[sheepdog] [PATCH] sheep: split create_vdi_obj() into 4 functions

[Liu Yuan]

On Thu, Aug 22, 2013 at 04:53:48PM +0900, MORITA Kazutaka wrote:
> From: MORITA Kazutaka <morita.kazutaka at lab.ntt.co.jp>
> 
> create_vdi_obj() is very complex because it contains four kinds of
> operations:
> 
>  - create fresh vdi
>  - clone vdi
>  - snapshot vdi
>  - rebase vdi (rollback)
> 
> Splitting them apart make the code much easier to read.
> 
> This patch is just a cleanup and doesn't change its logic at all.
> 
> Signed-off-by: MORITA Kazutaka <morita.kazutaka at lab.ntt.co.jp>
> ---
>  sheep/ops.c        |   10 +-
>  sheep/sheep_priv.h |    4 +-
>  sheep/vdi.c        |  356 ++++++++++++++++++++++++++++++++++++++--------------
>  3 files changed, 277 insertions(+), 93 deletions(-)
> 
> diff --git a/sheep/ops.c b/sheep/ops.c
> index 4c0f975..76ff611 100644
> --- a/sheep/ops.c
> +++ b/sheep/ops.c
> @@ -67,6 +67,10 @@ static int cluster_new_vdi(struct request *req)
>  	struct sd_rsp *rsp = &req->rp;
>  	uint32_t vid;
>  	int ret;
> +	struct timeval tv;
> +
> +	gettimeofday(&tv, NULL);
> +
>  	struct vdi_iocb iocb = {
>  		.name = req->data,
>  		.data_len = hdr->data_length,
> @@ -75,12 +79,16 @@ static int cluster_new_vdi(struct request *req)
>  		.create_snapshot = !!hdr->vdi.snapid,
>  		.nr_copies = hdr->vdi.copies ? hdr->vdi.copies :
>  				sys->cinfo.nr_copies,
> +		.time = (uint64_t) tv.tv_sec << 32 | tv.tv_usec * 1000,
>  	};
>  
>  	if (hdr->data_length != SD_MAX_VDI_LEN)
>  		return SD_RES_INVALID_PARMS;
>  
> -	ret = vdi_create(&iocb, &vid);
> +	if (iocb.create_snapshot)
> +		ret = sd_snapshot_create(&iocb, &vid);
> +	else
> +		ret = sd_vdi_create(&iocb, &vid);
>  
>  	rsp->vdi.vdi_id = vid;
>  	rsp->vdi.copies = iocb.nr_copies;
> diff --git a/sheep/sheep_priv.h b/sheep/sheep_priv.h
> index 35c067e..b78afc8 100644
> --- a/sheep/sheep_priv.h
> +++ b/sheep/sheep_priv.h
> @@ -171,6 +171,7 @@ struct vdi_iocb {
>  	uint32_t snapid;
>  	bool create_snapshot;
>  	int nr_copies;
> +	uint64_t time;
>  };
>  
>  struct vdi_info {
> @@ -276,7 +277,8 @@ int get_max_copy_number(void);
>  int get_req_copy_number(struct request *req);
>  int add_vdi_state(uint32_t vid, int nr_copies, bool snapshot);
>  int vdi_exist(uint32_t vid);
> -int vdi_create(struct vdi_iocb *iocb, uint32_t *new_vid);
> +int sd_vdi_create(struct vdi_iocb *iocb, uint32_t *new_vid);
> +int sd_snapshot_create(struct vdi_iocb *iocb, uint32_t *new_vid);

sd_{vdi,snapshot}_create share almost the same logic, how about merge them
into one function? Either ask sd_{vdi,snapshot}_create call the shared helper
or use single sd_vdi_create() function

Thanks
Yuan