Re: [PATCH 3/4] DDF: ddf_process_update: delete removed disks from dlist

[Martin Wilck <mwilck@arcor.de>]

Neil,

This calls free() from monitor context - I am not certain if that's
allowed and if no, what alternative there might be.

Martin

On 08/02/2013 12:35 AM, mwilck@arcor.de wrote:
> We currently remove Failed disks that aren't used by any VD.
> If we do that, we need to remove the disks from the dlist as well.
> Otherwise, the same pdnum may occur multiple times in the dlist.
> 
> This fixes the problem reported by Albert Pauw.
> 
> Signed-off-by: Martin Wilck <mwilck@arcor.de>
> ---
>  super-ddf.c |   25 ++++++++++++++++++++++---
>  1 files changed, 22 insertions(+), 3 deletions(-)
> 
> diff --git a/super-ddf.c b/super-ddf.c
> index 7a7f5fe..e1d0509 100644
> --- a/super-ddf.c
> +++ b/super-ddf.c
> @@ -4366,6 +4366,19 @@ static void copy_matching_bvd(struct ddf_super *ddf,
>  	       conf->sec_elmnt_seq, guid_str(conf->guid));
>  }
>  
> +static void _delete_dl_by_refnum(struct ddf_super *ddf, be32 refnum)
> +{
> +	struct dl **pdl = &ddf->dlist, *d;
> +	while (*pdl) {
> +		if (be32_eq((*pdl)->disk.refnum, refnum)) {
> +			d = *pdl;
> +			*pdl = d->next;
> +			free(d);
> +		} else
> +			pdl = &(*pdl)->next;
> +	}
> +}
> +
>  static void ddf_process_update(struct supertype *st,
>  			       struct metadata_update *update)
>  {
> @@ -4638,9 +4651,15 @@ static void ddf_process_update(struct supertype *st,
>  			if (be16_and(ddf->phys->entries[pdnum].state,
>  				     cpu_to_be16(DDF_Failed))
>  			    && be16_and(ddf->phys->entries[pdnum].state,
> -					cpu_to_be16(DDF_Transition)))
> -				/* skip this one */;
> -			else if (pdnum == pd2)
> +					cpu_to_be16(DDF_Transition))) {
> +				/* skip this one and remove from dlist */
> +				dprintf("%s: %08x no longer used, removing it\n",
> +					__func__,
> +					be32_to_cpu(ddf->phys->
> +						    entries[pdnum].refnum));
> +				_delete_dl_by_refnum(
> +					ddf, ddf->phys->entries[pdnum].refnum);
> +			} else if (pdnum == pd2)
>  				pd2++;
>  			else {
>  				ddf->phys->entries[pd2] =