Re: [PATCHv2 5/5] xfs: kill off l_sectbb_mask

[Christoph Hellwig <hch@xxxxxxxxxxxxx>]

On Fri, Apr 16, 2010 at 03:54:05PM -0500, Alex Elder wrote:
> + * Return the address of the start of the given block number's data
> + * in a log buffer.  The buffer covers a log sector-aligned region.
> + */
>  STATIC xfs_caddr_t
>  xlog_align(
>       xlog_t          *log,
> @@ -128,14 +132,14 @@ xlog_align(
>       int             nbblks,
>       xfs_buf_t       *bp)
>  {
> +     xfs_daddr_t     offset;
>       xfs_caddr_t     ptr;
>  
> -     if (log->l_sectBBsize == 1)
> -             return XFS_BUF_PTR(bp);
> +     offset = blk_no & ((xfs_daddr_t) log->l_sectBBsize - 1);
> +     ptr = XFS_BUF_PTR(bp) + BBTOB(offset);
> +
> +     ASSERT(ptr + BBTOB(nbblks) <= XFS_BUF_PTR(bp) + XFS_BUF_SIZE(bp));
>  
> -     ptr = XFS_BUF_PTR(bp) + BBTOB((int)blk_no & log->l_sectbb_mask);
> -     ASSERT(XFS_BUF_SIZE(bp) >=
> -             BBTOB(nbblks + (blk_no & log->l_sectbb_mask)));
>       return ptr;

And btw, now that I think about it we can just remove the
log->l_sectBBsize == 1 case entirely, so the whole thing could become:

STATIC xfs_caddr_t
xlog_align(
        struct log      *log,
        xfs_daddr_t     blk_no,
        int             nbblks,
        struct xfs_buf  *bp)
{
        xfs_daddr_t     offset;

        offset = blk_no & ((xfs_daddr_t) log->l_sectBBsize - 1);
        ASSERT(BBTOB(offset + nbblks) <= XFS_BUF_SIZE(bp));

        return XFS_BUF_PTR(bp) + BBTOB(offset);
}