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Diffstat (limited to 'mm/swapfile.c')
-rw-r--r--mm/swapfile.c15
1 files changed, 14 insertions, 1 deletions
diff --git a/mm/swapfile.c b/mm/swapfile.c
index 9b51266413cd..c72c648f750c 100644
--- a/mm/swapfile.c
+++ b/mm/swapfile.c
@@ -874,11 +874,17 @@ unsigned int count_swap_pages(int type, int free)
static int unuse_pte(struct vm_area_struct *vma, pmd_t *pmd,
unsigned long addr, swp_entry_t entry, struct page *page)
{
+ struct page *swapcache;
struct mem_cgroup *memcg;
spinlock_t *ptl;
pte_t *pte;
int ret = 1;
+ swapcache = page;
+ page = ksm_might_need_to_copy(page, vma, addr);
+ if (unlikely(!page))
+ return -ENOMEM;
+
if (mem_cgroup_try_charge_swapin(vma->vm_mm, page,
GFP_KERNEL, &memcg)) {
ret = -ENOMEM;
@@ -897,7 +903,10 @@ static int unuse_pte(struct vm_area_struct *vma, pmd_t *pmd,
get_page(page);
set_pte_at(vma->vm_mm, addr, pte,
pte_mkold(mk_pte(page, vma->vm_page_prot)));
- page_add_anon_rmap(page, vma, addr);
+ if (page == swapcache)
+ page_add_anon_rmap(page, vma, addr);
+ else /* ksm created a completely new copy */
+ page_add_new_anon_rmap(page, vma, addr);
mem_cgroup_commit_charge_swapin(page, memcg);
swap_free(entry);
/*
@@ -908,6 +917,10 @@ static int unuse_pte(struct vm_area_struct *vma, pmd_t *pmd,
out:
pte_unmap_unlock(pte, ptl);
out_nolock:
+ if (page != swapcache) {
+ unlock_page(page);
+ put_page(page);
+ }
return ret;
}