On Friday 06 September 2002 00:19, Andrew Morton wrote:
> I'm not sure what semantics we really want for this. If we were to
> "invalidate" a mapped page then it would become anonymous, which
> makes some sense.
There's no need to leave the page mapped, you can easily walk the rmap list
and remove the references.
> If the VM wants to reclaim a page, and it has PG_private set then
> the vm will run mapping->releasepage() against the page. The mapping's
> releasepage must try to clear away whatever is held at ->private. If
> that was successful then releasepage() must clear PG_private, decrement
> page->count and return non-zero. If the info at ->private is not
> freeable, releasepage returns zero. ->releasepage() may not sleep in
> 2.5.
>
> So. NFS can put anything it likes at page->private. If you're not
> doing that then you don't need a releasepage. If you are doing that
> then you must have a releasepage().
Right now, there are no filesystems actually doing anything filesystem
specific here, are there? I really wonder if making this field, formerly
known as buffers, opaque to the vfs is the right idea.
-- Daniel - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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