Re: [PATCH v2] mkfs.f2fs: adjust zone alignment when using convention partition with zoned one

[Chao Yu <chao@kernel.org>]

On 2024/10/29 21:45, Yohan Joung wrote:
> When formatting conventional partition with zoned one, we are already
> aligning the starting block address of the next device to the zone size.
> Therefore, we do not align the segment0 address to the zone alignment.
> This reduces the wasted zone_align_start_offset.
> 
> Test result
> segment0 blkaddr 389583 -> 119251
> Add one additional section to main
> 
> Signed-off-by: Yohan Joung <yohan.joung@sk.com>
> ---
>   mkfs/f2fs_format.c | 10 +++++++---
>   1 file changed, 7 insertions(+), 3 deletions(-)
> 
> diff --git a/mkfs/f2fs_format.c b/mkfs/f2fs_format.c
> index a01b19e..52a1e18 100644
> --- a/mkfs/f2fs_format.c
> +++ b/mkfs/f2fs_format.c
> @@ -266,6 +266,7 @@ static int f2fs_prepare_super_block(void)
>   	uint32_t log_sectorsize, log_sectors_per_block;
>   	uint32_t log_blocksize, log_blks_per_seg;
>   	uint32_t segment_size_bytes, zone_size_bytes;
> +	uint32_t alignment_bytes;
>   	uint32_t sit_segments, nat_segments;
>   	uint32_t blocks_for_sit, blocks_for_nat, blocks_for_ssa;
>   	uint32_t total_valid_blks_available;
> @@ -305,10 +306,12 @@ static int f2fs_prepare_super_block(void)
>   
>   	set_sb(block_count, c.total_sectors >> log_sectors_per_block);
>   
> +	alignment_bytes = c.zoned_mode && c.ndevs > 1 ? segment_size_bytes : zone_size_bytes;
> +
>   	zone_align_start_offset =
>   		((uint64_t) c.start_sector * DEFAULT_SECTOR_SIZE +
> -		2 * F2FS_BLKSIZE + zone_size_bytes - 1) /
> -		zone_size_bytes * zone_size_bytes -
> +		2 * F2FS_BLKSIZE + alignment_bytes  - 1) /
> +		alignment_bytes  * alignment_bytes  -

round_up(..., alignment_bytes) * alignment_bytes - ?

Otherwise, it looks good to me.

Reviewed-by: Chao Yu <chao@kernel.org>

Thanks,

>   		(uint64_t) c.start_sector * DEFAULT_SECTOR_SIZE;
>   
>   	if (c.feature & F2FS_FEATURE_RO)
> @@ -327,7 +330,8 @@ static int f2fs_prepare_super_block(void)
>   
>   	if (c.zoned_mode && c.ndevs > 1)
>   		zone_align_start_offset +=
> -			(c.devices[0].total_sectors * c.sector_size) % zone_size_bytes;
> +			(c.devices[0].total_sectors * c.sector_size -
> +			 zone_align_start_offset) % zone_size_bytes;
>   
>   	set_sb(segment0_blkaddr, zone_align_start_offset / blk_size_bytes);
>   	sb->cp_blkaddr = sb->segment0_blkaddr;