Re: [PATCH v5 09/10] xfs: Allow block allocator to take an alignment hint

[Christoph Hellwig]

>  	else if (ap->datatype & XFS_ALLOC_USERDATA)
>  		align = xfs_get_extsz_hint(ap->ip);
> +
> +	if (align > 1 && (ap->flags & XFS_BMAPI_EXTSZALIGN))
> +		args->alignment = align;
> +

Add a comment please.

> +/* Try to align allocations to the extent size hint */
> +#define XFS_BMAPI_EXTSZALIGN	(1u << 11)

Shouldn't we be doing this by default for any extent size hint
based allocations?

>  	bool			found;
>  	bool			atomic_sw = flags & XFS_REFLINK_ATOMIC_SW;
> +	uint32_t		bmapi_flags = XFS_BMAPI_COWFORK |
> +					      XFS_BMAPI_PREALLOC;
> +
> +	if (atomic_sw)
> +		bmapi_flags |= XFS_BMAPI_EXTSZALIGN;

Please add a comment why you are doing this.