On 12/10, Chao Yu wrote:
> Hi Jaegeuk,
>
> Let me try to understand this, in some cases, we can write a checkpoint pack
> which has wrong cp_ver, like in 1st cp pack which has even version number or
> 2nd
> cp pack which has odd version number, so if we load that kind of cp pack
> during
> fill_super, we may load wrong summary data from another older cp pack which cp
> version pointed to, is that right?
Yup. Especially we can use __start_cp_addr() when finding summary blocks. So, I
suspect it was able to cause missing summary blocks.
Thanks,
>
> Thanks,
>
> On 2016/11/25 10:32, Jaegeuk Kim wrote:
> > We don't guarantee cp_addr is fixed by cp_version.
> > This is to sync with f2fs-tools.
> >
> > Cc: sta...@vger.kernel.org
> > Signed-off-by: Jaegeuk Kim <jaeg...@kernel.org>
> > ---
> > fs/f2fs/checkpoint.c | 5 +++++
> > fs/f2fs/f2fs.h | 14 +++-----------
> > 2 files changed, 8 insertions(+), 11 deletions(-)
> >
> > diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c
> > index 54cc6a9..bf2f44c 100644
> > --- a/fs/f2fs/checkpoint.c
> > +++ b/fs/f2fs/checkpoint.c
> > @@ -789,6 +789,11 @@ int get_valid_checkpoint(struct f2fs_sb_info *sbi)
> > f2fs_put_page(cur_page, 1);
> > }
> > done:
> > + if (cur_page == cp1)
> > + sbi->cur_cp_pack = 1;
> > + else
> > + sbi->cur_cp_pack = 2;
> > +
> > f2fs_put_page(cp1, 1);
> > f2fs_put_page(cp2, 1);
> > return 0;
> > diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
> > index 62383d2..e22e7e1 100644
> > --- a/fs/f2fs/f2fs.h
> > +++ b/fs/f2fs/f2fs.h
> > @@ -792,6 +792,7 @@ struct f2fs_sb_info {
> >
> > /* for checkpoint */
> > struct f2fs_checkpoint *ckpt; /* raw checkpoint pointer */
> > + int cur_cp_pack; /* remain current cp pack */
> > spinlock_t cp_lock; /* for flag in ckpt */
> > struct inode *meta_inode; /* cache meta blocks */
> > struct mutex cp_mutex; /* checkpoint procedure lock */
> > @@ -1352,19 +1353,10 @@ static inline void *__bitmap_ptr(struct
> > f2fs_sb_info *sbi, int flag)
> >
> > static inline block_t __start_cp_addr(struct f2fs_sb_info *sbi)
> > {
> > - block_t start_addr;
> > - struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
> > - unsigned long long ckpt_version = cur_cp_version(ckpt);
> > -
> > - start_addr = le32_to_cpu(F2FS_RAW_SUPER(sbi)->cp_blkaddr);
> > + block_t start_addr = le32_to_cpu(F2FS_RAW_SUPER(sbi)->cp_blkaddr);
> >
> > - /*
> > - * odd numbered checkpoint should at cp segment 0
> > - * and even segment must be at cp segment 1
> > - */
> > - if (!(ckpt_version & 1))
> > + if (sbi->cur_cp_pack == 2)
> > start_addr += sbi->blocks_per_seg;
> > -
> > return start_addr;
> > }
> >
> >
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