Messages in this thread | | | Subject | Re: [f2fs-dev] [PATCH] f2fs: reset free segment to prefree status when do_checkpoint() fail | From | Chao Yu <> | Date | Thu, 29 Jul 2021 09:42:17 +0800 |
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Ping,
On 2021/7/20 8:04, Chao Yu wrote: > On 2021/7/20 2:25, Jaegeuk Kim wrote: >> On 07/19, Chao Yu wrote: >>> On 2021/4/27 20:37, Chao Yu wrote: >>>> I think just reverting dirty/free bitmap is not enough if checkpoint fails, >>>> due to we have updated sbi->cur_cp_pack and nat/sit bitmap, next CP tries >>>> to overwrite last valid meta/node/data, then filesystem will be corrupted. >>>> >>>> So I suggest to set cp_error if do_checkpoint() fails until we can handle >>>> all cases, which is not so easy. >>>> >>>> How do you think? >>> >>> Let's add below patch first before you figure out the patch which covers all >>> things. >>> >>> From 3af957c98e9e04259f8bb93ca0b74ba164f3f27e Mon Sep 17 00:00:00 2001 >>> From: Chao Yu <chao@kernel.org> >>> Date: Mon, 19 Jul 2021 16:37:44 +0800 >>> Subject: [PATCH] f2fs: fix to stop filesystem update once CP failed >>> >>> During f2fs_write_checkpoint(), once we failed in >>> f2fs_flush_nat_entries() or do_checkpoint(), metadata of filesystem >>> such as prefree bitmap, nat/sit version bitmap won't be recovered, >>> it may cause f2fs image to be inconsistent, let's just set CP error >>> flag to avoid further updates until we figure out a scheme to rollback >>> all metadatas in such condition. >>> >>> Reported-by: Yangtao Li <frank.li@vivo.com> >>> Signed-off-by: Yangtao Li <frank.li@vivo.com> >>> Signed-off-by: Chao Yu <chao@kernel.org> >>> --- >>> fs/f2fs/checkpoint.c | 10 +++++++--- >>> 1 file changed, 7 insertions(+), 3 deletions(-) >>> >>> diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c >>> index 6c208108d69c..096c85022f62 100644 >>> --- a/fs/f2fs/checkpoint.c >>> +++ b/fs/f2fs/checkpoint.c >>> @@ -1639,8 +1639,10 @@ int f2fs_write_checkpoint(struct f2fs_sb_info *sbi, struct cp_control *cpc) >>> >>> /* write cached NAT/SIT entries to NAT/SIT area */ >>> err = f2fs_flush_nat_entries(sbi, cpc); >>> - if (err) >>> + if (err) { >>> + f2fs_stop_checkpoint(sbi, false); >> >> I think we should abuse this, since we can get any known ENOMEM as well. > > Yup, but one critical issue here is it can break A/B update of NAT area, > so, in order to fix this hole, how about using NOFAIL memory allocation > in f2fs_flush_nat_entries() first until we figure out the finial scheme? > > Thanks, > >> >>> goto stop; >>> + } >>> >>> f2fs_flush_sit_entries(sbi, cpc); >>> >>> @@ -1648,10 +1650,12 @@ int f2fs_write_checkpoint(struct f2fs_sb_info *sbi, struct cp_control *cpc) >>> f2fs_save_inmem_curseg(sbi); >>> >>> err = do_checkpoint(sbi, cpc); >>> - if (err) >>> + if (err) { >>> + f2fs_stop_checkpoint(sbi, false); >>> f2fs_release_discard_addrs(sbi); >>> - else >>> + } else { >>> f2fs_clear_prefree_segments(sbi, cpc); >>> + } >>> >>> f2fs_restore_inmem_curseg(sbi); >>> stop: >>> -- >>> 2.22.1 > > > _______________________________________________ > Linux-f2fs-devel mailing list > Linux-f2fs-devel@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel >
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