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

[Daeho Jeong]

On Thu, Jan 25, 2024 at 5:27 PM Chao Yu <chao@xxxxxxxxxx> wrote:
>
> On 2024/1/26 0:25, Daeho Jeong wrote:
> > On Wed, Jan 24, 2024 at 7:34 PM Chao Yu <chao@xxxxxxxxxx> 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;

> 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@xxxxxxxxxx>
> >>>
> >>> Make to allocate logs after conventional area for HM zoned devices to
> >>> spare them for file pinning support.
> >>>
> >>> Signed-off-by: Daeho Jeong <daehojeong@xxxxxxxxxx>
> >>> ---
> >>>    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);