diff options
Diffstat (limited to 'drivers/xen/gntdev.c')
-rw-r--r-- | drivers/xen/gntdev.c | 39 |
1 files changed, 34 insertions, 5 deletions
diff --git a/drivers/xen/gntdev.c b/drivers/xen/gntdev.c index 772a5b8..3987132 100644 --- a/drivers/xen/gntdev.c +++ b/drivers/xen/gntdev.c @@ -83,6 +83,7 @@ struct grant_map { struct ioctl_gntdev_grant_ref *grants; struct gnttab_map_grant_ref *map_ops; struct gnttab_unmap_grant_ref *unmap_ops; + struct gnttab_map_grant_ref *kmap_ops; struct page **pages; }; @@ -116,19 +117,22 @@ static struct grant_map *gntdev_alloc_map(struct gntdev_priv *priv, int count) add->grants = kzalloc(sizeof(add->grants[0]) * count, GFP_KERNEL); add->map_ops = kzalloc(sizeof(add->map_ops[0]) * count, GFP_KERNEL); add->unmap_ops = kzalloc(sizeof(add->unmap_ops[0]) * count, GFP_KERNEL); + add->kmap_ops = kzalloc(sizeof(add->kmap_ops[0]) * count, GFP_KERNEL); add->pages = kzalloc(sizeof(add->pages[0]) * count, GFP_KERNEL); if (NULL == add->grants || NULL == add->map_ops || NULL == add->unmap_ops || + NULL == add->kmap_ops || NULL == add->pages) goto err; - if (alloc_xenballooned_pages(count, add->pages)) + if (alloc_xenballooned_pages(count, add->pages, false /* lowmem */)) goto err; for (i = 0; i < count; i++) { add->map_ops[i].handle = -1; add->unmap_ops[i].handle = -1; + add->kmap_ops[i].handle = -1; } add->index = 0; @@ -142,6 +146,7 @@ err: kfree(add->grants); kfree(add->map_ops); kfree(add->unmap_ops); + kfree(add->kmap_ops); kfree(add); return NULL; } @@ -242,10 +247,35 @@ static int map_grant_pages(struct grant_map *map) gnttab_set_unmap_op(&map->unmap_ops[i], addr, map->flags, -1 /* handle */); } + } else { + /* + * Setup the map_ops corresponding to the pte entries pointing + * to the kernel linear addresses of the struct pages. + * These ptes are completely different from the user ptes dealt + * with find_grant_ptes. + */ + for (i = 0; i < map->count; i++) { + unsigned level; + unsigned long address = (unsigned long) + pfn_to_kaddr(page_to_pfn(map->pages[i])); + pte_t *ptep; + u64 pte_maddr = 0; + BUG_ON(PageHighMem(map->pages[i])); + + ptep = lookup_address(address, &level); + pte_maddr = arbitrary_virt_to_machine(ptep).maddr; + gnttab_set_map_op(&map->kmap_ops[i], pte_maddr, + map->flags | + GNTMAP_host_map | + GNTMAP_contains_pte, + map->grants[i].ref, + map->grants[i].domid); + } } pr_debug("map %d+%d\n", map->index, map->count); - err = gnttab_map_refs(map->map_ops, map->pages, map->count); + err = gnttab_map_refs(map->map_ops, use_ptemod ? map->kmap_ops : NULL, + map->pages, map->count); if (err) return err; @@ -461,13 +491,11 @@ static int gntdev_release(struct inode *inode, struct file *flip) pr_debug("priv %p\n", priv); - spin_lock(&priv->lock); while (!list_empty(&priv->maps)) { map = list_entry(priv->maps.next, struct grant_map, next); list_del(&map->next); gntdev_put_map(map); } - spin_unlock(&priv->lock); if (use_ptemod) mmu_notifier_unregister(&priv->mn, priv->mm); @@ -531,10 +559,11 @@ static long gntdev_ioctl_unmap_grant_ref(struct gntdev_priv *priv, map = gntdev_find_map_index(priv, op.index >> PAGE_SHIFT, op.count); if (map) { list_del(&map->next); - gntdev_put_map(map); err = 0; } spin_unlock(&priv->lock); + if (map) + gntdev_put_map(map); return err; } |