renegade-project/linux-next
2
0
Fork 0
mirror of https://github.com/edk2-porting/linux-next.git synced 2024-12-18 18:23:53 +08:00
Code
e24c745272
linux-next/include/linux/virtio_balloon.h

22 lines
657 B
C
Raw Normal View History

virtio: balloon driver After discussions with Anthony Liguori, it seems that the virtio balloon can be made even simpler. Here's my attempt. The device configuration tells the driver how much memory it should take from the guest (ie. balloon size). The guest feeds the page numbers it has taken via one virtqueue. A second virtqueue feeds the page numbers the driver wants back: if the device has the VIRTIO_BALLOON_F_MUST_TELL_HOST bit, then this queue is compulsory, otherwise it's advisory (and the guest can simply fault the pages back in). This driver can be enhanced later to deflate the balloon via a shrinker, oom callback or we could even go for a complete set of in-guest regulators. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-02-05 12:50:12 +08:00
#ifndef _LINUX_VIRTIO_BALLOON_H
#define _LINUX_VIRTIO_BALLOON_H
virtio: clarify that ABI is usable by any implementations We want others to implement and use virtio, so it makes sense to BSD license the non-__KERNEL__ parts of the headers to make this crystal clear. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Acked-by: Christian Borntraeger <borntraeger@de.ibm.com> Acked-by: Mark McLoughlin <markmc@redhat.com> Acked-by: Ryan Harper <ryanh@us.ibm.com> Acked-by: Eric Van Hensbergen <ericvh@gmail.com> Acked-by: Anthony Liguori <aliguori@us.ibm.com>
2008-07-26 01:06:03 +08:00
/* This header is BSD licensed so anyone can use the definitions to implement
* compatible drivers/servers. */
virtio: let header files include virtio_ids.h Rusty, commit 3ca4f5ca73057a617f9444a91022d7127041970a virtio: add virtio IDs file moved all device IDs into a single file. While the change itself is a very good one, it can break userspace applications. For example if a userspace tool wanted to get the ID of virtio_net it used to include virtio_net.h. This does no longer work, since virtio_net.h does not include virtio_ids.h. This patch moves all "#include <linux/virtio_ids.h>" from the C files into the header files, making the header files compatible with the old ones. In addition, this patch exports virtio_ids.h to userspace. CC: Fernando Luis Vazquez Cao <fernando@oss.ntt.co.jp> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-09-30 17:17:21 +08:00
#include <linux/virtio_ids.h>
virtio: balloon driver After discussions with Anthony Liguori, it seems that the virtio balloon can be made even simpler. Here's my attempt. The device configuration tells the driver how much memory it should take from the guest (ie. balloon size). The guest feeds the page numbers it has taken via one virtqueue. A second virtqueue feeds the page numbers the driver wants back: if the device has the VIRTIO_BALLOON_F_MUST_TELL_HOST bit, then this queue is compulsory, otherwise it's advisory (and the guest can simply fault the pages back in). This driver can be enhanced later to deflate the balloon via a shrinker, oom callback or we could even go for a complete set of in-guest regulators. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-02-05 12:50:12 +08:00
#include <linux/virtio_config.h>
/* The feature bitmap for virtio balloon */
#define VIRTIO_BALLOON_F_MUST_TELL_HOST 0 /* Tell before reclaiming pages */
virtio: avoid implicit use of Linux page size in balloon interface Make the balloon interface always use 4K pages, and convert Linux pfns if necessary. This patch assumes that Linux's PAGE_SHIFT will never be less than 12. Signed-off-by: Hollis Blanchard <hollisb@us.ibm.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (modified)
2008-11-14 05:48:33 +08:00
/* Size of a PFN in the balloon interface. */
#define VIRTIO_BALLOON_PFN_SHIFT 12
virtio: balloon driver After discussions with Anthony Liguori, it seems that the virtio balloon can be made even simpler. Here's my attempt. The device configuration tells the driver how much memory it should take from the guest (ie. balloon size). The guest feeds the page numbers it has taken via one virtqueue. A second virtqueue feeds the page numbers the driver wants back: if the device has the VIRTIO_BALLOON_F_MUST_TELL_HOST bit, then this queue is compulsory, otherwise it's advisory (and the guest can simply fault the pages back in). This driver can be enhanced later to deflate the balloon via a shrinker, oom callback or we could even go for a complete set of in-guest regulators. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-02-05 12:50:12 +08:00
struct virtio_balloon_config
{
/* Number of pages host wants Guest to give up. */
__le32 num_pages;
/* Number of pages we've actually got in balloon. */
__le32 actual;
};
#endif /* _LINUX_VIRTIO_BALLOON_H */
Copy Permalink