f2fs: zone: fix to calculate first_zoned_segno correctly

[ Upstream commit dc6d9ef5 ]

A zoned device can has both conventional zones and sequential zones,
so we should not treat first segment of zoned device as first_zoned_segno,
instead, we need to check zone type for each zone during traversing zoned
device to find first_zoned_segno.

Otherwise, for below case, first_zoned_segno will be 0, which could be
wrong.

create_null_blk 512 2 1024 1024
mkfs.f2fs -m /dev/nullb0

Testcase:

export SCRIPTS_PATH=/share/git/scripts

test multiple devices w/ zoned device
for ((i=0;i<8;i++)) do {
	zonesize=$((2<<$i))
	conzone=$((4096/$zonesize))
	seqzone=$((4096/$zonesize))
	$SCRIPTS_PATH/nullblk_create.sh 512 $zonesize $conzone $seqzone
	mkfs.f2fs -f -m /dev/vdb -c /dev/nullb0
	mount /dev/vdb /mnt/f2fs
	touch /mnt/f2fs/file
	f2fs_io pinfile set /mnt/f2fs/file $((8589934592*2))
	stat /mnt/f2fs/file
	df
	cat /proc/fs/f2fs/vdb/segment_info
	umount /mnt/f2fs
	$SCRIPTS_PATH/nullblk_remove.sh 0
} done

test single zoned device
for ((i=0;i<8;i++)) do {
	zonesize=$((2<<$i))
	conzone=$((4096/$zonesize))
	seqzone=$((4096/$zonesize))
	$SCRIPTS_PATH/nullblk_create.sh 512 $zonesize $conzone $seqzone
	mkfs.f2fs -f -m /dev/nullb0
	mount /dev/nullb0 /mnt/f2fs
	touch /mnt/f2fs/file
	f2fs_io pinfile set /mnt/f2fs/file $((8589934592*2))
	stat /mnt/f2fs/file
	df
	cat /proc/fs/f2fs/nullb0/segment_info
	umount /mnt/f2fs
	$SCRIPTS_PATH/nullblk_remove.sh 0
} done

Fixes: 9703d69d ("f2fs: support file pinning for zoned devices")
Cc: Daeho Jeong <daehojeong@google.com>
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>