Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit a879211b authored by Daniel De Graaf's avatar Daniel De Graaf Committed by Konrad Rzeszutek Wilk
Browse files

xen-gntdev: Use find_vma rather than iterating our vma list manually 



This should be faster if many mappings exist, and also removes
the only user of map->vma not related to PTE modification.

Signed-off-by: default avatarDaniel De Graaf <dgdegra@tycho.nsa.gov>
Signed-off-by: default avatarKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
parent ef91082e

drivers/xen/gntdev.c

+8 −24
Original line number Diff line number Diff line
@@ -167,23 +167,6 @@ static struct grant_map *gntdev_find_map_index(struct gntdev_priv *priv, 
	return NULL;

}



static struct grant_map *gntdev_find_map_vaddr(struct gntdev_priv *priv,

					       unsigned long vaddr)

{

	struct grant_map *map;



	list_for_each_entry(map, &priv->maps, next) {

		if (!map->vma)

			continue;

		if (vaddr < map->vma->vm_start)

			continue;

		if (vaddr >= map->vma->vm_end)

			continue;

		return map;

	}

	return NULL;

}



static int gntdev_del_map(struct grant_map *map)

{

	int i;
@@ -494,22 +477,23 @@ static long gntdev_ioctl_get_offset_for_vaddr(struct gntdev_priv *priv, 
					      struct ioctl_gntdev_get_offset_for_vaddr __user *u)

{

	struct ioctl_gntdev_get_offset_for_vaddr op;

	struct vm_area_struct *vma;

	struct grant_map *map;



	if (copy_from_user(&op, u, sizeof(op)) != 0)

		return -EFAULT;

	pr_debug("priv %p, offset for vaddr %lx\n", priv, (unsigned long)op.vaddr);



	spin_lock(&priv->lock);

	map = gntdev_find_map_vaddr(priv, op.vaddr);

	if (map == NULL ||

	    map->vma->vm_start != op.vaddr) {

		spin_unlock(&priv->lock);

	vma = find_vma(current->mm, op.vaddr);

	if (!vma || vma->vm_ops != &gntdev_vmops)

		return -EINVAL;

	}



	map = vma->vm_private_data;

	if (!map)

		return -EINVAL;



	op.offset = map->index << PAGE_SHIFT;

	op.count = map->count;

	spin_unlock(&priv->lock);



	if (copy_to_user(u, &op, sizeof(op)) != 0)

		return -EFAULT;