48 	void (*calc_num_grefs)(struct xen_front_pgdir_shbuf *buf);
51 	void (*fill_page_dir)(struct xen_front_pgdir_shbuf *buf);
54 	int (*grant_refs_for_buffer)(struct xen_front_pgdir_shbuf *buf,
58 	int (*map)(struct xen_front_pgdir_shbuf *buf);
61 	int (*unmap)(struct xen_front_pgdir_shbuf *buf);
75 xen_front_pgdir_shbuf_get_dir_start(struct xen_front_pgdir_shbuf *buf)  in xen_front_pgdir_shbuf_get_dir_start()  argument
77 	if (!buf->grefs)  in xen_front_pgdir_shbuf_get_dir_start()
80 	return buf->grefs[0];  in xen_front_pgdir_shbuf_get_dir_start()
95 int xen_front_pgdir_shbuf_map(struct xen_front_pgdir_shbuf *buf)  in xen_front_pgdir_shbuf_map()  argument
97 	if (buf->ops && buf->ops->map)  in xen_front_pgdir_shbuf_map()
98 		return buf->ops->map(buf);  in xen_front_pgdir_shbuf_map()
116 int xen_front_pgdir_shbuf_unmap(struct xen_front_pgdir_shbuf *buf)  in xen_front_pgdir_shbuf_unmap()  argument
118 	if (buf->ops && buf->ops->unmap)  in xen_front_pgdir_shbuf_unmap()
119 		return buf->ops->unmap(buf);  in xen_front_pgdir_shbuf_unmap()
131 void xen_front_pgdir_shbuf_free(struct xen_front_pgdir_shbuf *buf)  in xen_front_pgdir_shbuf_free()  argument
133 	if (buf->grefs) {  in xen_front_pgdir_shbuf_free()
136 		for (i = 0; i < buf->num_grefs; i++)  in xen_front_pgdir_shbuf_free()
137 			if (buf->grefs[i] != INVALID_GRANT_REF)  in xen_front_pgdir_shbuf_free()
138 				gnttab_end_foreign_access(buf->grefs[i], NULL);  in xen_front_pgdir_shbuf_free()
140 	kfree(buf->grefs);  in xen_front_pgdir_shbuf_free()
141 	kfree(buf->directory);  in xen_front_pgdir_shbuf_free()
158 static int get_num_pages_dir(struct xen_front_pgdir_shbuf *buf)  in get_num_pages_dir()  argument
160 	return DIV_ROUND_UP(buf->num_pages, XEN_NUM_GREFS_PER_PAGE);  in get_num_pages_dir()
169 static void backend_calc_num_grefs(struct xen_front_pgdir_shbuf *buf)  in backend_calc_num_grefs()  argument
172 	buf->num_grefs = get_num_pages_dir(buf);  in backend_calc_num_grefs()
181 static void guest_calc_num_grefs(struct xen_front_pgdir_shbuf *buf)  in guest_calc_num_grefs()  argument
187 	buf->num_grefs = get_num_pages_dir(buf) + buf->num_pages;  in guest_calc_num_grefs()
200 static int backend_unmap(struct xen_front_pgdir_shbuf *buf)  in backend_unmap()  argument
205 	if (!buf->pages || !buf->backend_map_handles || !buf->grefs)  in backend_unmap()
208 	unmap_ops = kcalloc(buf->num_pages, sizeof(*unmap_ops),  in backend_unmap()
213 	for (i = 0; i < buf->num_pages; i++) {  in backend_unmap()
216 		addr = xen_page_to_vaddr(buf->pages[i]);  in backend_unmap()
218 				    buf->backend_map_handles[i]);  in backend_unmap()
221 	ret = gnttab_unmap_refs(unmap_ops, NULL, buf->pages,  in backend_unmap()
222 				buf->num_pages);  in backend_unmap()
224 	for (i = 0; i < buf->num_pages; i++) {  in backend_unmap()
226 			dev_err(&buf->xb_dev->dev,  in backend_unmap()
232 		dev_err(&buf->xb_dev->dev,  in backend_unmap()
236 	kfree(buf->backend_map_handles);  in backend_unmap()
237 	buf->backend_map_handles = NULL;  in backend_unmap()
247 static int backend_map(struct xen_front_pgdir_shbuf *buf)  in backend_map()  argument
253 	map_ops = kcalloc(buf->num_pages, sizeof(*map_ops), GFP_KERNEL);  in backend_map()
257 	buf->backend_map_handles = kcalloc(buf->num_pages,  in backend_map()
258 					   sizeof(*buf->backend_map_handles),  in backend_map()
260 	if (!buf->backend_map_handles) {  in backend_map()
270 	ptr = buf->directory;  in backend_map()
271 	grefs_left = buf->num_pages;  in backend_map()
273 	for (cur_dir_page = 0; cur_dir_page < buf->num_grefs; cur_dir_page++) {  in backend_map()
284 			addr = xen_page_to_vaddr(buf->pages[cur_page]);  in backend_map()
288 					  buf->xb_dev->otherend_id);  in backend_map()
295 	ret = gnttab_map_refs(map_ops, NULL, buf->pages, buf->num_pages);  in backend_map()
298 	for (cur_page = 0; cur_page < buf->num_pages; cur_page++) {  in backend_map()
300 			buf->backend_map_handles[cur_page] =  in backend_map()
303 			buf->backend_map_handles[cur_page] =  in backend_map()
307 			dev_err(&buf->xb_dev->dev,  in backend_map()
314 		dev_err(&buf->xb_dev->dev,  in backend_map()
316 		backend_unmap(buf);  in backend_map()
332 static void backend_fill_page_dir(struct xen_front_pgdir_shbuf *buf)  in backend_fill_page_dir()  argument
338 	ptr = buf->directory;  in backend_fill_page_dir()
339 	num_pages_dir = get_num_pages_dir(buf);  in backend_fill_page_dir()
345 		page_dir->gref_dir_next_page = buf->grefs[i + 1];  in backend_fill_page_dir()
359 static void guest_fill_page_dir(struct xen_front_pgdir_shbuf *buf)  in guest_fill_page_dir()  argument
364 	ptr = buf->directory;  in guest_fill_page_dir()
365 	num_pages_dir = get_num_pages_dir(buf);  in guest_fill_page_dir()
372 	grefs_left = buf->num_pages;  in guest_fill_page_dir()
382 			page_dir->gref_dir_next_page = buf->grefs[i + 1];  in guest_fill_page_dir()
384 		memcpy(&page_dir->gref, &buf->grefs[cur_gref],  in guest_fill_page_dir()
401 static int guest_grant_refs_for_buffer(struct xen_front_pgdir_shbuf *buf,  in guest_grant_refs_for_buffer()  argument
407 	otherend_id = buf->xb_dev->otherend_id;  in guest_grant_refs_for_buffer()
408 	for (i = 0; i < buf->num_pages; i++) {  in guest_grant_refs_for_buffer()
414 						xen_page_to_gfn(buf->pages[i]),  in guest_grant_refs_for_buffer()
416 		buf->grefs[gref_idx++] = cur_ref;  in guest_grant_refs_for_buffer()
430 static int grant_references(struct xen_front_pgdir_shbuf *buf)  in grant_references()  argument
436 	ret = gnttab_alloc_grant_references(buf->num_grefs, &priv_gref_head);  in grant_references()
438 		dev_err(&buf->xb_dev->dev,  in grant_references()
443 	otherend_id = buf->xb_dev->otherend_id;  in grant_references()
445 	num_pages_dir = get_num_pages_dir(buf);  in grant_references()
453 		frame = xen_page_to_gfn(virt_to_page(buf->directory +  in grant_references()
456 		buf->grefs[j++] = cur_ref;  in grant_references()
459 	if (buf->ops->grant_refs_for_buffer) {  in grant_references()
460 		ret = buf->ops->grant_refs_for_buffer(buf, &priv_gref_head, j);  in grant_references()
475 static int alloc_storage(struct xen_front_pgdir_shbuf *buf)  in alloc_storage()  argument
477 	buf->grefs = kcalloc(buf->num_grefs, sizeof(*buf->grefs), GFP_KERNEL);  in alloc_storage()
478 	if (!buf->grefs)  in alloc_storage()
481 	buf->directory = kcalloc(get_num_pages_dir(buf), PAGE_SIZE, GFP_KERNEL);  in alloc_storage()
482 	if (!buf->directory)  in alloc_storage()
517 	struct xen_front_pgdir_shbuf *buf = cfg->pgdir;  in xen_front_pgdir_shbuf_alloc()  local
521 		buf->ops = &backend_ops;  in xen_front_pgdir_shbuf_alloc()
523 		buf->ops = &local_ops;  in xen_front_pgdir_shbuf_alloc()
524 	buf->xb_dev = cfg->xb_dev;  in xen_front_pgdir_shbuf_alloc()
525 	buf->num_pages = cfg->num_pages;  in xen_front_pgdir_shbuf_alloc()
526 	buf->pages = cfg->pages;  in xen_front_pgdir_shbuf_alloc()
528 	buf->ops->calc_num_grefs(buf);  in xen_front_pgdir_shbuf_alloc()
530 	ret = alloc_storage(buf);  in xen_front_pgdir_shbuf_alloc()
534 	ret = grant_references(buf);  in xen_front_pgdir_shbuf_alloc()
538 	buf->ops->fill_page_dir(buf);  in xen_front_pgdir_shbuf_alloc()
543 	xen_front_pgdir_shbuf_free(buf);  in xen_front_pgdir_shbuf_alloc()