On 02/21/2018 03:03 AM, Oleksandr Andrushchenko wrote:This is a compile time check, so if kernel/Xen is configured
static int __init xen_drv_init(void)
{
+ /* At the moment we only support case with XEN_PAGE_SIZE == PAGE_SIZE */
+ BUILD_BUG_ON(XEN_PAGE_SIZE != PAGE_SIZE);
Why BUILD_BUG_ON? This should simply not load if page sizes are different.
I will rework BUG_* for map/unmap code to handle errors,
+ ret = gnttab_map_refs(map_ops, NULL, buf->pages, buf->num_pages);
+ BUG_ON(ret);
We should try not to BUG*(). There are a few in this patch (and possibly
others) that I think can be avoided.
this is called in xen_drm_front_shbuf_alloc and is properly cleaned
+You need to clean up on errors.
+static int alloc_storage(struct xen_drm_front_shbuf *buf)
+{
+ if (buf->sgt) {
+ buf->pages = kvmalloc_array(buf->num_pages,
+ sizeof(struct page *), GFP_KERNEL);
+ if (!buf->pages)
+ return -ENOMEM;
+
+ if (drm_prime_sg_to_page_addr_arrays(buf->sgt, buf->pages,
+ NULL, buf->num_pages) < 0)
+ return -EINVAL;
+ }
+
+ buf->grefs = kcalloc(buf->num_grefs, sizeof(*buf->grefs), GFP_KERNEL);
+ if (!buf->grefs)
+ return -ENOMEM;
+
+ buf->directory = kcalloc(get_num_pages_dir(buf), PAGE_SIZE, GFP_KERNEL);
+ if (!buf->directory)
+ return -ENOMEM;
-boris
+
+ return 0;
+}