>-----Original Message-----
>From: Jaegeuk Kim [mailto:[email protected]]
>Sent: Friday, December 15, 2017 12:21 PM
>To: heyunlei
>Cc: Yuchao (T); [email protected]; Wangbintian; Jianing 
>(Euler)
>Subject: Re: [f2fs-dev][PATCH RFC] f2fs: fix an error case of missing update 
>inode page
>
>On 12/15, heyunlei wrote:
>>
>>
>> >-----Original Message-----
>> >From: Jaegeuk Kim [mailto:[email protected]]
>> >Sent: Friday, December 15, 2017 3:46 AM
>> >To: heyunlei
>> >Cc: Yuchao (T); [email protected]; Wangbintian; 
>> >Jianing (Euler)
>> >Subject: Re: [f2fs-dev][PATCH RFC] f2fs: fix an error case of missing 
>> >update inode page
>> >
>> >On 12/05, Yunlei He wrote:
>> >> -Thread A                                 Thread B
>> >>
>> >> -write_checkpoint
>> >>   -block_operations
>> >>           -f2fs_unlock_all                -f2fs_sync_file
>> >>                                                   -f2fs_write_inode
>> >>                                                           
>> >> -f2fs_inode_synced
>> >>
>> >>                   -f2fs_sync_inode_meta
>> >>                           -sync_node_pages
>> >>                                                                   
>> >> -set_page_drity
>> >>
>> >> In this case, if sudden power off without next new checkpoint,
>> >> the last inode page update will lost. wb_writeback is same with
>> >> fsync.
>> >
>> >Does this patch fix the problem?
>> >
>> I modify code as below:
>> @@ -366,7 +366,7 @@ int update_inode(struct inode *inode, struct page 
>> *node_page)
>>         struct extent_tree *et = F2FS_I(inode)->extent_tree;
>>
>>         f2fs_inode_synced(inode);
>> -
>> +       msleep(10000);
>>         f2fs_wait_on_page_writeback(node_page, NODE, true);
>>
>> shell 1:                                       shell2:
>> dd if=/dev/zero of=./test bs=1M count=10
>> sync
>> echo "hello" >> ./test
>> fsync test  // sleep 10s
>>                                               sync  //return quickly
>>                                                                              
>>          echo c > /proc/sysrq-trigger  //before fsync return
>> fsck will find iblocks mismatch, and with this patch it 's ok.
>
>So, do you mean it was fixed by adding msleep() on top of this patch as well?
>Like:
>       - f2fs_write_inode()
>               - set_page_drity
>               - f2fs_inode_synced
>               - msleep(10000);
>
Yes,  write_checkpoint will be blocked in sync dirty node pages, until fsync 
update inode
page and unlock node page.

Thanks.
>>
>> Besides,I came across another error like this:
>>
>> f2fs_inode-> i_xattr_nid is non-zero, but node blkaddr in raw nat entry is 
>> NULL.
>>
>> This case makes sense to this problem also.
>>
>> > -write_checkpoint
>> >    -block_operations
>> >            -f2fs_unlock_all                -f2fs_sync_file
>> >                                                    -f2fs_write_inode
>> >                                                            -set_page_drity
>> >                                                            
>> > -f2fs_inode_synced
>> >                    -f2fs_sync_inode_meta
>> >                            -sync_node_pages
>> >
>> >I think, we need to cover f2fs_lock_op() for f2fs_write_inode() again.
>>
>> It can also work well with f2fs_lock_op(), I am afraid other cases will 
>> update inode
>> like f2fs_write_inode without f2fs_lock_op
>>
>> Thanks
>> >
>> >Thanks,
>> >
>> >>
>> >> Signed-off-by: Yunlei He <[email protected]>
>> >> ---
>> >>  fs/f2fs/f2fs.h  |  4 ++--
>> >>  fs/f2fs/inode.c | 15 +++++++--------
>> >>  2 files changed, 9 insertions(+), 10 deletions(-)
>> >>
>> >> diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
>> >> index 82f1dc3..38f9324 100644
>> >> --- a/fs/f2fs/f2fs.h
>> >> +++ b/fs/f2fs/f2fs.h
>> >> @@ -2513,8 +2513,8 @@ int f2fs_getattr(const struct path *path, struct 
>> >> kstat *stat,
>> >>  struct inode *f2fs_iget(struct super_block *sb, unsigned long ino);
>> >>  struct inode *f2fs_iget_retry(struct super_block *sb, unsigned long ino);
>> >>  int try_to_free_nats(struct f2fs_sb_info *sbi, int nr_shrink);
>> >> -int update_inode(struct inode *inode, struct page *node_page);
>> >> -int update_inode_page(struct inode *inode);
>> >> +void update_inode(struct inode *inode, struct page *node_page);
>> >> +void update_inode_page(struct inode *inode);
>> >>  int f2fs_write_inode(struct inode *inode, struct writeback_control *wbc);
>> >>  void f2fs_evict_inode(struct inode *inode);
>> >>  void handle_failed_inode(struct inode *inode);
>> >> diff --git a/fs/f2fs/inode.c b/fs/f2fs/inode.c
>> >> index b4c4f2b..10d3c7c 100644
>> >> --- a/fs/f2fs/inode.c
>> >> +++ b/fs/f2fs/inode.c
>> >> @@ -360,14 +360,15 @@ struct inode *f2fs_iget_retry(struct super_block 
>> >> *sb, unsigned long ino)
>> >>   return inode;
>> >>  }
>> >>
>> >> -int update_inode(struct inode *inode, struct page *node_page)
>> >> +void update_inode(struct inode *inode, struct page *node_page)
>> >>  {
>> >>   struct f2fs_inode *ri;
>> >>   struct extent_tree *et = F2FS_I(inode)->extent_tree;
>> >>
>> >> - f2fs_inode_synced(inode);
>> >> -
>> >>   f2fs_wait_on_page_writeback(node_page, NODE, true);
>> >> + set_page_dirty(node_page);
>> >> +
>> >> + f2fs_inode_synced(inode);
>> >>
>> >>   ri = F2FS_INODE(node_page);
>> >>
>> >> @@ -426,10 +427,9 @@ int update_inode(struct inode *inode, struct page 
>> >> *node_page)
>> >>   if (inode->i_nlink == 0)
>> >>           clear_inline_node(node_page);
>> >>
>> >> - return set_page_dirty(node_page);
>> >>  }
>> >>
>> >> -int update_inode_page(struct inode *inode)
>> >> +void update_inode_page(struct inode *inode)
>> >>  {
>> >>   struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
>> >>   struct page *node_page;
>> >> @@ -444,11 +444,10 @@ int update_inode_page(struct inode *inode)
>> >>           } else if (err != -ENOENT) {
>> >>                   f2fs_stop_checkpoint(sbi, false);
>> >>           }
>> >> -         return 0;
>> >> +         return;
>> >>   }
>> >> - ret = update_inode(inode, node_page);
>> >> + update_inode(inode, node_page);
>> >>   f2fs_put_page(node_page, 1);
>> >> - return ret;
>> >>  }
>> >>
>> >>  int f2fs_write_inode(struct inode *inode, struct writeback_control *wbc)
>> >> --
>> >> 1.9.1

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