Re: [PATCH] f2fs: fix to cover allocate_segment() with lock

[Chao Yu]

On 2021/4/20 0:57, Jaegeuk Kim wrote:
> On 04/14, Chao Yu wrote:
> > As we did for other cases, in fix_curseg_write_pointer(), let's
> > change as below:
> > - use callback function s_ops->allocate_segment() instead of
> > raw function allocate_segment_by_default();
> > - cover allocate_segment() with curseg_lock and sentry_lock.
> >
> > Signed-off-by: Chao Yu <yuchao0@xxxxxxxxxx>
> > ---
> >   fs/f2fs/segment.c | 7 ++++++-
> >   1 file changed, 6 insertions(+), 1 deletion(-)
> >
> > diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
> > index b2ee6b7791b0..daf9531ec58f 100644
> > --- a/fs/f2fs/segment.c
> > +++ b/fs/f2fs/segment.c
> > @@ -4848,7 +4848,12 @@ static int fix_curseg_write_pointer(struct f2fs_sb_info *sbi, int type)
> >   
> >   	f2fs_notice(sbi, "Assign new section to curseg[%d]: "
> >   		    "curseg[0x%x,0x%x]", type, cs->segno, cs->next_blkoff);
> > -	allocate_segment_by_default(sbi, type, true);
> > +
> > +	down_read(&SM_I(sbi)->curseg_lock);
> > +	down_write(&SIT_I(sbi)->sentry_lock);
> > +	SIT_I(sbi)->s_ops->allocate_segment(sbi, type, true);
> > +	up_write(&SIT_I(sbi)->sentry_lock);
> > +	up_read(&SM_I(sbi)->curseg_lock);
>
> Seems f2fs_allocate_new_section()?

f2fs_allocate_new_section() will allocate new section only when current
section has been initialized and has valid block/ckpt_block.

It looks fix_curseg_write_pointer() wants to force migrating current segment
to new section whenever write pointer and curseg->next_blkoff is inconsistent.

So how about adding a parameter to force f2fs_allocate_new_section() to
allocate new section?

Thanks,

> >   
> >   	/* check consistency of the zone curseg pointed to */
> >   	if (check_zone_write_pointer(sbi, zbd, &zone))
> > --
> > 2.29.2
> .