Re: [PATCH v3 1/2] ocfs2: Add ocfs2_emergency_state helper and apply to setattr

[Joseph Qi <joseph.qi@linux.alibaba.com>]

On 2025/12/2 10:54, Ahmet Eray Karadag wrote:
> To centralize error checking, follow the pattern of other filesystems
> like ext4 (which uses `ext4_emergency_state()`), and prepare for
> future enhancements, this patch introduces a new helper function:
> `ocfs2_emergency_state()`.
> 
> The purpose of this helper is to provide a single, unified location
> for checking all filesystem-level emergency conditions. In this
> initial implementation, the function only checks for the existing
> hard and soft read-only modes, returning -EROFS if either is set.
> 
> This provides a foundation where future checks (e.g., for fatal error
> states returning -EIO, or shutdown states) can be easily added in
> one place.
> 
> This patch also adds this new check to the beginning of
> `ocfs2_setattr()`. This ensures that operations like `ftruncate`
> (which triggered the original BUG) fail-fast with -EROFS when the
> filesystem is already in a read-only state.
> 
> Suggested-by: Heming Zhao <heming.zhao@suse.com>
> Co-developed-by: Albin Babu Varghese <albinbabuvarghese20@gmail.com>
> Signed-off-by: Albin Babu Varghese <albinbabuvarghese20@gmail.com>
> Signed-off-by: Ahmet Eray Karadag <eraykrdg1@gmail.com>
> ---
> v2:
>  - Introducing new function `ocfs2_is_readonly` to lower the cost
>  - Using unlikely for status check
> ---
> v3:
>  - Fix compilation error (missing semicolon).
> ---
>  fs/ocfs2/file.c  |  6 ++++++
>  fs/ocfs2/ocfs2.h | 18 ++++++++++++++++++
>  2 files changed, 24 insertions(+)
> 
> diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
> index 21d797ccccd0..253b4f300127 100644
> --- a/fs/ocfs2/file.c
> +++ b/fs/ocfs2/file.c
> @@ -1137,6 +1137,12 @@ int ocfs2_setattr(struct mnt_idmap *idmap, struct dentry *dentry,
>  					from_kgid(&init_user_ns, attr->ia_gid) : 0);
>  
>  	/* ensuring we don't even attempt to truncate a symlink */

The above comments is for "if (S_ISLNK(inode->i_mode))".
So it should be move down just before symlink check.

> +	status = ocfs2_emergency_state(osb);
> +	if (unlikely(status)) {
> +		mlog_errno(status);
> +		goto bail;
> +	}
> +
>  	if (S_ISLNK(inode->i_mode))
>  		attr->ia_valid &= ~ATTR_SIZE;
>  
> diff --git a/fs/ocfs2/ocfs2.h b/fs/ocfs2/ocfs2.h
> index 6aaa94c554c1..91a861babf74 100644
> --- a/fs/ocfs2/ocfs2.h
> +++ b/fs/ocfs2/ocfs2.h
> @@ -680,6 +680,24 @@ static inline int ocfs2_is_soft_readonly(struct ocfs2_super *osb)
>  	return ret;
>  }
>  
> +static inline int ocfs2_is_readonly(struct ocfs2_super *osb)
> +{
> +	int ret;
> +	spin_lock(&osb->osb_lock);
> +	ret = osb->osb_flags & (OCFS2_OSB_SOFT_RO | OCFS2_OSB_HARD_RO);
> +	spin_unlock(&osb->osb_lock);
> +
> +	return ret;
> +}
> +
> +static inline int ocfs2_emergency_state(struct ocfs2_super *osb)
> +{
> +	if (ocfs2_is_readonly(osb)) {

The '{' can be eliminated.

Joseph

> +		return -EROFS;
> +	}
> +	return 0;
> +}
> +
>  static inline int ocfs2_clusterinfo_valid(struct ocfs2_super *osb)
>  {
>  	return (osb->s_feature_incompat &