Re: [f2fs-dev] [PATCH] f2fs-tools: allocate logs after conventional area for HM zoned devices

[Yongpeng Yang <yangyongpeng1@oppo.com>]

cur_seg[CURSEG_COLD_DATA] will exceed end boundary of main area when:
device[1]: zone device size = [2 MB ~ 10MB]

So, if there are not enough seq zones for six cursegs, we should still 
assign 0 to c.cur_seg[CURSEG_HOT_NODE] or reserve several conv zones for 
cursegs.

On 1/29/2024 11:47 PM, Daeho Jeong wrote:
> On Sun, Jan 28, 2024 at 5:27 PM Chao Yu <chao@kernel.org> wrote:
>>
>> On 2024/1/27 2:17, Daeho Jeong wrote:
>>> On Thu, Jan 25, 2024 at 5:27 PM Chao Yu <chao@kernel.org> wrote:
>>>>
>>>> On 2024/1/26 0:25, Daeho Jeong wrote:
>>>>> On Wed, Jan 24, 2024 at 7:34 PM Chao Yu <chao@kernel.org> wrote:
>>>>>>
>>>>>> +Cc Yongpeng Yang
>>>>>>
>>>>>> Daeho,
>>>>>>
>>>>>> Yongpeng reports a potential issue: if c.devices[0].total_segments is
>>>>>> larger than segments of mainarea, c.cur_seg[CURSEG_HOT_NODE] will exceed
>>>>>> end boundary of mainarea. Could you please check that? though it's a corner
>>>>>> case.
>>>>>
>>>>> Can you elaborate more?
>>>>
>>>> Since c.cur_seg[CURSEG_HOT_NODE] is an offset started from main_blkaddr.
>>>
>>> Oh, Got it.
>>> Then, how about this?
>>>
>>>            c.cur_seg[CURSEG_HOT_NODE] = c.zoned_model == F2FS_ZONED_HM ?
>>>                            (c.devices[1].start_blkaddr -
>>> get_sb(main_blkaddr)) / c.blks_per_seg : 0;
>>
>> Better, but log header should align to start blkaddr of zone?
> 
> It's already aligned here.
> 
>          if (c.zoned_mode && c.ndevs > 1)
>                  zone_align_start_offset +=
>                          (c.devices[0].total_sectors * c.sector_size) %
> zone_size_bytes;
> 
> ...
> 
>          for (i = 0; i < c.ndevs; i++) {
>                  if (i == 0) {
>                          c.devices[i].total_segments =
>                                  (c.devices[i].total_sectors *
>                                  c.sector_size - zone_align_start_offset) /
>                                  segment_size_bytes;
>                          c.devices[i].start_blkaddr = 0;
>                          c.devices[i].end_blkaddr = c.devices[i].total_segments *
>                                                  c.blks_per_seg - 1 +
>                                                  sb->segment0_blkaddr;
>                  } else {
>                          c.devices[i].total_segments =
>                                  c.devices[i].total_sectors /
>                                  (c.sectors_per_blk * c.blks_per_seg);
>                          c.devices[i].start_blkaddr =
>                                          c.devices[i - 1].end_blkaddr + 1;
> 
> ...
> 
>          total_meta_zones = ZONE_ALIGN(total_meta_segments *
>                                                  c.blks_per_seg);
> 
>          set_sb(main_blkaddr, get_sb(segment0_blkaddr) + total_meta_zones *
>                                  c.segs_per_zone * c.blks_per_seg);
> 
>>
>> Thanks,
>>
>>>
>>>> If c.cur_seg[CURSEG_HOT_NODE] was assigned w/ c.devices[0].total_segments,
>>>> and c.devices[0].total_segments is larger than segments of mainare,
>>>> c.cur_seg[CURSEG_HOT_NODE] will exceed the end boundary of mainarea.
>>>>
>>>>           c.cur_seg[CURSEG_HOT_NODE] = c.zoned_model == F2FS_ZONED_HM ?
>>>>                           c.devices[0].total_segments : 0;
>>>>
>>>>> In the case of F2FS_ZONED_HM, we have the devices[1].
>>>>> Do you mean the case we format the filesystem intentionally smaller
>>>>> than what devices have?
>>>>
>>>> I mean blew case:
>>>> device[0]: conventional device size = 10240 MB
>>>> device[1]: zone device size = 2 MB
>>>>
>>>> Thanks,
>>>>
>>>>>
>>>>>>
>>>>>> On 2024/1/18 7:00, Daeho Jeong wrote:
>>>>>>> From: Daeho Jeong <daehojeong@google.com>
>>>>>>>
>>>>>>> Make to allocate logs after conventional area for HM zoned devices to
>>>>>>> spare them for file pinning support.
>>>>>>>
>>>>>>> Signed-off-by: Daeho Jeong <daehojeong@google.com>
>>>>>>> ---
>>>>>>>      mkfs/f2fs_format.c | 3 ++-
>>>>>>>      1 file changed, 2 insertions(+), 1 deletion(-)
>>>>>>>
>>>>>>> diff --git a/mkfs/f2fs_format.c b/mkfs/f2fs_format.c
>>>>>>> index f2840c8..91a7f4b 100644
>>>>>>> --- a/mkfs/f2fs_format.c
>>>>>>> +++ b/mkfs/f2fs_format.c
>>>>>>> @@ -557,7 +557,8 @@ static int f2fs_prepare_super_block(void)
>>>>>>>                  c.cur_seg[CURSEG_COLD_DATA] = 0;
>>>>>>>                  c.cur_seg[CURSEG_WARM_DATA] = next_zone(CURSEG_COLD_DATA);
>>>>>>>          } else if (c.zoned_mode) {
>>>>>>> -             c.cur_seg[CURSEG_HOT_NODE] = 0;
>>>>>>> +             c.cur_seg[CURSEG_HOT_NODE] = c.zoned_model == F2FS_ZONED_HM ?
>>>>>>> +                     c.devices[0].total_segments : 0;
>>>>>>>                  c.cur_seg[CURSEG_WARM_NODE] = next_zone(CURSEG_HOT_NODE);
>>>>>>>                  c.cur_seg[CURSEG_COLD_NODE] = next_zone(CURSEG_WARM_NODE);
>>>>>>>                  c.cur_seg[CURSEG_HOT_DATA] = next_zone(CURSEG_COLD_NODE);