Messages in this thread |  | | Date | Wed, 18 Oct 2000 01:00:48 +0200 | From | Andrea Arcangeli <> | Subject | Re: mapping user space buffer to kernel address space |
| |
On Tue, Oct 17, 2000 at 02:04:10PM -0700, Linus Torvalds wrote: > It so happens that the vmscan stuff won't ever remove a physical page > mapping, but that's simply because such a page CANNOT be swapped out. How
So if I write a mechanism that allows those driver-private-pages that are used for DMA of a soundcard to be swapped out, then you would remove the PG_referenced bitflag from them too?
What sense it has to start to writeout to disk a page that is under DMA when you don't know if this page is getting changed under the swapout? Furthmore despite of the swapout I/O those pages can't be freed until we run unmap_kiobuf.
> would you swap out the PCI space?
(minor note: that's not PCI space (the pci space case is handled by the !VALID_PAGE(page) check). That's normal kernel memory exported to userspace handled by the PageReserved(page) check.)
Andrea - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org Please read the FAQ at http://www.tux.org/lkml/
|  |