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Subject: Re: [PATCH] f2fs: introduce nosmall_discard mount option
To:     Jaegeuk Kim <jaegeuk@kernel.org>
Cc:     linux-f2fs-devel@lists.sourceforge.net,
        linux-kernel@vger.kernel.org, Chao Yu <chao.yu@linux.dev>
References: <20210730100530.4401-1-chao@kernel.org>
 <YQREtmDLBNKSQViC@google.com>
From:   Chao Yu <chao@kernel.org>
Message-ID: <c0af2126-7383-a579-e020-6480216c46fe@kernel.org>
Date:   Sat, 31 Jul 2021 07:41:17 +0800
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On 2021/7/31 2:28, Jaegeuk Kim wrote:
> how about adding "discard_gran=[small|segment|section]", and keeping discard_map
> in the small case only? And, I think we should set the section mode for zoned
> device automatically.

Yup, better,

About the naming, it look discard_gran is not clear here, since there is another
sysfs entry /sys/fs/f2fs/<devname>/discard_granularity has the same name, and
also semantics of newly added mount option is not only control the smallest discard
size, but also indicate discard start offset should be aligned to segment or section.
So how about using: "aligned_discard=[none|segment|section]" instead?

Thanks,