vfio: avoid inefficient operations on VFIO group in vfio_pin/unpin_pages
vfio_group_pin_pages() and vfio_group_unpin_pages() are introduced to
avoid inefficient search/check/ref/deref opertions associated with VFIO
group as those in each calling into vfio_pin_pages() and
vfio_unpin_pages().
VFIO group is taken as arg directly. The callers combine
search/check/ref/deref operations associated with VFIO group by calling
vfio_group_get_external_user()/vfio_group_get_external_user_from_dev()
beforehand, and vfio_group_put_external_user() afterwards.
Suggested-by: Alex Williamson <[email protected]>
Signed-off-by: Yan Zhao <[email protected]>
Signed-off-by: Alex Williamson <[email protected]>
diff --git a/include/linux/vfio.h b/include/linux/vfio.h
index 34b2fdf..be2bd35 100644
--- a/include/linux/vfio.h
+++ b/include/linux/vfio.h
@@ -111,6 +111,12 @@ extern int vfio_pin_pages(struct device *dev, unsigned long *user_pfn,
extern int vfio_unpin_pages(struct device *dev, unsigned long *user_pfn,
int npage);
+extern int vfio_group_pin_pages(struct vfio_group *group,
+ unsigned long *user_iova_pfn, int npage,
+ int prot, unsigned long *phys_pfn);
+extern int vfio_group_unpin_pages(struct vfio_group *group,
+ unsigned long *user_iova_pfn, int npage);
+
extern int vfio_dma_rw(struct vfio_group *group, dma_addr_t user_iova,
void *data, size_t len, bool write);
