2  * Client-facing interface for the Xenbus driver.  In other words, the
3  * interface between the Xenbus and the device-specific code, be it the
115  * xenbus_watch_path - register a watch
123  * success, or -errno on error.  On success, the given @path will be saved as
124  * @watch->node, and remains the caller's to free.  On error, @watch->node will
137 	watch->node = path;  in xenbus_watch_path()
138 	watch->will_handle = will_handle;  in xenbus_watch_path()
139 	watch->callback = callback;  in xenbus_watch_path()
144 		watch->node = NULL;  in xenbus_watch_path()
145 		watch->will_handle = NULL;  in xenbus_watch_path()
146 		watch->callback = NULL;  in xenbus_watch_path()
156  * xenbus_watch_pathfmt - register a watch on a sprintf-formatted path
164  * Return 0 on success, or -errno on error.  On success, the watched path
165  * (@path/@path2) will be saved as @watch->node, and becomes the caller's to
166  * kfree().  On error, watch->node will be NULL, so the caller has nothing to
187 		xenbus_dev_fatal(dev, -ENOMEM, "allocating path for watch");  in xenbus_watch_pathfmt()
188 		return -ENOMEM;  in xenbus_watch_pathfmt()
214 	   (something it was trying to in the past) because dev->state  in __xenbus_switch_state()
222 	if (state == dev->state)  in __xenbus_switch_state()
234 	err = xenbus_scanf(xbt, dev->nodename, "state", "%d", &current_state);  in __xenbus_switch_state()
238 	err = xenbus_printf(xbt, dev->nodename, "state", "%d", state);  in __xenbus_switch_state()
248 		if (err == -EAGAIN && !abort)  in __xenbus_switch_state()
252 		dev->state = state;  in __xenbus_switch_state()
263  * Return 0 on success, or -errno on error.  On error, the device will switch
276 	complete(&dev->down);  in xenbus_frontend_closed()
294 	len = sprintf(printf_buffer, "%i ", -err);  in xenbus_va_dev_error()
295 	vsnprintf(printf_buffer + len, PRINTF_BUFFER_SIZE - len, fmt, ap);  in xenbus_va_dev_error()
297 	dev_err(&dev->dev, "%s\n", printf_buffer);  in xenbus_va_dev_error()
299 	path_buffer = kasprintf(GFP_KERNEL, "error/%s", dev->nodename);  in xenbus_va_dev_error()
375  * -errno on error.  On error, the device will switch to
392 		err = gnttab_grant_foreign_access(dev->otherend_id, gfn, 0);  in xenbus_grant_ring()
415  * created local port to *port.  Return 0 on success, or -errno on error.  On
425 	alloc_unbound.remote_dom = dev->otherend_id;  in xenbus_alloc_evtchn()
440  * Free an existing event channel. Returns 0 on success or -errno on error.
468  * sets *vaddr to that address.  Returns 0 on success, and -errno on
481 		return -EINVAL;  in xenbus_map_ring_valloc()
485 		return -ENOMEM;  in xenbus_map_ring_valloc()
487 	info->node = kzalloc(sizeof(*info->node), GFP_KERNEL);  in xenbus_map_ring_valloc()
488 	if (!info->node)  in xenbus_map_ring_valloc()
489 		err = -ENOMEM;  in xenbus_map_ring_valloc()
491 		err = ring_ops->map(dev, info, gnt_refs, nr_grefs, vaddr);  in xenbus_map_ring_valloc()
493 	kfree(info->node);  in xenbus_map_ring_valloc()
499 /* N.B. sizeof(phys_addr_t) doesn't always equal to sizeof(unsigned
500  * long), e.g. 32-on-64.  Caller is responsible for preparing the
513 		return -EINVAL;  in __xenbus_map_ring()
516 		gnttab_set_map_op(&info->map[i], info->phys_addrs[i], flags,  in __xenbus_map_ring()
517 				  gnt_refs[i], dev->otherend_id);  in __xenbus_map_ring()
521 	gnttab_batch_map(info->map, i);  in __xenbus_map_ring()
524 		if (info->map[i].status != GNTST_okay) {  in __xenbus_map_ring()
525 			xenbus_dev_fatal(dev, info->map[i].status,  in __xenbus_map_ring()
527 					 gnt_refs[i], dev->otherend_id);  in __xenbus_map_ring()
530 			handles[i] = info->map[i].handle;  in __xenbus_map_ring()
538 			gnttab_set_unmap_op(&info->unmap[j],  in __xenbus_map_ring()
539 					    info->phys_addrs[i],  in __xenbus_map_ring()
545 	BUG_ON(HYPERVISOR_grant_table_op(GNTTABOP_unmap_grant_ref, info->unmap, j));  in __xenbus_map_ring()
549 		if (info->unmap[i].status != GNTST_okay) {  in __xenbus_map_ring()
555 	return -ENOENT;  in __xenbus_map_ring()
577 		return -EINVAL;  in xenbus_unmap_ring()
607 	info->phys_addrs[info->idx] = vaddr;  in xenbus_map_ring_setup_grant_hvm()
608 	info->addrs[info->idx] = vaddr;  in xenbus_map_ring_setup_grant_hvm()
610 	info->idx++;  in xenbus_map_ring_setup_grant_hvm()
619 	struct xenbus_map_node *node = info->node;  in xenbus_map_ring_hvm()
625 	err = xen_alloc_unpopulated_pages(nr_pages, node->hvm.pages);  in xenbus_map_ring_hvm()
629 	gnttab_foreach_grant(node->hvm.pages, nr_grefs,  in xenbus_map_ring_hvm()
633 	err = __xenbus_map_ring(dev, gnt_ref, nr_grefs, node->handles,  in xenbus_map_ring_hvm()
635 	node->nr_handles = nr_grefs;  in xenbus_map_ring_hvm()
640 	addr = vmap(node->hvm.pages, nr_pages, VM_MAP | VM_IOREMAP,  in xenbus_map_ring_hvm()
643 		err = -ENOMEM;  in xenbus_map_ring_hvm()
647 	node->hvm.addr = addr;  in xenbus_map_ring_hvm()
650 	list_add(&node->next, &xenbus_valloc_pages);  in xenbus_map_ring_hvm()
654 	info->node = NULL;  in xenbus_map_ring_hvm()
660 		xenbus_unmap_ring(dev, node->handles, nr_grefs, info->addrs);  in xenbus_map_ring_hvm()
666 		xen_free_unpopulated_pages(nr_pages, node->hvm.pages);  in xenbus_map_ring_hvm()
685 	return ring_ops->unmap(dev, vaddr);  in xenbus_unmap_ring_vfree()
694 	info->phys_addrs[info->idx++] = arbitrary_virt_to_machine(pte).maddr;  in map_ring_apply()
704 	struct xenbus_map_node *node = info->node;  in xenbus_map_ring_pv()
707 	int err = -ENOMEM;  in xenbus_map_ring_pv()
711 		return -ENOMEM;  in xenbus_map_ring_pv()
712 	if (apply_to_page_range(&init_mm, (unsigned long)area->addr,  in xenbus_map_ring_pv()
715 	err = __xenbus_map_ring(dev, gnt_refs, nr_grefs, node->handles,  in xenbus_map_ring_pv()
721 	node->nr_handles = nr_grefs;  in xenbus_map_ring_pv()
722 	node->pv.area = area;  in xenbus_map_ring_pv()
725 	list_add(&node->next, &xenbus_valloc_pages);  in xenbus_map_ring_pv()
728 	*vaddr = area->addr;  in xenbus_map_ring_pv()
729 	info->node = NULL;  in xenbus_map_ring_pv()
753 		if (node->pv.area->addr == vaddr) {  in xenbus_unmap_ring_pv()
754 			list_del(&node->next);  in xenbus_unmap_ring_pv()
763 		xenbus_dev_error(dev, -ENOENT,  in xenbus_unmap_ring_pv()
768 	for (i = 0; i < node->nr_handles; i++) {  in xenbus_unmap_ring_pv()
776 		unmap[i].handle = node->handles[i];  in xenbus_unmap_ring_pv()
783 	for (i = 0; i < node->nr_handles; i++) {  in xenbus_unmap_ring_pv()
788 					 node->handles[i], unmap[i].status);  in xenbus_unmap_ring_pv()
795 		free_vm_area(node->pv.area);  in xenbus_unmap_ring_pv()
798 			 node->pv.area, node->nr_handles);  in xenbus_unmap_ring_pv()
823 	info->addrs[info->idx] = (unsigned long)gfn_to_virt(gfn);  in xenbus_unmap_ring_setup_grant_hvm()
825 	info->idx++;  in xenbus_unmap_ring_setup_grant_hvm()
840 		addr = node->hvm.addr;  in xenbus_unmap_ring_hvm()
842 			list_del(&node->next);  in xenbus_unmap_ring_hvm()
851 		xenbus_dev_error(dev, -ENOENT,  in xenbus_unmap_ring_hvm()
856 	nr_pages = XENBUS_PAGES(node->nr_handles);  in xenbus_unmap_ring_hvm()
858 	gnttab_foreach_grant(node->hvm.pages, node->nr_handles,  in xenbus_unmap_ring_hvm()
862 	rv = xenbus_unmap_ring(dev, node->handles, node->nr_handles,  in xenbus_unmap_ring_hvm()
866 		xen_free_unpopulated_pages(nr_pages, node->hvm.pages);  in xenbus_unmap_ring_hvm()