[sheepdog] [PATCH] dog: use a minimum number of copies and zones for vdi checking

[Liu Yuan]

On Thu, Jan 16, 2014 at 06:10:04PM +0900, Hitoshi Mitake wrote:
> Current sheepdog allows the condition of a number of zones < a number
> of copies. But "dog vdi check" cannot handle the case well because it
> tries to create copies of lost/corrupted objects based on
> inode->nr_copies.
> 
> This patch lets "dog vdi check" create a minimum number of copies and
> zones.
> 
> Reported-by: Marcin Mirosław <marcin at mejor.pl>
> Signed-off-by: Hitoshi Mitake <mitake.hitoshi at lab.ntt.co.jp>
> ---
> 
> v3: handle a case of erasure coded VDIs
> 
> v2: renameing, zones_nr -> sd_zones_nr
> 
>  dog/vdi.c |   25 ++++++++++++++++++-------
>  1 file changed, 18 insertions(+), 7 deletions(-)
> 
> diff --git a/dog/vdi.c b/dog/vdi.c
> index 8fd4664..b6d382c 100644
> --- a/dog/vdi.c
> +++ b/dog/vdi.c
> @@ -1800,11 +1800,11 @@ static void vdi_check_object_main(struct work *work)
>  }
>  
>  static void queue_vdi_check_work(const struct sd_inode *inode, uint64_t oid,
> -				 uint64_t *done, struct work_queue *wq)
> +				 uint64_t *done, struct work_queue *wq,
> +				 int nr_copies)
>  {
>  	struct vdi_check_info *info;
>  	const struct sd_vnode *tgt_vnodes[SD_MAX_COPIES];
> -	int nr_copies = inode->nr_copies;
>  
>  	info = xzalloc(sizeof(*info) + sizeof(info->vcw[0]) * nr_copies);
>  	info->oid = oid;
> @@ -1830,6 +1830,7 @@ struct check_arg {
>  	const struct sd_inode *inode;
>  	uint64_t *done;
>  	struct work_queue *wq;
> +	int nr_copies;
>  };
>  
>  static void check_cb(void *data, enum btree_node_type type, void *arg)
> @@ -1844,7 +1845,8 @@ static void check_cb(void *data, enum btree_node_type type, void *arg)
>  			oid = vid_to_data_oid(ext->vdi_id, ext->idx);
>  			*(carg->done) = (uint64_t)ext->idx * SD_DATA_OBJ_SIZE;
>  			vdi_show_progress(*(carg->done), carg->inode->vdi_size);
> -			queue_vdi_check_work(carg->inode, oid, NULL, carg->wq);
> +			queue_vdi_check_work(carg->inode, oid, NULL, carg->wq,
> +					     carg->nr_copies);
>  		}
>  	}
>  }
> @@ -1855,8 +1857,15 @@ int do_vdi_check(const struct sd_inode *inode)
>  	uint64_t done = 0, oid;
>  	uint32_t vid;
>  	struct work_queue *wq;
> +	int nr_copies = min((int)inode->nr_copies, sd_zones_nr);
> +
> +	if (inode->copy_policy && sd_zones_nr < nr_copies) {
> +		sd_err("ABORT: Not enough active zones for consistency-checking"
> +		       " erasure coded VDI");

explicitly check inode->copy_policy == 1, since later we might add other policy.

> +		return EXIT_FAILURE;
> +	}
>  
> -	if (sd_nodes_nr < inode->nr_copies) {
> +	if (sd_nodes_nr < nr_copies) {

we should check sd_zones_nr < nr_copies as my previous mail suggested, no?

Thanks
Yuan