Re: [PATCH v2 4/4] f2fs: stop checkpoint when get a out-of-bounds segment

[Chao Yu]

On 2024/2/8 8:16, Jaegeuk Kim wrote:
> On 02/07, Zhiguo Niu wrote:
> > There is low probability that an out-of-bounds segment will be got
> > on a small-capacity device. In order to prevent subsequent write requests
> > allocating block address from this invalid segment, which may cause
> > unexpected issue, stop checkpoint should be performed.
> >
> > Also introduce a new stop cp reason:  STOP_CP_REASON_OUTOF_RAGNE.
>
> OUT_OF_RANGE?

Maybe STOP_CP_REASON_NO_SEGMENT will be more explicit?

Thanks,

> > Signed-off-by: Zhiguo Niu <zhiguo.niu@xxxxxxxxxx>
> > ---
> >   fs/f2fs/segment.c       | 12 ++++++++++--
> >   include/linux/f2fs_fs.h |  1 +
> >   2 files changed, 11 insertions(+), 2 deletions(-)
> >
> > diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
> > index 6772ad4..6fe2baf 100644
> > --- a/fs/f2fs/segment.c
> > +++ b/fs/f2fs/segment.c
> > @@ -2666,7 +2666,11 @@ static void get_new_segment(struct f2fs_sb_info *sbi,
> >   		if (dir == ALLOC_RIGHT) {
> >   			secno = find_first_zero_bit(free_i->free_secmap,
> >   							MAIN_SECS(sbi));
> > -			f2fs_bug_on(sbi, secno >= MAIN_SECS(sbi));
> > +			if (secno >= MAIN_SECS(sbi)) {
> > +				f2fs_stop_checkpoint(sbi, false,
> > +						STOP_CP_REASON_OUTOF_RAGNE);
> > +				f2fs_bug_on(sbi, 1);
> > +			}
> >   		} else {
> >   			go_left = 1;
> >   			left_start = hint - 1;
> > @@ -2682,7 +2686,11 @@ static void get_new_segment(struct f2fs_sb_info *sbi,
> >   		}
> >   		left_start = find_first_zero_bit(free_i->free_secmap,
> >   							MAIN_SECS(sbi));
> > -		f2fs_bug_on(sbi, left_start >= MAIN_SECS(sbi));
> > +		if (left_start >= MAIN_SECS(sbi)) {
> > +			f2fs_stop_checkpoint(sbi, false,
> > +					STOP_CP_REASON_OUTOF_RAGNE);
> > +			f2fs_bug_on(sbi, 1);
> > +		}
> >   		break;
> >   	}
> >   	secno = left_start;
> > diff --git a/include/linux/f2fs_fs.h b/include/linux/f2fs_fs.h
> > index 053137a0..72c6782 100644
> > --- a/include/linux/f2fs_fs.h
> > +++ b/include/linux/f2fs_fs.h
> > @@ -81,6 +81,7 @@ enum stop_cp_reason {
> >   	STOP_CP_REASON_CORRUPTED_SUMMARY,
> >   	STOP_CP_REASON_UPDATE_INODE,
> >   	STOP_CP_REASON_FLUSH_FAIL,
> > +	STOP_CP_REASON_OUTOF_RAGNE,
> >   	STOP_CP_REASON_MAX,
> >   };
> >   
> > --
> > 1.9.1