_pte(vma, new_page, 1));
+ page_remove_rmap(old_page);
+ hugepage_add_anon_rmap(new_page, vma, address);
/* Make the old page be freed below */
new_page = old_page;
}
@@ -2452,10 +2477,17 @@ retry:
spin_lock(&inode->i_lock);
inode->i_blocks += blocks_per_huge_page(h);
spin_unlock(&inode->i_lock);
+ page_dup_rmap(page);
} else {
lock_page(page);
- page->mapping = HUGETLB_POISON;
+ if (unlikely(anon_vma_prepare(vma))) {
+ ret = VM_FAULT_OOM;
+ goto backout_unlocked;
+ }
+ hugepage_add_new_anon_rmap(page, vma, address);
}
+ } else {
+ page_dup_rmap(page);
}
/*
@@ -2507,6 +2539,7 @@ int hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma,
pte_t *ptep;
pte_t entry;
int ret;
+ struct page *page = NULL;
struct page *pagecache_page = NULL;
static DEFINE_MUTEX(hugetlb_instantiation_mutex);
struct hstate *h = hstate_vma(vma);
@@ -2548,6 +2581,11 @@ int hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma,
vma, address);
}
+ if (!pagecache_page) {
+ page = pte_page(entry);
+ lock_page(page);
+ }
+
spin_lock(&mm->page_table_lock);
/* Check for a racing update before calling hugetlb_cow */
if (unlikely(!pte_same(entry, huge_ptep_get(ptep))))
@@ -2573,6 +2611,8 @@ out_page_table_lock:
if (pagecache_page) {
unlock_page(pagecache_page);
put_page(pagecache_page);
+ } else {
+ unlock_page(page);
}
out_mutex: