From: David Sterba <dsterba@suse.cz>
To: Josef Bacik <josef@toxicpanda.com>
Cc: linux-btrfs@vger.kernel.org, kernel-team@fb.com, stable@vger.kernel.org
Subject: Re: [PATCH] btrfs: save i_size in compress_file_range
Date: Wed, 23 Oct 2019 18:51:02 +0200 [thread overview]
Message-ID: <20191023165102.GC3001@twin.jikos.cz> (raw)
In-Reply-To: <20191011130354.8232-1-josef@toxicpanda.com>
On Fri, Oct 11, 2019 at 09:03:54AM -0400, Josef Bacik wrote:
> --- a/fs/btrfs/inode.c
> +++ b/fs/btrfs/inode.c
> @@ -474,6 +474,7 @@ static noinline int compress_file_range(struct async_chunk *async_chunk)
> u64 start = async_chunk->start;
> u64 end = async_chunk->end;
> u64 actual_end;
> + loff_t i_size = i_size_read(inode);
> int ret = 0;
> struct page **pages = NULL;
> unsigned long nr_pages;
> @@ -488,7 +489,13 @@ static noinline int compress_file_range(struct async_chunk *async_chunk)
> inode_should_defrag(BTRFS_I(inode), start, end, end - start + 1,
> SZ_16K);
>
> - actual_end = min_t(u64, i_size_read(inode), end + 1);
> + /*
> + * We need to save i_size before now because it could change in between
> + * us evaluating the size and assigning it. This is because we lock and
> + * unlock the page in truncate and fallocate, and then modify the i_size
> + * later on.
> + */
> + actual_end = min_t(u64, i_size, end + 1);
Ping. This is not a future proof fix, please update the changelog and
code according to the reply I sent.
next prev parent reply other threads:[~2019-10-23 16:50 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-10-11 13:03 [PATCH] btrfs: save i_size in compress_file_range Josef Bacik
2019-10-11 15:28 ` Filipe Manana
2019-10-11 17:15 ` Josef Bacik
2019-10-14 11:52 ` David Sterba
2019-10-23 16:51 ` David Sterba [this message]
2019-11-04 19:59 ` David Sterba
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=20191023165102.GC3001@twin.jikos.cz \
--to=dsterba@suse.cz \
--cc=josef@toxicpanda.com \
--cc=kernel-team@fb.com \
--cc=linux-btrfs@vger.kernel.org \
--cc=stable@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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox