Re: [PATCH v2 2/5] ntfs: report attribute errors to fsnotify

[Hyunchul Lee <hyc.lee@gmail.com>]

Hi Baolin, 

>  folio_err_out:
> @@ -3720,7 +3737,8 @@ static int ntfs_attr_update_meta(struct attr_record *a, struct ntfs_inode *ni,
>  static int __ntfs_attr_update_mapping_pairs(struct ntfs_inode *ni,
>  					    s64 from_vcn,
>  					    struct ntfs_inode *locked_ni,
> -					    bool defer_attrlist)
> +					    bool defer_attrlist,
> +					    bool *error_reported)
>  {
>  	struct ntfs_attr_search_ctx *ctx;
>  	struct ntfs_inode *base_ni;
> @@ -4086,8 +4104,11 @@ static int __ntfs_attr_update_mapping_pairs(struct ntfs_inode *ni,
>  	return 0;
>  
>  put_err_out:
> -	if (ctx)
> +	if (ctx) {
> +		if (error_reported && ctx->error_reported)
> +			*error_reported = true;
>  		ntfs_attr_put_search_ctx(ctx);
> +	}
>  	return err;
>  }

__ntfs_attr_update_mapping_pairs() does:

  ntfs_attr_put_search_ctx(ctx);
  ctx = NULL

Therefore any later mapping or other errors can therefore lose report
state and duplicate reports. And The error_reported boolean only tell
us that some lower-level path has already emitted an error. Consequently
a report can incorrectly suppress a separate report for a later rollback
or resotre failure, even though that failure represents an independant
filesystem integrity problem.

Instead of carrying error_reported, would it be simpler to report each
error at its detection point and let fanofify merge repeated error
events? or would there be any alternatives?

-- 
Thanks,
Hyunchul