From: Christoph Hellwig <hch@infradead.org>
To: Zhang Yi <yi.zhang@huaweicloud.com>
Cc: "Darrick J. Wong" <djwong@kernel.org>,
Christoph Hellwig <hch@infradead.org>,
Theodore Ts'o <tytso@mit.edu>,
linux-fsdevel@vger.kernel.org, linux-ext4@vger.kernel.org,
linux-kernel@vger.kernel.org, viro@zeniv.linux.org.uk,
brauner@kernel.org, jack@suse.cz, adilger.kernel@dilger.ca,
yi.zhang@huawei.com, chengzhihao1@huawei.com, yukuai3@huawei.com,
yangerkun@huawei.com, Sai Chaitanya Mitta <mittachaitu@gmail.com>,
linux-xfs@vger.kernel.org
Subject: Re: [RFC PATCH 1/2] fs: introduce FALLOC_FL_FORCE_ZERO to fallocate
Date: Tue, 7 Jan 2025 08:42:19 -0800 [thread overview]
Message-ID: <Z31Za6Ma97QPHp1W@infradead.org> (raw)
In-Reply-To: <b964a57a-0237-4cbd-9aae-457527a44440@huaweicloud.com>
On Tue, Jan 07, 2025 at 10:05:47PM +0800, Zhang Yi wrote:
> Sorry. the "pure overwrites" and "always-cow files" makes me confused,
> this is mainly used to create a new written file range, but also could
> be used to zero out an existing range, why you mentioned it exists to
> facilitate pure overwrites?
If you're fine with writes to your file causing block allocations you
can already use the hole punch or preallocate fallocate modes. No
need to actually send a command to the device.
>
> For the "always-cow files", do you mean reflinked files? Could you
> please give more details?
reflinked files will require out of place writes for shared blocks.
As will anything on device mapper snapshots. Or any file on
file systems that write out of place (btrfs, f2fs, nilfs2, the
upcoming zoned xfs mode).
next prev parent reply other threads:[~2025-01-07 16:42 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-12-28 1:45 [RFC PATCH 0/2] fallocate: introduce FALLOC_FL_FORCE_ZERO flag Zhang Yi
2024-12-28 1:45 ` [RFC PATCH 1/2] fs: introduce FALLOC_FL_FORCE_ZERO to fallocate Zhang Yi
2025-01-06 11:27 ` Christoph Hellwig
2025-01-06 16:17 ` Theodore Ts'o
2025-01-06 16:27 ` Christoph Hellwig
2025-01-06 17:31 ` Darrick J. Wong
2025-01-06 18:06 ` Christoph Hellwig
2025-01-07 14:05 ` Zhang Yi
2025-01-07 16:42 ` Christoph Hellwig [this message]
2025-01-08 1:20 ` Zhang Yi
2025-01-07 11:22 ` Zhang Yi
2025-01-07 12:38 ` Zhang Yi
2024-12-28 1:45 ` [RFC PATCH 2/2] ext4: add FALLOC_FL_FORCE_ZERO support Zhang Yi
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=Z31Za6Ma97QPHp1W@infradead.org \
--to=hch@infradead.org \
--cc=adilger.kernel@dilger.ca \
--cc=brauner@kernel.org \
--cc=chengzhihao1@huawei.com \
--cc=djwong@kernel.org \
--cc=jack@suse.cz \
--cc=linux-ext4@vger.kernel.org \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-xfs@vger.kernel.org \
--cc=mittachaitu@gmail.com \
--cc=tytso@mit.edu \
--cc=viro@zeniv.linux.org.uk \
--cc=yangerkun@huawei.com \
--cc=yi.zhang@huawei.com \
--cc=yi.zhang@huaweicloud.com \
--cc=yukuai3@huawei.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox