mm/rmap: make rmap_walk to get the rmap_walk_control argument

In each rmap traverse case, there is some difference so that we need
function pointers and arguments to them in order to handle these

For this purpose, struct rmap_walk_control is introduced in this patch,
and will be extended in following patch.  Introducing and extending are
separate, because it clarify changes.

Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Hugh Dickins <hughd@google.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Hillf Danton <dhillf@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 3 insertions, 3 deletions

diff --git a/mm/ksm.c b/mm/ksm.c
index 175fff79dc95..c3035fee8080 100644
--- a/mm/ksm.c
+++ b/mm/ksm.c
@@ -1997,8 +1997,7 @@ out:
 }
 
 #ifdef CONFIG_MIGRATION
-int rmap_walk_ksm(struct page *page, int (*rmap_one)(struct page *,
-                  struct vm_area_struct *, unsigned long, void *), void *arg)
+int rmap_walk_ksm(struct page *page, struct rmap_walk_control *rwc)
 {
         struct stable_node *stable_node;
         struct rmap_item *rmap_item;
@@ -2033,7 +2032,8 @@ again:
                         if ((rmap_item->mm == vma->vm_mm) == search_new_forks)
                                 continue;
 
-                        ret = rmap_one(page, vma, rmap_item->address, arg);
+                        ret = rwc->rmap_one(page, vma,
+                                        rmap_item->address, rwc->arg);
                         if (ret != SWAP_AGAIN) {
                                 anon_vma_unlock_read(anon_vma);
                                 goto out;