On Dec 02, 2019 / 10:38, Shin'ichiro Kawasaki wrote: > On Nov 30, 2019 / 15:49, Chao Yu wrote: > > On 2019/11/29 13:21, Shinichiro Kawasaki wrote: > > > On Nov 28, 2019 / 20:39, Chao Yu wrote: > > >> On 2019/11/28 13:31, Shinichiro Kawasaki wrote: > > >>> On Nov 25, 2019 / 15:37, Chao Yu wrote: > > >>>> On 2019/11/14 16:19, Shin'ichiro Kawasaki wrote: > > >>>>> To catch f2fs bugs in write pointer handling code for zoned block > > >>>>> devices, check write pointers of non-open zones that current segments > > >>>>> do > > >>>>> not point to. Do this check at mount time, after the fsync data > > >>>>> recovery > > >>>>> and current segments' write pointer consistency fix. Or when fsync > > >>>>> data > > >>>>> recovery is disabled by mount option, do the check when there is no > > >>>>> fsync > > >>>>> data. > > >>>>> > > >>>>> Check two items comparing write pointers with valid block maps in SIT. > > >>>>> The first item is check for zones with no valid blocks. When there is > > >>>>> no > > >>>>> valid blocks in a zone, the write pointer should be at the start of > > >>>>> the > > >>>>> zone. If not, next write operation to the zone will cause unaligned > > >>>>> write > > >>>>> error. If write pointer is not at the zone start, make mount fail and > > >>>>> ask > > >>>>> users to run fsck. > > >>>>> > > >>>>> The second item is check between the write pointer position and the > > >>>>> last > > >>>>> valid block in the zone. It is unexpected that the last valid block > > >>>>> position is beyond the write pointer. In such a case, report as a bug. > > >>>>> Fix is not required for such zone, because the zone is not selected > > >>>>> for > > >>>>> next write operation until the zone get discarded. > > >>>>> > > >>>>> Also move a constant F2FS_REPORT_ZONE from super.c to f2fs.h to use it > > >>>>> in segment.c also. > > >>>>> > > >>>>> Signed-off-by: Shin'ichiro Kawasaki <[email protected]> > > >>>>> --- > > >>>>> fs/f2fs/f2fs.h | 3 + > > >>>>> fs/f2fs/segment.c | 149 > > >>>>> ++++++++++++++++++++++++++++++++++++++++++++++ > > >>>>> fs/f2fs/super.c | 16 ++++- > > >>>>> 3 files changed, 165 insertions(+), 3 deletions(-) > > >>>>> > > >>>>> diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h > > >>>>> index a2e24718c13b..1bb64950d793 100644 > > >>>>> --- a/fs/f2fs/f2fs.h > > >>>>> +++ b/fs/f2fs/f2fs.h > > >>>>> @@ -3137,6 +3137,7 @@ int f2fs_lookup_journal_in_cursum(struct > > >>>>> f2fs_journal *journal, int type, > > >>>>> unsigned int val, int alloc); > > >>>>> void f2fs_flush_sit_entries(struct f2fs_sb_info *sbi, struct > > >>>>> cp_control *cpc); > > >>>>> int f2fs_fix_curseg_write_pointer(struct f2fs_sb_info *sbi); > > >>>>> +int f2fs_check_write_pointer(struct f2fs_sb_info *sbi); > > >>>>> int f2fs_build_segment_manager(struct f2fs_sb_info *sbi); > > >>>>> void f2fs_destroy_segment_manager(struct f2fs_sb_info *sbi); > > >>>>> int __init f2fs_create_segment_manager_caches(void); > > >>>>> @@ -3610,6 +3611,8 @@ static inline bool f2fs_blkz_is_seq(struct > > >>>>> f2fs_sb_info *sbi, int devi, > > >>>>> > > >>>>> return test_bit(zno, FDEV(devi).blkz_seq); > > >>>>> } > > >>>>> + > > >>>>> +#define F2FS_REPORT_NR_ZONES 4096 > > >>>>> #endif > > >>>>> > > >>>>> static inline bool f2fs_hw_should_discard(struct f2fs_sb_info *sbi) > > >>>>> diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c > > >>>>> index 6ece146dab34..29e3b6f62f8c 100644 > > >>>>> --- a/fs/f2fs/segment.c > > >>>>> +++ b/fs/f2fs/segment.c > > >>>>> @@ -4333,6 +4333,133 @@ static int sanity_check_curseg(struct > > >>>>> f2fs_sb_info *sbi) > > >>>>> > > >>>>> #ifdef CONFIG_BLK_DEV_ZONED > > >>>>> > > >>>>> +static int check_zone_write_pointer(struct f2fs_sb_info *sbi, > > >>>>> + struct f2fs_dev_info *fdev, > > >>>>> + struct blk_zone *zone) > > >>>>> +{ > > >>>>> + unsigned int wp_segno, wp_blkoff, zone_secno, zone_segno, segno; > > >>>>> + block_t zone_block, wp_block, last_valid_block; > > >>>>> + unsigned int log_sectors_per_block = sbi->log_blocksize - > > >>>>> SECTOR_SHIFT; > > >>>>> + int i, s, b; > > >>>>> + struct seg_entry *se; > > >>>>> + > > >>>>> + wp_block = fdev->start_blk + (zone->wp >> > > >>>>> log_sectors_per_block); > > >>>>> + wp_segno = GET_SEGNO(sbi, wp_block); > > >>>>> + wp_blkoff = wp_block - START_BLOCK(sbi, wp_segno); > > >>>>> + zone_block = fdev->start_blk + (zone->start >> > > >>>>> log_sectors_per_block); > > >>>>> + zone_segno = GET_SEGNO(sbi, zone_block); > > >>>>> + zone_secno = GET_SEC_FROM_SEG(sbi, zone_segno); > > >>>>> + > > >>>>> + if (zone_segno >= MAIN_SEGS(sbi)) > > >>>>> + return 0; > > >>>>> + > > >>>>> + /* > > >>>>> + * Skip check of zones cursegs point to, since > > >>>>> + * fix_curseg_write_pointer() checks them. > > >>>>> + */ > > >>>>> + for (i = 0; i < NO_CHECK_TYPE; i++) > > >>>>> + if (zone_secno == GET_SEC_FROM_SEG(sbi, > > >>>>> + CURSEG_I(sbi, > > >>>>> i)->segno)) > > >>>>> + return 0; > > >>>>> + > > >>>>> + /* > > >>>>> + * Get last valid block of the zone. > > >>>>> + */ > > >>>>> + last_valid_block = zone_block - 1; > > >>>>> + for (s = sbi->segs_per_sec - 1; s >= 0; s--) { > > >>>>> + segno = zone_segno + s; > > >>>>> + se = get_seg_entry(sbi, segno); > > >>>>> + for (b = sbi->blocks_per_seg - 1; b >= 0; b--) > > >>>>> + if (f2fs_test_bit(b, se->cur_valid_map)) { > > >>>>> + last_valid_block = START_BLOCK(sbi, > > >>>>> segno) + b; > > >>>>> + break; > > >>>>> + } > > >>>>> + if (last_valid_block >= zone_block) > > >>>>> + break; > > >>>>> + } > > >>>>> + > > >>>>> + /* > > >>>>> + * If last valid block is beyond the write pointer, report the > > >>>>> + * inconsistency. This inconsistency does not cause write error > > >>>>> + * because the zone will not be selected for write operation > > >>>>> until > > >>>>> + * it get discarded. Just report it. > > >>>>> + */ > > >>>>> + if (last_valid_block >= wp_block) { > > >>>>> + f2fs_notice(sbi, "Valid block beyond write pointer: " > > >>>>> + "valid block[0x%x,0x%x] wp[0x%x,0x%x]", > > >>>>> + GET_SEGNO(sbi, last_valid_block), > > >>>>> + GET_BLKOFF_FROM_SEG0(sbi, last_valid_block), > > >>>>> + wp_segno, wp_blkoff); > > >>>>> + return 0; > > >>>>> + } > > >>>>> + > > >>>>> + /* > > >>>>> + * If there is no valid block in the zone and if write pointer > > >>>>> is > > >>>>> + * not at zone start, report the error to run fsck. > > >>>> > > >>>> So we only need to report this as inconsistent status in the condition > > >>>> of > > >>>> discard has been triggered, right? otherwise, f2fs will trigger > > >>>> discard later > > >>>> to reset zone->wp before opening this zone? > > >>> > > >>> Hmm, my intent was to catch the inconsistency at mount time, assuming > > >>> the > > >>> inconsistency is not expected at mount time. In other words, I assume > > >>> that > > >>> discard is triggered for zones without valid blocks before that last > > >>> clean > > >> > > >> IIUC, if there is too many pending discards, put_super() may drop > > >> discard entries > > >> to avoid delaying umount, so we can not assume all discards are always > > >> being > > >> triggered. > > > > > > I see. In this case, current code in the patch will miss-detect the zone > > > with > > > the dropped discard entries. This is not good. Thank you for catching > > > this :) > > > > > >> > > >> So what I mean is for the condition of a) there is valid (including > > >> fsycned) block, > > >> b) zone->wp is not at correct position, f2fs can handle it by issuing > > >> discard. Let > > >> me know if I misread this comment. > > > > > > For the condition a), do you mean "there is _no_ valid (include fsynced) > > > block"? > > > > Oops, yes, I meant that. :) > > OK, will add the discard by reset zone and will post next version. Thanks. > > Also, I noticed that this patch series have conflicts with the latest linux > kernel master branch because of the commit d41003513e61 "block: rework zone > reporting", which changed interface of blkdev_report_zones() function. > Will rebase to the master branch and resolve the conflicts.
I have sent out the v4 series. As always, review will be appreciated. I noticed that the conditions a) and b) can be applied to a check logic in the 1st patch also. It checks that the newly assigned zones to cursegs have write pointers at zone start. If not, the v3 patch reports an error for fsck run. I replaced the error report with discard by reset zone in same manner as the 2nd patch. With this change, no longer need to ask fsck run. A little bit simpler. -- Best Regards, Shin'ichiro Kawasaki _______________________________________________ Linux-f2fs-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel
