euleros inclusion
category: feature
bugzilla: https://bugzilla.openeuler.org/show_bug.cgi?id=26
CVE: NA

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provide a switch named read_bypass. If enbale, all IO requests will
bypass the cache. This option could be useful when we enable userspace
prefetch and the cache device is low capacity.
Signed-off-by: NLi Ruilin <liruilin4@huawei.com>
Reviewed-by: NLuan Jianhai <luanjianhai@huawei.com>
Reviewed-by: NPeng Junyi <pengjunyi1@huawei.com>
Acked-by: NXie Xiuqi <xiexiuqi@huawei.com>
Signed-off-by: NCheng Jian <cj.chengjian@huawei.com>