Re: [PATCH] xfs: reserve enough blocks to handle btree splits when remapping

[Christoph Hellwig <hch@infradead.org>]

> +static inline unsigned int
> +XFS_RMAPADD_SPACE_RES(
> +	struct xfs_mount	*mp)
> +{
> +	return xfs_sb_version_hasrmapbt(&mp->m_sb) ? mp->m_rmap_maxlevels : 0;
> +}

All the other helpers are macros.  While I much prefer inlines it might
be a good idea to do it in one go and also convert them to lower case
instead of screaming..

> +#define XFS_NRMAPADD_SPACE_RES(mp,b,w)\
> +	(((b + XFS_MAX_CONTIG_RMAPS_PER_BLOCK(mp) - 1) / \
> +	  XFS_MAX_CONTIG_RMAPS_PER_BLOCK(mp)) * \
> +	  XFS_RMAPADD_SPACE_RES(mp))

But then again the above is so much more readable than this, so maybe
it's a good idea after all and this one should be an inline as well.

Also I think future developers will really appreciate comments
explaining what we add up here.

Otherwise this looks fine and test fine for me:

Reviewed-by: Christoph Hellwig <hch@lst.de>
Tested-by: Christoph Hellwig <hch@lst.de>