This patch introduce some help routines used by next patch. It aims to
ease reviewing, while the next patch will concentrate on algorithm.
Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Cc: Grygorii Strashko <grygorii.strashko@xxxxxx>
Cc: Christoph Hellwig <hch@xxxxxxxxxxxxx>
Cc: Bjorn Helgaas <helgaas@xxxxxxxxxx>
Cc: Dave Young <dyoung@xxxxxxxxxx>
Cc: linux-pci@xxxxxxxxxxxxxxx
Cc: linuxppc-dev@xxxxxxxxxxxxxxxx
Signed-off-by: Pingfan Liu <kernelfans@xxxxxxxxx>
---
drivers/base/core.c | 38 ++++++++++++++++++++++++++++++++++++++
1 file changed, 38 insertions(+)
diff --git a/drivers/base/core.c b/drivers/base/core.c
index 36622b5..8113d2c 100644
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -123,6 +123,44 @@ static int device_is_dependent(struct device *dev, void *target)
return ret;
}
+struct pos_info {
+ struct device *pos;
+ struct device *tail;
+};
+
+/* caller takes the devices_kset->list_lock */
+static int descendants_reorder_after_pos(struct device *dev,
+ void *data)
+{
+ struct device *pos;
+ struct pos_info *p = data;
+
+ pos = p->pos;
+ pr_debug("devices_kset: Moving %s after %s\n",
+ dev_name(dev), dev_name(pos));
+ device_for_each_child(dev, p, descendants_reorder_after_pos);
+ /* children at the tail */
+ list_move(&dev->kobj.entry, &pos->kobj.entry);
+ /* record the right boundary of the section */
+ if (p->tail == NULL)
+ p->tail = dev;
+ return 0;
+}
+
+/* iterate over an open section */
+#define list_opensect_for_each_reverse(cur, left, right) \
+ for (cur = right->prev; cur == left; cur = cur->prev)
+
+static bool is_consumer(struct device *query, struct device *supplier)
+{
+ struct device_link *link;
+ /* todo, lock protection */
+ list_for_each_entry(link, &supplier->links.consumers, s_node)
+ if (link->consumer == query)
+ return true;
+ return false;
+}
+
static int device_reorder_to_tail(struct device *dev, void *not_used)
{
struct device_link *link;
--
2.7.4
