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 <alex.williamson@redhat.com>
Signed-off-by: Yan Zhao <yan.y.zhao@intel.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
This commit is contained in:
Yan Zhao
2020-03-24 09:27:57 -06:00
committed by Alex Williamson
parent 8d46c0cca5
commit 40280cf7e8
2 changed files with 97 additions and 0 deletions

View File

@@ -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);