[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <87v85xrmln.fsf@suse.de>
Date: Fri, 08 Mar 2024 11:26:12 +0000
From: Luis Henriques <lhenriques@...e.de>
To: Jan Kara <jack@...e.cz>
Cc: Ted Tso <tytso@....edu>, <linux-ext4@...r.kernel.org>
Subject: Re: [PATCH] ext4: Avoid excessive credit estimate in ext4_tmpfile()
Jan Kara <jack@...e.cz> writes:
> A user with minimum journal size (1024 blocks these days) complained
> about the following error triggered by generic/697 test in
> ext4_tmpfile():
>
> run fstests generic/697 at 2024-02-28 05:34:46
> JBD2: vfstest wants too many credits credits:260 rsv_credits:0 max:256
> EXT4-fs error (device loop0) in __ext4_new_inode:1083: error 28
>
> Indeed the credit estimate in ext4_tmpfile() is huge.
> EXT4_MAXQUOTAS_INIT_BLOCKS() is 219, then 10 credits from ext4_tmpfile()
> itself and then ext4_xattr_credits_for_new_inode() adds more credits
> needed for security attributes and ACLs. Now the
> EXT4_MAXQUOTAS_INIT_BLOCKS() is in fact unnecessary because we've
> already initialized quotas with dquot_init() shortly before and so
> EXT4_MAXQUOTAS_TRANS_BLOCKS() is enough (which boils down to 3 credits).
>
> Fixes: af51a2ac36d1 ("ext4: ->tmpfile() support")
> Signed-off-by: Jan Kara <jack@...e.cz>
FWIW, I've run generic/697 with a 1GiB device, with a block size of 65536.
Without this patch the test fails. Feel free to add my
Tested-by: Luis Henriques <lhenriques@...e.de>
Cheers,
--
Luís
> ---
> fs/ext4/namei.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
> index 05b647e6bc19..58fee3c6febc 100644
> --- a/fs/ext4/namei.c
> +++ b/fs/ext4/namei.c
> @@ -2898,7 +2898,7 @@ static int ext4_tmpfile(struct mnt_idmap *idmap, struct inode *dir,
> inode = ext4_new_inode_start_handle(idmap, dir, mode,
> NULL, 0, NULL,
> EXT4_HT_DIR,
> - EXT4_MAXQUOTAS_INIT_BLOCKS(dir->i_sb) +
> + EXT4_MAXQUOTAS_TRANS_BLOCKS(dir->i_sb) +
> 4 + EXT4_XATTR_TRANS_BLOCKS);
> handle = ext4_journal_current_handle();
> err = PTR_ERR(inode);
> --
>
> 2.35.3
>
Powered by blists - more mailing lists