[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <alpine.LFD.2.00.1201201308510.7115@dhcp-27-109.brq.redhat.com>
Date: Fri, 20 Jan 2012 13:09:37 +0100 (CET)
From: Lukas Czerner <lczerner@...hat.com>
To: "Ted Ts'o" <tytso@....edu>
cc: Lukas Czerner <lczerner@...hat.com>, linux-ext4@...r.kernel.org,
Eric Sandeen <sandeen@...hat.com>
Subject: Re: [PATCH v2] ext4: ignore EXT4_INODE_JOURNAL_DATA flag with
delalloc
On Thu, 19 Jan 2012, Ted Ts'o wrote:
> On Thu, Jan 12, 2012 at 12:03:44PM +0100, Lukas Czerner wrote:
> > + /* We do not support data journalling with delayed allocation */
> > + if (!S_ISREG(inode->i_mode) ||
> > + (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) ||
> > + (ext4_test_inode_flag(inode, EXT4_INODE_JOURNAL_DATA) &&
> > + !test_opt(inode->i_sb, DELALLOC)))
> > + return EXT4_INODE_JOURNAL_DATA_MODE; /* journal data */
>
> It's probably clearer to make avoid the complex boolean expression:
>
> if (!S_ISREG(inode->i_mode))
> return EXT4_INODE_JOURNAL_DATA_MODE;
> if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA))
> return EXT4_INODE_JOURNAL_DATA_MODE;
> if (ext4_test_inode_flag(inode, EXT4_INODE_JOURNAL_DATA) &&
> !test_opt(inode->i_sb, DELALLOC)))
> return EXT4_INODE_JOURNAL_DATA_MODE;
>
> You could combine the first two condiionals:
>
> if (!S_ISREG(inode->i_mode) ||
> test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
> return EXT4_INODE_JOURNAL_DATA_MODE;
> if (ext4_test_inode_flag(inode, EXT4_INODE_JOURNAL_DATA) &&
> !test_opt(inode->i_sb, DELALLOC)))
> return EXT4_INODE_JOURNAL_DATA_MODE;
>
> ... but combining || and && where someone has to squint and count
> parenthesis can be error-prone. I can look at either of the above two
> and understand quickly what's going on. With what you had (especially
> since the identation of !test_opt(...) wasn't quite right, I had to
> squint and think for a bit before I convince dmyself it was correct.
>
> Otherwise, looks good!
>
> - Ted
Thanks Ted, you're right it is much clearer this way. I'll resend the
patch.
-Lukas
--
To unsubscribe from this list: send the line "unsubscribe linux-ext4" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Powered by blists - more mailing lists