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Date:   Tue, 10 Sep 2019 20:31:47 +1000
From:   Matthew Bobrowski <mbobrowski@mbobrowski.org>
To:     Ritesh Harjani <riteshh@linux.ibm.com>
Cc:     tytso@mit.edu, jack@suse.cz, adilger.kernel@dilger.ca,
        linux-ext4@vger.kernel.org, linux-fsdevel@vger.kernel.org,
        david@fromorbit.com, hch@infradead.org, darrick.wong@oracle.com
Subject: Re: [PATCH v2 5/6] ext4: introduce direct IO write path using iomap
 infrastructure
Message-ID: <20190910103147.GA10579@bobrowski>
References: <cover.1567978633.git.mbobrowski@mbobrowski.org>
 <7c2f0ee02b2659d5a45f3e30dbee66b443b5ea0a.1567978633.git.mbobrowski@mbobrowski.org>
 <20190909092617.07ECB42041@d06av24.portsmouth.uk.ibm.com>
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On Mon, Sep 09, 2019 at 02:56:15PM +0530, Ritesh Harjani wrote:
> On 9/9/19 4:49 AM, Matthew Bobrowski wrote:
> > +/*
> > + * For a write that extends the inode size, ext4_dio_write_iter() will
> > + * wait for the write to complete. Consequently, operations performed
> > + * within this function are still covered by the inode_lock().
> > + */
> Maybe add a comment that on success this returns 0.

OK, can do.

> > +static int ext4_dio_write_end_io(struct kiocb *iocb, ssize_t size, int error,
> > +				 unsigned int flags)
> > +{
> > +	int ret = 0;
> No need to initialize ret.
> 
> 
> > +	loff_t offset = iocb->ki_pos;
> > +	struct inode *inode = file_inode(iocb->ki_filp);
> > +
> > +	if (error) {
> > +		ret = ext4_handle_failed_inode_extension(inode, offset + size);
> > +		return ret ? ret : error;
> > +	}
> > +
> > +	if (flags & IOMAP_DIO_UNWRITTEN) {
> > +		ret = ext4_convert_unwritten_extents(NULL, inode,
> > +						     offset, size);
> > +		if (ret)
> > +			return ret;
> > +	}
> > +
> > +	if (offset + size > i_size_read(inode)) {
> > +		ret = ext4_handle_inode_extension(inode, offset, size, 0);
> > +		if (ret)
> > +			return ret;
> > +	}
> > +	return ret;
> Directly return 0, since if it falls here it mans it is a success case.
> You are anyway returning error from above error paths.

OK, sure.

--<M>--