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Date: Sun, 16 May 2010 09:38:20 -0400
From: Christoph Hellwig <hch@infradead.org>
To: Jiaying Zhang <jiayingz@google.com>
Cc: hch@infradead.org, jens.axboe@oracle.com, linux-kernel@vger.kernel.org,
       mrubin@google.com
Subject: Re: [PATCH, RFC] addjust discard request to be aligned with hwsect
	size to support SSDs with larger sector size
Message-ID: <20100516133820.GA25820@infradead.org>
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On Wed, May 12, 2010 at 10:19:53PM -0700, Jiaying Zhang wrote:
> The currect blkdev_issue_discard() function assumes 512 sector size.
> We have seen some problem when using discard on a SSD that has larger
> sector size. The following patch adjusts the starting address and size of
> a discard request to be aligned with hwsect size.

Looks good,


Reviewed-by: Christoph Hellwig <hch@lst.de>

> -	if (!blk_queue_discard(q))
> +	if (!blk_queue_discard(q) || q->limits.max_discard_sectors == 0)
>  		return -EOPNOTSUPP;

But this change is unrelated.  It's fine with me, but needs a patch of
it's own with a proper description.