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* bio_vec, bv_page and folios
@ 2024-01-02  8:56 David Howells
  2024-01-02  9:15 ` Matthew Wilcox
  2024-01-02 10:03 ` David Howells
  0 siblings, 2 replies; 4+ messages in thread
From: David Howells @ 2024-01-02  8:56 UTC (permalink / raw)
  To: Christoph Hellwig, Matthew Wilcox
  Cc: dhowells, linux-fsdevel, linux-mm, linux-kernel

Hi Christoph, Willy,

Will bv_page in struct bio_vec ever become a folio pointer rather than I page
pointer?  I'm guessing not as it still presumably needs to be able to point to
non-folio pages.

David


^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: bio_vec, bv_page and folios
  2024-01-02  8:56 bio_vec, bv_page and folios David Howells
@ 2024-01-02  9:15 ` Matthew Wilcox
  2024-01-02 10:03 ` David Howells
  1 sibling, 0 replies; 4+ messages in thread
From: Matthew Wilcox @ 2024-01-02  9:15 UTC (permalink / raw)
  To: David Howells; +Cc: Christoph Hellwig, linux-fsdevel, linux-mm, linux-kernel

On Tue, Jan 02, 2024 at 08:56:46AM +0000, David Howells wrote:
> Hi Christoph, Willy,
> 
> Will bv_page in struct bio_vec ever become a folio pointer rather than I page
> pointer?  I'm guessing not as it still presumably needs to be able to point to
> non-folio pages.

My plan for bio_vec is that it becomes phyr -- a physical address +
length.  No more page or folio reference.

^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: bio_vec, bv_page and folios
  2024-01-02  8:56 bio_vec, bv_page and folios David Howells
  2024-01-02  9:15 ` Matthew Wilcox
@ 2024-01-02 10:03 ` David Howells
  2024-01-02 10:24   ` Matthew Wilcox
  1 sibling, 1 reply; 4+ messages in thread
From: David Howells @ 2024-01-02 10:03 UTC (permalink / raw)
  To: Matthew Wilcox
  Cc: dhowells, Christoph Hellwig, linux-fsdevel, linux-mm,
	linux-kernel

Matthew Wilcox <willy@infradead.org> wrote:

> On Tue, Jan 02, 2024 at 08:56:46AM +0000, David Howells wrote:
> > Hi Christoph, Willy,
> > 
> > Will bv_page in struct bio_vec ever become a folio pointer rather than I page
> > pointer?  I'm guessing not as it still presumably needs to be able to point to
> > non-folio pages.
> 
> My plan for bio_vec is that it becomes phyr -- a physical address +
> length.  No more page or folio reference.

Interesting...  What does that mean for those places that currently use
bv_page as a place to stash a pointer to the page and use it to clean up the
page later?

David


^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: bio_vec, bv_page and folios
  2024-01-02 10:03 ` David Howells
@ 2024-01-02 10:24   ` Matthew Wilcox
  0 siblings, 0 replies; 4+ messages in thread
From: Matthew Wilcox @ 2024-01-02 10:24 UTC (permalink / raw)
  To: David Howells; +Cc: Christoph Hellwig, linux-fsdevel, linux-mm, linux-kernel

On Tue, Jan 02, 2024 at 10:03:58AM +0000, David Howells wrote:
> Matthew Wilcox <willy@infradead.org> wrote:
> 
> > On Tue, Jan 02, 2024 at 08:56:46AM +0000, David Howells wrote:
> > > Hi Christoph, Willy,
> > > 
> > > Will bv_page in struct bio_vec ever become a folio pointer rather than I page
> > > pointer?  I'm guessing not as it still presumably needs to be able to point to
> > > non-folio pages.
> > 
> > My plan for bio_vec is that it becomes phyr -- a physical address +
> > length.  No more page or folio reference.
> 
> Interesting...  What does that mean for those places that currently use
> bv_page as a place to stash a pointer to the page and use it to clean up the
> page later?

I don't intend to get rid of bio_for_each_folio_all() or bio_add_page()
for example.  It's just a phys_to_page() away.  The advantage is that
we wouldn't need a struct page to do I/O to a physical address.

^ permalink raw reply	[flat|nested] 4+ messages in thread

end of thread, other threads:[~2024-01-02 10:24 UTC | newest]

Thread overview: 4+ messages (download: mbox.gz follow: Atom feed
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2024-01-02  8:56 bio_vec, bv_page and folios David Howells
2024-01-02  9:15 ` Matthew Wilcox
2024-01-02 10:03 ` David Howells
2024-01-02 10:24   ` Matthew Wilcox

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