Re: [PATCH] btrfs: zoned: don't skip block group profile checks on conv zones

[Damien Le Moal <dlemoal@kernel.org>]

On 2/9/24 19:46, Johannes Thumshirn wrote:
> On a zoned filesystem with conventional zones, we're skipping the block
> group profile checks for the conventional zones.
> 
> This allows converting a zoned filesystem's data block groups to RAID when
> all of the zones backing the chunk are on conventional zones.  But this
> will lead to problems, once we're trying to allocate chunks backed by
> sequential zones.
> 
> So also check for conventional zones when loading a block group's profile
> on them.
> 
> Reported-by: 韩于惟 <hrx@bupt.moe>

Let's keep using the roman alphabet for names please...

Yuwei,

Not all kernel developers can read Chinese, so please sign your emails with your
name written in roman alphabet.

> Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
> ---
>  fs/btrfs/zoned.c | 30 +++++++++++++++++++++++++++---
>  1 file changed, 27 insertions(+), 3 deletions(-)
> 
> diff --git a/fs/btrfs/zoned.c b/fs/btrfs/zoned.c
> index d9716456bce0..5beb6b936e61 100644
> --- a/fs/btrfs/zoned.c
> +++ b/fs/btrfs/zoned.c
> @@ -1369,8 +1369,10 @@ static int btrfs_load_block_group_single(struct btrfs_block_group *bg,
>  		return -EIO;
>  	}
>  
> -	bg->alloc_offset = info->alloc_offset;
> -	bg->zone_capacity = info->capacity;
> +	if (info->alloc_offset != WP_CONVENTIONAL) {
> +		bg->alloc_offset = info->alloc_offset;
> +		bg->zone_capacity = info->capacity;
> +	}
>  	if (test_bit(0, active))
>  		set_bit(BLOCK_GROUP_FLAG_ZONE_IS_ACTIVE, &bg->runtime_flags);
>  	return 0;
> @@ -1406,6 +1408,16 @@ static int btrfs_load_block_group_dup(struct btrfs_block_group *bg,
>  		return -EIO;
>  	}
>  
> +	if (zone_info[0].alloc_offset == WP_CONVENTIONAL) {
> +		zone_info[0].alloc_offset = bg->alloc_offset;
> +		zone_info[0].capacity = bg->length;
> +	}
> +
> +	if (zone_info[1].alloc_offset == WP_CONVENTIONAL) {
> +		zone_info[1].alloc_offset = bg->alloc_offset;
> +		zone_info[1].capacity = bg->length;
> +	}
> +
>  	if (test_bit(0, active) != test_bit(1, active)) {
>  		if (!btrfs_zone_activate(bg))
>  			return -EIO;
> @@ -1458,6 +1470,9 @@ static int btrfs_load_block_group_raid1(struct btrfs_block_group *bg,
>  						 zone_info[1].capacity);
>  	}
>  
> +	if (zone_info[0].alloc_offset == WP_CONVENTIONAL)
> +		zone_info[0].alloc_offset = bg->alloc_offset;
> +
>  	if (zone_info[0].alloc_offset != WP_MISSING_DEV)
>  		bg->alloc_offset = zone_info[0].alloc_offset;
>  	else
> @@ -1479,6 +1494,11 @@ static int btrfs_load_block_group_raid0(struct btrfs_block_group *bg,
>  		return -EINVAL;
>  	}
>  
> +	for (int i = 0; i < map->num_stripes; i++) {
> +		if (zone_info[i].alloc_offset == WP_CONVENTIONAL)
> +			zone_info[i].alloc_offset = bg->alloc_offset;
> +	}
> +
>  	for (int i = 0; i < map->num_stripes; i++) {
>  		if (zone_info[i].alloc_offset == WP_MISSING_DEV ||
>  		    zone_info[i].alloc_offset == WP_CONVENTIONAL)
> @@ -1511,6 +1531,11 @@ static int btrfs_load_block_group_raid10(struct btrfs_block_group *bg,
>  		return -EINVAL;
>  	}
>  
> +	for (int i = 0; i < map->num_stripes; i++) {
> +		if (zone_info[i].alloc_offset == WP_CONVENTIONAL)
> +			zone_info[i].alloc_offset = bg->alloc_offset;
> +	}
> +
>  	for (int i = 0; i < map->num_stripes; i++) {
>  		if (zone_info[i].alloc_offset == WP_MISSING_DEV ||
>  		    zone_info[i].alloc_offset == WP_CONVENTIONAL)
> @@ -1605,7 +1630,6 @@ int btrfs_load_block_group_zone_info(struct btrfs_block_group *cache, bool new)
>  		} else if (map->num_stripes == num_conventional) {
>  			cache->alloc_offset = last_alloc;
>  			set_bit(BLOCK_GROUP_FLAG_ZONE_IS_ACTIVE, &cache->runtime_flags);
> -			goto out;
>  		}
>  	}
>  

-- 
Damien Le Moal
Western Digital Research