bcache: Rewrite patch to delay to invalidate cache data

euleros inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I4LOJ6


CVE: NA

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The recently pushd bugfix patch "Delay to invalidate cache data
in writearound write" has a stupid copy&paste bug, which causes
bypassed write request will never invalidate data in cache device,
causing a data corruption. This patch fixes this corruption.
This patch also ensures that the writeback lock is released after
data insert.

Fixes: 6a1d9c41b367 ("bcache: Delay to invalidate cache data in writearound write")
Signed-off-by: Li Ruilin <liruilin4@huawei.com>
Signed-off-by: Song Chao <chao.song@huawei.com>
Reviewed-by: Peng Junyi <pengjunyi1@huawei.com>
Acked-by: Xie Xiuqi <xiexiuqi@huawei.com>
Signed-off-by: Cheng Jian <cj.chengjian@huawei.com>
Reviewed-by: Guangxing Deng <dengguangxing@huawei.com>
Reviewed-by: chao song <chao.song@huawei.com>
Reviewed-by: chao song <chao.song@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>