ext4: use memcpy_to_page() in pagecache_write()

stable inclusion
from stable-v5.10.163
commit b33e42d65efe06bb6d6281238d66f4c9573910f2
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I7PJ9N

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=b33e42d65efe06bb6d6281238d66f4c9573910f2



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[ Upstream commit bd256fda ]

Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Link: https://lore.kernel.org/r/20210207190425.38107-7-chaitanya.kulkarni@wdc.com


Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Stable-dep-of: 956510c0 ("fs: ext4: initialize fsdata in pagecache_write()")
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: zhaoxiaoqiang11 <zhaoxiaoqiang11@jd.com>