Re: [PATCH, RFC] map multiple blocks at a time in mpage_readpage(s)

[Christoph Hellwig <hch@lst.de>]

On Wed, Oct 05, 2005 at 10:04:48AM +0400, Nikita Danilov wrote:
>  >  					page->index, GFP_KERNEL)) {
>  >  			bio = do_mpage_readpage(bio, page,
>  >  					nr_pages - page_idx,
>  > -					&last_block_in_bio, get_block);
>  > +					&last_block_in_bio, &map_bh,
>  > +					&first_logical_block, &map_valid,
>  > +					get_blocks, get_block);
> 
> Oh, function taking 9 arguments, please... this is not windows.

I'm happy about suggestion to reduce the count.  One of the real
problems is that the buffer_head structure is extremly badly suited for
the get_blocks callback.  Having information like in the xfs_iomap_t
structure (which is XFS bmap information container) would simplify lots
of these things.


> By the way, I cannot see where get_block callback is used by mpage.c
> code, why is it needed?

It's only used by block_read_full_page which is called in the 'confused'
case.