use clear_page()/copy_page() in favor of memset()/memcpy() on whole pages

After all that's what they are intended for.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

5 files changed, 13 insertions, 13 deletions

diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c
index cde755cca564..69037118b2c9 100644
--- a/fs/fuse/dev.c
+++ b/fs/fuse/dev.c
@@ -811,7 +811,7 @@ static int fuse_copy_page(struct fuse_copy_state *cs, struct page **pagep,
 
         if (page && zeroing && count < PAGE_SIZE) {
                 void *mapaddr = kmap_atomic(page, KM_USER1);
-                memset(mapaddr, 0, PAGE_SIZE);
+                clear_page(mapaddr);
                 kunmap_atomic(mapaddr, KM_USER1);
         }
         while (count) {
diff --git a/kernel/kexec.c b/kernel/kexec.c
index c0613f7d6730..b55045bc7563 100644
--- a/kernel/kexec.c
+++ b/kernel/kexec.c
@@ -816,7 +816,7 @@ static int kimage_load_normal_segment(struct kimage *image,
 
                 ptr = kmap(page);
                 /* Start with a clear page */
-                memset(ptr, 0, PAGE_SIZE);
+                clear_page(ptr);
                 ptr += maddr & ~PAGE_MASK;
                 mchunk = PAGE_SIZE - (maddr & ~PAGE_MASK);
                 if (mchunk > mbytes)
diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c
index 9e3581f4619a..0dac75ea4456 100644
--- a/kernel/power/snapshot.c
+++ b/kernel/power/snapshot.c
@@ -993,7 +993,7 @@ static void copy_data_page(unsigned long dst_pfn, unsigned long src_pfn)
                          */
                         safe_copy_page(buffer, s_page);
                         dst = kmap_atomic(d_page, KM_USER0);
-                        memcpy(dst, buffer, PAGE_SIZE);
+                        copy_page(dst, buffer);
                         kunmap_atomic(dst, KM_USER0);
                 } else {
                         safe_copy_page(page_address(d_page), s_page);
@@ -1687,7 +1687,7 @@ int snapshot_read_next(struct snapshot_handle *handle)
                 memory_bm_position_reset(&orig_bm);
                 memory_bm_position_reset(&copy_bm);
         } else if (handle->cur <= nr_meta_pages) {
-                memset(buffer, 0, PAGE_SIZE);
+                clear_page(buffer);
                 pack_pfns(buffer, &orig_bm);
         } else {
                 struct page *page;
@@ -1701,7 +1701,7 @@ int snapshot_read_next(struct snapshot_handle *handle)
                         void *kaddr;
 
                         kaddr = kmap_atomic(page, KM_USER0);
-                        memcpy(buffer, kaddr, PAGE_SIZE);
+                        copy_page(buffer, kaddr);
                         kunmap_atomic(kaddr, KM_USER0);
                         handle->buffer = buffer;
                 } else {
@@ -1984,7 +1984,7 @@ static void copy_last_highmem_page(void)
                 void *dst;
 
                 dst = kmap_atomic(last_highmem_page, KM_USER0);
-                memcpy(dst, buffer, PAGE_SIZE);
+                copy_page(dst, buffer);
                 kunmap_atomic(dst, KM_USER0);
                 last_highmem_page = NULL;
         }
@@ -2270,9 +2270,9 @@ swap_two_pages_data(struct page *p1, struct page *p2, void *buf)
 
         kaddr1 = kmap_atomic(p1, KM_USER0);
         kaddr2 = kmap_atomic(p2, KM_USER1);
-        memcpy(buf, kaddr1, PAGE_SIZE);
-        memcpy(kaddr1, kaddr2, PAGE_SIZE);
-        memcpy(kaddr2, buf, PAGE_SIZE);
+        copy_page(buf, kaddr1);
+        copy_page(kaddr1, kaddr2);
+        copy_page(kaddr2, buf);
         kunmap_atomic(kaddr2, KM_USER1);
         kunmap_atomic(kaddr1, KM_USER0);
 }
diff --git a/kernel/power/swap.c b/kernel/power/swap.c
index 916eaa790399..a0e4a86ccf94 100644
--- a/kernel/power/swap.c
+++ b/kernel/power/swap.c
@@ -251,7 +251,7 @@ static int write_page(void *buf, sector_t offset, struct bio **bio_chain)
         if (bio_chain) {
                 src = (void *)__get_free_page(__GFP_WAIT | __GFP_HIGH);
                 if (src) {
-                        memcpy(src, buf, PAGE_SIZE);
+                        copy_page(src, buf);
                 } else {
                         WARN_ON_ONCE(1);
                         bio_chain = NULL;       /* Go synchronous */
@@ -325,7 +325,7 @@ static int swap_write_page(struct swap_map_handle *handle, void *buf,
                 error = write_page(handle->cur, handle->cur_swap, NULL);
                 if (error)
                         goto out;
-                memset(handle->cur, 0, PAGE_SIZE);
+                clear_page(handle->cur);
                 handle->cur_swap = offset;
                 handle->k = 0;
         }
@@ -910,7 +910,7 @@ int swsusp_check(void)
         hib_resume_bdev = open_by_devnum(swsusp_resume_device, FMODE_READ);
         if (!IS_ERR(hib_resume_bdev)) {
                 set_blocksize(hib_resume_bdev, PAGE_SIZE);
-                memset(swsusp_header, 0, PAGE_SIZE);
+                clear_page(swsusp_header);
                 error = hib_bio_read_page(swsusp_resume_block,
                                         swsusp_header, NULL);
                 if (error)
diff --git a/mm/memory.c b/mm/memory.c
index 861f7982dd54..02e48aa0ed13 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -2080,7 +2080,7 @@ static inline void cow_user_page(struct page *dst, struct page *src, unsigned lo
                  * zeroes.
                  */
                 if (__copy_from_user_inatomic(kaddr, uaddr, PAGE_SIZE))
-                        memset(kaddr, 0, PAGE_SIZE);
+                        clear_page(kaddr);
                 kunmap_atomic(kaddr, KM_USER0);
                 flush_dcache_page(dst);
         } else