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

[Yohan Joung <jyh429@gmail.com>]

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  -
 		(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;
-- 
2.25.1