From: Chandan Rajendra <chandan@linux.ibm.com>
To: Chao Yu <chao@kernel.org>
Cc: linux-fsdevel@vger.kernel.org, linux-ext4@vger.kernel.org,
linux-f2fs-devel@lists.sourceforge.net,
linux-fscrypt@vger.kernel.org, hch@infradead.org, tytso@mit.edu,
ebiggers@kernel.org, adilger.kernel@dilger.ca,
chandanrmail@gmail.com, jaegeuk@kernel.org
Subject: Re: [f2fs-dev] [PATCH V4 5/8] f2fs: Use read_callbacks for decrypting file data
Date: Mon, 19 Aug 2019 19:03:23 +0530 [thread overview]
Message-ID: <20104514.oSSJcvNEEM@localhost.localdomain> (raw)
In-Reply-To: <bb3dc624-1249-2418-f9da-93da8c11e7f5@kernel.org>
On Sunday, August 18, 2019 7:15:42 PM IST Chao Yu wrote:
> Hi Chandan,
>
> On 2019-8-16 14:18, Chandan Rajendra wrote:
> > F2FS has a copy of "post read processing" code using which encrypted
> > file data is decrypted. This commit replaces it to make use of the
> > generic read_callbacks facility.
>
> I remember that previously Jaegeuk had mentioned f2fs will support compression
> later, and it needs to reuse 'post read processing' fwk.
>
> There is very initial version of compression feature in below link:
>
> https://git.kernel.org/pub/scm/linux/kernel/git/chao/linux.git/log/?h=compression
>
> So my concern is how can we uplift the most common parts of this fwk into vfs,
> and meanwhile keeping the ability and flexibility when introducing private
> feature/step in specified filesytem(now f2fs)?
>
> According to current f2fs compression's requirement, maybe we can expand to
>
> - support callback to let filesystem set the function for the flow in
> decompression/verity/decryption step.
> - support to use individual/common workqueue according the parameter.
>
> Any thoughts?
>
Hi,
F2FS can be made to use fscrypt's queue for decryption and hence can reuse
"read callbacks" code for decrypting data.
For decompression, we could have a STEP_MISC where we invoke a FS provided
callback function for FS specific post read processing?
Something like the following can be implemented in read_callbacks(),
case STEP_MISC:
if (ctx->enabled_steps & (1 << STEP_MISC)) {
/*
ctx->fs_misc() must process bio in a workqueue
and later invoke read_callbacks() with
bio->bi_private's value as an argument.
*/
ctx->fs_misc(ctx->bio);
return;
}
ctx->cur_step++;
The fs_misc() callback can be passed in by the filesystem when invoking
read_callbacks_setup_bio().
--
chandan
next prev parent reply other threads:[~2019-08-19 13:31 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-08-16 6:17 [PATCH V4 0/8] Consolidate FS read I/O callbacks code Chandan Rajendra
2019-08-16 6:17 ` [PATCH V4 1/8] buffer_head: Introduce BH_Read_Cb flag Chandan Rajendra
2019-08-16 6:17 ` [PATCH V4 2/8] FS: Introduce read callbacks Chandan Rajendra
2019-08-16 6:17 ` [PATCH V4 3/8] fs/mpage.c: Integrate " Chandan Rajendra
2019-08-16 6:18 ` [PATCH V4 4/8] fs/buffer.c: add decryption support via read_callbacks Chandan Rajendra
2019-08-16 6:18 ` [PATCH V4 5/8] f2fs: Use read_callbacks for decrypting file data Chandan Rajendra
2019-08-18 13:45 ` [f2fs-dev] " Chao Yu
2019-08-19 13:33 ` Chandan Rajendra [this message]
2019-08-20 7:43 ` Chao Yu
2019-08-20 5:05 ` Chandan Rajendra
2019-08-20 5:12 ` Gao Xiang
2019-08-20 5:16 ` Gao Xiang
2019-08-20 16:25 ` Theodore Y. Ts'o
2019-08-20 17:07 ` Gao Xiang
2019-08-20 16:38 ` Theodore Y. Ts'o
2019-08-20 17:31 ` Jaegeuk Kim
2019-08-21 2:04 ` Chandan Rajendra
2019-08-16 6:18 ` [PATCH V4 6/8] ext4: Wire up ext4_readpage[s] to use mpage_readpage[s] Chandan Rajendra
2019-08-16 6:18 ` [PATCH V4 7/8] ext4: Enable encryption for subpage-sized blocks Chandan Rajendra
2019-08-16 6:18 ` [PATCH V4 8/8] fscrypt: remove struct fscrypt_ctx Chandan Rajendra
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=20104514.oSSJcvNEEM@localhost.localdomain \
--to=chandan@linux.ibm.com \
--cc=adilger.kernel@dilger.ca \
--cc=chandanrmail@gmail.com \
--cc=chao@kernel.org \
--cc=ebiggers@kernel.org \
--cc=hch@infradead.org \
--cc=jaegeuk@kernel.org \
--cc=linux-ext4@vger.kernel.org \
--cc=linux-f2fs-devel@lists.sourceforge.net \
--cc=linux-fscrypt@vger.kernel.org \
--cc=linux-fsdevel@vger.kernel.org \
--cc=tytso@mit.edu \
/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;
as well as URLs for NNTP newsgroup(s).