From: Eric Biggers <ebiggers@kernel.org>
To: "Darrick J. Wong" <djwong@kernel.org>
Cc: jane.chu@oracle.com, linux-xfs@vger.kernel.org,
hch@infradead.org, dan.j.williams@intel.com,
linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH 3/5] vfs: add a zero-initialization mode to fallocate
Date: Mon, 20 Sep 2021 10:52:09 -0700 [thread overview]
Message-ID: <YUjKSclPPWFmZHwZ@gmail.com> (raw)
In-Reply-To: <163192866125.417973.7293598039998376121.stgit@magnolia>
On Fri, Sep 17, 2021 at 06:31:01PM -0700, Darrick J. Wong wrote:
> From: Darrick J. Wong <djwong@kernel.org>
>
> Add a new mode to fallocate to zero-initialize all the storage backing a
> file.
>
> Signed-off-by: Darrick J. Wong <djwong@kernel.org>
> ---
> fs/open.c | 5 +++++
> include/linux/falloc.h | 1 +
> include/uapi/linux/falloc.h | 9 +++++++++
> 3 files changed, 15 insertions(+)
>
>
> diff --git a/fs/open.c b/fs/open.c
> index daa324606a41..230220b8f67a 100644
> --- a/fs/open.c
> +++ b/fs/open.c
> @@ -256,6 +256,11 @@ int vfs_fallocate(struct file *file, int mode, loff_t offset, loff_t len)
> (mode & ~FALLOC_FL_INSERT_RANGE))
> return -EINVAL;
>
> + /* Zeroinit should only be used by itself and keep size must be set. */
> + if ((mode & FALLOC_FL_ZEROINIT_RANGE) &&
> + (mode != (FALLOC_FL_ZEROINIT_RANGE | FALLOC_FL_KEEP_SIZE)))
> + return -EINVAL;
> +
> /* Unshare range should only be used with allocate mode. */
> if ((mode & FALLOC_FL_UNSHARE_RANGE) &&
> (mode & ~(FALLOC_FL_UNSHARE_RANGE | FALLOC_FL_KEEP_SIZE)))
> diff --git a/include/linux/falloc.h b/include/linux/falloc.h
> index f3f0b97b1675..4597b416667b 100644
> --- a/include/linux/falloc.h
> +++ b/include/linux/falloc.h
> @@ -29,6 +29,7 @@ struct space_resv {
> FALLOC_FL_PUNCH_HOLE | \
> FALLOC_FL_COLLAPSE_RANGE | \
> FALLOC_FL_ZERO_RANGE | \
> + FALLOC_FL_ZEROINIT_RANGE | \
> FALLOC_FL_INSERT_RANGE | \
> FALLOC_FL_UNSHARE_RANGE)
>
> diff --git a/include/uapi/linux/falloc.h b/include/uapi/linux/falloc.h
> index 51398fa57f6c..8144403b6102 100644
> --- a/include/uapi/linux/falloc.h
> +++ b/include/uapi/linux/falloc.h
> @@ -77,4 +77,13 @@
> */
> #define FALLOC_FL_UNSHARE_RANGE 0x40
>
> +/*
> + * FALLOC_FL_ZEROINIT_RANGE is used to reinitialize storage backing a file by
> + * writing zeros to it. Subsequent read and writes should not fail due to any
> + * previous media errors. Blocks must be not be shared or require copy on
> + * write. Holes and unwritten extents are left untouched. This mode must be
> + * used with FALLOC_FL_KEEP_SIZE.
> + */
> +#define FALLOC_FL_ZEROINIT_RANGE 0x80
> +
How does this differ from ZERO_RANGE? Especially when the above says that
ZEROINIT_RANGE leaves unwritten extents untouched. That implies that unwritten
extents are still "allowed". If that's the case, why not just use ZERO_RANGE?
- Eric
next prev parent reply other threads:[~2021-09-20 18:55 UTC|newest]
Thread overview: 49+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-09-18 1:30 [PATCHSET RFC v2 jane 0/5] vfs: enable userspace to reset damaged file storage Darrick J. Wong
2021-09-18 1:30 ` [PATCH 1/5] dax: prepare pmem for use by zero-initializing contents and clearing poisons Darrick J. Wong
2021-09-18 16:54 ` riteshh
2021-09-20 17:22 ` Darrick J. Wong
2021-09-21 4:07 ` riteshh
2021-09-22 18:26 ` Darrick J. Wong
2021-09-22 19:47 ` riteshh
2021-09-22 20:26 ` Dan Williams
2021-09-21 8:34 ` Christoph Hellwig
2021-09-22 18:10 ` Darrick J. Wong
2021-09-18 1:30 ` [PATCH 2/5] iomap: use accelerated zeroing on a block device to zero a file range Darrick J. Wong
2021-09-18 16:55 ` riteshh
2021-09-21 8:29 ` Christoph Hellwig
2021-09-22 18:53 ` Darrick J. Wong
2021-09-21 22:33 ` Dave Chinner
2021-09-22 18:54 ` Darrick J. Wong
2021-09-18 1:31 ` [PATCH 3/5] vfs: add a zero-initialization mode to fallocate Darrick J. Wong
2021-09-18 16:58 ` riteshh
2021-09-20 17:52 ` Eric Biggers [this message]
2021-09-20 18:06 ` Darrick J. Wong
2021-09-21 0:44 ` Dave Chinner
2021-09-21 8:31 ` Christoph Hellwig
2021-09-22 2:16 ` Dan Williams
2021-09-22 2:38 ` Darrick J. Wong
2021-09-22 3:59 ` Dave Chinner
2021-09-22 4:13 ` Darrick J. Wong
2021-09-22 5:49 ` Dave Chinner
2021-09-22 21:27 ` Darrick J. Wong
2021-09-23 0:02 ` Darrick J. Wong
2021-09-23 0:44 ` Darrick J. Wong
2021-09-23 1:42 ` Dave Chinner
2021-09-23 2:43 ` Dan Williams
2021-09-23 5:42 ` Dan Williams
2021-09-23 22:54 ` Dave Chinner
2021-09-24 1:18 ` Dan Williams
2021-09-24 1:21 ` Jane Chu
2021-09-24 1:35 ` Darrick J. Wong
2021-09-27 21:07 ` Dave Chinner
2021-09-27 21:57 ` Jane Chu
2021-09-28 0:08 ` Dan Williams
2021-09-22 5:28 ` riteshh
2021-09-18 1:31 ` [PATCH 4/5] xfs: implement FALLOC_FL_ZEROINIT_RANGE Darrick J. Wong
2021-09-18 1:31 ` [PATCH 5/5] ext4: " Darrick J. Wong
2021-09-18 17:07 ` riteshh
2021-09-20 18:11 ` Darrick J. Wong
2021-09-21 6:10 ` riteshh
2021-09-18 18:05 ` [PATCHSET RFC v2 jane 0/5] vfs: enable userspace to reset damaged file storage Dan Williams
2021-09-23 0:51 ` Darrick J. Wong
2021-09-23 1:17 ` Dan Williams
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=YUjKSclPPWFmZHwZ@gmail.com \
--to=ebiggers@kernel.org \
--cc=dan.j.williams@intel.com \
--cc=djwong@kernel.org \
--cc=hch@infradead.org \
--cc=jane.chu@oracle.com \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-xfs@vger.kernel.org \
/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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.