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Subject[PATCH] f2fs: Use memcpy_page() in f2fs_copy_page()
The use of kmap() is being deprecated in favor of kmap_local_page().

Two main problems with kmap(): (1) It comes with an overhead as mapping
space is restricted and protected by a global lock for synchronization and
(2) it also requires global TLB invalidation when the kmap’s pool wraps
and it might block when the mapping space is fully utilized until a slot
becomes available.

Therefore, replace kmap() with kmap_local_page() in f2fs_copy_page() and
use memcpy_page() instead of open coding kmap_local_page() + memcpy().

Suggested-by: Ira Weiny <>
Signed-off-by: Fabio M. De Francesco <>
fs/f2fs/f2fs.h | 6 +-----
1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index d9bbecd008d2..f04e760bb1c1 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -2698,12 +2698,8 @@ static inline struct page *f2fs_pagecache_get_page(

static inline void f2fs_copy_page(struct page *src, struct page *dst)
- char *src_kaddr = kmap(src);
- char *dst_kaddr = kmap(dst);

- memcpy(dst_kaddr, src_kaddr, PAGE_SIZE);
- kunmap(dst);
- kunmap(src);
+ memcpy_page(dst, 0, src, 0, PAGE_SIZE);

static inline void f2fs_put_page(struct page *page, int unlock)
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