Re: [patch 1/3] fs: add an iovec iterator

["Nate Diller" <nate.diller@gmail.com>]

On 2/8/07, Nick Piggin <npiggin@suse.de> wrote:
> On Thu, Feb 08, 2007 at 07:49:53PM +0000, Christoph Hellwig wrote:
> > On Thu, Feb 08, 2007 at 02:07:24PM +0100, Nick Piggin wrote:
> > > Add an iterator data structure to operate over an iovec. Add usercopy
> > > operators needed by generic_file_buffered_write, and convert that function
> > > over.
> >
> > iovec_iterator is an awfully long and not very descriptive name.
> > In past discussions we named this thingy iodesc and wanted to pass it
> > down all the I/O path, including the file operations.
>
> Hi Christoph,
>
> Sure I think it would be a good idea to shorten the name. And yes, although
> I just construct the iterator to pass into perform_write, I think it should
> make sense to go much further up the call stack instead of passing all those
> args around. iodesc seems like a fine name, so I'll use that unless
> anyone objects.

i had a patch integrating the iodesc idea, but after some thought, had
decided to call it struct file_io.  That name reflects the fact that
it's doing I/O in arbitrary lengths with byte offsets, and struct
file_io *fio contrasts well with struct bio (block_io).  I also had
used the field ->nbytes instead of ->count, to clarify the difference
between segment iterators, segment offsets, and absolute bytecount.

FYI, the patch is still in the works and would convert the whole file
I/O stack to use the new structure.  I would like to base it off of
this work as well if this makes it into -mm (as I think it should)

NATE