Re: [PATCH 2/2 V2] xfs: don't take addresses of packed xfs_rmap_key member

Christoph Hellwig
2020-01-29T18:29:37Z

On Wed, Jan 29, 2020 at 12:15:06PM -0600, Eric Sandeen wrote:
> {
> uint64_t off;
> + xfs_agblock_t start;
> int adj;
>
> adj = be32_to_cpu(rec->rmap.rm_blockcount) - 1;
>
> key->rmap.rm_startblock = rec->rmap.rm_startblock;
> - be32_add_cpu(&key->rmap.rm_startblock, adj);
> + start = be32_to_cpu(key->rmap.rm_startblock) - adj;
> + key->rmap.rm_startblock = cpu_to_be32(start);

Do we really need the local variable? Why not:

key->rmap.rm_startblock =
cpu_to_be32(be32_to_cpu(key->rmap.rm_startblock) - adj);