Re: [PATCH v10 12/41] btrfs: implement zoned chunk allocator

[Anand Jain <anand.jain@oracle.com>]

> diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
> index db884b96a5ea..7831cf6c6da4 100644
> --- a/fs/btrfs/volumes.c
> +++ b/fs/btrfs/volumes.c
> @@ -1416,6 +1416,21 @@ static bool contains_pending_extent(struct btrfs_device *device, u64 *start,
>   	return false;
>   }
>   
> +static inline u64 dev_extent_search_start_zoned(struct btrfs_device *device,
> +						u64 start)
> +{
> +	u64 tmp;
> +
> +	if (device->zone_info->zone_size > SZ_1M)
> +		tmp = device->zone_info->zone_size;
> +	else
> +		tmp = SZ_1M;
> +	if (start < tmp)
> +		start = tmp;
> +
> +	return btrfs_align_offset_to_zone(device, start);
> +}
> +
>   static u64 dev_extent_search_start(struct btrfs_device *device, u64 start)
>   {
>   	switch (device->fs_devices->chunk_alloc_policy) {
> @@ -1426,11 +1441,57 @@ static u64 dev_extent_search_start(struct btrfs_device *device, u64 start)
>   		 * make sure to start at an offset of at least 1MB.
>   		 */
>   		return max_t(u64, start, SZ_1M);
> +	case BTRFS_CHUNK_ALLOC_ZONED:
> +		return dev_extent_search_start_zoned(device, start);
>   	default:
>   		BUG();
>   	}
>   }
>   

> @@ -165,4 +190,13 @@ static inline bool btrfs_check_super_location(struct btrfs_device *device,
>   	       !btrfs_dev_is_sequential(device, pos);
>   }
>   
> +static inline u64 btrfs_align_offset_to_zone(struct btrfs_device *device,
> +					     u64 pos)
> +{
> +	if (!device->zone_info)
> +		return pos;
> +
> +	return ALIGN(pos, device->zone_info->zone_size);
> +}
> +
>   #endif
> 

  Small functions (such as above) can be opened coded to make the
  reviewing easier. The btrfs_align_offset_to_zone() and
  dev_extent_search_start_zoned() can be open coded and merged into
  the parent function dev_extent_search_start() as below...

dev_extent_search_start()
::
	case BTRFS_CHUNK_ALLOC_ZONED:
		start = max_t(u64, start,
			      max_t(u64, device->zone_info->zone_size, SZ_1M));

          return ALIGN(start, device->zone_info->zone_size);

  As of now we don't allow mix of zoned with regular device in a
  btrfs (those are verified during mount and device add/replace).
  So we don't have to check for the same again in
  btrfs_align_offset_to_zone().

Thanks.