Re: [f2fs-dev] [PATCH v3 2/2] fsck.f2fs: Check write pointer consistency with current segments
On Aug 29, 2019 / 22:49, Chao Yu wrote:
> On 2019-8-29 14:35, Shin'ichiro Kawasaki wrote:
> > On sudden f2fs shutdown, zoned block device status and f2fs current
> > segment positions in meta data can be inconsistent. When f2fs shutdown
> > happens before write operations completes, write pointers of zoned block
> > devices can go further but f2fs meta data keeps current segments at
> > positions before the write operations. After remounting the f2fs, the
> > inconsistency causes write operations not at write pointers and
> > "Unaligned write command" error is reported. This error was observed when
> > xfstests test case generic/388 was run with f2fs on a zoned block device.
> >
> > To avoid the error, have f2fs.fsck check consistency between each current
> > segment's position and the write pointer of the zone the current segment
> > points to. If the write pointer goes advance from the current segment,
> > fix the current segment position setting at same as the write pointer
> > position. In case the write pointer is behind the current segment, write
> > zero data at the write pointer position to make write pointer position at
> > same as the current segment.
> >
> > When inconsistencies are found, turn on c.bug_on flag in fsck_verify() to
> > ask users to fix them or not. When inconsistencies get fixed, turn on
> > 'force' flag in fsck_verify() to enforce fixes in following checks. This
> > position fix is done at the beginning of do_fsck() function so that other
> > checks reflect the current segment modification.
> >
> > Signed-off-by: Shin'ichiro Kawasaki
> > Reviewed-by: Chao Yu
> > ---
> > fsck/fsck.c | 131
> > fsck/fsck.h | 3 ++
> > fsck/main.c | 2 +
> > 3 files changed, 136 insertions(+)
> >
> > diff --git a/fsck/fsck.c b/fsck/fsck.c
> > index 8953ca1..f45ca39 100644
> > --- a/fsck/fsck.c
> > +++ b/fsck/fsck.c
> > @@ -2574,6 +2574,123 @@ out:
> > return cnt;
> > }
> >
> > +struct write_pointer_check_data {
> > + struct f2fs_sb_info *sbi;
> > + struct device_info *dev;
> > +};
> > +
> > +static int fsck_chk_write_pointer(int i, struct blk_zone *blkz, void
> > *opaque)
> > +{
> > + struct write_pointer_check_data *wpd = opaque;
> > + struct f2fs_sb_info *sbi = wpd->sbi;
> > + struct device_info *dev = wpd->dev;
> > + struct f2fs_fsck *fsck = F2FS_FSCK(sbi);
> > + block_t zone_block, wp_block, wp_blkoff, cs_block, b;
> > + unsigned int zone_segno, wp_segno;
> > + struct seg_entry *se;
> > + struct curseg_info *cs;
> > + int cs_index, ret;
> > + int log_sectors_per_block = sbi->log_blocksize - SECTOR_SHIFT;
> > + unsigned int segs_per_zone = sbi->segs_per_sec * sbi->secs_per_zone;
> > + void *zero_blk;
> > +
> > + if (blk_zone_conv(blkz))
> > + return 0;
> > +
> > + zone_block = dev->start_blkaddr
> > + + (blk_zone_sector(blkz) >> log_sectors_per_block);
> > + zone_segno = GET_SEGNO(sbi, zone_block);
> > + wp_block = dev->start_blkaddr
> > + + (blk_zone_wp_sector(blkz) >> log_sectors_per_block);
> > + wp_segno = GET_SEGNO(sbi, wp_block);
> > + wp_blkoff = wp_block - START_BLOCK(sbi, wp_segno);
> > +
> > + /* find the curseg which points to the zone */
> > + for (cs_index = 0; cs_index < NO_CHECK_TYPE; cs_index++) {
> > + cs = _I(sbi)->curseg_array[cs_index];
> > + if (zone_segno <= cs->segno &&
> > + cs->segno < zone_segno + segs_per_zone)
> > + break;
> > + }
> > +
> > + if (cs_index >= NR_CURSEG_TYPE)
> > + return 0;
> > +
> > + /* check write pointer consistency with the curseg in the zone */
> > + cs_block = START_BLOCK(sbi, cs->segno) + cs->next_blkoff;
> > + if (wp_block == cs_block)
> > + return 0;
> > +
> > + if (!c.fix_on) {
> > + MSG(0, "Inconsistent write pointer: "
> > + "curseg %d[0x%x,0x%x] wp[0x%x,0x%x]\n",
> > + cs_index, cs->segno, cs->next_blkoff, wp_segno, wp_blkoff);
> > + fsck->chk.wp_inconsistent_zones++;
> > + return 0;
> > + }
> > +
> > + /*
> > +* If the curseg is in advance from the write pointer, write zero to
> > +* move the write pointer forward to the same position as the curseg.
> > +*/
> > + if (wp_block < cs_block) {
> > + ret = 0;
> > + zero_blk = calloc(BLOCK_SZ, 1);
> > + if (!zero_blk)
> > + return -EINVAL;
> > +
> > + FIX_MSG("Advance write pointer to match with curseg %d: "
> > + "[0x%x,0x%x]->[0x%x,0x%x]",
> > + cs_index, wp_segno, wp_blkoff,
> > + cs->segno, cs->next_blkoff);
> > + for (b = wp_block; b < cs_block && !ret; b++)
> > + ret = dev_write_block(zero_blk, b);
> > +
> > + fsck->chk.wp_fixed_zones++;
> > + free(zero_blk);
> > + return ret;
> > + }
> > +
> > + /*
> > +* If
Re: [f2fs-dev] [PATCH v3 2/2] fsck.f2fs: Check write pointer consistency with current segments
On 2019-8-29 14:35, Shin'ichiro Kawasaki wrote:
> On sudden f2fs shutdown, zoned block device status and f2fs current
> segment positions in meta data can be inconsistent. When f2fs shutdown
> happens before write operations completes, write pointers of zoned block
> devices can go further but f2fs meta data keeps current segments at
> positions before the write operations. After remounting the f2fs, the
> inconsistency causes write operations not at write pointers and
> "Unaligned write command" error is reported. This error was observed when
> xfstests test case generic/388 was run with f2fs on a zoned block device.
>
> To avoid the error, have f2fs.fsck check consistency between each current
> segment's position and the write pointer of the zone the current segment
> points to. If the write pointer goes advance from the current segment,
> fix the current segment position setting at same as the write pointer
> position. In case the write pointer is behind the current segment, write
> zero data at the write pointer position to make write pointer position at
> same as the current segment.
>
> When inconsistencies are found, turn on c.bug_on flag in fsck_verify() to
> ask users to fix them or not. When inconsistencies get fixed, turn on
> 'force' flag in fsck_verify() to enforce fixes in following checks. This
> position fix is done at the beginning of do_fsck() function so that other
> checks reflect the current segment modification.
>
> Signed-off-by: Shin'ichiro Kawasaki
> Reviewed-by: Chao Yu
> ---
> fsck/fsck.c | 131
> fsck/fsck.h | 3 ++
> fsck/main.c | 2 +
> 3 files changed, 136 insertions(+)
>
> diff --git a/fsck/fsck.c b/fsck/fsck.c
> index 8953ca1..f45ca39 100644
> --- a/fsck/fsck.c
> +++ b/fsck/fsck.c
> @@ -2574,6 +2574,123 @@ out:
> return cnt;
> }
>
> +struct write_pointer_check_data {
> + struct f2fs_sb_info *sbi;
> + struct device_info *dev;
> +};
> +
> +static int fsck_chk_write_pointer(int i, struct blk_zone *blkz, void *opaque)
> +{
> + struct write_pointer_check_data *wpd = opaque;
> + struct f2fs_sb_info *sbi = wpd->sbi;
> + struct device_info *dev = wpd->dev;
> + struct f2fs_fsck *fsck = F2FS_FSCK(sbi);
> + block_t zone_block, wp_block, wp_blkoff, cs_block, b;
> + unsigned int zone_segno, wp_segno;
> + struct seg_entry *se;
> + struct curseg_info *cs;
> + int cs_index, ret;
> + int log_sectors_per_block = sbi->log_blocksize - SECTOR_SHIFT;
> + unsigned int segs_per_zone = sbi->segs_per_sec * sbi->secs_per_zone;
> + void *zero_blk;
> +
> + if (blk_zone_conv(blkz))
> + return 0;
> +
> + zone_block = dev->start_blkaddr
> + + (blk_zone_sector(blkz) >> log_sectors_per_block);
> + zone_segno = GET_SEGNO(sbi, zone_block);
> + wp_block = dev->start_blkaddr
> + + (blk_zone_wp_sector(blkz) >> log_sectors_per_block);
> + wp_segno = GET_SEGNO(sbi, wp_block);
> + wp_blkoff = wp_block - START_BLOCK(sbi, wp_segno);
> +
> + /* find the curseg which points to the zone */
> + for (cs_index = 0; cs_index < NO_CHECK_TYPE; cs_index++) {
> + cs = _I(sbi)->curseg_array[cs_index];
> + if (zone_segno <= cs->segno &&
> + cs->segno < zone_segno + segs_per_zone)
> + break;
> + }
> +
> + if (cs_index >= NR_CURSEG_TYPE)
> + return 0;
> +
> + /* check write pointer consistency with the curseg in the zone */
> + cs_block = START_BLOCK(sbi, cs->segno) + cs->next_blkoff;
> + if (wp_block == cs_block)
> + return 0;
> +
> + if (!c.fix_on) {
> + MSG(0, "Inconsistent write pointer: "
> + "curseg %d[0x%x,0x%x] wp[0x%x,0x%x]\n",
> + cs_index, cs->segno, cs->next_blkoff, wp_segno, wp_blkoff);
> + fsck->chk.wp_inconsistent_zones++;
> + return 0;
> + }
> +
> + /*
> + * If the curseg is in advance from the write pointer, write zero to
> + * move the write pointer forward to the same position as the curseg.
> + */
> + if (wp_block < cs_block) {
> + ret = 0;
> + zero_blk = calloc(BLOCK_SZ, 1);
> + if (!zero_blk)
> + return -EINVAL;
> +
> + FIX_MSG("Advance write pointer to match with curseg %d: "
> + "[0x%x,0x%x]->[0x%x,0x%x]",
> + cs_index, wp_segno, wp_blkoff,
> + cs->segno, cs->next_blkoff);
> + for (b = wp_block; b < cs_block && !ret; b++)
> + ret = dev_write_block(zero_blk, b);
> +
> + fsck->chk.wp_fixed_zones++;
> + free(zero_blk);
> + return ret;
> + }
> +
> + /*
> + * If the write pointer is in advance from the curseg, modify the
> + * curseg position to be same as the write pointer.
> + */
> +
