Hi Jaegeuk,
On 2016/11/17 3:13, Jaegeuk Kim wrote:
> Hi Chao,
>
> On Wed, Nov 16, 2016 at 08:12:11PM +0800, Chao Yu wrote:
>> For below two cases, we can't guarantee data consistence:
>>
>> a)
>> 1. xfs_io "pwrite 0 4195328" "fsync"
>> 2. xfs_io "pwrite 4195328 1024" "fdatasync"
>> 3. godown
>> 4. umount & mount
>> --> isize we updated before fdatasync won't be recovered
>>
>> b)
>> 1. xfs_io "pwrite -S 0xcc 0 4202496" "fsync"
>> 2. xfs_io "fpunch 4194304 4096" "fdatasync"
>> 3. godown
>> 4. umount & mount
>> --> dnode we punched before fdatasync won't be recovered
>>
>> The reason is that normally fdatasync won't be aware of modification
>> of metadata in file, e.g. isize changing, dnode updating, so in ->fsync
>> we will skip flushing node pages for above cases, result in making
>> fdatasynced file being lost during recovery.
>>
>> Introduce FDATASYNC_INO global ino cache for tracking node changing,
>> later fdatasync choose to flush nodes depend on ino cache state.
>
> We don't need to add this additionally, and would be better to consider other
> major metadata as well.
>
> How about this?
Seems it can't track file after evict?
Thanks,
>
> ---
> fs/f2fs/f2fs.h | 11 ++++++++++-
> fs/f2fs/file.c | 2 +-
> 2 files changed, 11 insertions(+), 2 deletions(-)
>
> diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
> index c9672a3..50ffa4f 100644
> --- a/fs/f2fs/f2fs.h
> +++ b/fs/f2fs/f2fs.h
> @@ -1727,8 +1727,17 @@ static inline void f2fs_i_size_write(struct inode
> *inode, loff_t i_size)
> set_inode_flag(inode, FI_AUTO_RECOVER);
> }
>
> -static inline bool f2fs_skip_inode_update(struct inode *inode)
> +static inline bool f2fs_skip_inode_update(struct inode *inode, int dsync)
> {
> + if (dsync) {
> + struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
> + bool ret;
> +
> + spin_lock(&sbi->inode_lock[DIRTY_META]);
> + ret = list_empty(&F2FS_I(inode)->gdirty_list);
> + spin_unlock(&sbi->inode_lock[DIRTY_META]);
> + return ret;
> + }
> if (!is_inode_flag_set(inode, FI_AUTO_RECOVER))
> return false;
> return F2FS_I(inode)->last_disk_size == i_size_read(inode);
> diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
> index d48c120..50123c6 100644
> --- a/fs/f2fs/file.c
> +++ b/fs/f2fs/file.c
> @@ -212,7 +212,7 @@ static int f2fs_do_sync_file(struct file *file, loff_t
> start, loff_t end,
> }
>
> /* if the inode is dirty, let's recover all the time */
> - if (!datasync && !f2fs_skip_inode_update(inode)) {
> + if (!f2fs_skip_inode_update(inode, datasync)) {
> f2fs_write_inode(inode, NULL);
> goto go_write;
> }
>
