[PATCH 3/9] xfs: add discontiguous buffer map interface

[Christoph Hellwig]

> +	struct xfs_buf_map	map = {
> +		.bm_bn = blkno,
> +		.bm_len = numblks,
> +	};

I'm not a big fan of creative macro use, but with the amount of copies
of these line why not add a:

#define DEFINE_SINGLE_BUF_MAP(map, blkno, numblk) \
struct xfs_buf_map (map) = { .bm_bn = (blkno), .bm_len = (numblk) };

Otherwise looks good,

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