Re: [PATCH 2/5] Add raid1->raid0 takeover support

[Neil Brown <neilb@suse.de>]

On Mon, 24 Jan 2011 15:17:12 +0100
Krzysztof Wojcik <krzysztof.wojcik@intel.com> wrote:

> Add support for raid1 to raid0 takeover operation in user space.
> This patch includes support for native and imsm metadata.
> 
> Signed-off-by: Krzysztof Wojcik <krzysztof.wojcik@intel.com>
> ---
>  Grow.c        |   39 ++++++++++++++++++++++++++++-----------
>  super-intel.c |    6 ++++++
>  2 files changed, 34 insertions(+), 11 deletions(-)
> 
> diff --git a/Grow.c b/Grow.c
> index 7c5edae..a8da20a 100644
> --- a/Grow.c
> +++ b/Grow.c
> @@ -650,15 +650,20 @@ void abort_reshape(struct mdinfo *sra)
>  	sysfs_set_str(sra, NULL, "sync_max", "max");
>  }
>  
> -int remove_disks_on_raid10_to_raid0_takeover(struct supertype *st,
> -					     struct mdinfo *sra,
> -					     int layout)
> +int remove_disks_for_takeover(struct supertype *st,
> +			     struct mdinfo *sra,
> +			     int layout)
>  {
>  	int nr_of_copies;
>  	struct mdinfo *remaining;
>  	int slot;
>  
> -	nr_of_copies = layout & 0xff;
> +	if (sra->array.level == 10)
> +		nr_of_copies = layout & 0xff;
> +	else if (sra->array/level == 1)
> +		nr_of_copies = sra->array.raid_disks;
> +	else
> +		return 1;
>  
>  	remaining = sra->devs;
>  	sra->devs = NULL;
> @@ -911,8 +916,18 @@ char *analyse_change(struct mdinfo *info, struct
> reshape *re) switch (info->array.level) {
>  	case 1:
>  		/* RAID1 can convert to RAID1 with different disks,
> or
> -		 * raid5 with 2 disks
> +		 * raid5 with 2 disks, or
> +		 * raid0 with 1 disk
>  		 */
> +		if (info->new_level == 0) {
> +			re->level = 0;
> +			re->before.data_disks =
> info->array.raid_disks / 2;
> +			re->after.data_disks = re->before.data_disks;

dividing raid_disks by 2 doesn't make any sense at all.
It have fixed it so that it does make sense, and applied.

Thanks,
NeilBrown


> +			re->before.layout = 0;
> +			re->backup_blocks = 0;
> +			re->parity = 0;
> +			return NULL;
> +		}
>  		if (info->new_level == 1) {
>  			if (info->delta_disks == UnSet)
>  				/* Don't know what to do */
> @@ -1449,15 +1464,17 @@ int Grow_reshape(char *devname, int fd, int
> quiet, char *backup_file, size = array.size;
>  	}
>  
> -	/* ========= check for Raid10 -> Raid0 conversion
> ===============
> +	/* ========= check for Raid10/Raid1 -> Raid0 conversion
> ===============
>  	 * current implementation assumes that following conditions
> must be met:
> -	 * - far_copies == 1
> -	 * - near_copies == 2
> +	 * - RAID10:
> +	 * 	- far_copies == 1
> +	 * 	- near_copies == 2
>  	 */
> -	if (level == 0 && array.level == 10 && sra &&
> -	    array.layout == ((1 << 8) + 2) && !(array.raid_disks &
> 1)) {
> +	if ((level == 0 && array.level == 10 && sra &&
> +	    array.layout == ((1 << 8) + 2) && !(array.raid_disks &
> 1)) ||
> +	    (level == 0 && array.level == 1 && sra)) {
>  		int err;
> -		err = remove_disks_on_raid10_to_raid0_takeover(st,
> sra, array.layout);
> +		err = remove_disks_for_takeover(st, sra,
> array.layout); if (err) {
>  			dprintf(Name": Array cannot be reshaped\n");
>  			if (cfd > -1)
> diff --git a/super-intel.c b/super-intel.c
> index b25d4fb..461fb0c 100644
> --- a/super-intel.c
> +++ b/super-intel.c
> @@ -6785,6 +6785,12 @@ enum imsm_reshape_type
> imsm_analyze_change(struct supertype *st, check_devs = 1;
>  			}
>  			break;
> +		case 1:
> +			if (geo->level == 0) {
> +				change = CH_TAKEOVER;
> +				check_devs = 1;
> +			}
> +			break;
>  		case 5:
>  			if (geo->level != 0)
>  				change = CH_LEVEL_MIGRATION;
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-raid"
> in the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html