Re: [PATCH 01/20] rbd: define inbound data size for method ops

From: Josh Durgin <josh.durgin@inktank.com>
To: Alex Elder <elder@inktank.com>
Cc: "ceph-devel@vger.kernel.org" <ceph-devel@vger.kernel.org>
Subject: Re: [PATCH 01/20] rbd: define inbound data size for method ops
Date: Fri, 05 Apr 2013 11:13:37 -0700	[thread overview]
Message-ID: <515F1451.5010104@inktank.com> (raw)
In-Reply-To: <515ED92A.2010301@inktank.com>

Reviewed-by: Josh Durgin <josh.durgin@inktank.com>

On 04/05/2013 07:01 AM, Alex Elder wrote:
> When rbd creates an object request containing an object method call
> operation it is passing 0 for the size.  I originally thought this
> was because the length was not needed for method calls, but I think
> it really should be supplied, to describe how much space is
> available to receive response data.  So provide the supplied length.
>
> This resolves:
>      http://tracker.ceph.com/issues/4659
>
> Signed-off-by: Alex Elder <elder@inktank.com>
> ---
>   drivers/block/rbd.c |   13 ++++++-------
>   1 file changed, 6 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c
> index 9fb51b5..5e579fa 100644
> --- a/drivers/block/rbd.c
> +++ b/drivers/block/rbd.c
> @@ -1839,12 +1839,11 @@ static int rbd_obj_method_sync(struct rbd_device
> *rbd_dev,
>   	int ret;
>
>   	/*
> -	 * Method calls are ultimately read operations but they
> -	 * don't involve object data (so no offset or length).
> -	 * The result should placed into the inbound buffer
> -	 * provided.  They also supply outbound data--parameters for
> -	 * the object method.  Currently if this is present it will
> -	 * be a snapshot id.
> +	 * Method calls are ultimately read operations.  The result
> +	 * should placed into the inbound buffer provided.  They
> +	 * also supply outbound data--parameters for the object
> +	 * method.  Currently if this is present it will be a
> +	 * snapshot id.
>   	 */
>   	page_count = (u32) calc_pages_for(0, inbound_size);
>   	pages = ceph_alloc_page_vector(page_count, GFP_KERNEL);
> @@ -1852,7 +1851,7 @@ static int rbd_obj_method_sync(struct rbd_device
> *rbd_dev,
>   		return PTR_ERR(pages);
>
>   	ret = -ENOMEM;
> -	obj_request = rbd_obj_request_create(object_name, 0, 0,
> +	obj_request = rbd_obj_request_create(object_name, 0, inbound_size,
>   							OBJ_REQUEST_PAGES);
>   	if (!obj_request)
>   		goto out;
>