Re: [PATCH 4/5] f2fs: remove nid_free from f2fs_new_inode

From: Jaegeuk Kim
Date: Sun Mar 17 2013 - 22:12:31 EST


2013-03-17 (ì), 17:27 +0900, Namjae Jeon:
> From: Namjae Jeon <namjae.jeon@xxxxxxxxxxx>
>
> we can remove nid_free from new inode allocation part.
> Since, nid_free is used to check if we need to free alloced nid
> in case of failure.
> Instead we can directly call alloc_nid_failed from that point, as
> there is no dependency in that path.
>
> Signed-off-by: Namjae Jeon <namjae.jeon@xxxxxxxxxxx>
> Signed-off-by: Amit Sahrawat <a.sahrawat@xxxxxxxxxxx>
> ---
> fs/f2fs/namei.c | 5 +----
> 1 file changed, 1 insertion(+), 4 deletions(-)
>
> diff --git a/fs/f2fs/namei.c b/fs/f2fs/namei.c
> index d4a171b..261d821 100644
> --- a/fs/f2fs/namei.c
> +++ b/fs/f2fs/namei.c
> @@ -24,7 +24,6 @@ static struct inode *f2fs_new_inode(struct inode *dir, umode_t mode)
> struct f2fs_sb_info *sbi = F2FS_SB(sb);
> nid_t ino;
> struct inode *inode;
> - bool nid_free = false;
> int err;
>
> inode = new_inode(sb);
> @@ -58,7 +57,7 @@ static struct inode *f2fs_new_inode(struct inode *dir, umode_t mode)
> err = insert_inode_locked(inode);
> if (err) {
> err = -EINVAL;
> - nid_free = true;
> + alloc_nid_failed(sbi, ino);
> goto out;
> }
>
> @@ -70,8 +69,6 @@ out:
> unlock_new_inode(inode);
> fail:
> iput(inode);
> - if (nid_free)
> - alloc_nid_failed(sbi, ino);

We should call alloc_nid_failed() after iput() is completed.
Otherwise, another f2fs_new_inode() is able to get this just-released
nid before iput(). In such a case, insert_inode_locked() can return
-EBUSY or iput() can free this newly allocated inode due to the i_lock
race.
Thanks,

> return ERR_PTR(err);
> }
>

--
Jaegeuk Kim
Samsung

Attachment: signature.asc
Description: This is a digitally signed message part